The molecular mechanisms involved in the development and progression of
colorectal cancer (CRC) are not completely understood. The present study aimed to identify potential novel genes involved in the development and progression of CRC. Database analysis revealed that the
mRNA level of the
chloride channel accessory 4 (CLCA4) was frequently lower in primary
tumor tissues compared with that in corresponding non-cancerous colon tissues, and was even lower in liver
metastases than in primary
tumors. Further analyses through The Human
Protein Atlas (THPA) website and immunohistochemistry (IHC)-based tissue microarray (TMA) confirmed that CLCA4
mRNA and
protein expression were downregulated in CRC tissues. Furthermore, IHC-based TMA analysis revealed a gradual decrease in CLCA4
protein expression among colorectal normal,
adenoma and
carcinoma tissues. Survival analysis revealed that the decrease in CLCA4
mRNA expression was associated with the overall survival rate of patients with different types of
tumor, including CRC,
breast cancer,
head and neck cancer and
stomach cancer. Overall, downregulated CLCA4 expression may influence the development and progression of CRC.