NUPR1, a new target in liver cancer: implication in controlling cell growth, migration, invasion and sorafenib resistance.

Sorafenib, an oral multikinase inhibitor, is the only approved agent for the treatment of advanced hepatocellular carcinoma (HCC). However, its benefits are modest, and as its mechanisms of action remain elusive, a better understanding of its anticancer effects is needed. Based on our previous study results, we investigated here the implication of the nuclear protein 1 (NUPR1) in HCC and its role in sorafenib treatment. NUPR1 is a stress-inducible protein that is overexpressed in various malignancies, but its role in HCC is not yet fully understood. We found that NUPR1 expression was significantly higher in primary human HCC samples than in the normal liver. Knockdown of NUPR1 significantly increased cell sensitivity to sorafenib and inhibited the cell growth, migration and invasion of HCC cells, both in vitro and in vivo. Moreover, NUPR1 silencing influenced the expression of RELB and IER3 genes. Unsurprisingly, RELB and IER3 knockdown also inhibited HCC cell viability, growth and migration. Using gene expression profiling of HCC cells following stable NUPR1 knockdown, we found that genes functionally involved in cell death and survival, cellular response to therapies, lipid metabolism, cell growth and proliferation, molecular transport and cellular movement were mostly suppressed. Network analysis of dynamic gene expression identified NF-κB and ERK as downregulated gene nodes, and several HCC-related oncogenes were also suppressed. We identified Runt-related transcription factor 2 (RUNX2) gene as a NUPR1-regulated gene and demonstrated that RUNX2 gene silencing inhibits HCC cell viability, growth, migration and increased cell sensitivity to sorafenib. We propose that the NUPR1/RELB/IER3/RUNX2 pathway has a pivotal role in hepatocarcinogenesis. The identification of the NUPR1/RELB/IER3/RUNX2 pathway as a potential therapeutic target may contribute to the development of new treatment strategies for HCC management.

Multifaceted roles of GSK-3 and Wnt/ß-catenin in hematopoiesis and leukemogenesis: opportunities for therapeutic intervention.

Glycogen synthase kinase-3 (GSK-3) is well documented to participate in a complex array of critical cellular processes. It was initially identified in rat skeletal muscle as a serine/threonine kinase that phosphorylated and inactivated glycogen synthase. This versatile protein is involved in numerous signaling pathways that influence metabolism, embryogenesis, differentiation, migration, cell cycle progression and survival. Recently, GSK-3 has been implicated in leukemia stem cell pathophysiology and may be an appropriate target for its eradication. In this review, we will discuss the roles that GSK-3 plays in hematopoiesis and leukemogenesis as how this pivotal kinase can interact with multiple signaling pathways such as: Wnt/ß-catenin, phosphoinositide 3-kinase (PI3K)/phosphatase and tensin homolog (PTEN)/Akt/mammalian target of rapamycin (mTOR), Ras/Raf/MEK/extracellular signal-regulated kinase (ERK), Notch and others. Moreover, we will discuss how targeting GSK-3 and these other pathways can improve leukemia therapy and may overcome therapeutic resistance. In summary, GSK-3 is a crucial regulatory kinase interacting with multiple pathways to control various physiological processes, as well as leukemia stem cells, leukemia progression and therapeutic resistance. GSK-3 and Wnt are clearly intriguing therapeutic targets.

Targeting the leukemic stem cell: the Holy Grail of leukemia therapy.

