Intracellular Na+:K+ ratios in human cancer cells as revealed by energy dispersive x-ray microanalysis.

Intranuclear sodium, potassium, and chloride contents were measured by energy-dispersive x-ray microanalysis in freeze-fractured, freeze-dried, bulk-tumor samples taken from 10 patients suffering from invasive urogenital cancers. Human biopsies were carried out during the first diagnostic interventions before any cytostatic treatment had been applied. Pathohistological diagnosis established the malignancy in each case. The cancers were classified in three types: keratinizing, transitional cell, and hypernephroid carcinoma. More than 250 cell nuclei were measured from each type of cancer. The results were compared with those obtained in intact human urothelium taken from patients having no malignant processes. Proximal and distal tubular epithelial cell nuclei representing the origin of human hypernephroid cancer were also measured in rat kidney because corresponding healthy human material cannot be obtained. The analyses revealed, in all three types of cancer cells, that the average intranuclear sodium content increased more than three-fold, the potassium content decreased 32, 16, and 13%, respectively; meanwhile the chloride content increased, but to a lesser extent than did the sodium. The intranuclear Na+:K+ ratios were more than five-fold higher in the cancer cells on the average, and their distribution histograms were much broader than in the normal human urothelium and in the tubular cell nuclei of the rat kidney. The results obtained fit well with the theory of Cone, C. D., Jr. 1971. J. Theor. Biol. 30: 151-181 according to which the sustained depolarization of the cell membrane may be of mitogenic effect.

Parathyroid hormonelike protein from human renal carcinoma cells. Structural and functional homology with parathyroid hormone.

A variety of solid tumors secrete proteins that are immunochemically distinct from parathyroid hormone (PTH) but activate PTH-responsive adenylate cyclase. Such PTH-like proteins have been proposed as mediators of the hypercalcemia and hypophosphatemia frequently associated with malignancies. We purified to apparent homogeneity a PTH-like protein with a molecular weight of 6,000, that is produced by human renal carcinoma cells. The amino-terminal sequence of the PTH-like protein and that of human PTH were found to display at least five identities in the first 13 positions. The purified protein bound to PTH receptors, activated adenylate cyclase in renal plasma membranes, and stimulated cAMP formation in rat osteosarcoma cells. The PTH-like protein reproduced two additional effects of PTH, stimulation of bone resorption in fetal rat limb bone cultures and inhibition of phosphate uptake in cultured opossum kidney cells. These properties are consistent with a role for PTH-like proteins as mediators of the syndrome of malignancy-associated hypercalcemia.

Production of a low molecular weight eosinophil polymorphonuclear leukocyte chemotactic factor by anaplastic squamous cell carcinomas of human lung.

A peptide of approximately 300-400 daltons exhibiting in vitro chemotactic activity for human polymorphonuclear (PMN) leukocytes, with a preference for the eosinophil series, was isolated from extracts of anaplastic lung carcinomas of the large squamous cell type obtained from three patients with marked peripheral blood hypereosinophilia and eosinophilic infiltration of the tumors and surrounding normal pulmonary tissues. This chemotactic factor was termed ECF-LSC (eosinophil chemotactic factor of lung squamous cell carcinoma). ECF-LSC appeared in the urine of two of the patients in increasing quantities late in the course of their disease and was also elaborated by long-term cultures of dispersed tumor cells from the same two patients. Three anaplastic large cell bronchogenic carcinomas which were not associated with tumor tissue or peripheral blood eosinophilia, a bronchogenic adenocarcinoma from a patient with only peripheral eosinophilia, and a renal cell carcinoma metastatic to the lungs and associated with transient pleural tissue and fluid eosinophilia were all devoid of ECF-LSC. ECF-LSC from tumor tissue extracts, urine, and tumor cell culture medium was comparable to the mast cell-associated tetrapeptides of the eosinophil chemotactic factor of anaphylaxis (ECF-A) in size, but eluted from Dowex-1 at pH 5.0-3.5 in contrast to the more acidic ECF-A tetrapeptides which eluted at pH 3.2-2.2 ECF-LSC, like the tetrapeptides of ECF-A, had a secondary chemotactic activity for neutrophil PMN leukocytes, but not mononuclear leukocytes, and deactivated both eosinophil and neutrophil PMN leukocytes so that they would not respond to a subsequent in vitro chemotactic stimulus. Eosinophils from the two patients with urinary excretion of ECF-LSC and the highest concentrations in tumor extracts were hyporesponsive in vitro to homologous and heterologous chemotactic stimuli, suggesting that ECF-LSC had deactivated the eosinophils in vivo.

