C7, or complement component 7, is an essential part of the complement system within innate immunity. It is crucial for the assembly of the membrane attack complex (MAC), which is a key defense mechanism against invading pathogens [1]. The complement system, in which C7 is involved, plays vital roles in host defense and homeostasis [1].

In a study on prostate cancer, C7 was found to be specifically expressed by stromal cells in both mouse and human prostates. Its expression level is inversely correlated with clinical outcomes in prostate cancer. Androgen signaling positively regulates C7 in mouse prostate stromal cells. Increasing C7 expression in allografts suppresses tumor growth in vivo, while C7 haploinsufficiency promotes tumor growth in the transgenic adenocarcinoma of the mouse prostate (TRAMP) model, indicating its tumor-suppressive role [2].

In conclusion, C7 is essential for the formation of the MAC in the complement system, contributing to host defense. In prostate cancer, model-based research using mouse models has shown that C7 can suppress tumor growth, highlighting its potential significance in cancer-related disease areas.

References:

1. Massri, Mariam, Toonen, Erik J M, Sarg, Bettina, Prohászka, Zoltán, Würzner, Reinhard. 2024. Complement C7 and clusterin form a complex in circulation. In Frontiers in immunology, 15, 1330095. doi:10.3389/fimmu.2024.1330095. https://pubmed.ncbi.nlm.nih.gov/38333209/

2. Zhou, Zhicheng, Jia, Deyong, Kwon, Ohjoon, Lee, John K, Xin, Li. 2023. Androgen-regulated stromal complement component 7 (C7) suppresses prostate cancer growth. In Oncogene, 42, 2428-2438. doi:10.1038/s41388-023-02759-7. https://pubmed.ncbi.nlm.nih.gov/37400528/