WAP Four-disulfide Core Domain Research Articles

Identifying Subpopulations with Distinct Response to Treatment Using Plasma Biomarkers in Acute Heart Failure: Results from the PROTECT Trial

BackgroundOver the last 50 years, clinical trials of novel interventions for acute heart failure (AHF) have, with few exceptions, been neutral or shown harm. We hypothesize that this might be related to a differential response to pharmacological therapy.MethodsWe studied the magnitude of treatment effect of rolofylline across clinical characteristics and plasma biomarkers in 2033 AHF patients and derived a biomarker-based responder sum score model. Treatment response was survival from all-cause mortality through day 180.ResultsIn the overall study population, rolofylline had no effect on mortality (HR 1.03, 95% CI 0.82–1.28, p = 0.808). We found no treatment interaction across clinical characteristics, but we found interactions between several biomarkers and rolofylline. The biomarker-based sum score model included TNF-R1α, ST2, WAP four-disulfide core domain protein HE4 (WAP-4C), and total cholesterol, and the score ranged between 0 and 4. In patients with score 4 (those with increased TNF-R1α, ST2, WAP-4C, and low total cholesterol), treatment with rolofylline was beneficial (HR 0.61, 95% CI 0.40–0.92, p = 0.019). In patients with score 0, treatment with rolofylline was harmful (HR 5.52, 95% CI 1.68–18.13, p = 0.005; treatment by score interaction p < 0.001). Internal validation estimated similar hazard ratio estimates (0 points: HR 5.56, 95% CI 5.27–7–5.87; 1 point: HR 1.31, 95% CI 1.25–1.33; 2 points: HR 0.75, 95% CI 0.74–0.76; 3 points: HR 1.13, 95% CI 1.11–1.15; 4 points, HR 0.61, 95% CI 0.61–0.62) compared to the original data.ConclusionBiomarkers are superior to clinical characteristics to study treatment heterogeneity in acute heart failure.

Estrogen receptor β, a regulator of androgen receptor signaling in the mouse ventral prostate.

As estrogen receptor β-/- (ERβ-/-) mice age, the ventral prostate (VP) develops increased numbers of hyperplastic, fibroplastic lesions and inflammatory cells. To identify genes involved in these changes, we used RNA sequencing and immunohistochemistry to compare gene expression profiles in the VP of young (2-mo-old) and aging (18-mo-old) ERβ-/- mice and their WT littermates. We also treated young and old WT mice with an ERβ-selective agonist and evaluated protein expression. The most significant findings were that ERβ down-regulates androgen receptor (AR) signaling and up-regulates the tumor suppressor phosphatase and tensin homolog (PTEN). ERβ agonist increased expression of the AR corepressor dachshund family (DACH1/2), T-cadherin, stromal caveolin-1, and nuclear PTEN and decreased expression of RAR-related orphan receptor c, Bcl2, inducible nitric oxide synthase, and IL-6. In the ERβ-/- mouse VP, RNA sequencing revealed that the following genes were up-regulated more than fivefold: Bcl2, clusterin, the cytokines CXCL16 and -17, and a marker of basal/intermediate cells (prostate stem cell antigen) and cytokeratins 4, 5, and 17. The most down-regulated genes were the following: the antioxidant gene glutathione peroxidase 3; protease inhibitors WAP four-disulfide core domain 3 (WFDC3); the tumor-suppressive genes T-cadherin and caveolin-1; the regulator of transforming growth factor β signaling SMAD7; and the PTEN ubiquitin ligase NEDD4. The role of ERβ in opposing AR signaling, proliferation, and inflammation suggests that ERβ-selective agonists may be used to prevent progression of prostate cancer, prevent fibrosis and development of benign prostatic hyperplasia, and treat prostatitis.

WAP four-disulfide core domain protein 2 gene(WFDC2) is a target of estrogen in ovarian cancer cells.

