miR-29a expression negatively correlates with Bcl-2 levels in colorectal cancer and is correlated with better prognosis.

MicroRNAs (miRNAs) are a class of small non-coding RNAs that act as important regulators of gene expression, involved in various biological pathways. Aberrant miRNAs expression is associated with the onset and progression of colorectal cancer (CRC). The aim of this study was to investigate the correlation between five miRNAs (miR-29a, miR-101, miR-125b, miR-146a, and miR-155), found to be deregulated in tissue samples of CRC patients, and clinicopathological characteristics and histological markers.

Editorial: Mitochondrial Research: Yeast and Human Cells as Models 2.0.

Mitochondrial research stands at the forefront of modern biology, unraveling the intricate mechanisms governing cellular metabolism, energy production, and disease pathogenesis [...

Carnation Italian Ringspot Virus p36 Expression Induces Mitochondrial Fission and Respiratory Chain Complex Impairment in Yeast.

Positive-strand RNA virus replication invariably occurs in association with host cell membranes, which are induced to proliferate and rearrange to form vesicular structures where the virus replication complex is assembled. In particular, carnation Italian ringspot virus (CIRV) replication takes place on the mitochondrial outer membrane in plant and yeast cells. In this work, the model host was used to investigate the effects of CIRV p36 expression on the mitochondrial structure and function through the determination of mitochondrial morphology, mitochondrial respiratory parameters, and respiratory chain complex activities in p36-expressing cells.

The role of miRNA in colorectal cancer diagnosis: A pilot study.

Despite recent advances in diagnosis and treatment, colorectal cancer (CRC) remains the third most common cancer worldwide, and has both a poor prognosis and a high recurrence rate, thus indicating the need for new, sensitive and specific biomarkers. MicroRNAs (miRNAs/miRs) are important regulators of gene expression, which are involved in numerous biological processes implicated in tumorigenesis. The objective of the present study was to investigate the expression of miRNAs in plasma and tissue samples from patients with CRC, and to examine their potential as CRC biomarkers.

Mitochondrial Research: Yeast and Human Cells as Models.

The evolution of complex eukaryotes would have been impossible without mitochondria, key cell organelles responsible for the oxidative metabolism of sugars and the bulk of ATP production [...

Signaling Sustains Mitochondrial Respiratory Capacity in -Dependent Osmoadaptation.

Mitochondrial -dependent retrograde signaling, whose regulators have been characterized in , plays a recognized role under various environmental stresses. Of special significance, the activity of the transcriptional complex Rtg1/3 has been shown to be modulated by Hog1, the master regulator of the high osmolarity glycerol pathway, in response to osmotic stress. The present work focuses on the role of signaling in salt-induced osmotic stress and its interaction with .

Analysis of Mitochondrial Retrograde Signaling in Yeast Model Systems.

Mitochondrial retrograde signaling is a mitochondria-to-nucleus communication pathway, conserved from yeast to humans, by which dysfunctional mitochondria relay signals that lead to cell stress adaptation in physiopathological conditions via changes in nuclear gene expression. The most comprehensive picture of components and regulation of retrograde signaling has been obtained in Saccharomyces cerevisiae, where retrograde-target gene expression is regulated by RTG genes. In this chapter, we describe methods to measure mitochondrial retrograde pathway activation at the level of mRNA and protein products in yeast model systems, including cell suspensions and microcolonies.

Epigenetic silencing of the ubiquitin ligase subunit FBXL7 impairs c-SRC degradation and promotes epithelial-to-mesenchymal transition and metastasis.

Epigenetic plasticity is a pivotal factor that drives metastasis. Here, we show that the promoter of the gene that encodes the ubiquitin ligase subunit FBXL7 is hypermethylated in advanced prostate and pancreatic cancers, correlating with decreased FBXL7 mRNA and protein levels. Low FBXL7 mRNA levels are predictive of poor survival in patients with pancreatic and prostatic cancers.

