Project description:Samples were prospectively collected during colonoscopic examination from 46 rectal cancer patients before starting preoperative chemoradiotherapy. The expression profiles were determined using Affymetrix Human Genome U133 Plus 2.0 arrays. Comparison between the sample groups allow to identify a set of discriminating genes that can be used for prediction of the response to radiotherapy in rectal cancer. Specimens from 46 rectal cancer patients who approved to receive preoperative chemoradiotherapy were studied. We prospectively collected biopsy specimens during colonoscopic examination from rectal cancer before starting preoperative chemoradiotherapy. Specimens from tumors were snap-frozen in liquid nitrogen and stored at -80 C until use. Paralleled tumor specimens were formalin fixed and paraffin embedded for histologic examination and other specimens were used for RNA extraction. RNA was extracted from tumor tissue using frozen samples. The patients provided written, informed consent to the collection of specimens, and the local Ethics Committee approved the study protocol. All patients received a total dose of 50.4 Gy of radiation, UFT(300-500mg/day) and LV (75mg/day) and underwent standardized curative resection, following an interval of 4 weeks after chemoradiotherapy.
Project description:Samples were prospectively collected during colonoscopic examination from 46 rectal cancer patients before starting preoperative chemoradiotherapy. The expression profiles were determined using Affymetrix Human Genome U133 Plus 2.0 arrays. Comparison between the sample groups allow to identify a set of discriminating genes that can be used for prediction of the response to radiotherapy in rectal cancer.
Project description:Cancer-associated fibroblasts (CAFs) are an important component of the desmoplastic stroma in rectal cancer. Preoperative chemoradiotherapy plays a pivotal role in the management of locally advanced rectal cancer. Patient-derived CAFs were used to evaluate the response to radiotherapy and its consequent impact on colorectal cancer cells (COLO320DM). COLO320DM cells were seeded and 24 hours later 1.8Gy irradiated. Subsequently, 24h later COLO320DM cells were treated with the secretome of 10x 1.8Gy irradiated CAFs or sham treated CAFs in 0.5% of serum. RNA was isolated 6 hours or 48 hours later.
Project description:The identification of surrogate single nucleotide polymorphism (SNP) markers that can predict responses to preoperative chemoradiotherapy (CRT) in rectal cancer patients. Genome-wide association studies in clinical populations are theoretically capable of identifying markers that are capable of tumor regression after CRT. We used Affymetrix’s SNP Array 6.0 to detail genetic polymorphism of patient’s group showing differential responsiveness to preoperative CRT and profiled SNP biomarkers.
Project description:Emerging evidence suggests that an increased density of pre-treatment CD8+ tumor-infiltrating lymphocytes (TILs) is associated with good response to chemoradiotherapy (CRT) in patients with locally advanced rectal cancer. However, the significance of T-cell complexity in the clinical setting remains unknown. High-throughput T-cell receptor (TCR) β sequencing was applied to quantify the TCR repertoire of pre-treatment biopsies from 67 patients with advanced rectal cancer receiving preoperative CRT. Changes in TCR repertoire before and after CRT were also analysed in 23 patients.
Project description:Prediction of sensitivity of rectal cancer cells in response to preoperative chemoradiotherapy by DNA microarray analysis of gene expression profiles.
Project description:The treatment strategy of rectal cancer has substantially changed in recent decades. Historically postoperative chemoradiotherapy (CRT) was considered to be the first-line therapy for stage II and III rectal cancers. However, the preoperative CRT is now considered to be the optimal therapy regimen for locally advanced rectal ancer due to its improved local control, reduced toxicity, and increased rate of sphincter preservation. Our study established a clinically practical multi-class prediction model by adopting a novel strategy that applies two separate prediction models (MI and TO predictor) sequentially to a patient to predict the response. For promising clinical practice, we validated our model in a published dataset, which is completely independent dataset from ours. This study suggests a clinically plausible prediction model that correctly infers the preoperative CRT response of patients with high accuracy based on 163 gene signatures we identified. Total RNAs were isolated from primary rectal tumor tissues of 69 patients who underwent chemoradiation therapy (CRT). These patients are classified into four different CRT responses: minimal response (MI), moderate response (MO), near total response (NT) and total response (TO). All the RNAs were subjected to microarray analysis using Affymetrix GenChip arrays.
Project description:The treatment strategy of rectal cancer has substantially changed in recent decades. Historically postoperative chemoradiotherapy (CRT) was considered to be the first-line therapy for stage II and III rectal cancers. However, the preoperative CRT is now considered to be the optimal therapy regimen for locally advanced rectal ancer due to its improved local control, reduced toxicity, and increased rate of sphincter preservation. Our study established a clinically practical multi-class prediction model by adopting a novel strategy that applies two separate prediction models (MI and TO predictor) sequentially to a patient to predict the response. For promising clinical practice, we validated our model in a published dataset, which is completely independent dataset from ours. This study suggests a clinically plausible prediction model that correctly infers the preoperative CRT response of patients with high accuracy based on 163 gene signatures we identified.
Project description:Biopsy specimens were collected from rectal cancer before starting preoperative radiotherapy.The expression profiles were determined using Affymetrix Human Genome U95 version 2 arrays.Comparison between the sample groups allow to identify a set of discriminating genes that can be used for characterization of responders and nonresponders to preoperative radiotherapy in rectal cancer. Keywords: repeat