[Thermo-chemotherapy enhances the immunogenicity of oral squamous cell carcinoma cells by inducing the expression of damage-associated molecular patterns].

OBJECTIVE

To investigate whether hyperthermia, chemotherapy and thermo-chemotherapy could trigger the expression of damage-associated molecular patterns (DAMPs).

METHODS

The optimal working concentration of pingyangmycin (PYM) was detected by CCK-8 assay, and temperatures of 39, 42, and 45 ℃ were applied to the oral squamous cell carcinoma CAL27, SCC-15, and Tca8113 cell lines. The effects of different treatments on the apoptosis, calreticulin (CRT) membrane expression and high-mobility group box 1 (HMGB1) secretion of the cells were detected by using Annexin V/propidium iodide (PI), flow cytometry and enzyme-linked immunosorbent assay (ELISA) assay. SPSS 20.0 software was used for statistical analysis.

RESULTS

Both hyperthermia and chemotherapy could increase the membrane expression of CRT and the secretion of HMGB1, and furthermore, thermo-chemotherapy group showed significantly increased in apoptosis, CRT membrane expression rate and HMGB1 secretion compared with chemotherapy group, and the difference was statistically significant (P<0.05).

CONCLUSIONS

Hyperthermia, chemotherapy and thermo-chemotherapy could induce oral squamous cell carcinoma cells succumb to death, and at the same time, they can effectively induce the membrane expression of CRT, and promote the secretion of HMGB1. Moreover, thermo-chemotherapy is significantly better than that of chemotherapy alone in the induction of cell apoptosis and DAMPs expression.