- Email: [email protected]
Preclinical evaluation targeting both IGF1R and IR in triple negative breast cancer
abstracts
Annals of Oncology
Legal entity responsible for the study: Menarini Ricerche S.p.A. Funding: Menarini Ricerche S.p.A. Disclosure: A. Fiascarelli: Full / Part-time employment: Menarini RIcerche S.p.A. G. Merlino: Full / Part-time employment: Menarini Ricerche S.p.A. S. Capano: Full / Part-time employment: Menarini Ricerche S.p.A. A. Paoli: Full / Part-time employment: Menarini Ricerche S.p.A.. A. Bressan: Full / Part-time employment: Menarini Ricerche. M. Bigioni: Full / Part-time employment: Menarini Ricerche S.p.A.. M. Scaltriti: Advisory / Consultancy: Memorial Sloan-Kettering Cancer Center. J. Arribas: Advisory / Consultancy: Vall d’Hebron Institute of Oncology. C. Bernad o Morales: Advisory / Consultancy: Vall d’Hebron Institute of Oncology. A. Pellacani: Leadership role, Full / Part-time employment: Menarini Ricerche S.p.A.. M. Salerno: Leadership role, Full / Part-time employment: Menarini Ricerche. M. Binaschi: Leadership role, Full / Part-time employment: Menarini Ricerche S.p.A.
Neat-1: Culprit lnRNA tying PIG-C, MSLN, CD80 in TNBC
authors have declared no conflicts of interest. 1
1
2
N.H. Hussein , H.M. El Tayebi , M. de Bruyn Genetic Pharmacology Research Group, Department of Pharmacology and Toxicology, German University in Cairo, Cairo, Egypt, 2Obstrectics and Gynecology, University Hospital Groningen (UMCG), Groningen, Netherlands
1
Background: Continuous effort unraveled GPI pathway that anchors cell surface proteins mediating tumor microenvironment interactions. GPI axis is initiated in breast cancer upon PIG-C elevation which induces MSLN surface expession. MSLN is antiapoptotic GPI-AP, whose immune therapies yielded tremendous results. CD80 is a unique immunomodulator that binds to CD28, CTLA4 and PDL1. Recombinant GPICD80 is evaluated as tumor vaccine. RNAi is a promising tool for immuno-targeted therapy as crucial immuno modulators are blocked. Our aim is to investigate impact of nc-RNAs on MSLN, PIG-C and CD80 for the first time. Methods: miR-2355, miR-455 and NEAT-1 targeted MSLN, PIG-C and CD80 by bioinformatic analysis. MSLN/CD80 plasmids were transfected in MDA-MB-231 cells, then treated with synthetic nc-RNAs. Surface CD80 and MSLN were assessed by flow cytometry.Gene mRNA level was tested by q-PCR. Results: PIG-C Silencing, NEAT-1 and miR-2355 elevation, plus NEAT-1/miR-2355 combination droped PIG-C mRNA level signtificantly (p < 0.0001 each) compared to untreated cells and miR-2355 inhibitor (P < 0.0001) miR-2355 elevation significantly droped MSLN mRNA level compared to untreated cells (P < 0.0001) Conversely, miR2355 inhibitor, NEAT-1 mimic and NEAT-1/miR-2355 combination significantly increased MSLN expression level (P < 0.0001 each). PIG-C siRNA did not have significant effect on MSLN mRNA level PIG-C siRNA and miR-2355 mimic significantly droped MSLN surface level MFI compared to mock (P < 0.0001 each) but miR-2355 inhibitor significantly increased MSLN MFI (P < 0.0001) NEAT-1 mimic and NEAT1/miR-2355 combination did not have significant effect on MSLN MFI. miR-455 mimic signifincantly droped both surface CD80 MFI and CD80 mRNA level compared to mock (P < 0.0001) Contrastingly, miR-455 inhibitor significantly increased both CD80 MFI and CD80 mRNA level compare to mock (P < 0.0001) NEAT-1 mimic and NEAT-1/miR-455 combination did not show significant effect on CD80 MFI or CD80 mRNA level. Conclusions: To sum up, our study sheds light on new targets for breast cancer immunotherapy. NEAT-1 is dominant promising sponge for several mi-RNAs which potientiates its role in governing many immunomoduolatory pathways. Our study paves the way for future investigations on the role of NEAT-1 in immuno-targeted therapy. Legal entity responsible for the study: The authors. Funding: Has not received any funding. Disclosure: All authors have declared no conflicts of interest.
