Effects of photobiomodulation in relation to HeLa Kyoto tumor cells exposed to ionizing radiation

The effect of photobiomodulation on the radiosensitivity of cancer cells: a literature review

The goal of radiotherapy (RT) in cancer treatment is to destroy tumor tissue while preserving nearby healthy tissue. However, RT often causes adverse effects that significantly impact patients' quality of life. Tumor cells, which have high proliferation rates, are susceptible to radiation, especially during the G2 and mitosis phases of the cell cycle. Numerous studies have explored ways to enhance the Radiosensitivity of tumors to make RT more effective while minimizing harm to healthy cells. This review examines the potential use of photobiomodulation (PBM) as a radiosensitizer for cancer cells to improve the effectiveness and safety of radiotherapy. A literature search was conducted in the MEDLINE/PubMed and Google Scholar databases using keywords like "PBM, low-level light therapy, cancer cells, tumor cells, radiosensitizer, and ionizing radiation." Studies meeting the inclusion criteria were reviewed and analyzed. Several studies investigated PBM as a radiosensitizer for various cancer cell lines, including HeLa, HeLa Kyoto, A431, SCC9, and Cal 27. Most of these studies found that pre-exposure of cancer cells to PBM improved the effectiveness of radiation in destroying tumor cells. PBM is a promising, affordable, and noninvasive technique that could improve cancer treatment outcomes by increasing tumor sensitivity to radiation and reducing side effects. However, more research is needed to thoroughly assess the benefits of combining PBM with RT. Clinical trial number: not applicable. Clinical trial number: not applicable.

Wavelength-dependent photobiomodulation (PBM) for proliferation and angiogenesis of melanoma tumor in vitro and in vivo

Photobiomodulation (PBM) has widely been used to effectively treat complications associated with cancer treatment, including oral mucositis, radiation dermatitis, and surgical wounds. However, the safety of PBM against cancer still needs to be validated as the effects of PBM on cancer cells and their mechanisms are unclear. The current study investigated the wavelength-dependent PBM effects by examining four different laser wavelengths (405, 532, 635, and 808 nm) on B16F10 melanoma tumor cells. In vitro tests showed that PBM with 808 nm promoted both proliferation and migration of B16F10 cells. In vivo results demonstrated that PBM with 808 nm significantly increased the relative tumor volume and promoted angiogenesis with overexpression of VEGF and HIF-1α. In addition, PBM induced the phosphorylation of factors closely related to cancer cell proliferation and tumor growth and upregulated the related gene expression. The current result showed that compared to the other wavelengths, 808 nm yielded a significant tumor-stimulating effect the malignant melanoma cancer. Further studies will investigate the in-depth molecular mechanism of PBM on tumor stimulation in order to warrant the safety of PBM for clinical cancer treatment.

Photobiomodulation therapy combined with radiotherapy in the treatment of triple-negative breast cancer-bearing mice

This work investigated the effect of photobiomodulation therapy (PBM) combined with radiotherapy (RT) on triple-negative breast cancer (TNBC)-bearing mice. Female BALB/c mice received 4 T1 cells into a mammary fat pad. Local RT was performed with a total dose of 60 Gy divided into 4 consecutive sessions of 15 Gy. For PBM, a red laser was used in three different protocols: i-) single exposure delivering 150 J.cm^-2 (24 h after the last RT session), and ii-) radiant exposure of 150 J.cm^-2 or iii-) fractionated radiant exposure of 37.5 J.cm^-2 (after each RT session). Tumor volume, complete blood cell count, clinical condition, metastasis, and survival of animals were monitored during 3 weeks post-RT. Our results demonstrated that regardless of the protocol, PBM arrested the tumor growth, improved the clinical condition, and prevented hemolytic anemia. Besides, although PBM groups have exhibited a high neutrophil:lymphocyte ratio (NLR), they decreased the number of lung metastases and enhanced mouse survival. Worthy of note, PBM should be used along with the RT sessions in higher radiant exposures, since PBM at 150 J.cm^-2 per session significantly extended the survival rate. Together, these data suggest PBM could be a potential ally to RT to fight TNBC.

Phototherapy Combined with Carbon Nanomaterials (1D and 2D) and their Applications in Cancer Therapy

Carbon-based materials have attracted research interest worldwide due to their physical and chemical properties and wide surface area, rendering them excellent carrier molecules. They are widely used in biological applications like antimicrobial activity, cancer diagnosis, bio-imaging, targeting, drug delivery, biosensors, tissue engineering, dental care, and skin care. Carbon-based nanomaterials like carbon nanotubes and graphene have drawn more attention in the field of phototherapy due to their unique properties such as thermal conductivity, large surface area, and electrical properties. Phototherapy is a promising next-generation therapeutic modality for many modern medical conditions that include cancer diagnosis, targeting, and treatment. Phototherapy involves the major administration of photosensitizers (PSs), which absorb light sources and emit reactive oxygen species under cellular environments. Several types of nontoxic PSs are functionalized on carbon-based nanomaterials and have numerous advantages in cancer therapy. In this review, we discuss the potential role and combined effect of phototherapy and carbon nanomaterials, the mechanism and functionalization of PSs on nanomaterials, and their promising advantages in cancer therapy.