scholarly journals IMPACT OF KRAS MUTATIONS IN CLINICAL FEATURES IN COLORECTAL CANCER

Author(s):  
Renato Morato ZANATTO ◽  
Gianni SANTOS ◽  
Júnea Caris OLIVEIRA ◽  
Eduardo Marcucci PRACUCHO ◽  
Adauto José Ferreira NUNES ◽  
...  

ABSTRACT Background: KRAS mutations are important events in colorectal carcinogenesis, as well as negative predictors of response to EGFR inhibitors treatment. Aim: To investigate the association of clinical-pathological features with KRAS mutations in colorectal cancer patients treated. Methods: Data from 69 patients with colorectal cancer either metastatic at diagnosis or later, were retrospectively analyzed. The direct sequencing and pyrosequencing techniques were related to KRAS exon 2. The mutation diagnosis and its type were determined. Results: KRAS mutation was identified in 43.4% of patients. The most common was c.35G>T (p.G12V), c.35G>A (p.G12D) and c.38G>A (p.G13D). No correlation was found between KRAS mutation and age (p=0.646) or gender (p=0.815). However, mutated group had higher CEA levels at admission (p=0.048) and codon 13 mutation was associated with involvement of more than one metastatic site in disease progression (p=0.029). Although there was no association between primary tumor site and mutation diagnosis (p=0.568), primary colon was associated with worse overall survival (p=0.009). Conclusion: The KRAS mutation was identified in almost half of patients. Mutated KRAS group had higher levels of CEA at admission and the mutation at codon 13 was associated with involvement of more than one metastatic site in the course of the disease. Colon disease was associated with the worst overall survival.

2021 ◽  
pp. 172460082110171
Author(s):  
Ye Yuan ◽  
Yingting Liu ◽  
Ye Wu ◽  
Junling Zhang ◽  
Chunti Shen ◽  
...  

Background: The KRAS mutations are high-frequency somatic mutations found in colorectal cancer patients from Western and Asian countries however, with the exception of exon 2 of KRAS, other prevalence and prognostic values have not been adequately assessed in Asian patients. The aim of this study was to determine the mutation frequencies of whole exon mutations of KRAS in Chinese colorectal cancer patients and to investigate their impact on prognosis. Methods: A total of 7189 tumor tissue samples (iCohort) were subjected to next-generation sequencing for detection of KRAS mutations. All pathologic or likely pathologic mutations of KRAS were considered. In addition, clinical features and prognostic dates were collected from 145 patients at The Third Affiliated Hospital of Soochow University, China (sCohort) and used droplet digital™ polymerase chain reaction to detect KRAS mutations. Results: In the iCohort, 2706 patients (37.6%) were confirmed harboring KRAS mutations. The most frequent of these mutations were G12D (32.19%), G12V (17.96%), and G13D (17.59%). In the sCohort, 51 colorectal cancer patients (35.17%) had KRAS mutations, among which KRAS G12D (64.71%), G13D (29.41%), and G14D (3.92%) were high-frequency. The KRAS mutations were associated with shorter median overall survival than wild-type tumors (69 vs. 55 months; HR 1.80; 95% Cl 1.22, 2.64; P=0.0003). In the Cox multivariate analysis, age (HR 1.562; 95% Cl 1.10, 2.22; P=0.013), tumor differentiation (HR 0.417; 95% Cl 0.19, 0.90; P=0.026), and KRAS mutation (HR 1.897; 95% Cl 0.19, 0.90; P=0.001) remained independent predictors of shorter overall survival. Among the common KRAS mutations, G12D was significantly associated with shorter overall survival (HR 2.17; 95% Cl 1.31, 3.58; P < 0.0001) compared with KRAS wild-type patients. Conclusions: Our findings indicate that KRAS genes are frequently mutated, and over 30% harbored the KRAS G12D mutation subtype. We found that the KRAS G12D mutation is associated with inferior survival and is a biomarker of poor prognosis in Chinese patients. Our data emphasize the importance of molecular features in colorectal cancer patients, which could potentially be improved by G12D-specific related inhibitors.


2019 ◽  
Author(s):  
Muhammad Awidi ◽  
Nidaa Ababneh ◽  
Maha Shomaf ◽  
Feras Al Fararjeh ◽  
Laila Owaidi ◽  
...  

