R. Gentile

Cholangiocarcinoma: Update and future perspectives

Cholangiocarcinoma is commonly considered a rare cancer. However, if we consider the hepato-biliary system a single entity, cancers of the gallbladder, intra-hepatic and extra-hepatic biliary tree altogether represent approximately 30% of the total with incidence rates close to that of hepatocellular carcinoma, which is the third most common cause of cancer-related death worldwide. In addition, cholangiocarcinoma is characterized by a very poor prognosis and virtually no response to chemotherapeutics; radical surgery, the only effective treatment, is not frequently applicable because late diagnosis. Biomarkers for screening programs and for follow-up of categories at risk are under investigation, however, currently none of the proposed markers has reached clinical application. For all these considerations, cancers of the biliary tree system should merit much more scientific attention also because a progressive increase in incidence and mortality for these cancers has been reported worldwide. This manuscript deals with the most recent advances in the epidemiology, biology and clinical presentation of cholangiocarcinoma.

Intra-hepatic and extra-hepatic cholangiocarcinoma: New insight into epidemiology and risk factors

Cholangiocarcinoma (CCA) is a malignant tumour that arises from biliary epithelium at any portion of the biliary tree. CCA is currently classified as intra-hepatic or extra-hepatic CCA (EH-CCA). Recent evidences suggest that intra-hepatic CCA (IH-CCA) and EH-CCA are biologically different cancers, giving further support to a number of recent epidemiological studies showing large differences in terms of incidence, mortality and risk factors. The purpose of this manuscript is to review recent literature dealing with the descriptive epidemiology and risk factors of CCA with a special effort to compare IH- with EH-CCA.

Technetium-99m sestamibi single-photon emission tomography detects subclinical myocardial perfusion abnormalities in patients with systemic lupus erythematosus

Abstract. In patients with systemic lupus erythematosus, involvement of the cardiovascular system is the third leading cause of death. However, although autopsy studies have demonstrated a high incidence of abnormalities in both the myocardium and coronary vessels, clinical manifestations have been reported in only a small percentage of cases. The aim of this study was to evaluate myocardial perfusion in asymptomatic lupus patients using technetium-99m sestamibi single-photon emission tomography (SPET). Twenty-eight patients without overt cardiac involvement and risk factors were studied with 99mTc-sestamibi SPET at rest and after dipyridamole infusion. Perfusion abnormalities were detected in 18 cases: six had persistent defects, three had reversible defects, seven had both persistent and reversible defects, and two showed rest defects which normalized on dipyridamole images (”reverse redistribution pattern”). Coronary angiography was performed in eight patients with positive 99mTc-sestamibi SPET, and showed normal epicardial vessels in all the cases. These results indicate that 99mTc-sestamibi SPET reveals a high prevalence (18 out of 28 patients in this study, i.e. 64%) of myocardial perfusion abnormalities in asymptomatic lupus patients, probably due to the primary immunological damage of this autoimmune disease. In conclusion, rest/dipyridamole 99mTc-sestamibi SPET can be a useful non-invasive method to identify subclinical myocardial involvement in systemic lupus erythematosus, and patients potentially at risk of later cardiac events.

Evidence for multipotent endodermal stem/progenitor cell populations in human gallbladder

BACKGROUND & AIMS Multipotent stem/progenitor cells are found in peribiliary glands throughout human biliary trees and are able to generate mature cells of hepato-biliary and pancreatic endocrine lineages. The presence of endodermal stem/progenitors in human gallbladder was explored. METHODS Gallbladders were obtained from organ donors and laparoscopic surgery for symptomatic cholelithiasis. Tissues or isolated cells were characterized by immunohistochemistry and flow cytometry. EpCAM+ (Epithelial Cell Adhesion Molecule) cells were immunoselected by magnetic microbeads, plated onto plastic in self-replication conditions and subsequently transferred to distinct serum-free, hormonally defined media tailored for differentiation to specific adult fates. In vivo studies were conducted in an experimental model of liver cirrhosis. RESULTS The gallbladder does not have peribiliary glands, but it has stem/progenitors organized instead in mucosal crypts. Most of these can be isolated by immune-selection for EpCAM. Approximately 10% of EpCAM+ cells in situ and of immunoselected EpCAM+ cells co-expressed multiple pluripotency genes and various stem cell markers; other EpCAM+ cells qualified as progenitors. Single EpCAM+ cells demonstrated clonogenic expansion ex vivo with maintenance of stemness in self-replication conditions. Freshly isolated or cultured EpCAM+ cells could be differentiated to multiple, distinct adult fates: cords of albumin-secreting hepatocytes, branching ducts of secretin receptor+ cholangiocytes, or glucose-responsive, insulin/glucagon-secreting neoislets. EpCAM+ cells transplanted in vivo in immune-compromised hosts gave rise to human albumin-producing hepatocytes and to human Cytokeratin7+ cholangiocytes occurring in higher numbers when transplanted in cirrhotic mice. CONCLUSIONS Human gallbladders contain easily isolatable cells with phenotypic and biological properties of multipotent, endodermal stem cells.

