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C S Cooper

Publications and source records attributed to C S Cooper.

At least 19 recordsLinked to original sources
PubMed2006

Diversity of TMPRSS2-ERG fusion transcripts in the human prostate.

TMPRSS2-ERG gene fusions have recently been reported to be present in a high proportion of human prostate cancers. In the current study, we show that great diversity exists in the precise structure of TMPRSS2-ERG hybrid transcripts found in human prostates. Fourteen distinct hybrid transcripts are characterized, each containing different combinations of sequences from the TMPRSS2 and ERG genes. The transcripts include two that are predicted to encode a normal full-length ERG protein, six that encode N-terminal truncated ERG proteins and one that encodes a TMPRSS2-ERG fusion protein. Interestingly, distinct patterns of hybrid transcripts were found in samples taken from separate regions of individual cancer-containing prostates, suggesting that TMPRSS2-ERG gene fusions may be arising independently in different regions of a single prostate.

Gene Expression Regulation, Neoplastic↗
PubMed2006

Role of E2F3 expression in modulating cellular proliferation rate in human bladder and prostate cancer cells.

Amplification and overexpression of the E2F3 gene at 6p22 in human bladder cancer is associated with increased tumour stage, grade and proliferation index, and in prostate cancer E2F3 overexpression is linked to tumour aggressiveness. We first used small interfering RNA technology to confirm the potential importance of E2F3 overexpression in bladder cancer development. Knockdown of E2F3 expression in bladder cells containing the 6p22 amplicon strongly reduced the extent of bromodeoxyuridine (BrdU) incorporation and the rate of cellular proliferation. In contrast, knockdown of CDKAL1/FLJ20342, another proposed oncogene, from this amplicon had no effect. Expression cDNA microarray analysis on bladder cancer cells following E2F3 knockdown was then used to identify genes regulated by E2F3, leading to the identification of known E2F3 targets such as Cyclin A and CDC2 and novel targets including pituitary tumour transforming gene 1, Polo-like kinase 1 (PLK1) and Caveolin-2. For both bladder and prostate cancer, we have proposed that E2F3 protein overexpression may cooperate with removal of the E2F inhibitor retinoblastoma tumor suppressor protein (pRB) to drive cellular proliferation. In support of this model, we found that ectopic expression of E2F3a enhanced the BrdU incorporation, a marker of cellular proliferation rate, of prostate cancer DU145 cells, which lack pRB, but had no effect on the proliferation rate of PC3 prostate cancer cells that express wild-type pRB. BrdU incorporation in PC3 cells could, however, be increased by overexpressing E2F3a in cells depleted of pRB. When taken together, these observations indicate that E2F3 levels have a critical role in modifying cellular proliferation rate in human bladder and prostate cancer.

Cell Line, Tumor↗
PubMed2005

Construction of tissue microarrays from prostate needle biopsy specimens.

Needle biopsies are taken as standard diagnostic specimens for many cancers, but no technique exists for the high-throughput analysis of multiple individual immunohistochemical (IHC) markers using these samples. Here we present a simple and highly reliable technique for constructing tissue microarrays (TMAs) from prostatic needle biopsies. Serial sectioning of the TMAs, called 'Checkerboard TMAs', facilitated expression analysis of multiple proteins using IHC markers. In total, 100% of the analysed biopsies within the TMA both preserved their antigenicity and maintained their morphology. Checkerboard TMAs will allow the use of needle biopsies (i) alongside other tissue specimens (trans-urethral resection of prostates and prostatectomies in the case of prostate cancer) in clinical correlation studies when searching for new prognostic markers, and (ii) in a diagnostic context for assessing expression of multiple proteins in cancers from patients prior to treatment.

Biopsy, Needle↗
PubMed2005

Expression analysis onto microarrays of randomly selected cDNA clones highlights HOXB13 as a marker of human prostate cancer.

