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Results for “Gene mutation”

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At least 145 records · Page 8Linked to original sources

PubMed2001

Association of p53 gene mutation and telomerase activity in resectable non-small cell lung cancer.

PURPOSE: Mutation of the p53 gene and deregulation of telomerase may be essential for canceration in some malignant diseases. However, relationships between these occurrences have not yet been clarified. We examined the roles of p53 gene mutation and telomerase activity relative to the clinical and pathologic features of non-small cell lung carcinoma (NSCLC). METHODS: Frozen sections of 40 surgically resected NSCLC specimens were used. DNA extracted from fresh tumor specimens was analyzed with polymerase chain reaction (PCR), single-strand conformation polymorphism (SSCP) method, to screen alterations in the p53 gene. Exons showing aberrant band shifts on SSCP were reamplified, and the PCR products were directly sequenced. In addition, the telomerase activity of the same specimens was analyzed quantitatively with the fluorescence-based telomeric repeat amplification protocol assay, and the total product generated (TPG) method. Clinical and pathologic parameters were evaluated using a statistical analysis system. RESULTS: Mutations of the p53 gene relevant to an altered protein were confirmed in 19 of 40 specimens (47.5%). The TPG of 40 specimens was 75.24 +/- 15.55 (mean +/- SE). The TPG of the 19 specimens positive for p53 gene mutation was significantly higher than that of the 21 specimens negative for p53 gene mutation. Furthermore, the degree of cell differentiation was significantly correlated with both p53 gene mutation and high telomerase activity. CONCLUSIONS: p53 gene mutation and high telomerase activity cooperate to induce tumorigenesis and low-grade differentiation in NSCLC. Simultaneous occurrence of p53 gene mutation and high telomerase activity may be relevant to the grade of malignancy in NSCLC.

Aged↗

PubMed2002

[BRCA2 gene mutation detection in hereditary ovarian cancer tissues].

OBJECTIVE: The aim of this study was to detect the mutation of BRCA2 gene in hereditary ovarian cancer tissues to probe the clinical significance of it. METHODS: DNA was abstract from paraffin embedded tissues archived in pathology department. A pair of primer located on 11 exon was used to detect the 6174 delT mutation,BRCA2 gene mutation in 12 hereditary ovarian cancer patients and 15 sporadic ovarian cancer patients were screened by polymerase chain reaction-single strand conformation polymorphism analysis with DNA non- isotopic silver staining methods. RESULTS: Two of 12 hereditary ovarian cancer victims were found carrying mutation of BRCA2 gene. The mutation type was 6174del T in the 11 exon of BRCA2 gene. No mutation of BRCA2 gene on this site was found in 15 sporadic ovarian cancer patients. CONCLUSION: BRCA2 gene mutation was closely associated with the carcinogenesis and development of hereditary ovarian cancer, but had no relationship with sporadic ovarian cancer.

Female↗

PubMed2005

A novel nonsense mutation in the SCN5A gene leads to Brugada syndrome and a silent gene mutation carrier state.

BACKGROUND: Brugada syndrome (BS) is an electrical cardiac disorder with a right bundle branch block and ST segment elevation in leads V1 to V3 on surface electrocardiograms (ECGs), and is a syndrome that may lead to sudden cardiac death. PURPOSE: The aim of the present study was to screen for mutations in the SCN5A gene in a family with BS, and to characterize the consequences of the mutation on channel function. RESULTS: A heterozygous nonsense SCN5A mutation (W822X) was identified in the index patient. The mutation was confirmed in the patient's asymptomatic 16-year-old brother and 48-year-old father. The mutation was absent in the index patient's sister and mother. The ECG of the index patient showed a BS type 2 ECG phenotype, which converted into a type 1 ECG phenotype in the presence of flecainide. The ECG of the patient's brother was not typical for BS, but ajmaline treatment unmasked a type 1 ECG phenotype. The ECG of the asymptomatic father was normal at baseline and in the presence of ajmaline. No Na+ currents could be measured in tsA201 cells transfected with W822X mutant channels. Heterozygote expression showed a nearly 50% reduction in Na+ current amplitude with no significant alterations of biophysical properties, indicating a loss of functional Na+ channels, obviously without any dominant-negative activity on wild type channels. CONCLUSIONS: The haploinsufficiency of the Nav1.5 protein is the plausible explanation for the clinical BS phenotype in this family. Because the heterozygous W822X mutation theoretically leads to channel expression at one-half of the normal level, the authors suggest that a modifier gene may influence or rescue the phenotype in the asymptomatic family members.

