Search Results (149)

Cisplatin [cis-diamminedichloroplatinum(II)] is a widely used chemotherapeutic agent that induces cytotoxicity primarily through DNA damage; however, drug resistance severely limits its efficacy. Cisplatin resistance is complex and multifactorial, involving DNA repair via nucleotide excision repair (NER), increased detoxification activities, and overexpression of lysine deacetylases (KDACs), which reduce chromatin accessibility and alter transcriptional regulation. Combining cisplatin with KDAC inhibitors has shown promise, often attributed to increased drug sensitivity through higher chromatin accessibility; however, this hypothesis has not been validated. Here, we synthesized a novel Pt(IV) derivative, ctc-[Pt(NH₃)₂(VPA)(PhB)Cl₂] (cPVP), which combines cisplatin with two KDAC inhibitors, phenylbutyrate and valproic acid. Compared with cisplatin, cPVP induced significantly greater cytotoxicity, and increased DNA damage formation. High-resolution mapping of genomic cisplatin damage and repair indicated that enhanced sensitivity resulted not from altered chromatin accessibility, but from increased drug uptake and the inhibition of NER. Moreover, cPVP prevented the development of resistance to both cisplatin and itself in cancer cells. Together, these results establish the inhibition of nucleotide excision repair, rather than enhanced damage sensitivity due to chromatin accessibility, as the primary mechanism by which KDAC-targeting cisplatin prodrugs overcome resistance to platinum-based therapies. Full article

Evaluating cancer gene mutations is critical for effective therapeutic selection. Although massive parallel sequencing can efficiently detect gene mutations, most are variants of uncertain significance (VUS). Saturation genome editing (SGE) can facilitate VUS analysis by leveraging CRISPR-Cas9 and homology-directed repair to simultaneously introduce abundant gene mutations. Chronic myelogenous leukemia-derived HAP1 cells are widely used in SGE because of their clear genotype–phenotype relationship; however, the sole use of haploid cells limits SGE applicability in cancer research. Therefore, we developed an SGE-based system for evaluating KRAS mutations in diploid HCT 116 colon carcinoma cells. Single-nucleotide variants (SNVs) in KRAS codons A11–V14 were generated using Cas9-based SGE. Massive parallel sequencing revealed increased abundance of KRAS ^G12 and KRAS ^G13 SNVs and decreased abundance of the KRAS ^G12C SNV after KRAS ^G12C inhibitor treatment in SGE pooled cells. These results indicate that SGE is applicable to diploid HCT 116 cells and useful for evaluating SNV population changes and drug sensitivity. Thus, although haploid HAP1 cells are the primary models for SGE, the successful application of SGE to diploid HCT 116 colon carcinoma cells provides a practical framework for implementing SGE in KRAS-dependent carcinoma cells. Full article

A point-of-care (POC) HIV drug resistance (HIV-DR) test is needed for low- and middle-income countries (LMICs). Oligonucleotide Ligation Assay (OLA)-Simple, designed as a near-POC HIV-DR test, was assessed for its overall usability in Kenya by technicians with and without molecular laboratory PCR experience. Further, its diagnostic accuracy was evaluated by PCR-experienced technicians utilizing 147 plasma samples with known Sanger sequence genotypes—based on seven major HIV-DR mutations of nucleotide and non-nucleoside reverse transcriptase inhibitors. Thirteen laboratory technicians were recruited, including five with prior PCR experience. Twelve technicians completed the training and attained OLA-Simple testing competency, ten of whom were able to perform the OLA-Simple test within 6 h. Technicians’ survey feedback indicated the user-friendliness of OLA-Simple, citing straightforward reagent reconstitution, concise instructions in prompts, and a shorter sample-to-result test time compared to standard genotyping assays. Of the 147 archived plasma samples tested, 132 (90%) yielded interpretable results. OLA-Simple assay demonstrated a sensitivity of 97.3% (95% CI 94.5, 98.9), a specificity of 97.2% (95% CI 95.5, 98.3), and a percent agreement of 97.1% (95% CI 95.9, 98.2) compared to Sanger sequencing. This evaluation found that OLA-Simple was user-friendly among intended end-users and performed well. LMIC HIV programs would benefit from strategizing on case-use scenarios for such near-POC HIV-DR assays to improve HIV outcomes. Full article