1940P
A novel RAF/MEK inhibitor CH5126766 in phase I clinical trial has an effectiveness in the combination with eribulin for the treatment of triple negative breast cancer
1941P
E.M. Galan-Moya1, M. Nuncia-Cantarero1, L. Serrano-Oviedo1, S. Morcillo-Garcıa1, orffy3, A. Oca~ na4 C. Nieto-Jime´nez2, M. Burgos2, B. Gy} 1 Medical Sciences & Regional Center for Biomedical Research, University of Castilla-La Mancha, Albacete, Spain, 2Oncologıa Traslacional, Complejo Hospitalario Universitario de Albacete, Albacete, Spain, 3Institute of Enzymology, MTA TTK Lendu¨let Cancer Biomarker Research Group, Budapest, Hungary, 4Drugs Development, Hospital Clınico San Carlos, Madrid, Spain Background: Triple negative breast cancers (TNBC) are enriched with cells bearing stem-like features (CSC), which underlie cancer progression, thus targeting stemness could be an interesting treatment approach. In turn, the epigenetic machinery is crucial for the maintenance of the stemness phenotype. The BET family of epigenetic readers are emerging as novel targets for cancer therapy and have shown preclinical effect in breast cancer. In this work we evaluate the effect of the BET inhibitor (BETi) JQ1 on stemness in TNBC. Methods: Transcriptomic, functional annotation and qPCR studies were performed on JQ1-exposed TNBC cells. Results were confirmed on spheroids and spheroid-derived tumours. Limiting dilution assays, matrigel invasion experiments, immunofluorescence staining, and flow cytometry studies were also performed to evaluate the effect of JQ1 on CSC features. For the outcome analysis, the online tool Kaplan-Meier Plotter and an integrated response database were used. Results: JQ1 can modify the expression of stemness-related genes incultured TNBC cells. Among these changes, the CD44/CD24 and ALDH1A1 expression, both classical stemness markers, were diminished by JQ1. Using a validated spheroid model, to mimic the intrinsic characteristics of CSCs, we show that JQ1 decreased surface expression of CD44, inhibited self-renewal and invasion, and induced cells arrest in G0/G1, therefore altering the stemness phenotype in TNBC. Four of the identified stemness genes, GJA1, CD24, EPCAM, and SOX9, were found to be associated with worse patient outcome in TNBC. Furthermore, ABCG2 and RUNX2 predicted low response to chemotherapy in TNBC patients. Conclusions: In this work we show how BETi modify the stemness landscape in TNBC. Thus, we propose a novel role for JQ1 as a stemness-targeting drug. Loss of the stem cell phenotype via JQ1 treatment could lead to less aggressive and more chemo-sensitive tumours, which would reflect in better patient prognosis. Legal entity responsible for the study: The authors. Funding: Has not received any funding. Disclosure: All authors have declared no conflicts of interest.
1942P H. Ono, M. Horinaka, S. Yasuda, M. Morita, E. Nishimoto, T. Sakai Drug Discovery Medicine, Kyoto Prefectural University of Medicine, Kyoto, Japan Background: Eribulin is one of the well-tolerated microtubule dynamics inhibitor made in Japan, and it has been reported to be especially effective for triple negative breast cancer (TNBC) with poor prognosis. We previously reported the possibility of the combination treatment of eribulin and a novel HDAC inhibitor OBP-801 for the promising strategy against TNBC patients. We also interestingly showed that the combination more potently suppressed a MAPK pathway than each agent. Therefore, in this study we investigated the effect of new combination therapy, eribulin and a RAF/ MEK inhibitor in TNBC. Methods: We used CH5126766 as a novel RAF/MEK inhibitor. The phase I clinical trial of CH5126766 is now in progress in the U.S. We investigated the combination effect of eribulin and CH5126766 using some TNBC cell lines. The cell growth was analyzed through WST-8 assay and colony formation assay, and the flow cytometry analysis was conducted to evaluate the induction of apoptosis. The mechanism underlying the enhancement of inhibition of TNBC growth was investigated through Western blot analyses. We also analyzed the combination effect through the onco-immunological mechanism.
v782 | Translational Research
Identification of a stemness-related gene panel associated with BET inhibition in triple negative breast cancer
Preclinical evaluation targeting both IGF1R and IR in triple negative breast cancer
A.J. Eustace1, S. Roche1, N. Mukherjee1, F. O’Neill1, N. Conlon1, J. Meiller1, D.M. Collins1, P. Gaule1, A. Canonici1, S.F. Madden2, N. O’Donovan1, J. Crown3 1 National Institute for Cellular Biotechnology, Dublin City University, Dublin, Ireland, 2 Data Science Centre, Royal College of Surgeons, Dublin, Ireland, 3Medical Oncology, St Vincents University Hospital, Dublin, Ireland Background: Insulin Receptor (INSR) signalling may play a role in resistance to insulin-like growth factor receptor (IGF1R) therapy. Although IGF1R is frequently expressed in triple negative breast cancer (TNBC), we found that an IGF1R monoclonal antibody did not inhibit the growth of TNBC cells. Thus, we hypothesised that dual targeting of IGF1R and INSR may be more effective in TNBC. Methods: Relative mRNA expression of INSR and IGFIR were analysed across different subtypes of breast cancer using the BreastMark database. INSR-A, INSR-B, IGF1R and insulin like growth factor 2 (IGFII) was quantified by qRT-PCR in a panel of 11 TNBC cell lines. Proliferation assays were performed on TNBC cell lines treated with the dual IR/INSR inhibitor Linsitinib (OSI-906). Combinations were performed by testing
Volume 30 | Supplement 5 | October 2019
Downloaded from https://academic.oup.com/annonc/article-abstract/30/Supplement_5/mdz268.069/5576885 by guest on 26 October 2019
1939P
Results: The combination treatment showed the inhibition of the TNBC cell growth in both short and long incubation. The mechanism of this combination is due to the enhancement of apoptosis. The apoptosis in the combination was induced with the suppression of anti-apoptotic protein survivin in the TNBC cells. Though eribulin upregulated survivin, CH5126766 could potently suppress the survivin expression induced by eribulin. On the other hand, eribulin could suppress the Akt pathway induced as the result of the resistance of the MAPK pathway. Moreover, CH5126766 might be effective in this combination through the onco-immunological mechanism. Conclusions: We found that the combination of eribulin and CH5126766 inhibits the growth with apoptosis in TNBC, raising the possibility that the combination might be a novel promising strategy for patients suffering from TNBC with the upregulation of MAPK pathway. Legal entity responsible for the study: The authors. Funding: Has not received any funding. Disclosure: T. Sakai: Research grant / Funding (institution), Licensing / Royalties: Chugai. All other
abstracts
Annals of Oncology
Crown: Honoraria (self), Speaker Bureau / Expert testimony, Research grant / Funding (institution): Boehringer Ingleheim; Shareholder / Stockholder / Stock options, Full / Part-time employment: OncoMark Limited; Honoraria (self), Advisory / Consultancy, Speaker Bureau / Expert testimony, Research grant / Funding (institution): Eisai; Honoraria (self): Amgen; Honoraria (self), Advisory / Consultancy, Research grant / Funding (institution): Puma Biotechnology; Honoraria (self), Advisory / Consultancy: Seattle Genetics; Honoraria (self), Advisory / Consultancy, Speaker Bureau / Expert testimony, Travel / Accommodation / Expenses: Pfizer; Honoraria (self), Advisory / Consultancy: Vertex; Honoraria (self), Speaker Bureau / Expert testimony: Genomic Health; Honoraria (self), Advisory / Consultancy, Research grant / Funding (institution), Travel / Accommodation / Expenses: Roche; Honoraria (self), Travel / Accommodation / Expenses: MSD Oncology; Travel / Accommodation / Expenses: AstraZeneca; Travel / Accommodation / Expenses: Abbvie. All other authors have declared no conflicts of interest.
