Colorectal Cancers, DNA Methylation, Immunotherapy
Conditions
Brief summary
The goal of this observational study is to assess lymphocyte levels in colorectal cancer patients using DNA methylation levels in tissues or blood. The main questions it aims to answer are: Can DNA methylation features calculate lymphocyte levels? Can the calculated lymphocyte levels assess the efficacy and prognosis of immunotherapy?
Interventions
OTHERquantitative analysis of DNA methylation at single-base resolution (QASM)
qPCR-based quantitative analysis for single-base methylation (QASM) The methylation percentage of each candidate CpG site was determined in multiple cohorts using a MethyLight-based QASM assay that has been developed and validated in our previous work. In short, the bisulfite-converted DNA was amplified, in which we exploited the locus-specific PCR primers flanking a pair of methylated and unmethylated probes labeled with the fluorescent dyes 6-carboxyfluorescein (6-FAM) and 2-chloro-7phenyl-1,4-dichloro-6-carboxyfluorescein (VIC), respectively. The methylation percentage was calculated by methylation/(methylation+unmethylation)×100%. QASM was performed using the Applied Biosystems QuantStudio 7 Flex Real-Time PCR System (Thermo).
Sponsors
Sixth Affiliated Hospital, Sun Yat-sen University
Study design
Observational model
COHORT
Time perspective
RETROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
18 Years to 80 Years
Healthy volunteers
No
Inclusion criteria
1. Diagnosed with colorectal cancer by colonoscopy pathology and deemed eligible for immunotherapy after assessment. 2. Neoadjuvant immunotherapy regimen includes PD-1 or anti-PD-L1. 3. R0 resection is performed after neoadjuvant immunotherapy. 4. Complete immunotherapy efficacy assessment data and follow-up data are available. 5. The tissue bank stores the required whole blood and tissue samples for the experiment.
Exclusion criteria
1. Concurrent other malignancies. 2. Neoadjuvant immunotherapy not conducted according to the standard protocol. 3. Severe adverse chemotherapy reactions that lead to the discontinuation of immunotherapy midway. 4. Lack of complete neoadjuvant chemotherapy efficacy assessment data or follow-up data. 5. The tissue bank does not store the required whole blood or tissue samples for the experiment. 6. Patients with concurrent other immune system diseases.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Complete Response Rate | From the date of neoadjuvant therapy until the date when the surgical specimen pathology results are obtained, the duration of neoadjuvant therapy is approximately half a year, with a maximum of one year. | The complete response rate refers to the percentage of patients who experience a complete disappearance of their disease after treatment. |
Countries
China
Outcome results
None listed