The use of antiretroviral therapy (ART) as the only effective way to control human immunodeficiency virus (HIV) infection results in HIV drug resistance. Next-generation sequencing (NGS) has become a common method for identifying drug-resistant variants and reducing analysis costs. The aim of this study was to develop an NGS-based protocol for identifying resistance mutations and cell tropism of HIV-1 in adult patients with and without treatment experience in Russia in 2024–2025. Plasma samples from adult HIV-infected patients from Russia were analyzed. Consensus nucleotide sequences of pol and env genes were obtained using NGS. HIV-1 drug resistance analysis was conducted using the Stanford University HIVdb database. CXCR4 cell tropism was predicted using an empirical rule classifier. A protocol for NGS of HIV-1 pol and env genes was developed. The most common HIV-1 surveillance mutations were in the reverse transcriptase. High levels of resistance were observed to non-nucleoside reverse transcriptase inhibitors (NNRTIs) and nucleoside reverse transcriptase inhibitors (NRTIs) in treatment-experienced patients and to NNRTIs in treatment-naïve patients. Low levels of resistance were observed to protease and integrase strand transfer inhibitors (INSTIs). CXCR4 cell tropism was extremely rare. NGS allows for the simultaneous processing of large data sets during epidemiological studies. The introduction of NGS-based protocols allows for performing ART efficiency and tropism monitoring at scale. Full article

The genetic basis for Tibetan sheep adaptation to different high-altitude environments remains unknown. This study conducted whole-genome resequencing on 80 Tibetan sheep individuals from four major distribution areas on the Qinghai–Tibet Plateau. Based on the high-quality single-nucleotide polymorphisms (SNPs) obtained, an analysis of population-level genomic selection signals was performed. Population genomic analysis revealed that Tibetan sheep distributed across China originated in northern China but showed evidence of gene flow from South Asian sheep. Between populations from extremely high-altitude and mid-altitude regions, selection analyses identified five strongly positive selected genes (HIF1AN [Hypoxia Inducible Factor 1 Alpha Subunit Inhibitor], HBE1 [Hemoglobin Subunit Epsilon 1], HBE2 [Hemoglobin Subunit Epsilon 2], TNFAIP3 [TNF Alpha Induced Protein 3], RAD50 [RAD50 Double Strand Break Repair Protein]). These genes are associated with adaptation to hypoxia and intense UV radiation in high-altitude environments. Selection analyses between populations from extremely high-altitude and mid-altitude regions identified five strongly selected genes (HIF1AN [Hypoxia Inducible Factor 1 Alpha Subunit Inhibitor], HBE1 [Hemoglobin Subunit Epsilon 1], HBE2 [Hemoglobin Subunit Epsilon 2], TNFAIP3 [TNF Alpha Induced Protein 3], RAD50 [RAD50 Double Strand Break Repair Protein]) associated with hypoxia and intense UV radiation in high-altitude environments. Comparative genomic analyses of populations in cold and arid environments identified several candidate genes related to energy and water homeostasis, as well as hair development (TP53 [Tumor Protein P53], ATG101 [Autophagy Related 101], ATP12A [ATPase H+/K+ Transporting Non-Gastric Alpha2 Subunit], KRT80 [Keratin 80], KRT7 [Keratin 7]). Additionally, Tibetan sheep in the high-altitude arid deserts exhibit stronger adaptive selection for energy homeostasis and water utilization; meanwhile, the HIF-1 [Hypoxia Inducible Factor 1] signaling pathway helps counteract oxidative stress induced by extreme water scarcity in the plateau environment. Our study supports the hypothesis that Tibetan sheep originated in northern China and identifies distinct adaptive features in the Tibetan sheep genome corresponding to their habitats. Full article

