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Rajal B Shah

Publications and source records attributed to Rajal B Shah.

At least 19 recordsLinked to original sources

Integrative molecular concept modeling of prostate cancer progression.

Despite efforts to profile prostate cancer, the genetic alterations and biological processes that correlate with the observed histological progression are unclear. Using laser-capture microdissection to isolate 101 cell populations, we have profiled prostate cancer progression from benign epithelium to metastatic disease. By analyzing expression signatures in the context of over 14,000 'molecular concepts', or sets of biologically connected genes, we generated an integrative model of progression. Molecular concepts that demarcate critical transitions in progression include protein biosynthesis, E26 transformation-specific (ETS) family transcriptional targets, androgen signaling and cell proliferation. Of note, relative to low-grade prostate cancer (Gleason pattern 3), high-grade cancer (Gleason pattern 4) shows an attenuated androgen signaling signature, similar to metastatic prostate cancer, which may reflect dedifferentiation and explain the clinical association of grade with prognosis. Taken together, these data show that analyzing gene expression signatures in the context of a compendium of molecular concepts is useful in understanding cancer biology.

Androgens↗

Epidermal growth factor receptor (ErbB1) expression in prostate cancer progression: correlation with androgen independence.

BACKGROUND: The role of the epidermal growth factor receptor (ErbB1) in the progression of prostate cancer is incompletely understood. METHODS: Tissue microarrays from hormone-naive and advanced androgen-independent tumors were used to investigate the role of ErbB1 in prostate cancer progression. RESULTS: ErbB1 expression in tumor tissues was strongly associated with hormone-refractory status (odds ratio = 6.67, 95% CI = (2.6, 17.4), P = 0.0001). However, ErbB1 overexpression was not a statistically significant covariate in a multivariate proportional hazards model for biochemical failure of hormone-naïve prostate cancer. Moreover, ErbB1 overexpression was not associated with tumor differentiation (P = 0.44), positive margins (P = 0.53), seminal vesicle invasion (P = 0.69), extraprostatic extension (P = 0.10), or preoperative PSA (P = 0.18) in the hormone-naïve group. CONCLUSIONS: These findings are consistent with a model in which ErbB1 expression increases during the development of the androgen-independent state, and suggest that drugs targeted toward ErbB signaling could be of therapeutic relevance in the management of advanced prostatic carcinoma.

Adult↗

Sclerosing mucoepidermoid carcinoma of the parotid gland.

Mucoepidermoid carcinoma is the most common malignant tumor of the parotid gland. Its clinical behavior is determined by the relative ratio of mucous and epidermoid cells with pathologic high-grade tumors containing a greater proportion of epidermoid cells. Sclerosing mucoepidermoid carcinoma is a rarely reported variant with unclear long-term clinical behavior. A 23-year-old female was found to have a deep lobe parotid mass on imaging studies. Preoperative evaluation was non-diagnostic. Intraoperatively, the tumor was found to be adherent to the lower division of the facial nerve and portions of the posterior digastric muscle. Frozen section specimens showed only squamous metaplasia with background inflammatory fibrosis. Final pathological analysis demonstrated multiple solid and cystic nests and glands within a background of dense, sclerotic, collagenized stroma and inflammatory infiltrate consistent with low-grade sclerosing mucoepidermoid carcinoma. Sclerosing mucoepidermoid carcinoma is a very rare salivary gland tumor with uncertain behavior. Complete surgical excision with tumor-free margins with preservation of the facial nerve (in the absence of clinical invasion) is recommended. Postoperative radiation therapy is suggested for positive or close margins given the adherent nature of the tumor and the risk of recurrence and distant disease found in some case reports. Patients should be followed closely with serial MRI imaging studies of the tumor bed with complete clinical evaluation of the regional lymphatics and chest to evaluate for evidence of recurrence or metastasis.

Adult↗

TMPRSS2:ETV4 gene fusions define a third molecular subtype of prostate cancer.

