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Journal of Timely Topics in Clinical Immunology | Volume 2
July 26-28, 2018 | Moscow, Russia
Immunology
11
th
Annual Congress on
Adenosine and Adenosine Receptors in the Immunopathogenesis and Treatment of Cancers
Mohammad Hossein Kazemi
Iran University of Medical Sciences, Iran
I
dentification of the precise mechanisms behind the robust
immunosuppression exerted by tumor cells can help us to
design new therapeutic approaches for cancer therapy. The
generation of adenosine is one of themain immunosuppressive
mechanisms by which tumor cells not only inhibit anti-tumor
responses, but also induce suppressive cells such as regulatory
T cells (Treg). Two cell surface expressed molecules including
CD73 and CD39 catalyze the generation of adenosine from
adenosine triphosphate (ATP). The generation of adenosine
can be enhanced under metabolic stress like tumor hypoxic
conditions. Adenosine exerts its immunoregulatory functions
through four identified adenosine receptors (ARs) including
A1, A2A, A2B and A3 which are expressed on various immune
cells. So, blocking the adenosine generating enzymes or ARs
can be considered as an important therapeutic approach
for cancer therapy. It is demonstrated that signalling of A2A
receptor (A2AR) and A2BR in the tumor microenvironment
can lead to induction and expansion of immunosuppressive
cells such as Treg and MDSC. On the other hand, reports
regarding the effect of A1R and A3R signalling in tumor
biology are controversial. It seems that tumor promoting
or tumor limiting effects of these two receptors depend on
the tumor type and tumor condition. Several ARs directed
agonists and antagonists have been developed and used for
treatment of various tumors. We think the use of these agents
as monotherapy or in combination with other conventional
cancer drugs may lead to promising outcome in near future.
e:
Mohammadhossein.kazemi@yahoo.com