Abstract Background A constitutively active RAS protein in the absence of stimulation of the epidermal growth factor receptor (EGFR) is the result of mutations in KRAS and NRAS genes. Mutations in the KRAS exon 2 and outside exon 2 have been found to predict the resistance to anti-EGFR monoclonal therapy. A substantial proportion of metastatic colorectal cancer cases (mCRC) exhibit RAS mutations outside KRAS exon 2, particularly in KRAS exon 3 and 4 and NRAS exons 2, 3. No data about RAS mutations outside KRAS exon 2 are available for Jordanian patients with mCRC. We aim to study the molecular spectrum, frequency, and distribution pattern of KRAS and NRAS mutations in Jordanian patients with mCRC. Methods A cohort of 190 Jordanian metastatic colorectal cancer patients were enrolled in the trial. We detected mutations in exon 2 of the KRAS and NRAS gene as well as mutations outside of exon 2 using the StripAssay technique. The KRAS StripAssay covered 29 mutations and 22 NRAS mutations. Results Mutations were observed in 92 (48.42%) cases, and KRAS exon 2 accounted for 76 cases (83.69%). KRAS G12D was the most common mutation, occurring in 18 cases, followed by KRAS G12A in 16 cases, and G12T in 13 cases. Mutations outside of KRAS exon 2 represented 16.3% of the mutated cases. Among those, 6 cases (6.48%) carried mutations in NRAS exon 2, 3 and 10 cases (10.87%) in KRAS exon 3 and 4. Conclusion The frequency of NRAS and KRAS mutations outside of exon 2 appears to be higher in Jordanian patients in comparison with patients from western countries. KRAS mutations outside of exon 2 should be tested routinely to identify patients who should not be treated with anti-EGFR antibodies.


2007 ◽  
Vol 35 (4) ◽  
pp. 450-457 ◽  
Author(s):  
K Kimura ◽  
T Nagasaka ◽  
N Hoshizima ◽  
H Sasamoto ◽  
K Notohara ◽  
...  

Codon 12 and 13 mutations in 170 colorectal cancer (CRC) and 66 gastric cancer (GC) specimens were analysed by an ‘enriched’ polymerase chain reaction–restriction fragment length polymorphism (PCR–RFLP) method. All identified mutations were verified by direct sequencing of the second PCR products. Among the 170 CRC specimens, mutations were identified in 47 (28%) and 13 (7.6%) cases in codons 12 and 13, respectively. In the 66 GC specimens examined, however, mutations in codons 12 and 13 were only detected in two (3.0%) and one (1.5%) cases, respectively. Mutations in both codon 12 and 13 were found in 3/170 (1.8%) CRCs and 1/66 (1.5%) GCs. Duplicate mutations were never identified in the same allele, which was confirmed by direct sequencing of the second amplified products. The majority of colorectal and gastric cancer cells with KRAS mutations are homogeneous because they have the same KRAS mutation. A few colorectal or gastric cancers, however, showed heterogeneity, as verified by the fact that single mutations were identified in the same allele.


2013 ◽  
Vol 31 (15_suppl) ◽  
pp. 3522-3522
Author(s):  
Vlad Calin Popovici ◽  
Eva Budinska ◽  
Arnaud Roth ◽  
Fred Bosman ◽  
Sabine Tejpar ◽  
...  

3522 Background: The BRAF and KRAS mutations have been proposed as prognostic markers in colorectal cancer (CRC). Of them, only the BRAF V600E mutation has been validated as prognostic for overall survival and survival after relapse, while the value of KRAS mutation is still unclear. Methods: In a cohort of 1423 stage II-III patients from the PETACC-3 clinical trial, the prognostic value of the BRAF and KRAS mutations was retrospectively assessed in all possible stratifications defined by the 5 factors (T and N stage, tumor site and grade, and microsatellite instability status), by log rank test for overall survival (OS), relapse-free survival (RFS), and survival after relapse (SAR). The presence of interactions was tested by Wald test. The significance level was set to 0.01 for Bonferroni-adjusted p-values (P*), and a second level for a trend towards statistical significance was set at 0.05 for unadjusted p-values (P). Results: BRAF mutation was a marker of poor OS only in microsatellite stable (MSS) and left-sided tumors, with no prognostic value in microsatellite instable (MSI-H) or right-sided tumors. In MSS/left-sided tumors, BRAF mutation represents a marker of higher risk than previously reported: OS HR=6.4 [95% CI: 3.6-11.5], P* < 0.0001. For SAR, BRAF was prognostic in more stratifications, with higher risk in MSS/left-sided tumors (HR=3.9 [95% CI: 2.1-7.2], P* = 0.0002) than in MSS/right-sided (HR=2.3 [95% CI: 1.2-4.4], P=0.01). A novel observation was that BRAF mutation was prognostic also for RFS, but only in MSS/left-sided tumors (HR=3.6 [95% CI:2-6.3], P*=0.0005]). Additionally, heterogeneity in OS and RFS among BRAF mutants was observed. In general, KRAS mutation did not reach the significance level required, but showed a trend to become a prognostic marker for RFS in MSS tumors with early lymph node involvement (N1) (HR=1.6 [95% CI:1.1-2.2], P=0.01). Conclusions: The prognostic utility of the BRAF and KRAS mutations has to be interpreted in the context of other factors. For the BRAF mutation, a clear interaction with MSI status and tumor site was observed, with BRAF mutation indicating a much higher risk in MSS/left-sided tumors than previously considered.