Although common in hematologic and mesenchymal malignancies, recurrent gene fusions have not been well characterized in epithelial carcinomas. Recently, using a novel bioinformatic approach, we identified recurrent gene fusions between TMPRSS2 and the ETS family members ERG or ETV1 in the majority of prostate cancers. Here, we interrogated the expression of all ETS family members in prostate cancer profiling studies and identified marked overexpression of ETV4 in 2 of 98 cases. In one such case, we confirmed the overexpression of ETV4 using quantitative PCR, and by rapid amplification of cDNA ends, quantitative PCR, and fluorescence in situ hybridization, we show that the TMPRSS2 (21q22) and ETV4 (17q21) loci are fused in this case. This result defines a third molecular subtype of prostate cancer and supports the hypothesis that dysregulation of ETS family members through fusions with TMRPSS2 may be an initiating event in prostate cancer development.

Adenovirus E1A Proteins↗

Perlecan, a candidate gene for the CAPB locus, regulates prostate cancer cell growth via the Sonic Hedgehog pathway.

BACKGROUND: Genetic studies associated the CAPB locus with familial risk of brain and prostate cancers. We have identified HSPG2 (Perlecan) as a candidate gene for CAPB. Previously we have linked Perlecan to Hedgehog signaling in Drosophila. More recently, we have demonstrated the importance of Hedgehog signaling in humans for advanced prostate cancer. RESULTS: Here we demonstrate Perlecan expression in prostate cancer, and its function in prostate cancer cell growth through interaction and modulation of Sonic Hedgehog (SHH) signaling. Perlecan expression in prostate cancer tissues correlates with a high Gleason score and rapid cell proliferation. Perlecan is highly expressed in prostate cancer cell lines, including androgen insensitive cell lines and cell lines selected for metastatic properties. Inhibition of Perlecan expression in these cell lines decreases cell growth. Simultaneous blockade of Perlecan expression and androgen signaling in the androgen-sensitive cell line LNCaP was additive, indicating the independence of these two pathways. Perlecan expression correlates with SHH in tumor tissue microarrays and increased tumor cell proliferation based on Ki-67 immunohistochemistry. Inhibition of Perlecan expression by siRNA in prostate cancer cell lines decreases SHH signaling while expression of the downstream SHH effector GLI1 rescues the proliferation defect. Perlecan forms complexes with increasing amounts of SHH that correlate with increasing metastatic potential of the prostate cancer cell line. SHH signaling also increases in the more metastatic cell lines. Metastatic prostate cancer cell lines grown under serum-starved conditions (low androgen and growth factors) resulted in maintenance of Perlecan expression. Under low androgen, low growth factor conditions, Perlecan expression level correlates with the ability of the cells to maintain SHH signaling. CONCLUSION: We have demonstrated that Perlecan, a candidate gene for the CAPB locus, is a new component of the SHH pathway in prostate tumors and works independently of androgen signaling. In metastatic tumor cells increased SHH signaling correlates with the maintenance of Perlecan expression and more Perlecan-SHH complexes. Perlecan is a proteoglycan that regulates extracellular and stromal accessibility to growth factors such as SHH, thus allowing for the maintenance of SHH signaling under growth factor limiting conditions. This proteoglycan represents an important central regulator of SHH activity and presents an ideal drug target for blocking SHH effects.

Cell Line, Tumor↗

E-cadherin protein expression predicts prostate cancer salvage radiotherapy outcomes.

PURPOSE: Radiotherapy for biochemical prostate cancer recurrence after prostatectomy achieves durable salvage rates of only 40% to 50%. Improved methods of identifying patients unlikely to benefit from salvage radiotherapy are needed. Altered expression of the adhesion molecule E-cadherin may be associated with the invasive and metastatic phenotype. We examined the relationship between E-cadherin expression and outcomes after salvage radiotherapy. MATERIALS AND METHODS: E-cadherin expression was examined by immunohistochemistical analysis of a tissue microarray of prostatectomy tissues from patients who underwent salvage radiotherapy. The relation between E-cadherin staining, other risk factors and biochemical failure after salvage radiotherapy was analyzed using Kaplan-Meier and Cox regression methods. RESULTS: Of 37 analyzable cases 25 showed aberrant E-cadherin expression, while the remainder had normal expression. At a median clinical followup of 40 months univariate analysis demonstrated that E-cadherin staining was not associated with Gleason score, extracapsular extension, surgical margin status, pre-prostatectomy or pre-radiotherapy prostate specific antigen, complete biochemical response after radiotherapy or adjunctive hormonal therapy but it was associated with seminal vesicle invasion. Two-year failure-free survival was 55% in patients with aberrant E-cadherin expression compared with 92% in patients with normal E-cadherin expression (p = 0.02). Multivariate analysis confirmed that aberrant E-cadherin expression was associated with salvage radiotherapy failure (p = 0.03). CONCLUSIONS: Aberrant E-cadherin staining is associated with increased biochemical failure rates after salvage radiotherapy. Patients with biochemical failure after prostatectomy and aberrant E-cadherin expression are likely to have subclinical disseminated disease. Early systemic therapy may be warranted in these patients.

