Light-emitting diode irradiation induces AKT/mTOR-mediated apoptosis in human pancreatic cancer cells and xenograft mouse model

Reviewing the efficiency of photobiomodulation therapy in oncological treatment

The aim of the present systematic review is to evaluate the effects of different photobiomodulation therapy (PBMT) approaches in oncological treatment practices. The review follows the PRISMA guidelines. Specifically, the review is composed of laser PBMT and LED PBMT. A total of 23 studies were included, 14 investigating laser PBMT and 9 examining LED PBMT. In vitro studies demonstrated laser PBMT's potential to induce apoptosis and cytotoxicity in various cancer cell lines while enhancing sensitivity to chemotherapeutics and natural compounds. However, some studies highlighted divergent effects between in vitro (promoted proliferation) and in vivo xenograft models (slowed tumor growth) for certain laser wavelengths. LED PBMT studies showed blue light inhibited melanoma and pancreatic cancer cell growth, potentially via ROS generation, while red light raised concerns about enhancing oral cancer invasiveness. Both modalities mitigated treatment side effects like oral mucositis, xerostomia, peripheral neuropathy, and improved quality of life. While promising, the outcomes varied based on light parameters, cancer type, and experimental setting, necessitating further optimization of PBMT protocols through well-designed studies to establish long-term safety and efficacy across clinical scenarios.

Visible light accelerates skin wound healing and alleviates scar formation in mice by adjusting STAT3 signaling

During the wound healing process, the activation of signal transducer and activator of transcription 3 (STAT3) is considered crucial for the migration and proliferation of epithelial cells, as well as for establishing the inflammatory environment. However, an excessive STAT3 activation aggravates scar formation. Here we show that 450 nm blue light and 630 nm red light can differentially regulate the phosphorylation of STAT3 (p-STAT3) and its downstream cytokines in keratinocytes. Further mechanistic studies reveal that red light promotes wound healing by activating the PI3 kinase p110 beta (PI3Kβ)/STAT3 signaling axis, while blue light inhibits p-STAT3 at the wound site by modulating cytochrome c-P450 (CYT-P450) activity and reactive oxygen species (ROS) generation. In a mouse scar model, skin wound healing can be significantly accelerated with red light followed by blue light to reduce scar formation. In summary, our study presents a potential strategy for regulating epithelial cell p-STAT3 through visible light to address skin scarring issues and elucidates the underlying mechanisms.

Blue light photobiomodulation induced osteosarcoma cell death by facilitating ferroptosis and eliciting an incomplete tumor cell stress response

To investigate the potential of blue light photobiomodulation (PBM) in inducing ferroptosis, a novel form of regulated cell death, in OS cells, considering its known effectiveness in various cancer models. In this investigation, we exposed human OS cell lines, HOS and MG63, to different wavelengths (420, 460 and 480 nm) of blue light at varying irradiances, and examined cellular responses such as viability, apoptosis, levels of reactive oxygen species (ROS), and mitochondrial membrane potential (MMP). Transcriptome sequencing was employed to unravel the molecular mechanisms underlying blue light-induced effects, with validation via quantitative real-time PCR (qRT-PCR). Our findings revealed a wavelength- and time-dependent decrease in cell viability, accompanied by increased apoptosis and oxidative stress. Transcriptomic analysis identified differential expression of genes associated with ferroptosis, oxidative stress, and iron metabolism, further validated by qRT-PCR. These results implicated ferroptosis as a significant mechanism in the blue light-induced death of OS cells, potentially mediated by ROS generation and disruption of iron homeostasis. Also, An incomplete stress response was observed in MG63 cells induced by blue light exposure. Hence, blue light PBM holds promise as a therapeutic approach in OS clinical investigations; however, additional exploration of its underlying mechanisms remains imperative.

Blue light photobiomodulation induced apoptosis by increasing ROS level and regulating SOCS3 and PTEN/PI3K/AKT pathway in osteosarcoma cells

Blue light photobiomodulation (PBM) has attracted great attention in diminishing proliferation and inducing death of cancer cells recently. Osteosarcoma (OS) primarily occurring in children and adolescents, the limitations of drug resistance and limb salvage make it urgent to develop and identify new adjuvant therapeutic strategies. In this work, we attempted to research the anticancer effects and biological mechanisms of blue light PBM in human OS MG63 cells. The effects of various blue light parameters on MG63 cells indicated that suppressed cell proliferation and cell migration, induced cell apoptosis which are experimentally assessed using multiple assays including CCK, LDH, wound healing assay and Hoechst staining. Concurrently, the increases of ROS level and the inhibition of PI3K and AKT expression were identified under high-dose blue light PBM in MG63 cells. Meanwhile, SOCS3 is a major inducible anti-tumor molecule, we also found that blue light LED substantially promoted its expression. Thus, this study proposed that bule light PBM may be a hopeful therapeutic approach in OS clinical treatment in the future.