Thrips are cosmopolitan agricultural pests and important vectors of plant viruses, and the increasing coexistence of multiple morphologically similar species has intensified the demand for species-specific molecular identification. However, traditional morphological identification and PCR assays using universal primers are often inadequate for mixed-species samples and field-adaptable application. In this study, we developed a species-specific molecular identification framework targeting a polymorphism-rich region of the mitochondrial cytochrome c oxidase subunit I (COI) gene, which is more time-efficient than sequencing-based COI DNA barcoding, for four economically important thrips species in southern China, including the globally invasive Frankliniella occidentalis. By aligning COI sequences, polymorphism-rich regions were identified and used to design four species-specific primer pairs, each containing a diagnostic 3′-terminal nucleotide. These primers were combined with a PBS-based DNA extraction workflow optimized for single-insect samples that minimizes dependence on column-based purification. The assay achieved a practical detection limit of 1 ng per reaction, demonstrated species-specific amplification, and maintained reproducible amplification at DNA inputs of ≥1 ng per reaction. Notably, PCR inhibition caused by crude extracts was effectively alleviated by fivefold dilution. Although the chemical identities of the inhibitors remain unknown, interspecific variation in inhibition strength was observed, with T. hawaiiensis exhibiting the strongest suppression, possibly due to differences in lysate composition. This integrated framework balances target specificity, operational simplicity, and dilution-mitigated inhibition, providing a field-adaptable tool for thrips species identification and invasive species monitoring. Moreover, it provides a species-specific molecular foundation for downstream integration with visual nucleic acid detection platforms, such as the CRISPR/Cas12a system, thereby facilitating the future development of portable molecular identification workflows for small agricultural pests. Full article

Nucleoside analogs remain central to the treatment of hematologic malignancies and solid tumors, yet resistance frequently occurs, contributing to relapse and disease-related mortality. Rather than arising from a single mechanism, effective nucleoside analog activity requires successful navigation of multiple biological barriers, including cellular uptake, intracellular activation, nucleotide pool balance, genome surveillance, and mitochondrial stress responses. This review integrates recent advances describing how alterations at each of these levels contribute to resistance to nucleoside analog therapies. We further highlight emerging therapeutic strategies centered on small-molecule inhibitors that exploit these vulnerabilities to enhance the efficacy of nucleoside analogs. Together, this integrative perspective supports the need for development of small molecule inhibitors and design of combination approaches aimed at restoring apoptotic competence and improving the use of nucleoside analog-based therapies for the treatment of cancer. Full article

In this study, three point mutations of EGFR relevant to lung cancer therapy are detected. Mutated EGFR is the target of a therapy for non-small cell lung cancer (NSCLC) using tyrosine kinase inhibitors (TKIs) as treatment drugs. Background/Objectives: Point mutations in exon 21 (L858R and L861Q) of the EGFR gene are TKI-sensitive; however, mutations in exon 20 (T790M) are TKI-resistant. Therefore, a fast detection method that classifies an NSCLC patient to be drug sensitive or drug resistant is highly clinically relevant. Methods: Probes were designed to detect three point mutations in genomic samples based on DNA hybridization on a solid surface. A method has been developed to detect single nucleotide polymorphism (SNP) for these mutation detections in the 16-channel nanobioarray chip. The wash by gold-nanoparticles (AuNP) was used to assist the differentiation detection. Results: The gold nanoparticle-assisted wash method has enhanced differentiation between WT and mutated sequences relevant to the EGFR sensitivity to tyrosine kinase inhibitors. Conclusions: The WT and mutated sequences (T790M, L858R and L861Q) in genomic samples were successfully differentiated from each other. Full article