1943P
Monospecific antibody targeting of CDH11 inhibits epithelial-tomesenchymal transition and represses cancer stem cell-like phenotype by up-regulating miR-335 in metastatic breast cancer, in vitro and in vivo
J-H. Chen Medical Department, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan Background: Metastasis is a leading cause of breast cancer mortality. The induction of epithelial-to-mesenchymal transition (EMT) and complex oncogenic signaling is a vital step in the evolution of highly metastatic and therapeutically-intractable breast cancer; necessitating novel target discovery or development of therapeutics that target metastatic breast cells (MBCs). Methods: To achieve this, this study employs a combination of in silico bioinformatics analyses, protein and transcript analyses, drug sensitivity assays, functional assays and animal studies. Results: CDH11 as an inductor and/or facilitator of metastatic signaling, and biomarker of poor prognosis in MBCs. Furthermore, we showed that in the presence of CDH11-rich cancer-associated fibroblasts (CAFs), MCF7 and MDA-MB-231 MBC cell lines acquired enhanced metastatic phenotype with increased CDH11, b-catenin, vimentin, and fibronectin (FN) expression. exposure to anti-CDH11 antibody suppresses metastasis, reduces CDH11, FN and b-catenin expression, and abrogate the cancer stem cell (CSC)-like traits of MBC cells. Interestingly, ectopic expression of miR-335 suppressed CDH11, b-catenin and vimentin expression, in concert with attenuated metastatic and CSC potentials of the MBC cells; conversely, inhibition of miR335 resulted in increased metastatic potential. Finally, corroborating the in silica and in vitro findings, in vivo assays showed that the administration of anti-CDH11 antibody or miR-335 mimic suppressed tumorigenesis and inhibited cancer metastasis. Conclusions: These findings indicate that miR-335 mediates anti-CDH11 antibody therapy response and that an enhanced miR-335/CDH11 ratio elicits marked suppression of the MBC CSC-like and metastatic phenotypes, thus revealing a therapeuticallyexploitable inverse correlation between CDH11-enhanced CSC-like and metastatic phenotype and miR-335 expression in MBCs. Thus, we highlight the therapeutic promise of humanized anti-CDH11 antibodies or miR-335-mimic, making a case for their clinical application as efficacious therapeutic option in patients with MBC. Legal entity responsible for the study: The author. Funding: Has not received any funding. Disclosure: The author has declared no conflicts of interest.
1944P
Pharmacological screening with Chk1 inhibitors identifies synergistic agents to overcome resistance to platinums in basal breast and ovarian cancer
A.L.A. Sanabria1, C. Nieto-Jime´nez1, V. Corrales-Sanchez1, J.C. Montero2, M. Burgos1, na4 E.M. Galan-Moya3, A. Pandiella2, A. Oca~ 1 Oncologıa Traslacional, Complejo Hospitalario Universitario de Albacete, Albacete, on del C ancer, Salamanca, Spain, Spain, 2Laboratorio 15, Centro de Investigaci 3 Oncologıa Traslacional, Universidad de Castilla-La Mancha, Albacete, Spain, 4Drugs Development, Hospital Clınico San Carlos, Madrid, Spain Background: Metastatic ovarian and basal-like breast cancers are incurable diseases with limited therapeutic options. In our study, we explored synergistic interactions of Chk1 inhibitors (rabusertib and SAR020106) with approved therapies in these indications. In addition, we evaluated the role of these agents to overcome platinum resistance. Methods: We evaluate the effect of rabusertib and chemotherapic agents in ovarian (OVCAR3, OVCAR8, IGROV1, SKOV3) and breast (MDA-MB-231, HS578T, BT549, HCC3153) cancer cell lines. We also use the commercially available cell line A2780Rcis and a breast cancer model created in our laboratory, MDA-MB231Rcis. Results: The combination of platinum agents, cisplatin and carboplatin was synergistic with Chk1 inhibitors rabusertib and SAR020106 in most of basal-like and ovarian cancer cell lines. The combination of rabusertib with gemcitabine was very synergistic in basal-like cell lines but not in ovarian cancer. Doxorubicin, another DNA damaging agent, was also synergistic in ovarian cell lines, but showed less activity in the breast models. Combinations with topotecan were slightly synergistic only in basal-like tumors. The combination of rabusertib with agents that target mitosis were not synergistic. The combination of Chk1 inhibitor with platinum compounds or gemcitabine affects colony formation and tumor invasiveness. Combination of platinum agents and gemcitabine with rabusertib induced cell death that was mainly mediated by caspases. The effect of rabusertib on platinum resistance showed addition of Chk1 inhibitor to cisplatin induces cell death in cisplatin resistant cells. Conclusions: Inhibition of Chk1 has a strong synergistic interaction with DNA damaging agents, including platinum compounds, gemcitabine and olaparib, on both tumor types. The effect of rabusertib with platinum agents and gemcitabine on colony growth and long-term effect confirms the effect on proliferation, invasion and long-term survival in basal-like and ovarian cancer cell lines. Addition of rabusertib to cisplatin induces cell death in all the cell lines including the resistant cells, demonstrate that resistance to cisplatin can be overcome by inhibition of Chk1 kinase. Legal entity responsible for the study: Alberto Oca~ na. Funding: Instituto de Salud Carlos III (PI16/01121) Diputaci on de Albacete and CIBERONC CRIS Cancer Foundation cancer association ACEPAIN research program of the UCLM regional fellowship for Biomedicine and Health science research (II2018_11). Disclosure: All authors have declared no conflicts of interest.
