Characterization of the role of cancer associated fibroblast derived IL-32 in esophageal squamous cell carcinoma and the role of TRIM22 in gastric cancer

Abstract

Cancer-associated fibroblasts (CAFs) are localized adjacently to cancer cells at all stages of esophageal squamous cell carcinoma (ESCC) progression, and their functional contributions to this process are emerging. Our previous studies have identified FGFR2 as CAFs specific marker in ESCC. In this study, using microarray analysis, we identified IL-32 was the most differentially expressed cytokine in CAFs in patients with ESCC. Flow cytometric analysis and western blot have revealed markedly increased IL-32 in FGFR2+ CAFs from ESCC tumor specimens, compared with non-tumor epithelial tissues. IL-32 treatment could promote prosurvival effect in tumor cell from upon cisplatin or 5-Fu mediated apoptosis in culture and human ESCC tumor-bearing nude mice. In contrast, knockdown of IL-32 expression in CAFs by shRNA reduce tumor cell viability in reconstituted mouse model upon cisplatin or 5-Fu treatment. Mechanistic study shows that IL-32 treatment significantly downregulated caspase 3/9 and upregulated Bcl-2 expression by ESCC tumor upon Cisplatin or 5-Fu stimulation. In contrast, blockage of type II IFN signaling in CAFs resulted in significantly reduced IL-32 secretion and increased apoptotic cell death of ESCC. Together, these findings have suggested a critical role of CAFs derived IL-32 in prosurvival effect ESCC and thereby exacerbating cancer development, which suggested that IL-32 blockade may serve as potential therapeutic target for ESCC.

Gastric cancer is the third leading cause of cancer death worldwide. Lymph node metastasis is a typical malignant behavior of GC. Despite their clinical importance, the mechanisms of LN metastasis have yet to be completely characterized. In this study, using RNAseq analysis, we identified TRIM22 significantly up-regulated in lymph node, compared with tumor and non-tumor tissue in 8 GC patients. Clinical correlation study demonstrated that overexpression of TRIM22 was positively correlated with the differentiation of GC and metastasis to lymph nodes significantly. Knock down the expression of TRIM22 by shRNA in SGC7901 and NUGC4 could significantly suppress proliferation, foci formation, invasion and migration in vitro and in vivo, while ectopic expression of TRIM22 in GC cell lines SUN216 and MKN28 cells could effectively promote these functions. According to cBioPortal database analysis, the correlated genes with TRIM22 specifically involved in NF-κB signaling pathway. Further experiments showed that TRIM22 could active the NF-κB in dose-dependent manner. Both RING(Really Interesting New Gene) and SPRY(SPla and the RYanodine Receptor) domains are necessary for N-κB activation. BAY 11-7082, which is specifically abrogates NF-κB DNA binding were used for block the the signaling pathway. BAY 11-7082 treated TRIM22 overexpressed cells showed lower foci formation frequencies. Meanwhile, the abilities of migration and invasion of TRIM22 overexpressed cells were also suppressed after treatment with BAY 11-7082. These results demonstrated that TRIM22 regulate GC metasistasis dependent on NF-κB/P65 signaling. These finding suggested that TRIM22 may serve as potential therapeutic marker for GC metastasis.