Monoclonal antibodies in urologic oncology

Expression of annexin II in conventional renal cell carcinoma is correlated with Fuhrman grade and clinical outcome

Conventional renal cell carcinomas (CRCCs) were investigated for the expression of annexin II (ANX II) to determine out whether this calcium-binding protein could serve as a useful prognostic marker. CRCCs and adjacent nonneoplastic tissue from 33 patients were investigated for ANX II by immunohistochemistry, RT-PCR, and western blot analysis. ANX II expression was correlated with tumor differentiation (Fuhrman grade) and to clinical outcome. Tumors were composed of ANX II positive and negative cells. In grade I tumors only a weak membranous staining was seen in immunopositive cells. In grade II and III tumors, however, ANX II was seen in the cytoplasm and at the cell membranes of tumor cells. On serial sections membranous and cytoplasmic immunoreactivity for ANX II occurred predominantly in eosinophilic cells whereas clear cells were mostly immunonegative. The ANX II expression in CRCCs was correlated with clinical outcome and Fuhrman grade. Since ANX II expression is correlated with Fuhrman grade and clinical outcome it may be a useful marker for prognosis in CRCC.

Expression of cell adhesion molecules in an established and characterized new human renal cell cancer line, CCF-RC7

In order to investigate the importance of cell adhesion molecules (CAMs) in renal cell carcinoma (RCC), a cell line, designated as CCF-RC7, was established from a human RCC of the clear cell type. CCF-RC7 was passaged over 50 times in vitro for 3 1/2 years. The cell line has an epithelial morphology and a doubling time of 30 h, forming colonies in soft agar with an average efficiency of 10.4% and producing clear cell tumors in athymic nude mice. CCF-RC7 cells have an aneuploid-hypotetraploid karyotype with a modal chromosome number of 82 and rearrangements in chromosomes 9, 12 and 14. Immunohistochemical and flow immunocytometric analyses revealed high expression of ICAM-1 (CD54), and Hermes antigen (CD44), which was significantly upregulated by cytokine and PMA treatment. VLA-4 was expressed on approximately 20% of tumor cells and could not be altered by cytokine or PMA stimulation. High expression of sialyl Lewis X was also demonstrated by immunohistological examination. This newly characterized cell line will serve as a useful model for the study of CAMs during hematogenous metastasis and host defense mechanisms in human RCC.

Renal cell carcinoma

Complete surgical resection of renal cell cancer confined to the kidney offers a hopeful prognosis of long-term remission or cure. Metastatic renal cell cancer is not effectively managed through the traditional modalities of surgery, chemotherapy, hormonal therapy, or radiation therapy. Quantum leaps in the understanding of immunobiology and molecular genetics, as well as the elucidation and application of biologic response modifiers, have created a climate of renewed enthusiasm for defining more active regimens for the management of metastatic renal cell cancer. As long-term remission and cure are highly unlikely for the majority of individuals presenting with advanced disease, attention to quality of life issues such as symptom control, cost containment, and honesty is appropriate. In diseases such as metastatic renal cell cancer where no effective standard of therapy has been demonstrated, participation in well-designed, carefully executed clinical trials with adequate reimbursement is encouraged for all eligible candidates. Individuals challenged with living with metastatic kidney cancer are aware of the gradual or precipitous nature of their declining process and generally do not harbor unrealistic hope for longterm survival. However, pain relief and comfort are reasonable hopes, and striving for and attaining an optimal quality of life will sustain both the individual and caregiver.

Interleukin-6 and TNF alpha production in human renal cell carcinoma

Several clinical and biological features suggest that cytokines implicated in the inflammatory response are produced by renal cell carcinoma (RCC). To define if alterations of tumor necrosis factor alpha (TNF alpha), interleukin 1 alpha (IL-1 alpha), IL-1 beta and IL-6 gene expression are present in this malignancy, samples from 19 tumors as well as samples from seven paired normal renal tissue were examined using Northern blot and immunohistochemical analysis. In addition, the expression of these cytokines was evaluated in seven RCC-derived cell cultures using Northern blot or RT-PCR. TNF alpha and IL-6 proteins were measured in culture supernatants using specific bio- and immunoassays. Consistent levels of IL-6 mRNA were detected in 17 of the 19 tested tumors whereas TNF alpha specific transcripts were present in seven of eight available RNA samples. TNF alpha and IL-6 mRNA were also detected in five of the seven paired normal kidneys. By immunolabeling, IL-6 antigen was not detected in RCC cells in any of the 19 studied samples. In contrast, using anti-TNF alpha antibody a strong labeling of stromal endothelia and macrophage cells was detected in all the 19 cases, and evident TNF alpha staining of the carcinoma cells themselves was observed in eight cases. Spontaneous IL-6 mRNA expression was detected in five RCC cell cultures and TNF alpha mRNA in four. The cultured cells exhibited positive TNF alpha immunolabeling in six of seven cases but were always IL-6 negative. Bioactive IL-6 was detected in all culture supernatants while bioactive TNF alpha was not detected.(ABSTRACT TRUNCATED AT 250 WORDS)

