Epstein-Barr Virus History and Pathogenesis

Epstein-Barr virus (EBV) is the first identified human oncogenic virus that can establish asymptomatic life-long persistence. It is associated with a large spectrum of diseases, including benign diseases, a number of lymphoid malignancies, and epithelial cancers. EBV can also transform quiescent B lymphocytes into lymphoblastoid cell lines (LCLs) in vitro. Although EBV molecular biology and EBV-related diseases have been continuously investigated for nearly 60 years, the mechanism of viral-mediated transformation, as well as the precise role of EBV in promoting these diseases, remain a major challenge yet to be completely explored. This review will highlight the history of EBV and current advances in EBV-associated diseases, focusing on how this virus provides a paradigm for exploiting the many insights identified through interplay between EBV and its host during oncogenesis, and other related non-malignant disorders.

Paired-Box Gene 8 (PAX8) and Its Association With Epithelial Carcinomas

Cancer is the second most common culprit of mortality in the United States and epithelial carcinomas are considered as one of the most predominant types of cancer. The association between epithelial cancers and paired-box gene 8 (PAX8) has been studied significantly before. PAX8 belongs to the paired-box gene family, which plays an important role in the organogenesis of different body organ systems, especially the thyroid gland, the renal system, and the Müllerian system. Immunohistochemical staining is being used to detect PAX8 expression in different epithelial cancers and differentiate them from PAX8-negative tumors. In follicular, papillary, and anaplastic thyroid carcinomas, targeting the PAX8/peroxisome proliferator-activated receptors (PPARs) fusion protein is being considered as a potential mechanism for therapy. Moreover, because of its high expression in primary ovarian cancers, PAX8 is being considered as a target for ovarian cancer treatment as well. More studies are needed to test the possibility of using PAX8 as a possible target for managing endometrial carcinomas. In this article, we review the functions of the PAX8 gene, how its mutations lead to the development of certain epithelial carcinomas, how it can be used as a diagnostic or a prognostic marker, and its potential as a therapeutic target for these cancers.

2-O-Octadecylascorbic acid represses RhoGDIβ expression and ameliorates DNA damage-induced abnormal spindle orientations

The appropriate regulation of spindle orientation maintains proper tissue homeostasis and avoids aberrant tissue repair or regeneration. Spindle misorientation due to imbalance or improper functioning leads to a loss of tissue integrity and aberrant growth, such as tissue loss or overgrowth. Pharmacological manipulation to prevent spindle misorientation will enable a better understanding of how spindle orientation is involved in physiological and pathological conditions and will provide therapeutic possibilities to treat patients associated with abnormal tissue function caused by spindle misorientation. N-terminal-deleted Rho guanine nucleotide dissociation inhibitor β (RhoGDIβ/RhoGDI2/LyGDI) produced by caspase-3 activation perturbs spindle orientation in surviving cells following exposure to either ionizing radiation or UVC. Thus, presumably, RhoGDIβ cleaved by caspase-3 activation acts as a determinant of radiation-induced spindle misorientation that promote aberrant tissue repair due to deregulation of directional organization of cell population and therefore becomes a potential target of drugs to prevent such response. The objective of this study was to screen and identify chemicals that suppress RhoGDIβ expression. We focused our attention on ascorbic acid (AA) derivatives because of their impact on the maintenance of skin tissue homeostasis. Here, we screened for AA derivatives that suppress RhoGDIβ expression in HeLa cells and identified a lipophilic derivative, 2-O-octadecylascorbic acid (2-OctadecylAA), as a novel RhoGDIβ inhibitor that ameliorated ionizing radiation-induced abnormal spindle orientations. Among all examined AA derivatives, which were also antioxidative, the inhibition activity was specific to 2-OctadecylAA. Therefore, this activity was not due to simple antioxidant properties. 2-OctadecylAA was previously shown to prevent hepatocellular carcinoma development. Our findings suggest that the anticarcinogenic effects of 2-OctadecylAA are partly due to RhoGDIβ inhibition mechanisms by which spindle orientation perturbations are attenuated. Thus, the molecular targeting features of RhoGDIβ warrant its further development for the treatment or control of spindle orientation abnormalities that affect epithelial homeostasis.

