Biomedical subjects

C L Corless

Publications and source records attributed to C L Corless.

At least 37 records · Page 2Linked to original sources

PubMed1999

Acute and chronic renal effects of recombinant human TGF-beta2 in the rat.

The expression of transforming growth factor-beta (TGF-beta) correlates with the incidence of renal glomerular and interstitial injury, however, nothing is known of the effect of these proteins on renal hemodynamics. This study examines the renal hemodynamic and morphologic effects of recombinant human TGF-beta2 in normal male Sprague Dawley rats. Acute infusion of TGF-beta (1.2 microg/kg per min) induced no hemodynamic changes, except for a modest though significant fall in mean arterial pressure. Administering TGF-beta2 at varying doses (20, 100, and 400 microg/kg) for 9 wk caused modest increases in systolic BP and proteinuria and minimal tubular interstitial fibrosis, however, renal hemodynamic end points were not significantly altered. TGF-beta2 (800 microg/kg) was also administered to volume-depleted rats for 7 consecutive days. In contrast to the findings in volume-replete animals, administration of TGF-beta2 to volume-depleted rats caused a marked reduction in GFR and medullary blood flow. Histologic fibrosis of the medullary vasa recta and cortical interstitium was seen, but glomeruli were unaffected. Thus, acute and short-term chronic TGF-beta2 administration did not induce major renal changes in the volume-replete state, however, TGF-beta2 combined with volume depletion caused medullary hypoperfusion and reduced GFR.

Analysis of Variance↗

PubMed1998

Association of cytomegalovirus genotype with graft rejection after liver transplantation.

BACKGROUND: The envelope glycoprotein gB of human cytomegalovirus (CMV) occurs as one of four main genotypes. Some previous studies have proposed a relationship of CMV gB genotype to the frequency of symptomatic infection and to clinical outcomes in both transplant and human immunodeficiency virus-infected populations. Our aim was to define the distribution of CMV gB genotypes and the impact on acute cellular rejection and graft/patient survival after orthotopic liver transplantation (OLT). METHODS: Between October 1988 and December 1996, 325 patients underwent cyclosporine-based OLT at our center. CMV infection was surveyed prospectively and defined as viral isolation from blood or urine; 53 (16%) patients had detectable CMV. Isolates were genotyped by polymerase chain reaction amplification and restriction digest analysis. RESULTS: The distribution of CMV genotypes was: gB1, 19 (36%) patients; gB2, 15 (28%) patients; gB3, 13 (24%) patients; and gB4, 4 (8%) patients. Two patients (4%) had mixed infection (1 + 3, 1 + 4). Age, preOLT diagnosis, use of ganciclovir prophylaxis, basal immunosuppression, mean number of HLA donor/recipient mismatches, and United Network of Organ Sharing status were comparable among patients with different genotypes. Patients with gBl had a significantly higher mean number of acute rejection episodes (1.52+0.30 vs. 0.67+0.22; P=0.027). However, there was no difference in rejection severity, including OKT3 usage or FK506 conversion, or development of chronic rejection among patients with different genotypes. The gB genotype did not affect the development of symptomatic or tissue-invasive CMV disease, detected in 15 patients. Actuarial rates of patient (odds ratio [OR] 3.0; confidence interval [CI] 1.49-6.0) and graft (OR 2.57; CI 1.25-5.22) survival were significantly diminished in the group with CMV infection versus those without CMV (P<0.0001 for both), but there was no association with CMV genotype. CONCLUSIONS: (1) Patients with CMV infection had significantly reduced patient and graft survival rates at 1 and 5 years after OLT as compared with OLT recipients without CMV infection. (2) CMV genotype gB1 was associated with a higher mean number of acute rejection episodes.

Adult↗

PubMed1998

Timing and severity of initial hepatitis C recurrence as predictors of long-term liver allograft injury.

