- Email: [email protected]
Plasma Malondialdehyde and Ischemia-modified Albumin levels in breast cancer patients before and after adjuvant chemotherapy
S44
Poster Abstracts I / The Breast 32S1 (2017) S22–S77
P061 Plasma Malondialdehyde and Ischemia-modified Albumin levels in breast cancer patients before and after adjuvant chemotherapy T.O. Topcu1 *, H. Kavgaci2, F. Ozdemir2, A. Mentese3, A. Orem3, F. Aydin2 . 1Division of Medical Oncology, Medeniyet University Goztepe Training and Research Hospital, Istanbul, Turkey, 2Division of Medical Oncology, School of Medicine, Karadeniz Technical University, Trabzon, Turkey, 3 Department of Biochemistry, School of Medicine, Karadeniz Technical University, Trabzon, Turkey Aims: Breast cancer is the most common cancer among women. Oxidative stress plays an important role in carcinogenesis. Oxidative stress affects cell metabolism, signaling pathways, gene expression, cell proliferation and apoptosis. The aim of this study was to investigate plasma levels of malondialdehyde (MDA) and ischemiamodified albumin (IMA), novel oxidative stress biomarkers, and to assess the effect of anthracycline-based chemotherapy on plasma MDA and IMA in patients with operable breast cancer. Methods: Fifty-five patients with operable breast cancer and 35 agematched healthy controls were enrolled. Levels of MDA and IMA were investigated before and after adjuvant chemotherapy. Basal levels ( pre-chemotherapy) of MDA and IMA in patients were compared with those in healthy controls and with patient levels after 3 cycles of chemotherapy. Levels of MDA and IMA were determined using the ELISA method. Results: MDA levels were significantly higher in patients than in the controls ( p < 0.001) are shown in Table 1. IMA levels were also higher in patients, but the difference was not significant ( p: 0.12). Postchemotherapy MDA levels were lower than basal levels ( p < 0.001). No difference was determined between basal and post-chemotherapy IMA levels. We determined a significant correlation between prechemotherapy CA 15-3 and MPV and post-chemotherapy MDA levels ( p < 0.001 r: 0.512 and p: 0.006, r: 0.382, respectively). Table 2 MDA, İMA levels in pre-chemotherapy and control groups Variable
Prechemotherapy
MDA IMA
0.28±0.10 0.53±0.90
Controls
P
0.14±0.66 0.50±0.90
<0.001 0.12
Conclusions: The oxidative-antioxidant balance is impaired in breast cancer patients. In conclusion, we observed elevated MDA levels in our breast cancer patients. This may indicate an oxidative imbalance involving increased oxidative agents and decreased anti-oxidant defense. Our study shows that this imbalance causes progression of operable breast cancer. Further chemotherapy and close monitoring should be considered in cases of breast cancer with increased MDA levels after adjuvant chemotherapy. Elevated MDA levels after adjuvant chemotherapy may indicate drug resistance. High plasma MDA levels before and after adjuvant chemotherapy appear to be a poor prognostic factor for breast cancer patients independent of tumor pathology type. This study represents the first investigation of IMA levels in these patients. Increased MDA levels are more accurate than plasma IMA levels in showing oxidative imbalance in operated breast cancer patients. Disclosure of Interest: No significant relationships. P062 RANK-c isoform inhibits stimuli-dependent NF-kappaB signaling and aggressiveness of ER-negative breast cancer cells C. Sirinian, A. Papanastasiou, H. Kalofonos*. Molecular and Clinical Oncology Laboratory, Division of Oncology, Department of Medicine, University of Patras, Patras, Greece Aims: We have previously shown that RANK-c is an isoform of RANK receptor (TNFRSF11A) produced through alternative splicing,
affecting RANK-dependent NF-kappaB activation. In this study we aimed to elucidate differences of RANK-c expression and function between estrogen receptor (ER) positive and ER-negative breast cancer cells. Methods: A panel of human breast cancer cell lines (MCF7, T47D, SKBR3, BT474, MDA-MB-231) was employed for RANK-c mRNA expression and functional analyses. Expression analysis was done by real time PCR on RNA from breast cancer cell lines and transcript specific primers. Through transient transfection and luciferase assays we evaluated RANK-c contribution on NF-kB activation. Stable cell lines were generated for isoform functional characterization through MTT assay, wound healing, transwell and matrigel assays. Results: Estrogen receptor-positive cell lines (MCF7 and T47D) presented with increased levels of RANK-c transcript variant expression while ER-negative MDA-MB-231 and SKBR3 presented relatively with the lower. Based on the notion that RANK-c inhibits RANK-induced NF-kappaB activation, we sought to determine NFkappaB target gene expression (TNFAIP3, ICAM1, RANKL, CXCL1) after serum and TNF-alpha stimulation in MCF7 and MDA-MB-231 cells stably transduced to express RANK-c isoform. In ER-positive MCF7-RANK-c expressing cells NF-kappaB target genes were upregulated after cell