**5. Conclusions**

Considering the possible mechanisms of action of GK-1 and the information available, we propose that this peptide can decrease tumor growth and metastasis by changing the tumor microenvironment. GK-1 appears to reactivate the immune system affected by the tumor-associated suppressive microenvironment, thereby allowing immune cells to become activated. Although more studies focusing on the anticancer effect of GK-1 are required, this research gives new evidence on the possible clinical uses of GK-1 beyond its well-established adjuvant effect.

These results have also provided us with the rationale to evaluate the effectiveness of the GK-1 immunotherapy to revert the exhaustion of peripheral T-cells in several types of cancer.
