Polypyrimidine tract-binding protein 1 (PTBP1) is an RNA-binding protein that regulates alternative splicing and primarily acts as a splicing repressor. Previous studies have shown that PTBP1 is closely linked to cancer metabolism through regulation by miR-133b and miR-124, which inhibit PTBP1 expression and modulate the splicing of the pyruvate kinase muscle (PKM) gene. Increased PTBP1 expression promotes PKM2 production and enhances glycolysis-dependent metabolism, a hallmark of cancer known as the Warburg effect. Clinical and experimental analyses were conducted to investigate the role of PTBP1 in breast cancer (BC). In silico investigations using The Cancer Genome Atlas (TCGA) and Molecular Taxonomy of Breast Cancer International Consortium (METABRIC) datasets revealed a significant association between PTBP1 overexpression and poor prognosis. In vitro, PTBP1 knockdown in BC cell lines (MCF7, SK-BR-3, and MDA-MB-231) increased PKM1 expression and the PKM1/PKM2 ratio, leading to reduced cell proliferation. ATP production increased in MCF7 and SK-BR-3 cells, but not in MDA-MB-231. Although NADH levels were elevated in MCF7 and MDA-MB-231 cells, lactate accumulation was most prominent in MDA-MB-231 cells. qRT-PCR analysis of surgical BC specimens confirmed significantly higher PTBP1 expression in tumour tissues than in adjacent normal breast tissues, with expression positively correlating with tumour grade. These findings collectively demonstrate that PTBP1 is overexpressed in BC and drives cancer-specific metabolic reprogramming associated with the Warburg effect. Therefore, PTBP1 may act as an oncogenic regulator of breast cancer metabolism and serve as a potential therapeutic target.

The following reference [8] has been retracted and has therefore been removed from the original publication [...]

Cancer cells preferentially rely on aerobic glycolysis, known as the Warburg effect, to support growth and survival. We previously demonstrated that polypyrimidine tract-binding protein 1 (PTBP1) maintains PKM2 dominance by regulating pyruvate kinase isoform splicing, sustaining the Warburg phenotype. PTBP1 suppression shifts metabolism toward PKM1 dominance, enhancing oxidative phosphorylation, reactive oxygen species (ROS) production, apoptosis, and antitumor immunity. Thirteen chemically modified siR-PTBP1 derivatives targeting either the coding region or the 3'-untranslated region (3'-UTR) of PTBP1 mRNA were synthesized and evaluated in colorectal cancer cell lines. Cytotoxicity, protein expression, oxidative stress, and metabolic alterations were assessed using cell-based assays, immunoblotting, and metabolomic analysis. siRNA stability was evaluated following nuclease exposure and quantified by TaqMan RT-qPCR. siRNAs targeting the 3'-UTR more effectively suppressed PTBP1 expression and increased the PKM1/PKM2 ratio than coding-region-targeting siRNAs. Among them, derivative 2-6 showed the strongest cytotoxicity with oxidative stress and apoptosis. Metabolomic profiling demonstrated altered glycolytic flux and preserved pentose phosphate pathway intermediates with activated redox responses, while adenylate and guanylate energy charges remained viable, indicating metabolic stress without energy collapse. Tricarboxylic acid cycle metabolites were elevated, consistent with enhanced oxidative phosphorylation. Derivative 2-6 showed resistance to nuclease-mediated degradation. Direct PKM2 knockdown did not induce comparable cytotoxicity. Chemically modified siR-PTBP1, particularly derivative 2-6, induces a metabolically vulnerable state characterized by oxidative imbalance, leading to apoptosis. These findings identify PTBP1 as a key regulator of the Warburg effect and support siRNA-based metabolic targeting as a therapeutic strategy.

Oral melanoma is one of the most devastating cancers in dogs. We previously developed a novel agent extracted from Japanese butterbur shoots and its petasin derivatives demonstrated anti-proliferative activity in canine oral melanoma cells. The aim of this study was to evaluate the safety and clinical efficacy of the butterbur shoot extract (BSE) in dogs with oral melanoma as a combined phase 1 and 2 study. All enrolled dogs underwent radiation therapy or surgery as local therapy before BSE administration. We enrolled nine dogs in the phase 1 study, and BSE was orally administered at doses escalating from 50 to 200 mg/kg. Grade 1 alanine aminotransferase elevation and diarrhoea were observed in each dog. We determined that 200 mg/kg BSE was safe to administer. We subsequently administered it to sixteen dogs with stage 3 oral melanoma in the phase 2 study. Their progression-free survival and overall survival were compared with those of the historical controls, and adverse events were assessed. BSE administration significantly extended overall survival but did not prolong progression-free survival. No dose-limiting toxicities were observed. These results indicate that 200 mg/kg of BSE is safe to administer and may improve the outcome of canine oral melanoma.

We investigated whether miR143#12, a synthesized chemically modified miR-143-3p derivative, exerts therapeutic effects on acute myocardial infarction (AMI). Sprague–Dawley rats and Japanese white rabbits underwent 30 min of coronary occlusion followed by 2 weeks of reperfusion. The rat AMI model was intravenously administered with control miRNA (9 μg/kg), 3 μg/kg or 9 μg/kg of miR143#12 1 h after reperfusion, while the rabbit AMI model was intravenously administered with control miRNA (9 μg/kg) or 9 μg/kg of miR143#12. In the rat and rabbit AMI models, 9 μg/kg of miR143#12 significantly reduced infarct sizes and significantly improved cardiac function including LVEF and LVFS at 2 weeks. The tissue miR143 levels in infarct areas significantly decreased after AMI in both models. Electron microscopic study and immunohistochemistry suggested that miR143#12 suppressed autophagic cell death caused by AMI and induced neoangiogenesis in the infarct border. In cultured rat H9c2 cells, miR143#12 significantly inhibited H2O2-induced autophagic cell death by decreasing ROS levels and increased viable cell numbers more than the control by silencing COX-1, -2, and ATG7. Replacement treatment with miR143#12 in the infarct areas, where the expression levels of miR143 were significantly decreased, has a beneficial effect on AMI by silencing COX-1 and -2.