MDR1 RNA levels in human renal cell carcinomas: correlation with grade and prediction of reversal of doxorubicin resistance by quinidine in tumor explants.

We examined the distribution of RNA levels expressed by the multidrug-resistance gene (MDR1, also known as PGY1) in 42 renal cell carcinoma (RCC) samples (38 primary and four metastatic lesions). The median MDR1 RNA level for the 38 primary lesions, expressed relative to the level for KB-3-1 cells, was approximately one-half of the level in multidrug-resistant KB-8-5 cells. Elevated MDR1 RNA levels were also observed in three of the four metastatic lesions. The mean MDR1 RNA level was higher in well-differentiated RCCs than in those that were poorly differentiated, suggesting that the increased expression of the MDR1 gene in RCCs originates from the increased expression in renal proximal tubule cells. To clarify the association of the MDR1 protein product P-glycoprotein with natural resistance to doxorubicin (ADR) in RCCs, we evaluated the effects of quinidine on in vitro sensitivity to ADR in 16 RCC samples, using a [3H]thymidine incorporation assay. The enhancing effect of quinidine (7.5 micrograms/mL) on sensitivity to ADR was statistically significant only in the group with high MDR1 RNA levels. Similar enhancement by quinidine of sensitivity to ADR was also observed in the established RCC cell lines in which MDR1 RNA levels were high. These results suggest that P-glycoprotein is active in the natural resistance of RCCs to ADR.

Expression of lacto series type 2 antigens in human renal cell carcinoma and its clinical significance.

We performed immunohistochemical examination of serial sections of human fetal and adult renal tissue as well as human renal carcinoma tissue, using monoclonal antibodies T5A7, 1B2, FH2, FH4, and FH6. These monoclonal antibodies were directed to lacto series type 2 antigens with sugar-chain structures: lactosylceramide, lactoneotetraosylceramide (paragloboside), Lex (a chemically well-defined fucosyl carbohydrate antigen), difucosyl Lex, and sialosyl-difucosyl Lex, respectively. The staining pattern in fetal renal tissue changed significantly according to the stage of organogenesis. In addition, expression of the antigens, especially paragloboside and sialosyl-difucosyl Lex, was closely related to the prognosis of the patient. These results suggest that the expression of a series of oncofetal antigens in development or differentiation of organs is reflected in the reversion to an immature pattern of antigenic expression in tumor tissue. The pattern of antigen expression in renal tumors offers a good criterion for ascertaining the degree of tumor differentiation and malignancy and is valuable for determining prognosis.

1,25-Dihydroxyvitamin D3 receptor measurement in primary renal cell carcinomas and autologous normal kidney tissue.

Recently it was reported that 1-alpha,25-dihydroxyvitamin D3 [1,25-(OH)2D3] inhibited cell growth in a cell line derived from a metastasis from renal cell carcinoma. We have examined samples from 23 primary renal cell carcinomas for 1,25-(OH)2D3 receptor content, and compared it with the concentrations in autologous normal kidney tissue. Nineteen of 23 (83%) renal cell carcinomas had detectable (above 1 fmol/mg protein) 1,25-(OH)2D3 receptor levels, and 15 of 23 (65%) had levels above 5 fmol/mg protein. Mean value for the renal cell carcinomas was 8.2 fmol/mg protein (range, 0-28 fmol/mg protein), and the mean value for autologous normal kidney tissue was 23.1 fmol/mg protein (range, 6.6-53.7 fmol/mg protein). The 1,25-(OH)2D3 receptor levels in the renal cell carcinomas were significantly lower than in the autologous normal kidney tissue (P less than 0.001). The 1,25-(OH)2D3 receptor was characterized by sucrose gradient analysis and DNA-cellulose chromatography. The features found for renal cell carcinoma were similar to the 1,25-(OH)2D3 receptor in normal human tissue. No correlation of 1,25-(OH)2D3 receptor levels to clinical parameters was found. This study shows that carcinomas originating from the kidney, the major vitamin D regulating organ, usually contain the 1,25-(OH)2D3 receptor. The receptor may have a cellular function in the transformed cell.