BACKGROUND: The majority of patients infected with hepatitis C virus (HCV) undergoing liver transplantation develop evidence of histologic recurrence, and multiple mechanisms are likely poised to affect long-term allograft injury. The purpose of this analysis was to study the hypothesis that histologic and biochemical features at the onset of HCV recurrence predict the long-term evolution of allograft hepatitis. METHODS: We studied 34 consecutive liver transplant recipients with evidence of histologic HCV recurrence and with a minimal histologic follow-up of 1 year (up to 6.2 years; mean: 696+/-83.2 days). Two-hundred and seventy-eight serial allograft biopsies (mean: 6.85+/-0.62 per patient, range: 4-21) were analyzed. The hepatic activity index was utilized to quantitate piecemeal necrosis, intralobular degeneration, portal inflammation, and hepatic fibrosis. The presence of hepatocyte ballooning degeneration and cholestasis was also assessed. RESULTS: Although there was no significant difference with regard to initial hepatic activity index scores between patients who ultimately developed allograft cirrhosis (group 1; n=8) versus those with milder hepatitis (group 2; n=26), the finding of ballooning degeneration/cholestasis was more frequent in the former group (P=0.04). The distribution of HCV genotypes, the mean follow-up after orthotopic liver transplantation, the mean number of allograft biopsy specimens per patient, basal immunosuppression, and incidence of rejection were comparable in both groups. Patients who ultimately developed allograft cirrhosis had significantly higher initial total bilirubin at the onset of histologic recurrence and peak total bilirubin (pT. Bili, the highest value in the ensuing month). Actuarial rates of moderate-to-severe allograft hepatitis were significantly greater in patients with pT. Bili > or = 3.5 mg/dl (P=0.004). Multiple regression analysis identified pT. Bili as the only independent predictor of allograft cirrhosis. CONCLUSIONS: Features at the onset of histologic HCV recurrence predict the natural history of allograft injury; specifically, marked, transient hyperbilirubinemia is associated with the subsequent development of allograft cirrhosis.

Biopsy↗

PubMed1998

Biliary tract complications of side-to-side without T tube versus end-to-end with or without T tube choledochocholedochostomy in liver transplant recipients.

BACKGROUND: Biliary anastomotic complications remain a major cause of morbidity in liver transplant recipients, ranging between 10% and 50% in large clinical series. An end-to-end choledochocholedochostomy with or without T tube (CDCD EE with T tube and CDCD EE w/o T tube) and a Roux-en Y choledochojejunostomy have been standard methods for biliary drainage. METHODS: The objectives of this retrospective study were to: (1) evaluate the incidence of biliary tract complications using a new method of side-to-side choledochocholedochostomy without T tube (CDCD SS w/o T tube) and (2) compare the results of CDCD SS w/o T tube with those of CDCD EE with T tube and CDCD EE w/o T tube. From September 1991 through June 1996, 279 orthotopic liver transplants were performed in 268 patients and followed through December 1996 (minimum of 6 months' follow-up). A total of 227 CDCD anastomoses in 220 patients were studied (7 retransplants > 30 days): CDCD EE with T tube (n=124), CDCD EE w/o T tube (n=44), and CDCD SS w/o T tube (n=59). RESULTS: Sixty-nine biliary complications were observed in 220 patients (30%). Anastomotic and/or T-tube leaks were seen in 43 patients (19%), and anastomotic strictures were found in 26 patients (12%). Forty patients (18%) required percutaneous or endoscopic stent placement (6%) or surgical interventions (12%). CDCD EE with T tube had the highest incidence of biliary leak requiring rehospitalization but the lowest anastomotic stricture and intervention rate and the lowest 6-month mortality rate. CONCLUSIONS: CDCD EE with T tube was superior to CDCD EE or CDCD SS w/o T tube despite the increased number of rehospitalizations. CDCD SS w/o T tube did not offer significant advantages over conventional biliary anastomotic techniques.

Bile Ducts, Extrahepatic↗

PubMed1998

Hepatic allograft abscess with hepatic arterial thrombosis.

BACKGROUND: Intrahepatic abscess (IA) is an uncommon complication after liver transplantation (OLTx) usually found in the setting of hepatic arterial thrombosis (HAT) often with associated biliary tree necrosis and/or stricture. Conventional treatment of IA in this setting has required retransplantation. METHODS: A retrospective review of 274 patients (287 OLTx) from September 1991 through September 1996 was performed. Median follow-up was 3.6 years. Diagnosis of HAT was confirmed by arteriography and IA was documented by computerized tomography. Percutaneous drainage of the abscess and stenting of biliary strictures, if present, was achieved using conventional interventional radiology techniques. RESULTS: The diagnosis of hepatic artery complication was made in 14 patients (5.1%), 2 of whom required retransplantation. Hepatic artery thrombosis associated with solitary IA was found in 3 patients (1%) who were transplanted in our center and in 1 additional patient followed up at our center but transplanted elsewhere. All 4 patients had complete resolution of IA using this approach. Three of the 4 patients are alive and well, with the fourth patient succumbing to recurrent hepatitis B infection resulting in allograft failure. CONCLUSIONS: Solitary hepatic allograft abscesses associated with HAT respond to percutaneous drainage and antibiotics, obviating the need for retransplantation in this setting.