Multipotent stem/progenitor cells in the human foetal biliary tree

BACKGROUND & AIMS Biliary tree, liver, and pancreas share a common embryological origin. We previously demonstrated the presence of stem/progenitor cells of endodermal origin in the adult human extrahepatic biliary tree. This study evaluated the human foetal biliary trees as sources of stem/progenitor cells of multiple endodermal-derived mature fates. METHODS Human foetal intrahepatic and extrahepatic biliary tree tissues and isolated cells were tested for cytoplasmic and surface markers of stem cells and committed progenitors, as well as endodermal transcription factors requisite for a liver versus pancreatic fate. In vitro and in vivo experiments were conducted to evaluate the potential mature fates of differentiation. RESULTS Foetal biliary tree cells proliferated clonogenically for more than 1 month on plastic in a serum-free Kubota medium. After culture expansion, cells exhibited multipotency and could be restricted to certain lineages under defined microenvironments, including hepatocytes, cholangiocytes, and pancreatic islet cells. Transplantation of foetal biliary tree cells into the livers of immunodeficient mice resulted in effective engraftment and differentiation into mature hepatocytes and cholangiocytes. CONCLUSIONS Foetal biliary trees contain multipotent stem/progenitor cells comparable with those in adults. These cells can be easily expanded and induced in vitro to differentiate into liver and pancreatic mature fates, and engrafted and differentiated into mature cells when transplanted in vivo. These findings further characterise the development of these stem/progenitor cell populations from foetuses to adults, which are thought to contribute to liver and pancreas organogenesis throughout life.

Lupus Carditis: Evaluation with Technetium-99m MIBI Myocardial SPECT and Heart Rate Variability:

The objective of this paper was to investigate the incidence of myocardial perfusion defects in patients with systemic lupus erythematosus (SLE) associated with dysauto nomic alterations. Twenty patients without any sign or symptoms of heart disease, selected from a larger population of patients with SLE, underwent technetium-99m sestamibi (Tc-99m MIBI) single photon emission computed tomography (SPECT), at rest and after dipyridamole infusion; they also underwent heart rate variability (HRV) exam ination by a 24 hour ambulatory electrocardiography, analyzing in the time domain the standard deviation of the R-R intervals average (SDNN) and the percentage of R-R adjacent intervals differing from each other more than 50 msec (pNN50); in the frequency domain the low (LF) and high frequencies (HF) were analyzed. Twenty healthy volunteers served as control group for heart rate variability. At MIBI-SPECT examina- tion, the scan was found abnormal in 15 patients and normal in five: three patients demonstrated reversible defects in the anteroseptal region, four had irreversible defects in a region (two in the anteroseptal region and two in the lateral region), two had rest defects in two different regions (lateral and inferior, lateral and anteroseptal) that improved during dipyridamole scan, and six had both reversible and irreversible defects: four in a single segment (three anteroseptal and one lateral, and two in two different regions, particularly anteroseptal and lateral, lateral and inferior). All 20 patients showed significantly lower HRV parameters in comparison with the control group, except for pNN50, which indicates decreased physiologic periodic fluctuations of the autonomic nervous system. In six patients who underwent coronary angiography, the epicardial vessels were found completely normal. In view of the high incidence of myocardial hypoperfusion in patients with HRV alterations, the authors hypothesize that autonomic dysfunction may be associated with microvascular disease or metabolic alteration. They also believe that MIBI scintigraphy is a suitable technique in detecting myocardial damage in SLE patients free of clinical manifestation.