6-Thioguanine and Its Analogs Promote Apoptosis of Castration-Resistant Prostate Cancer Cells in a BRCA2-Dependent Manner.

: Mutations in the oncosuppressor gene () predispose to aggressive forms of prostate cancer which show poor response to taxane-based therapy, the standard treatment for castration-resistant, aggressive prostate cancer. Herein, we addressed the question whether changes in BRCA2 expression, a potential surrogate marker for BRCA2 activity, may affect the response of castration-resistant prostate cancer cells to 6-thioguanine (6-TG), a thiopurine used in the treatment of haematological malignancies. : Yeast, normal prostate cells and castration-resistant prostate cancer cells were treated with 6-TG or its analogues, in presence or absence of paclitaxel, or with olaparib, a poly-(ADP-ribose) polymerase (PARP) inhibitor currently in clinical trials for treatment of metastatic castration-resistant prostate cancer, and cell proliferation, apoptosis and androgen receptor (AR) levels were measured.

Acid Stress Triggers Resistance to Acetic Acid-Induced Regulated Cell Death through Activation Which Requires in Yeast.

Acid stress causes resistance to acetic acid-induced regulated cell death (AA-RCD) in budding yeast, resulting in catalase activation. In order to explore the molecular determinants of evasion of AA-RCD triggered by acid stress adaptation, we studied the involvement and the possible interplay of the master regulator of transcription high-osmolarity glycerol 1 () and , a positive regulator of the -dependent mitochondrial retrograde signaling. Viability, DNA fragmentation, and ROS accumulation have been analyzed in wild-type and mutant cells lacking and/or .

Mitochondria-cytosol-nucleus crosstalk: learning from Saccharomyces cerevisiae.

Mitochondria are key cell organelles with a prominent role in both energetic metabolism and the maintenance of cellular homeostasis. Since mitochondria harbor their own genome, which encodes a limited number of proteins critical for oxidative phosphorylation and protein translation, their function and biogenesis strictly depend upon nuclear control. The yeast Saccharomyces cerevisiae has been a unique model for understanding mitochondrial DNA organization and inheritance as well as for deciphering the process of assembly of mitochondrial components.

Guidelines and recommendations on yeast cell death nomenclature.

Elucidating the biology of yeast in its full complexity has major implications for science, medicine and industry. One of the most critical processes determining yeast life and physiology is cel-lular demise. However, the investigation of yeast cell death is a relatively young field, and a widely accepted set of concepts and terms is still missing.

Mitochondrial Dysfunction: A Novel Potential Driver of Epithelial-to-Mesenchymal Transition in Cancer.

Epithelial-to-mesenchymal transition (EMT) allows epithelial cancer cells to assume mesenchymal features, endowing them with enhanced motility and invasiveness, thus enabling cancer dissemination and metastatic spread. The induction of EMT is orchestrated by EMT-inducing transcription factors that switch on the expression of "mesenchymal" genes and switch off the expression of "epithelial" genes. Mitochondrial dysfunction is a hallmark of cancer and has been associated with progression to a metastatic and drug-resistant phenotype.

SLC25A10 biallelic mutations in intractable epileptic encephalopathy with complex I deficiency.

Mitochondrial diseases are a plethora of inherited neuromuscular disorders sharing defects in mitochondrial respiration, but largely different from one another for genetic basis and pathogenic mechanism. Whole exome sequencing was performed in a familiar trio (trio-WES) with a child affected by severe epileptic encephalopathy associated with respiratory complex I deficiency and mitochondrial DNA depletion in skeletal muscle. By trio-WES we identified biallelic mutations in SLC25A10, a nuclear gene encoding a member of the mitochondrial carrier family.

The transcription factors or are required for RTG pathway activation and evasion from yeast acetic acid-induced programmed cell death in raffinose.

