Aim of the study. To assess the role of genes RAD50 and SMARCA5 in regulation of sensitivity to cisplatin and other anticancer DNA damaging drugs (5-fluorouracil, olaparib), to assess the role of these genes in the response to the DNA damage in ovarian cancer (OVCAR-8) and head and neck cancer cell lines (SCC61, SCC25). Material and Methods. We used small interfering RNAs (siRNAs) (Qiagen,Germany) to deplete either RAD50 and SMARCA5 or control genes and under basal and DNA damaging drug-treatment conditions, we assessed cell viability with the use of Cell Titer Blue reagent (Promega,USA) with following spectrophotometry. To assess the role of genes in response to DNA damage, analysis of phospho-H2AX focus formation was performed by means of using immunofluorescence microscopy. Results. We demonstrated the role of RAD50 and SMARCA5 in regulation of survival and sensitivity of ovarian cancer (OVCAR-8), head and neck cancer cell lines (SCC61, SCC25) to cisplatin and other DNA damaging drugs (5-fluorouracil, olaparib). Our data suggest the role of SMARCA5 in regulation of baseline histone H2AX protein phosphorylation in the absence of DNA damage. Conclusion. Our findings characterize genes RAD50 and SMARCA5 as promising therapeutic targets and predictive markers for response to cisplatin and other DNA damaging drugs in patients with ovarian cancer and squamous cell carcinoma of head and neck.
EGFR overexpression increases radiotherapy response in HPV-positive head and neck cancer through inhibition of DNA damage repair and HPV E6 downregulation
