RESUMEN
The aim of the present study was to investigate mutation status of the c-Kit gene (KIT) and PDGFRA in patients with a gastrointestinal stromal tumor (GIST). In total, 93 patients with a GIST were included in the study, in which polymerase chain reaction amplification and gene sequencing were used to detect the sequences of exons 9, 11, 13 and 17 in KIT and exons 12 and 18 in PDGFRA. KIT mutations were detected in 64 cases (68.82%), of which exon 11 mutations were detected in 56 cases (60.22%), exon 13 mutations were detected in three cases (3.23%) and one case (1.08%) was shown to have a mutation in exon 17. The most common mutation in exon 11 was a deletion, which accounted for 55.36% (31/56) of the cases, followed by a point mutation observed in 26.79% (15/56) of the cases, while an insertion (tandem repeats) was identified in 14.29% (8/56) of the cases, and 3.57% (2/56) of the exon 11 mutations were deletions associated with a point mutation. The majority of the mutations were heterozygous, with only a few homozygous mutations. Mutational analysis revealed the mutations to be more concentrated in the classic hot zone at the 5'-end, followed by the tandem repeat frame at the 3'-end. In four cases, a mutation was detected in exon 18 of PDGFRA, of which one was associated with a mutation in KIT. The remaining three cases (10.34%, 3/29) were not associated with mutations in KIT and accounted for 37.5% (3/8) of the CD117-negative GIST cases. Therefore, the majority of the GIST cases were characterized by mutations in KIT or PDGFRA, which were directly associated with the disease. Pairs of different mutations in the same exon of KIT, or KIT mutations coupled with pairs of mutations in PDGFRA, were detected in a small number of patients. Imatinib is a small molecule tyrosine kinase inhibitor and is the first line targeted treatment for GIST, resulting in markedly improved survival rates. Thus, gene mutation genotyping may provide inspiration and guidance for imatinib-based targeted cancer therapy.
RESUMEN
This study aimed to investigate the association of the mRNA expression of the echinoderm microtubule-associated protein-like 4 (EML4)-anaplastic lymphoma kinase (ALK) fusion gene with that of thymidylate synthase (TYMS) in non-small cell lung cancer (NSCLC) tissues. Quantitative polymerase chain reaction was used to detect the expression of EML4-ALK fusion gene and TYMS mRNA in 257 cases of NSCLC. The positive rate of EML4-ALK fusion gene was 4.28% in the NSCLC tissues (11/257), and was higher in nonsmokers than in smokers (P<0.05); TYMS mRNA expression was detected in 63.42% (163/257) of cases. An association of the EML4-ALK fusion gene with TYMS expression was detected; a low expression level of TYMS mRNA was observed more frequently when the EML4-ALK fusion gene was present than when it was not detected (P<0.05). In conclusion, patients positive for the EML4-ALK fusion gene in NSCLC tissues are likely to have a low expression level of TYMS, and may benefit from the first-line chemotherapy drug pemetrexed.
RESUMEN
The present study aimed to investigate the association between epidermal growth factor receptor (EGFR) gene mutations and excision repair cross-complementing protein 1 (ERCC1) and ribonucleotide reductase subunit M1 (RRM1) mRNA expression in non-small cell lung cancer (NSCLC) tissue. The quantitative polymerase chain reaction was used to detect EGFR mutations, and ERCC1 and RRM1 mRNA expression in 257 cases of NSCLC. In the NSCLC samples the EGFR mutation rate was 49.03% (126/257). The rate was higher in females and non-smoking patients (P<0.05). High expression of ERCC1 mRNA was observed in 47.47% of the samples (122/257), while a high RRM1 mRNA expression was observed in 61.87% of the samples (159/257). In comparison with patients with NSCLC without EGFR mutations, patients with EGFR mutations had significantly lower levels of ERCC1 mRNA expression (P<0.05); however, EGFR mutations and expression levels of RRM1 mRNA were not correlated in NSCLC tissues (P>0.05). In addition, ERCC1 mRNA expression was not correlated with the expression levels of RRM1 mRNA (P>0.05). In conclusion, patients with NSCLC with EGFR mutations tend to have a low expression of ERCC1 mRNA and may potentially benefit from platinum-based chemotherapy.
