[Expression of glutathione-S-transferase isoenzymes in larynx cancer]

Carcinoma planoepitheliale of larynx is the most common cancer present in the upper part of the respiratory system. The molecular mechanism of this cancer generation is unknown and there is no a specific marker for its early diagnosis. The properties, physiological function, as well as the results of studies on genetic polymorphism indicate that glutathione-S-transferase (GST) may play an important role in etiology of this cancer. In the present work the studies on expession of GST isoenzymes pi, alfa, mu4, and mu5 in larynx cancer (carcinoma planoepitheliale laryngis) were performed. Specimens of larynx cancer and their corresponding normal adjacent tissues were obtained from patients by surgery. Expression was studied on the level of mRNA using RT-PCR method. The results indicated raised expression of GST pi (the major isoform in larynx) and lowered expression of GSTs mu4 and alfa in cancer as compared with the control tissue. No expression of GST mu5 was observed in tumor and normal larynx tissues. Obtained results indicate various mechanism in regulation of GSTs expression in cancerous and normal larynx tissues. They also indicate a special role of GST pi in larynx carcinogenesis.