How Signaling Pathways Activate Cancer Cells
Cancer has become an epidemic as it accounts for every sixth death in the world. According to a World Health Organization (WHO) data, 9.6 million people had died from cancer worldwide in 2018.
Cancer is a collection of diseases characterized by the growth of abnormal cells beyond their usual boundaries that can affect adjacent parts of the body or spread to other organs. These abnormal cells disrupt normal cell functions and cause cancer cells to proliferate and avoid mechanisms that control their growth, division, and migration. Cancer cells disrupt normal cell functioning that can be mapped to specific cell signaling pathways.
Cell signaling controls basic cellular activities via complex responses which helps them to respond and adapt to their environment by processing information that originates outside the cells. It enables a cell to sense if their state of attachment to the extracellular matrix and other cells is appropriate. Abnormal cell signaling of one pathway can disrupt other signaling networks, which results in cancer progression and metastasis. Here are a few examples of signaling pathways that are abnormally activated in cancer:
Ras Proteins: The functionality of Ras proteins is to control the activation and regulation of pathways that are responsible for numerous cell behaviors like survival, proliferation, migration and so on. The Ras protein signaling cascade can be activated by several different stimuli like receptor tyrosine kinase and G protein-coupled receptors.
Wnt/β-catenin signaling: Aberrant Wnt signaling causes numerous cancers like leukemia, melanoma, breast and gastrointestinal cancers. According to a report by The cancer genome Atlas (TCGA) consortium, it is estimated that more than ninety percent of sporadic colorectal cancers contained alterations in a Wnt pathway regulator. Healthcare industry is exploring various Wnt-signaling pathway inhibitors for a range of different cancers including colorectal, melanoma and breast.
NF2 gene: The Neurofibromatosis Type 2 (NF2) gene suppresses tumor and encodes a cytoskeletal protein called moesin-ezrin-radixin-like protein. It helps to regulate various pathways which are responsible for controlling cell shape, growth, and adhesion. The NF2 gene stops cells from dividing in an uncontrolled way by sensing cell-to-cell contact and restricting its increase.