  Oncolytic viruses, which may be naturally occurring or genetically
engineered, are a type of virus that infects and destroy cancer cells
preferentially. Owing to their selectivity, they outperform conventional
chemotherapy and radiotherapy, which both have a tendency to impact non-target
cells and cause unwanted adverse side effects. Oncolytic virotherapy is a type
of cancer treatment in which oncolytic viruses are deliberately introduced into
patients affected with cancers in order for them to infect and destroy cancer
cells locally or systemically, in a manner analogous to chemotherapy but with a
greater degree of selectivity. Multiple studies indicate that oncolytic
virotherapy is effective in vitro but in vivo findings remain ambiguous due to
the approach's primary limitation: inefficient therapeutic agent delivery to
its target, which is heavily influenced by the immune system. Here, we propose
overcoming this limitation by exploiting a recent discovery in cancer research:
a carrier cell. By exploiting their tumor-promoting activities, mesenchymal
stem cells may be employed for cancer therapy by serving as a carrier for the
oncolytic viruses toward their target. This approach directly addresses the
limitation of conventional oncolytic virotherapy, where oncolytic viruses are
often poorly delivered after systemic administration.