(1) Background: All-trans retinoic acid (ATRA) has transformed the treatment of acute promyelocytic leukemia (APL) by inducing terminal myeloid differentiation. However, its efficacy in non-APL acute myeloid leukemia (AML) is limited. Exploring combination strategies that enhance ATRA-induced differentiation may broaden its therapeutic potential. (2) Methods: A literature search of PubMed using the keywords “ATRA,” “myeloid,” and “differentiation inducer or enhancer” identified more than 500 published papers as of November 2025. Pre-clinical and clinical studies were reviewed, with a focus on mechanisms, combination partners, and translational relevance. (3) Results: Clinical evidence confirms that ATRA combined with arsenic trioxide or epigenetic modulators achieves high remission rates in APL and selected AML subtypes. Pre-clinical studies show synergistic differentiation effects when ATRA is combined with CDK and kinase inhibitors, nucleotide synthesis inhibitors, DNA-damaging agents, Bcl-2/MDM2 inhibitors, proteasome inhibitors, cytokines, glycosylation modifiers, natural products, and antibiotic-derived compounds. Mechanistically, these combinations modulate key signaling pathways (MAPK, Akt, JAK/STAT), stabilize RARα, remodel chromatin, and perturb nucleotide metabolism. Although translation to non-APL AML remains limited, these findings provide a rational basis for future clinical trials. (4) ATRA-based combination therapies represent a promising strategy to extend differentiation therapy beyond APL. This review, authored solely by the investigator, highlights molecular targets and potential enhancers warranting further clinical evaluation in AML. Full article

In the pathological process of acute kidney injury (AKI) and its transition to chronic kidney disease, the uric acid (UA) metabolic pathway plays a significant role. UA is produced as the last oxidative product in the metabolism of purine nucleotides. Prolonged organ ischemia promotes the breakdown of nucleotides into adenosine, hypoxanthine, xanthine, and UA. In this study, animal models of ischemia–reperfusion-induced AKI and renal tubular epithelial cells subjected to hypoxia–reoxygenation injury exhibited significantly reduced ATP levels, along with elevated concentrations of purine catabolites, including AMP, hypoxanthine, xanthine, and UA. Concurrently, the expression of xanthine oxidase (XO), a key enzyme in purine catabolism, was upregulated, peaking at 3 h after reoxygenation, accompanied by increased reactive oxygen species (ROS) production. Treatment with the XO inhibitor febuxostat in hypoxia–reoxygenated HK-2 cells led to a marked reduction in UA, inflammatory cytokines, and ROS levels, along with decreased apoptosis and enhanced proliferative capacity. Clinical data analysis revealed that 59.4% of AKI patients presented with hyperuricemia. UA levels demonstrated a linear correlation with the estimated glomerular filtration rate (eGFR) and the tissue necrosis marker lactate dehydrogenase (LDH). A random forest model constructed based on UA, LDH, age, diabetes, and hypertension accurately predicted the eGFR. These findings indicate that patients with I/R-induced AKI exhibit enhanced purine catabolism, and purine metabolic breakdown products are closely associated with the severity of renal injury in I/R AKI. For high-risk AKI populations or patients diagnosed with AKI with significantly elevated UA levels, febuxostat may be considered to prevent AKI onset and improve renal function. Furthermore, in AKI patients where creatinine data are unavailable or not significantly elevated despite markedly increased UA levels, a comprehensive assessment incorporating relevant indicators of glomerular filtration function is recommended. Full article