In a strategy aimed at identifying novel markers of human prostate cancer, we performed expression analysis using microarrays of clones randomly selected from a cDNA library prepared from the LNCaP prostate cancer cell line. Comparisons of expression profiles in primary human prostate cancer, adjacent normal prostate tissue, and a selection of other (nonprostate) normal human tissues, led to the identification of a set of clones that were judged as the best candidate markers of normal and/or malignant prostate tissue. DNA sequencing of the selected clones revealed that they included 10 genes that had previously been established as prostate markers: NKX3.1, KLK2, KLK3 (PSA), FOLH1 (PSMA), STEAP2, PSGR, PRAC, RDH11, Prostein and FASN. Following analysis of the expression patterns of all selected and sequenced genes through interrogation of SAGE databases, a further three genes from our clone set, HOXB13, SPON2 and NCAM2, emerged as additional candidate markers of human prostate cancer. Quantitative RT-PCR demonstrated the specificity of expression of HOXB13 in prostate tissue and revealed its ubiquitous expression in a series of 37 primary prostate cancers and 20 normal prostates. These results demonstrate the utility of this expression-microarray approach in hunting for new markers of individual human cancer types.

Biomarkers, Tumor↗
PubMed2005

Processing of radical prostatectomy specimens for correlation of data from histopathological, molecular biological, and radiological studies: a new whole organ technique.

AIMS: To develop a method of processing non-formalin fixed prostate specimens removed at radical prostatectomy to obtain fresh tissue for research and for correlating diagnostic and molecular results with preoperative imaging. METHODS/RESULTS: The method involves a prostate slicing apparatus comprising a tissue slicer with a series of juxtaposed planar stainless steel blades linked to a support, and a cradle adapted to grip the tissue sample and receive the blades. The fresh prostate gland is held in the cradle and the blades are moved through the cradle slits to produce multiple 4 mm slices of the gland in a plane perpendicular to its posterior surface. One of the resulting slices is preserved in RNAlater. The areas comprising tumour and normal glands within this preserved slice can be identified by matching it to the haematoxylin and eosin stained sections of the adjacent slices that are formalin fixed and paraffin wax embedded. Intact RNA can be extracted from the identified tumour and normal glands within the RNAlater preserved slice. Preoperative imaging studies are acquired with the angulation of axial images chosen to be similar to the slicing axis, such that stained sections from the formalin fixed, paraffin wax embedded slices match their counterparts on imaging. CONCLUSIONS: A novel method of sampling fresh prostate removed at radical prostatectomy that allows tissue samples to be used both for diagnosis and molecular analysis is described. This method also allows the integration of preoperative imaging data with histopathological and molecular data obtained from the prostate tissue slices.

Biomedical Research↗
PubMed2003

Expression profile of genes from 12p in testicular germ cell tumors of adolescents and adults associated with i(12p) and amplification at 12p11.2-p12.1.

Gain of 12p material is invariably associated with testicular germ cell tumors (TGCTs) of adolescents and adults, most usually as an isochromosome 12p. We analyzed TGCTs with i(12p) using a global approach to expression profiling targeting chromosomes (comparative expressed sequence hybridization, CESH). This indicated overexpression of genes from 12p11.2-p12.1 relative to testis tissue and fibroblasts. The nonseminoma subtype showed higher levels of expression than seminomas. Notably, 12p11.2-p12.1 is amplified in about 10% of TGCTs and CESH analysis of such amplicon cases showed high levels of overexpression from this region. Microarray analysis, including cDNA clones representing most UniGene clusters from 12p11.2-p12.1, was applied to DNA and RNA from 5 TGCTs with amplification of 12p11.2-p12.1 and seven TGCTs with gain of the entire short arm of chromosome 12. Expression profiles were consistent with the CESH data and overexpression of EST595078, MRPS35 and LDHB at 12p11.2-p12.1 was detected in most TGCTs. High-level overexpression of BCAT1 was specific to nonseminomas and overexpression of genes such as CMAS, EKI1, KRAS2, SURB7 and various ESTs correlated with their amplification. Genes such as CCND2, GLU3, LRP6 and HPH1 at 12p13 were also overexpressed. The overexpressed sequences identified, particularly those in the region amplified, represent candidate genes for involvement in TGCT development.