Adolescent↗

PubMed2002

Relative high frequency of the c.255delA parkin gene mutation in Spanish patients with autosomal recessive parkinsonism.

BACKGROUND: Autosomal recessive juvenile parkinsonism is a neurodegenerative disorder associated with mutations in the parkin gene. OBJECTIVES: To search for the presence of parkin gene mutations in Spanish patients with Parkinson's disease (PD) and characterise the phenotype associated with these mutations. METHODS: Thirty seven PD patients with either early onset or autosomal recessive pattern of inheritance were selected for genetic study. RESULTS: Mutations were identified in seven index patients (19%). Homozygous mutations were detected in six patients and a heterozygous mutation in one. The age at onset was lower in patients with mutations than in patients without mutations. Dystonia at onset was present in two patients with parkin gene mutations. The disease began in two patients with postural tremor in the upper limbs mimicking essential tremor. Four patients exhibited a long term response to dopamine agonists. The c.255delA mutation was identified in four unrelated families. This is a frameshift mutation leading to protein truncation. CONCLUSIONS: Parkin gene mutations are present in Spanish patients with early onset and/or an autosomal recessive parkinsonism. The c.255delA is the most frequent mutation found, suggesting a relative high prevalence in the Spanish population.

Adult↗

PubMed2004

Predictive factors for pancreatic cancer in patients with chronic pancreatitis in association with K-ras gene mutation.

BACKGROUND AND STUDY AIMS: Chronic pancreatitis is considered to be a predisposing factor for pancreatic ductal adenocarcinoma (PAC). The purpose of this study was to examine the prognostic value of a finding of mutated (K- ras) gene in predicting the development of PAC in patients with chronic pancreatitis. PATIENTS AND METHODS: The pancreatic duct brushings of 146 patients with chronic pancreatitis were examined in order to identify K- ras gene mutations. A total of 112 patients were followed up (median duration 42 months) using clinical evaluation, serum CA19 - 9 levels, and imaging studies. RESULTS: One or more K- ras mutations were found in 57 of the 146 patients with chronic pancreatitis (39 %). Patients harboring K- ras mutations had a higher incidence of persistent alcohol consumption ( P = 0.041) and of prior rupture of the main pancreatic duct ( P = 0.040). A finding of nuclear atypia in brushing cytology was also more common in patients with K- ras mutation ( P = 0.048). Out of the 112 patients who were followed up, PAC occurred in four of the 44 patients who had a K- ras mutation, but in none of the 68 patients with the wild genotype ( P = 0.022). PAC occurred in three of the 25 patients who did not have pancreatic calcifications ( P = 0.034) and in four of the 54 patients who had demonstrated exocrine insufficiency, but in none of the 58 patients with preserved exocrine function ( P = 0.051). Using stepwise logistic regression, the absence of calcifications, the presence of exocrine insufficiency, and the presence of K- ras mutation were identified as independent predictive factors for cancer development in all patients with chronic pancreatitis. CONCLUSIONS: K- ras gene mutations occur in chronic pancreatitis and are associated with evolution towards PAC. The absence of pancreatic calcifications and the presence of exocrine insufficiency were identified as additional predictive factors for the development of PAC.

Alcohol Drinking↗

PubMed2006

Male infertility and androgen receptor gene mutations: clinical features and identification of seven novel mutations.

