- Email: [email protected]
HO-1 down-regulation increases the efficacy of BRAFV600E inhibition-based therapy in primary melanoma cells
S64
D. Rossin et al. / Free Radical Biology and Medicine 108 (2017) S18–S107
P-135
HO-1 down-regulation increases the efficacy of BRAFV600E inhibition-based therapy in primary melanoma cells Anna Lisa Furfaro 1, Gabriella Pietra 2,3, Irene Cossu 1, Umberto M. Marinari 2, Lorenzo Moretta 4, Maria Cristina Mingari 2,3, Maria A. Pronzato 2, Mariapaola Nitti 2 1
Giannina Gaslini Institute, IRCCS, Genoa, Italy Department of Experimental Medicine, University of Genoa, Genoa, Italy 3 Immunologia AOU S. Martino-IST, IRCCS, Genoa, Italy 4 Bambino Gesù Children's Hospital, IRCCS, Rome, Italy 2
Keywords: HO-1; melanoma; cell resistance; NK; oxidative stress
Heme oxygenase 1 (HO-1) plays a key role in maintaining cell redox balance. Under stress conditions, HO-1 is up-regulated and generates bilirubin, ferritin and carbon monoxide, with antioxidant, antiapoptotic and anti-inflammatory properties [Jozkowicz et al., 2007]. HO-1 induction favors cancer progression [Furfaro et al., 2016] and its involvement in tumor resistance to therapy [Was et al., 2006] and immune-escape has been highlighted in melanoma-bearing mice [Di Biase et al., 2016]. In this work, the role of HO-1 in melanoma cell resistance to Vemurafenib/PLX4032, a selective inhibitor of mutant BRAFV600 has been investigated, as well as HO-1 involvement in natural killer (NK)-mediated killing. BRAFV600E mutant primary melanoma cells isolated in our lab have been treated for 24 h with 1 μM PLX4032. The treatment reduced viability (-23%), increased HO-1 mRNA level of two-fold, and decreased the ability of IL-15 activated NK cells to degranulate in response to PLX4032-treated cells, when compared to untreated melanoma cells. HO-1 silencing increased PLX4032 efficacy further reducing cell viability to 47% in comparison to cells treated with PLX4032 alone and restored the degranulation potential of NK. Thus, we hypothesize that HO-1 inhibition can effectively improve the efficacy of mutant-BRAF inhibitors and favors NK-depending killing of PLX4032-treated melanoma cells. E-mail address: [email protected] (A.L. Furfaro) Acknowledgements
Funding was provided by MIUR-PRIN20125S38FA and Genoa University. http://dx.doi.org/10.1016/j.freeradbiomed.2017.04.220
P-136
Acute effect of Thai Chi on marker of oxidative stress and flow-mediated dilation among healthy young and elderly volunteers Nor Fadila Kasim 1,2, Sarah Aldred 1, Jet Veldhuijzen van Zanten 1 1 2
University of Birmingham, United Kingdom Sultan Idris Education University, Malaysia
Keywords: Tai Chi; oxidative stress; inflammation
Tai Chi is an ancient exercise originated from China. The slow movements of Tai Chi are not thought to evoke an increase in heart rate above 60% HRM, and yet Tai Chi has been found to improve vascular health. We are interested in the response to a single session of Tai Chi, as a mild physical stressor. The acute response to exercise is very important as a stimulus for adaptation, but to our knowledge, no previous studies have assessed the acute response to Tai Chi. The aim of this study was to investigate the response to a single session of Tai Chi. Blood markers of oxidative stress (lipid peroxidation, antioxidant capacity) and inflammation (IL-6) were assessed along with flow-mediated dilation (FMD) in young (1825years old) and elderly participants (65–75 years old). Participants visited the laboratory twice to undertake Tai Chi or a control visit. Blood withdrawal and FMD assessment were performed every hour, for 4 consecutive hours. Inflammation at baseline was increased in older participants, compared to young and MDA and IL-6 increased immediately after Tai Chi in both groups. Antioxidant capacity increased immediately and post one hour after Tai Chi in both groups. A single bout of Tai Chi was seen to promote cytokine release and increased antioxidant capacity, and may have a beneficial effect in improving human vasculature via these mechanisms in both old and young. E-mail address: [email protected] (N.F. Kasim) http://dx.doi.org/10.1016/j.freeradbiomed.2017.04.221
