Stk32a, encoding a serine/threonine kinase, is involved in multiple biological processes. In the developing mouse inner ear, it regulates hair cell planar polarity opposite of EMX2. In this context, Stk32a is negatively regulated by EMX2, and its expression pattern is complementary to that of Emx2 in hair cells on opposite sides of the line of polarity reversal (LPR). It aligns the intrinsic polarity of the bundle with the core planar cell polarity (PCP) proteins in EMX2-negative regions and can reorient bundles when ectopically expressed in neighboring EMX2-positive regions [1].

In non-small cell lung cancer (NSCLC), the microRNA-130a-5p/RUNX2/STK32A network modulates tumor invasive and metastatic potential. miR-130a-5p directly targets RUNX2, which in turn interacts with STK32A to promote its expression. STK32A supports NSCLC cell growth and NF-κB p65 phosphorylation [2]. Tobacco smoking is associated with DNA methylation changes in the STK32A gene, suggesting a potential role in lung cancer development [3]. In gastric cancer, STK32A is a key target gene of hsa_circ_0005927 significantly associated with immune infiltration [4]. In rat hippocampal neurons, Stk32a is among the genes whose expression is changed by short-term Wnt3a treatment, suggesting its involvement in Wnt/β-catenin-mediated biological processes related to neuronal structure and activity [5]. Association analyses in the Chinese population identified a lung cancer susceptibility locus at 5q32 (rs2895680 in PPP2R2B-STK32A-DPYSL3) with evidence of interaction with smoking dose [6]. In lung adenocarcinoma, a 14-gene-based prognostic model including STK32A can predict prognosis [7]. Also, STK32A shows a correlation with the overall survival (OS) status in lung adenocarcinoma patients [8]. In Partridge Shank chickens, STK32A impacts comb growth as shown by protein-protein interaction network analysis [9]. In lung adenocarcinoma, a 13-gene prediction model including STK32A is related to overall survival and reflects the immune status of patients [10].

In conclusion, Stk32a is a multifunctional gene involved in the regulation of hair cell planar polarity in the inner ear and plays important roles in various cancer-related processes such as NSCLC, gastric cancer, and lung adenocarcinoma, as well as in neuronal development and in the regulation of cocks' comb size. Studies using mouse models and other genetic approaches have been crucial in uncovering these functions, providing insights into the underlying biological mechanisms and potential disease-related pathways.