[Show abstract][Hide abstract] ABSTRACT: Clonality of multicentric breast cancer has traditionally been difficult to assess. We aimed to assess this using analysis of TP53 status (expression and mutation status). These results were then incorporated into an analysis of prognostic factors in multicentric tumours in a 10-year follow up study. Clonal status of multicentric breast cancer foci (n = 88 foci) was determined by immunohistochemical and molecular studies of TP53 in a total of 40 patients. Prognostic factors from these patients were also compared with 80 age- and stage-matched controls with unicentric breast cancer from the Royal Marsden NHS Foundation Trust Breast Cancer Database. Our results indicate that multicentric breast cancer foci were polyclonal within an individual patient in at least 10 patients (25%) with respect to immunohistochemical staining and in four patients (10%) with respect to abnormal band shifts on single strand conformational polymorphism (SSCP) molecular analysis. No individual variable was predictive of multicentric or unicentric disease. However, there was a worse overall survival in the multicentric breast cancer patients in whom at least two cancer foci stained positively on TP53 immunohistochemistry compared with the matched control group (P = 0.04). In conclusion, these results suggest that a proportion of multicentric breast cancer foci are polyclonal with respect to TP53 status and that TP53 over-expression predicts for a poorer prognosis in multicentric breast cancer.
Full-text · Article · Nov 2010 · Breast Cancer Research and Treatment
[Show abstract][Hide abstract] ABSTRACT: Formalin-fixed prostate biopsies are frequently the only tissue collected at the time of prostate cancer diagnosis. There is therefore a requirement for techniques that allow the use of these prostate biopsy specimens in a high-throughput analysis of immunohistochemical and fluorescence-in-situ-hybridisation-detected biomarkers.
The authors have previously described methods that allow tissue microarray (TMA) construction from prostate biopsies. Here, we describe significant technical innovations that provide an easier and more robust system of biopsy-TMA construction.
The TMAs produced are of a high density (up to 104 cores each, 8 × 13) and allow a multiplex analysis of biomarkers in the context of clinical trials.
Preview · Article · Nov 2010 · Journal of clinical pathology
[Show abstract][Hide abstract] ABSTRACT: Microseminoprotein-beta (MSMB) regulates apoptosis and using genome-wide association studies the rs10993994 single nucleotide polymorphism in the MSMB promoter has been linked to an increased risk of developing prostate cancer. The promoter location of the risk allele, and its ability to reduce promoter activity, suggested that the rs10993994 risk allele could result in lowered MSMB in benign tissue leading to increased prostate cancer risk.
MSMB expression in benign and malignant prostate tissue was examined using immunohistochemistry and compared with the rs10993994 genotype. Urinary MSMB concentrations were determined by ELISA and correlated with urinary PSA, the presence or absence of cancer, rs10993994 genotype and age of onset. MSMB levels in prostate tissue and urine were greatly reduced with tumourigenesis. Urinary MSMB was better than urinary PSA at differentiating men with prostate cancer at all Gleason grades. The high risk allele was associated with heterogeneity of MSMB staining and loss of MSMB in both tissue and urine in benign prostate.
These data show that some high risk alleles discovered using genome-wide association studies produce phenotypic effects with potential clinical utility. We provide the first link between a low penetrance polymorphism for prostate cancer and a potential test in human tissue and bodily fluids. There is potential to develop tissue and urinary MSMB for a biomarker of prostate cancer risk, diagnosis and disease monitoring.
[Show abstract][Hide abstract] ABSTRACT: The germline BRCA2 mutation is associated with increased prostate cancer (PrCa) risk. We have assessed survival in young PrCa cases with a germline mutation in BRCA2 and investigated loss of heterozygosity at BRCA2 in their tumours.
Two cohorts were compared: one was a group with young-onset PrCa, tested for germline BRCA2 mutations (6 of 263 cases had a germline BRAC2 mutation), and the second was a validation set consisting of a clinical set from Manchester of known BRCA2 mutuation carriers (15 cases) with PrCa. Survival data were compared with a control series of patients in a single clinic as determined by Kaplan-Meier estimates. Loss of heterozygosity was tested for in the DNA of tumour tissue of the young-onset group by typing four microsatellite markers that flanked the BRCA2 gene, followed by sequencing.
Median survival of all PrCa cases with a germline BRCA2 mutation was shorter at 4.8 years than was survival in controls at 8.5 years (P=0.002). Loss of heterozygosity was found in the majority of tumours of BRCA2 mutation carriers. Multivariate analysis confirmed that the poorer survival of PrCa in BRCA2 mutation carriers is associated with the germline BRCA2 mutation per se.
BRCA2 germline mutation is an independent prognostic factor for survival in PrCa. Such patients should not be managed with active surveillance as they have more aggressive disease.
Full-text · Article · Sep 2010 · British Journal of Cancer
[Show abstract][Hide abstract] ABSTRACT: A novel oncogenetic clinic was established in 2002 at the Royal Marsden NHS Foundation Trust offering advice and specialist follow-up for families with a germline mutation in BRCA1 or BRCA2. The remit of this multidisciplinary clinic, staffed by individuals in both oncology and genetics, is to provide individualised screening recommendations, support in decision making, risk reducing strategies, cascade testing, and an extensive research portfolio.
