Malignant tumors that are intrinsically resistant to conventional therapies are significant therapeutic challenges. An embodiment of the present invention provides an oncolytic virus capable of killing target cells, such as a tumor cells. In various embodiments presented herein, the oncolytic virus is armed or encodes a therapeutic polypeptide. In at least one embodiment, a recombinant oncolytic virus has been generated that can specifically replicate in cancer cells leading to their destruction and at the same time secrete robust amounts of a therapeutic polypeptide. Compositions and methods disclosed herein have broad therapeutic applicability.
