Phase II Trial of Vistusertib（AZD2014） Single Agent in TSC1or 2 Null or TSC 1/2 Mutation Solid Cancer Patients Refractory to Standard Chemotherapy

Inclusion Criteria: 1. Advanced solid cancers (including histologically or cytologically documented gastric cancer, colorectal cancer, hepatoma, biliary tract cancers, pancreatic cancer and rare cancers.) that has progressed after standard chemotherapy. 2. Provision of tumor sample (from either a resection or biopsy) 3. Patients with TSC1or 2 null or TSC 1/2 mutation through IHC. 4. Patients must have acceptable bone marrow, liver and renal function measured within 28 days prior to administration of study treatment as defined below: * Haemoglobin ≥9.0 g/dL (transfusion allowed) * Absolute neutrophil count (ANC) ≥ 1.5 x 109/L * White blood cells (WBC) \> 3 x 109/L * Platelet count ≥100 x 109/L (transfusion allowed) * Total bilirubin ≤ 1.5 x institutional upper limit of normal (ULN) * AST (SGOT)/ALT (SGPT) ≤ 2.5 x institutional upper limit of normal unless liver metastases are present in which case it must be ≤ 5x ULN * Serum creatinine ≤1.5 x institutional ULN Exclusion Criteria: 1. Any previous treatment with PIK3CA, AKT or mTOR inhibitor or agents with mixed PI3K / mTOR activity. 2. For vistusertib(AZD2014): Exposure to potent or moderate inhibitors or inducers of CYP3A4/5 if taken within the stated washout periods before the first dose of study treatment With the exception of alopecia, any ongoing toxicities (\>CTCAE grade 1) caused by previous cancer therapy. 3. Intestinal obstruction or CTCAE grade 3 or grade 4 upper GI bleeding within 4 weeks before the enrollment.