2015 ◽  
Vol 68 (4) ◽  
pp. 265-269 ◽  
Author(s):  
Umberto Malapelle ◽  
Roberta Sgariglia ◽  
Alfonso De Stefano ◽  
Claudio Bellevicine ◽  
Elena Vigliar ◽  
...  

AimsPatients with colorectal cancer harbouring KRAS mutations do not respond to antiepidermal growth factor receptor (anti-EGFR) therapy. Community screening for KRAS mutation selects patients for treatment. When a KRAS mutation is identified by direct sequencing, mutant and wild type alleles are seen on the sequencing electropherograms. KRAS mutant allele-specific imbalance (MASI) occurs when the mutant allele peak is higher than the wild type one. The aims of this study were to verify the rate and tissue distribution of KRAS MASI as well as its clinical relevance.MethodsA total of 437 sequencing electropherograms showing KRAS exon 2 mutation was reviewed and in 30 cases next generation sequencing (NGS) was also carried out. Five primary tumours were extensively laser capture microdissected to investigated KRAS MASI tissue spatial distribution. KRAS MASI influence on the overall survival was evaluated in 58 patients. In vitro response to anti-EGFR therapy in relation to different G13D KRAS MASI status was also evaluated.ResultsOn the overall, KRAS MASI occurred in 58/436 cases (12.8%), being more frequently associated with G13D mutation (p=0.05) and having a heterogeneous tissue distribution. KRAS MASI detection by Sanger Sequencing and NGS showed 94% (28/30) concordance. The longer overall survival of KRAS MASI negative patients did not reach statistical significance (p=0.08). In cell line model G13D KRAS MASI conferred resistance to cetuximab treatment.ConclusionsKRAS MASI is a significant event in colorectal cancer, specifically associated with G13D mutation, and featuring a heterogeneous spatial distribution, that may have a role to predict the response to EGFR inhibitors. The foreseen implementation of NGS in community KRAS testing may help to define KRAS MASI prognostic and predictive significance.


2016 ◽  
Vol 34 (4_suppl) ◽  
pp. 588-588
Author(s):  
In Kyu Lee ◽  
Sung-Bong Choi ◽  
DaeYoung Cheung ◽  
Jin Il Kim

588 Background: To determine the clinical significance of KRAS mutation and ERCC1 overexpression as a predictive factor of resistance in oxaliplatin based treatment. Methods: We retrospectively analyzed the clinicopathologic features, status of KRAS mutation and ERCC1 overexpression of 386 colorectal cancer patients who received curative intent surgery. Among them 84 patients were treated by FOLFOX regimen as the first line. Their disease-free survival and overall survival according to the KRAS and ERCC1 were analyzed. Results: About a quarter of patients (25.5%) were represented KRAS wild type with ERCC1 overexpression. Among the patients who treated by FOLFOX regimen, 73 patients were evaluated both of the KRAS and ERCC1. There were no significant differences of disease-free survival and overall survival according to KRAS status and ERCC1 expression each. Under the subgroup analysis, overall survival of ERCC1 overexpression group in wild type KRAS was poor than ERCC1 negative group (p=.029), but no significant difference was in mutant KRAS group (p=.671). Conclusions: Our results suggest that the KRAS wild type with ERCC1 overexpression would be associated with the resistance of oxaliplatin.If oxaliplatin based chemotherapy would beconsidered, status of KRAS mutation and ERCC1 overexpression should be evaluated.


2017 ◽  
Vol 4 (10) ◽  
pp. 1693 ◽  
Author(s):  
Mehrdad Payandeh ◽  
Nasrin Amirifard ◽  
Masoud Sadeghi ◽  
Babak Shazad ◽  
Negin Farshchian ◽  
...  

