Synj2, short for synaptojanin 2, encodes an inositol polyphosphate phosphatase. It functions in recycling neurotransmitter vesicles and is implicated in spermatogenesis [5]. It is also involved in pathways like protein digestion and absorption, extracellular matrix-receptor interaction, and may play a role in the immune response [1].

In various cancers, SYNJ2 shows significant implications. In lung squamous cell carcinoma (LUSC), it is upregulated at both mRNA and protein levels, and overexpression predicts poor prognosis [1]. In papillary thyroid carcinoma (PTC), it is highly expressed and may promote PTC progression through angiogenesis and epithelial-mesenchymal transition (EMT) pathways [2]. In gastric cancer, it promotes cell metastasis and angiogenesis by up-regulating GRB2 [3]. Also, a variant rs9365723 on SYNJ2 is associated with the risk of colorectal cancer, especially colon cancer [4]. In hepatocellular carcinoma (HCC), upregulated SYNJ2 might accelerate the occurrence and development via metabolic perturbation pathways [6].

In conclusion, Synj2 is crucial for multiple cellular functions and is significantly associated with cancer development and progression. Studies on Synj2 help in understanding the mechanisms of cancer occurrence, potentially providing new strategies for cancer treatment and prevention.