This is non-randomized phase 2 study to evaluate toxicity and efficacy of VA with concurrent chemoradiotherapy (CCRT) containing weekly vinorelbine and cisplatin in patients with locally advanced inoperable non-small-cell lung cancer (NSCLC).All patients will be planned for three-dimensional conformal RT (3-DCRT). Concurrent weekly vinorelbine and cisplatin and oral valproic acid (VA)will be started at the first day of RT. Follow up will be conducted every 3 months after completion of the study treatment. Toxicity will be assessed using CTCAE, based on clinical examination and laboratory tests during the study treatment and at follow up visits. Response to treatment will be evaluated using RECIST criteria. Overall and progression free survival (OS and PFS) will be estimated using the Kaplan-Meier method.

Inclusion Criteria:

1. Age > 18 years.

2. Newly-diagnosed, histologically or cytologically confirmed NSCLC.

3. Inoperable stage IIIA-B disease

4. KPS > 60

5. FEV1 >1.2L

6. No previous RT to chest

7. No serious comorbid condition

8. No treatment with biological response modifiers or cytotoxic agents within four weeks prior to study entry

9. No participation in clinical trial using any investigational drug or device within four weeks prior to study entry

10. No serious complication of malignant condition

11. No previous or concurrent malignancy at other sites except cone biopsied in situ carcinoma of the uterine cervix and adequately treated basal cell or squamous cell carcinoma of the skin

12. Adequate organ function as evidenced by the following peripheral blood counts or serum chemistries at study entry:

    Hemoglobin > 9.0 Gm/dL WBC count > 4.0x109/L Neutrophile count > 1.5 cells x 109/L, Version 1, May 12, 2010 Platelet count > 100 x 109/L, Creatinine < 1.5 mg/dL Total bilirubin < upper limit of normal (ULN) AST/SGOT < ULN Calcium < ULN

13. Ability to sign informed consent

14. Ability to attend follow-up visits

Exclusion Criteria:

1. Operable disease

2. Metastases to contra-lateral mediastinal lymph nodes

3. Distant metastases

4. KPS < 60

5. FEV1 < 1.2L

6. Previous RT to chest

7. Treatment with biological response modifiers or cytotoxic agents within four weeks prior to study entry

8. Participation in clinical trial using any investigational drug or device within four weeks prior to study entry

9. Major surgical procedure within two weeks prior to study entry

10. Serious comorbid condition, inclusive but not limited to myocardial infarction within previous six months, uncontrolled cardiac arrhythmias, uncontrolled angina pectoris, active infection including acute hepatitis

11. Serious complication of malignant condition

12. Previous or concurrent malignancy

13. Inadequate organ function as evidenced by the following peripheral blood counts or serum chemistries at study entry:

    Hemoglobin < 9.0 Gm/dL WBC count < 4.0x109/L Neutrophile count < 1.5 cells x 109/L, Platelet count < 100 x 109/L, Creatinine > 1.5 mg/dL Total bilirubin > ULN (upper limit of normal) AST/SGOT > ULN Version 1, May 12, 2010 Calcium > ULN

14. Inability to sign informed consent

15. Psychological, familial, sociological or geographical conditions which do not permit regular medical follow-up and compliance with the protocol