BackgroundWAP four-disulfide core domain protein 2 (WFDC2) shows a tumor-restricted upregulated pattern of expression in ovarian cancer.MethodsWe investigated the role of estradiol (E2) on cell growth in estrogen-sensitive or estrogen-insensitive ovarian cancer cell lines. Real-time (RT)-PCR and western blotting were used to examine the expression of WFDC2 at RNA and protein levels. Growth traits of cells transfected with WFDC2-shRNA or blank control were assessed using MMT arrays. Cell apoptosis was analyzed using annexin V-FITC/PI and flow cytometry. Estrogen receptor expression was evaluated using RT-PCR and flow cytometry. Apoptosis-related proteins induced by E2 directly and indirectly were determined using an antibody array comparing cells transfected with WFDC2- shRNA or a blank control.ResultsHigh-dose (625 ng/ml) E2 increased the expression of WFDC2 in HO8910 cells at both the mRNA and protein levels. However, E2 had no effect on WFDC2 expression in estrogen-insensitive SKOV3 cells. Of interest, knockdown of WFDC2 enabled a considerable estrogen response in SKOV3 cells in terms of proliferation, similar to estrogen-responsive HO8910 cells. This transformation of SKOV3 cells into an estrogen-responsive phenotype was accompanied by upregulation of estrogen receptor beta (ERß) and an effect on cell apoptosis under E2 treatment by regulating genes related to cell proliferation and apoptosis.ConclusionsWe postulate that increased WFDC2 expression plays an important role in altering the estrogen pathway in ovarian cancer, and the identification of WFDC2 as a new player in endocrine-related cancer encourages further studies on the significance of this gene in cancer development and therapy.Electronic supplementary materialThe online version of this article (doi:10.1186/s13048-015-0210-y) contains supplementary material, which is available to authorized users.

Molecular Markers of Tubulointerstitial Fibrosis and Tubular Cell Damage in Patients with Chronic Kidney Disease.

In chronic kidney disease (CKD), progressive nephron loss causes glomerular sclerosis, as well as tubulointerstitial fibrosis and progressive tubular injury. In this study, we aimed to identify molecular changes that reflected the histopathological progression of renal tubulointerstitial fibrosis and tubular cell damage. A discovery set of renal biopsies were obtained from 48 patients with histopathologically confirmed CKD, and gene expression profiles were determined by microarray analysis. The results indicated that hepatitis A virus cellular receptor 1 (also known as Kidney Injury Molecule-1, KIM-1), lipocalin 2 (also known as neutrophil gelatinase-associated lipocalin, NGAL), SRY-box 9, WAP four-disulfide core domain 2, and NK6 homeobox 2 were differentially expressed in CKD. Their expression levels correlated with the extent of tubulointerstitial fibrosis and tubular cell injury, determined by histopathological examination. The expression of these 5 genes was also increased as kidney damage progressed in a rodent unilateral ureteral obstruction model of CKD. We calculated a molecular score using the microarray gene expression profiles of the biopsy specimens. The composite area under the receiver operating characteristics curve plotted using this molecular score showed a high accuracy for diagnosing tubulointerstitial fibrosis and tubular cell damage. The robust sensitivity of this score was confirmed in a validation set of 5 individuals with CKD. These findings identified novel molecular markers with the potential to contribute to the detection of tubular cell damage and tubulointerstitial fibrosis in the kidney.

Serum HE4: An Independent Prognostic Factor in Non-Small Cell Lung Cancer.

Human epididymis secretory protein 4 (HE4) is a secreted glycosylated protein encoded by the WAP four-disulfide core domain 2 (WFDC2) gene, located on a chromosome 20 segment that is frequently amplified in many cancers. This study aimed at determining serum HE4 prognostic value in non-small cell lung cancer (NSCLC), following the REMARK guidelines. Serum samples from 346 consecutive patients with histologically proven and previously untreated NSCLC and 41 patients with benign pulmonary disease were collected at the Montpellier-Nimes Academic Hospital. Work-up investigations performed to determine the disease characteristics and treatment algorithms were congruent with international guidelines. HE4 levels in serum were measured with an ELISA test (Fujirebio Diagnostics) that uses two monoclonal antibodies, 2H5 and 3D8, against the C-WFDC domain of HE4. The area under the ROC curve (i.e., overall ability of HE4 to discriminate between controls and patients) was 0.78 (95% confidence interval [CI], 0.738–0.821; z test P <0.0001). Serum HE4 levels were significantly higher in patients with worse performance status, advanced TNM stage and positive nodal status. In the Cox model, overall survival was shorter in patients with high pretreatment serum HE4 (above 140 pmol/L) than in patients with serum H4 level ≤ 140 pmol/L [median survival: 17.7 weeks (95% CI, 11.9 to 24.9) and 46.4 weeks (95% CI, 38.6 to 56.3), respectively; hazard ratio: 1.48 (95% CI, 1.12 to 1.95) for high HE4; adjusted P = 0.0057]. High serum HE4 level at diagnosis is an independent determinant of poor prognosis in NSCLC.

