Biomolecules最新文献

Recurrent endometrial cancer (EC) has limited therapeutic options beyond platinum-based chemotherapy, highlighting the need to identify exploitable molecular vulnerabilities. Tumors with high genomic instability, including microsatellite instability-high (MSI-h) or copy-number-high (CNH) ECs, rely on the ATR-CHK1 signaling pathway to tolerate replication stress and maintain genome integrity, making this pathway an attractive therapeutic target. However, acquired resistance to ATR and CHK1 inhibitors (ATRi/CHK1i) often develops, and the transcriptomic basis of this resistance in EC remains unknown. Here, we established isogenic ATRi- and CHK1i-resistant cell line models from MSI-h (HEC1A) and CNH (ARK2) EC lineages and performed baseline transcriptomic profiling to characterize stable resistance-associated states. MSI-h-derived resistant clones adopted a unified transcriptional state enriched for epithelial-mesenchymal transition, cytokine signaling, and interferon responses, while ATRi-resistant models showing additional enrichment of developmental and KRAS/Notch-associated pathways. In contrast, CNH-derived resistant clones diverged by inhibitor class, with ATRi resistance preferentially enriching proliferation-associated pathways and CHK1i resistance inducing interferon signaling. Notably, THBS1, EDN1, and TENM2 were consistently upregulated across all resistant models relative to parental lines. Together, these findings demonstrate that acquired resistance to ATRi and CHK1i in EC is shaped by both lineage and inhibitor class and provide a transcriptomic framework that may inform future biomarker development and therapeutic strategies.

The intervertebral disc (IVD) is the largest avascular structure in the human body, and its nucleus pulposus (NP) cells predominantly generate large amounts of lactate through glycolysis, accompanied by an acidic microenvironment-features that represent characteristic metabolic traits of disc cells. In recent years, knowledge of the biological roles of lactate has undergone a conceptual shift. On the one hand, lactate can serve as a context-dependent auxiliary biofuel in specific regions of the IVD, particularly within annulus fibrosus (AF) regions adjacent to the NP. On the other hand, lactate functions in disc cells as a signaling molecule and a metabolic-epigenetic regulator, influencing transcriptional programs through lactylation and modulating multiple molecular pathways associated with cellular stress adaptation and fate determination. This review summarizes current knowledge on lactate production, transport, and clearance in the intervertebral disc, as well as emerging evidence for the roles of lactate in disc health and pathophysiology. In addition, we outline research perspectives and future directions aimed at advancing our understanding of lactate biology and evaluating its potential as a therapeutic target for intervertebral disc degeneration.

Background: Survivin is an anti-apoptotic protein highly expressed during embryonic development and, in adults, mainly in the gastrointestinal epithelium. Its levels decrease in human gastric tissue and cultured cells upon exposure to Helicobacter pylori gamma-glutamyl transpeptidase (GGT), though the underlying mechanism remains unclear.

Objective: We aimed to investigate the role of cap-independent translation driven by the Survivin 5' untranslated region (5'UTR) in response to H. pylori infection in vitro.

Methodology: Human cell lines (AGS, GES-1, HeLa, HEK293T) were used alongside bicistronic and monocistronic (Firefly/Renilla luciferases) reporter assays to assess short and long variants of the Survivin 5'UTR and HIV-1 internal ribosome entry site (IRES) sequences. Additional methods included in vitro transcription/translation, RT-qPCR, agarose gel electrophoresis, Western blotting, coupled/uncoupled translation assays, and siRNA silencing.

Results: The short variant of the Survivin 5' UTR supported cap-independent translation, like the HIV-1 IRES. Notably, H. pylori infection suppressed this translation in a GGT-dependent manner in gastric cells, and a similar reduction was observed following treatment with ATO, a known prooxidant.

Conclusion: The Survivin 5'UTR exhibits cap-independent translation activity that is inhibited by H. pylori in a GGT-dependent manner, likely via oxidative stress. This mechanism helps to explain the downregulation of Survivin during gastric infection and indicates that oxidative stress can negatively affect both cellular and viral IRES-mediated translation.

