Gabriela Klein Couto1, Bruna Silveira Pacheco1, Victoria Mascarenhas Borba1, João Carlos Rodrigues Junior1, Thaís Larré Oliveira1, Natália Vieira Segatto1, Fabiana Kommling Seixas1, Thiago V Acunha2, Bernardo Almeida Iglesias3, Tiago Collares4. 1. Molecular and Cellular Oncology Research Group, Cancer Biotechnology Laboratory, Technological Development Center, Federal University of Pelotas, Pelotas, Brazil. 2. Laboratory of Bioinorganic and Porphyrinoid Materials, Chemistry Department, Federal University of Santa Maria, Santa Maria, Brazil. 3. Laboratory of Bioinorganic and Porphyrinoid Materials, Chemistry Department, Federal University of Santa Maria, Santa Maria, Brazil. Electronic address: bernardopgq@gmail.com. 4. Molecular and Cellular Oncology Research Group, Cancer Biotechnology Laboratory, Technological Development Center, Federal University of Pelotas, Pelotas, Brazil. Electronic address: collares.t@gmail.com.
Abstract
Photodynamic therapy (PDT) is an expanding treatment modality due to its minimally invasive localized activity and few adverse effects. This therapy requires photosensitive compounds, which have high sensitivity to light exposure. Thus, in this work, the in vitro antitumor activity of meso-tetra(3- and 4-pyridyl)porphyrins (3-TPyP and 4-TPyP) in metastatic melanoma cell (WM1366 line) and non-tumoral Ovarian lineage Chinese Hamister (CHO) was evaluated using photodynamic process. Cell viability tests, molecular docking, annexin V, confocal microscopy and qRT-PCR were performed. Our results show that both porphyrins inhibited the viability of metastatic melanoma cells when exposed to light and did not alter viability in the dark. In addition, they did not demonstrate cytotoxicity in non-tumor cells. Molecular coupling demonstrated platinum porphyrin affinity for the N-terminal region of APO B-100, LDL receptor, and therefore of the cells under study. Genes such as Caspase 3 and 9, P21, Bax / BCL2, MnSod and GSH showed increased expression. For meta isomer 3-PtTPyP treatment, caspase-9 and caspase-3 expression levels showed a 4.89 and 3.23-fold increase, respectively, while for the para isomer 4-PtTPyP, this change was 3.77 and 12.16-fold, respectively. We also observed an upregulated expression of p21, a protein well-known by its action in cell cycle arrest in a p53-dependent manner. Conclusion: 3-PtTPyP and 4-PtTPyP demonstrated antitumor effect on WM1366 cells, inducing apoptosis and significant alteration of cell cytoskeleton actin. Our work shows that platinum(II) porphyrins may be promising photosensitizers for the treatment of metastatic melanoma by PDT.
Photodynamic therapy (PDT) is an expanding treatment modality due to its minimally invasive localized activity and few adverse effects. This therapy requires photosensitive compounds, which have high sensitivity to light exposure. Thus, in this work, the in vitro antitumor activity of meso-tetra(3- and 4-pyridyl)porphyrins (3-TPyP and 4-TPyP) in metastatic melanoma cell (WM1366 line) and non-tumoral Ovarian lineage Chinese Hamister (CHO) was evaluated using photodynamic process. Cell viability tests, molecular docking, annexin V, confocal microscopy and qRT-PCR were performed. Our results show that both porphyrins inhibited the viability of metastatic melanoma cells when exposed to light and did not alter viability in the dark. In addition, they did not demonstrate cytotoxicity in non-tumor cells. Molecular coupling demonstrated platinumporphyrin affinity for the N-terminal region of APO B-100, LDL receptor, and therefore of the cells under study. Genes such as Caspase 3 and 9, P21, Bax / BCL2, MnSod and GSH showed increased expression. For meta isomer 3-PtTPyP treatment, caspase-9 and caspase-3 expression levels showed a 4.89 and 3.23-fold increase, respectively, while for the para isomer 4-PtTPyP, this change was 3.77 and 12.16-fold, respectively. We also observed an upregulated expression of p21, a protein well-known by its action in cell cycle arrest in a p53-dependent manner. Conclusion:3-PtTPyP and 4-PtTPyP demonstrated antitumor effect on WM1366 cells, inducing apoptosis and significant alteration of cell cytoskeleton actin. Our work shows that platinum(II) porphyrins may be promising photosensitizers for the treatment of metastatic melanoma by PDT.