Monoclonal antibodies for intravesical radioimmunotherapy of human bladder cancer

Local administration of radioimmunoconjugates may allow successful tumor therapy. Bladder cancer appears well suited to this approach, because of its superficial and multifocal nature, and because it will allow direct intravesical administration of conjugates. Implantation of human bladder cancer cell lines in the bladder wall of nude rats results in tumor formation, providing an excellent model to test this. We have developed two murine monoclonal antibodies (MAbs), BLCA-8, IgG3, and BLCA-38, IgG1, both of which react with malignant cells and shed into voided urine of patients with transitional cell carcinoma (TCC) of the bladder, but not with normal bladder urothelial cells. Radioimmunoconjugates produced with 131Iodine (131I) or 125I have been used for biodistribution studies following administration directly into the bladder. Radioiodinated intact MAbs or Fabs administered intravesically into nontumor-bearing rats did not leak into the systemic circulation and were stable in urine for up to 100 h. Biodistribution studies carried out following intraperitoneal or intravesical administration of radioimmunoconjugates to tumor-bearing nude rats indicate good tumor uptake of both MAbs. Together with immunoreactivity assays, these studies demonstrate that 131I-labeled MAbs have considerable potential for intravesical radioimmunotherapy of human bladder tumors, and further studies are under way.

Genitourinary tract nuclear oncology

Currently available routine radionuclide procedures and on-going investigational scintigraphic studies of genitourinary tract tumors were reviewed. Emphasis was focused on the most commonly encountered tumors located in the kidneys, bladder, and prostate. Other imaging modalities, such as computed tomography (CT), magnetic resonance imaging (MRI), and sonography have replaced many of the routine radionuclide imaging procedures providing high-resolution images and anatomic details. The advantages of radionuclide procedures with their simple, uninvasive, and functioning nature will continue play important role in our management of tumors of the genitourinary tract.

Lewis blood group antigen expression by cultured normal ureteral epithelial cells

The importance of Lewis blood group antigens in recurrent urinary tract infections has led to a more detailed study of the expression of these antigens in an in vitro culture system. Expression of A, B, H, and Lewis blood group antigens by primary cultures of ureter epithelial cells was analyzed by flow cytometry. Cells maintained blood group determinants for up to 7 weeks in culture over three passages. In several specimens, the cells that exhibited expression of Lewis A (Le(a) and Lewis B (Le(b)) antigens increased dramatically over 2-3 passages in culture. Lewis Y (Le(y)) antigen expression was positive on all primary cultures tested. The effect of fetal bovine serum (FBS) on blood group antigen expression was evaluated. Increased concentrations of FBS in the growth media increased the expression of Le(a) and Le(b) antigens in certain specimens, but did not affect expression of the other blood group antigens. The effect of FBS on blood group antigen expression of cultured cells depended on the Lewis blood type of the individual donating the specimen. To evaluate the heterogeneity often seen in Le(a) and Le(b) antigen expression, dual staining of cells for Le(a) and Le(b) antigens was performed. The results of these studies show for the first time that Lewis blood group antigens are expressed by cultured normal ureteral epithelial cells and that the pattern of expression of Le(a) and Le(b) changes over time. Furthermore, an individual cell may simultaneously express more than one Lewis antigen on its surface.

Renal cell carcinoma

Renal cell carcinoma accounts for 3% of all adult cancers and has many unusual features in its presentation, diagnosis, and management. It develops in a significant number of patients with acquired renal cystic disease, a disorder found almost exclusively in chronic hemodialysis patients. Abnormalities of chromosome 3 are frequently found in sporadic and familial forms. Radical nephrectomy remains the only potentially curative therapy for this tumor.