stimulation, while in ER-negative MDA-MB231-RANK-c expressing cells the induction of NF-kappaB regulated genes was abrogated. In addition, RANK-c expressing MDA-MB-231 cells presented with a reduced capacity to form colonies in soft agar, migrate through transwell and invade into matrigel, in comparison to control MDA-MB-231 cells. On the other hand, in ER-positive MCF7-RANK-c expressing cells RANK-c expression was unable to affect proliferation and migration, in contrast to MDAMB-231-RANK-c cells. Conclusions: Our data indicate that RANK-c expression in ER-negative breast cancer cells suppresses aggressive properties related to metastatic colonization and inhibits stimuli-dependent NF-kappaB activation. Acknowledgements: CS was funded by the State Scholarships Foundation “IKY Fellowships of Excellence for Postgraduate Studies in Greece-Siemens Programme” (SR 229101). Disclosure of Interest: No significant relationships. P063 Whole exome sequencing revealed a novel 1-bp PALB2 deletion mutation (D434fs) in a breast cancer patient with a BRCA1 variant of uncertain clinical significance. A. Peeters1, C. Van Heerden3, M. Kotze2 *. 1Division of Anatomical Pathology, Faculty of Medicine and Health Sciences, Stellenbosch University, Tygerberg, South Africa, 2Division of Chemical Pathology, Faculty of Medicine and Health Sciences, Stellenbosch University and the National Health Laboratory Service, Tygerberg Hospital, Tygerberg, South Africa, 3Central Analytical Facilities, Faculty of Science, Stellenbosch University, Stellenbosch, South Africa Aim: BRCA1/2 full gene screening performed in a 46 year old breast cancer patient, resulted in the detection of a missense mutation classified as a variant of uncertain clinical significance at a commercial laboratory. BRCA1 S1040N (c.3119G > A) was considered insufficient to explain the relatively strong family history of cancer reported by the patient. Comprehensive whole exome sequencing (WES) was performed in this study to identify the causative mutation in the family. Methods: Genomic DNA was extracted from peripheral blood and sequenced on the Ion Proton platform. Raw reads were mapped to GRCh37 and assembled into a BAM file with the Torrent Suite software. VCF files were generated at low stringency with the Torrent Server Variant Caller and analysed on the GeneTalk platform (www.gene-talk.de). Only functional variants with a minimum coverage of 15x were filtered in and prioritised against a list of known cancer driver genes. Potentially disease causing variants were verified with the Integrative Genomics Viewer. Finally, the
Poster Abstracts I / The Breast 32S1 (2017) S22–S77
P061 Plasma Malondialdehyde and Ischemia-modified Albumin levels in breast cancer patients before and after adjuvant chemotherapy T.O. Topcu1 *, H. Kavgaci2, F. Ozdemir2, A. Mentese3, A. Orem3, F. Aydin2 . 1Division of Medical Oncology, Medeniyet University Goztepe Training and Research Hospital, Istanbul, Turkey, 2Division of Medical Oncology, School of Medicine, Karadeniz Technical University, Trabzon, Turkey, 3 Department of Biochemistry, School of Medicine, Karadeniz Technical University, Trabzon, Turkey Aims: Breast cancer is the most common cancer among women. Oxidative stress plays an important role in carcinogenesis. Oxidative stress affects cell metabolism, signaling pathways, gene expression, cell proliferation and apoptosis. The aim of this study was to investigate plasma levels of malondialdehyde (MDA) and ischemiamodified albumin (IMA), novel oxidative stress biomarkers, and to assess the effect of anthracycline-based chemotherapy on plasma MDA and IMA in patients with operable breast cancer. Methods: Fifty-five patients with operable breast cancer and 35 agematched healthy controls were enrolled. Levels of MDA and IMA were investigated before and after adjuvant chemotherapy. Basal levels ( pre-chemotherapy) of MDA and IMA in patients were compared with those in healthy controls and with patient levels after 3 cycles of chemotherapy. Levels of MDA and IMA were determined using the ELISA method. Results: MDA levels were significantly higher in patients than in the controls ( p < 0.001) are shown in Table 1. IMA levels were also higher in patients, but the difference was not significant ( p: 0.12). Postchemotherapy MDA levels were lower than basal levels ( p < 0.001). No difference was determined between basal and post-chemotherapy IMA levels. We determined a significant correlation between prechemotherapy CA 15-3 and MPV and post-chemotherapy MDA levels ( p < 0.001 r: 0.512 and p: 0.006, r: 0.382, respectively). Table 2 MDA, İMA levels in pre-chemotherapy and control groups Variable
Prechemotherapy
MDA IMA
0.28±0.10 0.53±0.90
Controls
P
0.14±0.66 0.50±0.90
<0.001 0.12
