miR-135b: A key role in cancer biology and therapeutic targets.

miR-135b, a microRNA, is consistently up-regulated in various cancer tissues and cells, promoting cancer progression. By inhibiting one or more target genes, miR-135b regulates phenotypes such as cancer growth, apoptosis, migration, invasion, drug resistance, and angiogenesis, establishing it as a critical driver of cancer progression. Additionally, miR-135b is regulated by various oncogenes and therapeutic drugs, highlighting its complexity and therapeutic potential. Significant progress has been made in understanding miR-135b's impact on cancer cell behavior, establishing it as a promising biomarker for cancer diagnosis and prognosis, as well as a potential target for future cancer therapies. However, despite the extensive research on this topic, there has been no comprehensive review summarizing its role and mechanisms across different cancer types. This review aims to provide a detailed overview of the biological characteristics of miR-135b, its regulatory targets, upstream signaling pathways, and its therapeutic potential, including its influence on cancer chemoresistance. The review also addresses key controversies surrounding miR-135b in cancer research, aiming to deepen the understanding of its role, promote the transformation of its clinical application, and provide a theoretical foundation for developing more effective cancer treatment strategies.