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Alisa M Goldstein

Publications and source records attributed to Alisa M Goldstein.

48 records · Page 3Linked to original sources

Allelic loss on chromosome 13q14 and mutation in deleted in cancer 1 gene in esophageal squamous cell carcinoma.

Previous studies have shown frequent allelic loss on chromosome 13 in esophageal squamous cell carcinoma (ESCC). We assessed the frequency of allelic loss on chromosome 13q14 and mutations of deleted in cancer 1 (DICE1) (also found on 13q14) in ESCC patients to determine if this candidate tumor suppressor gene has a role in the development of ESCC, and whether this gene was an inactivation target for allelic loss on chromosome 13q14. Initially, we examined allelic loss at five markers flanking DICE1 in 56 ESCC patients from Shanxi Province, China, and then examined the entire coding sequence of this gene for mutations using polymerase chain reaction-single-strand confirmation polymorphism (PCR-SSCP) analysis and DNA sequencing. Subsequently, we extended our evaluation to an additional 80 ESCC patients and 232 healthy individuals to confirm the germline variant found in the initial 56 ESCC patients. The frequencies of allelic loss were 71, 58, and 75% for D13S325, D13S757, and D13S887, respectively, in the initial 56 ESCC patients studied. Overall, 73% of informative patients had loss of heterozygosity (LOH) for at least one of these three markers. Somatic mutations were identified in three patients (3/56, 5%), and one novel polymorphism was identified in 3% of ESCC patients (4/136) and 3% of healthy individuals (6/232). We conclude that DICE1 mutations occur in ESCC but are infrequent. The candidate tumor suppressor gene corresponding to the frequent allelic loss on chromosome 13q14 in ESCC remains unknown.

Alleles↗

Robustness of inference on measured covariates to misspecification of genetic random effects in family studies.

Family studies to identify disease-related genes frequently collect only families with multiple cases. It is often desirable to determine if risk factors that are known to influence disease risk in the general population also play a role in the study families. If so, these factors should be incorporated into the genetic analysis to control for confounding. Pfeiffer et al. [2001 Biometrika 88: 933-948] proposed a variance components or random effects model to account for common familial effects and for different genetic correlations among family members. After adjusting for ascertainment, they found maximum likelihood estimates of the measured exposure effects. Although it is appealing that this model accounts for genetic correlations as well as for the ascertainment of families, in order to perform an analysis one needs to specify the distribution of random genetic effects. The current work investigates the robustness of the proposed model with respect to various misspecifications of genetic random effects in simulations. When the true underlying genetic mechanism is polygenic with a small dominant component, or Mendelian with low allele frequency and penetrance, the effects of misspecification on the estimation of fixed effects in the model are negligible. The model is applied to data from a family study on nasopharyngeal carcinoma in Taiwan.

Analysis of Variance↗

Evidence for a familial esophageal cancer susceptibility gene on chromosome 13.

Previous segregation analyses of pedigrees from areas of China where esophageal squamous cell carcinoma (ESCC) rates are extraordinarily high suggested a Mendelian mode of transmission. We initiated a search for a major ESCC gene by conducting a genome-wide scan in ESCC tumors. Chromosome 13 showed loss of heterozygosity (LOH) in 95% of microsatellite markers, the highest frequency of LOH on any chromosome. In the current study, we established a high-resolution deletion map using 107 markers on 13q and compared LOH frequency by family history of upper gastrointestinal cancer. Overall allelic loss was significantly higher in those with a positive (versus negative) family history, suggesting the presence of an inherited tumor suppressor gene on 13q in ESCC.

Carcinoma, Squamous Cell↗

Identification of somatic mutations of the RNF6 gene in human esophageal squamous cell carcinoma.

We mapped a tumor suppressor gene locus to an 800-kb interval on human chromosome 13q12.11 for esophageal squamous cell carcinoma (ESCC). Two genes, ML-1 and RNF6, are located within this 800-kb interval. We analyzed both genes for the presence of mutations in 24 ESCC primary tumors and 16 tumor cell lines by directly sequencing the PCR products that were amplified from each exon. No mutation was detected in ML-1. In contrast, three somatic mutations in the RNF6 gene were detected in the ESCC primary tumors, and one mutation was also found in a tumor cell line. Identification of multiple somatic mutations in RNF6 suggests that RNF6 is a potential tumor suppressor gene involved in the pathogenesis of ESCC.

Carcinoma, Squamous Cell↗

Analysis of mutations and identification of several polymorphisms in the putative promoter region of the P34CDC2-related CDC2L1 gene located at 1P36 in melanoma cell lines and melanoma families.

