AIMS: The aim of this study was to analyze the mutations in genes involved in CRC including MLH1, MSH2, KRAS, and APC genes.
METHODS: A total of 76 patients were recruited. We used the polymerase chain reaction-denaturing high-performance liquid chromatography for the detection of mutations in the mismatch repair (MMR) and APC genes and the PCR single-strand conformation polymorphism for screening of the KRAS gene mutations.
RESULTS: We identified 17 types of missense mutations in 38 out of 76 patients in our patients. Nine mutations were identified in the APC gene, five mutations were detected in the KRAS gene, and two mutations were identified in the MSH2 gene. Only one mutation was identified in MLH1. Out of these 17 mutations, eight mutations (47 %) were predicted to be pathogenic. Seven patients were identified with multiple mutations (3: MSH2 and KRAS, 1: KRAS and APC, 1: MLH1 and APC, 2: APC and APC).
CONCLUSIONS: We have established the PCR-DHPLC and PCR-SSCP for screening of mutations in CRC patients. This study has given a snapshot of the spectrum of mutations in the four genes that were analyzed. Mutation screening in patients and their family members will help in the early detection of CRC and hence will reduce mortality due to CRC.
METHODS: In this study, conducted in Malaysia, we evaluated the seven-gene biomarker panel validated in a North American population using blood samples collected from local patients. The panel employs quantitative RT-PCR (qRT-PCR) to analyze gene expression of the seven biomarkers (ANXA3, CLEC4D, TNFAIP6, LMNB1, PRRG4, VNN1 and IL2RB) that are differentially expressed in CRC patients as compared with controls. Blood samples from 210 patients (99 CRC and 111 controls) were collected, and total blood RNA was isolated and subjected to quantitative RT-PCR and data analysis.
RESULTS: The logistic regression analysis of seven-gene panel has an area under the curve (AUC) of 0.76 (95% confidence interval: 0.70 to 0.82), 77% specificity, 61% sensitivity and 70% accuracy, comparable to the data obtained from the North American investigation of the same biomarker panel.
CONCLUSIONS: Our results independently confirm the results of the study conducted in North America and demonstrate the ability of the seven biomarker panel to discriminate CRC from controls in blood samples drawn from a Malaysian population.
PATIENTS AND METHODS: APEC was a nonrandomized phase 2 trial conducted in the Asia-Pacific region. Patients (n = 289) received once-every-2-weeks cetuximab with investigator's choice of chemotherapy (FOLFOX or FOLFIRI). The primary end point was best confirmed overall response rate (BORR); progression-free survival (PFS) and overall survival (OS) were secondary end points. Early tumor shrinkage (ETS) and depth of response (DpR) were also evaluated.
RESULTS: In the KRAS wt population, BORR was 58.8%, median PFS 11.1 months, and median OS 26.8 months. Expanded RAS mutational analysis revealed that patients with RAS wt mCRC had better outcomes (BORR = 64.7%; median PFS = 13.0 months; median OS = 28.4 months). The data suggest that ETS and DpR may be associated with survival outcomes in the RAS wt population. Although this study was not designed to formally assess differences in outcome between treatment subgroups, efficacy results appeared similar for patients treated with FOLFOX and FOLFIRI. There were no new safety findings; in particular, grade 3/4 skin reactions were within clinical expectations.
CONCLUSION: The observed activity and safety profile is similar to that reported in prior first-line pivotal studies involving weekly cetuximab, suggesting once-every-2-weeks cetuximab is effective and tolerable as first-line therapy and may represent an alternative to weekly administration.