• Radiation Oncology Journal
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• v.19 no.2
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• pp.107-112
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• 2001

Purpose : To determine the prognostic significance of p53 mutations in advanced supraglottic cancer patients. Material and Methods : Twenty-six patients with pertinent tissue materials among 60 patients diagnosed as advanced supraglottic cancer in Kyung Hee university hospital and received total or partial laryngectomy followed by radiation therapy were enrolled. Immunohistochemical staining using DO7 monoclonal antibody was peformed. Tumor specimens were analyzed for p53 mutations in exons 5 through 8 by using PCR-SSCP analysis followed by DNA sequencing of all variants. Results : p53 mutations were present in 8 cases among 26 patiets. Mutations within exon 5 were 3 cases, exon 6 were 4 cases, and exon 7 was 1 case. Mean survival time was 70.2 months in patients without mutations, 61.3 months with mutations but there was no statistically significant differences (p=0.596). Mutations were $25\%$ in stage III and $36\%$ in stage IV but there was no statistically significant differences (p=0.563). Mutations were $25\%$ in lymph node negative group and $42\%$ in lymph node positive group but there was no statistically significant differences (p=0.437). Conclusion : The presence of p53 mutation detected by PCR-SSCP is not associated with survival, stage and lymph node status.

• Journal of the Korean Chemical Society
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• v.47 no.5
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• pp.460-465
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• 2003

Structural alteration of p53 and overexpression of p53 protein are the most common genetic abnormalities in various kinds of human cancer. Mutations in the p53 tumor-suppressor gene are usually associated with an advanced development of colorectal cancer characterized by the transition from the adenoma to carcinoma stage. Mutations in exons 5-8 of the p53 gene were analyzed by the polymerase chain reaction-single strand conformation polymorphism(PCR-SSCP) and denaturing high performance liquid chromatography(DHPLC). SSCP analysis detected 7 mutations(C13109>T) in 50 colorectal cancer samples(14%) at exon 5, and DHPLC analysis detected 7 mutations (C13109>T) and 2 mutation(C13202>A, C13204>G) in 50 colorectal cancer samples(18%) at exon 5. All of 9 mutations were proved by sequencing analysis. We conclude that DHPLC is a highly sensitive and specific method for p53 gene mutations.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.26 no.1
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• pp.45-52
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• 2000

Nowadays, there are a lot of evidence that mutation of the p53 tumor suppressor gene is one of the most common genetic abnormalities in neoplastic progression. In this study, we analyzed 20 specimens of oral tumors(squamous cell carcinoma 14 cases, ameloblastoma 3 cases, adenoid cystic carcinoma 2 cases, malignant schwannoma 1 case)using polymerase chain reaction and direct sequencing which used an automated DNA sequencer and software for detection of mutations. Polymerase chain reactions were performed with 4 sets of primers encompassing exon 5, 6, 7, 8, and direct sequencing method was employed. The results were as followings. 1. We detected 10 point mutations out of 20 specimens (50%). 2. The genetic alterations included 7 mis-sense mutations resulting in single amino acid subtitutions, 2 silent mutations, 1 non-sense mutations encoding a stop codon. 3. Mutations were mostly in exon 7(7 out of 10 mutations, 70%) and involved codons 225, 234, 235, 236, 238, 247. 4. Therse were 4 cases of $T{\rightarrow}A$ transversion, 2 cases of $C{\rightarrow}A$ transversion, $A{\rightarrow}G$ transition, 1 case of $C{\rightarrow}G$, $T{\rightarrow}G$ transversion respectively. 5. We could find out point mutations more conveniently using PCR - Automated Direct Sequencing method.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.9
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• pp.4477-4479
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• 2012

Background: The high incidence and relatively good prognosis of breast cancer has made it the most prevalent cancer in the world today. A large number of distinct mutations and polymorphisms in the p53 gene have been reported worldwide, but there is no report regarding the role of this inherited susceptibility gene in breast cancer risk among the Bengalee Hindu Caste females of West Bengal, India. Aim of the Study: We investigated the distribution and the nature of p53 gene mutations and polymorphisms in exons 5-7 in a cohort of 110 Bengalee Hindu breast cancer patients and 127 age, sex and caste matched controls by direct sequencing. Results: We did not observe any mutations and polymorphisms in our studied individuals. Conclusion: We therefore conclude that mutations in exons 5-7 of p53 gene are rare causes of breast cancer among Bengalee Hindu caste females, and therefore of little help for genetic counseling and diagnostic purposes.

• The Korean Journal of Zoology
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• v.39 no.3
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• pp.231-238
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• 1996

Several types of human lung and pancreatic carcinoma cell lines were cultured and their chromosomal DNAs were extracted. These DNAs were then partially amplified by PCR (Polymerase Chain Reaction) and sequenced to analyze the types and frequency of mutations, and their possible relation in the oncogene, K-ras and suppressor gene, p53. Regardless of the cell line origin, 81% were found to possess at least one mutation. Among the cell lines analyzed, 54.5% of the mutations were found in either K-ras or p53. Except for one nonsense mutation, all mutations were missense with either base insertions or substitutions. Furthermore, besides the p53 codons Known to be mutated simultaneously with' ras to enhance tumor growth, p53 164-165 and 248 were found to be mutated simultaneously with K-ms. Regardless of the site of p53 mutation, all K-ras mutations found in these cases occurred at exon 1, codon 12.