1945P
Comparison of 11 circulating miRNAs and CA125 kinetics in ovarian cancer during first line treatment: Data from the randomized CHIVA trial (a GINECO-GCIG study)
P. Robelin1, M. Tod2, O. Colomban1, I.L. Ray-Coquard3, G. De Rauglaudre4, J. Florence5, A. Chevalier6, P. combe7, A. Lortholary8, S. Hamizi9, N. Raban10, G. Ferron11, J. Meunier12, D. Berton-Rigaud13, J. Alexandre14, M-C. Kaminsky-Forrett15, C. Dubot16, A. Leary17, E. Malaurie18, B. You19 1 EMR3738, Ciblage The´rapeutique en Oncologie, Faculte´ de Me´decine et de Maı¨eutique Lyon-Sud Charles Me´rieux, , Oullins, France, 2Pharmacie, Hoˆpital de la Croix Rousse, Hospices Civils de Lyon, Lyon, France, 3Medical Oncology, Centre Le´on Be´rard, Lyon, France, 4Oncologie Radiothe´rapie, Institut Sainte-Catherine, Avignon, France, 5 Calvados, Centre Francois Balesse, Caen, France, 6Cancerologie Gynecologie, Centre Oscar Lambret, Lille, France, 7Oncologie Medicale, Hopital European George Pompidou, Paris, France, 8Oncologie Me´dicale, Hoˆpital Prive´ du Confluent S.A.S., Nantes France, 9 Oncologie Medicale, Centre Hospitalier Lyon Sud, Pierre Be´nite, France, 10Poˆle Re´gional de Cance´rologie, Service d’Oncologie, Hoˆpital de la Mile´trie - CHU de Poitiers, Poitiers, France, 11De´partement de Chirurgie Oncologique, Institut Claudius Regaud, Toulouse, France, 12Service d’Oncologie Me´dicale, Centre Hospitalier Re´gional d’Orle´ans, Orleans, France, 13Oncologie Me´dicale, ICO Institut de Cancerologie de l’Ouest Rene´ Gauducheau, Saint-Herblain, France, 14Unite´ d’Oncologie Me´dicale, Hoˆpital Cochin, Paris, France, 15Oncologie Me´dicale, ICL Institut de Cance´rologie de Lorraine, Vandoeuvre-les-Nancy, France, 16Oncologie Me´dicale, Hoˆpital Rene´ Huguenin - Institut Curie, St. Cloud, France, 17Gynecologic Unit, Gustave Roussy Cancer Center, INSERM U981, and Groupe d’Investigateurs Nationaux pour l’Etude des Cancers Ovariens (GINECO), Villejuif, France, 18Oncologie, Radiothe´rapie, CHI de Cre´teil, Cre´teil, France, 19 Oncology, Centre Hospitalier Lyon Sud, Pierre Be´nite, France Background: MicroRNAs (miRNAs) are promising biomarkers in ovarian cancer. Their kinetics during treatment might be useful for monitoring disease burden, and guiding treatments in patients treated with neoadjuvant chemotherapy and interval debulking surgery (IDS). Methods: Serial blood samples of patients enrolled in the randomized phase II CHIVA trial, comparing neo-adjuvant carboplatin-paclitaxel þ/- nintedanib (NCT01583322),
Volume 30 | Supplement 5 | October 2019
doi:10.1093/annonc/mdz268 | v783
Downloaded from https://academic.oup.com/annonc/article-abstract/30/Supplement_5/mdz268.069/5576885 by guest on 26 October 2019
Linsitinib with Xentuzumab (BI-836845), cisplatin, docetaxel, or the PI3K inhibitor Dactolisib (NVP-BEZ235). We also tested the anti-proliferative effect of Linsitinib in combination with Xentuzumab when stimulated with IGF-I and IGF-II following serum-starvation for 24 hours. Finally, Linsitinib was tested in HCC-1143 xenografts to assess the effect of low-dose treatment on tumour formation. Results: No significant differences were observed between the basal-like and non-basallike cell lines for IR or IGF1R mRNA expression. However, IGF-II mRNA was more frequently detected in non-basal-like (80%, 4/5) compared to basal-like cell lines (20%, 1/ 5). Only three of the 12 cell lines tested showed sensitivity to Linsitinib with IC50 values less than 10 mM. The two most sensitive cell lines, HDQ-P1 and HCC1143, expressed detectable levels of IGF1R, INSR-A and INSR-B mRNAs. Although Linsitinib blocked IGF-I and IGF-II stimulated proliferation in both HCC1143 and HDQ-P1 cells, addition of Linsitinib to either chemotherapy or Dactolisib did not enhance therapeutic response. Linisitinib did not reduce tumour formation or tumour growth in an in vivo TNBC cell-line xenograft model. Conclusions: Although IGF1R has been shown to be frequently expressed in TNBC, our in vitro and in vivo data suggest that it may not be a good therapeutic target in the TNBC subtype. Legal entity responsible for the study: The authors. Funding: Boehringer Ingleheim. Disclosure: N. O’Donovan: Research grant / Funding (institution): Boehringer Ingleheim. J.
