Compounds, compositions, and methods for preventing metastasis of cancer cells

1. A method for increasing the efficacy of a cancer therapy in a subject in need thereof, the method comprising administering to the subject who has cancer the cancer therapy and an effective amount of a protein tyrosine phosphatase inhibitor, wherein administration of the cancer therapy and the protein tyrosine phosphatase inhibitor provides an efficacy of the cancer therapy that is greater than the efficacy of the cancer therapy in absence of the protein tyrosine phosphatase inhibitor, wherein the efficacy of the cancer therapy and the protein tyrosine phosphatase inhibitor is at least about 10% greater than the efficacy of the cancer therapy in absence of the protein tyrosine phosphatase inhibitor, wherein the protein tyrosine phosphatase inhibitor is a compound of the formula:

wherein:

R is a thiazolyl group that is substituted or unsubstituted;

R 1 is alkyl, phenyl, or benzyl, any of which is substituted or unsubstituted, or hydrogen;

R 2 is alkyl or alkoxy, any of which is substituted or unsubstituted; and

R 3 is hydrogen or alkyl which is substituted or unsubstituted,

or a pharmaceutically-acceptable salt thereof.

2. The method of claim 1 , wherein the cancer is glioma.

3. The method of claim 1 , wherein the cancer is renal cell carcinoma.

4. The method of claim 1 , wherein the cancer is melanoma.

5. The method of claim 1 , wherein the cancer is pancreatic cancer.

6. The method of claim 1 , wherein the cancer therapy is taxol.

7. The method of claim 1 , wherein the cancer therapy is IL-2.

8. The method of claim 1 , wherein the cancer therapy is gemcitabine.

9. The method of claim 1 , wherein the cancer therapy is erlotinib.

10. The method of claim 1 , wherein the cancer therapy is doxil.

11. The method of claim 1 , wherein the cancer therapy is irinortecan.

12. The method of claim 1 , wherein the cancer therapy is bevacizumab.

13. The method of claim 1 , wherein the efficacy of the cancer therapy and the protein tyrosine phosphatase inhibitor is about 50% greater than the efficacy of the cancer therapy in absence of the protein tyrosine phosphatase inhibitor.

14. The method of claim 1 , wherein the efficacy of the cancer therapy and the protein tyrosine phosphatase inhibitor is about 80% greater than the efficacy of the cancer therapy in absence of the protein tyrosine phosphatase inhibitor.

15. The method of claim 1 , wherein the compound is:

16. The method of claim 1 , wherein the compound is:

17. The method of claim 1 , wherein the compound is:

18. The method of claim 1 , wherein the compound is: