The tumor microenvironment has become a very important and hot topic in cancer research within the past few years. The tumor microenvironment is defined as the normal cells, molecules, and blood vessels that surround and feed a tumor cell. As many scientists have realized, studying the tumor microenvironment has become critical to moving the field forward, since there are many players in a tumor’s localized and surrounding area, which can significantly change cancer cell behavior. There is a dual relationship wherein the tumor can change its microenvironment and the microenvironment can affect how a tumor grows and spreads. Tumor Microenvironment in Cancer Progression and Cancer Therapy aims to shed light on the mechanisms, factors, and mediators that are involved in the cancer cell environment. Recent studies have demonstrated that in addition to promoting tumor progression and protecting tumor cells from the spontaneous immune-mediated rejection and different forms of cancer therapeutics, tumor microenvironment can also be a target and mediator of both standard and newly-emerging forms of cancer therapeutics. Thus, the dual role of the tumor microenvironment is the integral focus of the volume. The volume highlights the bi-directional interactions between tumor cells and non-malignant tumor component during tumor progression and treatment. It also focuses on the three groups of the reactive tumor component: stromal cells, blood vessels and the infiltrating immune cells. These three groups are discussed under the lens of their role in promoting tumor growth, shielding the tumor from rejection and from standard forms of cancer therapies. They are emerging as targets and mediators of standard and new forms of potential therapy.

In the past decade, significant progresses have taken place in the field of cancer immunotherapy. Tumor-targeting immunotherapies are being developed for most human cancers, including melanoma, prostate cancer, glioblastoma, sarcoma, lung carcinoma and hepatocellular carcinoma. The FDA has approved multiple molecular immunotherapeutics, such as Ipilimumab; cellular immunotherapies (e.g. adoptive cell transfer) are being tested in phase II/III clinical trials. Immunotherapetics has evolved into a sophisticated field: Multimodal therapeutic regimens are administrated to induce focused responses, curtail side- effects and improve therapeutic efficacy. The lack of effective clinical assessment tools remains a major challenge. Because of the intricacy of antitumor response, it is essential to scrutinize individual tumor-targeting immune cells and their functions at the finest details – molecules. In this regard, flow cytometry analysis modernized hematology and allows characterization of surface molecular signature on individual cells. More recently, microchip technologies and new variations of cytometry have enormously expanded the spectrum, throughout and multiplexity of single cell analysis. Nowadays, tens of millions of readouts can be generated through the course of a cancer immunotherapy to monitor the abundance, phenotype and a myriad of effector functions of single immune cells. At the same time, big data analytics and data mining methodologies have been adapted to achieve sensible diagnostic interpretations. Such a marriage of technology and analytics opens the door for informative point-of-care assessment of therapeutic efficacy and ensures timely therapeutic decisions. The new generation of personalized clinical diagnostics will revolutionize healthcare in the years to come.

Tumor microenvironment represents an extremely dynamic niche shaped by the interplay of different cell types (e.g. tumor cells, stromal cells), their soluble products (e.g.cytokines, chemokines and growth factors) and varied physico-chemical conditions (e.g low oxygen concentration or hypoxia). Recent studies have identified myelomonocytic cells as key players in regulating the tumor microenvironment and hence, tumor progression in a variety of cancers. In view of these findings, the present book attemps to provide a comprehensive account of the diversity of tumor microenvironment across different cancers and how myelomonocytic cells have taken the center-stage in regulating this niche to direct cancer progression. A better understanding of the myelomonocytic cells and the mechanisms by which they regulate cancer progression will open new vistas in cancer therapeutics.