Lowered amounts of the tissue-specific transcription factor LFB1 (HNF1) correlate with decreased levels of glutathione S-transferase alpha messenger RNA in human renal cell carcinoma

Human renal cell carcinoma is characterized by the loss of differentiation markers such as glutathione S-transferase alpha (GST-alpha). In this paper we show that the promoter of a GST-alpha gene contains a functional binding site for the cell-specific transcription factor LFB1 (HNF1). To investigate the potential role of LFB1 in the down-regulation of GST-alpha expression, we have compared the amount and the binding activity of the LFB1 protein between normal kidney and tumor tissue. By Western analysis and gel retardation assay using a monoclonal antibody specific for LFB1 we show that in 11 of 14 carcinomas the amount of LFB1 is clearly reduced compared to the corresponding normal tissue and that in all 14 renal carcinomas LFB1 binding activity is diminished. As in the same samples the abundance of GST-alpha mRNA is lower than in the normal tissue, we postulate that the loss of LFB1 binding activity might be responsible for the decreased expression of the GST-alpha gene in renal cell carcinoma.

Expression of NAD(P)H:quinone oxidoreductase and glutathione S-transferases alpha and pi in human renal cell carcinoma and in kidney cancer-derived cell lines

NAD(P)H:quinone oxidoreductase (NQOR) and glutathione S-transferases (GST) are enzymes of interest in cell defence and drug resistance. Relative levels of NQOR mRNA in renal cell carcinomas were 28 +/- 24% (n = 21) of those in non-neoplastic tissue and the enzyme activity decreased from 41 +/- 39 to 18 +/- 27 mU/mg protein (n = 23). In three of the cases, there was no measurable NQOR enzyme activity at all, indicating a polymorphism in the population for this gene. Relative GST-alpha mRNA levels in the tumours were on average 6 +/- 6% (n = 22) of the control value, whereas for GST-pi mRNA smaller decreases as well as increases were found in the tumours as compared to control tissue, but, on average, the level remained unchanged. Overall GST activity measured with CDNB as a substrate was 152 +/- 157 mU/mg protein in tumour tissue and 342 +/- 177 mU/mg protein in non-neoplastic tissue (n = 23). In all kidney tumour-derived cell lines NQOR mRNA was strongly expressed and on a per protein basis NQOR activity was about 10-fold higher than in the kidney tumour samples. GST-pi but not GST-alpha mRNA was also present. Total GST enzyme activities in these cell lines were similar to those in kidney tumour samples. HepG2 cells exhibited expression of NQOR and GST-alpha; GST-pi was not detectable. NQOR activity in HepG2 was about four-fold higher than in kidney-derived cell lines. Thus, NQOR and GST-alpha are both down-regulated in renal carcinoma, but their expression diverges in carcinoma cell lines.

[Immunotherapy of superficial bladder cancer]

Because patients with superficial bladder cancer are in a high-risk group where tumor progression is concerned, topical therapeutic strategies are necessary to prevent tumor recurrence and tumor progression. Based on experimental studies and several case reports, during the last two decades immunotherapy for superficial bladder cancer has been developed. The effects of topical instillation of bacillus Calmette-Guerin (BCG) has been carefully investigated in numerous clinical trials. Especially patients with carcinoma in situ appear to benefit from BCG therapy. Other types of local immunotherapy, e.g., instillation of interferons, interleukins, and keyhole limpet hemocyanin have been found to have fewer side effects than BDG. These new approaches are currently under clinical investigation.

[A study of the quantitative dual-parameter flow cytometry analyses of cellular antigens on transitional cells for the diagnosis of bladder cancer]

To establish a quantitative dual-parameter flow cytometry (FCM) analysis of cell surface antigens, possible obstacles caused by contaminated leucocytes in a specimen and staining and measuring conditions were investigated using human bladder cancer cell lines, 5637, T24 and SW1710. The first monoclonal antibody (MoAb) used to select urothelial cells in a specimen was applied with the second MoAb used to discriminate between normal and transformed urothelial cells. MoAbs Due AUT 2 and CD45 appeared to be suitable for the selection of urothelial cells, while Due ABC 3 and Due ABC 5 were applied to detect transformed cells. Tumor cell-leucocyte suspension was simultaneously stained with combinations of these MoAbs. The results demonstrated that Due AUT 2 and CD45 effectively eliminated contaminated leucocytes by means of positive and negative selection of the urothelial cells, respectively. Based on these experiments, dual-parameter FCM analyses of bladder washing from 5 patients with bladder cancer were performed using MoAbs Due AUT 2 and Due ABC 3. The results indicated that by dual-parameter FCM distinct antigenic features of transitional cells could be investigated even if considerable amounts of contaminated leucocytes were present. The clinical impact of this approach is a subject of ongoing trials.