Annals of Oncology
Legal entity responsible for the study: Menarini Ricerche S.p.A. Funding: Menarini Ricerche S.p.A. Disclosure: A. Fiascarelli: Full / Part-time employment: Menarini RIcerche S.p.A. G. Merlino: Full / Part-time employment: Menarini Ricerche S.p.A. S. Capano: Full / Part-time employment: Menarini Ricerche S.p.A. A. Paoli: Full / Part-time employment: Menarini Ricerche S.p.A.. A. Bressan: Full / Part-time employment: Menarini Ricerche. M. Bigioni: Full / Part-time employment: Menarini Ricerche S.p.A.. M. Scaltriti: Advisory / Consultancy: Memorial Sloan-Kettering Cancer Center. J. Arribas: Advisory / Consultancy: Vall d’Hebron Institute of Oncology. C. Bernad o Morales: Advisory / Consultancy: Vall d’Hebron Institute of Oncology. A. Pellacani: Leadership role, Full / Part-time employment: Menarini Ricerche S.p.A.. M. Salerno: Leadership role, Full / Part-time employment: Menarini Ricerche. M. Binaschi: Leadership role, Full / Part-time employment: Menarini Ricerche S.p.A.
Neat-1: Culprit lnRNA tying PIG-C, MSLN, CD80 in TNBC
authors have declared no conflicts of interest. 1
1
2
N.H. Hussein , H.M. El Tayebi , M. de Bruyn Genetic Pharmacology Research Group, Department of Pharmacology and Toxicology, German University in Cairo, Cairo, Egypt, 2Obstrectics and Gynecology, University Hospital Groningen (UMCG), Groningen, Netherlands
1
Background: Continuous effort unraveled GPI pathway that anchors cell surface proteins mediating tumor microenvironment interactions. GPI axis is initiated in breast cancer upon PIG-C elevation which induces MSLN surface expession. MSLN is antiapoptotic GPI-AP, whose immune therapies yielded tremendous results. CD80 is a unique immunomodulator that binds to CD28, CTLA4 and PDL1. Recombinant GPICD80 is evaluated as tumor vaccine. RNAi is a promising tool for immuno-targeted therapy as crucial immuno modulators are blocked. Our aim is to investigate impact of nc-RNAs on MSLN, PIG-C and CD80 for the first time. Methods: miR-2355, miR-455 and NEAT-1 targeted MSLN, PIG-C and CD80 by bioinformatic analysis. MSLN/CD80 plasmids were transfected in MDA-MB-231 cells, then treated with synthetic nc-RNAs. Surface CD80 and MSLN were assessed by flow cytometry.Gene mRNA level was tested by q-PCR. Results: PIG-C Silencing, NEAT-1 and miR-2355 elevation, plus NEAT-1/miR-2355 combination droped PIG-C mRNA level signtificantly (p < 0.0001 each) compared to untreated cells and miR-2355 inhibitor (P < 0.0001) miR-2355 elevation significantly droped MSLN mRNA level compared to untreated cells (P < 0.0001) Conversely, miR2355 inhibitor, NEAT-1 mimic and NEAT-1/miR-2355 combination significantly increased MSLN expression level (P < 0.0001 each). PIG-C siRNA did not have significant effect on MSLN mRNA level PIG-C siRNA and miR-2355 mimic significantly droped MSLN surface level MFI compared to mock (P < 0.0001 each) but miR-2355 inhibitor significantly increased MSLN MFI (P < 0.0001) NEAT-1 mimic and NEAT1/miR-2355 combination did not have significant effect on MSLN MFI. miR-455 mimic signifincantly droped both surface CD80 MFI and CD80 mRNA level compared to mock (P < 0.0001) Contrastingly, miR-455 inhibitor significantly increased both CD80 MFI and CD80 mRNA level compare to mock (P < 0.0001) NEAT-1 mimic and NEAT-1/miR-455 combination did not show significant effect on CD80 MFI or CD80 mRNA level. Conclusions: To sum up, our study sheds light on new targets for breast cancer immunotherapy. NEAT-1 is dominant promising sponge for several mi-RNAs which potientiates its role in governing many immunomoduolatory pathways. Our study paves the way for future investigations on the role of NEAT-1 in immuno-targeted therapy. Legal entity responsible for the study: The authors. Funding: Has not received any funding. Disclosure: All authors have declared no conflicts of interest.
