• 제목/요약/키워드: direct sequencing

검색결과 307건 처리시간 0.027초

Lack of Mutations in Protein Tyrosine Kinase Domain Coding Exons 19 and 21 of the EGFR Gene in Oral Squamous Cell Carcinomas

  • Mehta, Dhaval Tushar;Annamalai, Thangavelu;Ramanathan, Arvind
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제15권11호
    • /
    • pp.4623-4627
    • /
    • 2014
  • Background: The epidermal growth factor receptor (EGFR) plays a vital role in the activation and inactivation of receptor tyrosine kinases. Mutations in exons 19 and 21 of EGFR are commonly found to be associated with non small cell lung carcinoma and triple negative breast cancer, enhancing sensitivity to EGFR targeting chemotherapeutic agents. Since amplification and prolonged activation of EGFR molecules have been identified in oral squamous cell carcinomas (OSCC), we investigated whether OSCCs carried mutations in exons 19 and 21 of EGFR to their incidence. Materials and Methods: Tumor chromosomal DNA isolated from forty surgically excised oral squamous cell carcinoma tissues was subjected to PCR amplification with intronic primers flanking exons 19 and 21 of the EGFR gene. The PCR amplicons were subsequently subjected to direct sequencing to elucidate the mutation status. Results: Data analysis of the EGFR exon 19 and 21 coding sequences did not show any mutations in the forty OSCC samples that were analyzed. Conclusions: To the best of our knowledge, this is the first study to have investigated the genetic status of exons 19 and 21 of EGFR in Indian OSCCs and identified that mutation in EGFR exon 19 and 21 may not contribute towards their genesis. The absence of mutations also indicates that oral cancerous lesions may not be as sensitive as other cancers to chemotherapeutic agents targeting EGFR.

Hepatitis B Virus Genetic Variation and TP53 R249S Mutation in Patients with Hepatocellular Carcinoma in Thailand

  • Thongbai, Chureeporn;Sa-nguanmoo, Pattaratida;Kranokpiruk, Pavanrat;Poovorawan, Kittiyod;Poovorawan, Yong;Tangkijvanich, Pisit
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제14권6호
    • /
    • pp.3555-3559
    • /
    • 2013
  • Chronic hepatitis B virus (HBV) infection and dietary exposure to aflatoxin B1 (AFB1) are major risk factors for hepatocellular carcinoma (HCC). The aim of this study was to evaluate the role of HBV genetic variation and the R249S mutation of the p53 gene, a marker of AFB1-induced HCC, in Thai patients chronically infected with HBV. Sixty-five patients with and 89 patients without HCC were included. Viral mutations and R249S mutation were characterized by direct sequencing and restriction fragment length polymorphism (RFLP) in serum samples, respectively. The prevalences of T1753C/A/G and A1762T/G1764A mutations in the basal core promotor (BCP) region were significantly higher in the HCC group compared to the non-HCC group. R249S mutation was detected in 6.2% and 3.4% of the HCC and non-HCC groups, respectively, which was not significantly different. By multiple logistic regression analysis, the presence of A1762T/G1764A mutations was independently associated with the risk of HCC in Thai patients.

Relationship between Epidermal Growth Factor Receptor Gene Mutations and Clinicopathological Features in Patients with Non-Small Cell Lung Cancer in Western Turkey

  • Unal, Olcun Umit;Oztop, Ilhan;Calibasi, Gizem;Baskin, Yasemin;Koca, Dogan;Demir, Necla;Akman, Tulay;Ellidokuz, Hulya;Yilmaz, Ahmet Ugur
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제14권6호
    • /
    • pp.3705-3709
    • /
    • 2013
  • Background: To investigate epidermal growth factor receptor (EGFR) gene mutations in patients with non-small cell lung cancer (NSCLC) and to analyze any relationship with clinicopathological features and prognosis. Materials and Methods: EGFR gene exons 18-21 in 48 specimens of paraffin-embedded tumor tissue from NSCLC patients were amplified by PCR, followed by direct sequencing and analysis of links to clinicopathological features and prognosis. Results: EGFR mutations were detected in 18 of 48 (42.6%) patients with NSCLC. There were 9 cases of mutations in exon 20, 7 in exon 19 and 2 in exon 21. Mutations were more frequently observed in women (5/7 pts, 71.4%) than in men (13/41 pts, 31.7%) (p=0.086) and in non-smokers (5/5 pts, 100%) than smokers (13/43 pts, 30.2%). There was negative correlation of EGFR mutations with smoking status (p=0.005). EGFR mutations were more frequently observed with adenocarcinoma histology (13/32 pts, 40.6%) than in other types (5/16 pts, 31.3%) (p=0.527). The patients with EGFR mutations had better survival than those with wild-type EGFR (p=0.08). There was no association of EGFR mutations with metastatic spread. Conclusions: EGFR mutations in NSCLC were here demonstrated more frequently in females, non-smokers and adenocarcinoma histology in the western region of Turkey. Patients with EGFR mutations have a better prognosis.

