ShcA proteins are the family of adaptor proteins that mediate biological
responses by transducing extracellular signals into intracellular signals. ShcA family
consists of three different alternatively spliced or alternative translational initiated
isoforms known as p66Shc, p52Shc and p46Shc. The p52and p46Shc isoforms are
usually involved in promoting cell growth, mediating their action by activating
mitogen-activated protein kinases (MAPK) and phosphoinositide-3-kinase/Akt
signalling pathways. However, the p66Shc isoform acts as a dual player in cell
development and is involved in stimulating both cell proliferative and apoptotic
pathways. Any deregulation in the expression of ShcA proteins and pathways regulated
by ShcA proteins results in the occurrence of different types of cancerous diseases,
including breast cancer, thyroid cancer, prostate cancer and lung cancer. Aberrations in
the expression of ShcA proteins have been demonstrated to promote key elements of
cancer progression, including cell migration, cell proliferation, metabolic
reprogramming, angiogenesis and tumorigenesis. Based on all these studies, the present
chapter focuses on the structure of ShcA proteins and their role in promoting metastasis
and progression of various cancers. Understanding the role of ShcA proteins may
provide new tools for therapeutic interventions in dreadful cancer disease.
Keywords: Adaptor proteins, Apoptosis, Aging, Cell proliferation, Cell
differentiation, Cell signalling, Cell survival, Metabolism, Modular domains,
Neoplasms, Oxidative stress, Reactive oxygen species, Vascularization.