Identification of CTLA2A, DEFB29, WFDC15B, SERPINA1F and MUP19 as Novel Tissue-Specific Secretory Factors in Mouse.

Secretory factors in animals play an important role in communication between different cells, tissues and organs. Especially, the secretory factors with specific expression in one tissue may reflect important functions and unique status of that tissue in an organism. In this study, we identified potential tissue-specific secretory factors in the fat, muscle, heart, lung, kidney and liver in the mouse by analyzing microarray data from NCBI’s Gene Expression Omnibus (GEO) public repository and searching and predicting their subcellular location in GeneCards and WoLF PSORT, and then confirmed tissue-specific expression of the genes using semi-quantitative PCR reactions. With this approach, we confirmed 11 lung, 7 liver, 2 heart, 1 heart and muscle, 7 kidney and 2 adipose and liver-specific secretory factors. Among these genes, 1 lung-specific gene - CTLA2A (cytotoxic T lymphocyte-associated protein 2 alpha), 3 kidney-specific genes - SERPINA1F (serpin peptidase inhibitor, Clade A, member 1F), WFDC15B (WAP four-disulfide core domain 15B) and DEFB29 (defensin beta 29) and 1 liver-specific gene - MUP19 (major urinary protein 19) have not been reported as secretory factors. These genes were tagged with hemagglutinin at the 3’end and then transiently transfected to HEK293 cells. Through protein detection in cell lysate and media using Western blotting, we verified secretion of the 5 genes and predicted the potential pathways in which they may participate in the specific tissue through data analysis of GEO profiles. In addition, alternative splicing was detected in transcripts of CTLA2A and SERPINA1F and the corresponding proteins were found not to be secreted in cell culture media. Identification of novel secretory factors through the current study provides a new platform to explore novel secretory factors and a general direction for further study of these genes in the future.

The human epididymis protein 4 acts as a prognostic factor and promotes progression of gastric cancer.

Human epididymis protein 4 (HE4), represented as an epididymis-specific gene and designated a WAP four-disulfide core domain protein 2 (WFDC2), is amplified in many tumors. However, little is known about its clinical significance and biological function in gastric carcinomas. We found that HE4 was more commonly observed in gastric carcinoma tissues than in normal tissues and was significantly correlated with Lauren classification, TNM stage, and tumor size by immunohistochemistry. The overall survival rate of patients with HE4 low expression was significantly higher than that of the patients with HE4 high expression. In addition, silencing of HE4 expression inhibits cell proliferation and migration and enhances cell apoptosis. Subsequent studies reveal that the Src, Akt, and Erk1/2 signaling may be involved with pro-survival and anti-apoptotic effects of the HE4 on gastric cancer cells. Taken together, this study provides new evidence on promotive effects of the HE4 on gastric cancer progression and indicates that HE4 might be a promising prognostic factor for gastric cancer diagnosis.

Abstract 18278: The Prognostic Value Of WFDC2, a New Biomarker for Heart Failure

Aim s: Identification of plasma biomarkers that help to stratify heart failure (HF) patients may help to improve treatment. We investigated the prognostic value of WAP four-disulfide core domain protein 2 (WFDC2, also termed HE4), a biomarker not previously described in HF. Methods: Data of 567 patients participating in the Coordinating study evaluating outcomes of Advising and Counselling in Heart failure (COACH) study were analysed. Patients had been hospitalized for HF and were followed for 18 months. Several plasma biomarker levels were determined using an ELISA platform. The primary endpoint of this study was a composite of all-cause mortality and HF hospitalization. Results: Mean age was 71±11 years, 62% were males, mean LVEF was 33±14%, and mean eGFR was 54±20 mL/minute. WFDC2 was identified as a biomarker that showed strong correlation with HF severity, according to NYHA functional class and BNP levels ( P &lt; 0.001). WFDC2 also showed a strong positive correlation with GDF15 ( P &lt;0.001). In addition, WFDC2 levels correlated with kidney function (BUN, creatinine, and eGFR; all P &lt;0.001). Cox regression analysis revealed that a doubling of WFDC2 levels was associated with a hazard ratio (HR) of 1.73 (1.53-1.95) for the primary outcome ( P &lt;0.001). After correction for age, gender, BNP and eGFR the HR was 1.46 (1.23-1.72) ( P &lt;0.001) and after additional adjustment for GDF15 the HR lowered to 1.30 (1.07-1.59) ( P =0.009). The AUC in the ROC curve analysis increased from 0.7123 to 0.7375 when WFDC2 was included to the clinical model ( P =0.068). The IDI and NRI metrics for reclassification showed highly significant improvements when WFDC2 was added to the clinical model (NRI=0.12, P &lt;0.001) and this remained significant after inclusion of BNP to this model. Conclusion: WFDC2 plasma levels are correlated with markers of HF severity, show prognostic value, and improve risk assessment in HF.

