Hereditary angio-oedema with mesangiocapillary glomerulonephritis

A patient with hereditary angio-oedema (HAO) developed mesangiocapillary glomerulonephritis (MCGN) under observation. HAO is characterized by an inherited defect of complement-deficiency of C1 esterase. MCGN is often associated with another complement abnormality which leads to depression of serum C3 and there is some evidence that the complement abnormality precedes the nephritis. The coincidence of these two rare diseases in the present patient, and in one previously described, suggests that other complement abnormalities may predispose to the development of MCGN.     

Lymphoplasmacytic sclerosing pancreatitis

Lymphoplasmacytic sclerosing pancreatitis is a rare entity that has been described under many different names and constitutes a diagnostic challenge as it may simulate a neoplastic process. Herein, we report a case of a 61-year-old woman who presented to our institution complaining of left flank pain and was found to have normal levels of amylase and lipase. An abdominal magnetic resonance image showed thickening of the pancreatic tail and compression of the pancreatic duct. The radiographic differential included both chronic pancreatitis and a neoplastic process. She underwent an exploratory laparotomy, during which a pancreatectomy and splenectomy were performed. Grossly, the pancreas contained a yellowish white, firm homogeneous mass measuring 6.5 x 3.3 x 2.9 cm involving the entire pancreatic tail and hilum of the spleen. Histologically, pancreatic sections showed extensive fibrosis admixed with an inflammatory infiltrate. This infiltrate was composed mainly of lymphocytes with multiple germinal centers, as well as plasma cells and eosinophils that surrounded pancreatic ducts and extended into the peripancreatic adipose tissue. No malignancy was identified, and the process was diagnosed as lymphoplasmacytic sclerosing pancreatitis.     

Duodenal gangliocytic paraganglioma: a radiological-pathological correlation

Duodenal gangliocytic paraganglioma is a rare tumor that characteristically occurs in the second portion of the duodenum and typically presents with gastrointestinal bleeding. Gangliocytic paragangliomas have a characteristic triphasic microscopic appearance with epithelioid cells, spindle cells, and ganglion cells, resulting in a complex histology with features of paraganglioma, carcinoid, and ganglioneuroma. Duodenal gangliocytic paragangliomas have an excellent prognosis after surgical resection but metastatic spread to regional lymph nodes and recurrence may rarely occur. We report a case of duodenal gangliocytic paraganglioma and discuss the radiological and pathological differential diagnosis of this rare entity.     

Ependymal denudation and alterations of the subventricular zone occur in human fetuses with a moderate communicating hydrocephalus

In mutant rodents, ependymal denudation occurs early in fetal life, preceding the onset of a communicating hydrocephalus, and is a key event in the etiology of this disease. The present investigation was designed to obtain evidence whether or not ependymal denudation occurs in 16- to 40-week-old human fetuses developing a communicating hydrocephalus (n = 8) as compared to fetuses of similar ages with no neuropathologic alterations (n = 15). Sections through the walls of the cerebral aqueduct and lateral ventricles were processed for lectin binding and immunocytochemistry using antibodies against ependyma, astroglia, neuroblasts, and macrophages markers. Anticaveolin was used as a functional marker of the fetal ependyma. The structural and functional molecular markers are differentially expressed throughout the differentiation of the human fetal ependyma. Denudation of the ependyma of the aqueduct and lateral ventricles occurred in all fetuses developing a communicating hydrocephalus, including the youngest ones studied. The denuded surface area increased in parallel with the fetus age. The possibility is advanced that in many or most cases of human fetal hydrocephalus there is a common defect at the ependymal cell lineage leading to ependymal detachment. Evidence was obtained that in hydrocephalic human fetuses a process to repair the denuded areas takes place during the fetal life. In hydrocephalic fetuses, detachment of the ependyma of the lateral ventricles resulted in the (i) loss of the germinal ependymal zone, (ii) disorganization of the subventricular zone and, (iii) abnormal migration of neuroblasts into the ventricular cavity. Thus, detachment of the ependymal layer in hydrocephalic fetuses would not only be associated with the pathogenesis of hydrocephalus but also to abnormal neurogenesis.     