Occurrence of the tumor-specific, calcium-binding protein, oncomodulin, in virally transformed normal rat kidney cells.

Oncomodulin, an apparently tumor-specific calcium-binding protein, has been detected in many chemically induced rat hepatomas. It is now possible to detect, by radioimmunoassay and immunofluorescence, the presence of oncomodulin in normal rat kidney cells virally transformed by avian sarcoma virus. By contrast, it was not detected in uninfected, nonneoplastic normal rat kidney cells. The protein was isolated and purified by a novel high-performance liquid chromatography procedure and shown to be identical to that isolated previously from rat hepatoma. The cellular levels of oncomodulin approached the levels of calmodulin in avian sarcoma virus-transformed normal rat kidney cells, suggesting that the total calcium-binding activity of the cell may play a role in expression of the transformed phenotype.

Activation of the parathyroid hormone receptor-adenylate cyclase system in osteosarcoma cells by a human renal carcinoma factor.

Human renal carcinoma cell line 786-0 elaborates a protein that is structurally and immunochemically distinct from parathyroid hormone (PTH) and that activates renal cortical adenylate cyclase via an interaction with the PTH receptor. Because of the high frequency of excessive bone resorption and resultant hypercalcemia in patients with malignant disease we evaluated the ability of this 786-0 cell factor to reproduce PTH action in bone-derived cells. The 786-0 factor as well as bovine PTH (BPTH) (1-34) and prostaglandin E1 produced marked increases in cyclic adenosine 3':5'-monophosphate (cAMP) accumulation in the clonal rat osteosarcoma cell line UMR-106. A competitive antagonist of PTH action, [norleucine8, norleucine18, tyrosine34] BPTH(3-34)amide, blocked the cAMP stimulation produced by 786-0 factor and BPTH(1-34) but not that produced by prostaglandin E1. In the presence of forskolin (0.1 microM) UMR-106 cells were extremely sensitive to 786-0 factor, showing significant increases in cAMP production at a concentration 10-fold less than that required to activate adenylate cyclase in renal membranes. In contrast UMR-106 cells were less sensitive to BPTH(1-34) than were renal membranes. This preferential increase in sensitivity to 786-0 factor was not seen in membranes prepared from UMR-106 cells suggesting the importance of cytosolic components. Six additional human genitourinary carcinoma cell lines were found to produce factors that increased cAMP levels in UMR-106 cells. We conclude that 786-0 factor is a potent activator of the PTH receptor-adenylate cyclase system in these bone-derived cells. These findings are consistent with the view that cancer-associated hypercalcemia may frequently be attributable to tumor secretion of proteins (such as 786-0 factor) that are distinct from PTH but are capable of activating skeletal PTH receptors.

Histochemical and immunohistochemical characterization of surgically resected and heterotransplanted Wilms' tumor.

