Vincenzo Esposito

Prognostic value of p53 in non-small cell lung cancer: Relationship with proliferating cell nuclear antigen and cigarette smoking

p53 mutations are among the most frequent genetic alterations reported in human lung cancer. Although the prognostic value of altered p53 expression is still debated, it is accepted widely that estimation of the proliferation rate has an important prognostic role. Moreover, an association between certain types of human lung cancers and tobacco use is well known. Drawing from this background, we investigated the immunohistochemical expression of mutant oncogenic p53 protein, and related it to the smoking history of 61 patients with non-small cell lung carcinoma (NSCLC) and to the expression pattern of proliferating cell nuclear antigen (PCNA), which is considered to be an important negative prognostic factor in several neoplasms. We found p53 overexpression in 22 (36.1%) specimens, including 16 squamous carcinomas (41%) and six (27.2%) adenocarcinomas. PCNA nuclear staining was detected in 98.4% of the specimens, and a significantly higher PCNA expression score was found in all of the p53-positive samples. When the patient survival time was compared, p53 accumulation had a statistically significant negative prognostic value (P < .001). This was supported by a Kaplan-Meier survival percentage plot of immunohistochemically p53-undetectable specimens and p53-detectable specimens. These latter patients had a greatly reduced survival time. A relationship was established between p53 immunohistochemical detection and the smoking history of the patients. None of the specimens from the nonsmoking patients expressed immunohistochemically detectable p53 protein. Altered p53 expression was detected in 40.7% of smoking patients. Our findings support the hypothesis of involvement of p53 mutations in tobacco-induced carcinogensis and indicate that altered p53 expression plays an important prognostic role in NSCLC in smokers.

Effect of blood gas derangement on QTc dispersion in severe chronic obstructive pulmonary disease: evidence of an electropathy?

Cardiac arrhythmias are common in patients with respiratory failure from chronic obstructive pulmonary disease (COPD). Several factors may be potentially arrhythmogenic in these patients, including hypoxemia and hypercapnia, acid-base disturbances, cor pulmonale and the use of digitalis, methylxanthines, and sympathomimetic drugs. The aim of this study was to examine the effect of hypoxemia and hypercapnia on QTc dispersion (QTcD) in COPD patients, and to evaluate the effect of a partial correction of one of these pro-arrhythmic factors, the hypoxemia, on Qtc dispersion, as QTcD has been proposed as a marker of heterogeneous repolarization and, hence of ventricular electrical instability. We showed that in 15 hypoxemic/hypercapnic COPD patients, compared to 20 controls, the QTcD was significantly higher (49.7 +/- 10.6 vs. 22.9 +/- 9.8 ms; P = 0.0001); furthermore, after only 24 h of oxygen therapy, and hence after a partial correction of hypoxemia, there was a significant reduction in QTcD in COPD patients (49.7 +/- 10.6 vs. 36.3 +/- 10.1 ms; P = 0.018). The data of the present study suggest that the increase in QTcD may be an early marker of a blood gas mediated electropathy in COPD patients.

CDC2-related kinase PITALRE phosphorylates pRb exclusively on serine and is widely expressed in human tissues

Mammalian cell cycle progression is regulated by sequential activation and inactivation of cyclin‐dependent kinases (cdks). Recently, several new members of the cdk family were cloned, and some of these were shown to complex with different cyclins and to be active at discrete stages of the cell cycle. PITALRE, a new member of this family, was cloned by our laboratory and was shown to be able to phosphorylate pRb protein in vitro. In the current work, we found that PITALRE kinase activity phosphorylated pRb at sites similar to those phosphorylated by the CDC2 kinase, which itself is known to mimic, in vitro, the in vivo phosphorylation of pRb. Phosphorylation of pRb by the PITALRE‐associated kinase activity was on Ser residues exclusively. Moreover, we investigated the expression pattern of PITALRE in normal human tissues, using immunohistochemical techniques so as to gain additional data on the characteristics of this new cdk family member. The protein was widely expressed, although a different tissue distribution and/or level of expression was found in various organs. Some specialized tissues such as blood, lymphoid tissue, ovarian cells, and the endocrine portion of the pancreas showed a high expression level of PITALRE. The specific expression pattern found suggests that PITALRE may be involved in specialized functions in certain cell types. J. Cell. Physiol. 172:265–273, 1997.