Adolescent↗
PubMed2003

Molecular classification of synovial sarcomas, leiomyosarcomas and malignant fibrous histiocytomas by gene expression profiling.

In this study, we have used genome-wide expression profiling to categorise synovial sarcomas, leiomyosarcomas and malignant fibrous histiocytomas (MFHs). Following hierarchical clustering analysis of the expression data, the best match between tumour clusters and conventional diagnosis was observed for synovial sarcomas. Eight of nine synovial sarcomas examined formed a cluster that was characterised by higher expression of a set of 48 genes. In contrast, sarcomas conventionally classified as leiomyosarcomas and MFHs did not match the clusters defined by hierarchical clustering analysis. One major cluster contained a mixture of both leiomyosarcomas and MFHs and was defined by the lower expression of a set of 202 genes. A cluster containing a subgroup of MFHs was also detected. These results may have implications for the classification of soft tissue sarcomas, and are consistent with the view that sarcomas conventionally defined as MFHs do not represent a separate diagnostic category.

Cluster Analysis↗
PubMed2001

Applications of microarray technology in breast cancer research.

Microarrays provide a versatile platform for utilizing information from the Human Genome Project to benefit human health. This article reviews the ways in which microarray technology may be used in breast cancer research. Its diverse applications include monitoring chromosome gains and losses, tumour classification, drug discovery and development, DNA resequencing, mutation detection and investigating the mechanism of tumour development.

Breast Neoplasms↗
PubMed2001

PRCC, the commonest TFE3 fusion partner in papillary renal carcinoma is associated with pre-mRNA splicing factors.

In papillary renal cell carcinomas the TFE3 transcription factor becomes fused to the PSF and NonO pre-mRNA splicing factors and most commonly to a protein of unknown function designated PRCC. In this study we have examined the ability of the resulting PRCC-TFE3 and NonO-TFE3 fusions to activate transcription from the plasminogen activator inhibitor-1 (PAI-1) promoter. The results show that only fusion to PRCC enhanced transcriptional activation, indicating that the ability to enhance the level of transcription from endogenous TFE3 promoters is not a consistent feature of TFE3 fusions. In investigations of the normal function of PRCC we observed that PRCC expressed as a green fluorescent fusion protein colocalizes within the nucleus with Sm pre-mRNA splicing factors. It was also found that endogenous PRCC is coimmunoprecipitated by antibodies that recognize a variety of pre-mRNA splicing factors including SC35, PRL1 and CDC5. Association with the cellular splicing machinery is therefore, a common feature of the proteins that become fused to TFE3 in papillary renal cell carcinomas.

Adult↗
PubMed2001

Optimal solder and power density for diode laser tissue soldering (LTS).

BACKGROUND AND OBJECTIVE: Laser tissue soldering (LTS) using albumin and indocyanine green dye (ICG) is an effective technique utilized in various reconstructive surgical procedures. The purpose of this study was to describe in vivo and in vitro temperature profiles of an albumin-based solder while varying ICG concentration and laser power density (PD), and to describe immediate and short-term tensile strength measurements and histology of tissue with variable ICG concentrations and PD. STUDY DESIGN/MATERIALS AND METHODS: ICG ranged from 0.31 to 20 mg/mL while PD ranged from 3.2 to 63.7 W/cm(2). Direct solder temperature measurements were obtained at 5-second intervals during laser activation. Differential temperature measurements were determined within the dermis of rat skin and the overlying solder. Eighteen rats were subjected to 2.0-cm incisions (n = 113) created on the dorsal skin followed by closure with LTS at varying PD and ICG concentrations. ICG concentrations included 0.31, 2.5, and 20 mg/mL, while PD ranged from 8.0 to 63.7 W/cm(2). Tensile strength (TS) profiles were measured immediately and 10 days post-operatively. Histological examination was performed at the time of sacrifice. RESULTS: Temperature profiles of the ICG/albumin solder differed significantly only at the highest concentration of ICG (20 mg/mL), but showed statistically significant variability at different laser PD. Using solder color changes as an endpoint of LTS, average peak solder temperature ranged from 69 degrees C at a PD of 8.0 W/cm(2), 105 degrees -120 degrees C at PD 15.9-31.8 W/cm(2), and > 200 degrees C at PD > or = 47.7 W/cm(2). Peak intradermal temperatures remained below 50 degrees C at all PDs. Varying ICG concentration only had an effect on the immediate TS of wounds at the lowest power densities. Increasing PD resulted in statistically significant increases in immediate TS up to a PD of 23.9 W/cm(2) at an ICG concentrations of 0.31 and up to a PD of 15.9 W/cm(2) at a concentration of 2.5 mg/mL. Statistically insignificant decreases in 10-day would strength resulted from higher PD. Power densities > or = 23.9 W/cm(2) showed significant thermal injury upon histologic examination. CONCLUSIONS: Power density, not ICG concentration, is the primary determinant of solder and tissue temperature during LTS. Effective and reproducible laser tissue soldering may be achieved primarily by power density control when using diode laser and ICG-based albumin solder. Alterations in PD show the most direct and predictable effects on the healing properties of skin closed by LTS. Optimal laser wound closure occurs with an ICG of 2.5 mg/mL and at a PD between 15.9 and 23.9 W/cm(2).

