Current Issues in Molecular Biology最新文献

Inflammatory bowel disease (IBD) and rheumatoid arthritis (RA) are chronic inflammatory diseases that share immune dysregulation and mitochondrial dysfunction. Understanding the molecular mechanisms linking these diseases to mitochondrial dysfunction is crucial for developing novel diagnostic and therapeutic strategies. Datasets related to IBD and RA were obtained from the Gene Expression Omnibus database. Differentially expressed mitochondrial dysfunction-related genes (MDRGs) were identified using differential expression analysis. Weighted gene co-expression network analysis was performed to identify crosstalk genes (CGs). Logistic regression and support vector machine (SVM) models were constructed using least absolute shrinkage and selection operator regression to identify hub genes. Additionally, the differential expression and diagnostic value of the hub genes were verified using quantitative reverse transcriptase-polymerase chain reaction and validation sets. Finally, immune infiltration analysis was conducted to assess the role of immune cells in IBD and RA. A total of 87 CGs associated with mitochondrial dysfunction were identified between IBD and RA, among which PDIA4 and DUSP6 were identified as hub genes. Twenty proteins, including ERO1A, MAPK7, and P4HB, were identified as key proteins that interacted with PDIA4 and DUSP6. The area under the curve (AUC) of the ROC curves for IBD and RA based on the DUSP6 and PDIA4 diagnostic models were 0.664 and 0.856, respectively. The qRT-PCR results indicated that PDIA4 and DUSP6 were overexpressed in IBD and RA. Seven immune cell types, including activated B cells, activated dendritic cells, and eosinophils showed significant differences in the IBD and RA groups. Our findings highlight the close association between IBD, RA, and mitochondrial dysfunction. PDIA4 and DUSP6 may serve as potential biomarkers of mitochondrial dysfunction in patients with IBD and RA.

Thymic carcinoma (TC) is a rare and aggressive malignancy with poor prognosis, and its genomic landscape remains incompletely defined. Identifying the somatic alterations that shape TC biology is essential for improving diagnostic precision, developing targeted therapies, and informing early detection strategies. We performed a retrospective genomic analysis of 141 TC tumor specimens from 134 patients using de-identified data from the American Association for Cancer Research (AACR) Project GENIE^® database. Somatic mutations and copy number alterations (CNAs) were characterized, and statistical analyses were conducted to evaluate associations with patient demographics (sex, race) and tumor site (primary vs. metastatic). The cohort was predominantly male (56.7%) and White (56.7%). The most frequently altered genes were TP53 (27.7%), CYLD (17.6%), and CDKN2A (12.1%). Recurrent homozygous deletions at chromosome 9p21.3 involving CDKN2A and CDKN2B were common. Sex-stratified analysis revealed several significant male-specific alterations. Although the Pacific Islander subgroup was small (n = 2), preliminary analysis suggested enrichment of alterations in key cancer-associated genes, including TP53, BRCA1, and STAT5B, underscoring the need for diverse representation in TC genomics. Notably, MTOR mutations were significantly enriched in a subset of local recurrences and lymph node metastases (n = 3; q = 0.013), suggesting a potential role in disease progression. This large-scale genomic analysis reinforces the central involvement of TP53, cell-cycle control, and chromatin-modifying pathways in TC. The identification of sex-associated and race-associated mutational patterns, together with the enrichment of MTOR alterations in recurrent and metastatic disease, highlights biologically plausible mechanisms of progression and potential therapeutic vulnerabilities. These findings support the value of comprehensive genomic profiling in TC and emphasize the need for prospective, multi-omic studies to validate these observations and guide the development of more personalized treatment strategies.

Alcohol-associated liver disease (ALD) contributes substantially to the global burden of cirrhosis and liver-related mortality, driven by ethanol metabolism, oxidative stress, and dysregulated immune signaling. Despite rapidly growing evidence implicating interferon regulatory factors (IRFs) in ALD pathogenesis, an integrated framework linking ethanol-induced danger signals to cell-type-specific IRF programs is lacking. In this comprehensive review, we summarize current knowledge on IRF-centered signaling networks in ALD, spanning DAMP-PAMP sensing, post-translational IRF regulation, and downstream inflammatory, metabolic, and fibrogenic outcomes across various cell types in the liver, including hepatocytes and immune-related cells such as Kupffer cells, monocyte-derived macrophages, dendritic cells, T cells, hepatic stellate cells (HSC), and neutrophils. We also focus on how ethanol-driven DAMP and PAMP signals activate TLR4, TLR9, and cGAS-STING pathways to engage a coordinated network of IRFs-including IRF1, IRF3, IRF4, IRF5, IRF7, and IRF9-that collectively shape inflammatory, metabolic, and cell-fate programs across hepatic cell populations. We further highlight emerging therapeutic strategies such as STING/TBK1 inhibition, NETosis blockade, IL-22-based epithelial repair, and JAK-STAT modulation that converge on IRF pathways. In summary, this review outlines how IRFs contribute to ALD pathogenesis and discusses the potential implications for the development of targeted therapies.

