Chemotherapeutics-induced Oct4 expression contributes to drug resistance and tumor recurrence in bladder cancer

Area of Science:

• Oncology
• Molecular Biology
• Cancer Stem Cell Research

Background:

• Acquired chemotherapy resistance is a major challenge in treating recurrent bladder cancer.
• The role of Oct4 in chemotherapy-induced drug resistance and tumor recurrence in bladder cancer requires further investigation.

Purpose of the Study:

• To investigate if anticancer drugs induce Oct4 expression, contributing to acquired drug resistance and tumor recurrence in bladder cancer.
• To explore the therapeutic potential of inhibiting Oct4 in overcoming cisplatin resistance.

Main Methods:

• Correlation analysis of Oct4 expression with tumor recurrence in 122 bladder cancer specimens.
• Assessment of Oct4 induction by chemotherapy (cisplatin) in bladder cancer cells.
• In vitro and in vivo experiments evaluating the effect of Oct4 modulation (forced expression and knockdown) on drug sensitivity.
• Combination therapy studies using cisplatin and all-trans retinoic acid (ATRA).

Main Results:

• A positive correlation was found between Oct4 expression and tumor recurrence in bladder cancer patients, with higher Oct4 levels associated with shorter recurrence-free intervals.
• Chemotherapy, specifically cisplatin, induced Oct4 expression and increased CD44-positive cancer stem-like cells.
• Overexpression of Oct4 reduced, while knockdown enhanced, drug sensitivity in bladder cancer cells.
• Inhibition of Oct4 by ATRA synergistically increased cisplatin sensitivity, and the combination therapy suppressed tumor growth more effectively than cisplatin alone.

Conclusions:

• Oct4 plays a crucial role in promoting acquired drug resistance and tumor recurrence in bladder cancer.
• Inhibiting Oct4, for example, with ATRA, represents a promising therapeutic strategy to overcome chemotherapy resistance and improve treatment outcomes in bladder cancer.