Blue LED promotes the chemosensitivity of human hepatoma to Sorafenib by inducing DNA damage

Background:Phototherapies based on sunlight,infrared,ultraviolet,visible,and laser-based treatments present advantages like high curative effects,small invasion,and negligible adverse reactions in cancer treatment.We aimed to explore the potential therapeutic effects of blue light emitting diode(LED)in human hepatoma cells and decipher the underlying cellular and molecular mechanisms.Methods:Wound healing and transwell assays were employed to probe the inhibition of the invasion and migration of hepatocellular carcinoma cells in the presence of blue LED.The sphere-forming test was used to evaluate the effect of LED blue light irradiation on cancer stem cell properties.Immunofluorescence and western blotting were used to detect the changes inγ-H2AX.The Cell Counting Kit-8 assay,5-ethynyl-2′-deoxyuridine staining,and colony formation assay were used to detect the combined effect of blue LED and sorafenib on cell proliferation inhibition.Results:We demonstrated that the irradiation of blue LED light in hepatoma cells could lead to cell proliferation reduction along with the increase of cell apoptosis.Simultaneously,blue LED irradiation also markedly suppressed the migration and invasion ability of human hepatoma cells.Sphere formation analysis further revealed the decreased cancer stemness of hepatoma cells upon blue LED irradiation.Mechanistically,blue LED irradiation significantly promoted the expression of the phosphorylation of the core histone protein H2AX(γ-H2AX),a sensitive molecular marker of DNA damage.In addition,we found that the combined treatment of blue LED irradiation and sorafenib increased cancer cell sensitivity to sorafenib.Conclusion:Collectively,we demonstrated that blue LED irradiation exhibited anti-tumor effects on liver cancer cells by inducing DNA damage and could enhance chemosensitivity of cancer cells,which represents a potential approach for human hepatoma treatment.

Exosomes secreted from cardiomyocytes suppress the sensitivity of tumor ferroptosis in ischemic heart failure

Heart failure(HF)patients in general have a higher risk of developing cancer.Several animal studies have indicated that cardiac remodeling and HF remarkably accelerate tumor progression,highlighting a cause-and-effect relationship between these two disease entities.Targeting ferroptosis,a prevailing form of non-apoptotic cell death,has been considered a promising therapeutic strategy for human cancers.Exosomes critically contribute to proximal and distant organ-organ communications and play crucial roles in regulating diseases in a paracrine manner.However,whether exosomes control the sensitivity of cancer to ferroptosis via regulating the cardiomyocyte-tumor cell crosstalk in ischemic HF has not yet been explored.Here,we demonstrate that myocardial infarction(MI)decreased the sensitivity of cancer cells to the canonical ferroptosis activator erastin or imidazole ketone erastin in a mouse model of xenograft tumor.Post-MI plasma exosomes potently blunted the sensitivity of tumor cells to ferroptosis inducers both in vitro in mouse Lewis lung carcinoma cell line LLC and osteosarcoma cell line K7M2 and in vivo with xenograft tumorigenesis model.The expression of miR-22-3p in cardiomyocytes and plasma-exosomes was significantly upregulated in the failing hearts of mice with chronic MI and of HF patients as well.Incubation of tumor cells with the exosomes isolated from post-MI mouse plasma or overexpression of miR-22-3p alone abrogated erastin-induced ferroptotic cell death in vitro.Cardiomyocyte-enriched miR-22-3p was packaged in exosomes and transferred into tumor cells.Inhibition of cardiomyocyte-specific miR-22-3p by AAV9 sponge increased the sensitivity of cancer cells to ferroptosis.ACSL4,a pro-ferroptotic gene,was experimentally established as a target of miR-22-3p in tumor cells.Taken together,our findings uncovered for the first time that MI suppresses erastin-induced ferroptosis through releasing miR-22-3p-enriched exosomes derived from cardiomyocytes.Therefore,targeting exosome-mediated cardiomyocyte/tumor pathological communication may offer a novel approach for the ferroptosis-based antitumor therapy.