Myopathy, Lactic Acidosis, and Sideroblastic Anemia type 2 (MLASA2) is a rare mitochondrial disorder caused by pathogenic variants (PVs) in the YARS2 gene (which encodes the Mt-TyrRS protein. We performed a comprehensive clinical-molecular synthesis by integrating a systematic review and meta-analysis of all published MLASA2 cases with survival modeling and three-dimensional structural mapping. Across the aggregated cohort, anemia (88.6%), sideroblastic phenotype (85.7%), and lactic acidosis (82.9%) were the most prevalent phenotypes. Fifteen PVs were identified, dominated by p.(Phe52Leu) (29.4%). Survival estimates were 94.1% at 10 years, 70.7% at 30 years, and 42.4% at 50 years; cardiomyopathy and diagnosis before age 10 were associated with decreased survival. We generated the first 3D structural map of all reported Mt-TyrRS PVs, identifying nine spatial hotspots across catalytic, anticodon-binding, and tRNA-binding domains. An integrated framework combining structural density, clinical severity, in silico predictions, and ΔΔG destabilization classified three clusters as High-risk, three as Medium-risk, and three as Low-risk. Among them, cluster 3, a large catalytic hotspot encompassing 44 residues and including nearly half of all MLASA2 cases, showed the strongest pathogenic convergence. This clinical-structural integration provides new insights for a better comprehension of MLASA2, enhancing variant interpretation and improving diagnostic and prognostic precision.

Previous studies have shown that miR-5110 regulates pigmentation by cotargeting melanophilin (MLPH) and WNT family member 1 (WNT1). In order to find the possible molecular mechanism for pigmentation, we examined the mRNA expression profiles in melanocytes of alpaca transfected with miR-5110, inhibitor or negative control (NC) plasmids using high-throughput RNA sequencing. The results showed that a total of 91,976 unigenes were assembled from the reads, among which 13,262 had sequence sizes greater than 2000 nucleotides. According to the KEGG pathway analysis, four pathways related to melanogenesis, the MAPK signaling pathway, Wnt signaling pathway, and cAMP signaling pathway were identified. Compared to the NC, 162 gene were upregulated and 41 genes were downregulated in melanocytes over expressed by miR-5110. The differential expressions of mRNAs Dickkopf 3 (DKK3), premelanosome protein (Pmel), insulin-like growth factor 1 receptor (IGF1R), cyclin-dependent kinase 5 (CDK5), endothelin receptor type B (Ednrb), kit ligand (Kitl), Myc, and S100 were verified using qRT-PCR, which agreed with the results of RNA sequencing. We also verified the differential expressions of mRNAs of some genes in the MAPK signaling pathway using qRT-PCR, which agreed with the results of RNA sequencing. Interestingly, several genes were screened as candidates for the melanogenesis regulated by miR-5110, including Kitl and MAPK-activated protein kinase 3 (MAPKAPK3). These findings provide new insights for further molecular studies on the effects of miR-5110 on the melanogenesis and pigmentation.

Predicting neoadjuvant chemotherapy response in breast cancer remains critical for optimizing treatment strategies, yet robust predictive biomarkers are lacking. This study implemented an ensemble machine learning approach to identify a gene expression signature predicting pathological complete response (pCR) versus residual disease (RD) using bulk RNA-sequencing data from GSE163882 (138 RD, 80 pCR). We employed TMM normalization with differential expression analysis (250 genes, FDR < 0.05, |log2FC| ≥ 1), ensemble feature selection across five classifiers (Random Forest, Gradient Boosting, SVM, k-NN, and Neural Network) with 10-fold repeated cross-validation, and stacked ensemble development. Consensus selection identified a 17-gene signature consistently ranked across algorithms. The stacked ensemble achieved 0.97 AUC post-testing on hold-out test data. External validation on the independent GSE240671 cohort (37 pCR, 25 RD) following ComBat batch correction achieved ROC AUC of 0.78 and PR AUC of 0.85 with isotonic calibration, demonstrating balanced accuracy of 0.71 and 0.86 sensitivity for pCR detection. Pathway enrichment revealed associations with cell cycle regulation (E2F3, MKI67), DNA repair (BRCA2), and transcriptional control (MED1), with six priority genes (MED1, BRCA2, E2F3, PITPNB, H1-1, and FARP2) showing established breast cancer relevance. This externally validated 17-gene signature provides a biologically grounded tool for NAC response prediction in precision oncology.

