Use of ubiquitin-proteasome system inhibitors for treatment of tumors associated with neurofibromatosis type-2

1. A method of treating, preventing or ameliorating a tumor or a symptom arising due to a neurofibromatosis type-2 gene mutation in a subject comprising administering to said subject a therapeutically effective amount of bortezomib.

2. The method as claimed in claim 1 , wherein said tumor is a neurofibromatosis type-2/merlin deficient tumor.

3. The method as claimed in claim 2 , wherein the neurofibromatosis type-2 deficient tumor is selected from the group consisting of vestibular schwannomas, unilateral schwannomas, bilateral vestibular schwannomas, spinal cord schwannomas, sporadic schwannomas, peripheral nerve schwannomas, meningioma, mesothelioma, ependymoma, glioma, astrocytoma, and combinations thereof.

4. The method as claimed in claim 1 , further comprising administering a second ubiquitin-proteasome system inhibitor selected from the group consisting of PI-083, MLN 9708, MLN 4924, MLN 519, Carfilzomib, ONX 0912, CEP-1877, NPI-0052, BU-32 (NSC D750499-S), PR-171, IPSI-001, and a natural product with proteasome-inhibitory effects.

5. The method as claimed in claim 4 , wherein the proteasome inhibitor is carfilzomib.

6. The method as claimed in claim 1 , wherein the bortezomib is a pharmaceutically acceptable salt, derivative, polymorph, racemate, stereoisomer, conjugate or complex thereof.

7. The method as claimed in claim 1 , wherein the bortezomib is administered at a dose in a range of about 0.5 mg/m 2 to about 100 mg/m 2 .

8. The method as claimed in claim 1 , wherein the bortezomib is administered in a dose range of about 0.1 mg to about 50 mg per day.

9. The method as claimed in claim 1 , wherein the bortezomib is administered via a delivery route selected from the group consisting of parenteral, intra-tumoral, oral, intravenous, transdermal, subcutaneous and intramuscular.

10. The method as claimed in claim 1 , wherein the method further comprises administering to said subject one or more additional tumor treatments.

11. The method as claimed in claim 10 , wherein the one or more additional treatments are selected from the group consisting of chemotherapeutic agents, radiotherapeutic agents, antibody-based therapeutic agents, steroids, and combinations thereof.

12. A method of enhancing LATS activity in a tumor having compromised activity of neurofibromatosis type-2/merlin comprising administering bortezomib to a subject having the tumor.

13. The method as claimed in claim 12 , wherein the tumor is from a schwannoma selected from the group consisting of: a vestibular schwannoma, a unilateral schwannoma, a bilateral vestibular schwannoma, a spinal cord schwannoma, a sporadic schwannoma, and a peripheral nerve schwannoma.

14. The method as claimed in claim 12 , wherein the bortezomib is administered in an amount sufficient to increase LATS activity by at least 20%, at least 30%, at least 50%, at least 60%, at least 80%, at least 100%, or at least 150% compared to the activity in an untreated cell having compromised activity of neurofibromatosis type-2/merlin.

15. The method of claim 4 , wherein the second ubiquitin-proteasome system inhibitor is a natural product with proteasome-inhibitory effects and said natural product is selected from the group consisting of green tea polyphenol (−)-epigallocatechin-3-gallate (EGCG), curcumin, and soy isoflavone genistein.

16. The method of claim 7 , wherein the bortezomib is administered to patients in a dose range of about 0.5 mg/m 2 to about 1.3 mg/m 2 .

17. The method of claim 8 , wherein the bortezomib is administered to patients in a dose range of about 1 mg to about 10 mg per day.

18. The method of claim 9 , wherein the administration is subcutaneous or intratumoral.

19. The method of claim 18 , wherein the administration is subcutaneous.

20. The method of claim 10 wherein the additional treatment is a conventional chemotherapeutic agent.

21. The method of claim 20 , wherein the chemotherapeutic agent is selected from the group consisting of alkylating agents, anti-metabolites, plant alkaloids, plant terpenoids, topoisomerase inhibitors, antineoplastics, and combinations thereof.

22. The method of claim 10 wherein the additional treatment is an antibody-based therapeutic agent.

23. The method of claim 22 , wherein the antibody-based therapeutic agent is selected from the group consisting of gemtuzumab, alemtuzumab, rituximab, trastuzumab, nimotuzumab, cetuximab, and bevacizumab.

24. The method of claim 10 wherein the additional treatment is a steroid.

25. The method of claim 24 , wherein the steroid is dexamethasone.