Female↗

PubMed1998

Hepatic iron overload: direct HFE (HLA-H) mutation analysis vs quantitative iron assays for the diagnosis of hereditary hemochromatosis.

Among patients with hepatic iron overload, the distinction between hereditary hemochromatosis (HH), a common yet treatable genetic disease, and other causes of siderosis remains problematic. The recent discovery of a specific homozygous mutation (C282Y) in a novel major histocompatibility complex class I-like gene (named HLA-H or HFE) in 80% to 100% of well-characterized cases of HH suggests that direct DNA-based mutation analysis may help resolve this dilemma. To assess the clinical utility of direct HLA-H mutation analysis in a typical diagnostic setting, we measured genotypic and phenotypic parameters of iron overload in 37 subjects with biopsy-proven hepatic siderosis (2+ or greater) and in 127 healthy control subjects. The prevalence of C282Y homozygotes was significantly greater in the hepatic siderosis group (32%) than in the control group (0%), confirming the association between this homozygous mutation and hepatic iron overload. In the hepatic siderosis group, C282Y homozygotes had significantly higher hepatic iron and ferritin levels, a significantly lower prevalence of hepatitis C virus or alcoholic liver disease, but no significant difference in the saturation of serum transferrin. Of the 20 subjects with a hepatic iron index (HII) in the previously defined "hemochromatosis range" (>1.9), 9 (45%) were C282Y homozygotes. Of the 11 nonhomozygous subjects with an HII greater than 1.9 (presumed false-positive HIIs), 10 (91%) had hepatic cirrhosis compared with 3 of 9 (33%) homozygotes with an HII greater than 1.9 who had cirrhosis (P<.02). The HII thus has poor diagnostic specificity for predicting genotypic HH in patients with cirrhosis. We conclude that direct determination of the HLA-H C282Y genotype may be the single best diagnostic test for HH, particularly in patients with cirrhosis, for whom the HII is quite nonspecific.

Adult↗

PubMed1998

Liver transplantation for disulfiram-induced hepatic failure.

Fulminant hepatitis is a rare but potentially fatal adverse reaction that may occur after the use of disulfiram. A patient without a known history of liver disease was transplanted for fulminant hepatic failure secondary to disulfiram. A high index of suspicion and aggressive therapeutic approaches are essential for the prompt diagnosis and treatment of disulfiram-induced hepatic failure. The clinical presentation, histopathology, treatment, and all cases of disulfiram-induced hepatic failure reported in the English literature are reviewed. The role of orthotopic liver transplantation in a case of disulfiram-induced hepatic failure is discussed.

Adult↗

PubMed1997

Cytomegalovirus viremia: risk factor for allograft cirrhosis after liver transplantation for hepatitis C.

BACKGROUND: Despite recent advances in diagnosis and treatment, cytomegalovirus (CMV) infection continues to be a common cause of morbidity in liver transplant (LT) recipients. Because CMV infection suppresses cell-mediated immunity, which seems to be important in neutralizing hepatitis C virus (HCV) infection, we assessed the impact of CMV infection on histopathological HCV recurrence after LT. METHODS: The study group was comprised of 43 consecutive LT recipients with at least 6 months of histologic follow-up. Group 1 consisted of the 8 patients who developed CMV viremia after LT; group 2 comprised the 35 patients without CMV viremia. There was no significant difference with regard to age, initial immunosuppression, incidence of rejection, distribution of HCV genotypes, or mean follow-up between the groups. Semiquantitative histopathologic assessment of allograft hepatitis was performed using the Knodell's score. RESULTS: The mean total Knodell score of the final allograft biopsy was significantly greater in group 1 patients (P=0.016), with most of the difference due to periportal/bridging necrosis (P=0.009) and lobular activity subitem (P=0.01) scores. Half of the CMV viremic patients eventually developed allograft cirrhosis as compared with 11% of the CMV-negative patients (P=0.027). Accordingly, the cirrhosis-free actuarial survival by Kaplan-Meier estimates was significantly diminished in the CMV viremic patients. Glycoprotein B genotype analysis of CMV isolates revealed no significant differences between patients who did and those who did not develop allograft cirrhosis. CONCLUSIONS: After LT for chronic HCV, patients who develop CMV viremia incur a significantly greater risk of severe HCV recurrence.

