MIR99AHG: a novel lncRNA host gene with diverse regulatory roles in cancer

Abstract MIR99AHG, a recently discovered long non-coding RNA (lncRNA), serves as the host gene for the miR-99a/let-7c/miR-125b-2 miRNA cluster. The intricate processing of its three introns yields three distinct micro RNAs (miRNAs). Experimental evidence highlights significant variations in MIR99AHG expression across various cancer types, indicating its potential as a diagnostic marker for cancer. Moreover, FOXA1 acts as an upstream regulator, actively promoting MIR99AHG expression. MIR99AHG, in turn, regulates five downstream proteins (ANXA2, PTBP1, MMP9, PBX3, and PHB2), as well as three competing endogenous RNA (ceRNA) axes and three signaling pathways. This broad spectrum of regulatory effects underscores the pivotal role of MIR99AHG in shaping the behavior of cancer cells. In cancer treatment, MIR99AHG's functions are equally noteworthy. Experimental findings suggest its impact on immune cell activity within the tumor micro-environment and its role in modulating cancer cell resistance to chemotherapeutic drugs. Follow-up studies on patients further confirm the close association between high MIR99AHG expression and poor prognosis across various cancers, exhibiting significant statistical correlations with various pathological behaviors. In summary, MIR99AHG, acting as a multifaceted lncRNA, not only introduces a potential novel marker for cancer diagnosis but also demonstrates significant application value in cancer treatment and prognosis evaluation.