OBJECTIVE: Androgens and a functioning androgen receptor (AR) are essential for development and maintenance of the male phenotype and spermatogenesis. Consistent with this, mutations in the AR gene cause a variety of defects related to androgen insensitivity, ranging from complete feminization to phenotypic males with infertility. The aim of his study was to analyse the prevalence of AR gene mutations in male infertility and to clarify the genotype-phenotype relation. DESIGN: Males with infertility were recruited consecutively at the Centre for Male Gamete Cryopreservation at the University of Padova from January 1996 to January 2005. PATIENTS: One thousand five hundred and seventeen men with < 10 million sperm/ml and 310 age-matched normozoospermic controls. METHODS: Screening for AR gene mutation was done by DHPLC and sequencing, and reproductive hormone concentrations were measured. RESULTS: We found 20 mutations in 26 of 1517 patients (1.7%) and no mutations in controls. A high number of mutations localized in exon 1 of the AR gene coding for the transactivation domain of the protein. Of 20 mutations, 7 represent novel mutations. With respect to men without AR mutations, subjects with AR mutations have lower ejaculate volume, higher testosterone levels, higher oestradiol levels, and higher androgen sensitivity index. However, the ranges for these variables were highly overlapping between men with and without AR gene mutations. Also clinical manifestations of AR mutations are not unique and 22 men had only spermatogenic impairment. CONCLUSIONS: AR gene mutations are quite frequent in unselected infertile men but no specific hormonal or clinical data could be used to preselect patients at risk of mutations.

Adult↗

PubMed1993

p53 gene mutations in gastric adenomas.

p53 gene alterations in ten gastric adenomas and one carcinoma arising in an adenoma were analyzed by deoxynucleotide sequencing. Three (30%) of the ten gastric adenomas had p53 gene mutations, one adenoma showing a frameshift mutation and two others showing silent mutations. In addition, two missense mutations occurred in the carcinoma arising in an adenoma. Histologically, the adenomas containing silent mutations revealed moderate dysplasia. Immunoreactivity to p53 protein was also examined in 61 gastric adenomas, 19 carcinomas arising in adenomas and 48 early well-differentiated adenocarcinomas of the stomach (these included the tumors analyzed by deoxynucleotide sequencing). No staining for p53 was seen in the pure adenomas, but positive immunoreactivity was observed in 27% of the adenocarcinomas and 10.5% of the carcinomas arising in adenomas. These results suggest that p53 gene mutation is an early event in gastric carcinogenesis and missense mutation may play a crucial role in the conversion from adenoma to adenocarcinoma.

Adenoma↗

PubMed1992

Frequent association of p53 gene mutation in invasive bladder cancer.

Structural alterations of the p53 gene were investigated to elucidate the molecular biological difference between superficial and invasive bladder cancer by polymerase chain reaction single-strand conformation polymorphism analysis. In 25 bladder cancers obtained from 23 patients, p53 gene mutations were investigated in exon regions 4 to 11. Twenty-four were transitional cell carcinomas, and the remaining one was a squamous cell carcinoma. Only one of 13 superficial bladder cancers, including pTis, pTa, and pT1, was found to have p53 gene mutation. However, of 12 invasive bladder cancers with pT2, pT3, and pT4, six primary carcinomas, including a squamous cell carcinoma and one metastatic carcinoma, were found to have p53 gene mutations. The number of cancers examined in Grades 1, 2, and 3 was three, seven, and 15, respectively. p53 gene mutation was not found in any of the ten cancers with Grades 1 and 2, while eight of 15 bladder cancers with Grade 3 were found to have p53 gene mutation. The results indicated that the incidence of p53 gene mutations appeared to be much higher in invasive-type and high-grade bladder cancers than in superficial and low-grade ones. Our results are compatible with the recently published results by Sidransky et al. [Science (Washington DC), 252: 706-709, 1991] showing that p53 gene mutations were frequently found in invasive bladder cancers by sequence analysis on polymerase chain reaction amplified products corresponding to exons 5 to 9. Our results are also compatible with previously reported results by Olumi et al. (Cancer Res., 50: 7081-7083, 1990) showing that the loss of chromosome 17p, revealed by analysis with restriction fragment length polymorphism, was frequent in high-grade bladder cancers. In this study, p53 gene mutations were often found in exon 4 as well as in other exons. Therefore, this region should also be examined for screening of mutations of this gene in bladder cancer. There appeared to be no consistent mutation sites in exons 4 to 11 of the p53 gene and no specific patterns of the mutation in bladder cancer.

