Resistance to the platinum‑based chemotherapeutic drugs in oral cancer: Focus on the role of p22phox (Review).

Oral cancer, commonly known as oral squamous cell carcinoma (OSCC), is an aggressive malignancy in the oral cavity with a poor prognosis and survival rate, particularly at the advanced stages. Oral cancer represents one of the most widespread cancers worldwide, in which the prevalence is particularly high in South and Southeast Asia. While the incidence and mortality rates continue to increase over the past decades, oral cancer treatment can be challenging and at times ineffective, largely due to drug resistance. To date, platinum-based drugs, such as cisplatin, remain the mainstay of chemotherapy for patients with oral cancer. However, long-term exposure to cisplatin inevitably leads to the development of resistance to the drug, which is still a major issue to overcome in oral cancer treatment. The molecular mechanisms of cisplatin resistance in oral cancer have been extensively studied in recent years and the present review places specific emphasis on a novel mechanism of resistance to the platinum drugs mediated by p22phox, an endoplasmic reticulum membrane protein. In addition to delineating the unique p22phox-dependent cisplatin resistance, the present review compares and contrasts the resistance mechanism to its current counterparts. Finally, with the goal of tackling the problem of chemotherapy resistance in oral cancer, various strategies are presented that may counteract p22phox-dependent cisplatin resistance, which may potentially improve the efficacy of the platinum-based drugs and warrant future clinical validation.