1940P
A novel RAF/MEK inhibitor CH5126766 in phase I clinical trial has an effectiveness in the combination with eribulin for the treatment of triple negative breast cancer
1941P
E.M. Galan-Moya1, M. Nuncia-Cantarero1, L. Serrano-Oviedo1, S. Morcillo-Garcıa1, orffy3, A. Oca~ na4 C. Nieto-Jime´nez2, M. Burgos2, B. Gy} 1 Medical Sciences & Regional Center for Biomedical Research, University of Castilla-La Mancha, Albacete, Spain, 2Oncologıa Traslacional, Complejo Hospitalario Universitario de Albacete, Albacete, Spain, 3Institute of Enzymology, MTA TTK Lendu¨let Cancer Biomarker Research Group, Budapest, Hungary, 4Drugs Development, Hospital Clınico San Carlos, Madrid, Spain Background: Triple negative breast cancers (TNBC) are enriched with cells bearing stem-like features (CSC), which underlie cancer progression, thus targeting stemness could be an interesting treatment approach. In turn, the epigenetic machinery is crucial for the maintenance of the stemness phenotype. The BET family of epigenetic readers are emerging as novel targets for cancer therapy and have shown preclinical effect in breast cancer. In this work we evaluate the effect of the BET inhibitor (BETi) JQ1 on stemness in TNBC. Methods: Transcriptomic, functional annotation and qPCR studies were performed on JQ1-exposed TNBC cells. Results were confirmed on spheroids and spheroid-derived tumours. Limiting dilution assays, matrigel invasion experiments, immunofluorescence staining, and flow cytometry studies were also performed to evaluate the effect of JQ1 on CSC features. For the outcome analysis, the online tool Kaplan-Meier Plotter and an integrated response database were used. Results: JQ1 can modify the expression of stemness-related genes incultured TNBC cells. Among these changes, the CD44/CD24 and ALDH1A1 expression, both classical stemness markers, were diminished by JQ1. Using a validated spheroid model, to mimic the intrinsic characteristics of CSCs, we show that JQ1 decreased surface expression of CD44, inhibited self-renewal and invasion, and induced cells arrest in G0/G1, therefore altering the stemness phenotype in TNBC. Four of the identified stemness genes, GJA1, CD24, EPCAM, and SOX9, were found to be associated with worse patient outcome in TNBC. Furthermore, ABCG2 and RUNX2 predicted low response to chemotherapy in TNBC patients. Conclusions: In this work we show how BETi modify the stemness landscape in TNBC. Thus, we propose a novel role for JQ1 as a stemness-targeting drug. Loss of the stem cell phenotype via JQ1 treatment could lead to less aggressive and more chemo-sensitive tumours, which would reflect in better patient prognosis. Legal entity responsible for the study: The authors. Funding: Has not received any funding. Disclosure: All authors have declared no conflicts of interest.
1942P H. Ono, M. Horinaka, S. Yasuda, M. Morita, E. Nishimoto, T. Sakai Drug Discovery Medicine, Kyoto Prefectural University of Medicine, Kyoto, Japan Background: Eribulin is one of the well-tolerated microtubule dynamics inhibitor made in Japan, and it has been reported to be especially effective for triple negative breast cancer (TNBC) with poor prognosis. We previously reported the possibility of the combination treatment of eribulin and a novel HDAC inhibitor OBP-801 for the promising strategy against TNBC patients. We also interestingly showed that the combination more potently suppressed a MAPK pathway than each agent. Therefore, in this study we investigated the effect of new combination therapy, eribulin and a RAF/ MEK inhibitor in TNBC. Methods: We used CH5126766 as a novel RAF/MEK inhibitor. The phase I clinical trial of CH5126766 is now in progress in the U.S. We investigated the combination effect of eribulin and CH5126766 using some TNBC cell lines. The cell growth was analyzed through WST-8 assay and colony formation assay, and the flow cytometry analysis was conducted to evaluate the induction of apoptosis. The mechanism underlying the enhancement of inhibition of TNBC growth was investigated through Western blot analyses. We also analyzed the combination effect through the onco-immunological mechanism.
v782 | Translational Research
Identification of a stemness-related gene panel associated with BET inhibition in triple negative breast cancer
Preclinical evaluation targeting both IGF1R and IR in triple negative breast cancer
A.J. Eustace1, S. Roche1, N. Mukherjee1, F. O’Neill1, N. Conlon1, J. Meiller1, D.M. Collins1, P. Gaule1, A. Canonici1, S.F. Madden2, N. O’Donovan1, J. Crown3 1 National Institute for Cellular Biotechnology, Dublin City University, Dublin, Ireland, 2 Data Science Centre, Royal College of Surgeons, Dublin, Ireland, 3Medical Oncology, St Vincents University Hospital, Dublin, Ireland Background: Insulin Receptor (INSR) signalling may play a role in resistance to insulin-like growth factor receptor (IGF1R) therapy. Although IGF1R is frequently expressed in triple negative breast cancer (TNBC), we found that an IGF1R monoclonal antibody did not inhibit the growth of TNBC cells. Thus, we hypothesised that dual targeting of IGF1R and INSR may be more effective in TNBC. Methods: Relative mRNA expression of INSR and IGFIR were analysed across different subtypes of breast cancer using the BreastMark database. INSR-A, INSR-B, IGF1R and insulin like growth factor 2 (IGFII) was quantified by qRT-PCR in a panel of 11 TNBC cell lines. Proliferation assays were performed on TNBC cell lines treated with the dual IR/INSR inhibitor Linsitinib (OSI-906). Combinations were performed by testing
Volume 30 | Supplement 5 | October 2019
Downloaded from https://academic.oup.com/annonc/article-abstract/30/Supplement_5/mdz268.069/5576885 by guest on 26 October 2019
1939P
Results: The combination treatment showed the inhibition of the TNBC cell growth in both short and long incubation. The mechanism of this combination is due to the enhancement of apoptosis. The apoptosis in the combination was induced with the suppression of anti-apoptotic protein survivin in the TNBC cells. Though eribulin upregulated survivin, CH5126766 could potently suppress the survivin expression induced by eribulin. On the other hand, eribulin could suppress the Akt pathway induced as the result of the resistance of the MAPK pathway. Moreover, CH5126766 might be effective in this combination through the onco-immunological mechanism. Conclusions: We found that the combination of eribulin and CH5126766 inhibits the growth with apoptosis in TNBC, raising the possibility that the combination might be a novel promising strategy for patients suffering from TNBC with the upregulation of MAPK pathway. Legal entity responsible for the study: The authors. Funding: Has not received any funding. Disclosure: T. Sakai: Research grant / Funding (institution), Licensing / Royalties: Chugai. All other
abstracts
Annals of Oncology
Crown: Honoraria (self), Speaker Bureau / Expert testimony, Research grant / Funding (institution): Boehringer Ingleheim; Shareholder / Stockholder / Stock options, Full / Part-time employment: OncoMark Limited; Honoraria (self), Advisory / Consultancy, Speaker Bureau / Expert testimony, Research grant / Funding (institution): Eisai; Honoraria (self): Amgen; Honoraria (self), Advisory / Consultancy, Research grant / Funding (institution): Puma Biotechnology; Honoraria (self), Advisory / Consultancy: Seattle Genetics; Honoraria (self), Advisory / Consultancy, Speaker Bureau / Expert testimony, Travel / Accommodation / Expenses: Pfizer; Honoraria (self), Advisory / Consultancy: Vertex; Honoraria (self), Speaker Bureau / Expert testimony: Genomic Health; Honoraria (self), Advisory / Consultancy, Research grant / Funding (institution), Travel / Accommodation / Expenses: Roche; Honoraria (self), Travel / Accommodation / Expenses: MSD Oncology; Travel / Accommodation / Expenses: AstraZeneca; Travel / Accommodation / Expenses: Abbvie. All other authors have declared no conflicts of interest.
