Different Effects of Low-Level Laser Therapy on the Proliferation of HT29 Cells in Culture and Xenograft Models

Najmeh Malekzadeh Gonabadi; Mehdi Shamsara; Dor Mohammad Kordi Tamandani; Sahar Shojaei; Seyed Mehdi Alavi

doi:10.34172/jlms.2023.31

Different Effects of Low-Level Laser Therapy on the Proliferation of HT29 Cells in Culture and Xenograft Models

J Lasers Med Sci. 2023 Aug 30:14:e31. doi: 10.34172/jlms.2023.31. eCollection 2023.

Authors

Najmeh Malekzadeh Gonabadi¹, Mehdi Shamsara², Dor Mohammad Kordi Tamandani¹, Sahar Shojaei³, Seyed Mehdi Alavi⁴

Affiliations

¹ Department of Biology, University of Sistan and Baluchestan, Zahedan, Iran.
² Department of Animal Biotechnology, National Institute for Genetic Engineering and Biotechnology, Tehran, Iran.
³ Middle East Gene and Cell Therapy Company, Tehran, Iran.
⁴ Department of Plant Biotechnology, National Institute for Genetic Engineering and Biotechnology, Tehran, Iran.

Abstract

Introduction: Different kinds of treatments have been developed to fight cancers. Low-level laser therapy (LLLT), also known as photobiomodulation therapy (PBMT), is a low-power monochromatic and coherent light that has been used successfully for healing injuries and combating malignancies. However, there are concerns about the application of LLLT to cancers due to the increased proliferation of some cancer cells after LLLT. Methods: This study investigated the effects of 650 nm and 870 nm lasers on the proliferation of HT29 colorectal cancer cell lines in vitro and in vivo. Results: The results showed that the laser with a wavelength of 870 nm did not meaningfully alter the proliferation of cultured cells. However, cell proliferation was promoted when the laser was applied within a wavelength of 650 nm. Treatment of HT29-derived tumors in nude mice with the 650 nm laser resulted in the decline of the tumor progression rate compared to controls. This result was inconsistent with the proliferative effects of the laser on the cultured cells. Conclusion: Cell behavior in response to LLLT might be different between cell culture and xenograft models.

Keywords: Cell proliferation; Colorectal cancer; Low-level laser therapy; Photobiomodulation.