The efficacy and potential predictive factors of PD-1/PD-L1 blockades in epithelial carcinoma patients: a systematic review and meta analysis

Background

This systematic analysis aims to assess the efficacy of PD-1/PD-L1 blockades compared with non-PD-1/PD-L1 therapy and investigate the potential predictive factors in epithelial carcinoma patients.

Results

A total of 11 trials with 6716 patients of melanoma, non-small cell lung cancer (NSCLC) and renal cell carcinoma (RCC) were included. The pooled HRs (95%CI) were 0.67 (0.62, 0.73), p < 0.001 for OS and 0.66 (0.57, 0.76), p < 0.001 for PFS. In subgroup analyses, HRs were 0.58 (0.50, 0.66), p < 0.001 in PD-L1 ≥ 1% group, 0.75 (0.63, 0.89), p = 0.001 in PD-L1 < 1% group for OS and 0.59 (0.48, 0.72), p < 0.001 in PD-L1 ≥ 1% group, 0.80 (0.59, 1.07), p = 0.136 in PD-L1 < 1% group for PFS. The p values of pooled HRs for OS in different age, sex and ECOG score groups were less than 0.001. In NSCLC patients, aggregated HRs for OS were 1.40 (0.92, 2.12), p = 0.114 in EGFR mutant group and 0.88 (0.59, 1.32), p = 0.536 in never smokers.

Methods

A systematic search from January 2010 to April 2016 was conducted for eligible clinical trials. Based on the data of hazard ratios (HRs) and 95% confidence intervals (CIs) for overall survival (OS) and progression-free survival (PFS), we assessed the pooled HRs and proposed the subgroup analyses.

Conclusions

PD-1/PD-L1 blockades prolonged OS and PFS in epithelial carcinoma patients. PD-L1 expression was a predictive factor for PFS but not predictive for OS. Age, sex and ECOG score were excluded to predict any of the efficacy endpoints. Smoking history and EGFR wild type were associated with extended OS in NSCLC patients.

Selective lysis of breast carcinomas by simultaneous stimulation of sodium channels and blockade of sodium pumps

Sodium influx through voltage-gated sodium channels (VGSCs) coupled with balanced removal of sodium ions via Na⁺, K⁺-ATPase is a major determinant of cellular homeostasis and intracellular ionic concentration. Interestingly, many metastatic carcinomas express high levels of these channels. We hypothesized that if excess VGSCs are activated and Na⁺, K⁺-ATPase is simultaneously blocked, the intracellular Na⁺ concentration should increase, resulting in water movement into the cell, causing swelling and lytic cell death. MDA-MB-231 breast cancer cells over-express VGSCs by 7-fold. To test our hypothesis, we treated these cells in vitro with the Na⁺, K⁺-ATPase blocker, ouabain, and then stimulated with a sublethal electric current. For in vivo histologic and survival studies, MDA-MB-231 xenografts were established in Nu/J mice. Mice injected with saline or ouabain were electrically stimulated with trains of 10 msec 10V DC pulses. Within seconds to minutes, the cells swelled and lysed. MCF-10a cells, which express normal VGSCs levels, were unaffected by this treatment. Cells from the weakly-malignant cell line, MCF-7, which express 3-fold greater VGSCs than MCF-10a cells, displayed an intermediate time-to-lysis. The rate of lysis correlated directly with the degree of sodium channel expression and malignancy. We also demonstrated efficacy in cell lines from prostate, colon and lung carcinomas. Treated MDA-MB-231 xenografts showed 60-80% cell death. In survival studies, TOL-treated mice showed significantly slower tumor growth vs. controls. These results are evidence that this "targeted osmotic lysis" represents a novel method for selectively killing cancer cells and warrants further investigation as a potential treatment for advanced and end-stage breast cancer.