Antiviral Agents↗

PubMed1997

Immunostaining of the von Hippel-Lindau gene product in normal and neoplastic human tissues.

Alterations in the von Hippel-Lindau (VHL) gene are correlated with a diverse group of neoplasms including hemangioblastoma, clear cell renal carcinoma (RCC), and pheochromocytoma. Molecular genetic studies suggest that VHL is a tumor-suppressor gene; correspondingly, reintroduction of a VHL complementary DNA (cDNA) into RCC cells inhibits their ability to form tumors in nude mice. Recently, it was discovered that the VHL gene product (pVHL) binds to two subunits of the transcription elongation complex Elongin (SIII), resulting in decreased activity of this complex in vitro. It is proposed that pVHL functions in vivo as a negative regulator of transcription elongation; however, the intracellular localization of pVHL has not been clearly delineated. Epitope-tagged pVHL has been observed in either the nucleus or the cytoplasm of cultured cells, depending on the density of the cell culture. In this article, the cellular localization of pVHL in normal and neoplastic human tissues is documented using three different monoclonal antibodies. Strong expression of pVHL was observed in the epithelial cells of all organs examined, particularly in renal tubules, and was exclusively cytoplasmic. Lesser degrees of staining, also cytoplasmic, were observed in other cell types. A variety of carcinomas (lung, prostate, colon, breast, bladder, and thyroid) showed strong cytoplasmic staining for pVHL including four of five sporadic clear cell RCC. Of the nonepithelial neoplasms examined, only one tumor, an embryonal rhabdomyosarcoma, failed to stain for pVHL. The findings establish wide-spread expression of VHL at the protein level and provide strong evidence that most, if not all, pVHL is localized to the cytoplasm of cells in vivo.

Carcinoma↗

PubMed1997

Papillary (chromophil) renal cell carcinoma: histomorphologic characteristics and evaluation of conventional pathologic prognostic parameters in 62 cases.

For more than two decades, papillary renal cell carcinoma has been recognized as a possible distinct clinicopathologic subtype of renal cell carcinoma (RCC). However, the histologic criteria for its diagnosis and the clinical outcome are still debated. In an attempt to clarify the diagnostic criteria and resolve issues pertaining to biologic potential, we have evaluated the histologic spectrum of 62 papillary RCCs and assessed significance of conventional pathologic prognostic parameters (Fuhrrman's nuclear grade [NG], pathologic stage [Robson and TNM], tumor size, multifocality, necrosis, and foam cells) and correlated these with outcome. The mean age of patients was 61.8 years (range 22-83), and males were more commonly affected (1.8:1). Grossly, most tumors were well circumscribed, averaged 6.7 cm in size (range 1.8-18), and were predominantly localized to the renal poles (polar vs. mid-renal, 3:1). Multifocality was a prominent feature (24 cases), and in three cases tumors were bilateral. Microscopically, papillary RCCs were predominantly papillary or tubulopapillary, often with a thick fibrous capsule, foam cells, necrosis, hemorrhage, and multifocality. Thirty-five percent of these tumors were low grade (NG I and II) and 65% high grade (NG III and IV). Sixteen of these tumors presented in a higher stage (stages III and IV), and the overall stage correlated with NG (chi 2, p = 0.009). Tumors were further distinguished by cytoplasmic features: eosinophilic (42%), basophilic (34%) and mixed (24%). Eosinophilic tumors were predominantly high grade, and basophilic tumors low grade (chi 2, p = 0.000). A mean follow-up of 57 months showed progression (metastasis, recurrence, or death due to disease) in 21%, whereas 63% were free of disease. Eleven percent died of unrelated causes, and 5% were lost to follow-up. Kaplan-Meier survival analysis showed that both high NG and stage were strongly associated with decreased survival (p = 0.0000 each), as were decreased foam cell (p = 0.0025) and vascular invasion (p = 0.0002). Comparison of 196 reported cases of papillary RCC, including the current series, with reported large series of conventional RCC indicates that papillary RCC usually presents at an early stage, and stage I (Robson) papillary RCC has better 5 year survival rates (87%-100%) than does RCC of the same stage (65-75%). The overall 5 years survival rate for papillary carcinoma (82-90%) was also higher than that of conventional RCC (44-54%). In a Cox proportional hazard regression model, TNM stage appeared to be the only significant variable (p = 0.0000, hazard ratio 10.1) in predicting outcome among papillary RCC. Based on this experience, we conclude that (a) papillary RCC is a malignant tumor, with a tendency to present at a lower stage, but with a distinct potential for progression and aggressive behavior; (b) stratification of these tumors according to cell type, amount of foam cells, presence or absence of vascular invasion, nuclear grade, and pathologic stage provides useful prognostic information; (c) the better 5-year survival rate of papillary RCC (overall and for stage I tumors) compared with that of conventional RCC suggests that it is a tumor with lower malignant potential. Thus, histologic subcategorization of a renal carcinoma as papillary RCC appears to have prognostic implications.