P-137
Expression patterns of peroxiredoxins in the rat bone and their changes after ovariectomy—an implication in aging? Jose Rodrigo Godoy Berthet Department of Biomedical Sciences, Ross University School of Veterinary Medicine, St. Kitts and Nevis, West Indies Keywords: Peroxiredoxins; bone; immunohistochemistry
Peroxiredoxins (Prxs, 20–30 kDa) belong to the thioredoxin protein family that is characterized by a common structural motif, the thioredoxin fold, and the presence of one or two cysteines in their active site. These proteins are recognized as key molecules in redox signaling and are expressed in various tissues of mice and humans. The growing evidence for a role of oxidative stress in bone pathologies, prompted us to systematically analyze the expression patterns of Prxs (1–6) in the femur of rats and their changes after ovariectomy. All analyzed Prxs were abundantly expressed in different cell types of the bone of sham operated rats. Strong signals for Prx1 and 3 were observed in osteocytes’ lacunae, osteoblasts, bone lining cells, and in the epiphyseal cartilage. Both Prx1 and Prx3 showed a characteristic staining pattern in the canalicular system of the bone. Ovariectomy in rats induced downregulation of Prxs in almost all cell types of the bone and bone marrow compartment. Because these redox proteins are crucial not only for maintaining a reduced environment, but also for many other cellular processes, the results shown here might have an implication in diseases associated with estrogen deficiency, for instance, osteoporosis and the immune response in aging. E-mail address: [email protected] http://dx.doi.org/10.1016/j.freeradbiomed.2017.04.222
D. Rossin et al. / Free Radical Biology and Medicine 108 (2017) S18–S107
P-135
HO-1 down-regulation increases the efficacy of BRAFV600E inhibition-based therapy in primary melanoma cells Anna Lisa Furfaro 1, Gabriella Pietra 2,3, Irene Cossu 1, Umberto M. Marinari 2, Lorenzo Moretta 4, Maria Cristina Mingari 2,3, Maria A. Pronzato 2, Mariapaola Nitti 2 1
Giannina Gaslini Institute, IRCCS, Genoa, Italy Department of Experimental Medicine, University of Genoa, Genoa, Italy 3 Immunologia AOU S. Martino-IST, IRCCS, Genoa, Italy 4 Bambino Gesù Children's Hospital, IRCCS, Rome, Italy 2
Keywords: HO-1; melanoma; cell resistance; NK; oxidative stress
Heme oxygenase 1 (HO-1) plays a key role in maintaining cell redox balance. Under stress conditions, HO-1 is up-regulated and generates bilirubin, ferritin and carbon monoxide, with antioxidant, antiapoptotic and anti-inflammatory properties [Jozkowicz et al., 2007]. HO-1 induction favors cancer progression [Furfaro et al., 2016] and its involvement in tumor resistance to therapy [Was et al., 2006] and immune-escape has been highlighted in melanoma-bearing mice [Di Biase et al., 2016]. In this work, the role of HO-1 in melanoma cell resistance to Vemurafenib/PLX4032, a selective inhibitor of mutant BRAFV600 has been investigated, as well as HO-1 involvement in natural killer (NK)-mediated killing. BRAFV600E mutant primary melanoma cells isolated in our lab have been treated for 24 h with 1 μM PLX4032. The treatment reduced viability (-23%), increased HO-1 mRNA level of two-fold, and decreased the ability of IL-15 activated NK cells to degranulate in response to PLX4032-treated cells, when compared to untreated melanoma cells. HO-1 silencing increased PLX4032 efficacy further reducing cell viability to 47% in comparison to cells treated with PLX4032 alone and restored the degranulation potential of NK. Thus, we hypothesize that HO-1 inhibition can effectively improve the efficacy of mutant-BRAF inhibitors and favors NK-depending killing of PLX4032-treated melanoma cells. E-mail address: [email protected] (A.L. Furfaro) Acknowledgements