Albumins↗
PubMed2001

Application of the Cecil-Culp repair for treatment of urethrocutaneous fistulas after hypospadias surgery.

OBJECTIVES: To present our technique and results using a modification of the Cecil-Culp technique of hypospadias repair in a select group of boys with urethrocutaneous fistula during a 6-year period. Urethrocutaneous fistula remains the most common complication of hypospadias repair. Coverage of suture lines with vascularized tissue is thought to decrease fistula formation. METHODS: Between 1994 and 1999, 15 boys with hypospadias fistula underwent repair with a modified two-stage Cecil technique. The records were reviewed with respect to age, type of original hypospadias repair, number of previous fistulas, location of the fistulas, and complications. RESULTS: The average age at the time of the first stage of fistula repair was 3.5 years (range 1.8 to 6.0). Five, four, and two patients had undergone one, two, and three previous fistula repairs, respectively. Four boys in this series had deficient penile skin at the time of their first fistula repair. Most had one fistula at the time of the Cecil repair, including eight at the corona, four along the penile shaft, and three in a more proximal location. No patients had a recurrent fistula, with an average follow-up of 21 months (range 1 to 62). CONCLUSIONS: Boys with recurrent fistula, despite previous fistula repair, and deficient penile skin present a technical reconstructive challenge. The modified Cecil technique for fistula repair takes advantage of penile mobility to place it in a scrotal location, ensuring excellent vascularized tissue coverage. Although this technique requires a brief second-stage operation, no recurrent fistula has occurred in any of our patients.

Child↗
PubMed2001

Preservation of urethral plate spongiosum: technique to reduce hypospadias fistulas.

OBJECTIVES: Fistula remains the most common complication of hypospadias repair. Buried and well-vascularized suture lines reduce the incidence of fistula. We review the results of routine preservation and incorporation of the abortive spongiosum to prevent fistulas with the onlay island flap technique of hypospadias repair. METHODS: Thirty-six consecutive boys underwent hypospadias repair with an onlay island flap during a 2-year period, with preservation and incorporation of the abortive spongiosum. The technique of using the abortive spongiosum in these children was reviewed. The age at surgery, preoperative meatal position, chordee presence, and neourethral length was noted. RESULTS: The average age at surgery was 13.1 +/- 18.5 months, with an average follow-up of 15.4 +/- 6.7 months. The preoperative meatal position was midshaft in 15 boys, more proximal in 14, and more distal in 7 boys. Four boys required dorsal plication because of persistent chordee after skin takedown. The average neourethral length created with the onlay flap was 16.8 +/- 7.6 mm. Complications occurred in 5 patients and included three diverticulae, one urinary tract infection, and one glanular adhesion. No fistula occurred in any patient. CONCLUSIONS: The abortive spongiosum is routinely obtainable with careful penile degloving. This technique provides a vascular tissue for coverage of the suture lines and reduces fistula formation.

Follow-Up Studies↗
PubMed2001

Laser tissue soldering for hypospadias repair: results of a controlled prospective clinical trial.