Nine surgically resected Wilms' tumors (WIT) and nude mouse heterotransplants from one WIT were studied by histochemistry and immunohistochemistry. Histochemistry showed acid phosphatase in all cells, while alkaline phosphatase and gamma-glutamyl transpeptidase were present in only some tubules. Using immunohistochemistry, antibodies to the intermediate filaments cytokeratin and vimentin distinguished tubular epithelium and mesenchyme, respectively. WIT tubules were also identified using antibody against a structural component (epithelial membrane antigen) and a secretory product (uromucoid) associated with distal convoluted tubules of normal kidney. Basement membrane surrounding the tubules of WIT was demonstrated using antibody to type IV collagen plus laminin. Different blastema subpopulations were negative or stained positively with antibodies to cytokeratin and vimentin. Production of basement membrane by blastema was also shown. Fetal antigen expression in WIT was examined using the monoclonal PI 153/3 and J5 antibodies. The blastema and tubules of WIT were strongly stained by PI 153/3, which did not label normal adult kidney, and weakly stained by J5, which strongly labeled glomeruli and proximal convoluted tubules of normal kidney. These studies show that WIT blastema is heterogeneous in intermediate filament subtypes, while WIT tubules more closely resemble distal than proximal convoluted tubules of adult kidneys but also retain expression of fetal antigens.

Expression of transforming growth factor alpha in normal human adult kidney and enhanced expression of transforming growth factors alpha and beta 1 in renal cell carcinoma.

Normal kidney and renal cell carcinoma tissues from ten patients were studied for mRNA and DNA for both transforming growth factors alpha and beta 1. Northern and Southern hybridizations were conducted on samples extracted from the solid tumor and surrounding normal tissues and two tumor-derived cell lines. Low levels of constitutive expression of TGF-alpha mRNA were detected in all normal kidney tissues; six of the ten patients, however, demonstrated an increased (2- to 8-fold) expression of TGF-alpha in the tumor versus normal kidney as determined by densitometry of RNA blots. All ten patients had elevated mRNA levels for TGF-beta 1 in the tumor (2.5-to 22-fold increase) relative to normal kidney. Two tumor-derived cell lines also expressed TGF-alpha and TGF-beta 1 mRNA. Southern blot hybridization of the DNA extracted from the normal tumor pairs revealed no gene amplification or gross rearrangement for either the TGF-alpha or TGF-beta 1 genes. These results demonstrate the expected constitutive expression of TGF-beta 1 by normal kidney; however, the constitutive expression of TGF-alpha by Northern blot analysis in normal adult human kidney is previously unreported. Enhanced expression of TGF-alpha and TGF-beta 1 mRNA in solid tumor may be related to the development of renal cell carcinoma.

Modulation of pro-epidermal growth factor, pro-transforming growth factor alpha and epidermal growth factor receptor gene expression in human renal carcinomas.

We have analyzed the expression of the genes for the precursors of epidermal growth factor (pro-EGF) and transforming growth factor alpha (proTGF-alpha) as well as for the EGF receptor in tissue specimens of a large number of adult patients with renal cell carcinoma. Since normal kidney tissue was available from the same patients we could directly compare the expression of these genes in tumors with that in adjacent normal renal tissue. Our experiments reveal underexpression of the proEGF gene in all tumors analyzed (21 of 21) and overexpression of the genes for proTGF-alpha (33 of 33 analyzed) and EGF receptor (22 of 23 analyzed) in tumor samples, when compared with normal kidney tissue. The expression of the proTGF-alpha gene appeared to depend on grade and differentiation of the tumor, since well differentiated tumors (grade 1) expressed more proTGF-alpha mRNA than the adjacent normal tissue but significantly less than poorly differentiated tumors (grade 2 or 3), which are the most aggressive ones. In none of these tissue specimens did we find, by Southern analysis, amplification of the proTGF-alpha or EGF receptor gene. Therefore, overexpression of these genes must be due to another effect, perhaps an alteration of their mRNA turnover. Although the EGF receptor gene (c-erbB1) is overexpressed in nearly all carcinomas analyzed, there was no linear coexpression with the proTGF-alpha gene. In contrast, transcription of the proEGF gene was completely turned off in tumor tissue. Although we have found by restriction fragment length polymorphism analysis, in one of three tumor samples, evidence for a somatic mutation within the proEGF gene, we do not know yet, due to the limited number of Southern analyses, whether this somatic mutation is causally involved in the decrease of proEGF mRNA expression and, hence, is representative of renal cell carcinoma. To our knowledge, this is the first observation on primary tumor tissue in humans that upon malignant transformation the gene for a polypeptide growth factor gene is underexpressed.

