Interestingly, TAp73 and KAI1 are overexpressed in primary colorectal cancers and a significant correlation between TAp73 and KAI1 expression was detected, but their expressions were significantly down-regulated in metastatic cancers.
Furthermore, expression of two genes from the signature, CD82 and S100A4, correlated with stromal VDR expression and clinical outcome in our cohort of patients with CRC.
KAI1 COOH-terminal interacting tetraspanin (KITENIN) contributes to tumor progression and poor clinical outcomes in various cancers including colorectal cancer.
We undertook a case-control study to analyze two KAI1/CD82 polymorphisms (exon 3 -29166 C>T and exon 9 -52840 C>A) in an Han Chinese population, by extraction of genomic DNA from the peripheral blood of 356 patients with CRC and 378 control participants, and performed KAI1/CD82 genotyping using DNA sequencing.
KAI1 expression was detected by in situ hybridization and immunohistochemistry in the 4 established cell lines of colorectal carcinoma with different metastatic potentials, and in 80 specimens of colonic carcinoma, 21 colonic carcinoma specimens with lymphatic metastasis and 20 controls of normal colonic mucosa.
These data indicate a complex relationship between KAI1 and progression of human CRC, in which expression is reduced in localised primary tumours, but regained in disease associated with metastasis.
KAI1 mRNA and protein expression was examined in 36 primary colorectal carcinomas and 6 liver metastasis using Northern blot and Western blot analyses.