piR-37524 Overexpression in Colorectal Cancer: A Potential Diagnostic Bio-Marker and Therapeutic Target
Jiaxi Li1, Deepak Iyer1, Siming Sui1
1Department of Surgery, School of Clinical Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, 999077, China.
Objectives:
Piwi-associated RNAs are small non-coding RNAs implicated in cancer, yet few have been characterized in colorectal cancer (CRC). This study aimed to identify a CRC-related piRNA and investigate its clinical relevance, biological function, and biomarker potential.
Methods:
Candidates were identified by reanalysis of small-RNA sequencing. piR-37524 was quantified by quantitative real-time polymerase chain reaction (qRT-PCR) in colorectal cancer tissues, matched adjacent non-tumor tissues, colorectal adenomas, liver metastases, and serum samples from patients and healthy controls. Clinicopathological correlations and diagnostic performance were evaluated. Functional assays included 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) proliferation, colony formation, and wound-healing migration in HCT116 and HT29 cells after piR-37524 inhibition. RNA sequencing and Western blotting examined epithelial-mesenchymal transition (EMT) markers and nuclear factor-kappa B (NF-κB) components.
Results:
piR-37524 was significantly overexpressed in CRC compared with adjacent non-tumor tissues and was associated with larger tumor size, poorer differentiation, and distant metastasis. Elevated expression was also observed in colorectal adenomas and liver metastases. Serum piR-37524 levels were increased in patients with adenomas and CRC compared with healthy controls, indicating diagnostic potential. Functional assays demonstrated that piR-37524 inhibition suppressed CRC cell proliferation and migration, accompanied by changes consistent with epithelial-mesenchymal transition regulation. Mechanistic analyses implicated tumor necrosis factor alpha-induced protein 3 (TNFAIP3)-associated NF-κB signaling.
Conclusions:
piR-37524 is an oncogenic piRNA in CRC that promotes progression via the TNFAIP3/NF-κB/EMT axis, serving as a potential pan-stage diagnostic biomarker and therapeutic target.