Effect of blue light on the cell viability of A549 lung cancer cells and investigations into its possible mechanism

Blue light has attracted extensive attention as a new potential cancer therapy. Recent studies have indicated that blue light has a significant inhibition effect on A459 cells. However, the effect of light parameters on the treatment of A549 cells and the mechanism of how blue light made the effect was still unclear. This study aimed to investigate A549 cells responses to blue light with varying irradiance and dose-dense, and tried to find out the mechanism of the effects blue light made. The results suggested that the responses of A549 cells to blue light with different irradiance and dose-dense were different and the decrease of cell viability reached saturation when the irradiance reached 3 mW/cm2 and the dose-dense reached 3.6 J/cm2 . It was assumed that blue light suppressed PI3K/AKT pathway and promoted the expression of JNK and p53 to affect the proliferation of A549 cells.

Exploring the Effects of 630 nm Wavelength of Light-Emitting Diode Irradiation on the Proliferation and Migration Ability of Human Biceps Tendon Fibroblast Cells

Background

Light-emitting diode (LED)-based photobiomodulation is used as an inducer of cell regeneration. Although numerous in vitro and in vivo orthopedic studies have been conducted, the ideal LED wavelength range for tendon healing has not yet been determined. This study, thus, focused on the effects of LED of a 630 nm wavelength on the cell viability, proliferation, and migration of human biceps tendon fibroblast cells.

Methods

Human tendon fibroblast cell culture was performed using the biceps tendon of patients who had undergone biceps tenodesis. Human biceps tendon fibroblasts from two patients (male, aged 42 and 69 years) were isolated and cultured. The cell type was confirmed by a morphological analysis and using tendon and fibroblast specific markers. They were then split into three groups, with each receiving a different irradiation treatment: no LED treatment (control), 630 nm LED, and 630 nm + 880 nm LED for 20 minutes each. After the LED treatment, cell viability, proliferation, and migration assays were performed, and the results were compared between the groups.

Results

Twenty-four hours after LED treatment, cell viability and proliferation were significantly increased in the 630 nm LED and 630 nm + 880 nm LED treatment groups compared to that in the control group (p < 0.05). Under the same conditions, compared with the control group, the 630 nm LED alone treatment group showed a 3.06 ± 0.21 times higher cell migration rate (p < 0.05), and the 630 nm + 880 nm LED combination treatment group showed a 2.88 ± 0.20 times higher cell migration rate (p < 0.05) in three-dimensional migration assay.

Conclusions

In human tendon fibroblast cells, 20 minutes of LED treatment at 630 nm and 630 nm + 880 nm exhibited significant effects on cell proliferation and migration. Our findings suggest the potential of LED therapy as an adjuvant treatment for tendon healing, and hence, further research is warranted to standardize the various parameters to further develop and establish this as a reliable treatment regimen.

Progress of phototherapy for osteosarcoma and application prospect of blue light photobiomodulation therapy

Osteosarcoma (OS) is the most common primary malignant bone tumor that mainly affects the pediatric and adolescent population; limb salvage treatment has become one of the most concerned and expected outcomes of OS patients recently. Phototherapy (PT), as a novel, non-invasive, and efficient antitumor therapeutic approach including photodynamic therapy (PDT), photothermal therapy (PTT), and photobiomodulation therapy (PBMT), has been widely applied in superficial skin tumor research and clinical treatment. OS is the typical deep tumor, and its phototherapy research faces great limitations and challenges. Surprisingly, pulse mode LED light can effectively improve tissue penetration and reduce skin damage caused by high light intensity and has great application potential in deep tumor research. In this review, we discussed the research progress and related molecular mechanisms of phototherapy in the treatment of OS, mainly summarized the status quo of blue light PBMT in the scientific research and clinical applications of tumor treatment, and outlooked the application prospect of pulsed blue LED light in the treatment of OS, so as to further improve clinical survival rate and prognosis of OS treatment and explore corresponding cellular mechanisms.

The potential roles of p53 signaling reactivation in pancreatic cancer therapy

Globally, pancreatic cancer (PC) is a common and highly malignant gastrointestinal tumor that is characterized by an insidious onset and ready metastasis and recurrence. Over recent decades, the incidence of PC has been increasing on an annual basis; however, the pathogenesis of this condition remains enigmatic. PC is not sensitive to radio- or chemotherapy, and except for early surgical resection, there is no curative treatment regime; consequently, the prognosis for patients with PC is extremely poor. Transcription factor p53 is known to play key roles in many important biological processes in vertebrates, including normal cell growth, differentiation, cell cycle progression, senescence, apoptosis, metabolism, and DNA damage repair. However, there is a significant paucity of basic and clinical studies to describe how p53 gene mutations or protein dysfunction facilitate the occurrence, progression, invasion, and resistance to therapy, of malignancies, including PC. Herein, we describe the involvement of p53 signaling reactivation in PC treatment as well as its underlying molecular mechanisms, thereby providing useful insights for targeting p53-related signal pathways in PC therapy.