Cadherins↗

Clonality of sarcomatous and carcinomatous elements in sarcomatoid carcinoma of the prostate.

Sarcomatoid carcinomas of the prostate are rare malignancies composed of carcinomatous and sarcomatous elements. Their etiology is uncertain and may represent a single malignant process or a mixture of two distinct malignancies. We report a clinical case of a patient who presented with locally advanced disease and was treated with hormonal and cytotoxic chemotherapy, but ultimately developed distant metastasis and died of the disease. A loss-of-heterozygosity analysis of the primary and metastatic tissues provided compelling evidence that the carcinomatous and sarcomatous elements are clonally related, supporting the hypothesis that a single malignant process underlies the etiology of sarcomatoid carcinoma of the prostate.

Carcinoma↗

A working group classification of focal prostate atrophy lesions.

Focal atrophy is extremely common in prostate specimens. Although there are distinct histologic variants, the terminology is currently nonstandardized and no formal classification has been tested for interobserver reliability. This lack of standardization hampers the ability to study the biologic and clinical significance of these lesions. After informal and formal meetings by a number of the authors, focal atrophy lesions were categorized into 4 distinct subtypes as follows: (i) simple atrophy, (ii) simple atrophy with cyst formation, (iii) postatrophic hyperplasia, and (iv) partial atrophy. In phase 1 of the study, pathologists with varying levels of experience in prostate pathology were invited to view via the Internet a set of "training" images with associated descriptions of lesions considered typical of each subtype. In phase 2 of the study, each participant provided diagnoses on a series of 140 distinct "test" images that were viewed over the Internet. These test images consisted of the 4 subtypes of atrophy and images of normal epithelium, high grade prostatic intraepithelial neoplasia, and carcinoma. The diagnoses for each image from each pathologist were compared with a set of "standard" diagnoses and the kappa statistic was computed. Thirty-four pathologists completed both phases of the study. The interobserver reliability (median kappa) for classification of lesions as normal, cancer, prostatic intraepithelial neoplasia, or focal atrophy was 0.97. The median kappa for the classification of atrophy lesions into the 4 subtypes was 0.80. The median percent agreement with the standard diagnosis for the atrophy subtypes were: simple 60.6%, simple with cyst formation 100%; postatrophic hyperplasia 87.5%; partial atrophy 93.9%. The lower percentage for simple atrophy reflected a propensity to diagnose some of these as simple atrophy with cyst formation. Seven pathologists completed the phase 2 analysis a second time, and their intraobserver reproducibility was excellent. Three of 4 pathologists with low agreement with the standard diagnosis for simple atrophy improved their scores after repeating the analysis after re-examination of the "training set" of images. In conclusion, these criteria for variants of focal prostate atrophy may facilitate studies to examine the relation between various patterns of prostate atrophy and prostate cancer.

Atrophy↗

Prostate-specific antigen, high-molecular-weight cytokeratin (clone 34betaE12), and/or p63: an optimal immunohistochemical panel to distinguish poorly differentiated prostate adenocarcinoma from urothelial carcinoma.

An optimal immunohistochemical panel to distinguish poorly differentiated prostate (PCa) from urothelial (UCa) carcinoma was selected from a panel consisting of prostate-specific antigen (PSA) and prostatic acid phosphatase (PAP), high-molecular-weight cytokeratin (HMWCK), clone 34betaE12, cytokeratin (CK) 7, CK20, p63, and alpha-methylacyl-coenzyme A racemase. The pilot group was composed of poorly differentiated UCa (n = 36) and PCa (n = 42). PSA and PAP stained 95% of PCa vs 0% and 11% of UCa cases, respectively. HMWCK and p63 stained 97% and 92% of UCa vs 2% and 0% of PCa cases respectively. CK7/CK20 coexpression was noted in 50% of UCa cases, whereas 86% of PCa cases were negative with both. A panel of PSA, HMWCK, and p63 was optimal for separating 95% PCa (PSA+/HMWCK and/or p63-) vs 97% UCa (PSA-/HMWCK and/or p63+). This panel was used on 26 diagnostically challenging cases and resolved 81% of cases as UCa vs PCa. The majority of PCa cases retain PSA. Negative PSA with positive HMWCK and/or p63 establishes a diagnosis of UCa.

