Systematic Analysis of FASTK Gene Family Alterations in Cancer

High expression of novel biomarker TBRG4 promotes the progression and invasion of oral squamous cell carcinoma

BACKGROUND

Transforming growth factor β regulator 4 (TBRG4) is a potential prognostic indicator in various cancers, especially squamous cell carcinomas, and is associated with disease amelioration and poor outcomes. The study aimed to assess the expression pattern of TBRG4 in patients with operable oral squamous cell carcinoma (OSCC) to understand its role in tumour progression using indicators of disease outcome like tumour stage, grade, nodal metastasis, and pattern of invasion.

METHODS

TBRG4 expression was assessed by analyzing 51 cancer and adjacent non-cancerous tissues of OSCC patients using quantitative real-time PCR, and Western blot. TBRG4 expression was also analysed in The Cancer Genome Atlas Head-Neck Squamous Cell Carcinoma (TCGA-HNSC) dataset using the UALCAN tool (http://ualcan.path.uab.edu/). The relationship between TBRG4 expression and the patient's prognosis was analysed using Kaplan-Meier plotter.

RESULTS

Both mRNA and protein levels of TBRG4 were significantly increased in OSCC tissues. The TBGR4 expression was significantly associated with advanced stages (III and IV) and the worst pattern of invasion (WPOI-4 and 5). High TBRG4 expression was also significantly associated with reduced overall survival (p = 0.011). In addition, the analysis of TBRG4 gene expression and clinical data from TCGA, identified that TBRG4 was highly expressed in HPV negative OSCC patients and positively correlated with worst overall survival.

CONCLUSION

The present study suggests that the high expression of TBRG4 might serve as a novel prognostic biomarker for HPV-negative OSCC, which can be validated by future additional investigations in larger cohorts along with functional studies.

Microbial dysbiosis and the host airway epithelial response: insights into HIV-associated COPD using multi'omics profiling

BACKGROUND

People living with HIV (PLWH) are at increased risk of developing Chronic Obstructive Pulmonary Disease (COPD) independent of cigarette smoking. We hypothesized that dysbiosis in PLWH is associated with epigenetic and transcriptomic disruptions in the airway epithelium.

METHODS

Airway epithelial brushings were collected from 18 COPD + HIV + , 16 COPD - HIV + , 22 COPD + HIV - and 20 COPD - HIV - subjects. The microbiome, methylome, and transcriptome were profiled using 16S sequencing, Illumina Infinium Methylation EPIC chip, and RNA sequencing, respectively. Multi 'omic integration was performed using Data Integration Analysis for Biomarker discovery using Latent cOmponents. A correlation > 0.7 was used to identify key interactions between the 'omes.

RESULTS

The COPD + HIV -, COPD -HIV + , and COPD + HIV + groups had reduced Shannon Diversity (p = 0.004, p = 0.023, and p = 5.5e-06, respectively) compared to individuals with neither COPD nor HIV, with the COPD + HIV + group demonstrating the most reduced diversity. Microbial communities were significantly different between the four groups (p = 0.001). Multi 'omic integration identified correlations between Bacteroidetes Prevotella, genes FUZ, FASTKD3, and ACVR1B, and epigenetic features CpG-FUZ and CpG-PHLDB3.

CONCLUSION

PLWH with COPD manifest decreased diversity and altered microbial communities in their airway epithelial microbiome. The reduction in Prevotella in this group was linked with epigenetic and transcriptomic disruptions in host genes including FUZ, FASTKD3, and ACVR1B.

Cardiac Myocyte-Specific Overexpression of FASTKD1 Prevents Ventricular Rupture After Myocardial Infarction

Background The mitochondrial mRNA-binding protein FASTKD1 (Fas-activated serine/threonine [FAST] kinase domain-containing protein 1) protects myocytes from oxidative stress in vitro. However, the role of FASTKD1 in the myocardium in vivo is unknown. Therefore, we developed cardiac-specific FASTKD1 transgenic mice to test the effects of this protein on experimental myocardial infarction (MI). Methods and Results Transgenic mouse lines with cardiac myocyte-specific overexpression of FASTKD1 to varying degrees were generated. These mice displayed normal cardiac morphological features and function at the gross and microscopic levels. Isolated cardiac mitochondria from all transgenic mouse lines showed normal mitochondrial function, ATP levels, and permeability transition pore activity. Male nontransgenic and transgenic mice from the highest-expressing line were subjected to 8 weeks of permanent coronary ligation. Of nontransgenic mice, 40% underwent left ventricular free wall rupture within 7 days of MI compared with 0% of FASTKD1-overexpressing mice. At 3 days after MI, FASTKD1 overexpression did not alter infarct size. However, increased FASTKD1 resulted in decreased neutrophil and increased macrophage infiltration, elevated levels of the extracellular matrix component periostin, and enhanced antioxidant capacity compared with control mice. In contrast, markers of mitochondrial fusion/fission and apoptosis remained unaltered. Instead, transcriptomic analyses indicated activation of the integrated stress response in the FASTKD1 transgenic hearts. Conclusions Cardiac-specific overexpression of FASTKD1 results in viable mice displaying normal cardiac morphological features and function. However, these mice are resistant to MI-induced cardiac rupture and display altered inflammatory, extracellular matrix, and antioxidant responses following MI. Moreover, these protective effects were associated with enhanced activation of the integrated stress response.