Adenocarcinoma, Clear Cell↗

PubMed1997

Solid variants of papillary (chromophil) renal cell carcinoma: clinicopathologic and genetic features.

Papillary renal cell carcinomas (RCCs) traditionally have been defined histologically as tumors with at least 50% true papillae. However, these tumors also have characteristic immunohistochemical and genetic features that separate them from other RCCs. We identified six tumors composed of solid sheets of cells without true papillae but that otherwise resembled papillary RCCs, which we feel represent solid variants of papillary RCCs. All six tumors were primary lesions of the kidney, all were strongly reactive for epithelial membrane antigen, cytokeratin 7, and callus keratin, and all were negative for the high molecular weight keratin antibody 34BE12. Four of four tumors tested showed trisomies for chromosome 7, chromosome 17, or both by either cytogenetic analysis or fluorescence in situ hybridization. Four cases were composed of solid sheets of cells containing distinct micronodules that in some cases resembled abortive papillae. The cells composing the micronodules had abundant eosinophilic cytoplasm, open chromatin, and in some cases prominent nucleoli. The intervening cells had similar nuclei, but the amount of cytoplasm was variable. In three of these micronodular cases, multiple tumors diffusely replaced the kidney; in the fourth case two typical clear cell RCCs and a typical papillary RCC were also present in the same kidney, but the micronodular tumor was unifocal. The two remaining cases were solitary tumors consisting of solid sheets of cells forming ill-defined tubules. These cells had scant clear cytoplasm and small round to elongate nuclei with occasional nuclear grooves but only rare small nucleoli. Limited follow-up has shown no evidence of disease in any patient thus far. The differential diagnosis includes "renal adenoma," renal adenomatosis, metanephric adenoma, and clear/granular cell RCC. We conclude that solid variants of papillary RCCs lack true papillae but have characteristic histologic, immunohistochemical, and genetic features.

Adult↗

PubMed1997

Vascular expression of E-selectin is increased in estrogen-receptor-negative breast cancer: a role for tumor-cell-secreted interleukin-1 alpha.

Angiogenesis plays an important role in breast cancer growth and metastasis. Multiple adhesion molecules have been shown to perform critical functions in the process of angiogenesis. In this study, we analyzed 15 benign and 22 malignant estrogen-receptor-negative and estrogen-receptor-positive breast specimens for the presence of the endothelial cell adhesion molecules E-selectin and P-selectin. We found that E-selectin's expression was increased in the malignant breast tumors compared with their benign counterparts (23.86% of blood vessels versus 2.47%; P = 0.0005). Furthermore, E-selectin staining was found to be significantly increased in the estrogen-receptor-negative carcinomas compared with the estrogen-receptor-positive ones (P = 0.005). In vitro findings strongly correlated with the in vivo findings and showed a higher degree of E-selectin induction in endothelial cells exposed to conditioned media from estrogen-receptor-negative breast cancer cell lines than from estrogen-receptor-positive ones. The degree of E-selectin induction correlated with the amount of interleukin-1 alpha in the tumor-conditioned media. Neutralizing antibodies to interleukin-1 alpha significantly inhibited the E-selectin expression in endothelial cells exposed to tumor-conditioned media. The results indicate that the endothelial E-selectin expression during angiogenesis is related to breast carcinoma progression in vivo and that this component of angiogenesis may be due directly to tumor-cell-secreted interleukin-1 alpha.