Adenocarcinoma↗

Whole transcriptome amplification for gene expression profiling and development of molecular archives.

Expression profiling of clinically obtainable tumor specimens has been hindered by the need for microgram quantities of RNA. In vitro transcription (IVT)-based amplifications are most commonly used to amplify small quantities of RNA for microarray analysis. However, significant drawbacks exist with IVT-based amplification, and the need for alternative amplification methods remains. Herein, we validate whole transcriptome amplification (WTA), an exponential amplification technique that produces cDNA libraries and amplified target in 3 to 4 hours from nanogram quantities of total RNA using a combination of cDNA microarrays and quantitative polymerase chain reaction (PCR). We demonstrate that WTA material can serve as a "molecular archive" because a WTA cDNA library can be faithfully amplified through multiple rounds of PCR amplification, allowing it to serve as a bankable and distributable resource. To demonstrate applicability, WTA was combined with laser capture microdissection to profile frozen prostate tissues. Unlike most IVT-based and exponential amplification techniques, WTA does not depend on the presence of a poly-A tail. Thus, we demonstrate that WTA is compatible with artificially degraded RNA and RNA isolated from formalin-fixed paraffin-embedded tissues. Taken together, WTA represents a versatile approach to profile and archive cDNA from minute tumor samples and is compatible with partially degraded RNA.

Biological Specimen Banks↗

Noninvasive detection of TMPRSS2:ERG fusion transcripts in the urine of men with prostate cancer.

We recently reported the identification of recurrent gene fusions in the majority of prostate cancers involving the 5' untranslated region of the androgen-regulated gene TMPRSS2 and the ETS family members ERG, ETV1, and ETV4. Here we report the noninvasive detection of these gene fusions in the urine of patients with clinically localized prostate cancer. By quantitative polymerase chain reaction, we assessed the expression of ERG and TMPRSS2:ERG transcripts in urine samples obtained after prostatic massage from 19 patients (11 prebiopsy and 8 pre-radical prostatectomy) with prostate cancer. We observed a strong concordance between ERG overexpression and TMPRSS2:ERG expression, with 8 of 19 (42%) patients having detectable TMPRSS2:ERG transcripts in their urine. Importantly, by fluorescence in situ hybridization, we confirmed the presence or the absence of TMPRSS2:ERG gene fusions in matched prostate cancer tissue samples from three of three patients with fusion transcripts in their urine and from two of two patients without fusion transcripts in their urine. These results demonstrate that TMPRSS2:ERG gene fusions can be detected in the urine of patients with prostate cancer and support larger studies on prospective cohorts for noninvasive detection of prostate cancer.

5' Untranslated Regions↗

Image-guided biopsy in the evaluation of renal mass lesions in contemporary urological practice: indications, adequacy, clinical impact, and limitations of the pathological diagnosis.

With increasing sophistication of imaging modalities, many small indeterminate renal masses are detected, posing therapeutic dilemmas. Minimally invasive techniques such as radio frequency ablation (RFA) and cryotherapy are increasingly used in such settings, making it essential to classify renal mass in biopsies. We evaluated indications, adequacy, spectrum, and limitations of pathological diagnoses in 52 (79%) of 66 adequate biopsies that impacted management by having conservative therapy (less than total nephrectomy). Indication for biopsies in this group was exclusively for indeterminate mass. Biopsies were categorized as 52% clear cell renal cell carcinoma (RCC); 11% papillary RCC; 23% oncocytic neoplasms, subdivided as oncocytoma (10), chromophobe RCC (1), and cannot rule out RCC (1); 8% spindle cell neoplasms; 2% round blue cell tumors; and 4% inflammatory. After biopsy, 29% underwent nephron-sparing surgery, 36% underwent RFA, and 35% were followed up with observation only. One (2%) unresolved oncocytic neoplasm proved to be a chromophobe RCC in the total nephrectomy. Of the 19 patients, 15 who underwent RFA after diagnostic biopsy subsequently underwent post-RFA biopsy to assess therapy response. Complete ablation at first attempt was achieved in 12 of 15 patients. In contemporary urological practice, biopsies are increasingly performed for incidentally detected renal mass to influence the clinical management. Most biopsies can be classified into clinically relevant categories; however, caution is advised while interpreting oncocytic neoplasms because sampling and tumor heterogeneity may adversely affect interpretation.