A retrospective analysis was performed to evaluate uptake of genetic testing, risk reducing surgery and cancer prevalence in 346 BRCA1/BRCA2 families seen between January 1996 and December 2006.
661 individuals attended the clinic and 406 mutation carriers were identified; 85.8% mutation carriers have chosen to attend for annual follow-up. 70% of mutation carriers elected for risk reducing bilateral salpingo-oophorectomy (RRBSO). 32% of unaffected women chose risk reducing bilateral mastectomy. 32% of women with breast cancer chose contralateral risk reducing mastectomy at time of diagnosis. Some women took over 8 years to decide to have surgery. 91% of individuals approached agreed to participate in research programmes.
A novel specialist clinic for BRCA1/2 mutation carriers has been successfully established. The number of mutation positive families is increasing. This, and the high demand for RRBSO in women over 40, is inevitably going to place an increasing demand on existing health resources. Our clinic model has subsequently been adopted in other centres and this will greatly facilitate translational studies and provide a healthcare structure for management and follow-up of such people who are at a high cancer risk.
Full-text · Article · Jul 2010 · Journal of Medical Genetics
[Show abstract][Hide abstract] ABSTRACT: Prostate cancer diagnosis is routinely made by the histopathological examination of formalin fixed needle biopsy specimens. Frequently this is the only cancer tissue available from the patient for the analysis of diagnostic and prognostic biomarkers. There is, therefore, an urgent need for methods that allow the high-throughput analysis of these biopsy samples using immunohistochemical (IHC) markers and fluorescence in situ hybridisation (FISH) analysis based markers.
A method that allows the construction of tissue microarrays (TMAs) from diagnostic prostate needle biopsy cores has previously been reported. However, the technique only allows the production of low-density biopsy TMAs with a maximum of 20 cores per TMA. Here two methods are presented that allow the rapid and uniform production of biopsy TMAs containing between 54 and 72 biopsy cores. IHC and FISH techniques were used to detect biomarker status.
Biopsy TMAs were constructed from prostate needle biopsy specimens taken from 102 patients entered into an active surveillance trial and 201 patients in a radiotherapy trial. The detection rate for cancer in slices of these biopsy TMAs was 66% and 79% respectively. Slices of a biopsy TMA prepared from biopsies from active surveillance patients were used to detect multiple IHC markers and to score TMPRSS2-ERG fusion status in a FISH-based assay.
The construction of biopsy TMAs provides an effective method for the multiplex analysis of IHC and FISH markers and for their assessment as prognostic biomarkers in the context of clinical trials.
[Show abstract][Hide abstract] ABSTRACT: Previous studies have identified multiple loci on 8q24 associated with prostate cancer risk. We performed a comprehensive analysis of SNP associations across 8q24 by genotyping tag SNPs in 5,504 prostate cancer cases and 5,834 controls. We confirmed associations at three previously reported loci and identified additional loci in two other linkage disequilibrium blocks (rs1006908: per-allele OR = 0.87, P = 7.9 x 10(-8); rs620861: OR = 0.90, P = 4.8 x 10(-8)). Eight SNPs in five linkage disequilibrium blocks were independently associated with prostate cancer susceptibility.
[Show abstract][Hide abstract] ABSTRACT: Radiotherapy dose escalation improves tumour control in prostate cancer but with increased toxicity. Boosting focal tumour only may allow dose escalation with acceptable toxicity. Intensity-modulated radiotherapy can deliver this, but visualization of the tumour remains limiting. CT or conventional MRI techniques are poor at localizing tumour, but dynamic contrast-enhanced MRI (DCE-MRI) may be superior. 18 patients with prostate cancer had T(2) weighted (T2W) and DCE-MRI prior to prostatectomy. The prostate was sectioned meticulously so as to achieve accurate correlation between imaging and pathology. The accuracy of DCE-MRI for cancer detection was calculated by a pixel-by-pixel correlation of quantitative DCE-MRI parameter maps and pathology. In addition, a radiologist interpreted the DCE-MRI and T2W images. The location of tumour on imaging was compared with histology, and the accuracy of DCE-MRI and T2W images was then compared. Pixel-by-pixel comparison of quantitative parameter maps showed a significant difference between the benign peripheral zone and tumour for the parameters K(trans), v(e) and k(ep). Calculation of areas under the receiver operating characteristic curve showed that the pharmacokinetic parameters were only "fair" discriminators between cancer and benign gland. Interpretation of DCE-MRI and T2W images by a radiologist showed DCE-MRI to be more sensitive than T2W images for tumour localization (50% vs 21%; p = 0.006) and similarly specific (85% vs 81%; p = 0.593). The superior sensitivity of DCE-MRI compared with T2W images, together with its high specificity, is arguably sufficient for its use in guiding radiotherapy boosts in prostate cancer.