Since the discovery of leukemic stem cells (LSCs) over a decade ago, many of their critical biological properties have been elucidated, including their distinct replicative properties, cell surface phenotypes, their increased resistance to chemotherapeutic drugs and the involvement of growth-promoting chromosomal translocations. Of particular importance is their ability to transfer malignancy to non-obese diabetic-severe combined immunodeficient (NOD-SCID) mice. Furthermore, numerous studies demonstrate that acute myeloid leukemia arises from mutations at the level of stem cell, and chronic myeloid leukemia is also a stem cell disease. In this review, we will evaluate the main characteristics of LSCs elucidated in several well-documented leukemias. In addition, we will discuss points of therapeutic intervention. Promising therapeutic approaches include the targeting of key signal transduction pathways (for example, PI3K, Rac and Wnt) with small-molecule inhibitors and specific cell surface molecules (for example, CD33, CD44 and CD123), with effective cytotoxic antibodies. Also, statins, which are already widely therapeutically used for a variety of diseases, show potential in targeting LSCs. In addition, drugs that inhibit ATP-binding cassette transporter proteins are being extensively studied, as they are important in drug resistance-a frequent characteristic of LSCs. Although the specific targeting of LSCs is a relatively new field, it is a highly promising battleground that may reveal the Holy Grail of cancer therapy.

Trigeminal neuropathy.

Trigeminal neuropathies (TNs) are well recognized disorders characterized and manifesting as skin and mucosal numbness in the region innervated by the trigeminal nerve. Facial numbness indicates trigeminal sensory alteration affecting the trigeminal system. TNs always pose differential location difficulties as multiple diseases are capable of producing them: they can be the result of traumatism, tumors, or diseases of the connective tissue, infectious or demyelinating diseases, or may be of idiopathic origin. Their importance is explained by the fact that TN may represent the first manifestation of tumor disease, or of relapse in patients with prior neoplastic processes. As such, these manifestations are ominous, and patient life expectancy is often short. The clinical exploration reveals a loss of sensitivity in the cutaneous territory corresponding to the affected nerve, which can be partial (hypoesthesia) or complete (anesthesia). The sensory defect is occasionally associated with hyperesthesia (i.e., the patient suffers a decrease in sensory perception, but when sensation is perceived, it may cause considerable discomfort). Complementary studies are needed to establish the etiologic diagnosis, with laboratory tests to discard the possible causative diseases underlying the trigeminal neuropathy, and the opportune radiographic examinations in the form of plain X-rays or a routine cranial computed tomography scan.

Sex hormones and risk of liver tumor.

The liver is morphologically and functionally modulated by sex hormones. Long-term use of oral contraceptives (OCs) and anabolic androgenic steroids (AASs) can induce both benign (hemangioma, adenoma, and focal nodular hyperplasia [FNH]) and malignant (hepatocellular carcinoma [HCC]) hepatocellular tumors. Hepatic adenomas (HAs) are rare, benign neoplasms usually occurring in young women, the development and the complications of which have been related to the strength of OCs and the duration of their use. HA incidence has fallen since the introduction of pills containing smaller amounts of estrogens. FNH is a benign lesion, most commonly seen in young women, which is thought to represent a local hyperplastic response of hepatocytes to a vascular abnormality. Because of the female predominance and the young age at onset, a role of female hormones has been suggested. Furthermore, a large proportion of women with FNH (50-75%) are OC users. Liver hemangiomas (LHs) are the most common benign liver tumors and are seen more commonly in young adult females. The female predilection and clinical observations of LH growth under conditions of estrogenic exposure suggest a possible role for estrogen in the pathogenesis of LHs. HCC has become one of the most widespread tumors in the world in recent years, representing the sixth leading cancer and the third most common cause of death from cancer. Apart from liver cirrhosis, numerous other factors responsible for its onset have been proposed: hepatitis infections from virus B (HBV) and C (HCV), alcohol, smoking, and aflatoxin. However, regardless of etiology, chronic liver diseases progress at unequal rates in the two sexes, with the major sequelae, such as cirrhosis and HCC, being more frequent in men than in women. These epidemiological data have prompted researchers to investigate the relationship between sex hormones and liver tumors. The human liver expresses estrogen and androgen receptors and experimentally both androgens and estrogens have been implicated in stimulating hepatocyte proliferation and may act as liver tumor inducers or promoters.

Circulating IL-6 and sIL-6R in patients with hepatocellular carcinoma.