Molecular basis of arsenite (As⁺³)-induced acute cytotoxicity in human cervical epithelial carcinoma cells

BACKGROUND

Rapid industrialization is discharging toxic heavy metals into the environment, disturbing human health in many ways and causing various neurologic, cardiovascular, and dermatologic abnormalities and certain types of cancer. The presence of arsenic in drinking water from different urban and rural areas of the major cities of Pakistan, for example, Lahore, Faisalabad, and Kasur, was found to be beyond the permissible limit of 10 parts per billion set by the World Health Organization. Therefore the present study was initiated to examine the effects of arsenite (As(+3)) on DNA biosynthesis and cell death.

METHODS

After performing cytotoxic assays on a human epithelial carcinoma cell line, expression analysis was done by quantitative polymerase chain reaction, western blotting, and flow cytometry.

RESULTS

We show that As(+3) ions have a dose- and time-dependent cytotoxic effect through the activation of the caspase-dependent apoptotic pathway. In contrast to previous research, the present study was designed to explore the early cytotoxic effects produced in human cells during exposure to heavy dosage of As(+3) (7.5 µg/ml). Even treatment for 1 h significantly increased the mRNA levels of p21 and p27 and caspases 3, 7, and 9. It was interesting that there was no change in the expression levels of p53, which plays an important role in G2/M phase cell cycle arrest.

CONCLUSION

Our results indicate that sudden exposure of cells to arsenite (As(+3)) resulted in cytotoxicity and mitochondrial-mediated apoptosis resulting from up-regulation of caspases.

[Rare association of a pleomorphic adenoma and epithelial myoepithelial carcinoma of the parotid gland]

Le Carcinome épithélial - myoépithélial (CEM) est une tumeur maligne rare des glandes salivaires touchant principalement la glande parotide. Son association avec un adénome pléomorphe est exceptionnelle. Nous rapportons le cas d'une femme de 57 ans avec adénome pléomorphe de la glande parotide évoluant depuis plusieurs années. L'augmentation récente du volume de la glande associée à l'apparition d'adénopathies cervicales homolatérales nous a fait penser à une transformation maligne. L'examen histologique final après parotidectomie totale a montré une association inattendue d'un adénome pléomorphe et un CEM. Le CEM est une tumeur maligne de bas grade. Elle peut survenir de novo ou sur un adénome pléomorphe. La transformation maligne de l'adénome est suspectée devant l'augmentation rapide du volume de l'adénome avec apparition d'adénopathies cervicales. Toutefois, ces modifications cliniques peuvent annoncer l'apparition d'une tumeur distincte. Malgré sa tendance à la récidive locale et un faible potentiel métastatique, de rares cas de CEM peuvent avoir un comportement agressif et des métastases à distance. Le traitement consiste principalement en une résection chirurgicale complète si possible suivie d'une radiothérapie dans le but de prévenir la récidive locale.

Early diagnosis of oral cancer based on the surface plasmon resonance of gold nanoparticles

The high mortality rate in cancer such as oral squamous cell carcinoma is commonly attributed to the difficulties in detecting the disease at an early treatable stage. In this study, we exploited the ability of gold nanoparticles to undergo coupled surface plasmon resonance and set up strong electric fields when closely-spaced to improve the molecular contrast signal in reflectance-based imaging and also to enhance the Raman signal of bioanalytes in cancer. Colloidal gold nanoparticles were synthesized and conjugated to anti-epidermal growth factor receptor (EGFR) for imaging. A self-assembled surface enhanced Raman scattering (SERS)-active gold nanoparticle monolayer film was also developed as a biosensing surface using a simple drop-dry approach. We have shown that gold nanoparticles could elicit an optical contrast to discriminate between cancerous and normal cells and their conjugation with antibodies allowed them to map the expression of relevant biomarkers for molecular imaging under confocal reflectance microscopy. We have also shown that the SERS spectra of saliva from the closely-packed gold nanoparticles films was differentiable between those acquired from normal individuals and oral cancer patients, thus showing promise of a simple SERS-based saliva assay for early diagnosis of oral cancer.