[Preliminary research on the effect of antisense oligodeoxynucleotides of tankyrase 1 on tumor growth following intratumoral injection in mice].

Objective: To observe the suppressing effect of antisense oligodeoxynucleotides of tankyrase 1 (TANK1-ASODN) on murine tumor growth following intratumoral injection, and to explore its potential use in clinical treatment of lung cancer.

Methods: After human lung cancer cells CALU had been inoculated subcutaneously to BALB/c nude mice and grew to tumor nodules, these mice were distributed randomly into three groups: four in the saline group, five in the TANK1-ASODN group, and another five in the sense oligodeoxynucleotides of tankyrase (TANK1-SODN) group. Multiple direct intratumoral injections of TANK1-ASODN, TANK1-SODN or saline were given into the tumor nodules, respectively. The tumor growth and the histopathological characteristics were observed and the expression of ki67 and telomerase hTERT in tumor cells were measured by SABC immunohistrochemical method.

Results: After 16 days of continuous injection, the tumor volume of the TANK1-ASODN group was significantly smaller than that of the TANK1-SODN (P < 0.01) and saline-treated groups (P < 0.01); tumor cell degeneration and necrosis were observed in mice treated with TANK1-ASODN. Moreover, a statistically significant decrease in Ki67 labeling index (P < 0.01) and the positive expression ratio of telomerase hTERT (P < 0.01) was observed in the TANK1-ASODN group.

Conclusions: Human lung tumor cell lines express high telomerase activity. TANK1-ASODN can inhibit the activity of telomerase and suppress the proliferation of tumor cells.