Inflammatory effects on human lung epithelial cells after exposure to diesel exhaust micron sub particles (PM1.0) and pollen allergens

Asthma is currently defined as a chronic inflammatory disease of the airway. Several evidence indicate that vehicle emissions in cities is correlated with the allergic respiratory diseases. In the present study, we evaluated in the A549 cells the production and release of IL-4, IL-5 and IL-13 after treatment with sub-micron PM(1.0) particles (PM(1.0)), Parietaria officinalis (ALL), and PM(1.0)xa0+xa0ALL together. Our data demonstrated that PM(1.0)xa0+xa0ALL together exhibited the greatest capacity to induce A549 cells to enhance the expression of IL-4 and IL-5 compared with the only PM(1.0) or ALL treatment. Interestingly, IL-13 that is necessary for allergen-induced airway hyper responsiveness, is increased in cells treated with PM(1.0)xa0+xa0ALL together, but is higher expressed when the cells are treated only with the allergen. Our data support the hypothesis that the urban environment damage the acinar lung units and activates cells of the immune system.

Tumor Suppressors and Cell-Cycle Proteins in Lung Cancer

The cell cycle is the cascade of events that allows a growing cell to duplicate all its components and split into two daughter cells. Cell cycle progression is mediated by the activation of a highly conserved family of protein kinases, the cyclin-dependent kinases (CDKs). CDKs are also regulated by related proteins called cdk inhibitors grouped into two families: the INK4 inhibitors (p16, p15, p19, and p18) and the Cip/Kip inhibitors (p21, p27, and p53). Several studies report the importance of cell-cycle proteins in the pathogenesis and the prognosis of lung cancer. This paper will review the most recent data from the literature about the regulation of cell cycle. Finally, based essentially on the data generated in our laboratory, the expression, the diagnostic, and prognostic significance of cell-cycle molecules in lung cancer will be examined.

Morphology changes in human lung epithelial cells after exposure to diesel exhaust micron sub particles (PM1.0) and pollen allergens

In the recent literature there has been an increased interest in the effects of particulate matter on the respiratory tract. The objective of this study was to use an in vitro model of type II lung epithelium (A549) to evaluate the cell ability to take up sub-micron PM(1.0) particles (PM(1.0)), Parietaria officinalis (ALL), and PM(1.0) + ALL together. Morphological analysis performed by Transmission Electron Microscope (TEM) showed that PM and ALL interacted with the cell surface, then penetrating into the cytoplasm. Each single treatment was able to point out a specific change in the morphology. The cells treated appear healthy and not apoptotic. The main effect was the increase of: multilamellar bodies, lysosomal enzymes, microvilli, and presence of vesicle/vacuoles containing particles. These observations demonstrate morphological and functional alterations related to the PM(1.0) and P. officinalis and confirm the induction of the inflammatory response in lung cells exposed to the inhalable particles.

Evaluation of antitumoral properties of the protease inhibitor indinavir in a murine model of hepatocarcinoma

Purpose: Accumulating evidences show a higher incidence of hepatic neoplasm in HIV/hepatitis C virus (HCV)–coinfected individuals compared with HCV-monoinfected patients. Treatment with HIV-1 protease inhibitors inhibited cancer-promoted angiogenesis in HIV-infected patients affected by Kaposi sarcoma. We aimed to evaluate the antineoplastic potential activities of the protease inhibitor indinavir (Crixivan) in in vitro and in vivo hepatocarcinoma models. Experimental Design: We analyzed effects of indinavir on cell growth and invasiveness in Huh7 and SK-HEP-1 hepatocarcinoma cell lines and on in vivo tumor growth of the same cells in nude mice. Morphologic and molecular analyses on explanted tumors were carried out to evaluate vascularization and apoptosis. Results: We observed a reduced ability to invade an in vitro extracellular matrix for both cell lines treated with indinavir compared with controls (P = 0,001). Moreover, indinavir treatment was able to inhibit matrix metalloproteinase-2 proteolytic activation, whereas there was no effect on cell proliferation. The drug was also able to delay in vivo tumor growth. The inhibition of tumor growth was statistically significant from days 6 to 21 (P = 0.004 and P = 0.003, respectively). Moreover, the drug showed antiangiogenic and proapoptotic actions, as revealed by vessel count and apoptotic index by terminal deoxynucleotide transferase–mediated nick end labeling in explanted tumors. Finally, treatment with indinavir did not block the production of vascular endothelial growth factor in the tumors. Conclusion: Indinavir could be helpful to prevent the development of hepatocarcinomas in HIV/HCV–coinfected individuals. In view of the current trend to substitute protease inhibitors with other antiretroviral agents, this information may have clinical implications.