Interleukin-6 plays a central role in regulating the immune system, hematopoiesis, and acute phase reaction. It interacts with a receptor complex consisting of a specific ligand-binding protein (IL-6R, gp80) and a signal transduction protein (gp130). In this report, serum levels of IL-6 and a soluble form of the interleukin-6 receptor (sIL-6R) were evaluated in patients with hepatocellular carcinoma. The correlation between IL-6 and sIL-6R values, the stage of hepatocellular carcinoma, and main liver function tests was also studied.

Expression of HIP/PAP mRNA in human hepatoma cell lines.

The present study attempts to shed more light on the role of hepatocarcinoma-intestine-pancreas/pancreatic associated protein (HIP/PAP) in hepatoma cells. We initially examined, by reverse transcription-polymerase chain reaction (RT-PCR), the HIP/PAP transcripts present in human hepatoma cell lines of different origins and with different grades of differentiation and genetic profiles. We also used DNA sequencing analysis to investigate the structure of the HIP/PAP gene. Further investigation is necessary to define the role of HIP/PAP during the development of human hepatocellular carcinoma and to ascertain whether the use of different transcripts is helpful in regulating HIP/PAP expression in transformed liver cells.

Orofacial pain as the sole manifestation of syringobulbia-syringomyelia associated with Arnold-Chiari malformation.

This is a case report of a male patient who presented with orofacial pain for a year as the only manifestation of syringobulbia-syringomyelia associated with Arnold-Chiari malformation. This article places emphasis on the clinical presentation and possible differential diagnoses. The pain was continuous and affected the left side of the face. It was exacerbated by coughing and physical effort, possibly as a consequence of an increase in intracranial pressure. Paroxysmal pain crises developed over this background of continuous pain, compatible with neurogenic trigeminal pain of the left second branch, together with pain episodes similar to cluster headache on the same side. The symptoms were resolved following neurosurgical management with amplification of the foramen magnum.

Circulating E-selectin levels in chronic hepatitis C patients with normal or elevated transaminase before and after alpha-interferon treatment.

E-selectin, an adhesion molecule of the selectin family, is involved in leukocyte adhesion to the endothelium and in the cellular immunological reactions. Expression of this molecule, in fact, is physiologically absent, but it becomes evident on sinusoidal lining cells during inflammatory liver disease. The aim of this study was to evaluate the behavior of E-selectin in chronic hepatitis C (CH-C) patients with persistently normal transaminase in comparison to patients with CH-C and elevated transaminase, and its changes during alpha-interferon therapy. Immunohistochemical localization of E-selectin was also performed on liver tissue specimens of both groups. Fifty-eight subjects were divided into 3 groups: group A included 18 patients with CH-C and persistently normal transaminase; group B 20 patients with CH-C and persistently elevated transaminase levels and group C included 20 healthy subjects, representing the control group. The first two groups were treated with r-IFN alpha at a dose of 6 MU 3 times a week for 3 months and followed-up with 3 MU 3 times a week for another 3 months. Serum baseline values of E-selectin in groups A and B were significantly higher than those in group C (P < 0.04), but there was no difference between groups A and B. Furthermore, there was a trend toward higher E-selectin values as histological severity increased (r = 0.69; P < 0.0001). Post-treatment E-selectin serum values showed a moderate decrease in both groups, but only among responder patients; while E-selectin levels were unchanged in non responders. Immunohistochemical localization showed no staining for E-selectin in normal liver specimens, while there was a quite similar staining for E-selectin in the two groups of patients. In conclusion, this study shows that serum E-selectin levels in patients with CH-C and persistently normal transaminase are higher than in controls and they are associated with severity of liver disease. Liver of these patients express E-selectin molecules, suggesting an activation of the immune system almost identical to that of patients with CH-C and elevated transaminase. In both groups only responder patients showed a moderate decrease below baseline serum values.

Downregulation of wild-type beta-catenin expression by interleukin 6 in human hepatocarcinoma HepG2 cells: a possible role in the growth-regulatory effects of the cytokine?