1943P
Monospecific antibody targeting of CDH11 inhibits epithelial-tomesenchymal transition and represses cancer stem cell-like phenotype by up-regulating miR-335 in metastatic breast cancer, in vitro and in vivo
J-H. Chen Medical Department, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan Background: Metastasis is a leading cause of breast cancer mortality. The induction of epithelial-to-mesenchymal transition (EMT) and complex oncogenic signaling is a vital step in the evolution of highly metastatic and therapeutically-intractable breast cancer; necessitating novel target discovery or development of therapeutics that target metastatic breast cells (MBCs). Methods: To achieve this, this study employs a combination of in silico bioinformatics analyses, protein and transcript analyses, drug sensitivity assays, functional assays and animal studies. Results: CDH11 as an inductor and/or facilitator of metastatic signaling, and biomarker of poor prognosis in MBCs. Furthermore, we showed that in the presence of CDH11-rich cancer-associated fibroblasts (CAFs), MCF7 and MDA-MB-231 MBC cell lines acquired enhanced metastatic phenotype with increased CDH11, b-catenin, vimentin, and fibronectin (FN) expression. exposure to anti-CDH11 antibody suppresses metastasis, reduces CDH11, FN and b-catenin expression, and abrogate the cancer stem cell (CSC)-like traits of MBC cells. Interestingly, ectopic expression of miR-335 suppressed CDH11, b-catenin and vimentin expression, in concert with attenuated metastatic and CSC potentials of the MBC cells; conversely, inhibition of miR335 resulted in increased metastatic potential. Finally, corroborating the in silica and in vitro findings, in vivo assays showed that the administration of anti-CDH11 antibody or miR-335 mimic suppressed tumorigenesis and inhibited cancer metastasis. Conclusions: These findings indicate that miR-335 mediates anti-CDH11 antibody therapy response and that an enhanced miR-335/CDH11 ratio elicits marked suppression of the MBC CSC-like and metastatic phenotypes, thus revealing a therapeuticallyexploitable inverse correlation between CDH11-enhanced CSC-like and metastatic phenotype and miR-335 expression in MBCs. Thus, we highlight the therapeutic promise of humanized anti-CDH11 antibodies or miR-335-mimic, making a case for their clinical application as efficacious therapeutic option in patients with MBC. Legal entity responsible for the study: The author. Funding: Has not received any funding. Disclosure: The author has declared no conflicts of interest.
1944P
Pharmacological screening with Chk1 inhibitors identifies synergistic agents to overcome resistance to platinums in basal breast and ovarian cancer
A.L.A. Sanabria1, C. Nieto-Jime´nez1, V. Corrales-Sanchez1, J.C. Montero2, M. Burgos1, na4 E.M. Galan-Moya3, A. Pandiella2, A. Oca~ 1 Oncologıa Traslacional, Complejo Hospitalario Universitario de Albacete, Albacete, on del C ancer, Salamanca, Spain, Spain, 2Laboratorio 15, Centro de Investigaci 3 Oncologıa Traslacional, Universidad de Castilla-La Mancha, Albacete, Spain, 4Drugs Development, Hospital Clınico San Carlos, Madrid, Spain Background: Metastatic ovarian and basal-like breast cancers are incurable diseases with limited therapeutic options. In our study, we explored synergistic interactions of Chk1 inhibitors (rabusertib and SAR020106) with approved therapies in these indications. In addition, we evaluated the role of these agents to overcome platinum resistance. Methods: We evaluate the effect of rabusertib and chemotherapic agents in ovarian (OVCAR3, OVCAR8, IGROV1, SKOV3) and breast (MDA-MB-231, HS578T, BT549, HCC3153) cancer cell lines. We also use the commercially available cell line A2780Rcis and a breast cancer model created in our laboratory, MDA-MB231Rcis. Results: The combination of platinum agents, cisplatin and carboplatin was synergistic with Chk1 inhibitors rabusertib and SAR020106 in most of basal-like and ovarian cancer cell lines. The combination of rabusertib with gemcitabine was very synergistic in basal-like cell lines but not in ovarian cancer. Doxorubicin, another DNA damaging agent, was also synergistic in ovarian cell lines, but showed less activity in the breast models. Combinations with topotecan were slightly synergistic only in basal-like tumors. The combination of rabusertib with agents that target mitosis were not synergistic. The combination of Chk1 inhibitor with platinum compounds or gemcitabine affects colony formation and tumor invasiveness. Combination of platinum agents and gemcitabine with rabusertib induced cell death that was mainly mediated by caspases. The effect of rabusertib on platinum resistance showed addition of Chk1 inhibitor to cisplatin induces cell death in cisplatin resistant cells. Conclusions: Inhibition of Chk1 has a strong synergistic interaction with DNA damaging agents, including platinum compounds, gemcitabine and olaparib, on both tumor types. The effect of rabusertib with platinum agents and gemcitabine on colony growth and long-term effect confirms the effect on proliferation, invasion and long-term survival in basal-like and ovarian cancer cell lines. Addition of rabusertib to cisplatin induces cell death in all the cell lines including the resistant cells, demonstrate that resistance to cisplatin can be overcome by inhibition of Chk1 kinase. Legal entity responsible for the study: Alberto Oca~ na. Funding: Instituto de Salud Carlos III (PI16/01121) Diputaci on de Albacete and CIBERONC CRIS Cancer Foundation cancer association ACEPAIN research program of the UCLM regional fellowship for Biomedicine and Health science research (II2018_11). Disclosure: All authors have declared no conflicts of interest.
