Role of IQGAP1 in Carcinogenesis

SIMPLE SUMMARY: IQ motif-containing GTPase-activating protein 1 (IQGAP1) is a signal scaffolding protein that regulates a range of cellular activities by facilitating signal transduction in cells. IQGAP1 is involved in many cancer-related activities, such as proliferation, apoptosis, migration, invasion and metastases. In this article, we review the different pathways regulated by IQGAP1 during cancer development, and the role of IQGAP1 in different types of cancer, including cancers of the head and neck, breast, pancreas, liver, colorectal, stomach, and ovary. We also discuss IQGAP1′s regulation of the immune system, which is of importance to cancer progression. This review highlights the significant roles of IQGAP1 in cancer and provides a rationale for pursuing IQGAP1 as a drug target for developing novel cancer therapies. ABSTRACT: Scaffolding proteins can play important roles in cell signaling transduction. IQ motif-containing GTPase-activating protein 1 (IQGAP1) influences many cellular activities by scaffolding multiple key signaling pathways, including ones involved in carcinogenesis. Two decades of studies provide evidence that IQGAP1 plays an essential role in promoting cancer development. IQGAP1 is overexpressed in many types of cancer, and its overexpression in cancer is associated with lower survival of the cancer patient. Here, we provide a comprehensive review of the literature regarding the oncogenic roles of IQGAP1. We start by describing the major cancer-related signaling pathways scaffolded by IQGAP1 and their associated cellular activities. We then describe clinical and molecular evidence for the contribution of IQGAP1 in different types of cancers. In the end, we review recent evidence implicating IQGAP1 in tumor-related immune responses. Given the critical role of IQGAP1 in carcinoma development, anti-tumor therapies targeting IQGAP1 or its associated signaling pathways could be beneficial for patients with many types of cancer.