Structural differences in ferritins from normal and malignant rat tissues.

Ferritins purified from several normal and malignant rat tissues were examined for amino acid composition, content of tryptic peptides, available sulfhydryl groups and subunit sizes and proportion. Ferritin extracted from adult kidney, neonatal liver and hepatic and renal tumors differed from the ferritin of adult rat liver in migration on electrophoretic gels and in antibody affinity, but did not differ among themselves. Nevertheless, they showed distinctive differences in amino acid composition and tryptic peptide content. All of them and also adult liver ferritin contained two major species of subunits differing in molecular weight. The proportions of subunits, and the available sulfhydryl groups of the intact ferritin molecules, differed among these tissue ferritins. On the basis of amino acid and peptide content, the ferritins of hepatomas and the renal tumor analyzed showec the greatest similarity but not identity. The ferritin of neonatal liver was next most similar. Kidney ferritin differed considerably in composition from tumor and neonatal ferritins, while adult liver ferritin was the most extremely divergent of the series examined. A similar progressive difference was found on examining the proportions of subunits and sulfhydryl groups in these ferritins. However, changes in subunit proportion cannot explain the amino acid and peptide compositional changes.

Two distinct tumor-derived, parathyroid hormone-like peptides result from alternative ribonucleic acid splicing.

A novel PTH-like peptide has recently been isolated and cloned from human tumors associated with the syndrome of humoral hypercalcemia of malignancy. The deduced product of the initial clones to be reported is a 177 amino-acid protein, consisting of a 36 amino-acid precursor sequence followed by a 141 amino-acid mature peptide. Southern analysis of genomic DNA is compatible with a single-copy gene, but Northern analysis of mRNAs from both tumors and normal tissues consistently reveals multiple hybridizing transcripts, suggesting the possibility of alternative RNA splicing. We provide here direct evidence of alternative RNA splicing by the identification of a second cDNA clone in a human renal carcinoma cDNA library. As compared to the initial clone, this cDNA contains a foreshortened 5'-untranslated region but is otherwise identical until the distal portion of the coding region, at which point it diverges completely to encode a 166 amino-acid mature peptide with 27 amino acids of unique C-terminal sequence. The relative lengths of the primary translation products encoded by these two cDNAs were confirmed by transcription and translation in vitro, and both products were shown to be processed by added microsomes. The unique 3'-ends of these two cDNAs, as well as that of a third cDNA isolated by another laboratory, were used to identify one or more hybridizing transcripts corresponding to each cDNA in mRNA from a human renal carcinoma as well as in mRNA from normal human keratinocytes. We conclude that alternative RNA splicing results in mRNAs which encode multiple PTH-like peptides.(ABSTRACT TRUNCATED AT 250 WORDS)

Familial extra-adrenal pheochromocytoma. A new syndrome.

Pheochromocytomas in the same anatomic site, the right renal hilum, occurred in a family over three successive generations. For two patients in the latter two generations, scintigraphy with iodine 131-tagged metaiodobenzylguanidine (MIBG) showed tumors only in the region of the right renal hilum, thus indicating that they were primary lesions. At surgery, except for lymph node metastases noted microscopically in one patient, tumors were found only near the right renal hilum. The adrenal glands seemed normal on inspection, palpation, and computed tomography. In another family, a mother and son had primary pheochromocytomas arising from the urinary bladder. We suggest that primary extra-adrenal pheochromocytoma is a syndrome in which specific genetic abnormalities determine sites of tumor development.

The relationship of polysialic acid and the neural cell adhesion molecule N-CAM in Wilms tumor and their subcellular distributions.