We investigated the antitumour effects of interleukin 6 (IL-6) on hepatocarcinoma HepG2 cells, endowed with high levels of a mutated, non-degradable, beta-catenin. IL-6 produced minimal growth-inhibitory effects and no apoptosis or gross changes in cell adhesion. Interestingly, however, it caused a consistent decrease in the cytoplasmic levels of wild-type, but not of mutated, beta-catenin protein. There was no effect on E-cadherin or gamma-catenin and a reduction in alpha-catenin occurred only at high concentrations. IL-4, a non-related cytokine, did not modify the content of beta-catenin. IL-6 did not influence beta-catenin mRNA levels. LiCl, a potent inhibitor of Glycogen Synthase Kinase 3beta (GSK3beta) activity, abrogated the IL-6-induced inhibition of wild-type beta-catenin. This indicates that IL-6 can affect wild-type beta-catenin through a post-transcriptional mechanism, probably involving degradation of the protein. This effect might be related to the growth-regulatory activities of IL-6 in other situations, but can not counteract the oncogenic expression of mutated beta-catenin in HepG2 cells or possibly in other tumour cells with similar gene mutations.

Localization and association to cytoskeleton of COLL1alpha mRNA in Paracentrotus lividus egg requires cis- and trans-acting factors.

COLL1alpha mRNA is asymmetrically distributed in the Paracentrotus lividus egg. Here we examine the involvement of the cytoskeleton in the localization process of collagen mRNA. The use of drugs such as colchicine and cytochalasin B reveals a perturbation of localization collagen mRNA. Moreover, the presence of specific cis-and trans-acting factors involved in cytoskeleton binding and the localization process was investigated. By Northwestern experiment we found that the 3'UTR of COLL1alpha mRNA is also able to bind two proteins of 54 and 40 kDa in a cellular fraction containing the cytoskeleton. Finally, we found that the protein of 54 kDa is LP54, a protein that binds the 3'UTRs of P. lividus maternal bep messengers and is necessary for their localization.

Spontaneous cytotoxic activity of eosinophilic granule cells separated from the normal peritoneal cavity of Dicentrarchus labrax.

In this study the spontaneous in vitro cytotoxic activity to tumour cell lines, (K562), by unstimulated sea bass (Dicentrarchus labrax) leukocytes was examined by trypan blue exclusion test and lactate dehydrogenase release assay. A high anti-tumour cell line activity of resident peritoneal leukocytes was found at an effector to target ratio (E:T) of 25:1 after incubation for 2 h at 18 degrees C. Rabbit and sheep erythrocytes were not lysed. A low activity was displayed by head kidney and spleen cell populations whereas blood leukocytes revealed no significant activity. The effect of E:T ratio on cytotoxicity as well as microscopy observations suggested that the cytotoxic reaction required effector-target cell contact. Eosinophilic granule cells, isolated on a Percoll density gradient from a peritoneal wash, appeared to be responsible for the in vitro cytotoxic activity.

Serum concentration of E-selectin in patients with chronic hepatitis, liver cirrhosis and hepatocellular carcinoma.

OBJECTIVES: High levels of soluble E-selectin have been reported in acute and chronic inflammatory disorders. Moreover, in some types of tumor elevated values have been found while in other types reduced levels have been reported. Our aims were to determine whether soluble E-selectin levels might be useful in monitoring the progression of chronic liver disease, including hepatocellular carcinoma. METHODS: Circulating soluble E-selectin was measured by an enzyme-linked immunosorbent assay in the sera of 18 patients with chronic hepatitis, 44 with liver cirrhosis, and 38 with hepatocellular-carcinoma-associated liver cirrhosis. Immunohistochemical localization of E-selectin was also performed on liver tissue specimens of patients with chronic hepatitis, liver cirrhosis and hepatocellular carcinoma. RESULTS: Serum levels of soluble E-selectin were higher in the chronic hepatitis and liver cirrhosis patients than in the hepatocellular carcinoma patients and healthy controls. Levels in the hepatocellular carcinoma patients and controls were not significantly different. In the liver cirrhosis group, divided according to the Child-Pugh classification, soluble E-selectin decreased with disease severity. Similarly, in patients with liver cirrhosis who developed hepatocellular carcinoma, soluble E-selectin decreased as the disease progressed. Immunohistochemical localization showed strong membrane staining on endothelial cells in areas rich in inflammatory cells in severe chronic hepatitis. In some hepatocellular carcinoma tissues a marked E-selectin staining was observed on endothelial cells of tumor-associated small vessels. CONCLUSIONS: The results obtained suggest that high serum levels of soluble E-selectin are associated with chronic hepatitis and liver cirrhosis, and that levels decrease in liver cirrhosis patients as the disease progresses. Patients with hepatocellular carcinoma have different types of soluble E-selectin behaviour the significance of which requires further investigation.