Monoclonal antibody Due ABC 3 directed against transitional cell carcinoma. I. Production, specificity analysis, and preliminary characterization of the antigen

The development of the hybridoma technology allows the identification of tumor associated antigens with monoclonal antibodies (mAbs). Employing this technology mAb Due ABC 3 was obtained by immunization of a BALB/c mouse with bladder tumor cell line SW 1710 and subsequent cell fusion of spleen cells with P3. X63.Ag8.653 mouse myeloma cells. MAb Due ABC 3, an IgM antibody, was found to recognize an antigen present in the membrane of tumor cells in 25 out of 28 (89%) transitional cell carcinoma specimens but rarely (three out of 25 specimens, 12%) on normal urothelial cells. Cross reactions were seen with proximal tubular epithelium of the kidney and seven out of 12 renal cell carcinomas examined. Furthermore, the antigen was expressed by granulocytes, some gastrointestinal epithelia, ovarian and breast carcinoma. The antigen recognized by mAb Due ABC 3 was stable to fixation with formaldehyde and paraffin emmbedding, different proteases, alkaline treatment and heat exposure up to 70C. Antigenicity was abandoned by incubation with periodate but not with neuraminidase treatment. The antigen could be extracted with chloroform/methanol suggesting the involvement of a glycolipid. Immuno-thin layer chromatography revealed a single lipid band reacting with mAb Due ABC 3 but not with anti-CD15, directed against the Lewis X antigen. Although not tumor-specific, mAbs directed against differentiation antigens may be of value for the investigation of cell transformations as well as for diagnostic use.

Monoclonal antibody Due ABC 3 directed against transitional cell carcinoma. II. Prospective trial on the diagnostic value of immunocytology using monoclonal antibody Due ABC 3

Recently, the development of monoclonal antibody Due ABC 3 directed against transitional cell carcinoma has been reported. With this monoclonal antibody an in vitro test system for diagnosis and followup of patients with transitional cell carcinoma has been developed. The clinical value of this assay, designated as quantitative immunocytology, was evaluated in a prospective trial and compared to conventional cytology. We investigated 74 voided urine specimens obtained from patients with histologically proved transitional cell carcinoma and 60 specimens from donors without clinical evidence of transitional cell carcinoma. Sensitivity was 66% versus 47% for immunocytology and conventional cytology. Specificity of conventional cytology (92%) was higher compared to immunocytology (58%). Statistical analysis demonstrated a significantly higher sensitivity of the combined analysis of conventional cytology and immunocytology (p less than 0.001) compared to conventional cytology alone, without significant differences in specificity. The results obtained with immunocytology were impaired by the great number of nonevaluable specimens. Poor preservation of cells, severe pyuria or an insufficient number of urothelial cells prevented evaluation in 25% of the cases, while only 6% could not be evaluated by conventional cytology. The ability of immunocytology to improve the sensitivity of conventional cytology makes this technique a promising adjunct to the noninvasive diagnosis of transitional cell carcinoma.

Accuracy of imaging modalities in staging the local extent of prostate cancer

In this study, none of the evaluated clinical staging methods was found to predict reliably the presence or absence of extracapsular growth of histologically proved carcinoma of the prostate. In this respect, digital rectal examination, transrectal ultrasound, CT, and MR imaging cannot contribute to treatment decisions in localized prostate cancer. Further studies are under way to determine the value of 7.5-MHz scanners in transrectal ultrasound and high-resolution surface coils in MR imaging.

Assessment of clinical skills of residents utilizing standardized patients. A follow-up study and recommendations for application

OBJECTIVE

To determine the reliability and validity of "standardized patients" to assess clinical performance of internal medicine residents.

DESIGN

Each resident spent 2 half-days interacting with 19 standardized patients (nonphysicians taught to portray patients in a reproducible fashion). Each resident was asked to obtain focused histories, perform relevant physical examinations, and provide patient education or counseling. At the end of each 10- to 15-minute encounter, the resident was asked to identify positive findings on physical examination and to prioritize a differential diagnosis. Other, more traditional indicators of clinical skills were also obtained.

PARTICIPANTS

Three hundred ten residents from nineteen internal medicine training programs in the New England region of the United States.

RESULTS

Reproducible estimates of data gathering and interviewing skills were achieved with 1 day of testing. Validity analyses were difficult to interpret because of the lack of an external "gold standard." However, faculty judgments of performance from reviewing videotapes corresponded with standardized-patient-based scores. Differences in group performance were also demonstrated across years of training and between U.S. or Canadian and foreign medical graduates.

CONCLUSIONS

Systematic and effective procedures for developing standardized-patient-based test materials and for training standardized patients have been developed. This technique is best used for measuring data gathering and interviewing skills. Correlations with commonly used evaluation methods were generally low; this may be because standardized patients measure different skills. Local use of this technique by residency programs and the development of regional consortia sharing resources, costs, and expertise are advocated.