Chromosome 1 abnormalities are the most commonly detected aberrations in many cancers including malignant melanoma. Partial deletions and an allelic loss of the chromosome 1p36 region observed in melanoma indicate the presence of putative tumor suppressor gene(s) in this region. A candidate gene, CDC2L1, which encodes PITSLRE proteins related to p34(cdc2), is mapped to 1p36. To determine whether CDC2L1 mutation is involved in melanoma development, we examined 20 melanoma cell lines and 11 members of melanoma-prone families linked to chromosome 1p36. Mutation analysis throughout the entire coding region of the CDC2L1 gene revealed only 1 mutation (C-->T at nucleotide location 97 of exon 7, Ser-->Leu) in the melanoma cell line UACC 903 out of 20 melanoma cell lines and 6 melanoma cases. However, 4 polymorphic nucleotide changes, C-48T, G-53C, T-103C and T-210C, in the putative promoter region of CDC2L1 were identified. The 4 variants were located within or beside the conserved binding sites of transcription factors TCF11, MZF1 and TAAC box, indicating their potential effects on the regulation of CDC2L1 expression. No aberrant methylation of the CDC2L1 CpG island in the promoter region was observed by sodium bisulfite genomic sequencing. These results indicate that mutations are rare in the CDC2L1 gene in these melanoma cell lines and melanoma families and that the aberrant cytosine methylation of the CDC2L1 CpG island is not the mechanism of CDC2L1 repression in melanoma. The contribution of 4 promoter polymorphisms to the transcriptional regulation of the gene and its association with melanoma warrants further investigation.

CDC2 Protein Kinase↗

Geographical variation in the penetrance of CDKN2A mutations for melanoma.

BACKGROUND: Germline mutations in the CDKN2A gene, which encodes two proteins (p16INK4A and p14ARF), are the most common cause of inherited susceptibility to melanoma. We examined the penetrance of such mutations using data from eight groups from Europe, Australia and the United States that are part of The Melanoma Genetics Consortium. METHODS: We analyzed 80 families with documented CDKN2A mutations and multiple cases of cutaneous melanoma. We modeled penetrance for melanoma using a logistic regression model incorporating survival analysis. Hypothesis testing was based on likelihood ratio tests. Covariates included gender, alterations in p14ARF protein, and population melanoma incidence rates. All statistical tests were two-sided. RESULTS: The 80 analyzed families contained 402 melanoma patients, 320 of whom were tested for mutations and 291 were mutation carriers. We also tested 713 unaffected family members for mutations and 194 were carriers. Overall, CDKN2A mutation penetrance was estimated to be 0.30 (95% confidence interval (CI) = 0.12 to 0.62) by age 50 years and 0.67 (95% CI = 0.31 to 0.96) by age 80 years. Penetrance was not statistically significantly modified by gender or by whether the CDKN2A mutation altered p14ARF protein. However, there was a statistically significant effect of residing in a location with a high population incidence rate of melanoma (P =.003). By age 50 years CDKN2A mutation penetrance reached 0.13 in Europe, 0.50 in the United States, and 0.32 in Australia; by age 80 years it was 0.58 in Europe, 0.76 in the United States, and 0.91 in Australia. CONCLUSIONS: This study, which gives the most informed estimates of CDKN2A mutation penetrance available, indicates that the penetrance varies with melanoma population incidence rates. Thus, the same factors that affect population incidence of melanoma may also mediate CDKN2A penetrance.

Australia↗

Mutations in SUFU predispose to medulloblastoma.

The sonic hedgehog (SHH) signaling pathway directs the embryonic development of diverse organisms and is disrupted in a variety of malignancies. Pathway activation is triggered by binding of hedgehog proteins to the multipass Patched-1 (PTCH) receptor, which in the absence of hedgehog suppresses the activity of the seven-pass membrane protein Smoothened (SMOH). De-repression of SMOH culminates in the activation of one or more of the GLI transcription factors that regulate the transcription of downstream targets. Individuals with germline mutations of the SHH receptor gene PTCH are at high risk of developmental anomalies and of basal-cell carcinomas, medulloblastomas and other cancers (a pattern consistent with nevoid basal-cell carcinoma syndrome, NBCCS). In keeping with the role of PTCH as a tumor-suppressor gene, somatic mutations of this gene occur in sporadic basal-cell carcinomas and medulloblastomas. We report here that a subset of children with medulloblastoma carry germline and somatic mutations in SUFU (encoding the human suppressor of fused) of the SHH pathway, accompanied by loss of heterozygosity of the wildtype allele. Several of these mutations encode truncated proteins that are unable to export the GLI transcription factor from nucleus to cytoplasm, resulting in the activation of SHH signaling. SUFU is a newly identified tumor-suppressor gene that predisposes individuals to medulloblastoma by modulating the SHH signaling pathway through a newly identified mechanism.

Base Sequence↗

A natural history of melanomas and dysplastic nevi: an atlas of lesions in melanoma-prone families.

