Role of receptor for advanced glycation end products in the complication and progression of various types of cancers.

BACKGROUND: Receptor for advanced glycation end-products popularly known as RAGE is a cell surface immunoglobulin class of molecule, binds with multiple ligands and therefore considered as a multi-ligand receptor. Use of RAGE deficient mice (RAGE(-/-)) as well as established mouse models pertaining to inflammation-associated carcinogenesis such as that of chemically induced carcinogenesis and colitis associated cancer provides a direct genetic evidence for a likelihood novel role of RAGE in cancer, with respect to its ability to lead cancer cell proliferation and survival. Besides inflammation, interaction of RAGE with its various ligands enhances oxidative stress both in cancerous and noncancerous cells which further complicates the progression of cancers. SCOPE OF REVIEW: Till date, no single review article has discussed the mechanism of RAGE dependent complication of cancers, particularly the role of RAGE in cancer cell proliferation, angiogenesis, survival and anti-apoptosis needs to be discussed. MAJOR CONCLUSION: RAGE enhances the number of cancer cells by activating the cell cycle proteins (e.g., cyclin D1), anti-apoptotic proteins (e.g., BCl2), prosurvival (AKT) and autophagic proteins. Role of RAGE has also been detected in formation of new blood vessels (angiogenesis) in the cancer cells and activation of myeloid derived suppressor cells (MDSCs). GENERAL SIGNIFICANCE: This review article describes the role of RAGE in the complication of various types of cancers and the possible usefulness of RAGE dependent therapy to confront cancers in a stronger magnitude.

Mechanistic insight of drug resistance with special focus on iron in estrogen receptor positive breast cancer.

Estrogens along with their receptors are required for the normal physiological development of women. However, in altered physiological conditions a high level of estrogens acts either as initiator or progressor of breast cancer. Approximately in 75% of estrogen dependent breast cancer cases estrogen receptors (ERs) are held responsible. Recent studies indicate that estrogens along with iron (Fe) concomitantly involved in the proliferation of ER(+) breast cancer cells. While a number of antiestrogen/anti-ER drugs including selective estrogen receptor modulators (SERMs), aromatase inhibitors (AIs) and selective estrogen receptor down regulators (SERDs) are used to eradicate breast cancer but their action on Fe dependent breast cancer complication is not yet explored. Moreover, many of the ER(+) breast cancer patients receiving anti-estrogen drugs relapsed within a couple of years and become resistant to antiestrogen therapy. Mutation and loss of affinity to the target molecule (ERs), loss or overexpression of ERs, along with activation of growth promoting pathways alternative to estrogen-ER pathways are the major reasons of drug resistance. Combinational therapy may be best alternative to antiestrogen relapsed patients. Some of the widely studied drug combinations are roscovitine (ROSC) and tamoxifen, metformin and tamoxifen, tamoxifen and RAD001. While in all these drug combinations anti-ER compound tamoxifen may be one of the major content, anti-Fe compounds are yet to be used as drug combination. The present review article describes all the currently studied drugs/drug combinations in ER(+) breast cancer cells and future drug possibilities including anti-Fe compounds.