Establishment and characterization of human renal cancer and normal kidney cell lines

We have reviewed our laboratory's efforts to establish continuous human renal cancer cell lines. During the 16-year period of 1972 through 1987, 498 successive attempts resulted in establishment of 63 renal cancer cell lines. Of these lines, 46 were derived from primary kidney tumors and 17 from metastatic sites (lung, brain, bone, and lymph node). Forty-three of these lines have been characterized with regard to morphology, growth kinetics, anchorage-independent growth, tumorigenicity in athymic nude mice, and expression of kidney cell surface antigens. These results were compared with data from primary short term cultures of normal kidney epithelium. The overall success rate of establishing continuous renal cancer cell lines was 12.7%. In general, no significant difference in success was noted based on whether the specimen was derived from a primary or a metastatic lesion. However, all successfully established lines were derived from tumors exhibiting clinically "aggressive" behavior. All cell lines expressed proximal tubular cell differentiation antigens. Significant morphological heterogeneity was observed among normal kidney as well as kidney cancer cell lines in vitro. No significant difference in doubling time was found between cell lines of renal cancer and passage 1 cultures of normal kidney epithelium. Twenty-one of 30 (70%) lines assayed formed clones on soft agar and 26 of 33 (79%) lines grew in athymic mice. Among the 25 lines which were assayed for both soft agar growth and tumorigenicity in nude mice, this pair of phenotypic traits were concordant in 17 lines (60%). Four lines (16%) grew on agar but not in mice, while four other lines (16%) failed to grow in agar but were tumorigenic in mice.

[Biological markers in renal cell carcinoma]

The development of immunoassays for the diagnosis of renal cancer promises significant improvements in clinical treatment. Monoclonal antibodies have defined numerous kidney-associated antigens. In at least one instance (ADAbp), an immunoassay has already been established that is helpful in the diagnosis of benign renal diseases. A similar approach may also be useful in renal cancer. Similarly, in at least one instance a previously undefined peptide (HHM factor) has been cloned and sequenced. Synthesis of this peptide and the production of antibodies to it is imminent. The possibility of measuring this peptide and/or the many other aberrantly produced peptides associated with this cancer would presumably mean a substantial improvement in early diagnosis and therefore cure rates in renal cancer. The final role of chromosome changes in the diagnosis and determination of prognosis cannot yet be defined.

The conservative treatment of osteonecrosis of the femoral head. A comparison of core decompression and pulsing electromagnetic fields

Once roentgenographic changes are apparent, osteonecrosis of the femoral head in the adult generally progresses to osteoarthritis within two to three years. A variety of conservative surgical procedures have been devised to conserve the femoral head with varying success. This study examines the effectiveness of pulsing electromagnetic fields and core decompression in the treatment of osteonecrosis of the femoral head. Both techniques reduce the incidence of clinical and roentgenographic progression. Exposure to pulsing electromagnetic fields appears to be more effective in hips with Ficat II lesions than in hips with more advanced lesions.

[Complications and late sequelae following radical cystectomy and supravesicle urinary diversion]

Until recently radical cystectomy combined with urinary diversion was only justified by most urologists as a therapeutic measure for the management of bladder cancer, when other forms of treatment failed controlling the disease. This attitude was mainly based on a high morbidity and mortality rate of up to 20% of the cases. Improved selection of the patients, progress in improving preoperatively the physical conditions of the patients, intra- and post-operative intensive care and improvement of the surgical technique have contributed considerably to reduce the risks of this procedure. Effective preparation of the small and large bowel, early anticoagulation and digitalis medication as well as an efficient antibiotic treatment starting intraoperatively, and optimal parenteral hyperalimentation are of particular importance. Adjuvant preoperative radiation therapy and a simultaneously performed pelvic lymph node dissection do not contribute to an increased morbidity or mortality rate. Taking into account all available preventive measures, the mortality rate of about 20% 20 years ago has been reduced to about 1-5% at present.

Rapid radioimmunoassay for diagnosing acute tubular necrosis

A previously described method for recovering a proximal renal tubular epitheal antigen (HRTE-1) from normal human kidney was modified by using ion-exchange and immunoaffinity chromatography in order to create easily reproducible conditions for antigen isolation. Radioiodinated HRTE-1 was then used to establish a 3-hour, double-antibody radioimmunoassay (RIA) for the purpose of testing whether the urinary excretion of this antigen might seve as a useful marker of acute tubular necrosis (ATN). Urines from 51 patients (ATN, 22: chronic nephropathies, 24; prerenal azotemia, 5) and from 36 normal subjects were assayed for HRTE-1. 79% of ATN patients had abnormal antigen concentrations while 100% of all other urines had urine antigen concentrations within a previously established range for random normal urine samples. When used as a differential diagnostic test of either ATN versus chronic nephropathies, or of ATN versus prerenal azotemia, 90 and 81% discrimination was achieved, respectively. The majority of ATN and prerenal azotemia patients presenting with atypical conventional diagnostic parameters (urine Na, urine osmolality, urine sediment, fractional Na excretion) were correctly diagnosed by RIA. Further study of HRTE-1 excretion in acute and chronic renal diseases seems indicated, both to elucidate pathophysiologic mechanisms and to determine whether HRTE-1 is a clinically useful marker of ATN.