Method for treating and prognosing cancer

1. A method of treating cancer in a subject in need thereof, wherein the method comprises:

i) determining the interaction level between DNMT3A/ISGF3gamma proteins in a sample from said patient,

ii) comparing said interaction level with a predetermined reference value, wherein the predetermined reference value is the interaction level of the DNMT3A/ISGF3gamma proteins in a healthy subject or a mean interaction level of the DNMT3A/ISGF3gamma proteins in a population of healthy individuals, and

iii) if the interaction level of the DNMT3A/ISGF3gamma proteins from the patient is higher than the predetermined reference value, administering a therapeutically effective amount of a compound which is a DNMT3A/ISGF3gamma antagonist reducing the interaction between DNMT3A and ISGF3gamma proteins, wherein said DNMT3A/ISGF3γ antagonist is peptide comprising an amino acid sequence RPMPRLTFQAGDPYYI (SEQ ID NO:1) or a function-conservative variant thereof, wherein said function-conservative variant comprises the amino acid sequence RPMPRLTFQAGDPYYI (SEQ ID NO:1) with 1, 2, 3, 4, or 5 amino acids that differ from RPMPRLTFQAGDPYYI (SEQ ID NO:1), and wherein said peptide or function-conservative variant thereof is of less than 50 amino acids.

2. The method according to claim 1 , wherein the method further comprises administering to the subject a chemotherapeutic agent and/or a radiotherapy.

3. The method according to claim 2 , wherein the compound which is a DNMT3A/ISGF3gamma antagonist is administered simultaneously, separately or sequentially with the chemotherapeutic agent and/or the radiotherapy.

4. The method according to claim 2 , wherein the chemotherapeutic agent is temozolomide, and wherein temozolomide and radiotherapy are administered simultaneously, separately or sequentially with the peptide or function-conservative variant thereof.

5. The method according to claim 1 , wherein the method further comprises administering to the subject temozolomide and radiotherapy.

6. The method according to claim 1 , wherein the determination of the interaction level of the couple DNMT3A/ISGF3gamma is determined before or after the beginning of the treatment of the patient.

7. The method according to claim 1 , wherein the subject suffering from cancer already received a conventional treatment, wherein the conventional treatment is selected from chemotherapy and/or radiotherapy.

8. The method according to claim 1 , wherein the cancer is selected from the group consisting of bile duct cancer, bladder cancer, bone cancer, brain and central nervous system cancer, breast cancer, Castleman disease, cervical cancer, colorectal cancer, endometrial cancer, oesophagus cancer, gallbladder cancer, gastrointestinal carcinoid tumors, Hodgkin's disease, non-Hodgkin's lymphoma, Kaposi's sarcoma, kidney cancer, laryngeal and hypopharyngeal cancer, liver cancer, lung cancer, mesothelioma, plasmacytoma, nasal cavity and paranasal sinus cancer, nasopharyngeal cancer, neuroblastoma, oral cavity and oropharyngeal cancer, ovarian cancer, pancreatic cancer, penile cancer, pituitary cancer, prostate cancer, retinoblastoma, rhabdomyosarcoma, salivary gland cancer, skin cancer, stomach cancer, testicular cancer, thymus cancer, thyroid cancer, vaginal cancer, vulvar cancer, and uterine cancer.

9. The method according to claim 1 , wherein the cancer is glioblastoma.

10. The method according to claim 9 , wherein the subject suffering from cancer has already been treated with maximal surgical resection, radiotherapy, and concomitant adjuvant chemotherapy with temozolomide.

11. The method according to claim 1 , wherein the interaction level between DNMT3A/ISGF3gamma proteins in the sample is determined by Proximity Ligation In Situ Assays (p-LISA) or by bioluminescence resonance energy transfer (BRET).