Base Sequence↗

PubMed1996

Reduced messenger RNA expression level of p21 CIP1 in human colorectal carcinoma tissues and its association with p53 gene mutation.

p21 Cip1 was first isolated as one of the cyclin-dependent kinase (Cdk) interacting proteins induced by wild-type p53 gene product, and it appears to play an essential regulatory role in the control of cell proliferation as a potent, tight-binding inhibitor of cyclin-Cdk complex that blocks the G1/S transition of the cell cycle. We have now examined the p21 Cip1 mRNA expression levels in 16 surgically excised human colorectal tumor and non-tumor tissues by Northern-blot analysis with reference to the identification of p53 gene mutations. p53 gene mutations were detected in 6 tumor tissues but not in the other 10 tissues by the polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) method and following direct sequencing. The mean p21 Cip1 mRNA expression level in tumor tissues was significantly suppressed compared to that of non-tumor tissues, irrespective of p53 gene mutations. In p53 gene mutation-detected cases, the mean expression level of p21 Cip1 mRNAs of tumor tissues was about 60% of that of cases without p53 gene mutation. Moreover, the relative mRNA expression levels of p21 Cip1 significantly decreased as the pathohistological stages progressed by Dukes' staging system, while in patients with liver metastasis these levels were significantly suppressed compared to those of patients without organ metastasis. These results indicate that reduced expression of p21 Cip1 mRNA is critical for growth activity and malignant potential of human colorectal carcinoma, and that the decrease in p21 Cip1 mRNA level is due to p53 gene mutation as well as other mechanisms during human colorectal carcinogenesis.

Adult↗

PubMed2002

Multidrug resistance 3 gene mutation 1712delT and estrogen receptor alpha gene polymorphisms in Finnish women with obstetric cholestasis.

OBJECTIVE: To investigate the contribution of the estrogen receptor alpha (ERalpha) polymorphism in the development of obstetric cholestasis and to determine whether multidrug resistance 3 (MDR3) gene 1712delT mutation detected in French patients is also present in Finnish women with obstetric cholestasis. STUDY DESIGN: In a retrospective case-control study, two ERalpha polymorphisms and MDR3 gene mutation 1712delT were investigated in healthy control women (N = 47) and in women with diagnosis of obsteric cholestasis (N = 57). PvuII and XbaI polymorphisms in ERalpha gene were evaluated in genomic DNA by using the polymerase chain reaction (PCR). In addition, the frequencies in the general population in our area are presented for comparison. RESULTS: None of the ERalpha genotypes or alleles was significantly over-represented in obstetric cholestasis. When the two ERalpha gene polymorphisms were analyzed in parallel, six genotype combinations were recognized, and the distribution of these genotype combinations did not reveal statistically significant differences between the cases and controls (P = 0.612). No patient or control was heterozygous or homozygous for the mutant allele in the MDR3 gene. CONCLUSION: The present data indicate that polymorphism of the ERalpha gene and MDR3 gene 1712delT mutation are unlikely to play any significant role in obstetric cholestasis in affected Finnish women. Further work to identify explanatory factors is of particular interest.

ATP Binding Cassette Transporter, Subfamily B↗

PubMedDate not supplied

Transposable elements as mutator genes in evolution.

