| Mast cells (MCs), a type of innate immune cells, are derived from myeloid stem cells, sometimes known as
mastocytes or labrocytes, and contain many granules rich in histamine and heparin. The mentioned cells are able
to release various mediators such as cytokines, leukotrienes, and a large number of proteases into the environment.
Many studies and experiments have established the infiltration of MCs into the tumor site. However,
the findings are highly controversial to determine whether these immune cells contribute to the growth and
development of the tumor or cause anti-tumor immune responses. Various studies have revealed that MCs have a
pro-tumorigenic or anti-tumorigenic role depending on the type of cancer, the degree of tumor progression, and
the location of these immune cells in the tumor bulk. Although these types of immune cells cause angiogenesis
and tumor progression in some cancers, they have a significant anti-tumor role in some other types of cancers. In
general, although a number of studies have specified the protective role of MCs in cancers, the increased number
of MCs in the blood and microenvironment of tumors, as well as the increased level of angiogenesis and tumor
progression, has been indicated in another array of studies. The function of MCs against or in favor of the cancers
still requires further investigations to more accurately and specifically determine the role of MCs in the cancers.
The function of MCs in tumors and their various roles in case of exposure to the cancer cells have been addressed
in the present review. The concluding section of the present study recommends a number of methods for
modification of MCs in cancer immunotherapy. |