CCNB1 and esophageal cancer: No significant changes in the expression of cyclin B1, cyclin D1 or cleaved PARP were detected in RBM22-downregulated OE33 cells, suggesting that in esophageal cancer cells, the cancer cell growth was regulated by another mechanism that was not mediating the expressional changes in cyclin B1, cyclin D1 or cleaved PARP.