Colorectal cancer (CRC) is one of the most common cancers in the World that KRAS mutations are considered as a key step in the progression of CRC. This meta-analysis study aimed to evaluate the prevalence of KRAS mutations in CRC patients in Iran. Six online databases including PubMed, Science direct, Scopus, Web of science, Cochran Library, and Scientific Information Database (SID) were searched systematically up to January 2017. A random-effects meta-analysis was used to calculate the estimation of the prevalence of KRAS mutations in CRC patients by the event rate (ER) with 95% confidence interval (95%CI). Out of 82 articles identified from the search, eleven studies included and analyzed for meta-analysis study. The studies included 1814 CRC patients that mean age of the patients was 57.5 years. The pooled ER of the studies for estimation of the prevalence of KRAS mutation in CRC patients was 32.8% (95%CI=28.7-37.3%). The pooled ER of the studies for the prevalence of codon 12 mutation was 72.5% (95%CI=59.8-82.3%) and for codon 13 mutation was 20% (95%CI=14.6-26.7%). The results showed that the prevalence of KRAS mutation in Iran was different with more studies that therefore the geographical area and race can impact on the prevalence of KRAS mutation in CRC patients. Also, codon 12 had the most prevalence among mutant codons, followed by codon 13 that Gly to Asp and Gly to Val were the most mutations in codon 12.   Peer Review Details Peer review method: Single-Blind (Peer-reviewers: 02) Peer-review policy Plagiarism software screening?: Yes Date of Original Submission: 07 September 2017 Date accepted: 02 October 2017 Peer reviewers approved by: Dr. Lili Hami Editor who approved publication: Dr. Phuc Van Pham  


Acta Medica ◽  
2019 ◽  
Vol 50 (1) ◽  
pp. 20-25
Author(s):  
Minh Thuc Vu Thi ◽  
Van Thieu Le ◽  
Quang Huy Huynh ◽  
Minh Duc Nguyen

Objective: KRAS mutation occurs in 30% to 50% of colorectal cancers. The aim of our study was to determine the frequency of KRAS mutations among patients with colorectal cancer; and the relationship with clinicopathologic features. Materials and Methods: 79 colorectal cancer cases at a hospital in Hai Phong of Vietnam were collected, including 45 colon cancer and 34 rectal cancer during January 2010 and July 2012. PCR amplification and DNA sequencing were used to detect mutations in exon 2 of KRAS gene. The study was based on informed consent and approval by the Ethics Committee of Viet Tiep Hospital. Results: KRAS mutation was found in 40.4% (225/557) colorectal cancer. All mutation locations were in codon 12. There was significant association (p < 0.05) between KRAS mutations, tumor size and tumor stage. No significant association was observed between KRAS mutations and gender, tumor location, tumor grade or histologic presence of mucin (p>0.05). Conclusion: Determining the KRAS mutational status of tumor samples has become an essential tool for managing patients with colorectal cancers Keywords: colorectal cancer, KRAS gene mutation, clinicopathology.


2009 ◽  
Vol 27 (15_suppl) ◽  
pp. e15048-e15048
Author(s):  
T. Yokota ◽  
K. Muro ◽  
N. Shibata ◽  
T. Ura ◽  
D. Takahari ◽  
...  

e15048 Background: The activating KRAS mutation is an important predictive marker for anti-EGFR therapy against colorectal cancer (CRC), although valid assays using pathological specimens have not been yet established. We present a rapid, sensitive assay for KRAS genotyping using small biopsy specimens. Methods: We used Cycleave PCR to detect the KRAS mutation in CRC with a chimeric DNA-RNA-DNA probe labeled with fluorescent dye and quencher, with results obtained within 4 hours. Template DNA was extracted from formalin-fixed, paraffin-embedded specimens, which are surgically resected or biopsied in clinical practice. Results: To evaluate Cycleave PCR accuracy for detecting the KRAS mutation, we compared with results of reverse transcriptase-PCR-coupled direct sequencing (RT-PCR-DS) of metastatic lung tumor specimens from CRC patients. KRAS mutations were present in 40 (43%) of 94 patients, including 28 (30%) and 8 (9%) in codon 12 and codon 13 mutations, respectively. Concordant results between Cycleave PCR and RT-PCR-DS in KRAS codon 12 and 13 were found in 35/36 (97%) and 23/23 (100%), respectively. We also applied this method to surgical specimens in clinical practice. Although 8 from 73 patients (11%) could not be evaluated with Cycleave PCR, corresponding biopsy specimens could be used alternatively. Because biopsy specimens were fixed by formalin for a shorter period, fixation of surgical specimens for longer time may have contributed to PCR failure. Indeed, over- fixation by formalin impaired PCR amplification of KRAS in time-dependently. Furthermore, results of 4 randomly selected biopsy specimens using Cycleave PCR were consistent with those of surgical specimens. Conclusions: Cycleave PCR even using biopsy specimens is accurate, rapid, and useful to detect KRAS mutations in CRC patients. This study also called attention to specimen selection, as over-fixation by formalin may lead to failure of the gene examination due to template DNA fragmentation. This method can be applied to examine BRAF genotyping as well as KRAS. KRAS/BRAF genotyping by Cycleave PCR leads to individualized therapy using cetuximab for CRC patients. No significant financial relationships to disclose.


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