Evaluation of Biological Activity of Different Wavelengths of Low-Level Laser Therapy on the Cancer Prostate Cell Line Compared With Cisplatin.

Introduction: Cancer is one of the most important problems in the world. Low-level laser therapy (LLLT) has been emerged as a new approach, having both stimulation and inhibition effects on cellular function. The goal of this study was to analyze and compare the different concentrations of cisplatin and wavelengths of laser therapy on the LnCap cell lines. Methods: LnCap cells were cultured and treated with different concentrations of cisplatin (0.1, 0.4, 0.8, 1.2 and 2 µg/mL for 24 hours) and wavelengths of laser therapy (610, 630 and 810 nm) (0.45 J/cm2) separately. The viability of cells was examined by MTT assay and IC50 was also calculated. Furthermore, a combination of cisplatin IC50 (24 hours) and different wavelengths of the laser was examined. Results: The results of this study showed that 2 µg/mL of cisplatin has the most significant reduction effect on the cell viability of the LnCap cell line. Cisplatin decreased the viability of cells in a dose-dependent manner. Moreover, IC50 of cisplatin was 1.24 µg/mL. On the other hand, LLLT with wavelengths of 610, 630 and 810 nm did not show notable biological effects on cell viability. Conclusion: As known, cisplatin has the capability to reduce the viability of LnCap cell lines. However, LLLT cannot be a remarkable option for the treatment of prostate cancer. Therefore, although laser therapy showed praiseful therapeutic activity against some cancer cell lines, in this study the results indicated that defined laser wavelengths had no inhibitory effects against the prostate cancer cell line.