Sequence and expression variations in 23 genes involved in mitochondrial and non-mitochondrial apoptotic pathways and risk of oral leukoplakia and cancer

Role of microRNAs in regulation of doxorubicin and paclitaxel responses in lung tumor cells

Lung cancer as the leading cause of cancer related mortality is always one of the main global health challenges. Despite the recent progresses in therapeutic methods, the mortality rate is still significantly high among lung cancer patients. A wide range of therapeutic methods including chemotherapy, radiotherapy, and surgery are used to treat lung cancer. Doxorubicin (DOX) and Paclitaxel (TXL) are widely used as the first-line chemotherapeutic drugs in lung cancer. However, there is a significant high percentage of DOX/TXL resistance in lung cancer patients, which leads to tumor recurrence and metastasis. Considering, the side effects of these drugs in normal tissues, it is required to clarify the molecular mechanisms of DOX/TXL resistance to introduce the efficient prognostic and therapeutic markers in lung cancer. MicroRNAs (miRNAs) have key roles in regulation of different pathophysiological processes including cell division, apoptosis, migration, and drug resistance. MiRNA deregulations are widely associated with chemo resistance in various cancers. Therefore, considering the importance of miRNAs in chemotherapy response, in the present review, we discussed the role of miRNAs in regulation of DOX/TXL response in lung cancer patients. It has been reported that miRNAs mainly induced DOX/TXL sensitivity in lung tumor cells by the regulation of signaling pathways, autophagy, transcription factors, and apoptosis. This review can be an effective step in introducing miRNAs as the non-invasive prognostic markers to predict DOX/TXL response in lung cancer patients.

Association of caspase-1 gene polymorphisms with rheumatoid arthritis risk in a Chinese Han population

The goals of present research are to investigate if the genetic polymorphisms in the caspase-1 (CASP1) gene are associated with the risk of rheumatoid arthritis (RA) and the clinical characteristics of the illness in Han patients from China. Our team studied the CASP1 rs2409062 A/G polymorphisms in 1095 healthy controls and 805 RA patients, while the genotype was identified via a custom-by-design 48-Plex single nucleotide polymorphism (SNP) scan™ Kit. The mRNA expression levels of the CASP1 in 40 RA cases and 40 healthy controls were detected by qRT-PCR, while blood plasma levels of the CASP1 in 40 RA cases and 40 paired controls measured via ELISA. Our research showed that the CASP1 rs2409062 A/G polymorphisms were related to an elevated risk for RA. By stratified analysis, our team discovered a remarkably elevated RA risk in females sufferers, age ≥ 55, CRP-positive, or DAS28 < 3.20. In contrast to the control group, the mean level of CASP1 protein in the plasma of RA cases rised significantly. Moreover, RA cases displayed significantly greater levels of CASP1 mRNA versus the control group (P < 0.05). Those outcomes reveal that the CASP1 rs2409062 A/G gene polymorphisms are associated with an elevated risk for RA in a Chinese Han population.

Development and Validation of Autophagy-Related Gene Signature and Nomogram for Predicting Survival in Oral Squamous Cell Carcinoma

Background

Autophagy, a highly conserved self-digesting process, has been deeply involved in the development and progression of oral squamous cell carcinoma (OSCC). However, the prognostic value of autophagy-related genes (ARGs) for OSCC still remains unclear. Our study set out to develop a multigene expression signature based on ARGs for individualized prognosis assessment in OSCC patients.

Methods

Based on The Cancer Genome Atlas (TCGA) database, we identified prognosis-related ARGs through univariate COX regression analysis. Then we performed the least absolute shrinkage and selection operator (LASSO) regression analysis to identify an optimal autophagy-related multigene signature with the subsequent validation in testing set, GSE41613 and GSE42743 datasets.

Results

We identified 36 prognosis-related ARGs for OSCC. Subsequently, the multigene signature based on 13 prognostic ARGs was constructed and successfully divided OSCC patients into low and high-risk groups with significantly different overall survival in TCGA training set (p < 0.0001). The autophagy signature remained as an independent prognostic factor for OSCC in univariate and multivariate Cox regression analyses. The area under the curve (AUC) values of the receiver operating characteristic (ROC) curves for 1, 3, and 5-year survival were 0.758, 0.810, 0.798, respectively. Then the gene signature was validated in TCGA testing set, GSE41613 and GSE42743 datasets. Moreover, Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, and single-sample gene set enrichment analysis (ssGSEA) revealed the underlying biological characteristics and signaling pathways associated with this signature in OSCC. Finally, we constructed a nomogram by combining the gene signature with multiple clinical parameters (age, gender, TNM-stage, tobacco, and alcohol history). The concordance index (C-index) and calibration plots demonstrated favorable predictive performance of our nomogram.

Conclusion

In summary, we identified and verified a 13-ARGs prognostic signature and nomogram, which provide individualized prognosis evaluation and show insight for potential therapeutic targets for OSCC.