1945P
Comparison of 11 circulating miRNAs and CA125 kinetics in ovarian cancer during first line treatment: Data from the randomized CHIVA trial (a GINECO-GCIG study)
P. Robelin1, M. Tod2, O. Colomban1, I.L. Ray-Coquard3, G. De Rauglaudre4, J. Florence5, A. Chevalier6, P. combe7, A. Lortholary8, S. Hamizi9, N. Raban10, G. Ferron11, J. Meunier12, D. Berton-Rigaud13, J. Alexandre14, M-C. Kaminsky-Forrett15, C. Dubot16, A. Leary17, E. Malaurie18, B. You19 1 EMR3738, Ciblage The´rapeutique en Oncologie, Faculte´ de Me´decine et de Maı¨eutique Lyon-Sud Charles Me´rieux, , Oullins, France, 2Pharmacie, Hoˆpital de la Croix Rousse, Hospices Civils de Lyon, Lyon, France, 3Medical Oncology, Centre Le´on Be´rard, Lyon, France, 4Oncologie Radiothe´rapie, Institut Sainte-Catherine, Avignon, France, 5 Calvados, Centre Francois Balesse, Caen, France, 6Cancerologie Gynecologie, Centre Oscar Lambret, Lille, France, 7Oncologie Medicale, Hopital European George Pompidou, Paris, France, 8Oncologie Me´dicale, Hoˆpital Prive´ du Confluent S.A.S., Nantes France, 9 Oncologie Medicale, Centre Hospitalier Lyon Sud, Pierre Be´nite, France, 10Poˆle Re´gional de Cance´rologie, Service d’Oncologie, Hoˆpital de la Mile´trie - CHU de Poitiers, Poitiers, France, 11De´partement de Chirurgie Oncologique, Institut Claudius Regaud, Toulouse, France, 12Service d’Oncologie Me´dicale, Centre Hospitalier Re´gional d’Orle´ans, Orleans, France, 13Oncologie Me´dicale, ICO Institut de Cancerologie de l’Ouest Rene´ Gauducheau, Saint-Herblain, France, 14Unite´ d’Oncologie Me´dicale, Hoˆpital Cochin, Paris, France, 15Oncologie Me´dicale, ICL Institut de Cance´rologie de Lorraine, Vandoeuvre-les-Nancy, France, 16Oncologie Me´dicale, Hoˆpital Rene´ Huguenin - Institut Curie, St. Cloud, France, 17Gynecologic Unit, Gustave Roussy Cancer Center, INSERM U981, and Groupe d’Investigateurs Nationaux pour l’Etude des Cancers Ovariens (GINECO), Villejuif, France, 18Oncologie, Radiothe´rapie, CHI de Cre´teil, Cre´teil, France, 19 Oncology, Centre Hospitalier Lyon Sud, Pierre Be´nite, France Background: MicroRNAs (miRNAs) are promising biomarkers in ovarian cancer. Their kinetics during treatment might be useful for monitoring disease burden, and guiding treatments in patients treated with neoadjuvant chemotherapy and interval debulking surgery (IDS). Methods: Serial blood samples of patients enrolled in the randomized phase II CHIVA trial, comparing neo-adjuvant carboplatin-paclitaxel þ/- nintedanib (NCT01583322),
Volume 30 | Supplement 5 | October 2019
doi:10.1093/annonc/mdz268 | v783
Downloaded from https://academic.oup.com/annonc/article-abstract/30/Supplement_5/mdz268.069/5576885 by guest on 26 October 2019
Linsitinib with Xentuzumab (BI-836845), cisplatin, docetaxel, or the PI3K inhibitor Dactolisib (NVP-BEZ235). We also tested the anti-proliferative effect of Linsitinib in combination with Xentuzumab when stimulated with IGF-I and IGF-II following serum-starvation for 24 hours. Finally, Linsitinib was tested in HCC-1143 xenografts to assess the effect of low-dose treatment on tumour formation. Results: No significant differences were observed between the basal-like and non-basallike cell lines for IR or IGF1R mRNA expression. However, IGF-II mRNA was more frequently detected in non-basal-like (80%, 4/5) compared to basal-like cell lines (20%, 1/ 5). Only three of the 12 cell lines tested showed sensitivity to Linsitinib with IC50 values less than 10 mM. The two most sensitive cell lines, HDQ-P1 and HCC1143, expressed detectable levels of IGF1R, INSR-A and INSR-B mRNAs. Although Linsitinib blocked IGF-I and IGF-II stimulated proliferation in both HCC1143 and HDQ-P1 cells, addition of Linsitinib to either chemotherapy or Dactolisib did not enhance therapeutic response. Linisitinib did not reduce tumour formation or tumour growth in an in vivo TNBC cell-line xenograft model. Conclusions: Although IGF1R has been shown to be frequently expressed in TNBC, our in vitro and in vivo data suggest that it may not be a good therapeutic target in the TNBC subtype. Legal entity responsible for the study: The authors. Funding: Boehringer Ingleheim. Disclosure: N. O’Donovan: Research grant / Funding (institution): Boehringer Ingleheim. J.