Strains of the bacterium Escherichia coli harbouring genes that increase mutation rates are known to have an evolutionary advantage in chemostat competition over otherwise isogeneic strains with lower mutation rates. This advantage is frequency-dependent, the mutator strain being favoured only above a starting ratio of approximately 5 x 10(-5), and it results from the fact that the necessary beneficial mutations cannot be generated in a mutator population below a certain size. Here we consider the possibility that the mutagenic properties of transposable elements confer an advantage in the same manner as mutator genes. A previous report has shown that the transposon Tn5 increases the fitness of E. coli in chemostats, although the reason for this effect has not been established. Our results show that the transposon Tn10 also confers an advantage in chemostats. In addition, we find that (1) this advantage, like that associated with mutator genes, is frequency-dependent, (2) whenever the Tn10 strains win, a segment of Tn10, probably its IS10 sequences, has undergone transposition to a new site, (3) the new insertions converge into a site contained within a 3.2 kilobase (kb) PvuII fragment of the genome, and (4) no transpositions are detected when the Tn10 population loses. We conclude that Tn10 confers an advantage by increasing the mutation rate of the host bacterium.

Biological Evolution↗

PubMed2001

Superoxide dismutase gene mutations in Italian patients with familial and sporadic amyotrophic lateral sclerosis: identification of three novel missense mutations.

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disorder affecting motor neurons. The majority of the patients are sporadic cases (SALS), while 5-10% of the patients have a family history of ALS (familial ALS or FALS). Mutations in the gene coding for cytoplasmic Cu/Zn superoxide dismutase (SOD1) have been identified in about 20% of FALS cases. We found SOD1-gene mutations in five of 34 unrelated FALS, and in two of 44 SALS patients. Three FALS patients carried the previously described A4V (two cases) and L84F mutations (one case), while two FALS patients carried new missense mutations: a G12R substitution in exon 1, and a F45C substitution in exon 2, respectively. The newly identified mutations were both associated with a slowly progressive disease course. Two SALS patients carried the homozygous D90A and the heterozygous I113T mutation, respectively. In addition, in one SALS patient we identified an A95T amino acid substitution, that is apparently a non-pathogenic SOD1 variant. Our study increases the number of ALS-associated SOD1 gene mutations.

Adult↗

PubMed2002

Multidrug resistance 3 gene mutation 1712delT and estrogen receptor alpha gene polymorphisms in Finnish women with obstetric cholestasis.

OBJECTIVE: To investigate the contribution of the estrogen receptor alpha (ERalpha) polymorphism in the development of obstetric cholestasis and to determine whether multidrug resistance 3 (MDR3) gene 1712delT mutation detected in French patients is also present in Finnish women with obstetric cholestasis. STUDY DESIGN: In a retrospective case-control study, two ERalpha polymorphisms and MDR3 gene mutation 1712delT were investigated in healthy control women (N=47) and in women with diagnosis of obstetric cholestasis (N=57). PvuII and XbaI polymorphisms in ERalpha gene were evaluated in genomic DNA by using the polymerase chain reaction (PCR). In addition, the frequencies in the general population in our area are presented for comparison. RESULTS: None of the ERalpha genotypes or alleles was significantly over-represented in obstetric cholestasis. When the two ERalpha gene polymorphisms were analyzed in parallel, six genotype combinations were recognized, and the distribution of these genotype combinations did not reveal statistically significant differences between the cases and controls (P=0.612). No patient or control was heterozygous or homozygous for the mutant allele in the MDR3 gene. CONCLUSION: The present data indicate that polymorphism of the ERalpha and MDR3 genes 1712delT mutation are unlikely to play any significant role in obstetric cholestasis in affected Finnish women. Further work to identify explanatory factors is of particular interest.

ATP Binding Cassette Transporter, Subfamily B↗

PubMed2004

K-ras gene mutation enhances motility of immortalized airway cells and lung adenocarcinoma cells via Akt activation: possible contribution to non-invasive expansion of lung adenocarcinoma.

