Correlation of p53 gene mutation and expression of P53 protein in cholangiocarcinoma

The Assessment of Diet Contaminated with Aflatoxin B1 in Juvenile Turbot (Scophthalmus maximus) and the Evaluation of the Efficacy of Mitigation of a Yeast Cell Wall Extract

This study aimed to investigate the effects of dietary AFB₁ on growth performance, health, intestinal microbiota communities and AFB₁ tissue residues of turbot and evaluate the mitigation efficacy of yeast cell wall extract, Mycosorb^® (YCWE) toward AFB₁ contaminated dietary treatments. Nine experimental diets were formulated: Diet 1 (control): AFB₁ free; Diets 2-5 or Diets 6-9: 20 μg AFB₁/kg diet or 500 μg AFB₁/kg diet + 0%, 0.1%, 0.2%, or 0.4% YCWE, respectively). The results showed that Diet 6 significantly decreased the concentrations of TP, GLB, C3, C4, T-CHO, TG but increased the activities of AST, ALT in serum, decreased the expressions of CAT, SOD, GPx, CYP1A but increased the expressions of CYP3A, GST-ζ₁, p53 in liver. Diet 6 increased the AFB₁ residues in serum and muscle, altered the intestinal microbiota composition, decreased the bacterial community diversity and the abundance of some potential probiotics. However, Diet 8 and Diet 9 restored the immune response, relieved adverse effects in liver, lowered the AFB₁ residues in turbot tissues, promoted intestinal microbiota diversity and lowered the abundance of potentially pathogens. In conclusion, YCWE supplementation decreased the health effects of AFB₁ on turbot, restoring biomarkers closer to the mycotoxin-free control diet.

Common features between neoplastic and preneoplastic lesions of the biliary tract and the pancreas

the bile duct system and pancreas show many similarities due to their anatomical proximity and common embryological origin. Consequently, preneoplastic and neoplastic lesions of the bile duct and pancreas share analogies in terms of molecular, histological and pathophysiological features. Intraepithelial neoplasms are reported in biliary tract, as biliary intraepithelial neoplasm (BilIN), and in pancreas, as pancreatic intraepithelial neoplasm (PanIN). Both can evolve to invasive carcinomas, respectively cholangiocarcinoma (CCA) and pancreatic ductal adenocarcinoma (PDAC). Intraductal papillary neoplasms arise in biliary tract and pancreas. Intraductal papillary neoplasm of the biliary tract (IPNB) share common histologic and phenotypic features such as pancreatobiliary, gastric, intestinal and oncocytic types, and biological behavior with the pancreatic counterpart, the intraductal papillary mucinous neoplasm of the pancreas (IPMN). All these neoplastic lesions exhibit similar immunohistochemical phenotypes, suggesting a common carcinogenic process. Indeed, CCA and PDAC display similar clinic-pathological features as growth pattern, poor response to conventional chemotherapy and radiotherapy and, as a consequence, an unfavorable prognosis. The objective of this review is to discuss similarities and differences between the neoplastic lesions of the pancreas and biliary tract with potential implications on a common origin from similar stem/progenitor cells.

Marine Carotenoid Fucoxanthin Possesses Anti-Metastasis Activity: Molecular Evidence

Fucoxanthin is commonly found in marine organisms; however, to date, it has been one of the scarcely explored natural compounds. We investigated its activities in human cancer cell culture-based viability, migration, and molecular assays, and found that it possesses strong anticancer and anti-metastatic activities that work irrespective of the p53 status of cancer cells. In our experiments, fucoxanthin caused the transcriptional suppression of mortalin. Cell phenotype-driven molecular analyses on control and treated cells demonstrated that fucoxanthin caused a decrease in hallmark proteins associated with cell proliferation, survival, and the metastatic spread of cancer cells at doses that were relatively safe to the normal cells. The data suggested that the cancer therapy regimen may benefit from the recruitment of fucoxanthin; hence, it warrants further attention for basic mechanistic studies as well as drug development.

Aberrant mRNA splicing generates oncogenic RNA isoforms and contributes to the development and progression of cholangiocarcinoma

Cholangiocarcinoma is a lethal biliary cancer, with an unclear molecular pathogenesis. Alternative splicing is a post-transcriptional modification that generates mature mRNAs, which are subsequently translated into proteins. Aberrant alternative splicing has been reported to serve a role in tumor initiation, maintenance and metastasis in several types of human cancer, including cholangiocarcinoma. In this review, the aberrant splicing of genes and the functional contributions of the spliced genes, in the carcinogenesis, progression and aggressiveness of cholangiocarcinoma are summarized. In addition, factors that influence this aberrant splicing that may be relevant as therapeutic targets or prognosis markers for cholangiocarcinoma are discussed.