PURPOSE: Laser tissue soldering has been shown to provide safe and effective tissue closure by creating an immediate leak-free anastomosis with minimal scar formation. We compared the results of laser tissue soldering and conventional suturing for hypospadias repair. MATERIALS AND METHODS: A consecutive group of 138 boys 4 months to 8 years old (mean age 15 months) was divided into a standard suturing (84) and a sutureless laser (54) hypospadias repair group. Urethral repair was defined as simple (Thiersch-Duplay or Snodgrass) and complex (onlay island flap or tube) in 101 and 37 cases, respectively. Laser tissue soldering was performed with 50% human albumin solder doped with 2.5 mg./ml. indocyanine green dye using an 808 nm. diode laser at 0.5 W. In the laser group sutures were used for tissue alignment only. At surgery neourethral and penile length, operative time for neourethral construction and the number of sutures or throws were measured. Postoperatively patients were examined for complications of wound healing, stricture or fistula. RESULTS: Mean patient age, urethral defect severity, type of repair, neourethral length and stenting time plus or minus standard error of mean were not significantly different in the 2 groups. Mean operative time was a fifth as long for laser tissue soldering in simple and complex hypospadias repair compared to controls (1.5 +/- 0.1 and 5.1 +/- 0.3 versus 8.5 +/- 0.8 and 26.7 +/- 1.7 minutes, respectively, p <0.001). The mean number of sutures used for tissue alignment in the laser group for simple and complex repair was significantly less than in controls (3.0 +/- 0.2 and 8.2 +/- 0.6 versus 8.5 +/- 0.8 and 23.2 +/- 1.5, respectively, p <0.001). All patients were followed a mean of 12 months (minimum 6, maximum 22). The complication rate was 4.7% in the laser group and 10.7% in controls with fistula in 2 of 54 cases, and fistula and meatal stenosis in 7 and 2 of 84, respectively. CONCLUSIONS: These preliminary results indicate that laser tissue soldering for hypospadias repair may be performed in almost sutureless fashion and more rapidly than conventional suturing. The ease of the laser technique and the lower complication rate in the laser group indicate that laser tissue soldering is an acceptable means of tissue closure in hypospadias repair.

Child↗
PubMed2001

Intravesical Jackson-Pratt drain for urinary diversion after augmentation cystoplasty.

PURPOSE: Augmentation cystoplasty has become a primary form of bladder management in children with a noncompliant bladder. Excellent urinary drainage is required for anastomotic healing and the removal of mucous buildup. Suprapubic drainage traditionally involves a Malecot catheter, although poor irrigation and dislodgment of this type of catheter are well-known complications. We report the placement of an intravesical Jackson-Pratt drain for urinary diversion in augmented bladders. MATERIALS AND METHODS: We reviewed our use of an intravesical Jackson-Pratt drain for urinary diversion between 1995 and 1999 in 17 patients. Postoperative catheter drainage and irrigation characteristics were assessed as well as catheter related complications. RESULTS: Average patient age was 13 years (range 3 to 27). The majority of patients underwent ileal (11) or sigmoid (4) cystoplasty and 1 each underwent composite and ureteral cystoplasty. Drains remained in place an average of 27 days (range 6 to 57). All patients had excellent drainage during the postoperative period. Irrigation was subjectively easier than with a Malecot catheter. Average cost of a latex-free Malecot catheter was 2.7-fold that of a Jackson-Pratt drain. No catheters became nonfunctional before removal, although 1 was inadvertently pulled during patient transfer. CONCLUSIONS: A Jackson-Pratt drain provides excellent urinary drainage in patients undergoing augmentation cystoplasty. Multiple openings along the tube seem to improve irrigation in contrast to the single opening in a Malecot catheter, which often aspirates a region of the augmented bladder. The ready availability, decreased cost, ease of irrigation, increased pliability with decreased chance of dislodgment and lack of latex make an intravesical Jackson-Pratt drain a superior choice for augmented neurogenic bladder.

Adolescent↗
PubMed2001

The use of vesicostomy as permanent urinary diversion in the child with myelomeningocele.

