• discovery and validation of biomarker predicting gastric cancer chemotherapy response

  • Analysis for expression level of mRNA using Next generation sequencing in gastric cancer tissue by chemotherapy response
  • Analysis for expression level of miRNA using Next generation sequencing in gastric cancer tissue and blood by chemotherapy response
  • Validation of mRNA and miRNA using qRT-PCR in multiple independent cohort

• Biological biomarkers-clinical factor combined prediction model of gastric cancer chemotherapy response

• discovery and validation of biomarker predicting gastric cancer chemotherapy response

  • Analysis for expression level of mRNA in fresh frozen gastric cancer tissue by chemotherapy response (A) method of mRNA expression measurement: RNA sequencing (B) study group Palliative chemotherapy (inoperable patients)

    • institutional primary Chemotherapy regimen (XP or Xelox)

      1. response group

      2. progression group

         Post-OP adjuvant chemotherapy

    • institutional primary Chemotherapy regimen

      1. complete response group
      2. non-responder group
      1. and 2) groups: age, sex, regimen matched

  • Analysis for expression level of miRNA using Next generation sequencing in gastric cancer tissue and blood by chemotherapy response (A) method of mRNA expression measurement: RNA sequencing (B) study group

    • the same patients in mRNA sequencing

  • Validation of mRNA and miRNA in multiple independent cohort method of measurement of RNA expression: qRT-PCR

• Biological biomarkers-clinical factor combined prediction model of gastric cancer chemotherapy response combination of biologic biomarker and clinical factors to predict the chemotherapy response in gastric cancer

Inclusion Criteria:

• new gastric cancer patients who has scheduled to start 1st cycle of chemotherapy
• patients who agreed this study and voluntarily assigned the informed consents.

Exclusion Criteria:

• patients who refused the study.
• patients who have other cancers
• heavy alcoholics

<Next generation sequencing analysis> (A) palliative chemotherapy

1. responder (n=15)
2. progression (n=15)

(B) adjuvant chemotherpay

1. complete response (n=15)
2. non-responder (n=15)

<qRT-PCR analysis> (Experimental set) (A) palliative chemotherapy

1. responder (n=60)
2. progression (n=60)

(B) adjuvant chemotherpay

1. complete responder (n=60)
2. non-responder (n=60)

(Validation set) (A) palliative chemotherapy

1. responder (n=40)
2. progression (n=40)

(B) adjuvant chemotherpay

1. complete responder (n=40)
2. non-responder (n=40)

1. and 2) groups: age, sex, regimen matched. Therefore this study will be nested case-control study. We will enroll 800 patients and then we will matched age, sex, and regimen in each group.