Cholangiocarcinoma: increasing burden of classifications.

Cholangiocarcinoma (CCA) is a very heterogeneous cancer from any point of view, including epidemiology, risk factors, morphology, pathology, molecular pathology, modalities of growth and clinical features. Given this heterogeneity, a uniform classification respecting the epidemiologic, pathologic and clinical needs is currently lacking. In this manuscript we discussed the different proposed classifications of CCA in relation with recent advances in pathophysiology and biology of this cancer.

An oestrogen receptor β-selective agonist exerts anti-neoplastic effects in experimental intrahepatic cholangiocarcinoma

BACKGROUND Cholangiocarcinoma cells over-express oestrogen receptor-β, which displays anti-proliferative and pro-apoptotic effects. AIM To evaluate the effects of a newly developed and highly selective oestrogen receptor-β agonist (KB9520) on experimental intrahepatic cholangiocarcinoma. METHODS In vitro, the effects of KB9520 on apoptosis and proliferation of HuH-28 cells, HuH-28 cells with selective oestrogen receptor-β silencing (by small interfering RNA), HepG2 cells (oestrogen receptor-α and oestrogen receptor-β negative) and HepER3 cells (HepG2 cells transformed to stably express oestrogen receptor-α) were evaluated. In vivo, the effects of KB9520 on experimental intrahepatic cholangiocarcinoma, induced by thioacetamide administration were tested. RESULTS In vitro, KB9520 induced apoptosis and inhibited proliferation of HuH-28 cells. KB9520 effects were absent in cells lacking oestrogen receptor-α and β (HepG2) and in cells expressing only oestrogen receptor-α (HepER3); its pro-apoptotic effect was impaired in cells where oestrogen receptor-β expression was decreased by specific small interfering RNA. In vivo, KB9520 inhibited experimental intrahepatic cholangiocarcinoma development in thioacetamide-treated rats and promoted tumour regression in rats where tumour was already established. In treated animals, tumour areas showed reduced proliferation but increased apoptosis. CONCLUSIONS KB9520 induced apoptosis in cholangiocarcinoma by selectively acting on oestrogen receptor-β, suggesting that oestrogen receptor-β selective agonists may be a novel and effective therapeutic option for the medical treatment of intrahepatic cholangiocarcinoma.

The fetal liver as cell source for the regenerative medicine of liver and pancreas.

Patients affected by liver diseases and diabetes mellitus are in need for sources of new cells to enable a better transition into clinic programs of cell therapy and regenerative medicine. In this setting, fetal liver is becoming the most promising and available source of cells. Fetal liver displays unique characteristics given the possibility to isolate cell populations with a wide spectrum of endodermal differentiation and, the co-existence of endodermal and mesenchymal-derived cells. Thus, the fetal liver is a unique and highly available cell source contemporarily candidate for the regenerative medicine of both liver and pancreas. The purpose of this review is to revise the recent literature on the different stem cells populations isolable from fetal liver and candidate to cell therapy of liver diseases and diabetes and to discuss advantages and limitation with respect to other cell sources.

Echocardiographic evaluation of left ventricular outflow tract obstruction in complete transposition of the great arteries

Subpulmonic stenosis in complete d-transposition of the great arteries (d-TGA) is a frequently associated malformation, the precise diagnosis of which is essential for optimal medical and surgical treatment. Sixteen patients with d-TGA and subpulmonic stenosis have been studied by M-mode and two-dimensional (2DE) echocardiography and cardiac catheterization. Dynamic obstruction was found in six patients and fixed stenosis in 10. Systolic anterior motion of the mitral valve without fixed obstruction of the left ventricular outflow tract (LVOT) was present in patients with dynamic stenosis. Measurements of left ventricular end-diastolic posterior wall thickness to minor semiaxis ratio correlated well (p less than 0.001) with the pressure gradient across the LVOT. Various types of anatomic fixed obstruction are described. M-mode echocardiography provides assessment of dynamic obstruction but does not allow quantitative evaluation of the length of the narrowed segment. The latter can be achieved by 2DE, which offers improved definition of different anatomic types.