Relationship between deletion and point mutations of p53 and drug resistance to aranoza in human melanoma cell lines

Abstract

Aranosa, nitrozourea derivative is a DNA-methylating agent that has been approved for treatment of patients with disseminated melanoma. Aranoza effect is based on DNA damage and then as a result apoptosis mechanisms start launching. The important role in this process must be played by p53 protein, and its different dysfunctions can result in drug resistance. Objective. The purpose is to study p53 mutational status in cell lines of human skin metastatic melanoma and to estimate its connection with сell lines resistance to aranoza. Materials and methods. The research was conducted on 14 cell lines of human skin metastatic melanoma. Aranoza IC50 for cell lines was determined by MTT-test. The 17р chromosome’s condition was estimated by fluorescence in situ hybridization. The presence of point mutations in DNA-binding domain of human p53 was researched by Sanger sequencing. Results. Skin metastatic melanoma cell lines had different sensitivity to aranoza. Almost all cell lines were heterogeneous in the condition of 17 th chromosome. P53 point mutations were found in 2 cell lines. But one part of resistant cell lines almost didn’t have any mutational disorders of p53, another part of resistant lines on the contrary had plenty of p53 mutational disorders. Conclusion. The correlation of resistance and p53 mutations can be established for one part of human skin metastatic melanoma cell lines. But for another part of human skin metastatic melanoma cell lines resistance most likely are driven by other mechanisms.