MicroRNA Dysregulations in Gastrointestinal Cancers: Pathophysiological and Clinical Perspectives

cancer and the intestinal type of gastric cancer usually follows stepwise progression with recognizable pre-neoplastic changes (i.e., adenoma and intestinal metaplasia for colorectal and gastric cancers, respectively). Therefore, screening and early diagnosis remain the preferred options to ease the disease burden. Surgical resection is the mainstay treatment for gastrointestinal cancers. Other treatment modalities, such as chemotherapy, radiation therapy and novel targeted therapy, have also been devised for the management of gastrointestinal cancers. Nevertheless, the prognosis for advanced stage patients with metastatic lesions is still very poor. Therefore, a more comprehensive and in-depth understanding of the molecular pathogenesis of gastrointestinal cancers and thus the development of next-generation targeted cancer therapeutics are needed. Despite the complex interactions among different etiological factors, the pathogenesis of cancer converges on the dysregulation of intracellular signals. Important dysregulated signaling pathways in gastrointestinal cancers include the epidermal growth factor receptor (EGFR)/Ras/Raf/mitogen-activated MicroRNA Dysregulations in Gastrointestinal Cancers: Pathophysiological and Clinical Perspectives