Yeast grown on glucose undergoes programmed cell death (PCD) induced by acetic acid (AA-PCD), but evades PCD when grown in raffinose. This is due to concomitant relief of carbon catabolite repression (CCR) and activation of mitochondrial retrograde signaling, a mitochondria-to-nucleus communication pathway causing up-regulation of various nuclear target genes, such as , encoding peroxisomal citrate synthase, dependent on the positive regulator in response to mitochondrial dysfunction. CCR down-regulates genes mainly involved in mitochondrial respiratory metabolism.

Heterologous expression of carnation Italian ringspot virus p36 protein enhances necrotic cell death in response to acetic acid in Saccharomyces cerevisiae.

A universal feature of the replication of positive-strand RNA viruses is the association with intracellular membranes. Carnation Italian ringspot virus (CIRV) replication in plants occurs in vesicles derived from the mitochondrial outer membrane. The product encoded by CIRV ORF1, p36, is required for targeting the virus replication complex to the outer mitochondrial membrane both in plant and yeast cells.

Silencing of BRCA2 to Identify Novel BRCA2-regulated Biological Functions in Cultured Human Cells.

Silencing of the tumor suppressor protein BRCA2 and its detection by conventional biochemical analyses represent a great technical challenge owing to the large size of the human BRCA2 protein (approximately 390 kDa). We report modifications of standard siRNA transfection and immunoblotting protocols to silence human BRCA2 and detect endogenous BRCA2 protein, respectively, in human epithelial cell lines. Key steps include a high siRNA to transfection reagent ratio and two subsequent rounds of siRNA transfection within the same experiment.

Proteome and metabolome profiling of wild-type and YCA1-knock-out yeast cells during acetic acid-induced programmed cell death.

Unlabelled: Caspase proteases are responsible for the regulated disassembly of the cell into apoptotic bodies during mammalian apoptosis. Structural homologues of the caspase family (called metacaspases) are involved in programmed cell death in single-cell eukaryotes, yet the molecular mechanisms that contribute to death are currently undefined. Recent evidence revealed that a programmed cell death process is induced by acetic acid (AA-PCD) in Saccharomyces cerevisiae both in the presence and absence of metacaspase encoding gene YCA1.

Differential proteome-metabolome profiling of YCA1-knock-out and wild type cells reveals novel metabolic pathways and cellular processes dependent on the yeast metacaspase.

The yeast Saccharomyces cerevisiae expresses one member of the metacaspase Cys protease family, encoded by the YCA1 gene. Combination of proteomics and metabolomics data showed that YCA1 deletion down-regulated glycolysis, the TCA cycle and alcoholic fermentation as compared with WT cells. Δyca1 cells also showed a down-regulation of the pentose phosphate pathway and accumulation of pyruvate, correlated with higher levels of certain amino acids found in these cells.

Yeast as a tool to study mitochondrial retrograde pathway en route to cell stress response.

Mitochondrial retrograde signaling is a mitochondria-to-nucleus communication pathway, conserved from yeast to humans, by which dysfunctional mitochondria relay signals that lead to cell stress adaptation in physiopathological conditions by changes in nuclear gene expression. The best comprehension of components and regulation of retrograde signaling have been obtained in Saccharomyces cerevisiae, where retrograde target gene expression is regulated by RTG genes. In this chapter, we describe the methods to measure mitochondrial retrograde pathway activation in yeast cells by monitoring the mRNA levels of RTG target genes, such as those encoding for peroxisomal citrate synthase, aconitase, and NAD(+)-specific isocitrate dehydrogenase subunit 1, as well as the phosphorylation status of Rtg1/3p transcriptional factor which controls RTG target gene transcription.

Mitochondrial dysfunction in cancer chemoresistance.

Mitochondrial dysfunction has been associated with cancer development and progression. Recent evidences suggest that pathogenic mutations or depletion of the mitochondrial genome can contribute to development of chemoresistance in malignant tumors. In this review we will describe the current knowledge on the role of mitochondrial dysfunction in the development of chemoresistance in cancer.