Expression of the nucleoside-derived drug transporters hCNT1, hENT1 and hENT2 in gynecologic tumors

Deoxynucleoside analogs are used in the treatment of a variety of solid tumors. Their transport across the plasma membrane may determine their cytotoxicity and thus nucleoside transporter (NT) expression patterns may be of clinical relevance. Lack of appropriate antibodies for use in paraffin-embedded biopsies has been a bottleneck to undertake high-throughput analysis of NT expression in solid tumors. Here we report the characterization of 2 new antibodies raised against the low-affinity equilibrative NTs, hENT1 and hENT2, suitable for that purpose. These 2 antisera, along with a previously characterized antibody that specifically recognizes the high-affinity Na-dependent concentrative NT, hCNT1, have been used to analyze, using a tissue array approach, NT expression in gynecologic cancers (90 ovarian, 80 endometrial and 118 uterine cervix carcinomas). Human CNT1 was not detected in 33% and 39% of the ovarian and uterine cervix carcinomas, respectively, whereas hENT1 and hENT2 expression was significantly retained in a high percentage of tumors (91% and 96% for hENT1, 84% and 98% for hENT2, in ovarian and cervix carcinomas, respectively). Only a few endometrial carcinomas (15%) were found to be negative for hCNT1, but they all retained hENT1 and hENT2 expression. In ovarian cancer, the loss of all 3 NT proteins was a more common event in the clear cell histologic subtype than in the serous, mucinous and endometrioid histotypes. In uterine cervix tumors, the loss of expression of hCNT1 was significantly associated with the adenocarcinoma subtype. In summary, hCNT1 was by far the isoform whose expression was most frequently reduced or lost in the 3 types of gynecologic tumors analyzed. Moreover, NT expression is related to the type of gynecologic tumor and its specific subtype, hCNT1 protein loss being highly correlated with poor prognosis histotypes. Since hCNT1, hENT1 and hENT2 recognize fluoropyrimidines as substrates, but with different affinities, this study anticipates high variability in drug uptake efficiency in solid tumors.     

Mitochondrial proliferation during apoptosis induced by anticancer agents: effects of doxorubicin and mitoxantrone on cancer and cardiac cells

Doxorubicin is one of the most largely prescribed antitumor drug for the treatment of breast, liver and colon cancers as well as leukemia, but the cardiotoxicity of this anthracycline derivative limits its clinical use. Although doxorubicin is toxic to both cancer and cardiac cells, there are evidences suggesting that the mechanism of cell death is different for the two cell types. To investigate further this issue, we have compared the proapoptotic effects of doxorubicin and the functionally related anthracenedione compound mitoxantrone, which is also used in the clinic for the treatment of cancer. After evaluating the toxicity of the two drugs to mammary adenocarcinoma MTLn3 cells and H9C2 cardiomyocytes, we dissected the drug-induced apoptotic machinery by measuring the effects on the cell cycle progression, DNA condensation and fragmentation, production of endogenous peroxides and caspase activation. Both doxorubicin and mitoxantrone are potent inducers of apoptosis in H9C2 cardiomyocytes and MTLn3 breast cancer cells, but there are significant differences between the two cell types in terms of kinetics and order of the events. In particular, flow cytometry measurements of drug-induced changes in mitochondrial transmembrane potential and mitochondrial mass with different fluorescent probes suggested that the two drugs induced a progressive increase in mitochondrial mass in the cancer cells but not in the cardiac cells. The hypothesis was validated by means of electron microscopy, which revealed a significant increase in the number of mitochondria in drug-treated MTLn3 but not in H9C2 cells. The mitochondrial proliferation precedes the nuclear apoptosis in doxorubicin-treated MTLn3 cells. The changes in the architecture and number of mitochondria are linked to the drug-induced perturbation of the cell cycle progression and apoptosis. The proliferation of mitochondria could explain the higher toxicity of doxorubicin to cancer cells compared to cardiac cells and this suggests novel therapeutic opportunities to better control the cardiotoxicity of anthracyclines.