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Biomedical subjects

Laura J Van't Veer

Publications and source records attributed to Laura J Van't Veer.

6 recordsLinked to original sources
PubMed2006

Breast cancer survival and tumor characteristics in premenopausal women carrying the CHEK2*1100delC germline mutation.

PURPOSE: Women carrying a CHEK2*1100delC germline mutation have an increased risk of developing breast cancer. This study aims to determine the proportion of CHEK2*1100delC carriers in a premenopausal breast cancer population, unselected for family history of breast cancer, and to investigate tumor characteristics and disease outcome with sufficient follow-up. PATIENTS AND METHODS: We identified a retrospective cohort of 1,479 patients, who received surgery for invasive breast cancer between 1970 and 1994. All patients were diagnosed before age 50. Paraffin-embedded tissue blocks were collected for DNA isolation (normal tissue), subsequent CHEK2*1100delC analysis, and tumor revision. Median follow-up was 10.1 years. RESULTS: We detected a CHEK2*1100delC germline mutation in 54 patients (3.7%). Tumor characteristics of CHEK2*1100delC carriers did not differ significantly from those of noncarriers. CHEK2*1100delC carriers had a two-fold increased risk (hazard ratio [HR], 2.1; 95% CI, 1.0 to 4.3; P = .049) of developing a second breast cancer and they had worse recurrence-free survival (HR, 1.7; 95% CI, 1.2 to 2.4; P = .006) and worse breast cancer-specific survival (HR, 1.4; 95% CI, 1.0 to 2.1; P = .072) compared with noncarriers. The poorer disease outcome of CHEK2*1100delC carriers could not be explained by the increased risk of second breast cancer. CONCLUSION: Our study, which is representative for the premenopausal breast cancer population, reveals approximately 4% CHEK2*1100delC carriers have an increased risk of second breast cancer and a worse long-term recurrence-free survival rate. Their identification at time of diagnosis and prolonged intensive follow-up should be considered to optimize clinical management.

Adult↗
PubMed2006

Converting a breast cancer microarray signature into a high-throughput diagnostic test.

BACKGROUND: A 70-gene tumor expression profile was established as a powerful predictor of disease outcome in young breast cancer patients. This profile, however, was generated on microarrays containing 25,000 60-mer oligonucleotides that are not designed for processing of many samples on a routine basis. RESULTS: To facilitate its use in a diagnostic setting, the 70-gene prognosis profile was translated into a customized microarray (MammaPrint) containing a reduced set of 1,900 probes suitable for high throughput processing. RNA of 162 patient samples from two previous studies was subjected to hybridization to this custom array to validate the prognostic value. Classification results obtained from the original analysis were then compared to those generated using the algorithms based on the custom microarray and showed an extremely high correlation of prognosis prediction between the original data and those generated using the custom mini-array (p < 0.0001). CONCLUSION: In this report we demonstrate for the first time that microarray technology can be used as a reliable diagnostic tool. The data clearly demonstrate the reproducibility and robustness of the small custom-made microarray. The array is therefore an excellent tool to predict outcome of disease in breast cancer patients.

Biomarkers, Tumor↗
PubMed2006

Cross-validated Cox regression on microarray gene expression data.

This paper describes how penalized Cox regression, in combination with cross-validated partial likelihood can be employed to obtain reliable survival prediction models for high dimensional microarray data. The suggested procedure is demonstrated on a breast cancer survival data set consisting of 295 tumours as collected in the National Cancer Institute in Amsterdam and previously reported in more general papers. The main aim of this paper it to show how generally accepted biostatistical procedures can be employed to analyse high-dimensional data.

Breast Neoplasms↗
PubMed2006

The single-nucleotide polymorphism 309 in the MDM2 gene contributes to the Li-Fraumeni syndrome and related phenotypes.

Li-Fraumeni syndrome (LFS) is an autosomal-dominant cancer predisposition syndrome of which the majority is caused by TP53 germline mutations and is characterised by different tumour types occurring at relatively young age. Recently, it was shown that a single-nucleotide polymorphism (SNP) in the MDM2 gene, SNP309 (T>G variation), was associated with accelerated tumour formation in LFS patients who carry a TP53 germline mutation. To confirm this finding in different populations, we screened 25 Dutch and 11 Finnish TP53 mutation carriers for the presence of the SNP309 G allele in the MDM2 gene. Additionally, we investigated whether the SNP309 G allele plays a role in 72 Dutch TP53-negative LFS and LFS-related patients. In the TP53 germline mutation carriers, a significant difference was seen in the mean age of tumour onset for the SNP309 G allele group, that is, 29.7 years as compared to the SNP309 homozygous T group 45.5 years (P=0.005). In patients of LFS and LFS-related TP53-negative families, no difference was seen in the mean age of tumour onset. However, this TP53-negative group did show a significantly higher percentage of SNP309 homozygotes (G/G) compared to the general population (P=0.02). In conclusion, TP53 germline mutation carriers who have an SNP309 G allele have an earlier onset of tumour formation. The higher prevalence of MDM2 SNP309 homozygous G/G carriers in the TP53-negative group suggests that this allele contributes to cancer susceptibility in LFS and LFS-related families.

Adult↗
PubMed2005

Molecular portraits and 70-gene prognosis signature are preserved throughout the metastatic process of breast cancer.

Microarray analysis has been shown to improve risk stratification of breast cancer. Breast tumors analyzed by hierarchical clustering of expression patterns of "intrinsic" genes have been reported to subdivide into at least four molecular subtypes that are associated with distinct patient outcomes. Using a supervised method, a 70-gene expression profile has been identified that predicts the later appearance or absence of clinical metastasis in young breast cancer patients. Here, we show that distant metastases display both the same molecular breast cancer subtype as well as the 70-gene prognosis signature as their primary tumors. Our results suggest that the capacity to metastasize is an inherent feature of most breast cancers. Furthermore, our data imply that poor prognosis breast carcinomas classified either by the intrinsic gene set or the 70 prognosis genes represent distinct disease entities that seem sustained throughout the metastatic process.

Breast Neoplasms↗