No Evaluation of Serum P53 Levels in Iraqi Female Breast Cancer Patients

Breast cancer is the most common cancer diagnosed and the second leading cause of cancer death among Iraqi women. The population was exposed to high levels of depleted uranium following the first and second Gulf Wars and this might be a risk factor. Protein 53 (p53) or Tumor protein 53 (Tp53) was originally defined as an oncogenic protein. The aim of the study was to evaluate P-53 serum concentrations in fifty Iraqi female breast cancer patients and twenty five healthy volunteers using the ELISA technique. All these patients attended the Teaching Hospital of AL Diwaniyah during the period between June 2016 to March 2017. The mean values for TP53 concentration in patients with breast cancer and apparently healthy groups were 47+33.5 U/ml and 27. 8+12.7 U/ml, respectively. The results showed no significantly difference , in contrast to most studies conducted elsewhere in the world.

Cholangiocarcinoma: Present Status and Molecular Aspects of Diagnosis

Cholangiocarcinomas are neoplasms that involve the epithelial cells of the bile duct, also known as cholangiocytes. This disease is difficult to diagnose early, as most symptoms present late in the disease. In addition, the specific anatomic position can cause periductal extension and result in a very low radical excision rate and a very poor prognosis. Improved understanding of the features underlying the onset of cholangiocarcinoma and its carcinogenic mechanism may lead to early diagnosis and better prognosis. With the development of molecular biology, much has been learned about oncogenes, tumor-suppressor genes, DNA methylation, microRNAs, and the molecular mechanisms of tumor invasion and metastasis. Based on our research and others, this review article will discuss the current status and prospects of early diagnosis of cholangiocarcinoma.

Implications for chronic toxicity of benzo[a]pyrene in sea bream cultured hepatocytes: Cytotoxicity, inflammation, and cancerogenesis

Benzo[a]pyrene (B[a]P) is the most studied dangerous polycyclic aromatic hydrocarbon for its hepatotoxic, carcinogenic, mutagenic, teratogenic, and immunosuppressant effects, which can affect both wild and farmed marine fish through the trophic chain. This study investigated, for the first time, the chronic effects induced in vitro by B[a]P prolonged exposure on gilthead sea bream (Sparus aurata L.) hepatocytes, evaluating the cellular and nuclear latent damage. The purpose was to characterize the kind of B[a]P cyto- and genotoxic damage by morphological and immunocytochemical parameters applied in combination with the use of multiple assay endpoints. In light of our results, the short-term effects at higher B[a]P doses were linked to higher cytotoxicities and necrotic lysis, whereas a sustained inflammatory response at medium-low doses was perceived as a mitochondria-mediated apoptosis, both by surface and nuclear morphological changes. The strong immunoreactivity for the cleaved caspase-3 showed that the labeled cells committed suicide by apoptosis. B[a]P involvement on carcinogenesis comes from prolonged exposure at lower doses, establishing the connection between the escape from apoptosis and the selection of a tumoral phenotype. Cells colabeled with proliferating cell nuclear antigen/caspase-3 within the proliferative foci, were proliferating transformed oval stem cells, which escaped the suicide by apoptosis allowing cancer development. Finally, it was established that sea bream cultured hepatocytes are highly sensitive to chronic B[a]P exposure, as serious genotoxic effects were found even at the lowest doses.

Molecular Targets in Biliary Carcinogenesis and Implications for Therapy

Biliary tract cancers (BTCs) encompass a group of invasive carcinomas, including cholangiocarcinoma (intrahepatic, perihilar, or extrahepatic), and gallbladder carcinoma. Approximately 90% of patients present with advanced, unresectable disease and have a poor prognosis. The latest recommendation is to treat advanced or metastatic disease with gemcitabine and cisplatin, although chemotherapy has recorded modest survival benefits. Comprehension of the molecular basis of biliary carcinogenesis has resulted in experimental trials of targeted therapies in BTCs, with promising results. This review addresses the emerging role of targeted therapy in the treatment of BTCs. Findings from preclinical studies were reviewed and correlated with the outcomes of clinical trials that were undertaken to translate the laboratory discoveries.