PURPOSE: Treatment of the child with myelomeningocele presents the urologist with many challenges. While vesicostomies are usually used for temporary bladder drainage until continent reconstruction is performed, we have a population of postpubertal patients with myelomeningocele in whom vesicostomies have been preserved. We review our experience with these older children. MATERIALS AND METHODS: A search of our database of 350 patients with myelodysplasia identified 23 with urinary diversion accomplished by permanent vesicostomy. Those who had undergone vesicostomy after age 11 years were designated as group 1. Those who received a vesicostomy early in life that was maintained post puberty were designated as group 2. Indications for vesicostomy, upper tract status before and after vesicostomy, recurrent infections and complications were noted. Upper tract status was determined by serial ultrasounds during routine followup. RESULTS: Group 1 was comprised of 5 patients with mean age at vesicostomy of 17 years and a mean followup interval of 5.2 years. Group 2 was comprised of 18 patients with mean age of vesicostomy at 2.6 years and mean followup interval of 13 years. Hydronephrosis resolved in all children from both groups. Vesicostomy revision was required in 1 patient secondary to prolapse. Other complications included mild prolapse that did not require revision, stenosis requiring revision 5 months after the initial procedure and an early bilateral ureterovesical obstruction that resolved. Of the patients 33% had recurrent upper tract calculi. CONCLUSIONS: While the goal of achieving urinary continence is well worth striving for in the child with myelomeningocele, it is not realistic for all patients. We believe that permanent cutaneous vesicostomy is an acceptable alternative that the reconstructive surgeon should consider. This reliable and simple technique ensures safe decompression of the upper urinary tracts, while avoiding the complications of urinary diversion using segments of bowel.

Adolescent↗
PubMed2000

LUCA-15-encoded sequence variants regulate CD95-mediated apoptosis.

Using an expression cloning system to discover novel genes involved in apoptosis, we identified a 326 bp bone marrow cDNA fragment (termed Je2) that suppresses, upon transfection, CD95-mediated apoptosis in Jurkat T cells. Sequence homology revealed that Je2 maps to 3p21.3, to an intronic region of the candidate TSG LUCA-15 locus. It represents, in fact, an antisense transcript to the 3'-UTR of two novel splice variants of this gene. Overexpression of sequence representing one of these splice variants (a 2.6 kb cDNA termed Clone 26), inhibited proliferation of Jurkat cells and sensitized them to CD95-mediated apoptosis. This study therefore implicates the LUCA-15 gene locus in the control of apoptosis.

Alternative Splicing↗
PubMed2000

Appendicovesicostomy: the mitrofanoff procedure-a 15-year perspective.

PURPOSE: Appendicovesicostomy was introduced in the United States in 1982 at our hospital. It has become the most popular alternate continence channel for catheterization. We reviewed the experience of 1 surgeon with appendicovesicostomy during a 15-year period. MATERIALS AND METHODS: We retrospectively reviewed the operative reports and clinical records of 50 consecutive patients in whom appendicovesicostomy was performed by 1 surgeon between 1982 and 1998. The underlying diagnosis was myelomeningocele in 31 cases, bladder exstrophy in 6, the prune-belly syndrome in 2, posterior urethral valves in 2 and other disorders in 10. Mean patient age at surgery was 13.1 years (range 4 months to 25 years) and mean followup was 4.3 years (range 3 months to 16.3 years). RESULTS: Of the 50 patients 96% continue to catheterize the appendicovesicostomy. Stomal stenosis developed in 5 cases (10%) and other complications included stricture and appendiceal perforation in 2 each. Eight patients (16%) required appendicovesicostomy revision at a median of 7.3 months (range 1 month to 5.8 years) after the initial procedure. Median time to revision for stomal stenosis was 13 months (range 1 month to 5.8 years). Appendicovesicostomy continence was achieved in 49 patients (98%). CONCLUSIONS: Our series demonstrates the successful long-term outcome and durability of appendicovesicostomy in children. Careful adherence to technique at initial surgery helps ensure a high long-term success rate.

Adolescent↗