In previous studies we have reported that polysialic acid is an oncodevelopmental antigen in human kidney but its relationship to the neural cell adhesion molecule (N-CAM) remained undefined. In the present study, we showed by the combination of immunoprecipitation and immunoblotting that renal polysialic acid is a structural component of N-CAM polypeptide and that two highly sialylated N-CAM isoforms of approximately 120 kDa and 140 kDa existed in Wilms tumor. The presence of a cell surface coat composed of polysialic acid and N-CAM was revealed by immunoelectron microscopy, and morphological evidence for its involvement in modulating cell-cell adhesion has been provided. Furthermore, highly sialylated N-CAM was detectable extracellularly. N-CAM immunolabeling was present in compartments from the nuclear envelope to the plasma membrane. However, polysialic acid was only detectable at the cell surface suggesting that in Wilms tumor cells sialyl polymer synthesis may occur partially or exclusively at this site.

Immunohistochemistry of capillary hemangioblastoma. Immunoperoxidase-labeled antibody staining resolves the differential diagnosis with metastatic renal cell carcinoma, but does not explain the histogenesis of the capillary hemangioblastoma.

We used a battery of antigens to determine whether immunohistochemistry can (a) contribute to resolving the histogenesis of the stromal component of the capillary hemangioblastoma, and (b) answer cases of difficult pathologic differential diagnosis with metastatic clear cell carcinoma. The stromal cells of the capillary hemangioblastoma are antigenically polymorphous and may express immunoreactive erythropoietin, renin, keratin, Leu M1, Leu 7, actin, neuron-specific enolase, S100 protein, and glial fibrillary acidic protein. However, the use of epithelial membrane antigen allows certain histopathologic distinction between capillary hemangioblastoma and metastatic clear cell carcinoma.

Renin messenger RNA localization in congenital mesoblastic nephroma using in situ hybridization.

Renin messenger (m) RNA distribution was studied in congenital mesoblastic nephroma, a usually benign renal tumour of early infancy which may be associated with excess renin production and hypertension. Using in situ hybridization with synthetic radiolabelled oligonucleotide probes combined with immunohistochemical studies, renin expression was found in areas of tumours containing recognizable cortical structures including glomeruli and tubules. Renin mRNA was also detected in vessels and larger vascular spaces within the tumour not associated with cortical structures. Cells in the tumour vessel walls and sinusoids which expressed renin also stained positively for vascular smooth muscle-specific alpha actin.

Combined beta-galactosidase and immunogold/silver staining for immunohistochemistry and DNA in situ hybridization.

A combination of beta-galactosidase enzyme and the immunogold/silver staining method was studied for evaluation of double-staining experiments. Applications are shown for immunohistochemical double staining using two monoclonal antibodies and for combined immunohistochemistry and DNA in situ hybridization in one tissue section. The following advantages for the present double-staining method were evaluated: superior sensitivity of the immunogold/silver staining method for at least one epitope, which also allows detection of biotinylated DNA probes. The structure of the indolyl precipitate after revelation of beta-galactosidase activity did not show a concealing effect during a sequential double-staining method, as compared with the visualization of peroxidase with diaminobenzidine. These factors, and the sharply contrasting colored reaction products of beta-galactosidase (blue-green) and the immunogold/silver staining method including silver enhancement (brown-black), allow clear distinction of mixed-stained cell constituents.

Activities of serine hydroxymethyltransferase in murine tissues and tumours.

The specific activity of the enzyme serine hydroxymethyltransferase (EC 2.1.2.1) was determined in various murine, rat and human tumour cell lines. The activities of the enzyme were also investigated in tissues of non-tumour bearing DBA/2 mice and BALB/c mice bearing the PC6 ascites tumour. The highest enzyme activity in the murine tissues was found in the liver and then the kidneys. The enzyme was present in all the tissues assayed. The activities of enzyme found in the tumours varied considerably, with the PC6 ascites, Walker 256 and Lewis lung cells, being the highest.

Glucocorticoid receptors in human tumors.

Glucocorticoid receptors were examined in a range of solid human tumors. In addition to breast carcinomas, subsets of other tumor types (notably renal cell carcinomas) contain concentrations of these receptors characteristic of glucocorticoid-responsive tissues. The physico-chemical properties of the single glucocorticoid receptor present in the human tumors resembled those of the glucocorticoid receptor in rat tumors and the predominant form found in normal target tissues of the rat.