Breast Neoplasms↗

PubMed1997

Immunohistochemistry of unclassified sex cord-stromal tumors of the testis with a predominance of spindle cells.

Unclassified sex cord-stromal tumors (SCSTs) of the testis comprised predominantly of spindle cells can be difficult to classify. To achieve better definition of these tumors, we examined the histologic, histochemical, and ultrastructural features of four unclassified SCSTs with spindle-cell features, and compared their immunohistochemical features with those of 24 other SCSTs of the testis and ovary. Three of the spindle-cell tumors were composed of relatively short spindled cells with prominent nuclear grooves and intermixed epithelioid cells. All of the three were located adjacent to the rete testis. The fourth case consisted of elongate spindle cells that were reminiscent of smooth muscle. In all of the four cases, reticulin enveloped aggregates of cells of various sizes but not individual cells. Ultrastructural analysis of two of the spindle-cell tumors revealed desmosomes, numerous thin filaments, and focal dense-bodies. Immunohistochemically, all of the four tumors were reactive for S-100 protein and smooth muscle actin. Staining for S-100 protein and smooth muscle actin was also observed in three of six granulosa cell tumors and both juvenile granulosa cell tumors. Although variable staining for S-100 protein was found in 5 of the 12 other SCSTs (4 Leydig cell, 6 Sertoli-Leydig cell, and 2 unclassifiable ovarian SCSTs), reactivity for smooth muscle actin was present in only 1 Sertoli-Leydig cell tumor. In contrast, all of the four ovarian fibromas/thecomas were reactive for smooth muscle actin but failed to stain for S-100 protein. Taken together, the histologic, histochemical, immunohistochemical, and ultrastructural features of the spindle-cell tumors are similar to those of granulosa cell tumors. Reactivity for S-100 protein and smooth muscle actin is characteristic of these tumors. These tumors should be distinguished from other unclassified SCSTs.

Actins↗

PubMed1996

Complex translocation [7;22] identified in an epithelioid hemangioendothelioma.

We describe a malignant epithelioid hemangioendothelioma arising in the back of a 45-year-old man with pulmonary and bone marrow metastases. Light microscopic and immunohistochemical features of this tumor are presented. Karyotyping revealed several clonal abnormalities: a complex unbalanced translocation [7;22] involving multiple breakpoints (confirmed by fluorescence in situ hybridization), a Robertsonian t(14;14), and loss of the Y chromosome. Monosomy for chromosome 11 was noted in a subset of the tumor cells. To our knowledge a karyotype has not been previously reported for this unusual vascular tumor.

Bone Neoplasms↗

PubMed1996

Evaluating early-stage prostate cancer. What pretreatment criteria best guide therapeutic decision making?

Although much has been learned about clinically localized PCa, no single prognostic parameter has been identified that is uniquely reliable in assessing prognosis. The best approach to the newly diagnosed PCa patient remains unchanged: to review all the clinical, radiologic, and histopathologic findings together. In combination, the serum PSA level and the histologic features of a tumor on biopsy can be used to predict the likelihood that a tumor is organ-confined or has spread beyond the gland. By this approach, some patients may be placed into a low-risk category for which "watchful waiting" may be a reasonable option. For other patients, the benefit from this approach is in making more informed decisions concerning definitive therapy and/or the use of adjuvant therapy. The role of the surgical pathologist is to provide as much information as possible regarding the amount, location, and differentiation of tumor present in biopsy and TUR specimens. Prognostic interpretation of these histopathologic findings depends on good communication between pathologists and urologists, oncologists, and radiation oncologists, which remains a cornerstone in therapeutic decision making.

Adenocarcinoma↗

PubMed1996

Papillary renal cell carcinoma: quantitation of chromosomes 7 and 17 by FISH, analysis of chromosome 3p for LOH, and DNA ploidy.