Extracellular vesicles (EVs) are nanoscale entities secreted by various cells, encapsulating various nucleic acids and proteins that play important roles in cellular activities. Although rice bran is known for its richness in phytochemicals such as tocopherol and tocotrienol, the distribution of these compounds within EVs has not been extensively studied. The objective of this study was to detect and analyze the presence of vitamin E in EVs extracted from rice bran. We investigated several EV extraction methods, including rotation, vortex mixing, and ultrasonication, followed by post-extraction techniques such as ultracentrifugation, ultrafiltration, and lyophilization. Vitamin E in the EVs from rice bran was analyzed using LC-FLD. This study is the first to identify tocopherol and tocotrienol in rice bran-derived EVs. Our results indicate that ultracentrifugation followed by rotation is the most effective method for the preparation of rice bran-derived EVs. Notably, the vitamin E profile in EVs varies depending on the preparation method and differs from that in rice bran extracts. The pronounced presence of vitamin E in EVs suggests unique pharmacokinetics and underscores the potential of EVs as carriers for drug delivery systems. This study not only confirms the presence of vitamin E in EVs, but also underscores the potential of EVs and their phytochemical content for therapeutic applications.

MicroRNA(miR)-143 and miR-145 are mainly expressed in vascular smooth muscle cells. However, the relationship between plasma miR-143 or miR-145 levels and the left ventricular (LV) function in patients with heart diseases remains unclear. Blood samples were taken from the antecubital vein in patients with heart diseases (n = 52), such as coronary artery disease, old myocardial infarction, cardiomyopathy, and valvular heart disease, and controls without heart diseases (n = 22). We measured plasma miR-143 and -145 levels by quantitative RT–PCR using TaqMan MicroRNA Assays and THUNDERBIRD Probe qPCR Mix. Plasma BNP levels were also measured. Echocardiography was performed to measure the LV ejection fraction (LVEF) and LV dilation. Plasma miR-143 and miR-145 levels were significantly higher in patients with heart diseases than in controls, respectively. Plasma miR-143 and miR-145 levels were significantly higher in patients with LVEF < 50

A progressive subclass of early-stage non-muscle-invasive bladder cancer (NMIBC) frequently recurs and progress into invasive carcinoma, thus decreasing the overall survival rate of NMIBC. However, therapeutic development for progressive NMIBC has been challenging due to the lack of molecularly validated in vivo models and agents targeting its genetic vulnerability. We herein molecularly characterized an interventional model of progressive NMIBC and revealed the principal functions and therapeutic potential of microRNA-145 (miR-145) in early bladder tumorigenesis. N-butyl-N-(4-hydroxybutyl)nitrosamine-induced premalignant lesions (BiPLs) in rats exhibited downregulated expression of miR-145 as well as highly similar mutation/expression profiles to those of the human progressive NMIBC subclass with the worst prognosis. The expression patterns of miR-145 inversely correlated with those of BC-related oncogenes in BiPLs. We also demonstrated that miR-145 dominantly regulated interferon pathways and c-Myc expression, which play a crucial role in the pathogenesis of progressive NMIBC. Furthermore, we demonstrated that miR-145 replacement with a novel miR-145-based intravesical agent (miR-145S1) significantly inhibited the progression of BiPLs in vivo. These results provide insights into the essential role of miR-145 as the earliest-acting oncogenic driver of bladder tumorigenesis as well as a validated interventional model and novel miR-145-based nucleic acid therapeutic agent for progressive NMIBC.

BACKGROUND MicroRNA (miR)-143 and miR-145 are non-coding RNAs present in smooth muscle cells and the heart. However, their behavior and physiological role in patients with acute myocardial infarction (AMI) have not been clarified.Methods and Results: Plasma miR-143 and miR-145 concentrations were measured on Day 0 (on admission) and on Day 7 in AMI patients who could be followed up for 6 months (n=25). The control group consisted of subjects without significant coronary stenosis (n=20). Blood samples were collected from the antecubital vein, and plasma miR-143 and miR-145 concentrations were measured by quantitative reverse transcription-polymerase chain reaction. In AMI patients (n=25), left ventricular ejection fraction (LVEF) was measured by echocardiography in the acute and chronic (6 months) phases. On Day 7, plasma miR-143 and miR-145 concentrations were significantly higher in AMI patients than in the control group and on Day 0 in AMI patients. Plasma miR-143 and miR-145 concentrations increased significantly from Day 0 to Day 7. The increase in plasma miR-143 concentrations (∆miR-143) in the acute phase was positively correlated with the increase in LVEF in the chronic phase. Among many factors, only ∆miR-143 was favorably correlated with left ventricle (LV) functional recovery in the chronic phase. CONCLUSIONS An increase in plasma miR-143 concentrations in the acute phase may be a biomarker predicting recovery of LV function in the chronic phase in AMI patients.