Phosphorylation-dependent regulation of skeletogenesis in sea urchin micromere-derived cells and embryos.

Sea urchin embryo micromeres when isolated and cultured in vitro differentiate to produce spicules. Although several authors have used this model, almost nothing is known about the signaling pathways responsible for initiating skeletogenesis. In order to investigate the potential involvement of phosphorylation events in spiculogenesis, the effect of inhibitors of protein kinases and phosphatases on skeleton formation was studied. Results obtained using both cultured micromeres and embryos revealed that protein tyrosine kinase and phosphatase inhibitors blocked skeleton formation, but not serine/threonine phosphatase inhibitors. The inhibitors showed a dose-dependent effect and when removed from micromere or embryo culture, spicule formation resumed. Inhibition of tyrosine phosphatases resulted in an increase in the tyrosine phosphorylation level of two major proteins and a modest decrease in the expression of the mRNA coding for type I fibrillar collagen. These findings strongly suggest that tyrosine phosphorylation and dephosphorylation is required for micromere differentiation and for normal skeletogenesis during sea urchin embryo development.

[Acute respiratory insufficiency as initial manifestation of brain stem lesions]. / Insuficiencia respiratoria aguda como primera manifestación de lesiones del tronco cerebral.

We describe three patients with different brainstem lesions (bulbar angioma, bulbar infarct, and Arnold-Chiari malformation) who debuted with acute respiratory insufficiency. Other neurological manifestations had gone unobserved in all three cases. Respiratory insufficiency worsened notably during sleep to the point that mechanical ventilation was required or death occurred (Ondine s curse). The patient with a bulbar angioma is stable with only assisted ventilation by a nasal route at night, with good quality of life. Our conclusions are that: a) central nervous system anomalies need to be investigated as possible causes of respiratory insufficiency when lungs are normal; b) the respiratory control of patients with brainstem lesions should be studied, particularly at night (polysomnography), and c) even when awake-state ventilation is adequate, nighttime assisted ventilation may be required.

[Pseudoneurologic conversion and factitious disorders: differential diagnosis in 2 clinical cases]. / Trastornos seudoneurológicos de conversión y facticios: diagnóstico diferencial a través de dos casos clínicos.

The recognition and differentiation of conversion and factitious disorders could be difficult when they coexist with physical problems and their psychopathology is not evident. We present two illustrative cases of patients who share the existence of neurological disorders and present a similar psychiatric semiology, which is phenomenologically different related with their physical deficits. The psychopathological assessment was made by means of a standardized instrument for diagnosis (SCAN) and suitable paraclinical techniques for each case. The test MMPI (Minnesota Multiphasic Personality Inventory) was used in both cases, and an exploration with Thiopental was carried out in one of them. The pertinent differential diagnosis, the advantages of coordinated interdisciplinary interventions in order to elucidate these mental disorders, and the convenience of using appropriated psychometric instruments and exploratory methods are expounded in the present paper.

Spatial distribution of collagen type I mRNA in Paracentrotus lividus eggs and embryos.

We have identified the presence of type I collagen (COLL1alpha) mRNA in Paracentrotus lividus unfertilized egg, indicating a maternal origin of this mRNA. By in situ whole mount hybridization the spatial distribution of COLL1alpha mRNA in egg and embryo at different developmental stages was established. Moreover, the presence of COLL1alpha gene in Paracentrotus lividus genome was analyzed by Southern blot experiments. The localization pattern indicates that the maternal mRNA is placed in the fertilized egg in a fixed position, relative to the embryonic axes. Furthermore, the embryonic expression is spatially restricted during development, suggesting involvement in sea urchin embryo cell specification events. The presence of two bands in Southern blot hybridization may indicate that two genes specific for COLL1alpha are present in the sea urchin genome.