Growth and metastasis of human bladder cancer xenografts in the bladder of nude rats. A model for intravesical radioimmunotherapy

A potentially useful therapeutic approach to the treatment of human bladder cancer is intravesical therapy with radiolabelled monoclonal antibodies (MAbs). We have established an animal model to study this approach. Inoculation of cloned 2B8 cells derived from the human bladder cancer cell line, UCRU-BL-17, into the bladder wall of nude rats pre-irradiated with 900 rads, resulted in local tumour growth in 39/40 (97.5%) animals, with invasion or metastases to distant organs in 25% of cases. Both the bladder tumours and the metastases were morphologically similar to the original biopsy sample from which the cell line, UCRU-BL-17, was established. The cells were of human origin, as shown by expression of HLA antigens, Alu probing, and cytogenetic analysis. Preliminary studies indicated that i.p. injection of anti-human bladder cancer monoclonal antibody (MAb), BLCA-38, radiolabelled with either iodine 131 or samarium 153 (153Sm), resulted in tumour localisation, with tumour-to-blood ratios of 5.04 (131I), and 4.3 and 3.1 (153Sm) respectively. We now aim to examine the efficacy of the intravesical route for radioimmunotherapy in the nude rat model. This model will also serve for preclinical studies on the efficacy of systemically injected radioimmunoconjugates for control of metastatic growth.

Bellini duct carcinoma: further evidence for this rare variant of renal cell carcinoma

Bellini duct carcinomas have recently been identified as a new entity in the spectrum of renal cell carcinomas and 10 cases have now been reported. The present paper adds detailed clinical and morphological data on six new cases. In addition, immunohistological and electronmicroscopical results support the origin of these tumours from the renal collecting ducts, especially the papillary ducts (Bellini ducts). A set of immunohistological reactions, including reactions to cytokeratins 13 and 19, vimentin and UEA-1 was found to facilitate the differential diagnosis of Bellini duct carcinomas from other renal cell carcinomas and infiltrating urothelial carcinomas of renal pelvis.

Detection of malignant cells in voided urine from patients with bladder cancer, a novel monoclonal assay

A simple assay is described for detecting malignant cells in the voided urine from patients with transitional cell carcinoma of the bladder. Agarose-embedded urothelial cells from 24 biopsy-proven cancer patients and 10 controls were stained for surface immunofluorescence with four monoclonal antibodies reactive with human bladder cancer and three monoclonals reactive with blood group A. Reactivity was assessed by fluorescence microscopy. One antibody, BLCA-8 appeared to have particular diagnostic utility. Thus, 24.3 +/- 5.8 percent of outer layer and 27.0 +/- 4.6 percent of inner layer urothelial cells reacted with BLCA-8 in patient samples, compared to 2.9 +/- 1.0 and 0.8 +/- 0.5 percent of similar cells from control urines. BLCA-8 antigen expression was found to be relatively stable even after prolonged exposure to urine. In a comparison with conventional cytology, samples from 4/8 patients were considered positive by standard methods, whereas, 8/8 were BLCA-8 positive. This new technique may thus be a useful adjunct to conventional methods.

Diagnostic and therapeutic utility of monoclonal antibodies in urologic oncology

Remarkable advances in the treatment of urologic malignancies have recently been made. Monoclonal antibodies selective for a variety of normal and malignant urologic tissues have been useful in defining normal antigens and tumor-associated antigens and have potential as diagnostic and immunotherapeutic agents. In renal cancer, monoclonal antibodies can define serum markers, radiolabel tumor xenografts, and assist in specific tissue diagnosis. Additionally, there is potential for these antibodies either alone or as conjugates to localize and kill tumors. Monoclonal antibodies to bladder cancer associated antigens are able to demonstrate differential antigen expression on superficial versus invasive tumors, to refine urinary cytologic diagnosis of bladder cancer, and to predict invasive recurrence of superficial cancer. Monoclonal antibodies have localized bladder tumor xenografts and can inhibit tumor growth when conjugated to radioisotopes or toxins. In prostate cancer monoclonal antibodies to prostate antigens are not usually tumor specific. Monoclonal antibodies to prostate antigen (PA) and prostatic acid phosphatase (PAP) are able to localize prostate cancer metastases. Chemotherapy-conjugated anti-PAP monoclonal antibodies have demonstrable inhibition on human prostate cancer xenografted tumor growth. Monoclonal antibodies have defined normal and tumor-associated antigens in urologic cancers and are expected to be useful in immunodiagnosis and cancer therapy in the near future.

Biologic response modifiers and urologic malignancies

Biologic response modifiers represent a new generation of immunotherapeutic agents. Although biologic response modifiers such as interferon have been moderately successful in treating B-cell malignancies, they have not been as successful for the management of advanced genitourinary malignancies. The measurement of biologic response modifiers in the urine may prove useful for directing intravesical BCG therapy for the treatment of superficial bladder cancer or for directing the use of prophylactic antibiotics for the management of urinary tract infections.