No abstract

Since December 2019, a new form of severe acute respiratory syndrome (SARS) from a novel strain of coronavirus (SARS coronavirus 2 [SARS‐CoV‐2]) has been spreading worldwide. The disease caused by SARS‐CoV‐2 was named Covid‐19 and declared as a pandemic by the World Health Organization in March 2020. Clinical symptoms of Covid‐19 range from common cold to more severe disease defined as pneumonia, hypoxia, and severe respiratory distress. In the next stage, disease can become more critical with respiratory failure, sepsis, septic shock, and/or multiorgan failure. Outcomes of Covid‐19 indicate large gaps between the male–female and the young–elder groups. Several theories have been proposed to explain variations, such as gender, age, comorbidity, and genetic factors. It is likely that mixture of genetic and nongenetic factors interplays between virus and host genetics and determines the severity of disease outcome. In this review, we aimed to summarize current literature in terms of potential host genetic and epigenetic factors that associated with increased severity of Covid‐19. Several studies indicated that the genetic variants of the SARS‐CoV‐2 entry mechanism‐related (angiotensin‐converting enzymes, transmembrane serine protease‐2, furin) and host innate immune response‐related genes (interferons [IFNs], interleukins, toll‐like receptors), and human leukocyte antigen, ABO, 3p21.31, and 9q34.2 loci are critical host determinants related to Covid‐19 severity. Epigenetic mechanisms also affect Covid‐19 outcomes by regulating IFN signaling, angiotensin‐converting enzyme‐2, and immunity‐related genes that particularly escape from X chromosome inactivation. Enhanced understanding of host genetic and epigenetic factors and viral interactions of SARS‐CoV‐2 is critical for improved prognostic tools and innovative therapeutics.

The PTEN tumor suppressor is the second most commonly inactivated gene across cancer types. While it's role in PI3K/AKT and DNA damage pathways are clear, increasing evidences suggest that PTEN may also promote anti-tumor immunity. PTEN-deficient tumors are characterized by (i) reduced levels of cytotoxic T cells, helper T cells and NK cells, (ii) elevated pro-oncogenic inflammatory cytokines like CCL2 and (iii) increased levels of immunosuppressive cells such as MDSCs and Tregs. An intriguing possibility is that link between PTEN and anti-tumor immunity is mediated by the interferon signaling pathway. In this review, we summarize the evidences for the mechanistic link between PTEN deficiency and immunosuppressive tumor microenvironment and the interferon signaling pathway. We further discuss how the link between these pathways can be exploited for development of personalized immunotherapy for patients with PTEN deficient tumors.

Although some new-generation CAD/CAM and provisional restoration materials display slight cytotoxicity values, the results are still within the reliable range, and they can safely be used in clinical conditions.

A new platform for drug, gene and peptide-protein delivery is emerging, under the common name of “extracellular vesicles”. Extracellular vesicles (EVs) are 30-1000 nm-sized cell-derived, liposome-like vesicles. Current research on EVs as nano-delivery systems for small-molecule drugs and genetic material, reveal that these tiny, biologically-derived vesicles carry a great potential to boost the efficacy of many therapeutic protocols. Several features of EVs; from efficacy to safety, from passive to active targeting ability, the opportunity to be biologically or chemically labelled, and most importantly, their eobiotic origin make them promising candidate for development of the next generation personalized nanomedicines. The aim of this article is to provide a view on the current research in which EVs are used as drug/genetic material delivery systems. Their application areas, drug loading and targeting strategies, and biodistribution properties are discussed.This article is open to POST-PUBLICATION REVIEW. Registered readers (see “For Readers”) may comment by clicking on ABSTRACT on the issue’s contents page.

We have investigated defective steps in apoptosis that might account for the development of resistance. For this purpose, A549 and Calu1 NSCLC (non-small-cell lung cancer) cell lines were treated with cisplatin to obtain resistant sub-lines. Gene expression profiles and the phosphorylation status of the BAD (Bcl-2/Bcl-XL-antagonist, causing cell death) protein were determined for each cell line. Cell death and cytochrome c release were analysed after treating cell lines with their appropriate cisplatin doses. Gene expression of BAD, Bid, caspases 4 and 6 were clearly decreased in the resistant cell lines, and the differential phosphorylation status of BAD also seemed to play a role in the development of cisplatin resistance. Since this is a new cisplatin-resistant Calu1 cell line, it is noteworthy that DNA fragmentation, apoptotic cell ratio and cytochrome c levels were most decreased in the CR-Calu1 cell line.

Platinum-based chemotherapies have long been used as a standard treatment in non-small cell lung cancer. However, cisplatin resistance is a major problem that restricts the use of cisplatin. Deregulated cell death mechanisms including apoptosis and autophagy could be responsible for the development of cisplatin resistance and miRNAs are the key regulators of these mechanisms. We aimed to analyse the effects of selected miRNAs in the development of cisplatin resistance and found that hsa-miR-15a-3p was one of the most significantly downregulated miRNAs conferring resistance to cisplatin in Calu1 epidermoid lung carcinoma cells. Only hsa-miR-15a-3p mimic transfection did not affect cell proliferation or cell death, though decreased cell viability was found when combined with cisplatin. We found that induced expression of hsa-miR-15a-3p via mimic transfection sensitised cisplatin-resistant cells to apoptosis and autophagy. Our results demonstrated that the apoptosis- and autophagy-inducing effects of hsa-miR-15a-3p might be due to suppression of BCL2, which exhibits a major connection with cell death mechanisms. This study provides new insights into the mechanism of cisplatin resistance due to silencing of the tumour suppressor hsa-miR-15a-3p and its possible contribution to apoptosis, autophagy and cisplatin resistance, which are the devil's triangle in determining cancer cell fate.

Our data suggest that common single nucleotide polymorphisms in the beta(1) and beta(2)-adrenergic receptors are significantly associated with idiopathic ventricular arrhythmias in Turkish population.