IMPLICATIONS FOR PRACTICE

Biliary tract cancers are rare. Approximately 90% of patients present with advanced, unresectable disease and have a poor prognosis. Median overall and progression-free survival are 12 and 8 months, respectively. Because chemotherapy has recorded modest survival benefits, targeted therapies are being explored for personalized treatment of these cancers. A comprehensive review of targeted therapies in biliary tract cancers was undertaken to present emerging evidence from laboratory and/or molecular studies as they translate to clinical trials and outcomes. The latest evidence on this topic is presented to clinicians and practitioners to guide decisions on treatment of this disease.

Serum p53 Antibody Is Not Associated with p53 Immunoreactivity in Patients with Pancreatobiliary Cancers

Background. Recent diagnostic imaging tests contribute to improving the diagnosis of pancreatobiliary cancers. However, it is not practical to perform these tests for all patients as screening. Thus, less-invasive and simple screening tests are still required. A method to detect the IgG antibody induced in serum against the p53 protein accumulating due to p53 gene mutation, as a biomarker, was developed around 1990. Method. 35 patients with pancreatic cancer, 12 patients with biliary tract cancer, and 31 patients with benign pancreatobiliary diseases were entered into this study. Measurement of serum anti-p53 antibody was conducted in all patients. In addition, the rate of p53 protein overexpression was examined in those cases that could be examined pathologically. Result. Among all patients in the pancreatic cancer and biliary tract cancer groups, there was no patient with serum anti-p53 antibody positive value that exceeded the standard value. The rate of p53 protein overexpression was 48.0% in the patients with pancreatobiliary cancers and 0% in the benign pancreatobiliary diseases group. Conclusion. Serum anti-p53 antibody measurement does not contribute to the diagnosis of pancreatobiliary cancers. Instead, traditional p53 immunostaining still appears to be valuable in combination with standard procedures.

Switching p53 states by calcium: dynamics and interaction of stress systems

The integration of calcium and a p53-Mdm2 oscillator model is studied using a deterministic as well as a stochastic approach, to investigate the impact of a calcium wave on single cell dynamics and on the inter-oscillator interaction. The high dose of calcium in the system activates the nitric oxide synthase, synthesizing nitric oxide which then downregulates Mdm2 and influences drastically the p53-Mdm2 network regulation, lifting the system from a normal to a stressed state. The increase in calcium level switches the system to different states, as identified by the different behaviours of the p53 temporal dynamics, i.e. oscillation death to sustain the oscillation state via a mixed state of dampened and oscillation death states. Further increase of the calcium dose in the system switches the system from sustained to oscillation death state again, while an excess of calcium shifts the cell to an apoptotic state. Another important property of the calcium ion is its ability to behave as a synchronizing agent among the interacting systems. The time evolution of the p53 dynamics of the two diffusively coupled systems at stress condition via Ca(2+) shows synchronization between the two systems. The noise contained in the system interestingly helps the system to maintain its stabilized state (normal condition). However, noise has the tendency to destruct the synchronization effect, which means that it tries to restrict the system from external signals to maintain its normal condition. However, at the stress condition, the synchronization rate is found to be faster.

Targeted drug regulation on methylation of p53-BAX mitochondrial apoptosis pathway affects the growth of cholangiocarcinoma cells

OBJECTIVE

To study the mechanism of 5-aza-2-deoxycytidine (DAC; a methylation inhibitor) on growth of the human cholangiocarcinoma QBC939 cell line.

METHODS

A colourimetric assay was used to detect growth of QBC939 cells treated with DAC (0.1-100 μmol/l) over 24 h, 48 h and 72 h. Cell morphology was observed by transmission electron microscopy (TEM). The cell cycle and apoptosis were analysed by flow cytometry. Hypermethylation of the promoters of the p53-BAX mitochondrial apoptosis genes cyclin-dependent kinase inhibitor 2A (CDKN2A), death-associated protein kinase 1 (DAPK1) and PYD and CARD domain containing (PYCARD) was detected by methylation-specific polymerase chain reaction, with and without DAC treatment.

RESULTS

DAC inhibited QBC939 cell growth with a half maximal inhibitory concentration of 5 μmol/l at 72 h. After DAC treatment, apoptosis was observed by TEM. Flow cytometric analysis of propidium iodide-positive cells demonstrated increased apoptosis of DAC-treated QBC939 cells (43.04%) compared with untreated cells (4.31%). DAC treatment resulted in demethylation of the gene promoters of CDKN2A and DAPK1 in QBC939 cells.

