Editorial: Complexity of tumor microenvironment: A major culprit in cancer development

Abstract

The tumor microenvironment (TME) is a complex landscape composed of intrinsic and extrinsic elements besides tumor cells including various immune cells, tumor-related stromal cells, and endothelial cells along with extracellular matrix components (1-3). Notably, the ability of tumor cells to invade surrounding tissues or metastasize through blood and lymphatic vessels implicitly involves cooperation with elements of the TME (4-6). In this regard, infiltrating immune cells such as T cells, B cells, macrophages, dendritic cells, monocytes, neutrophils, and mast cells have been associated with cancer development and progression (6-8). Additionally, these cells stimulate the host immune response by releasing cytokines, cytokine receptors, and other factors, which directly or indirectly promote or alternatively inhibit tumor cell proliferation (9, 10). Collectively these processes direct key events such as tumor recurrence, metastasis, and response to the immunotherapy (11, 12), thereby influencing clinical outcomes (13-15). However, the detailed profiles of immune cell infiltration and differentially expressed genes (metabolic, immune-related, or others) in many cancers continue to be elucidated (7,16,17). Several metabolic factors have shown an association with pathogenesis and progression of various cancers (18, 19) such as de novo lipid biosynthesis is a crucial regulator in the prostate cancer (20)(21)(22). An anecdotal observation metabolic health of the individuals may influence the prognosis and treatment of the cancers.Indeed, support for this intriguing hypothesis is gaining momentum, for example, androgen deprivation therapy (ADT) reduces testosterone in the body which inhibits the prostate cancer (23-25). However, studying constituents of the TME can help understand Frontiers in Endocrinology frontiersin.org 01

Editorial: Complexity of tumor microenvironment: A major culprit in cancer development, volume II

“…Notably, complex interactions and material exchanges between the tumor microenvironment and its surroundings support tumor growth and progression ( 4 , 5 ). Thus, a proper understanding of the TME requires a thorough study of its components and interactions ( 5 , 6 ) with such information being essential for defining the underlying mechanisms of cancer development and progressing anti-cancer therapies for routine clinical use ( 7 – 10 ).…”