PARP inhibitors are a clinically validated class of anticancer therapeutics that exploit synthetic lethality to target homologous recombination-deficient tumors, such as those carrying BRCA1/2 mutations. Nevertheless, the rational design of mitochondria-targeted PARP inhibitors capable of selective mitochondrial accumulation and organelle-specific PARP modulation remains an unresolved objective. To enable organelle-specific modulation of PARP activity, we synthesized a series of trialkyl(aryl)phosphonium conjugates of olaparib and rucaparib designed to target mitochondria by cardiolipin binding. Their activity was evaluated by PARP1 inhibition, cardiolipin affinity, and cytotoxicity in BRCA1-deficient HCC1937 breast cancer cells and non-malignant H9C2 cardiomyocytes. All conjugates retained potent PARP1 inhibition (IC₅₀ = 3.4-17 nM), comparable to the parent drugs. Several derivatives, particularly compounds 2d and 6c, exhibited strong cardiolipin binding (EC₅₀ = 12.99 µM and 6.77 µM, respectively) and significantly enhanced cytotoxicity in HCC1937 cells (IC₅₀ = 0.93 and 2.01 µM), outperforming olaparib and rucaparib. Notably, cytotoxicity toward H9C2 cells was lower, indicating a favorable selectivity profile. Phosphonium conjugation preserves PARP1 inhibitory activity while conferring mitochondrial targeting and enhanced anticancer potency. These findings support the development of mitochondria-targeted PARP inhibitors as a next-generation therapeutic strategy with the potential to improve efficacy and overcome resistance in HR-deficient tumors.

Initially characterized as a component of the extracellular matrix (ECM) in cartilage, cartilage intermediate layer protein 2 (CILP2) is now recognized as a pleiotropic secretory protein with far-reaching roles in physiology and disease. This review synthesizes evidence establishing CILP2 as a key modulator at the nexus of metabolic dysfunction, cancer, and other pathologies. Genomic studies have firmly established the NCAN-CILP2 locus as a hotspot for genetic variants influencing dyslipidemia and cardiovascular risk. Functionally, CILP2 is upregulated by metabolic stress, including high glucose and oxidatively modified LDL (oxLDL), and actively contributes to pathologies such as dyslipidemia, diabetes, and sarcopenia by impairing glucose metabolism and mitochondrial function. Its role extends to fibrosis and neurodevelopment, promoting hypertrophic scar formation and neurogenesis through interactions with ATP citrate lyase (ACLY) and Wnt3a, respectively. More recently, CILP2 has emerged as an oncoprotein, overexpressed in multiple cancers, including pancreatic ductal adenocarcinoma and colorectal cancer. It drives tumor proliferation and metastasis and correlates with tumor microenvironment remodeling through mechanisms involving Akt/EMT signaling and immune infiltration. The dysregulation of CILP2 in patient serum and its correlation with disease severity and poor prognosis highlight it as a promising biomarker and a compelling therapeutic target across a spectrum of human diseases.

Endometriosis is an inflammatory estrogen-dependent disorder characterized by pain, dyspareunia, dysmenorrhea, and infertility. This is due to the invasion of different organs by endometrial tissue that causes inflammation, angiogenesis, and fibrosis. The ion channels Piezo1 and Piezo2 primarily work as mechanosensors and mechanotransducers but also have functions that could participate in the clinical hallmarks of endometriosis. Thus, we investigated the occurrence and localization of Piezo1 and Piezo2 in healthy human endometrium and in endometriosis using immunohistochemistry. In healthy endometrium, Piezo1 immunoreactivity was detected in the glands and to a lesser extent in the stroma; Piezo2 was present in the same locations but at low or residual levels. In ectopic endometriosis, there was an increase in the intensity of Piezo1 regardless of location; Piezo2 only showed a net increase in the ovarian and vaginal endometriosis foci. The present results demonstrate the occurrence of Piezo ion channels in the healthy human endometrium for the first time, as well as an increase in Piezo1 in ectopic endometriosis, and no changes in Piezo2 with the exception of the ovary and vagina. However, these results are descriptive and qualitative, although they may serve as the basis for further studies. The role of these ion channels in the endometrium and in the pathogenesis of endometriosis remains to be elucidated, and more precise methods are needed to follow up on this pilot study that can be better analyzed statistically to confirm the results.

SARS-CoV-2, the virus responsible for coronavirus disease COVID-19, is a highly transmissible pathogen that has caused substantial global morbidity and mortality. The ongoing COVID-19 pandemic caused by this virus has had a significant impact on public health and the global economy. One approach to combating COVID-19 is the development of broadly neutralizing antibodies for prevention and treatment. In this work, we performed an in silico ligand-based screening of the PDB database to search for unique anti-SARS-CoV-2 motifs. The collected data were organized and presented in a classified SARS-CoV-2 Ligands Database, categorized based on the number of ligands and structural components of the spike glycoprotein. The database contains 1797 entries related to the structures of the spike glycoprotein (UniProt ID: P0DTC2), including both full-length molecules and their fragments (individual domains and their combinations) with various ligands, such as angiotensin-converting enzyme II and antibodies. The database's capabilities allow users to explore various datasets according to the research objectives. To search for motifs in the receptor-binding domain (RBD) most frequently involved in antibody binding sites, antibodies were classified into four classes according to their location on the RBD; for each class, special binding motifs are revealed. In the RBD binding sites, specific tyrosine-containing motifs were found. Data obtained may help speed up the creation of new antibody-based therapies, and guide the rational design of next-generation vaccines.

