In recent years, there is an increasing attention on the impact of tumor microenvironment on tumor initiation, progression and metastasis. Within the tumor microenvironment, malignant tumor cells and nonmalignant stromal cells actively interact with each other and thereby make the microenvironment supportive for the tumor growth. The tumor microenvironment is composed of extracellular matrix and several cell types such as cancer-associated fibroblasts, endothelial cells, tumor-associated macrophages and other immune cells. The literature has been continuously highlighting new aspects on the complexity of these cell types and their pro- and anti-tumoral role in different tumor types.

At the same time, many new cellular and extracellular targets in tumor microenvironment such as new receptors, extracellular proteins and microRNA have been revealed. Modulation of these targets may lead to development of new diagnostics and therapeutics for cancer. To reinforce these developments, it is crucial to involve targeting technologies such as drug and gene targeting technologies to the tumor microenvironment. These technologies are related to delivery of therapeutic molecules to the tumor microenvironment to act as therapeutics or to enhance the therapeutic efficacy of other anti-cancer agents.

This research topic will highlight the novel targets in the tumor microenvironment, which have potential therapeutic implications. In addition, a current update of the new technologies will be presented which can make a huge impact on the modulation of tumor microenvironment by combining the knowledge of tumor biology.

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