BACKGROUND: Few long-term clinical and histologic data for melanocytic lesions have been available based on the mutation status of families at an increased risk of melanoma. In the current study, the authors describe the clinical and histologic features of dysplastic nevi and melanoma over time in families at an increased risk of melanoma with differing germline mutations in CDKN2A, CDK4, or not yet identified genes. METHODS: Thirty-three families with > 2 living members with invasive melanoma were evaluated clinically and followed prospectively for up to 25 years. All the participants were evaluated by the same study team at the Clinical Center of the National Institutes of Health or in local clinics. After informed consent was obtained, family members (n = 844) were examined and photographed. Blood was obtained for genetic studies; genotyping for CDKN2A and CDK4 was performed. Sequential photographs of melanocytic lesions were taken as part of the clinical evaluations. When melanocytic lesions were removed, the histology was reviewed. Representative photographs and photomicrographs were selected for six classes of lesions and three mutation groups. RESULTS: All the families were found to have members with dysplastic nevi and melanoma; 17 had mutations in CDKN2A, 2 had mutations in CDK4, and 14 had no mutations in either gene identified. The majority of dysplastic nevi either remain stable or regress; few change in a manner that should cause concern for melanoma. With careful surveillance, melanomas can be found early. CONCLUSIONS: The melanomas and dysplastic nevi that were found to occur in the study families did not appear to vary by the type of mutation identified in the families.

Cyclin-Dependent Kinase 4↗

High prevalence of the G101W germline mutation in the CDKN2A (P16(ink4a)) gene in 62 Italian malignant melanoma families.

CDKN2A germline mutation frequency estimates are commonly based on families with several melanoma cases. When we started counseling in a research setting on gene susceptibility analysis in northern and central Italy, however, we mostly found small families with few cases. Here we briefly characterize those kindred, estimate CDKN2A/CDK4 mutation test yields, and provide indications on the possibility of implementing formal DNA testing for melanoma-prone families in Italy. In September 1995 we started genetic counseling in a research setting at our Medical Genetics Center. Screening for CDKN2A/CDK4 mutations was performed on families with two melanoma patients, one of whom was younger than 50 years at onset, the other complying with one of the following: 1) being a first-degree relative, 2) having an additional relative with pancreatic cancer, or 3) having multiple primary melanomas. Sixty-two of 67 (80%) melanoma cases met our criteria. Four previously described CDKN2A mutations (G101W, R24P, V126D, and N71S) were found in 21 of the 62 families (34%) with a high prevalence of G101W (18/21). The percentage of families with two melanoma cases/family harboring a mutation was low (7%, 2/27), but rose to 45% (9/20) if one of the melanoma patients carried multiple melanomas or if pancreatic cancer was present in that family. In the 15 families with three melanoma cases the presence of a mutation was higher (67%, 10/15) and reached 100% in the 4 families with four or more melanoma cases. Our results suggest that CDKN2A/CDK4 counseling-based mutational analysis may be reasonably efficient also for families with two melanoma cases, if one patient carries multiple melanomas or if pancreatic cancer is present in the family.

Adolescent↗

HLA-DR, HLA-DQ, and TAP genes in familial Hodgkin disease.

The HLA region has long been implicated in sporadic and familial Hodgkin disease (HD), with recent case-control studies suggesting that HLA class II loci predispose to sporadic nodular sclerosis HD (NSHD). To determine whether this predisposition extends to familial HD, HLA class II loci (DRB1, DQA1, DQB1, DRB3, DRB4, and DRB5) and transporter associated with antigen processing (TAP) loci (TAP1, TAP2) were investigated in 100 members of 16 families with at least 2 confirmed cases of HD. With the use of the transmission disequilibrium test, evidence for linkage disequilibrium with familial HD and, in particular, familial NSHD was obtained for the DRB1*1501-DQA1*0102-DQB1*0602 haplotype, the TAP1 allele encoding Ile at residue 333, and the DRB5-0101 allele. These 3 markers were in linkage disequilibrium and may not represent independent susceptibility regions. Use of a family-based approach excludes population stratification as an explanation for these findings.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

Infrequent mutation in the BRCA2 gene in esophageal squamous cell carcinoma.

PURPOSE: Previous studies have shown a high rate of allelic loss in esophageal squamous cell carcinoma (ESCC) in the vicinity of the BRCA2 gene. We aimed to assess whether the tumor suppressor gene BRCA2 was the inactivation target for allelic loss observed on chromosome 13q in ESCC. EXPERIMENTAL DESIGN: We examined the entire coding sequence of the BRCA2 gene for mutations using single-strand conformation polymorphism analysis and DNA sequencing in 56 ESCC patients from Shanxi, China. RESULTS: Eight mutations were identified in 5 patients (9%), including 3 with germ-line mutations and 2 with only somatic mutations. However, all but 1 of the mutations were missense or silent changes and of unknown significance. Evidence for potential biallelic inactivation was seen in only 4 (7%) cases. CONCLUSIONS: BRCA2 mutations occur in ESCC but are infrequent and of unknown consequence. The putative target tumor suppressor gene corresponding to the high rate of chromosome 13q allelic loss remains unknown.

Alleles↗