P53 Polymorphism at Codon 72 is Associated with Keratocystic Odontogenic Tumors in the Thai Population

  • Yanatatsaneejit, Pattamawadee;Boonsrang, Ajaree;Mutirangura, Apiwat;Patel, Vyomesh;Kitkumthorn, Nakarin
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제16권5호
    • /
    • pp.1997-2001
    • /
    • 2015
  • Objective: To clarify the association between the p53 polymorphism at codon 72 and susceptibility to the sporadic keratocystic odontogenic tumor (KCOT). Design: One hundred KCOTs and 160 match-group healthy controls were genotyped to ascertain the frequency of the p53 codon 72 polymorphism using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), confirmed by direct sequencing. Results: The frequencies of the Pro/Pro, Arg/Pro, and Arg/Arg genotypes were 23.8%, 49.4%, and 26.9%, respectively, in the controls, while the KCOT cohort demonstrated 43.0%, 39.0%, and 18.0%, respectively. Further analysis suggested that p53 Pro could be a KCOT-susceptible allele (OR (95%CI)=1.77 (1.22 to 2.59), p=0.0024), with a sex-adjusted OR (95%CI) of 1.71 (1.17-2.50), p=0.0046. Moreover, the results indicated that p53 codon 72 Pro homozygous was associated with a two-fold risk of developing KCOT (adjusted OR (95%CI) =2.17(1.23-3.84), p=0.0062). Conclusions: The C/C genotype of P53 gene codon 72 increases the risk of developing sporadic KCOT and may be a useful tool for screening and diagnostic purposes.

VHL Gene Mutation Analysis of a Chinese Family with Non-Syndromic Pheochromocytomas and Patients with Apparently Sporadic Pheochromocytoma

  • Zhang, Bin;Qian, Jing;Chang, De-Hui;Wang, Yang-Min;Zhou, Da-Hai;Qiao, Gou-Mei
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제16권5호
    • /
    • pp.1977-1980
    • /
    • 2015
  • Objective: The Von Hippel-Lindau syndrome (VHLD), an inherited neoplastic syndrome predisposing to central nervous system hemangioblastoma (CNS), pheochromocytoma (PCC), renal cell carcinoma(RCC), retinal hemangioma (RA) and renal cysts, is caused by mutations or deletions of the VHL tumor-suppressor gene. To assess VHL genotype-phenotype correlations with function of pVHL a gene mutation analysis of members in a Chinese family with non-syndromic PCCs and individuals with apparently sporadic pheochromocytoma (ASP) was performed. Materials and Methods: DNA samples of 20 members from the Chinese family with non-syndromic PCCs and 41 patients with ASP were analyzed by polymerase chain reaction and direct sequencing, confirmed by Taqman probe. Results: Three novel mutations (H125P, 623(^TTTGTtG) and R120T) were identified in the Chinese family and in 3 among 41 ASP patients. The mutations were all located in exon 2 of VHL gene encoding ${\beta}$-domain of pVHL. The tumor type in H125P carriers and R120T carriers was VHL type 2C. And 623(^TTTGTtG) carriers presented VHL type 2B or type 2C. Conclusions: VHL gene abnormalities were identified in the Chinese family with non-syndromic PCCs and patients with APS, resulting in dysfunction of pVHL. H125P and R120T could be associated with VHL type 2C, while 623(^TTTGTtG) might be linked with VHL type 2B or type 2C. Not only is the genetic analysis helpful for early diagnosis and treatment of patients with VHLD, it is also benefitial for research intoVHLD pathogenesis.

