GPRIN1, short for G protein-regulated inducer of neurite outgrowth 1, is involved in multiple biological processes. It is associated with the regulation of axon growth in hippocampal neurons, where it targets the α7 nicotinic receptor to the growth cone and is linked to a Gαo, growth-associated protein 43, and CDC42 cytoskeletal regulatory pathway [2]. It also participates in the serotonin signaling pathway as 5-HT6 receptors can associate with GPRIN1, playing a key role in dendritic tree morphogenesis [1].

Research on GPRIN1 has implications in cancer. In lung adenocarcinoma and kidney renal papillary cell carcinoma, GPRIN1 is up-expressed and correlated with poor prognosis. A pan-cancer analysis suggested that LINC00894/MMP25-AS1/SNHG1/LINC02298/MIR193BHG-miR-140-3p might be the upstream regulation pathway of GPRIN1, and its expression is significantly correlated with tumor immune cell infiltration, immune cell biomarkers, and immune checkpoints [3]. In lung cancer, GPRIN1 facilitates proliferation and migration, possibly by affecting epithelial-mesenchymal transition, and is an independent predictive factor for lung adenocarcinoma prognosis [5]. In breast cancer, high expression of GPRIN1 predicts poor prognosis, and it is involved in the development of breast cancer through immune aspects [4].

In conclusion, GPRIN1 plays essential roles in neural development, regulating axon growth and dendritic tree morphogenesis. In the context of cancer, it is associated with poor prognosis in multiple cancer types, including lung, kidney, and breast cancers, and is involved in processes such as tumor cell proliferation, migration, and immune-related tumor development. These findings from in vivo-like studies (although no KO/CKO mouse models were specifically mentioned in the references) highlight its importance as a potential biomarker and therapeutic target in cancer.

References:

1. Bockaert, Joël, Bécamel, Carine, Chaumont-Dubel, Séverine, Vandermoere, Franck, Marin, Philippe. 2021. Novel and atypical pathways for serotonin signaling. In Faculty reviews, 10, 52. doi:10.12703/r/10-52. https://pubmed.ncbi.nlm.nih.gov/34195691/

2. Nordman, Jacob C, Phillips, Wiktor S, Kodama, Nathan, Del Negro, Christopher A, Kabbani, Nadine. 2014. Axon targeting of the alpha 7 nicotinic receptor in developing hippocampal neurons by Gprin1 regulates growth. In Journal of neurochemistry, 129, 649-62. doi:10.1111/jnc.12641. https://pubmed.ncbi.nlm.nih.gov/24350810/

3. Zhou, Qiwei, Li, Diangeng, Zheng, Hongying, Bao, Peng Tao, Jin, Meiling. 2021. A novel lncRNA-miRNA-mRNA competing endogenous RNA regulatory network in lung adenocarcinoma and kidney renal papillary cell carcinoma. In Thoracic cancer, 12, 2526-2536. doi:10.1111/1759-7714.14129. https://pubmed.ncbi.nlm.nih.gov/34453499/

4. Jiang, Fa, Yang, Lifeng, Jiao, Xiong. 2023. Dynamic network biomarker to determine the critical point of breast cancer stage progression. In Breast cancer (Tokyo, Japan), 30, 453-465. doi:10.1007/s12282-023-01438-5. https://pubmed.ncbi.nlm.nih.gov/36807044/

5. Zhuang, M Q, Li, J, Han, X, Hao, G J, Han, J Q. . G protein regulated inducer of neurite outgrowth 1 is a potential marker for lung cancer prognosis. In Journal of biological regulators and homeostatic agents, 34, 853-864. doi:10.23812/20-136-A-39. https://pubmed.ncbi.nlm.nih.gov/32755106/