RPL38 (ribosomal protein L38) is a component of the large ribosomal subunit that functions as a structural constituent of the ribosome, participating in cytosolic translation and protein synthesis 1. The protein is ubiquitously expressed across epithelial cell lines and is encoded by a small set of genes without forming a multigene family 1. Beyond its canonical ribosomal function, RPL38 has emerged as an important regulator in disease contexts. RPL38 expression is significantly upregulated in hepatocellular carcinoma, where it regulates HOXA9 expression to promote cell proliferation, metastasis, and prevent apoptosis 2. Similarly, in gastric cancer, RPL38 is highly expressed and represents an independent risk factor for poor prognosis, correlating with immune infiltration patterns 3. RPL38 is predominantly expressed in pancreatic ductal epithelium and is upregulated in pancreatic cancer cell lines, suggesting potential utility as a tumor marker 4. In clear cell renal cell carcinoma, RPL38 functions as a core ribosome biogenesis-related gene driving tumor progression through metabolic reprogramming and immune evasion 5. Additionally, RPL38 serves as a diagnostic biomarker for acute kidney transplant rejection when combined with mitophagy-related genes 6. FAM99B suppresses HCC progression by inhibiting RPL38 transcription and ribosome biogenesis 7. These findings establish RPL38 as both a fundamental ribosomal protein and a clinically relevant oncogenic driver across multiple cancer types.