Prevalence of IDH1/2 Mutations in Different Subtypes of Glioma in the North-East Population of Morocco

  • Senhaji, Nadia;Louati, Sara;Chbani, Laila;Bardai, Sanae El;Mikou, Karima;MAAROUFI, Mustafa;Benzagmout, Mohammed;Faiz, Mohammed Chaoui El;Marie, Yannick;Mokhtari, Karima;Idbaih, Ahmed;Amarti, Afaf;Bennis, Sanae
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제17권5호
    • /
    • pp.2649-2653
    • /
    • 2016
  • Background: Genetic alterations in gliomas have increasing importance for classification purposes. Thus, we are especially interested in studying IDH mutations which may feature potential roles in diagnosis, prognosis and response to treatment. Our aim was to investigate IDH mutations in diffuse glioma patients diagnosed in university hospital centre of Fez in Morocco. Materials and Methods: IDH1 codon 132 and IDH2 codon 172 were direct-sequenced in 117 diffuse glioma samples diagnosed and treated in University Hospital Hassan II between 2010 and 2014. Results: The R132H IDH1 mutation was identified in 43/117 tumor samples and R172K IDH2 mutation was detected in only one anaplastic oligodendroglioma. IDH mutations were observed in 63.2% of astrocytomas, 73.3% of diffuse oligodendrogliomas and 12.90% of glioblastomas. Conclusions: Our results confirmed other studies published earlier for other populations with some small discrepancies.

Effects of a Novel p.A41P Mutation in the Swine Myogenic factor 5 (MYF5) Gene on Protein Stabilizing, Muscle Fiber Characteristics and Meat Quality

  • Ryu, Youn-Chul;Lee, Eun-A;Chai, Han-Ha;Park, Jong-Eun;Kim, Jun-Mo
    • 한국축산식품학회지
    • /
    • 제38권4호
    • /
    • pp.711-717
    • /
    • 2018
  • Myogenic factor 5 (MYF5) plays an important role in regulating skeletal muscle fiber characteristics, consequently affecting meat production and quality. We identified a novel p.A41P mutation in exon1 of the porcine MYF5 gene by direct sequencing. The mutation was predicted to be destabilizing in protein structure based on the resultant amino acid substitution. We estimated the significant substitution effect of p.A41P on the energy stabilization of Myf5 protein structure. Then, we demonstrated that the mutation in Yorkshire population significantly affected muscle fiber type I composition (p<0.05), loin-eye area of lean meat content (p<0.05) and filter-fluid uptake of meat quality (p<0.01). Furthermore, dominant effects significantly influenced total muscle fiber number (p<0.05). This study suggests that the novel p.A41P mutation in porcine MYF5 may be a valuable genetic marker to affect the muscle fiber characteristics and consequently improve meat production quality and quantity.

Identification of a Novel Single Nucleotide Polymorphism in Porcine Beta-Defensin-1 Gene

  • Pruthviraj, D.R.;Usha, A.P.;Venkatachalapathy, R.T.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • 제29권3호
    • /
    • pp.315-320
    • /
    • 2016
  • Porcine beta-defensin-1 (PBD-1) gene plays an important role in the innate immunity of pigs. The peptide encoded by this gene is an antimicrobial peptide that has direct activity against a wide range of microbes. This peptide is involved in the co-creation of an antimicrobial barrier in the oral cavity of pigs. The objective of the present study was to detect polymorphisms, if any, in exon-1 and exon-2 regions of PBD-1 gene in Large White Yorkshire (LWY) and native Ankamali pigs of Kerala, India. Blood samples were collected from 100 pigs and genomic DNA was isolated using phenol chloroform method. The quantity of DNA was assessed in a spectrophotometer and quality by gel electrophoresis. Exon-1 and exon-2 regions of PBD-1 gene were amplified by polymerase chain reaction (PCR) and the products were subjected to single strand conformation polymorphism (SSCP) analysis. Subsequent silver staining of the polyacrylamide gels revealed three unique SSCP banding patterns in each of the two exons. The presence of single nucleotide polymorphisms (SNPs) was confirmed by nucleotide sequencing of the PCR products. A novel SNP was found in the 5'-UTR region of exon-1 and a SNP was detected in the mature peptide coding region of exon-2. In exon-1, the pooled population frequencies of GG, GT, and TT genotypes were 0.67, 0.30, and 0.03, respectively. GG genotype was predominant in both the breeds whereas TT genotype was not detected in LWY breed. Similarly, in exon-2, the pooled population frequencies of AA, AG, and GG genotypes were 0.50, 0.27, and 0.23, respectively. AA genotype was predominant in LWY pigs whereas GG genotype was predominant in native pigs. These results suggest that there exists a considerable genetic variation at PBD-1 locus and further association studies may help in development of a PCR based genotyping test to select pigs with better immunity.

