Clinical, Prognostic and Therapeutic Significance of Heat Shock Proteins in Cancer

Background: Heat Shock Proteins (HSPs) constitute a group of proteins that play a crucial role in the process of protein folding. HSPs are also known to modulate a number of key apoptotic factors. High expression of these proteins is reported in an array of cancers, such as breast, prostate, colorectal, lung, ovarian, gastric, oral and esophageal cancer. Ample amount of investigations were carried out on a variety of cancers suggesting HSPs as a promising hallmark in cancers. Their expression profile in several tumors elucidates that they help in proliferation, invasion, metastasis and death of cancerous cells. Detection of the levels of heat shock proteins and their specific antibodies in the sera of diseased individuals can play an important role in cancer diagnosis. Objectives: This review will present and summarize latest research being carried out on heat shock proteins. It will also highlight the clinical and prognostic features of HSP27, HSP60, HSP70, HSP90 and HSP110, and will discuss future implications of HSPs in the diagnosis and prognosis of cancer. Furthermore, the role of heat shock proteins as a therapeutic target in cancer will be discussed. In addition, the review article will report various studies, where HSPs have been targeted for their therapeutic potential. Conclusion: In summary, multiple experimental investigations have been successful in suggesting the role of heat shock protein as a clinical biomarker and therapeutic target in cancer. HSPs are associated with a number of cancer hallmarks such as cell proliferation, invasion and metastasis. Inhibition of HSPs has resulted in successful therapeutic outcome in cancer. It has served as a novel anti- cancer therapy for the treatment of several cancer forms. However, more experimental studies are required to elucidate the reliability and efficacy of heat shock proteins in combination with other conventional markers for cancer diagnosis and prognosis. Novel and effective interventions through HSP inhibition are expected to decrease the burden of cancer in the near future.