The rapid scientific interest in gut microbiota (GM) has coincided with a global increase in the prevalence of infectious and non-infectivous liver diseases. GM, which is also called “the new virtual metabolic organ”, makes axis with a number of extraintestinal organs, such as kidneys, brain, cardiovascular, and the bone system. The gut-liver axis has attracted greater attention in recent years. GM communication is bi-directional and involves endocrine and immunological mechanisms. In this way, gut-dysbiosis and composition of “ancient” microbiota could be linked to pathogenesis of numerous chronic liver diseases such as chronic hepatitis B (CHB), chronic hepatitis C (CHC), alcoholic liver disease (ALD), non-alcoholic fatty liver disease (NAFLD), non-alcoholic steatohepatitis (NASH), development of liver cirrhosis, and hepatocellular carcinoma (HCC). In this paper, we discuss the current evidence supporting a GM role in the management of different chronic liver diseases and potential new therapeutic GM targets, like fecal transplantation, antibiotics, probiotics, prebiotics, and symbiotics. We conclude that population-level shifts in GM could play a regulatory role in the gut-liver axis and, consequently, etiopathogenesis of chronic liver diseases. This could have a positive impact on future therapeutic strategies.

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Although profoundly studied, etiology of pancreatic cancer (PC) is still rather scant. Exposure to cadmium (Cd), a ubiquitous metal associated with well-established toxic and carcinogenic properties, has been hypothesized to one putative cause of PC. Hence, we analyzed recently published observational studies, meta-analyses, and experimental animal and in vitro studies with the aim of summarizing the evidence of Cd involvement in PC development and describing the possible mechanisms. Consolidation of epidemiological data on PC and exposure to Cd indicated a significant association with an elevated risk of PC among general population exposed to Cd. Cadmium exposure of laboratory animals was showed to cause PC supporting the findings suggested by human studies. The concordance with human and animal studies is buttressed by in vitro studies, although in vitro data interpretation is problematic. In most instances, only significant effects are reported, and the concentrations of Cd are excessive, which would skew interpretation. Previous reports suggest that oxidative stress, apoptotic changes, and DNA cross-linking and hypermethylation are involved in Cd-mediated carcinogenesis. Undoubtedly, a significant amount of work is still needed to achieve a better understanding of the Cd involvement in pancreatic cancer which could facilitate prevention, diagnosis, and therapy of this fatal disease.

Pancreatic cancer (PC) is insidious with a high mortality rate due to the lack of symptomology prior to diagnosis. Mitochondrial involvement in PC development is becoming accepted, and exposure to cadmium (Cd) is suspected of being a risk factor for the development of PC; however, the mechanisms involved remain unclear. In this study, we examined the role of Cd as a mitochondrial toxicant and whether alterations in mitochondrial function may be an underlying cause for the development of PC. In this study, cadmium chloride (CdCl 2 )-mediated toxicity in hTERT-HPNE and AsPC-1 pancreatic cell lines was determined by MTT assay. We also investigated the release of LDH and the generation of free radicals. Mitochondrial toxicity assays were performed in media containing glucose (25 mM) or galactose (10 mM) and following exposure to CdCl 2 (0-100 μ M) followed by MTT assay. For the confirmation of mitochondrial toxicity, we measured the release of ATP following exposure to CdCl 2 . Initial experiments confirmed that exposure to CdCl 2 did not reduce the viability of either cell line until a concentration of >10 μ M was used. Non-linear analysis of the response curves revealed lethal concentration 50% (LC 50 ) values for CdCl 2 in the HPNE cells of 77 μ M compared to 42 μ M in the AsPC-1 cells (P<0.01). The CdCl 2 -mediated mitochondrial toxic effects were greater in the HPNE cells, suggesting a heightened sensitivity to the effects of CdCl 2 , not due to elevated oxidative stress. Increased mitochondrial toxic sensitivity was indicated by a 73.4% reduction in IC 50 values in the HPNE cells cultured in galactose compared to culture in glucose media, whereas the AsPC-1 cells exhibited a 58.8% reduction in IC 50 values. In addition, the higher concentration of CdCl 2 elicited a significant cell-dependent effect on ATP release in both cell lines, suggestive of CdCl 2 being a mitochondrial toxicant. Cell survival was unaffected following exposure to low concentrations of CdCl 2 ; however, exposure did alter mitochondrial function (control cells > tumor cells). Therefore, the findings of this study indicate that the mitochondria may be a site of action for cadmium in promoting tumor development.

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Patients with acute promyelocytic leukemia (APL) show other chromosome aberrations in addition to t(15;17) but their influence on the clinical outcome is still unclear. We have cytogeneticaly analyzed 43 APL patients with t(15;17)(q22;q21), treated with all-trans-retinoic acid (ATRA) according to the recommendations of the European APL 91 Group. Additional chromosome aberrations were observed in 14/43 patients (33%) studied at initial diagnosis. These patients were designed as 'complex' karyotype group and were compared to patients with t(15;17) asa sole cytogenetic abnormality ('simple' karyotype group). The 'complex' group had significantly lower platelet count and fibrinogen level and fewer cases without significant DIC at diagnosis than the 'simple' group. Comparison of 'simple' and 'complex' groups showed significant difference in complete remission rate (76% vs 35.7%, P = 0.0148) and early death rate (24% vs 64.3%, P = 0.0141). Survival analysis showed that the presence of additional chromosome abnormalities and significant DIC had an adverse effects on prognosis (P = 0.036 and P = 0.041, respectively), independent on other prognostic factors. These data indicate more aggressive biological nature of leukemic cells in patients with additional chromosome aberrations. Supplementary therapeutic strategies may be required for this subgroup of APL patients.

Pancreatic ductal adenocarcinoma (PDAC) is the most aggressive and invasive type of pancreatic cancer (PCa) and is expected to be the second most common cause of cancer-associated deaths. The high mortality rate is due to the asymptomatic progression of the clinical features until the advanced stages of the disease and the limited effectiveness of the current therapeutics. Aberrant expression of several microRNAs (miRs/miRNAs) has been related to PDAC progression and thus they could be potential early diagnostic, prognostic, and/or therapeutic predictors for PDAC. miRs are small (18 to 24 nucleotides long) non-coding RNAs, which regulate the expression of key genes by targeting their 3′-untranslated mRNA region. Increased evidence has also suggested that the chemoresistance of PDAC cells is associated with metabolic alterations. Metabolic stress and the dysfunctionality of systems to compensate for the altered metabolic status of PDAC cells is the foundation for cellular damage. Current data have implicated multiple systems as hallmarks of PDAC development, such as glutamine redox imbalance, oxidative stress, and mitochondrial dysfunction. Hence, both the aberrant expression of miRs and dysregulation in metabolism can have unfavorable effects in several biological processes, such as apoptosis, cell proliferation, growth, survival, stress response, angiogenesis, chemoresistance, invasion, and migration. Therefore, due to these dismal statistics, it is crucial to develop beneficial therapeutic strategies based on an improved understanding of the biology of both miRs and metabolic mediators. This review focuses on miR-mediated pathways and therapeutic resistance mechanisms in PDAC and evaluates the impact of metabolic alterations in the progression of PDAC.

Despite the existing controversy concerning pathophysiological mechanism, the clinical presentation and treatment modalities of patients with MAL syndrome, it is evident that careful selection and adequate surgical treatment may significantly reduce symptoms in these patients.