Desmoplastic small round cell tumor (DSRCT) is a rare but aggressive soft tissue sarcoma of the abdomen. With an asymptomatic course and rapid dissemination, DSRCT's prognosis is poor at diagnosis. This study characterizes the demographic variation and genomic profile of DSRCT to guide studies into diagnosis and treatment. The AACR GENIE database was utilized to identify genetic alterations in DSRCT. Data was queried to identify disease prevalence by different demographic variables. Information was collected on frequency of somatic mutations and copy number alterations, rates of mutation co-occurrence, and mutations seen in primary and metastatic samples. ARID1A, TP53, ATM, TERT, and FGFR4 were the most frequently identified somatic mutations. Copy number alterations seen in DSRCT were commonly homozygous deletions in tumor suppressor genes. Independent of sex, WT1 mutations were most common. Non-White patients saw single occurrences of many mutations but recurrent ones in ANKRD11 and KMT2C. Co-occurrence was found between FGFR4 and EP300. Moreover, primary tumor samples had exclusive mutations in AKAP9, KDM2B, MAGED1, MKI67, PCLO, and TRAF1. Metastatic samples had exclusive mutations in FIP1L1 and NRIP1. Our data highlights mutational variation across demographic cohorts. These patterns are vital to future studies into identifying diagnostic markers or therapeutic targets.

Simultaneously inhibiting beta-amyloid protein (Aβ) aggregation and reducing metal ion overload in the brain is a promising strategy for treating Alzheimer's disease (AD). Aloe emodin (AE) is one of the major components of the traditional Chinese medicine rhubarb. Based on its reported pharmacological effects and its structural affinity for metal ions, this study aims to explore the potential of AE in improving AD pathology. Through the injection of Aβ or copper-Aβ complex in the bilateral hippocampus of rats, we constructed two kinds of nontransgenic animal models. Behavioral tests were used to evaluate cognitive impairment, and the effects of AE on neuronal damage and Aβ deposition were measured via Nissl staining and immunohistochemistry. Furthermore, we detected copper content in the serum and brain tissues as well as some biochemical indexes of Aβ cascade pathology in the brain tissues of model rats to explore the mechanism of action. AE treatment decreased copper accumulation and regulated Aβ metabolism in the brain of model rats, thereby improving Aβ deposition, memory impairment, hippocampal nerve cell damage, and related biochemical indicators. AE ameliorated the AD pathology of the model rats by targeting copper-induced Aβ toxicity, revealing a mechanism of action by which AE may exhibit good clinical efficacy in treating AD.

Tauroursodeoxycholic acid (TUDCA), a bile acid conjugate, has been suggested to improve cognition in models of Alzheimer's disease (AD), although its underlying mechanisms remain unclear. This study aimed to evaluate the effects of TUDCA and its potential pathways in APP/PS1 mice. Behavioral tests, assessments of amyloid-β (Aβ) deposition, neuroinflammation, peripheral inflammatory responses, intestinal barrier integrity, and gut microbiota composition were performed, along with pseudo-sterile mouse experiments and fecal microbiota transplantation (FMT). The expression of genes related to the TLR4/NF-κB/NLRP3 pathway was also examined. TUDCA significantly ameliorated cognitive impairments, reduced Aβ accumulation, and suppressed inflammatory responses in both the central nervous system and peripheral tissues. It improved intestinal barrier function and reshaped gut microbial composition by reducing pro-inflammatory taxa. FMT demonstrated that TUDCA-modulated microbiota contributed to improved learning and memory in AD mice, whereas antibiotic-induced pseudo-sterility indicated that TUDCA also exerted cognitive benefits independent of gut flora. Moreover, TUDCA inhibited the activation of the TLR4/NF-κB/NLRP3 pathway. In conclusion, TUDCA alleviates AD-related cognitive deficits partly through modulation of the microbiota-gut-brain axis while also acting via microbiota-independent mechanisms, supporting its potential as a promising therapeutic strategy for AD.

Neuronal synapses are the functional units of communication in the central nervous system. This review describes the molecular mechanisms regulating synaptic transmission, plasticity, and circuit refinement. At the presynaptic active zone, scaffolding proteins including bassoon, piccolo, RIMs, and munc13 organize vesicle priming and the localization of voltage-gated calcium channels. Neurotransmitter release is mediated by the SNARE complex, comprising syntaxin-1, SNAP25, and synaptobrevin, and triggered by the calcium sensor synaptotagmin-1. Following exocytosis, synaptic vesicles are recovered through clathrin-mediated, ultrafast, bulk, or kiss-and-run endocytic pathways. Postsynaptically, the postsynaptic density (PSD) serves as a protein hub where scaffolds such as PSD-95, shank, homer, and gephyrin anchor excitatory (AMPA, NMDA) and inhibitory (GABA-A, Glycine) receptors are observed. Synaptic strength is modified during long-term potentiation (LTP) and depression (LTD) through signaling cascades involving kinases like CaMKII, PKA, and PKC, or phosphatases such as PP1 and calcineurin. These pathways regulate receptor trafficking, Arc-mediated endocytosis, and actin-dependent remodeling of dendritic spines. Additionally, synapse formation and elimination are guided by cell adhesion molecules, including neurexins and neuroligins, and by microglial pruning via the complement cascade (C1q, C3) and "don't eat me" signals like CD47. Molecular diversity is further expanded by alternative splicing and post-translational modifications. A unified model of synaptic homeostasis is required to understand the basis of neuropsychiatric and neurological disorders.