Detection of the BCR/abl Gene Rearrangement by Reverse Transcriptase Based Polymerase Chain Reaction

  • Lee, Kyung-Ok;Park, Young-Suk;Kim, Yong-Woo;Han, Jung-A;Kim, Yoon-Jung
    • BMB Reports
    • /
    • 제29권3호
    • /
    • pp.241-247
    • /
    • 1996
  • The Philadelphia (Ph) chromosome is the single most intensively studied chromosome alteration characterizing a human malignancy. The specific genetic alteration of chronic myelogenous leukemia (CML) is the formation of the BCR/abl fusion gene in leukemic cells. The presence of the BCR/abl gene has important diagnostic and prognostic implications in CML. The detection of BCR/abl transcripts by reverse transcriptase based polymerase chain reaction (RT-PCR) was investigated in patients with CML in whom the Ph chromosome abnormality was documented by cytogenetic analysis. In a total of 68 CML patient cases, the Ph chromosome was found in 53 cases (77.9%) by cytogenetic analysis. On the other hand, sixty two cases (91.2%) were detected to have BCR/abl gene rearrangement Of these, b3a2 was 44 cases (64.7%) and b2a2 was 17 cases (25,0%). There was one case with both b3a2 and b2a2 (1.5%). Of the fifteen cases of Ph chromosome negative by cytogenetic anlaysis, the BCR/abl gene was observed in nine cases, The results of BCR/abl fusion gene confirmed by the direct sequencing method correlated well with PCR analysis, The amplified PCR products were detected by $1{\times}10^{-5}$ dilutions. In conclusion, PCR technique is sensitive, rapid and relatively simple for a laboratory test in detecting the BCR/abl fusion gene with CML regardless of the result of cytogenetic analysis.

  • PDF

Spirometra decipiens (Cestoda: Diphyllobothriidae) Collected in A Heavily Infected Stray Cat from the Republic of Korea

  • Jeon, Hyeong-Kyu;Park, Hansol;Lee, Dongmin;Choe, Seongjun;Eom, Keeseon S.
    • Parasites, Hosts and Diseases
    • /
    • 제56권1호
    • /
    • pp.87-91
    • /
    • 2018
  • Morphological and molecular characteristics of spirometrid tapeworms, Spirometra decipiens, were studied, which were recovered from a heavily infected stray cat road-killed in Eumseong-gun, Chungcheongbuk-do (Province), the Republic of Korea (=Korea). A total of 134 scolices and many broken immature and mature proglottids of Spirometra tapeworms were collected from the small intestine of the cat. Morphological observations were based on 116 specimens. The scolex was 22.8-32.6 mm (27.4 mm in average) in length and small spoon-shape with 2 distinct bothria. The uterus was coiled 3-4 times, the end of the uterus was ball-shaped, and the vaginal aperture shaped as a crescent moon was closer to the cirrus aperture than to the uterine aperture. PCR amplification and direct sequencing of the cox1 target fragment (377 bp in length and corresponding to positions 769-1,146 bp of the cox1 gene) were performed using total genomic DNA extracted from 134 specimens. The cox1 sequences (377 bp) of the specimens showed 99.0% similarity to the reference sequence of S. decipiens and 89.3% similarity to the reference sequence of S. erinaceieuropaei. In the present study, we report a stray cat heavily infected with S. decipiens identified by mitochondrial cox1 sequence analysis and morphological examinations of the adult worms.