Related Experiment Video
Updated: Mar 23, 2026
Competing-Risk Nomogram for Predicting Cancer-Specific Survival in Multiple Primary Colorectal Cancer Patients after Surgery
Published on: September 27, 2024
MGMT in colorectal cancer: a promising component of personalized treatment
Le Zhang1,2,3, Jing Zeng1,4, Zhaolei Zeng1,5
1State Key Laboratory of Oncology in South China, Sun Yat-sen University Cancer Center, Collaborative Innovation Center for Cancer Medicine, 651# Dongfeng Road East, Guangzhou, 510060, People's Republic of China.
Abstract:
The identification of new, effective drugs is a pressing need in colorectal cancer (CRC) rescue therapy. Data examining O (6)-methylguanine-DNA-methyl transferase (MGMT) and its predictive role in temozolomide (TMZ) treatment in CRC are scarce. In this study, the effect of MGMT status on the cytotoxic sensitivity caused by TMZ was analyzed using cytology proliferation assays in colon cancer cell lines. MGMT protein expression was assessed with immunohistochemistry in 385 patients. Concordance between primary and metastatic sites and the role of MGMT status on survival were statistically analyzed. TMZ sensitivity was significantly affected by the level of MGMT protein expression. Of 385 cases, 13 (3.4 %) demonstrated loss of MGMT expression. However, low MGMT expression levels were significantly more common in signet ring cell carcinomas (p = 0.011). In 111 of 385 cases, the overall concordance of MGMT status between primary tumor and metastatic sites was 66.67 % (κ = 0.271, p < 0.001). The median progression-free survival was significantly different between groups with low or high MGMT expression for the irinotecan-based regimen (p = 0.025), but MGMT protein expression was not observed to be a prognostic factor. In conclusion, MGMT was an important in vitro predictor of TMZ activity in CRC. The rate of MGMT protein loss was low in metastatic CRC patients from China, and MGMT might be more commonly lost in signet ring cell carcinoma. The MGMT status at primary and metastatic sites was consistent, but the power of concordance was poor. Further study into these topics is warranted.
Insights
O(6)-methylguanine-DNA-methyltransferase (MGMT) levels predict temozolomide (TMZ) effectiveness in colorectal cancer (CRC). MGMT loss was rare, but more common in signet ring cell carcinomas, with poor concordance between primary and metastatic sites.
Area of Science:
- Oncology
- Molecular Biology
- Cancer Genetics
Background:
- Colorectal cancer (CRC) requires novel therapeutic strategies.
- The predictive role of O(6)-methylguanine-DNA-methyltransferase (MGMT) in temozolomide (TMZ) treatment for CRC is not well-established.
- Understanding MGMT's influence is crucial for optimizing CRC therapy.
Purpose of the Study:
- To investigate the effect of MGMT status on TMZ sensitivity in CRC.
- To analyze MGMT protein expression in a cohort of CRC patients.
- To assess the concordance of MGMT status between primary and metastatic sites and its prognostic value.
Main Methods:
- Cytology proliferation assays were used to determine TMZ sensitivity based on MGMT expression levels in colon cancer cell lines.
- Immunohistochemistry was employed to assess MGMT protein expression in 385 CRC patients.
- Statistical analyses were performed to evaluate concordance and survival outcomes.
Main Results:
- MGMT protein expression significantly influenced TMZ sensitivity in vitro.
- Loss of MGMT expression was observed in only 3.4% of cases, but was more frequent in signet ring cell carcinomas (p=0.011).
- Concordance of MGMT status between primary and metastatic sites was 66.67% (κ=0.271, p<0.001), indicating poor agreement. Progression-free survival differed significantly with MGMT status in irinotecan-based regimens (p=0.025), though MGMT was not a prognostic factor.
Conclusions:
- MGMT is a significant in vitro predictor of TMZ activity in CRC.
- MGMT protein loss is infrequent in metastatic CRC patients from China, with a higher prevalence in signet ring cell carcinoma.
- While MGMT status is generally consistent between primary and metastatic sites, the concordance is poor, necessitating further investigation.
More Related Videos
12:45Robot-assisted Total Mesorectal Excision and Lateral Pelvic Lymph Node Dissection for Locally Advanced Middle-low Rectal Cancer
Published on: February 12, 2022
04:22Application of Laparoscopic Hepatectomy Combined with Intraoperative Microwave Ablation in Colorectal Cancer Liver Metastasis
Published on: March 3, 2023
Related Concept Videos
01:21Inflammatory Bowel Disease V: Surgical Management
Here are some common surgical interventions for IBD:
01:25Endoscopic Procedures II: Colonoscopy
01:26Peptic Ulcer Disease IV: Management
The therapeutic approach involves ensuring adequate rest, implementing drug therapy, promoting smoking cessation, making dietary modifications, and emphasizing long-term follow-up care.
Pharmacological management
The prevailing therapy for peptic ulcers involves a combination of managing the patient's current...
01:30Inflammatory Bowel Disease III: Diagnostic Studies and Management I-Nutritional Therapy
Diagnostic studies
A colonoscopy is the definitive screening test, distinguishing ulcerative colitis from other colon diseases with similar symptoms. During a colonoscopy test, inflamed mucosa with exudate ulcerations can be observed, and biopsies are taken to determine the histologic characteristics of the...
02:56Treatment Resistent Cancers
02:56Treatment Resistant Cancers