Point mutations of the K-ras gene, which are found in 10 to 30% of lung adenocarcinomas, are regarded as being an early event during the carcinogenesis. Autonomous vigorous motility of neoplastic cells, as well as growth and survival advantages, are considered to be necessary for cancer development and progression. The present study describes the contributions of the K-ras gene mutation and its downstream pathway via phosphatidylinositol 3-OH kinase (PI3K)-Akt to the cell motility in an immortalized human peripheral airway epithelial cell (HPL1D) and lung adenocarcinoma cells (A549, H820, TKB6, and TKB14). We have also evaluated the relationship between pathological events and the K-ras-Akt pathway using surgically resected lung tumors. The HPL1D cells transfected with the mutated K-ras gene (HPL-V12) showed a significant increase in cell motility compared to those transfected with empty vector (HPL-E) or wild-type K-ras gene (HPL-K). The enhanced motility in the HPL-V12 cells was markedly reduced by either treatment with inhibitors of ras, PI3K, and/or MEK, or by transfection with the dominant-negative mutant Akt (dnAkt). The lung adenocarcinoma cells bearing the K-ras gene mutation (A549 and H820) showed consistently higher levels of cell motilities than those without the mutation (TKB6 and TKB14), and the motility of A549 and H820 cells were significantly inhibited by dnAkt transfection. These results suggest that the K-ras gene mutation could enhance the motility of neoplastic cells through a pathway involving PI3K-Akt. Actually, among the surgically resected lung tumors, the adenocarcinomas with the K-ras gene mutation tended to show a higher frequency and intensity of immunoreactivity for phosphorylated Akt (p-ser473Akt) than those without the mutation, supporting the in vitro observation that the mutated K-ras can activate the PI3K-Akt pathway. Immunoreactivity for p-ser473Akt was also seen in the pre-malignant and early lesions at a frequency similar to that in the advanced lung adenocarcinomas,. No correlation was seen between p-ser473Akt immunoreactivity and lymphatic/organ metastasis or prognosis. These results taken together suggest that the K-ras-Akt pathway might facilitate the motility of neoplastic cells during the early period of carcinogenesis in lung adenocarcinomas, and may contribute to their non-invasive expansion along the alveolar septa, rather than invasion or metastasis.

Adenocarcinoma↗

PubMed2000

Lack of SOD1 gene mutations and activity alterations in two Italian families with amyotrophic lateral sclerosis.

Amyotrophic lateral sclerosis (ALS) is a progressive fatal disorder, which results from the degeneration of motor neurons in the brain and spinal cord. Approximately 20% of the inherited autosomal dominant cases are due to mutations within the gene coding for Cu/Zn superoxide dismutase 1 (SOD1), a cytosolic homodimeric enzyme that catalyzes the dismutation of toxic superoxide anion. We investigated the presence of SOD1 gene mutations and activity alterations in two unrelated families of ALS patients from Elba, an island of central Italy. No mutation in SOD1 exon 1 to 5 and no activity alteration were observed in all members of the two analyzed ALS families (FALS). These data show an apparent heterogeneous distribution of ALS patients with SOD1 gene mutations among different populations and suggest that another genetic locus could be involved in the disease.

Amyotrophic Lateral Sclerosis↗

PubMed2006

Correlation between phenotypic heterogeneity and gene mutational characteristics in familial hemophagocytic lymphohistiocytosis (FHL).