WAP four-disulfide core domain protein 2 mediates the proliferation of human ovarian cancer cells through the regulation of growth- and apoptosis-associated genes

The WAPfour-disulfide core domain protein2 (WFDC2) is frequently overexpressed in epithelial ovarian cancer cells and has been proposed as a potential biomarker. The biological function of WFDC2 in tumor progression remains unclear. In this study, the stable expression of short hairpin RNA (shRNA) against WFDC2 in the human ovarian SKOV3 cell line was established. Cell proliferation invitro was determined by MTT assay. Cell cycle and apoptosis were analyzed by FACS. The expression of genes related to cell proliferation and survival was detected by real-time RT-PCR and western blotting. Invivo tumor growth assay was performed by establishing WFDC2-knockdown xenografts in nude mice and monitoring tumor growth. The expression of WFDC2, Ki67 and activated caspase-3 was analyzed by immunohistochemistry in order to determine the role of WFDC2 in proliferation and apoptosis. Our results revealed that the silencing of WFDC2 abolished ovarian cancer cell proliferation, suppressing tumor formation and growth in ovarian cancer cells both invitro and invivo. The knockdown of WFDC2 induced upregulation of Fasl and the downregulation of cyclin D1 activated caspase-3 and Ki67. These results indicate that WFDC2 plays a crucial role in tumor formation and growth in ovarian cancer cells. WFDC2 may be a potential therapeutic target for epithelial ovarian cancer.

WFDC2 is differentially expressed in the mammary gland of the tammar wallaby and provides immune protection to the mammary gland and the developing pouch young

WAP four disulfide core domain 2 (WFDC2) is a four disulfide core (4-DSC) protein secreted in the milk of the tammar wallaby. It is comprised of two 4-DSC domains assigned domain III at the NH2-terminal end and domain II at the COOH-terminal end. The WFDC2 gene was expressed only during pregnancy, early lactation, towards the end of lactation and involution. The WFDC2 protein showed antibacterial activity against Staphylococcus aureus, Salmonella enterica and Pseudomonas aeruginosa and this activity resided with domain II. There was no antibacterial activity detected against Enterococcus faecalis. The observed expression pattern of tammar WFDC2 and its antibacterial activity suggests a role to either reduce mastitis in the mammary gland caused by S. aureus or to protect the gut of the young at a time when it is not immune-competent. The latter effect could be achieved without disturbing the balance of commensal gut flora such as E. faecalis.

WFDC1 (WAP four-disulfide core domain 1)

Review on WFDC1 (WAP four-disulfide core domain 1), with data on DNA, on the protein encoded, and where the gene is implicated.

Microarray expression identification of differentially expressed genes in serous epithelial ovarian cancer compared with bulk normal ovarian tissue and ovarian surface scrapings

The lack of reliable early detection of ovarian cancer and the absence of specific symptoms result in diagnosis of ovarian cancer at advanced stage in the majority of the patients. Through gene expression profiling we can identify important genes that may help understand the evolution from normal ovarian tissue to ovarian cancer. The gene expression profiles of 7 normal ovaries and 26 ovaries with serous epithelial ovarian cancer (SEOC) were examined by cDNA microarrays using supervised and unsupervised analysis, with sequential significance filtering. Real-time RT-PCR was used to measure and compare the expression levels of 5 selected genes: WAP four-disulfide core domain protein HE4 (WAP, up-regulated), secreted phosphoprotein 1 (SPP1, osteopontin; up-regulated), activin A receptor, type I (ACVR1, up-regulated), tumor necrosis factor (TNF superfamily, member 2; TNF, up-regulated) and decorin (DCN, down-regulated) in 4 epithelial scrapings and in 6 bulk-extracted normal ovaries. The gene expression profile of SEOC was not dependent on the stage of the disease at diagnosis. A supervised microarray data analysis identified a subset of 329 genes showing significant differential expression between SEOC samples and bulk normal ovarian tissue and ovarian surface scrapings, including several new genes such as TNFalpha and activin A receptor type I. The real-time RT-PCR for the up-regulated genes did not differ significantly between normal ovarian epithelial scrapings and bulk-extracted ovaries. However, decorin showed a statistically significant difference (P=0.0073) in expression between epithelial scrapings and bulk-extracted ovaries. Previously uncharacterized genes are associated with the malignant phenotype of SEOC. Bulk normal ovarian tissue may serve as control for SEOC tissue in gene expression profiling. Gene expression profiling and sequential statistical analyses of gene subsets can identify new genes and molecular pathways affecting development of SEOC. The genes of interest can be potential targets for future research of SEOC.