Identification of Novel Cytochrome C1 (CYC1) Gene Expression in Oral Squamous Cell Carcinoma- An Evaluative Study

Introduction

Cytochrome C1 (CYC1) is an important subunit of mitochondrial complex III and plays a vital role in oxidative phosphorylation (OXPHOS) and reactive oxygen species generation. Overexpression of the CYC1 gene has been implicated in cancer development and its prognosis previously, but unexplored in head-and-neck squamous cell carcinomas (HNSCC), especially oral squamous cell carcinoma (OSCC).

Materials and Methods

CYC1 m-RNA expression and gene alterations were assessed using the Cancer Genome Atlas dataset in HNSCC and validated in OSCC tissues using real-time polymerase chain reaction (RT-PCR). The protein-protein interaction (PPI) network and functional enrichment pathways were also analysed.

Results

A thorough analysis of the TCGA (The Cancer Genome Atlas) database revealed that CYC1 was overexpressed in the HNSCC cases and the increased expression correlated with several parameters which involve the prediction of advanced diseases such as histopathological grade, tumour-node-metastasis staging, and nodal metastases (P < 0.05). The expression of CYC1 was validated using RT-PCR showing significant upregulation (P < 0.05) in OSCC tissue samples compared to the normal tissue counterparts. PPI network and functional analysis show the prominent role of CYC1 in OXPHOS, especially in electron transport chain III complex regulation.

Discussion

The study revealed that CYC1 is highly expressed in HNSCC, and is validated in the OSCC patient tissue samples compared to the normal counterparts and associated with advanced disease stages and grade of the tumour. CYC1 could be a novel promising therapeutic and prognostic marker in HNSCC, especially in OSCC.

How RNases Shape Mitochondrial Transcriptomes

Mitochondria are the power houses of eukaryote cells. These endosymbiotic organelles of prokaryote origin are considered as semi-autonomous since they have retained a genome and fully functional gene expression mechanisms. These pathways are particularly interesting because they combine features inherited from the bacterial ancestor of mitochondria with characteristics that appeared during eukaryote evolution. RNA biology is thus particularly diverse in mitochondria. It involves an unexpectedly vast array of factors, some of which being universal to all mitochondria and others being specific from specific eukaryote clades. Among them, ribonucleases are particularly prominent. They play pivotal functions such as the maturation of transcript ends, RNA degradation and surveillance functions that are required to attain the pool of mature RNAs required to synthesize essential mitochondrial proteins such as respiratory chain proteins. Beyond these functions, mitochondrial ribonucleases are also involved in the maintenance and replication of mitochondrial DNA, and even possibly in the biogenesis of mitochondrial ribosomes. The diversity of mitochondrial RNases is reviewed here, showing for instance how in some cases a bacterial-type enzyme was kept in some eukaryotes, while in other clades, eukaryote specific enzymes were recruited for the same function.

FASTK family of genes linked to cancer

Fas Activated Serine/Threonine Kinase (FASTK) family is a protein family encoded in the nuclear genome that spans the mitochondria and executes numerous functions, and consists of FASTK, the founding member along with 5 homologous proteins FASTKD1-5. Up regulation of FASTK family members have not only been implicated in tumour progression and invasion but also in increased resistance to chemotherapy proven by their knockdown leading to increased sensitivity to drugs. Thus, this review reports the implication of FASTK proteins in cancer and hence provides a scope to emphasise the role of these proteins in Oral Cancer.

Targeting Mitochondrial Protein Expression as a Future Approach for Cancer Therapy

Extensive metabolic remodeling is a fundamental feature of cancer cells. Although early reports attributed such remodeling to a loss of mitochondrial functions, it is now clear that mitochondria play central roles in cancer development and progression, from energy production to synthesis of macromolecules, from redox modulation to regulation of cell death. Biosynthetic pathways are also heavily affected by the metabolic rewiring, with protein synthesis dysregulation at the hearth of cellular transformation. Accumulating evidence in multiple organisms shows that the metabolic functions of mitochondria are tightly connected to protein synthesis, being assembly and activity of respiratory complexes highly dependent on de novo synthesis of their components. In turn, protein synthesis within the organelle is tightly connected with the cytosolic process. This implies an entire network of interactions and fine-tuned regulations that build up a completely under-estimated level of complexity. We are now only preliminarily beginning to reconstitute such regulatory level in human cells, and to perceive its role in diseases. Indeed, disruption or alterations of these connections trigger conditions of proteotoxic and energetic stress that could be potentially exploited for therapeutic purposes. In this review, we summarize the available literature on the coordinated regulation of mitochondrial and cytosolic mRNA translation, and their effects on the integrity of the mitochondrial proteome and functions. Finally, we highlight the potential held by this topic for future research directions and for the development of innovative therapeutic approaches.