• Journal of Gastric Cancer
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• v.6 no.4
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• pp.214-220
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• 2006

Purpose: p53 is one of the most commonly mutated genes in human tumors. The aim of this study was to analyze p53 mutation in gastric cancer and its correlations with the clinicopathologic variables to clarify the usefulness of p53 mutation as a prognostic factor. Materials and Methods: Specimens from 331 patients with gastric cancer who underwent a gastrectomy between March 1999 and April 2001 at the Kyungpook National University Hospital were used. p53 gene mutations were assessed by using a polymerase chain-reaction single-strand conformation polymorphism (PCR-SSCP) analysis. The correlations between p53 gene mutation and clinocopathologic parameters were analyzed. Results: p53 mutations were found in 66 (19.9%) tumors. Among those 66 cases, mutations were seen in 23 tumors at axon 5, in 8 at exon 6, in 21 at exon 7, and in 17 at exon 8. Two mutations were shown in 3 tumors. Thiriy-six (23.1%) of 156 intestinal-type tumors and 19 (13.1%) of 145 diffuse-type tumors showed p53 gene mutation (P=0.007). The frequency of p53 gene mutation didn't show any significant differences according to age, sex, stage, location, or gross type. Exon 5 mutations showed more frequently in intestinal-type tumors than in diffuse-type tumors (9.7% vs. 2.8%, P=0.024), and p53 mutation were more frequent in lymph nodes metastasis group than lymph nodes non-metastasis group with statistical significance (25.0% vs 15.6%, P=0.034). The five-year survival rate showed no statistically significant difference with p53 mutation (P=0.704). Conclusion: p53 mutations assessed by PCR-SSCP had little value as a prognostic factor after gastrectomy in patients with gastric cancer.

• The Journal of the Korean bone and joint tumor society
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• v.6 no.4
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• pp.143-151
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• 2000

Purpose : The p53 tumor suppressor gene is one of the most frequently altered genes in human malignancies. We try to explore the implication of p53 alteration in Ewing's sarcoma. Materials and Methods : We analyzed 35 paraffin blocks to explore the deletion and sequence alterations of p53. Results : Quantitative PCR analysis showed that 2 tumors showed a homozygous deletion of the gene. Mutational analysis of exons 4 to 9 of p53 by PCR-SSCP revealed that 3 tumors carry sequence alterations in exons 5 or 8, and DNA sequencing analysis identified missense point mutations. Conclusion : Taken together, our data demonstrate that p53 is genetically altered in a small fraction of Ewing's sarcoma.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.13
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• pp.5211-5217
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• 2015

Background: We earlier used PCR-dHPLC for mutation analysis of BRCA1 and BRCA2. In this article we report application of targeted resequencing of 30 genes involved in hereditary cancers. Materials and Methods: A total of 91 patient samples were analysed using a panel of 30 genes in the Illumina HiScan SQ system. CLCBio was used for mapping reads to the reference sequences as well as for quality-based variant detection. All the deleterious mutations were then reconfirmed using Sanger sequencing. Kaplan Meier analysis was conducted to assess the effect of deleterious mutations on disease free and overall survival. Results: Seventy four of the 91 samples had been run earlier using the PCR-dHPLC and no deleterious mutations had been detected while 17 samples were tested for the first time. A total of 24 deleterious mutations were detected, 11 in BRCA1, 4 in BRCA2, 5 in p53, one each in RAD50, RAD52, ATM and TP53BP1. Some 19 deleterious mutations were seen in patients who had been tested earlier with PCR-dHPLC [19/74] and 5/17 in the samples tested for the first time, Together with our earlier detected 21 deleterious mutations in BRCA1 and BRCA2, we now had 45 mutations in 44 patients. BRCA1c.68_69delAG;p.Glu23ValfsX16 mutation was the most common, seen in 10/44 patients. Kaplan Meier survival analysis did not show any difference in disease free and overall survival in the patients with and without deleterious mutations. Conclusions: The NGS platform is more sensitive and cost effective in detecting mutations in genes involved in hereditary breast and/or ovarian cancers.

• Journal of the Korean Chemical Society
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• v.48 no.1
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• pp.33-38
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• 2004

Mutation of p53 tumor suppressor gene in HNSCC (head and neck squamous cell carcinoma) has been proposed high rate. We extracted genomic DNA from 50 head and neck cancer. The DNA was amplified by PCR at exon 5-8 in p53 tumor suppressor gene. We have compared single strand conformation polymorphism (SSCP) and denaturing high performance liquid chromatography (DHPLC) method for analysis of p53 somatic mutation. As a result, 16 deleted mutations (32%) were detected by SSCP analysis and 17 deleted mutations (34%) were detected by DHPLC analysis at exon 8. All of 17 mutations were proved by sequencing. We conclude that DHPLC is a fast and simple screening method rather than SSCP analysis.

• Environmental Mutagens and Carcinogens
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• v.18 no.1
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• pp.9-14
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• 1998

By far, the largest known preventable cause of cancer is cigarette smoking. The percentage of cancer deaths in Korea due to tobacco is still increasing. Smoking cigarette at an early age has become more common among women. Tobacco consumption is related causally to cancer to the lung, mouth, larynx, esophagus, bladder, kidney, uterine cervix, and pancreas. Recently, several studies demonstrated that there is very strong correlation between cigarette smoking and p53 mutations in lung cancer, head and neck cancer, and bladder cancer. The recent findings of cigarette smoking and cancer, p53 and bcl-2 mutations, adverse effects of smoking on the effects of radiotherapy, and benefits of quitting will be discussed.