Molecular Mechanisms of Helicobacter pylori Pathogenesis

Helicobacter pylori infects 50% of mankind. The vast majority of H. pylori infection occurs in the developing countries where up to 80% of the middle‐aged adults may be infected. Bacterial infection causes an inflammatory response that proceeds through a series of intermediated stages of precancerous lesions (gastritis, atrophy, intestinal metaplasia, and dysplasia). Among infected individuals, approximately 10% develops severe gastric lesions such as peptic ulcer disease, 1–3% progresses to gastric cancer (GC) with a low 5‐year survival rate, and 0.1% develops mucosa‐associated lymphoid tissue (MALT). GC is one of the most common cancer and the third leading cause of cancer‐related deaths worldwide. In this review, we have summarized the most recent papers about molecular mechanisms of H. pylori pathogenesis. The main important steps of H. pylori infection such as adhesion, entry in epithelial gastric cells, activation of intracellular pathways until epigenetic modifications have been described. J. Cell. Physiol. 230: 1702–1707, 2015.

Role of cell-cycle regulators in lung cancer

Lung cancer is the leading cause of cancer death worldwide. Histologically, 80% of lung cancers are classified as non‐small‐cell lung cancer (NSCLC), and the remaining 20% as small‐cell lung cancer (SCLC). Lung carcinoma is the result of molecular changes in the cell, resulting in the deregulation of pathways controlling normal cellular growth, differentiation, and apoptosis. This review summarizes some of the most recent findings about the role of cell‐cycle proteins in lung cancer pathogenesis and progression.

Role of NEDD8 in HIV-associated lipodystrophy

The pathogenetic bases of HAART-associated lipodystrophy are still poorly known, even if it is clear that adipose tissue and its metabolism are sensitive to antiretroviral therapy alone and/or in combination with HIV infection. The NEDD8 system is essential for the regulation of protein degradation pathways involved in cell cycle progression, morphogenesis and tumorigenesis. We investigated the possible involvement of NEED8 in adipogenesis and, consequently, in HIV-related lipodystrophy. One hundred HIV-1-infected patients were included in the study. Using an in vitro model of adipogenesis we evaluated the effects on adipogenesis of the forced expression of NEDD8 together with efavirenz, stavudine, saquinavir, amprenavir and indinavir, belonging to the three main classes of anti-HIV medications. We showed that NEDD8 expression level is higher in the peripheral blood of HIV patients developing lipodystrophy. Coherently, forced expression of NEDD8 in an in vitro model of adipogenesis was able to perturb expression of some key proteins involved in adipogenesis, such as C/EBPalpha and PPARgamma, possibly acting throughout the NEDD8/p27/beta-catenin pathway. Moreover, three out of five evaluated drugs were able to affect adipocyte differentiation: efavirenz, stavudine and saquinavir. Finally, we have shown that NEDD8 was expressed in the fat tissue of lipodystrophic patients, being significantly higher in the lipodystrophic patients with respect to the controls, thus further confirming the altered NEDD8 expression in the fat tissue of HIV-infected patients affected by lipodystrophy. Taken together, our data support the hypothesis of an implication of NEDD8 through p27 and beta-catenin pathways in the disruption of adipogenesis and consequent lipodystrophy in patients affected by HIV infection under HAART therapy with qualitative and quantitative differences according to diverse antiretroviral treatments. These evidences indicate the NEDD8/beta-catenin/p27 pathway as a possible molecular target for prevention of lipodystrophy development in patients under HAART therapy.