CONCLUSIONS

DAC induces apoptosis of QBC939 cells by reactivation of hypermethylated p53-BAX mitchondrial apoptosis genes in cholangiocarcinoma cells.

Correlation between promoter methylation of p14(ARF), TMS1/ASC, and DAPK, and p53 mutation with prognosis in cholangiocarcinoma

Background

To study the methylation status of genes that play a role in the p53-Bax mitochondrial apoptosis pathway and its clinical significance in cholangiocarcinoma.

Patients and Methods

Out of 36 cases cholangiocarcinoma patients from April 2000 to May 2005 were collected.Promoter hypermethylation of DAPK, p14^ARF, and ASC were detected by methylation-specific PCR on cholangiocarcinoma and normal adjacent tissues samples. Mutation of the p53 gene was examined by automated sequencing. Correlation between methylation of these genes and/or p53 mutation status with clinical characteristics of patients was investigated by statistical analysis.

Results

We found 66.7% of 36 cholangiocarcinoma patients had methylation of at least one of the tumor suppressor genes analyzed. p53 gene mutation was found in 22 of 36 patients (61.1%). Combined p53 mutation and DAPK, p14^ARF, and/or ASC methylation was detected in 14 cases (38.9%). There were statistically significant differences in the extent of pathologic biology, differentiation, and invasion between patients with combined p53 mutation and DAPK, p14^ARF, and/or ASC methylation compared to those without (P < 0.05). The survival rate of patients with combined DAPK, p14^ARF, and ASC methylation and p53 mutation was poorer than other patients (P < 0.05).

Conclusion

Our study indicates that methylation of DAPK, p14^ARF, and ASC in cholangiocarcinoma is a common event. Furthermore, p53 mutation combined with DAPK, p14^ARF, and/or ASC methylation correlates with malignancy and poor prognosis.

CpG-island methylation study of liver fluke-related cholangiocarcinoma

BACKGROUND

Genetic changes have been widely reported in association with cholangiocarcinoma (CCA), while epigenetic changes are poorly characterised. We aimed to further evaluate CpG-island hypermethylation in CCA at candidate loci, which may have potential as diagnostic or prognostic biomarkers.

METHODS

We analysed methylation of 26 CpG-islands in 102 liver fluke related-CCA and 29 adjacent normal samples using methylation-specific PCR (MSP). Methylation of interest loci was confirmed using pyrosequencing and/or combined bisulfite restriction analysis, and protein expression by immunohistochemistry.

RESULTS

A number of CpG-islands (OPCML, SFRP1, HIC1, PTEN and DcR1) showed frequency of hypermethylation in >28% of CCA, but not adjacent normal tissues. The results showed that 91% of CCA were methylated in at least one CpG-island. The OPCML was the most frequently methylated locus (72.5%) and was more frequently methylated in less differentiated CCA. Patients with methylated DcR1 had significantly longer overall survival (Median; 41.7 vs 21.7 weeks, P=0.027). Low-protein expression was found in >70% of CCA with methylation of OPCML or DcR1.

CONCLUSION

Aberrant hypermethylation of certain loci is a common event in liver fluke-related CCA and may potentially contribute to cholangiocarcinogenesis. The OPCML and DcR1 might serve as methylation biomarkers in CCA that can be readily examined by MSP.

Prognostic molecular markers in cholangiocarcinoma: a systematic review

The worldwide incidence of cholangiocarcinoma (CC) is steadily rising, with the incidence in United Kingdom (UK) now exceeding 1000 cases per year. It is an aggressive malignancy typified by unresponsiveness to the existing chemotherapy and radiotherapy regimes in the vast majority of cases. Surgery offers the only hope of a cure, though post-operative disease recurrence is common, with 5-year survival rates of less than 25% following resection. Developments in molecular techniques and improved understanding of the basis of carcinogenesis in CC has led to examination of the role of biomarkers in predicting poor outcome. This systematic review examines published evidence relating to the prognostic significance of these molecular markers in CC. Of the molecular markers which have been investigated to date, p53 mutation, cyclins, proliferation indices, mucins, CA19-9, CRP and aneuploidy appear to hold significant potential as predictors of outcome in CC. These and other biomarkers may themselves represent novel therapeutic targets for CC.