Conclusions: The oxidative-antioxidant balance is impaired in breast cancer patients. In conclusion, we observed elevated MDA levels in our breast cancer patients. This may indicate an oxidative imbalance involving increased oxidative agents and decreased anti-oxidant defense. Our study shows that this imbalance causes progression of operable breast cancer. Further chemotherapy and close monitoring should be considered in cases of breast cancer with increased MDA levels after adjuvant chemotherapy. Elevated MDA levels after adjuvant chemotherapy may indicate drug resistance. High plasma MDA levels before and after adjuvant chemotherapy appear to be a poor prognostic factor for breast cancer patients independent of tumor pathology type. This study represents the first investigation of IMA levels in these patients. Increased MDA levels are more accurate than plasma IMA levels in showing oxidative imbalance in operated breast cancer patients. Disclosure of Interest: No significant relationships. P062 RANK-c isoform inhibits stimuli-dependent NF-kappaB signaling and aggressiveness of ER-negative breast cancer cells C. Sirinian, A. Papanastasiou, H. Kalofonos*. Molecular and Clinical Oncology Laboratory, Division of Oncology, Department of Medicine, University of Patras, Patras, Greece Aims: We have previously shown that RANK-c is an isoform of RANK receptor (TNFRSF11A) produced through alternative splicing,
affecting RANK-dependent NF-kappaB activation. In this study we aimed to elucidate differences of RANK-c expression and function between estrogen receptor (ER) positive and ER-negative breast cancer cells. Methods: A panel of human breast cancer cell lines (MCF7, T47D, SKBR3, BT474, MDA-MB-231) was employed for RANK-c mRNA expression and functional analyses. Expression analysis was done by real time PCR on RNA from breast cancer cell lines and transcript specific primers. Through transient transfection and luciferase assays we evaluated RANK-c contribution on NF-kB activation. Stable cell lines were generated for isoform functional characterization through MTT assay, wound healing, transwell and matrigel assays. Results: Estrogen receptor-positive cell lines (MCF7 and T47D) presented with increased levels of RANK-c transcript variant expression while ER-negative MDA-MB-231 and SKBR3 presented relatively with the lower. Based on the notion that RANK-c inhibits RANK-induced NF-kappaB activation, we sought to determine NFkappaB target gene expression (TNFAIP3, ICAM1, RANKL, CXCL1) after serum and TNF-alpha stimulation in MCF7 and MDA-MB-231 cells stably transduced to express RANK-c isoform. In ER-positive MCF7-RANK-c expressing cells NF-kappaB target genes were upregulated after cell stimulation, while in ER-negative MDA-MB231-RANK-c expressing cells the induction of NF-kappaB regulated genes was abrogated. In addition, RANK-c expressing MDA-MB-231 cells presented with a reduced capacity to form colonies in soft agar, migrate through transwell and invade into matrigel, in comparison to control MDA-MB-231 cells. On the other hand, in ER-positive MCF7-RANK-c expressing cells RANK-c expression was unable to affect proliferation and migration, in contrast to MDAMB-231-RANK-c cells. Conclusions: Our data indicate that RANK-c expression in ER-negative breast cancer cells suppresses aggressive properties related to metastatic colonization and inhibits stimuli-dependent NF-kappaB activation. Acknowledgements: CS was funded by the State Scholarships Foundation “IKY Fellowships of Excellence for Postgraduate Studies in Greece-Siemens Programme” (SR 229101). Disclosure of Interest: No significant relationships. P063 Whole exome sequencing revealed a novel 1-bp PALB2 deletion mutation (D434fs) in a breast cancer patient with a BRCA1 variant of uncertain clinical significance. A. Peeters1, C. Van Heerden3, M. Kotze2 *. 1Division of Anatomical Pathology, Faculty of Medicine and Health Sciences, Stellenbosch University, Tygerberg, South Africa, 2Division of Chemical Pathology, Faculty of Medicine and Health Sciences, Stellenbosch University and the National Health Laboratory Service, Tygerberg Hospital, Tygerberg, South Africa, 3Central Analytical Facilities, Faculty of Science, Stellenbosch University, Stellenbosch, South Africa Aim: BRCA1/2 full gene screening performed in a 46 year old breast cancer patient, resulted in the detection of a missense mutation classified as a variant of uncertain clinical significance at a commercial laboratory. BRCA1 S1040N (c.3119G > A) was considered insufficient to explain the relatively strong family history of cancer reported by the patient. Comprehensive whole exome sequencing (WES) was performed in this study to identify the causative mutation in the family. Methods: Genomic DNA was extracted from peripheral blood and sequenced on the Ion Proton platform. Raw reads were mapped to GRCh37 and assembled into a BAM file with the Torrent Suite software. VCF files were generated at low stringency with the Torrent Server Variant Caller and analysed on the GeneTalk platform (www.gene-talk.de). Only functional variants with a minimum coverage of 15x were filtered in and prioritised against a list of known cancer driver genes. Potentially disease causing variants were verified with the Integrative Genomics Viewer. Finally, the