Combination of IL-24 and cisplatin inhibits cervical cancer growth in a xenograft nude mice model.

IL-24/mda-7 delivery augments the sensitivity of several tumor types to cisplatin but the underlying mechanism(s) are unclear. Here, we used a cervical cancer xenograft model in nude mice to further elucidate the interaction between IL-24 and cisplatin. Nude mice were inoculated subcutaneously in the left axilla with Hela cells and randomly grouped into 5 treatment schedules: PBS (I); pDC316 vector (II); pDC316-hIL-24 (III); cisplatin (IV); and pDC316-hIL-24 combined with cisplatin (V). Groups III, IV and V showed significant reduction at mean tumor weight by 43%, 50% and 72%, respectively, after 4 weeks in comparison to thePBS and vector control groups. Mitotic counts in groups III, IV and V were also significantly reduced and expression of tumor suppressor gene nm23-H1 protein was significantly higher in groups III and V than in the cisplatin (IV), PBS (1), and vector (II) cases. The cisplatin group exhibited significantly greater weight loss than the other four groups. The mean weight loss of the combined group, while significantly more than in the controls and the IL-24 group, was significantly less than that of the cisplatin group. The IL-24 group and the combined therapy group exhibited enhancing effects on the tumor suppressor gene nm23H1expression.