Biopsy, Needle↗

Recurrent fusion of TMPRSS2 and ETS transcription factor genes in prostate cancer.

Recurrent chromosomal rearrangements have not been well characterized in common carcinomas. We used a bioinformatics approach to discover candidate oncogenic chromosomal aberrations on the basis of outlier gene expression. Two ETS transcription factors, ERG and ETV1, were identified as outliers in prostate cancer. We identified recurrent gene fusions of the 5' untranslated region of TMPRSS2 to ERG or ETV1 in prostate cancer tissues with outlier expression. By using fluorescence in situ hybridization, we demonstrated that 23 of 29 prostate cancer samples harbor rearrangements in ERG or ETV1. Cell line experiments suggest that the androgen-responsive promoter elements of TMPRSS2 mediate the overexpression of ETS family members in prostate cancer. These results have implications in the development of carcinomas and the molecular diagnosis and treatment of prostate cancer.

Androgens↗

Integrative genomic and proteomic analysis of prostate cancer reveals signatures of metastatic progression.

Molecular profiling of cancer at the transcript level has become routine. Large-scale analysis of proteomic alterations during cancer progression has been a more daunting task. Here, we employed high-throughput immunoblotting in order to interrogate tissue extracts derived from prostate cancer. We identified 64 proteins that were altered in prostate cancer relative to benign prostate and 156 additional proteins that were altered in metastatic disease. An integrative analysis of this compendium of proteomic alterations and transcriptomic data was performed, revealing only 48%-64% concordance between protein and transcript levels. Importantly, differential proteomic alterations between metastatic and clinically localized prostate cancer that mapped concordantly to gene transcripts served as predictors of clinical outcome in prostate cancer as well as other solid tumors.

Disease Progression↗

Laparoscopic and open surgical nephrectomy for xanthogranulomatous pyelonephritis.

BACKGROUND AND PURPOSE: Xanthogranulomatous pyelonephritis (XGP) is a severe, chronic renal-parenchymal infection. Nephrectomy is the treatment of choice. Because of the renal and perirenal inflammatory changes that commonly accompany XGP, the laparoscopic approach is difficult. We compared our experience with laparoscopic and open surgical nephrectomy for XGP. PATIENTS AND METHODS: A retrospective chart review of all adult nephrectomy specimens with the pathologic diagnosis of XGP between January 1997 and May 2003 was performed. Preoperative presentation, operative details, and postoperative recovery and complications were included in the data collection. RESULTS: Three patients approached laparoscopically and eight patients approached with open surgery were found to have XGP on pathologic analysis. The disease was suspected preoperatively in all patients. Among the laparoscopically treated patients, there was 1 (33%) who suffered major complications; this was the only patient who required conversion to open surgery. Among the open-surgical group, there were 2 (22%) major and 3 (33%) minor complications. Postoperative hospitalization was longer in the open-surgical group (mean 13.7 v 4.7 days), and when the case of open conversion was excluded, narcotic use was less in the laparoscopy group. CONCLUSIONS: The treatment of some XGP cases with laparoscopic nephrectomy is a possible, albeit challenging, option. The incidences of intraoperative and postoperative complications were roughly equivalent in the laparoscopic and open-surgery patients in our study. If completed, laparoscopy appears to be associated with decreased postoperative morbidity. However, this may represent selection bias, and larger, prospective studies may better define the suspected benefit.

Adult↗

Use of extended pattern technique for initial prostate biopsy.

