Tumor associated macrophages in the molecular pathogenesis of ovarian cancer

The tumor microenvironment is a critical factor that enhances cancer progression, drug resistance, and failure of therapeutic approaches. Several cellular and non-cellular factors are involved in cancer promotion. Among the several cell populations in the tumor microenvironment, macrophages, as one of the most abundant innate immune cells within the tumor milieu, have attracted extensive attention among several researchers because of their critical role in innate pathophysiology of multiple disorders, as well as ovarian cancer. High plasticity and consequent high ability to adapt to environmental alternations by adjusting their cellular metabolism and immunological phenotype is the notable characteristic of macrophages. Therefore, the critical function of tumor-associated macrophages in ovarian cancer is highlighted in the growing body of recent studies. In this article, we will comprehensively focus on significant impacts of the macrophages on ovarian cancer progression, by discussing the role of macrophages as one of the fundamental immune cells present in tumor milieu, in metabolic reprogramming of transformed cells, and involvement of these cells in the ovarian cancer initiation, progression, invasion, and angiogenesis. Moreover, we will summarise recent studies evaluating the effects of targeting macrophages in ovarian cancer.