Circulating intercellular adhesion molecule-1 in patients with hepatocellular carcinoma.

BACKGROUND: Intercellular adhesion molecule-1 (ICAM-1) is thought to play an important role in cellular immunological reactions. Expression can be induced by inflammatory cytokines in a wide variety of cells, including hepatocytes. OBJECTIVE: To compare the behaviour of ICAM-1 in liver diseases. PATIENTS AND METHODS: We assayed serum ICAM-1 (sICAM-1) in patients with hepatocellular carcinoma-associated liver cirrhosis, and compared them with a group of cirrhotic patients and controls. sICAM-1 values were also correlated with some biochemical parameters of liver function. Moreover, immunohistochemical localization of ICAM-1 was performed on liver tissue sections of patients with hepatocellular carcinoma, liver cirrhosis and a sample of normal liver. RESULTS: sICAM-1 levels were significantly higher in the hepatocellular carcinoma patients than in controls (P < 0.0001) and the cirrhosis group (P < 0.001). sICAM-1 values directly correlated with alanine aminotransferase, total bilirubin, alkaline phosphatase and gamma-glutamyltranspeptidase serum values (P < 0.05), with an inverse correlation with albuminaemia values (P < 0.05). There was no correlation with alpha-fetoprotein values, but sICAM-1 values were higher in hepatocellular carcinoma patients with large tumours (> 3 cm) than in those with small tumours (< 3 cm) (P < 0.04). Immunohistochemical localization of ICAM-1 was negative in normal liver tissue; positive staining for endothelial cells was found in chronic liver disease, while in hepatocellular carcinoma tissues, positive membrane staining was observed in hepatocytes and, to a lesser extent, at the cytoplasmic level. CONCLUSION: These results suggest that high serum levels of sICAM-1 are associated with severe liver disease, such as liver cirrhosis and hepatocellular carcinoma, and that they tend to increase with deteriorating hepatic function and tumour size.

Expression of PSA-N-CAM in human neuroblastoma cells induced to neuronal differentiation by retinoic acid.

The neural cell adhesion molecule (N-CAM) plays a significant role in the development of the nervous system. Three different isoforms of the molecule have been described, with molecular masses of 180, 140 and 120 kDa, whose differential expression in neurons seems to be related to their state of differentiation. We took advantage of the use of the human neuroblastoma cell line LAN-5, which can be differentiated in vitro by retinoic acid (RA) into neuronal cells, for studying the expression of N-CAM isoforms, and their polysialic acid (PSA) content, at the protein and mRNA levels. Anti-N-CAM polyclonal antibodies recognizing all the N-CAM isoforms and a monoclonal antibody recognizing PSA were used in Western blot experiments with extracts from undifferentiated and RA-differentiated cells. We found that undifferentiated cells express very little of the 180 kDa N-CAM isoform and a large amount of the 140 kDa isoform. A 4-fold increase in the expression of the 180 kDa N-CAM isoform was obtained when LAN-5 cells were differentiated by RA for 8 days, whereas a 1.8-fold increase in the expression of the 140 kDa N-CAM isoform was observed upon differentiation. Similarly, the levels of the 7.4 kb mRNA coding for N-CAM 180 kDa, determined by Northern blot analysis, were barely detectable in undifferentiated cells, and showed a 3.8-fold increase upon differentiation. By contrast, only a 1.3-fold increase in the 6.7 kb mRNA, coding for the 140 kDa N-CAM isoform, was observed. N-CAM was always found in its polysialylated form in both undifferentiated and RA-differentiated cells. This indicates that, in LAN-5 cells, the expression and activity of the polysialytransferase enzyme precedes the acquisition of a neuronal phenotype.