KRAS, NRAS, BRAF, PIK3CA, and AKT1 signatures in colorectal cancer patients in south-eastern Romania.

Somatic mutations in the oncogenes of the epidermal growth factor receptor signaling pathway play vital roles in colorectal carcinogenesis and have been closely linked with clinical resistance to monoclonal therapy. In this study, we have analyzed the mutation frequencies of 5 genes and compared the genetic findings with clinicopathological variables in order to determine diagnostically relevant alterations and compare these findings with those of other studies In our Sanger sequencings, KRAS (exons 2, 3, and 4), NRAS (exons 2, 3, and 4), PIK3CA (exons 9 and 20), BRAF (exon 15), AKT1 (exon 2) genes, and microsatellite instability (MSI) status were analyzed using an ABI 3500 analyzer in a cohort of 58 Romanian colorectal cancer (CRC) patients who underwent surgical resection at Emergency County Clinical Hospital in Constanța, Romania. In our series, mutation rates of KRAS, BRAF, PIK3CA, and AKT1 genes were 39.63%, 8.62%, 6.88%, and 3.44%, respectively. By contrast, we did not find any tumor harboring mutation in the NRAS gene. Notably, the KRAS and PIK3CA mutations were not mutually exclusive, 1 patient harbored 2 mutations in exon2, codon 12 (Gly12Val) of KRAS and exon 20, codon 1047 (His1047Arg) of PIK3CA. The finding of our study are generally consistent with data found in the literature. Regarding to clinicopathological variables, mutation of KRAS was associated with distant metastasis at the time of diagnosis, while mutation of BRAF was significantly associated with MSI-H in contrast with MSI-L/MSS tumors. Moreover, PIK3CA mutation tends to be located in the proximal segment of the colon and to be well/moderately differentiated compared to wild-type tumors. In conclusion, the assessment of these mutations suggests that CRC patients from southeast Romania exhibit a mutation profile similar to other populations. These results could contribute to creating a better method of qualifying patients for molecularly targeted therapies and obtaining better screening strategies.

Effect of KRAS codon 12 or 13 mutations on survival with trifluridine/tipiracil in pretreated metastatic colorectal cancer: a meta-analysis.

BACKGROUND: KRAS gene mutations can predict prognosis and treatment response in patients with metastatic colorectal cancer (mCRC). METHODS: We undertook a meta-analysis of three randomized, placebo-controlled trials (RECOURSE, TERRA and J003) to investigate the impact of KRAS mutations in codons 12 or 13 on overall survival (OS) and progression-free survival in patients receiving trifluridine/tipiracil (FTD/TPI) for refractory mCRC. RESULTS: A total of 1375 patients were included, of whom 478 had a KRAS codon 12 mutation and 130 had a KRAS codon 13 mutation. In univariate analyses, the absence of a KRAS codon 12 mutation was found to significantly increase the OS benefit of FTD/TPI relative to placebo compared with the presence of the mutation {hazard ratio (HR), 0.62 [95% confidence interval (CI): 0.53-0.72] versus 0.86 (0.70-1.05), respectively; interaction P = 0.0206}. Multivariate analyses showed that taking confounding factors into account reduced the difference in treatment effect between the presence and the absence of KRAS codon 12 mutations, confirming that treatment benefit was maintained in patients with [HR, 0.73 (95% CI: 0.59-0.89)] and without [HR, 0.63 (95% CI: 0.54-0.74)] codon 12 mutations (interaction P = 0.2939). KRAS mutations in codon 13 did not reduce the OS benefit of FTD/TPI relative to placebo, and, furthermore, KRAS mutations at either codon 12 or codon 13 did not affect the progression-free survival benefit. CONCLUSIONS: Treatment with FTD/TPI produced a survival benefit, relative to placebo, regardless of KRAS codon 12 or 13 mutation status in patients with previously treated mCRC.

[Detection of epidermal growth factor receptor gene mutations in non-small cell lung cancers by real-time polymerase chain reaction using scorpion amplification refractory mutation system].

OBJECTIVE: To investigate mutations of EGFR gene in non-small cell lung cancers (NSCLC) using scorpions amplification refractory mutation system (Scorpions ARMS) is in comparing the detection sensitivity with that by PCR-direct sequencing method, and in addition to study the correlation between the mutations and the clinicopathological characteristics of the patients. METHODS: Tumor cells were collected by microdissection from paraffin embedded tumor specimens and adjacent normal lung tissues of 82 NSCLC patients. The genomic DNA was extracted. Mutations of EGFR gene (exons 18, 19, 20 and 21) were detected by PCR-direct sequencing and Scorpions ARMS methods respectively. RESULTS: Somatic mutations were identified involving the tyrosine kinase domain of the EGFR gene in 42 of 82 cases with a mutation detection rate of 51.2% by Scorpions ARMS assay. In-frame deletions of exon 19 occurred in 20 patients and point mutation occurred at codon 858, 861 (exon 21) in 18 and 1 patients respectively. Two patients had insertions mutations and 1 patient had point mutation occurring at codon 768 (exon 20). Among the 58 informative cases analyzed by PCR-direct sequencing, 25 mutations (detection rate of 30.5%) were identified. In-frame deletions of exon 19 occurred in 13 patients and point mutation occurred at codon 858, 861 (exon 21) in 10 and 1 patients respectively. In addition, 1 patient had point mutation at codon 768 (exon 20). Overall, Scorpions ARMS assay was more sensitive in detecting mutations of EGFR than PCR-direct sequencing. CONCLUSIONS: A higher incidence of somatic mutations of EGFR gene was detected in NSCLC of Chinese patients. Mutations were more common in female, non-smoking patients with adenocarcinoma and bronchioloalveolar carcinoma histology. Scorpions ARMS method is quicker, more sensitive and accurate in detecting the EGFR gene mutations and should provide important therapeutic and prognostic information to the clinicians.

Anti-monocyte chemoattractant protein-1 gene therapy prevents dimethylnitrosamine-induced hepatic fibrosis in rats.

Monocyte chemoattractant protein-1 (MCP-1) has been implicated in the process of hepatic inflammation, recruiting monocytes and lymphocytes during liver injury. MCP-1 also activates directly hepatic stellate cells, which play a major role in hepatic fibrosis. However, it remains unclear whether blockage of MCP-1 signaling could prevent hepatic fibrosis in vivo. We evaluated a strategy for anti-MCP-1 gene therapy against hepatic fibrosis by transfecting an amino-terminal deletion mutant, lacking the amino-terminal codons 2 to 8 of the human MCP-1 gene and designated 7ND, into skeletal muscle in a rat experimental model of dimethylnitrosamine (DMN)-induced fibrosis. Anti-MCP-1 gene therapy decreased significantly the occurrence of DMN-induced hepatic fibrosis, evaluated by computed image analysis and by measurement of hydroxyproline contents of the liver, accompanied by a reduction in the expressions of alpha-smooth muscle actin. This treatment also caused a significant decrease in hepatic tissue levels of interleukin (IL)-12 (Th1 cytokine) and an increase in those of IL-10 (Th2 cytokine), indicating a change in the Th1/Th2 cytokine balance in the liver. In conclusion, blockade of MCP-1 after intramuscular transfer of the 7ND gene suppressed hepatic fibrosis, and this strategy may be a useful and feasible gene therapy against hepatic fibrosis.