Dissimilarity in gene expression profiles of lung adenocarcinoma in japanese men and women

Although clinical differences in lung cancer between men and women have been noted, few studies have examined the sex dissimilarity using gene expression analysis. The purpose of this study was to determine the different molecular carcinogenic mechanisms involved in lung cancers in Japanese men and women. Patients who received surgery for stage I lung adenocarcinoma were included. RNA was extracted from cancerous and normal tissue, and gene expression was then examined with oligonucleotide microarray analysis. A quantitative polymerase chain reaction assay was performed. In a microarray analysis of tissue from 13 men and 6 women, 12 genes were under-expressed and 24 genes were overexpressed in lung adenocarcinoma in women compared with men. Genes related to cell cycle were present in underexpressed genes, and genes related to apoptosis, ubiquitination, and metabolism were observed in overexpressed genes. Of interest among the selected genes were WAP four-disulfide core domain 2 (WFDC2) and major histocompatibility complex, class II, DM alpha (HLA-DMA); these genes were classified into 2 groups by hierarchical clustering analysis. Expression of WFDC2 in nonsmokers was significantly higher than that in smokers (P=0.023). However, there was no significant difference in HLA-DMA expression between smokers and nonsmokers. Thirty-six genes that characterize lung adenocarcinoma by sex were selected. This information may contribute to the development of novel diagnostic techniques and treatment modalities that consider sex differences in lung adenocarcinoma.

Novel epididymal protease inhibitors with Kazal or WAP family domain

The epididymal maturation of spermatozoa is regulated by changes in the luminal ion concentration and the processing of the sperm surface membrane by several glycosidases and proteases. In the present study, we identified five novel protease inhibitors that are highly expressed in the mouse epididymis. Four of the proteins were found to belong to the Kazal protease inhibitor family and were named SPINK8, SPINK10, SPINK11, and SPINK12, whereas one of the proteins, WFDC10, contained the WAP four-disulfide core domain structure. The novel genes showed very specific segmental expression patterns. The expression of all the five genes was regulated by testis-derived factors and decreased after gonadectomy. With the exception of Spink11, mRNA levels could be restored by testosterone replacement. We hypothesize that the protease inhibitors discovered represent a group of epididymal genes that contribute to the regulation of sperm maturation by regulating the proteolytic processing of the sperm membrane during epididymal transit.

Selection of potential markers for epithelial ovarian cancer with gene expression arrays and recursive descent partition analysis.

