Over the years, there has been a marked change in the modalities of cancer
treatment from the use of surgery and radiation therapy as gold standards to the
employment of chemotherapy and combination approaches using a variety of
modalities. Despite the advances, prognosis generally remains poor due to patients who
develop toxicity or become refractory to therapy. The focus of treatment approaches
has largely been on eliminating tumor cells. However, recent studies have shown that
there is cross talk between tumor cells and their immediate environment, collectively
known as the tumor microenvironment (TME).
The TME contributes to certain characteristics of cancer such as hyperproliferation and
angiogenesis. As such, the TME has been recognized as an important contributor to
cancer progression, cellular invasion and metastatic dissemination. In addition, the
TME has been reported to promote adaptive resistance to therapy in a number of
cancers.
Herein, we provide a brief overview of the pathophysiology of aspects of the tumor
microenvironment. We further review emerging treatment modalities that target this
niche and the mechanisms underpinning the efficacy of these therapies.
Keywords: Angiogenesis, Cancer, Chemotherapy, Drug delivery, Endothelial
cells, Extracellular matrix, Targeted therapy, Tumor associated fibroblasts,
Tumor associated macrophages, Tumor microenvironment.
