Chrysin and chrysin-loaded nanocarriers induced immunogenic cell death on B16 melanoma cells.

Induction of immunogenic cell death (ICD) is a promising strategy for cancer immunotherapy. Chrysin, which has potential anticancer effects, faces limitations in clinical applications due to its poor water solubility. This study aimed to formulate chrysin with PEG-poly(α-benzylcarboxylate-ε-caprolactone) (PBCL) nanoparticles (NPs) and assess their anticancer and ICD-inducing potency in melanoma cells, comparing with free chrysin. The co-solvent evaporation method was employed to develop chrysin-loaded NPs. UV spectroscopy, dynamic light scattering, and the dialysis bag method were used to evaluate the encapsulation efficiency (EE), particle size, polydispersity index (PDI), and drug release profile, respectively. The anticancer effects of the drugs were assessed using the MTT and trypan blue exclusion assays. Flow cytometry was employed to evaluate apoptosis and calreticulin (CRT) expression. ELISA and western blotting were used to detect heat shock protein 90 (HSP90), Annexin A1, GRP78 (Glucose-related protein78), and activated protein kinase R-like endoplasmic reticulum kinase (p-PERK). Chrysin-loaded PEG-PBCL NPs (chrysin-PEG-PBCL) showed an EE of 97 ± 1%. Chrysin-PEG-PBCL was 38.18 ± 3.96 nm in size, with a PDI being 0.62 ± 0.23. Chrysin-PEG-PBCL showed an initial burst release, followed by sustained release over 24 h. Chrysin-PEG-PBCL exhibited a significantly stronger anticancer effect in B16 cells. Chrysin-PEG-PBCL was found to be more potent in inducing apoptosis. Both free chrysin and chrysin NPs induced ICD as indicated by an increase in the levels of ICD biomarkers. Interestingly, chrysin NPs were found to be more potent inducers of ICD than the free drug. These findings demonstrate that chrysin and chrysin-PEG-PBCL NPs can induce ICD in B16 cells. PEG-PBCL NPs significantly enhanced the potency of chrysin in inducing ICD compared to its free form.

Synergistic effect of chrysin and radiotherapy against triple-negative breast cancer (TNBC) cell lines

Purpose Triple-negative breast cancer (TNBC) is the most aggressive form of breast cancer, accounting for 20% of cases. Due to the lack of a molecular target, limited options are available for TNBC treatment. Radiation therapy (RT) is a treatment modality for the management of TNBC following surgery; however, it has a detrimental effect on surrounding healthy tissues/cells at a higher rate. Methods We examined the effect of RT in combination with chrysin as a possible radiosensitizing agent in an MDA-MB-231 cell line as a model of a TNBC. The growth inhibitory effects of chrysin were examined using an MTT assay. Flow cytometry was performed to evaluate apoptosis and expression of hypoxia-induced factor-1α (HIF-1α). The protein expression of p-STAT3/STAT3 and Cyclin D1 was examined using western blotting. Real-time PCR determined apoptotic-related genes (Bax, BCL2, p53). Results Treatment of MDA-MB-231 cells with chrysin in combination with RT caused synergistic antitumor effects, with an optimum combination index (CI) of 0.495. Our results indicated that chrysin synergistically potentiated RT-induced apoptosis in MDA-MB-231 compared with monotherapies (chrysin and/or RT alone). Expression of HIF-1α was decreased in the cells exposed to combinational therapy. The apoptotic effect of combinational therapy was correlated with increased Bax (pro-apoptotic gene) and p53 levels along with reduced expression of Bcl-2 (anti-apoptotic gene). Increased apoptosis was associated with reduced expression of Cyclin D1, p-STAT3. Conclusion These findings highlight the potential effect of chrysin as a radiosensitizer, indicating the synergistic anti-cancer effect of chrysin and RT in TNBC. Further investigation is warranted in this regard (AU)

Synergistic effect of chrysin and radiotherapy against triple-negative breast cancer (TNBC) cell lines.

PURPOSE: Triple-negative breast cancer (TNBC) is the most aggressive form of breast cancer, accounting for 20% of cases. Due to the lack of a molecular target, limited options are available for TNBC treatment. Radiation therapy (RT) is a treatment modality for the management of TNBC following surgery; however, it has a detrimental effect on surrounding healthy tissues/cells at a higher rate. METHODS: We examined the effect of RT in combination with chrysin as a possible radiosensitizing agent in an MDA-MB-231 cell line as a model of a TNBC. The growth inhibitory effects of chrysin were examined using an MTT assay. Flow cytometry was performed to evaluate apoptosis and expression of hypoxia-induced factor-1α (HIF-1α). The protein expression of p-STAT3/STAT3 and Cyclin D1 was examined using western blotting. Real-time PCR determined apoptotic-related genes (Bax, BCL2, p53). RESULTS: Treatment of MDA-MB-231 cells with chrysin in combination with RT caused synergistic antitumor effects, with an optimum combination index (CI) of 0.495. Our results indicated that chrysin synergistically potentiated RT-induced apoptosis in MDA-MB-231 compared with monotherapies (chrysin and/or RT alone). Expression of HIF-1α was decreased in the cells exposed to combinational therapy. The apoptotic effect of combinational therapy was correlated with increased Bax (pro-apoptotic gene) and p53 levels along with reduced expression of Bcl-2 (anti-apoptotic gene). Increased apoptosis was associated with reduced expression of Cyclin D1, p-STAT3. CONCLUSION: These findings highlight the potential effect of chrysin as a radiosensitizer, indicating the synergistic anti-cancer effect of chrysin and RT in TNBC. Further investigation is warranted in this regard.