Funding was provided by MIUR-PRIN20125S38FA and Genoa University. http://dx.doi.org/10.1016/j.freeradbiomed.2017.04.220
P-136
Acute effect of Thai Chi on marker of oxidative stress and flow-mediated dilation among healthy young and elderly volunteers Nor Fadila Kasim 1,2, Sarah Aldred 1, Jet Veldhuijzen van Zanten 1 1 2
University of Birmingham, United Kingdom Sultan Idris Education University, Malaysia
Keywords: Tai Chi; oxidative stress; inflammation
Tai Chi is an ancient exercise originated from China. The slow movements of Tai Chi are not thought to evoke an increase in heart rate above 60% HRM, and yet Tai Chi has been found to improve vascular health. We are interested in the response to a single session of Tai Chi, as a mild physical stressor. The acute response to exercise is very important as a stimulus for adaptation, but to our knowledge, no previous studies have assessed the acute response to Tai Chi. The aim of this study was to investigate the response to a single session of Tai Chi. Blood markers of oxidative stress (lipid peroxidation, antioxidant capacity) and inflammation (IL-6) were assessed along with flow-mediated dilation (FMD) in young (1825years old) and elderly participants (65–75 years old). Participants visited the laboratory twice to undertake Tai Chi or a control visit. Blood withdrawal and FMD assessment were performed every hour, for 4 consecutive hours. Inflammation at baseline was increased in older participants, compared to young and MDA and IL-6 increased immediately after Tai Chi in both groups. Antioxidant capacity increased immediately and post one hour after Tai Chi in both groups. A single bout of Tai Chi was seen to promote cytokine release and increased antioxidant capacity, and may have a beneficial effect in improving human vasculature via these mechanisms in both old and young. E-mail address: [email protected] (N.F. Kasim) http://dx.doi.org/10.1016/j.freeradbiomed.2017.04.221
P-137
Expression patterns of peroxiredoxins in the rat bone and their changes after ovariectomy—an implication in aging? Jose Rodrigo Godoy Berthet Department of Biomedical Sciences, Ross University School of Veterinary Medicine, St. Kitts and Nevis, West Indies Keywords: Peroxiredoxins; bone; immunohistochemistry
Peroxiredoxins (Prxs, 20–30 kDa) belong to the thioredoxin protein family that is characterized by a common structural motif, the thioredoxin fold, and the presence of one or two cysteines in their active site. These proteins are recognized as key molecules in redox signaling and are expressed in various tissues of mice and humans. The growing evidence for a role of oxidative stress in bone pathologies, prompted us to systematically analyze the expression patterns of Prxs (1–6) in the femur of rats and their changes after ovariectomy. All analyzed Prxs were abundantly expressed in different cell types of the bone of sham operated rats. Strong signals for Prx1 and 3 were observed in osteocytes’ lacunae, osteoblasts, bone lining cells, and in the epiphyseal cartilage. Both Prx1 and Prx3 showed a characteristic staining pattern in the canalicular system of the bone. Ovariectomy in rats induced downregulation of Prxs in almost all cell types of the bone and bone marrow compartment. Because these redox proteins are crucial not only for maintaining a reduced environment, but also for many other cellular processes, the results shown here might have an implication in diseases associated with estrogen deficiency, for instance, osteoporosis and the immune response in aging. E-mail address: [email protected] http://dx.doi.org/10.1016/j.freeradbiomed.2017.04.222