Evaluation of Consistency of PDX Model for Predicting Therapeutic Effect of Gastric Cancer

The goal of this study is to compare the tumor response in gastric cancer patients given neoadjuvant chemotherapy with the corresponding result obtained from zebrafish patient-derived tumor xenograft(PDX) model given the same regimen. The main question it aims to answer is whether this PDX model of zebrafish could accurately predict the effect of chemotherapy in advanced gastric cancer. Participants will be given the standard neoadjuvant treatment administrated by their own doctors and tumor response will be observed and recorded. Meanwhile, tumor samples derived from patients before chemotherapy will be transplanted to zebrafish and the same regimen will be given to the PDX models correspondingly. The tumor response data both from clinical practice and PDX model platform will be analysed and compared to evaluate the power of this zebrafish model platform in drug efficiency prediction.

Inclusion Criteria:patients aged 18-75years,patients with gastric cancer confirmed by histology or cytology at first visit,patients with advanced tumor by imaging evaluation,patients with preoperative neoadjuvant therapy;Eastern Cooperative Oncology Group (ECOG) physical status score of 0 or 1;tolerance to chemotherapy in laboratory examination;hematology examination: no obvious signs of hematological diseases, ANC ≥1.5 × 109/L before enrollment; Platelet count ≥80 × 109/L, HB ≥90 g/L, WBC ≥3.0 × 109/L, and no bleeding tendency;biochemical examination: Total Bilirubin <1.5 times of upper limit of normal value, AST, ALT < 2.5 times of upper limit of normal value, creatinine < 1.5 times of upper limit of normal value;Exclusion Criteria:patients with inoperable advanced gastric cancer,patients with metastatic or primary gastric cancer,pregnant or lactating women,patients with a history of other malignancies in the last 5 years;for those with a history of uncontrolled epilepsy, central nervous system disease or mental disorders, the severity of the clinical condition was assessed by the investigator as impeding the signing of informed consent or affecting the patient's compliance with oral medication;clinically serious (i.e. active) heart disease, such as symptomatic coronary heart disease, NYHA Class II or more heart failure, or arrhythmias requiring medical intervention; Or a history of myocardial infarction within the last 12 months;severe diabetes-related complications, such as diabetic nephropathy, diabetic ketosis, etc.gastrointestinal obstruction or abnormal physiological function, or malabsorption syndrome, which may affect drug absorption;gastrointestinal bleeding in the last two weeks or at high risk of bleeding as judged by the investigator;patients with known peripheral nerve disease ≥ NCI-CTC AE Grade 1, but only with deep tendon reflexes (DTR) ;organ transplantation requires immunosuppressive therapy;the presence of any active, known or suspected autoimmune disease.uncontrolled severe infection or other severe concomitant diseasehypersensitivity to paclitaxel, Oxaliplatin, 5-FU, or any clinically useful anti-gastric cancer agent.