Advanced-stage epithelial ovarian cancer has a poor prognosis with long-term survival in less than 30% of patients. When the disease is detected in stage I, more than 90% of patients can be cured by conventional therapy. Screening for early-stage disease with individual serum tumor markers, such as CA125, is limited by the fact that no single marker is up-regulated and shed in adequate amounts by all ovarian cancers. Consequently, use of multiple markers in combination might detect a larger fraction of early-stage ovarian cancers. To identify potential candidates for novel markers, we have used Affymetrix human genome arrays (U95 series) to analyze differences in gene expression of 41,441 known genes and expressed sequence tags between five pools of normal ovarian surface epithelial cells (OSE) and 42 epithelial ovarian cancers of different stages, grades, and histotypes. Recursive descent partition analysis (RDPA) was performed with 102 probe sets representing 86 genes that were up-regulated at least 3-fold in epithelial ovarian cancers when compared with normal OSE. In addition, a panel of 11 genes known to encode potential tumor markers [mucin 1, transmembrane (MUC1), mucin 16 (CA125), mesothelin, WAP four-disulfide core domain 2 (HE4), kallikrein 6, kallikrein 10, matrix metalloproteinase 2, prostasin, osteopontin, tetranectin, and inhibin] were similarly analyzed. The 3-fold up-regulated genes were examined and four genes [Notch homologue 3 (NOTCH3), E2F transcription factor 3 (E2F3), GTPase activating protein (RACGAP1), and hematological and neurological expressed 1 (HN1)] distinguished all tumor samples from normal OSE. The 3-fold up-regulated genes were analyzed using RDPA, and the combination of elevated claudin 3 (CLDN3) and elevated vascular endothelial growth factor (VEGF) distinguished the cancers from normal OSE. The 11 known markers were analyzed using RDPA, and a combination of HE4, CA125, and MUC1 expression could distinguish tumor from normal specimens. Expression at the mRNA level in the candidate markers was examined via semiquantitative reverse transcription-PCR and was found to correlate well with the array data. Immunohistochemistry was performed to identify expression of the genes at the protein level in 158 ovarian cancers of different histotypes. A combination of CLDN3, CA125, and MUC1 stained 157 (99.4%) of 158 cancers, and all of the tumors were detected with a combination of CLDN3, CA125, MUC1, and VEGF. Our data are consistent with the possibility that a limited number of markers in combination might identify >99% of epithelial ovarian cancers despite the heterogeneity of the disease.

Microarray profiling of progesterone-regulated endometrial genes during the rhesus monkey secretory phase

BackgroundIn the endometrium the steroid hormone progesterone (P), acting through its nuclear receptors, regulates the expression of specific target genes and gene networks required for endometrial maturation. Proper endometrial maturation is considered a requirement for embryo implantation. Endometrial receptivity is a complex process that is spatially and temporally restricted and the identity of genes that regulate receptivity has been pursued by a number of investigators.MethodsIn this study we have used high density oligonucleotide microarrays to screen for changes in mRNA transcript levels between normal proliferative and adequate secretory phases in Rhesus monkey artificial menstrual cycles. Biotinylated cRNA was prepared from day 13 and days 21–23 of the reproductive cycle and transcript levels were compared by hybridization to Affymetrix HG-U95A arrays.ResultsOf ~12,000 genes profiled, we identified 108 genes that were significantly regulated during the shift from a proliferative to an adequate secretory endometrium. Of these genes, 39 were up-regulated at days 21–23 versus day 13, and 69 were down-regulated. Genes up-regulated in P-dominant tissue included: secretoglobin (uteroglobin), histone 2A, polo-like kinase (PLK), spermidine/spermine acetyltransferase 2 (SAT2), secretory leukocyte protease inhibitor (SLPI) and metallothionein 1G (MT1G), all of which have been previously documented as elevated in the Rhesus monkey or human endometrium during the secretory phase. Genes down-regulated included: transforming growth factor beta-induced (TGFBI or BIGH3), matrix metalloproteinase 11 (stromelysin 3), proenkephalin (PENK), cysteine/glycine-rich protein 2 (CSRP2), collagen type VII alpha 1 (COL7A1), secreted frizzled-related protein 4 (SFRP4), progesterone receptor membrane component 1 (PGRMC1), chemokine (C-X-C) ligand 12 (CXCL12) and biglycan (BGN). In addition, many novel/unknown genes were also identified. Validation of array data was performed by semi-quantitative RT-PCR of two selected up-regulated genes using temporal (cycle day specific) endometrial cDNA populations. This approach confirmed up-regulation of WAP four-disulfide core domain 2 (WFDC2) and SLPI during the expected window of receptivity.ConclusionThe identification of P-regulated genes and gene pathways in the primate endometrium is expected to be an important first step in elucidating the cellular processes necessary for the development of a receptive environment for implantation.

Frequent somatic mutations in PTEN and TP53 are mutually exclusive in the stroma of breast carcinomas.

We have recently shown that loss of heterozygosity of specific markers, including those at 10q23, 17p13-p15 and 16q24, can occur in the stromal and epithelial compartments of primary invasive breast carcinomas. Here, we demonstrate high frequencies of somatic mutations in TP53 (encoding tumor protein p53) and PTEN (encoding phosphate and tensin homolog) in breast neoplastic epithelium and stroma. Mutations in TP53 and PTEN are mutually exclusive in either compartment. In contrast, mutations in WFDC1 (16q24, encoding WAP four-disulfide core domain 1) occur with low frequency in the stroma.