Molecular, genomic and mutational landscape of oral leukoplakia

Oral leukoplakia (OLK) and its more aggressive clinical variant proliferative verrucous leukoplakia (PVL) remain enigmatic disorders clinically and histopathologically. Despite decades of research into both, there has been only incremental advancement in our understanding of their aetiology and pathogenesis and only minimal improvement in effective management strategies. Currently, no specific prognostic genetic or molecular marker has been reported for leukoplakia. There is, however, an emerging body of evidence characterising the genomic and transcriptomic profile of OLK. Regardless of the significance of cellular and architectural features of OLK and PVL, it is clear from studies reported in this review that new emerging evidence points to the presence of premalignant molecular subtypes of leukoplakia which require further investigation. This up-to-date review explores the contemporary genomic, transcriptomic and mutational landscape of leukoplakia broadly, discusses concepts that may not be widely recognised or accepted and purposefully highlights studies with juxtaposed findings in an effort to challenge dogma. It also highlights the urgent need for a concerted international effort of original collaborative research which will only occur by pooling collective efforts, resources and intellect to define the molecular fingerprint of this enigmatic disorder, in the hope it will better inform diagnosis, stratification and treatment.

Role of Mitochondrial DNA (mtDNA) Variations in Cancer Development: A Systematic Review

mtDNA is the closed circular, ds-DNA present in mitochondria of eukaryotic cells and are inherited maternally. Besides being the power house of the cell, mitochondria are also responsible for the regulation of redox homeostasis, signaling, metabolism, immunity, survival and apoptosis. Lack of a 'Systematic Review' on mtDNA variations and cancers encouraged us to perform the present study. Pubmed', 'Embase' and 'Cochrane Library' databases were searched using keywords 'Mitochondrial DNA' OR 'mtDNA' OR 'mDNA' AND 'polymorphism' AND 'cancer' AND 'risk' to retrieve literature. Polymorphisms occupy first rank among mtDNA variations followed by CNV, MSI, mutations and hold a great potential to emerge as key predictors for human cancers.

BCL-w: apoptotic and non-apoptotic role in health and disease

The BCL-2 family of proteins integrates signals that trigger either cell survival or apoptosis. The balance between pro-survival and pro-apoptotic proteins is important for tissue development and homeostasis, while impaired apoptosis contributes to several pathologies and can be a barrier against effective treatment. BCL-w is an anti-apoptotic protein that shares a sequence similarity with BCL-X_L, and exhibits a high conformational flexibility. BCL-w level is controlled by a number of signaling pathways, and the repertoire of transcriptional regulators largely depends on the cellular and developmental context. As only a few disease-relevant genetic alterations of BCL2L2 have been identified, increased levels of BCL-w might be a consequence of abnormal activation of signaling cascades involved in the regulation of BCL-w expression. In addition, BCL-w transcript is a target of a plethora of miRNAs. Besides its originally recognized pro-survival function during spermatogenesis, BCL-w has been envisaged in different types of normal and diseased cells as an anti-apoptotic protein. BCL-w contributes to survival of senescent and drug-resistant cells. Its non-apoptotic role in the promotion of cell migration and invasion has also been elucidated. Growing evidence indicates that a high BCL-w level can be therapeutically relevant in neurodegenerative disorders, neuron dysfunctions and after small intestinal resection, whereas BCL-w inhibition can be beneficial for cancer patients. Although several drugs and natural compounds can bi-directionally affect BCL-w level, agents that selectively target BCL-w are not yet available. This review discusses current knowledge on the role of BCL-w in health, non-cancerous diseases and cancer.

Seleno-β-lactoglobulin (Se-β-Lg) induces mitochondria-dependant apoptosis in HepG2 cells

Selenium compounds have been widely investigated as novel anticancer agents due to high efficacy and selectivity against cancer cells in recent years. This study aimed to research the potential inhibitory effects of seleno-β-lactoglobulin (Se-β-Lg) on HepG2 cells in vitro. MTT results demonstrated that the synthetized Se-β-Lg exhibited strong antitumor activity on HepG2 cells with few side effects on human normal cells (LO2) and relatively weaker cytotoxic effects compared to inorganic selenium (SeO₂). Scanning electron microscope (SEM), hoechst 33342/PI double staining, annexin V-FITC/PI staining and cell cycle detection results showed that Se-β-Lg could induce the apoptosis of HepG2 cells via arresting them in S and G2/M phases and lead to the obvious morphological changes (loss of adhesion, cell shrinkage, and membrane blebbing, membrane permeabilities and DNA fragmentation). Besides, JC-1 staining, western blotting (WB) and polymerase chain reaction (PCR) results showed that Se-β-Lg could gradually destroy the mitochondrial membrane potential of HepG2 cells, and finally resulting in the mitochondria-dependant apoptosis via up-regulation of Bax, Cytochrome c, Caspase-3 and down-regulation of Bcl-2. Our data could provide a theoretical basis for practical application of Se-β-Lg in food and drug industries.