PURPOSE: An extended prostate biopsy schema has been advocated at initial prostate biopsy to decrease the rate of false-negative cancer cases. However, critics have raised concerns that this may lead to the greater detection of clinically insignificant cancers. We examined the impact of using an extended pattern schema on cancer detection and also on the finding of smaller and clinically insignificant cancer. MATERIALS AND METHODS: Clinical data, including patient age, race, prebiopsy prostate specific antigen (PSA), digital rectal examination, prostate volume, number of needle cores and biopsy findings were abstracted from the medical records of all patients who underwent prostate biopsy in a 5-year period. Extended pattern prostate biopsy was defined as more than 10 cores. Clinically insignificant cancer was defined as a maximal tumor dimension of 1.0 cm or less, Gleason sum 6 or less and organ confined disease at radical prostatectomy. Adjusted regression models were developed to assess the independent effects of using an extended biopsy pattern on the detection of cancer overall and on the detection of clinically insignificant cancer. RESULTS: A total of 740 men with a mean age of 62.6 years were referred for prostate biopsy. Median PSA was 5.7 ng/ml and prostate volume was 39.7 cc. The OR for detecting prostate cancer was 1.55 (95% CI 1.09 to 2.19) for the extended pattern compared with standard biopsy. Of the subset of 136 patients who underwent radical prostatectomy 12.6% had clinically insignificant cancer. However, in contrast to overall cancer detection, extended pattern prostate biopsy was not found to be associated with an increased risk of detecting smaller or clinically insignificant cancer. PSA density was the single parameter found to be independently associated with the detection of clinically insignificant cancer (95% CI 0.20 to 0.98). CONCLUSIONS: Using an extended prostate biopsy pattern involving more than 10 cores increases the likelihood of detecting prostate cancer. A significant association between more needle cores at initial prostate biopsy and finding smaller and clinically insignificant cancer was not apparent.

Biopsy, Needle↗

Utility of cytokeratin 20 and Ki-67 as markers of urothelial dysplasia.

Reactive urothelial atypia (RUA) can be difficult to differentiate from dysplastic urothelium. The goal was to evaluate the efficacy of cytokeratin 20 (CK20), Ki-67 and E-cadherin (E-Cad) in this regard. Fifty carcinoma in situ (CIS) cases, 50 non-neoplastic urothelia (25 normal, 25 reactive urothelial atypia (RUA)) and 17 atypia of unknown significance (AUS) cases were evaluated. All cases were stained with monoclonal antibodies against Ki-67, CK20 and E-Cad. All (100%) normal urothelia showed normal staining patterns. In the CIS group, 86%, 82% and 20% of cases showed abnormal expression with CK20, Ki-67 and E-Cad, respectively. Both Ki-67 and CK20 were positive in 68% of cases. In the RUA group, 96%, 72% and 100% of cases showed normal expression patterns with CK20, Ki-67 and E-Cad, respectively. Of 28% RUA cases with increased Ki-67, none demonstrated abnormal CK20 or E-Cad expression. In the AUS group, 47% demonstrated abnormal CK20 and increased Ki-67 expression, suggestive of urothelial dysplasia/CIS, 29% were negative with both, suggestive of RUA, and the remaining 24% cases could not be resolved. In summary, abnormal CK20 is a useful adjunct to morphology for confirming dysplasia. Ki-67 by itself is a less reliable marker of dysplasia. E-Cad is not a useful marker in this setting.

Biomarkers, Tumor↗

CXCL12 overexpression and secretion by aging fibroblasts enhance human prostate epithelial proliferation in vitro.

The direct relationship between the aging process and the incidence and prevalence of both benign prostatic hyperplasia (BPH) and prostate cancer (PCa) implies that certain risk factors associated with the development of both diseases increase with the aging process. In particular, both diseases share an overly proliferative phenotype, suggesting that mechanisms that normally act to suppress cellular proliferation are disrupted or rendered dysfunctional as a consequence of the aging process. We propose that one such mechanism involves changes in the prostate microenvironment, which 'evolves' during the aging process and disrupts paracrine interactions between epithelial and associated stromal fibroblasts. We show that stromal fibroblasts isolated from the prostates of men 63-81 years of age at the time of surgery express and secrete higher levels of the CXCL12 chemokine compared with those isolated from younger men, and stimulate CXCR4-mediated signaling pathways that induce cellular proliferation. These studies represent an important first step towards a mechanistic elucidation of the role of aging in the etiology of benign and malignant prostatic diseases.

Aged↗