Androgen responsive adult human prostatic epithelial cell lines immortalized by human papillomavirus 18.

Prostate cancer and benign tumors of the prostate are the two most common neoplastic diseases in men in the United States, however, research on their causes and treatment has been slow because of the difficulty in obtaining fresh samples of human tissue and a lack of well characterized cell lines which exhibit growth and differentiation characteristics of normal prostatic epithelium. Non-neoplastic adult human prostatic epithelial cells from a white male donor were immortalized with human papillomavirus 18 which resulted in the establishment of the RWPE-1 cell line. Cells from the RWPE-1 cell line were further transformed by v-Ki-ras to establish the RWPE-2 cell line. The objectives of this study were to: (1) establish the prostatic epithelial origin and androgen responsiveness of RWPE-1 and RWPE-2 cell lines; (2) examine their response to growth factors; and (3) establish the malignant characteristics of the RWPE-2 cell line. Immunoperoxidase staining showed that both RWPE-1 and RWPE-2 cells express cytokeratins 8 and 18, which are characteristic of luminal prostatic epithelial cells, but they also coexpress basal cell cytokeratins. These cell lines show growth stimulation and prostate specific antigen (PSA) and androgen receptor (AR) expression in response to the synthetic androgen mibolerone, which establishes their prostatic epithelial origin. Both cell lines also show a dose-dependent growth stimulation by EGF and bFGF and growth inhibition when exposed to TGF-beta, however, the transformed RWPE-2 cells are less responsive. RWPE-1 cells neither grow in agar nor form tumors when injected into nude mice with or without Matrigel. However, RWPE-2 cells form colonies in agar and tumors in nude mice. In the in vitro invasion assay, RWPE-1 cells are not invasive whereas RWPE-2 cells are invasive. Nuclear expression of p53 and Rb proteins was heterogeneous but detectable by immunostaining in both cell lines. The RWPE-1 cells, which show many normal cell characteristics, and the malignant RWPE-2 cells, provide useful cell culture models for studies on prostate growth regulation and carcinogenesis.

Prostate specific antigen and androgen receptor induction and characterization of an immortalized adult human prostatic epithelial cell line.

Progress in prostate cancer research has been hindered by the lack of well characterized, immortalized, human prostatic epithelial cell lines that express markers of normal prostatic epithelial cells and mimic normal growth and differentiation responses to androgens. The objectives of this study were to: (i) establish immortalized cell lines from non-neoplastic, adult human prostatic epithelium using adenovirus-12/simian virus-40 (Ad12-SV40) hybrid virus; (ii) establish their prostatic epithelial origin; (iii) demonstrate androgen responsiveness; and (iv) examine response to growth factors. Primary epithelial cell cultures derived from a non-neoplastic, adult human prostate were infected with the Ad12-SV40 virus. Several immortalized clones were isolated. Single cell cloning of one clone, free of cytopathic effects, gave rise to the PWr-1E cell line. An immortalized cell line PWR-1E, which expresses many characteristics of normal prostatic epithelial cells was established. Immunostaining showed that cells express cytokeratins 8 and 18 normally expressed by differentiated, secretory prostatic epithelial cells. The most remarkable characteristics of PWR-1E cells are growth stimulation, increased expression of androgen receptor and induction of prostate specific antigen (PSA) expression in response to androgens, which indisputably establish their prostatic epithelial origin. They are positive for SV40 large-T antigen and show strong nuclear staining for p53. Cells from passages 23 and 40 were not tumorigenic in nude mice even when co-injected with Matrigel. They grow in a serum-free defined medium and respond to EGF, bFGF and TGF-beta. Passage 42-cells showed a human male (XY), hyperdiploid karyotype. The PWR-1E cell line is the only known Ad12-SV40-immortalized human prostatic epithelial cell line. PWR-1E cells can be used to study (i) the etiology and the multistep process of carcinogenesis and tumor progression in the human prostate; (ii) normal prostate physiology and differentiation; and (iii) potential prostate cancer chemopreventive agents.

Bacillus Calmette-Guerin therapy for superficial bladder cancer: a 10-year followup.

We report the outcome of 61 patients with superficial bladder tumors who received bacillus Calmette-Guerin (BCG) therapy and were followed for at least 10 years (range 10 to 13 years). A total of 19 patients (31%) remains free of tumor and progression, 17 (28%) had interval superficial recurrences but no progression and 25 (41%) had progression, first identified as muscle invasion in 12, prostatic involvement in 8 or metastasis in 5. Most tumors recurred or progressed within the first 5 years. Of the 61 patients 33 (54%) are disease-free and with an intact bladder, 13 (21%) are alive after cystectomy, 2 (3%) died of other causes, 1 (2%) is alive with metastasis and 12 (20%) died of metastatic urothelial cancer (11 from the bladder or prostate and 1 from an upper tract tumor).

Immunopathologic analysis of human urinary bladder cancer. Characterization of two new antigens associated with low-grade superficial bladder tumors.