Full-text · Article · Mar 2009 · The British journal of radiology
[Show abstract][Hide abstract] ABSTRACT: There is evidence that a substantial part of genetic predisposition to prostate cancer (PCa) may be due to lower penetrance genes which are found by genome-wide association studies. We have recently conducted such a study and seven new regions of the genome linked to PCa risk have been identified. Three of these loci contain candidate susceptibility genes: MSMB, LMTK2 and KLK2/3. The MSMB and KLK2/3 genes may be useful for PCa screening, and the LMTK2 gene might provide a potential therapeutic target. Together with results from other groups, there are now 23 germline genetic variants which have been reported. These results have the potential to be developed into a genetic test. However, we consider that marketing of tests to the public is premature, as PCa risk can not be evaluated fully at this stage and the appropriate screening protocols need to be developed. Follow-up validation studies, as well as studies to explore the psychological implications of genetic profile testing, will be vital prior to roll out into healthcare.
No preview · Article · Jan 2009 · Asian Journal of Andrology
[Show abstract][Hide abstract] ABSTRACT: Prostate cancer is the most frequently diagnosed male cancer, and its clinical outcome is difficult to predict. The disease may involve the inappropriate expression of genes that normally control the proliferation of epithelial cells in the basal layer and their differentiation into luminal cells. Our aim was to identify novel basal cell markers and assess their prognostic and functional significance in prostate cancer. RNA from basal and luminal cells isolated from benign tissue by immunoguided laser-capture microdissection was subjected to expression profiling. We identified 112 and 267 genes defining basal and luminal populations, respectively. The transcription factor TEAD1 and the ubiquitin ligase c-Cbl were identified as novel basal cell markers. Knockdown of either marker using siRNA in prostate cell lines led to decreased cell growth in PC3 and disrupted acinar formation in a 3D culture system of RWPE1. Analyses of prostate cancer tissue microarray staining established that increased protein levels of either marker were associated with decreased patient survival independent of other clinicopathological metrics. These data are consistent with basal features impacting on the development and clinical course of prostate cancers.
Full-text · Article · Dec 2008 · British Journal of Cancer
[Show abstract][Hide abstract] ABSTRACT: OBJECTIVE
To integrate the mapping of ERG alterations with the collection of expression microarray (EMA) data, as previous EMA analyses have failed to consider the genetic heterogeneity and complex patterns of ERG alteration frequently found in cancerous prostates.MATERIALS AND METHODS
We determined genome-wide expression levels with GeneChip Human Exon 1.0 ST arrays (Affymetrix, Santa Clara, CA, USA) using RNA prepared from 35 specimens of prostate cancer from 28 prostates.RESULTSThe expression profiles showed clustering, in unsupervised hierarchical analyses, into two distinct prostate cancer categories, with one group strongly associated with indicators of poor clinical outcome. The two categories are not tightly linked to ERG status. By analysis of the data we identified a subgroup of cancers lacking ERG rearrangements that showed an outlier pattern of SPINK1 mRNA expression. There was a major distinction between ERG rearranged and non-rearranged cancers that involves the levels of expression of genes linked to exposure to β-oestradiol, and to retinoic acid.CONCLUSIONS
Expression profiling of prostate cancer samples containing single patterns of ERG alterations can provide novel insights into the mechanism of prostate cancer development, and support the view that factors other than ERG status are the major determinants of poor clinical outcome.
No preview · Article · Nov 2008 · BJU International
[Show abstract][Hide abstract] ABSTRACT: Active surveillance provides a unique opportunity to study biomarkers of prostate cancer behaviour, although only small volumes of tumor tissue are typically available. We have evaluated a technique for constructing tissue microarrays (TMAs) from needle biopsies for assessing immunohistochemical markers in localized prostate cancer managed by active surveillance. TMAs were constructed from diagnostic prostate biopsies for 60 patients with localized prostatic adenocarcinoma in a prospective cohort study of active surveillance. Radical treatment was recommended for a prostate-specific antigen (PSA) velocity greater than 1 ng ml(-1) per year or adverse histology in repeat biopsies, defined as Gleason score > or =4+3 or >50% of cores involved. Sections from the TMAs were stained with H&E, P63/AMACR and Ki-67. Time to radical treatment was analysed with respect to clinical characteristics and Ki-67 LI. At a median follow up of 36 months, 25/60 (42%) patients had received radical treatment. On univariate analysis, PSA density (P=0.001), Gleason score (P=0.001), clinical T stage (P=0.01), Ki-67 LI (P=0.02) and initial PSA (P=0.04) were associated with time to radical treatment. On multivariate analysis, PSA density (P=0.01), Ki-67 LI (P=0.03) and Gleason score (P=0.04) were independent determinants of progression to radical treatment. TMAs constructed from prostate needle biopsies can be used to assess immunohistochemical markers in localized prostate cancer managed by active surveillance. Ki-67 LI merits further study as a possible biomarker of early prostate cancer behaviour.
Full-text · Article · Sep 2008 · Prostate cancer and prostatic diseases