Effects of hyperthermia on the gene expression of heat shock proteins in hMLH1-deficient tumor cells

SOTTILE M.L.; CIOCCA D.R.; VARGAS ROIG L.M.; NADIN S.B.

San Juan

Congreso; 2da Reunión Conjunta de Sociedades de Biología de la República Argentina; 2011

Sociedad de Biología de Cuyo

Exposure of cells to a transient elevation of temperature induces the expression of heat shock proteins (HSPs). Several tumor cell lines constitutively express HSP27 and HSP72, which are critical for cell proliferation and survival, they have been also associated with DNA repair and drug resistance. However, the relation between HSPs and Mismatch Repair (MMR) has not been established. The aim of the study was to analyze the mRNA expression levels of HSP27, HSP72, HSF1, hMLH1 and hMSH2 in colon cancer MMR-proficient (HCT116+ch3) and deficient cell lines (HCT116 and HCT116+ch2). Cells were exposed to a mild hyperthermia (41 and 42°C, 1 hour) and then collected at different times. mRNA levels were determined by RT-qPCR. Constitutive expression of HSP27 and HSP72 was higher in HCT116+ch3 cells. After hyperthermia, mRNA levels of HSP27, HSP72, HSF1, hMLH1 and hMSH2 significantly increased in all cell lines, buy they were higher in  HCT116+ch3 cells. Our results suggest that the MMR system may participate in the heat shock response and HSF1could modulate this activity.