BACKGROUND: Classification of familial hemophagocytic lymphohistiocytosis (FHL) into FHL2, FHL3, and other subtypes based on genetic abnormalities has recently become possible. We studied the phenotypic differences among these subtypes in Japan. METHODS: Forty patients clinically diagnosed with FHL were analyzed. Perforin abnormality was screened by flow cytometric analysis and/or DNA sequencing in these patients, and those without perforin abnormalities were further examined for the presence of mutations in the Munc13-4 gene by DNA sequencing. The correlation between clinical features and genetic subtypes was investigated. RESULTS: Of the 40 HLH patients, 11 showed perforin gene mutations (classified as FHL2) and ten had Munc13-4 gene mutations (FHL3), but neither mutation was noted in 19 patients (non-FHL2/3). Although the majority of the patients developed the disease before the age of 1 year, the onset in three FHL2 patients with missense mutations was late (7, 11, and 12 years). Incidence of deficient natural killer cell activity was higher in FHL2 patients (9/9 FHL2, 4/9 FHL3, and 6/17 non-FHL2/3; P = 0.005). The serum levels of ferritin and soluble interleukin-2 receptor were significantly higher in FHL2 patients with nonsense perforin mutations compared to other subgroups (P < or = 0.05). Epstein-Barr virus infection was involved in 8 of the 40 HLH patients: one FHL2, one FHL3, and six non-FHL2/3. CONCLUSIONS: Although clinical features of FHL3 appear to be homogeneous, the heterogeneous clinical features of FHL2 depend upon the nature of perforin gene mutations. Characterization of the non-FHL2/3 group with regard to FHL1 or other novel gene mutations remains to be conducted.

Child↗

PubMed2004

Arg120stop nonsense mutation in the RP2 gene: mutational hotspot and germ line mosaicism?

Mutations in the RP2 gene account for up to 20% of X-linked recessive retinitis pigmentosa (RP). Arg120stop is to date the most frequently reported mutation found in RP2. Mutation screening was performed during the course of a large screening program of retinal degenerative disorders (RDDs) in South Africa using exon 1 and 2 of RP2 in 20 unrelated families with an X-linked mode of retinal degenerative inheritance. Direct sequencing analysis revealed a C-->T transition at position 358 in the proband in a family of German origin. Subsequent analysis revealed that this Arg120stop mutation cosegregated with the disease in an additional affected family member. The nonsense mutation, Arg120stop, could not however, be detected in the somatic cells of the obligate carrier female. This, the first report of a germ line mutation for a family with RP, has many implications for genetic counseling of retinal degeneration (RD). To avoid inaccurate risk assessment for RP due to epigenetic events, such as the rare occurrence of germ line mosaicism, genetic counseling in families with XLRP should always be guided by molecular testing.

Adult↗

PubMed2000

[Study on the relationship between CD44v6, p53 gene mutation and ovarian carcinoma metastasis].

OBJECTIVE: To explore the relationship between CD44v6 expression, p53 gene mutation, cell ploidy and ovarian metastasis. METHODS: Eighty-five ovarian specimens (20 normal specimens, 20 benign tumors, 20 non-metastatic carcinomas and 25 metastatic carcinomas) were collected. Cell ploidy and the distribution of cell population in each stage of cell cycle were detected by flow cytometry. By using techniques such as reverse transcription-polymerase chain reaction, southern blot and image analysis, the quantitative and qualitative expression of CD44v6 were determined; the mutation of p53 gene in the ovarian specimens was also determined by polymerase chain reaction-single strand conformation polymorphism with silver staining. RESULTS: In the normal ovarian specimens, benign tumors, non-metastatic and metastatic carcinomas, the positive rates of CD44v6 expression and p53 gene mutation were 0%, 10%, 75%, 88% and 0%, 5%, 40%, 60%, respectively, both increased gradually. The mean dark density in the non-metastatic (3,820 +/- 289) and metastatic (10,132 +/- 1,521) groups was significantly different (P < 0.01). In the positive and negative CD44v6 ovarian carcinoma groups, the mean carcinoma cell percentage at the G2M stage was 5.90% and 5.06% (P > 0.05), mean aneuploidy carcinoma cell percentage was 57% and 50% (P > 0.05) respectively. In the mutated and non-mutated p53 gene groups, their mean cell population at the G2M stage was 11.15% and 5.85% (P < 0.05), mean aneuploidy carcinoma cell percentage was 74% and 36% (P < 0.05), respectively. CONCLUSIONS: The expression of CD44v6 is closely related to carcinoma metastasis. The relationship between CD44v6 expression, p53 gene mutation and carcinoma metastasis can be involved in the different mechanism. As compared to mutated p53 gene, CD44v6 appears to be more suitable as a metastatic marker.

Adult↗