Lipoxygenases are enzymes found in plants, mammals, and other organisms that catalyse the hydroperoxidation of polyunsaturated fatty acids, such as arachidonic, linoleic, and linolenic acids. They have attracted a lot of attention as molecular targets for industrial and biomedical applications, due to their implication in key biological processes, such as plant development and defence, cell growth, as well as immune response and inflammation. Soybean (Glycine max) lipoxygenase (LOX) is a versatile biocatalyst used in biotechnology, pharmaceutical, and food industries. sLOX1, a soybean LOX isoform, is central in various industrial applications; thus, it is of particular interest to develop an efficient sLOX1 isolation process, control its activity, and leverage its potential as an effective industrial biocatalyst, tailoring it to a specific desired outcome. In this study, sLOX1 was extracted and purified from soybean seeds using an optimized protocol that yielded an enzyme preparation with higher activity compared to the commercially available lipoxygenase. Comprehensive biophysical characterization employing dynamic and electrophoretic light scattering, fluorescence, and Fourier-transform infrared spectroscopies revealed that sLOX1 exhibits remarkable structural and functional stability, particularly in sodium borate buffer (pH 9), where it retains activity and integrity up to at least 55 °C and displays minimal aggregation under thermal, ionic, and temporal stress. In contrast, sLOX1 in sodium phosphate buffer (pH 6.8) remained relatively stable against ionic strength and time but showed thermally induced aggregation above 55 °C, while in sodium acetate buffer (pH 4.6), the enzyme exhibited a pronounced aggregation tendency under all tested conditions. Overall, this study provides physicochemical and stability assessments of sLOX1. The combination of enhanced catalytic activity, high purity, and well-defined stability profile across diverse buffer systems highlights sLOX1 as a promising and adaptable biocatalyst for industrial applications, offering valuable insights into optimizing lipoxygenase-based bioprocesses.

Low social status leads to chronic social stress that predicts risk for physical and mental illness, especially when it starts early in life. To examine the longitudinal effects of low social status on the immune system, this study assessed the effects of low social status on developmental secretory patterns of pro- and anti-inflammatory markers under baseline conditions, as well as in response to an immune challenge (lipopolysaccharide (LPS)-induced activation of pro- and anti-inflammatory cytokines) in a translational rhesus monkey model of lifelong social subordination stress. Baseline blood samples were collected in 27 socially housed female rhesus monkeys (13 dominants, DOM, and 14 subordinates, SUB) during infancy (6 months), the juvenile pre-pubertal period (16 months), and adulthood (9-10 years) to examine the longitudinal effects of social status on inflammatory markers in unstimulated versus LPS-stimulated conditions mimicking exposure to bacterial infection. Basal levels of the stress hormone cortisol in blood were measured to examine associations between inflammation and activity of the hypothalamic-pituitary-adrenal (HPA) axis throughout the life span. Basal peripheral levels of inflammatory markers (e.g., IL-6) increased across development in both SUB and DOM animals with no significant differences. Basal cortisol levels were significantly higher in infancy as compared to adulthood, but no significant effects of social rank were detected. However, in adulthood, SUB animals showed a cytokine-specific immune response to ex vivo LPS stimulation with significantly higher secretions of IL-1β, IL-2, and IL-10 compared to DOM animals, whereas IL-8 response to LPS was lower in SUB animals than in DOMs. This cytokine-specific response to an immune challenge that mimics bacterial infection could reflect dysregulated immune cells that may have short-term adaptation, but at the cost of longer-term risks for low-grade chronic inflammation and accelerated immune aging for socially subordinate female macaques.

Immunotherapy, especially immune checkpoint inhibitors (ICIs), has become one of the core therapeutic approaches in cancer in recent years. It demonstrates remarkable efficacy in the treatment of melanoma and lung cancer. Conversely, its use in treating gastric cancer (GC) is not associated with considerable benefits. The high heterogeneity of GC and the tumor microenvironment (TME) may directly influence this phenomenon. This review focuses on the correlation between Helicobacter pylori (H. pylori) infection, gastric physiology, and molecular subtype-specific induction pathways, with emphasis on the unique metabolic features of GC. It explores the connection of H. pylori infection, gastric physiologic functions, and molecular subtype-specific induction mechanism of GC with the special metabolism of GC. It also explains the relationship between immune metabolic reprogramming and the suppressive TME in GC. Crucially, we summarize emerging therapeutic strategies targeting metabolic vulnerabilities. Furthermore, we explore the potential of subtype-guided metabolic therapies to overcome the challenges of the immunosuppressive tumor microenvironment in GC.