The authors have further characterized the normal human tissue distribution and tumor expression of two highly restricted tumor-associated antigens, detected by mouse monoclonal antibodies M344 and 19A211, which are primarily expressed on low-grade superficial urinary bladder tumors. This study was conducted using immunohistochemical staining of frozen and deparaffinized sections of human normal and tumor tissues. The antigens are stable and well preserved on deparaffinized tissue sections. M344 antibody identifies a high-molecular-weight determinant on a cytosolic protein component of over 300,000 Mr. This antigen was not detected on any normal tissue analyzed, including 14 specimens of normal urothelium and 22 cases of cystitis; however, M344 was positive in 74.5% of Ta-T1 tumors and 11% of T3-T4 tumors. 19A211 antibody identifies a sialylated epitope on a cytoplasmic protein complex of 100,000 to 200,000 Mr. This antigen also was expressed preferentially on low-grade superficial bladder tumors (77% Ta-T1) and less frequently on deeply infiltrating tumors (10% T3-4). 19A211 was negative on all normal cells tested, with the exception of umbrella cells, in approximately 25% of the normal urothelium and cystitis specimens studied. Either one or both of these tumor-associated antigens are detected in approximately 80% of low-grade papillary superficial tumors and carcinoma in situ of the urinary bladder. The expression of these antigens on a subset of low-grade bladder tumors, known to progress in only about 10% of cases, suggests that phenotypic differences may reflect biologic potential. Beyond their possible biologic significance, antibodies M344 and 19A211 may provide clinically useful probes for early detection and stratification of urinary bladder tumors.

DNA, RNA and immunohistochemical characterization of the HER-2/neu oncogene in transitional cell carcinoma of the bladder.

HER-2/neu overexpression appears to play a role in determining the malignant potential of some human cancers. To date, no urothelial malignancies appear to have been evaluated for HER-2/neu DNA amplification, mRNA expression and protein overproduction. By Southern hybridization we detected DNA amplification and a possible structural rearrangement of the HER-2/neu oncogene in one of 12 bladder tumors. A 14 kb DNA fragment in addition to the expected 12.5 Kb fragment was found. Additionally, the HER-2/neu oncogene was amplified sixfold in the tumor compared to placental DNA. Five of 14 (36%) bladder tumors overexpressed HER-2/neu mRNA three to 38-fold compared to normal urothelium. HER-2/neu overexpression occurred in superficial and invasive tumors. Immunohistochemical analysis was performed on the one tumor with DNA amplification and the 14 tumors evaluated for mRNA expression. The tumor with DNA amplification and three of the five tumors with HER-2/neu mRNA overexpression stained positively for the p185HER-2/neu protein. These findings suggest that DNA amplification occurs infrequently in bladder cancer. Thirty-six percent of bladder cancers overexpress HER-2/neu mRNA. Immunohistochemical analysis with a p185HER-2/neu polyclonal antibody, on formalin fixed, paraffin embedded tissue, was specific for HER-2/neu overexpression but not as sensitive as Northern analysis.

Association of type 1 blood group antigens with urinary tract infections in children with genitourinary structural abnormalities.

Bacterial adherence to carbohydrate receptors on the surface of urothelial cells is important in the pathogenesis of urinary tract infections. Blood group-related antigens, genetically determined carbohydrate structures found on the urothelial cell surface, may influence the availability of these receptors thereby affecting bacterial adherence and the susceptibility to urinary tract infections. Recent evidence indicates that the immunoanatomical distribution of type 1 blood group-related antigens in urothelium is influenced by ABO, Lewis and secretor phenotypes, women with Le(a-b-) and Le(a+b-) blood phenotypes have more than a 3-fold greater risk of recurrent urinary tract infections compared to Le(a-b+) women and epithelial cells from nonsecretors have more bacterial receptors than cells from secretors. To determine the relation between the expression of type 1 blood group-related antigens and urinary tract infections we performed an immunohistochemical analysis using a well characterized panel of monoclonal antibodies on 72 surgical specimens obtained from children who underwent correction of a structural genitourinary anomaly at the University of Rochester Medical Center from December 1983 to May 1988. Of 72 children 48 had a history of at least 1 documented urinary tract infection. The differences in the distribution of children by type 1 blood group immunophenotype in the infection and noninfection groups were highly significant (p = 0.003, Fisher's exact test). There is an increased frequency of urinary tract infections in children with genitourinary structural anomalies whose urothelium reflects the nonsecretor phenotype, that is they have minimal or undetectable levels of ABO and Leb reactivity compared to those with intense ABO and/or Leb immunoreactivity. Of 17 children with minimal or no ABO or Leb immunoreactivity 16 (94.1%) belonged to the infection group. Furthermore, 23 of 24 patients (95.8%) without a history of urinary tract infection expressed intense ABO and/or Leb immunoreactivity. It appears that the type 1 blood group-related antigen profile of urothelium influences susceptibility to urinary tract infection and it may be important in identifying patients who would benefit from prophylactic antibiotic therapy or earlier surgical intervention.