Papillary renal cell carcinoma (papillary RCC) is an uncommon histologic variant of RCC with distinct gross, microscopic, and immunohistochemical features. Recent karyotypic analyses suggest that papillary RCC differs from other types of RCC at the genetic level as well. Whereas nonpapillary (clear cell, granular cell) RCC is characterized by deletions in chromosome 3p, papillary tumors reportedly exhibit a pattern of chromosomal trisomies, typically including chromosomes 7 and 17. To further examine the relationship between overrepresentation of these chromosomes and papillary histology, archival material from 36 papillary tumors was subjected to fluorescence in situ hybridization (FISH) analysis using alpha-satellite repeat probes specific to 7 and 17. Excess signals for chromosome 17 were detected in 22 of 28 (78%) low-grade papillary tumors (Fuhrman nuclear grades 1 and 2), and in seven of eight (87%) high-grade tumors (grades 3 and 4). Correlation of chromosome 17 FISH signals with karyotypes performed on two low-grade and three high-grade tumors was excellent. Among the cases without evidence of excess chromosome 17 were three unusual papillary tumors with sclerotic and hyalinized fibrovascular cores. In two cases, comparison was made of FISH signals from multiple, separate gross nodules of tumor; concordance for trisomic 17 signals was observed in one case, but not in the other. Chromosome 7 signals were overrepresented in all seven papillary tumors examined. DNA ploidy was determined in 19 of the 36 tumors; a relationship between DNA ploidy and polysomy 7 or 17 was not apparent. To examine the possible role of chromosome 3p deletions in the development of papillary RCC, 11 cases were studied for loss of heterozygosity (LOH) at one or more loci in the region of 3p13-21. Only three of the 11 cases had LOH at these loci. The findings are discussed with respect to the development and progression of papillary RCC.

Adult↗

PubMed1996

E-selectin is present in proliferating endothelial cells in human hemangiomas.

E-selectin, an endothelial-cell-specific leukocyte adhesion molecule, may also function in angiogenesis. To investigate its role in a noninflammatory angiogenic disease, E-selectin was analyzed by immunohistochemistry in specimens of proliferative phase and involutive phase hemangiomas. Hemangioma is an endothelial cell tumor of capillary blood vessels that grows rapidly during infancy and regresses spontaneously during childhood. E-selectin expression was high in proliferative phase specimens and was co-localized with dividing microvascular endothelial cells. Relative to the number of blood vessels, E-selectin declined significantly in involutive phase specimens demonstrating that E-selectin correlates with angiogenesis in the tumors. E-selectin was not detected in quiescent endothelium but was co-localized in dividing microvascular endothelial cells in placenta and neonatal foreskin, two tissues with ongoing growth of microvessels. These in vivo studies support the hypothesis that E-selectin functions in angiogenesis and suggest that E-selectin may be a marker for proliferating endothelium.

Antibodies, Monoclonal↗

PubMed1995

High level monocyte chemoattractant protein-1 expression in transgenic mice increases their susceptibility to intracellular pathogens.

We have constructed transgenic mice in which the mouse mammary tumor virus long terminal repeat controls the expression of murine monocyte chemoattractant protein-1 (MCP-1). Several independently derived lines of transgenic mice constitutively expressed MCP-1 protein in a variety of organs. Protein extracts from these organs had substantial in vitro monocyte chemoattractant activity that was neutralized by an anti-MCP-1 Ab, indicating that transgenic MCP-1 protein is biologically active. However, no transgenic mouse at any age displayed monocyte infiltrates in MCP-1-expressing organs. Two transgenic lines had circulating MCP-1 levels of 13 to 26 ng/ml, which is a concentration sufficient to induce maximal monocyte chemotaxis in vitro. These transgenic lines showed a 1 to 1.5 log greater sensitivity to infection with Listeria monocytogenes and Mycobacterium tuberculosis. A third transgenic line had lower serum levels of MCP-1 and was resistant to L. monocytogenes. The results suggest that this transgenic model is one of monocyte nonresponsiveness to locally produced MCP-1 due to either receptor desensitization or neutralization of a chemoattractant gradient by high systemic concentrations of MCP-1. Regardless of the mechanism, the data indicate that constitutively high levels of MCP-1 expression do not induce monocytic infiltrates, and that MCP-1 is involved in the host response to intracellular pathogens.

Animals↗