Researchers from the Chinese Sichuan Academy of Medical Sciences & Sichuan Provincial People’s Hospital in Chengdu and Nanfang Hospital, Southern Medical University, discovered that the protein LIN28B is able to induce colon cancer migration and recurrence. The study is entitled “LIN28B Promotes Colon Cancer Migration and Recurrence” and was published in the journal PLOS ONE.
Colon cancer is a malignant tumor in the inner walls of the large intestine. In the United States, it is considered the third leading cause of cancer in men and the fourth cause in women. It is estimated that the cancer is responsible for 655,000 deaths worldwide. Colon cancers usually develop from polyps and their removal can prevent the disease.
The protein encoded by the gene LIN28B acts as a suppressor of the let-7 microRNAs family, which are small non-coding (not translated) RNA molecules involved in the regulation of gene expression. LIN28B has been associated with tumorigenesis (generation of tumors) and “stemness” (the ability of undifferentiated cells to differentiate into any type of specialized cell) by blocking the maturation of tumor-suppressive let-7 microRNAs.
Since let-7 is considered a potential growth suppressor in human colon cancer cells, researchers analyzed LIN28B expression in colon cancer tissues to determine the possible balance between LIN28B and let-7 expression.
Researchers found that LIN28B was upregulated in surgical resected tissues and cancer cells from colon cancer patients in comparison with normal tissues, and that this overexpression was associated with a decrease in patient survival and an increase in tumor recurrence probability. On the other hand, downregulation of LIN28B was found to inhibit colon cancer cell migration and to sensitize colon cancer cell lines for the cytotoxicity effects of the drug oxaliplatin (an antineoplastic agent used in cancer chemotherapy).
The team concluded that LIN28B plays an important role in colon cancer development by promoting migration and recurrence. It is important to determine and prevent metastasis and recurrence in malignant tumors, as these are the primary causes for the decrease in patient survival. Researchers suggest that since LIN28B overexpression stimulates colon tumorigenesis and reduces patient survival, LIN28B could be used as a potential therapeutic target and also diagnostic tool for colon cancer.