Triple-negative breast cancer (TNBC) is an aggressive subtype characterized by a lack of targetable receptors, leading to limited treatment options and a critical need for novel therapeutic strategies. This study aimed to evaluate the potential of azelastine, a clinically approved H1-antihistamine, for drug repositioning against TNBC and to elucidate its underlying HRH1-independent mechanism of action. Cell viability assays (CCK-8) were performed on TNBC cell lines (MDA-MB-231 and BT-549) following treatment with azelastine and its major metabolite, desmethyl azelastine. After observing ambiguous clinical associations between HRH1 expression and patient prognosis, HRH1 dependency was assessed through histamine stimulation and HRH1 knockdown (siRNA). Subsequently, the role of ADP-ribosylation factor 1 (ARF1), found to be overexpressed in TNBC and linked to poor prognosis, was investigated using ARF1 knockdown (siRNA), co-treatment with the Golgi-specific brefeldin A-resistance guanine nucleotide exchange factor 1 (GBF1) inhibitor golgicide A (GCA), and co-treatment with the Drp1 inhibitor M-divi 1. Azelastine and desmethyl azelastine potently reduced MDA-MB-231 cell viability in a dose- and time-dependent manner, achieving cell survivals of 61.3 ± 6.1% (30 µM) and 34.9 ± 3.7% (50 µM) for azelastine, and 52.4 ± 12.5% (30 µM) for desmethyl azelastine, respectively, after 72 h, with an IC₅₀ of 35.93 µM determined for azelastine in MDA-MB-231 cells. Additionally, azelastine significantly reduced the viability of BT-549 cells. Bioinformatic analysis of clinical datasets revealed HRH1 downregulation in tumors and, functionally, neither histamine stimulation nor HRH1 knockdown mediated azelastine cytotoxicity in cell culture. Importantly, ARF1 expression was significantly upregulated in TNBC and associated with poor prognosis. Co-treatment with GCA, preventing ARF1 activation, restored viability to near-control levels, supporting dependence on the GBF1–ARF1 activation axis of azelastine, whereas the Dynamic-related protein 1 (Drp1) inhibitor M-divi 1 not only partially rescued CCK-8-based cell viability but also normalized azelastine-induced loss of MitoTracker™ Red CMXRos signal and partially preserved (4′,6-diamidino-2-phenylindole) DAPI-based cell density, indicating Drp1-dependent mitochondrial dysfunction. Furthermore, azelastine selectively reduced p-ERK phosphorylation in the cell signaling pathway. Azelastine exerts potent anticancer effects in TNBC cells via an HRH1-independent, ARF1-dependent mechanism that attenuates the Extracellular signal-regulated kinase (ERK)–Drp1 axis, and induces Drp1-dependent mitochondrial dysfunction, independent of its canonical HRH1 receptor function. This ARF1-dependent mechanism provides strong scientific rationale for the drug repositioning of azelastine as an effective therapeutic agent for ARF1-driven TNBC. Full article

Ferroptosis is an iron-dependent form of regulated cell death driven by lipid peroxidation. Since the identification of dihydroorotate dehydrogenase (DHODH) as a mitochondrial suppressor of ferroptosis in 2021, increasing evidence has highlighted its role in linking nucleotide metabolism, redox regulation, and tumor progression. We conducted a comprehensive review of publications on DHODH, ferroptosis, and cancer. Relevant studies were analyzed to synthesize mechanistic insights, translational implications, and therapeutic perspectives. DHODH, a flavin-dependent mitochondrial enzyme catalyzing the oxidation of dihydroorotate to orotate, integrates pyrimidine biosynthesis with electron transport chain activity. Beyond its canonical metabolic role, DHODH regenerates ubiquinol (CoQ₁₀H₂) to suppress mitochondrial lipid peroxidation and ferroptosis. Elevated DHODH expression in colorectal, hepatocellular, breast, renal, and brain cancers correlates with poor prognosis, therapy resistance, and immune evasion. Pharmacological inhibition of DHODH disrupts pyrimidine synthesis and redox defense, sensitizing GPX4-low tumors to ferroptosis. Preclinical studies demonstrate synergy between DHODH inhibitors and chemotherapy, radiotherapy, or immune checkpoint blockade. Nanoparticle-based delivery systems enhance therapeutic efficacy by simultaneously targeting multiple ferroptosis defense arms while reducing toxicity. DHODH serves as both a metabolic and redox checkpoint in cancer, linking ferroptosis suppression to proliferation and immune escape. Targeting DHODH offers a promising strategy to dismantle cancer resilience, particularly in combination with ferroptosis inducers and immunotherapies. Future research should focus on biomarker-guided stratification, nanomedicine platforms, and clinical translation of DHODH inhibitors. Full article

Background/Objectives: The advent of biologics targeting key inflammatory pathways has significantly advanced psoriasis treatment. Among them, the Interleukin-23 inhibitors Guselkumab and Risankizumab have demonstrated high efficacy and rapid clinical response in both clinical trials and real-world studies. However, up to 30% of patients fail to respond. This study aimed to identify pharmacogenetic markers associated with treatment response using a genome-wide association study (GWAS) and protein network-based approach. Methods: Fifty-three patients of Greek origin with moderate-to-severe plaque psoriasis were treated with Guselkumab or Risankizumab. Based on Psoriasis Area and Severity Index (PASI) improvement at 3 and 6 months, patients were categorized as responders or non-responders. Approximately 730,000 single-nucleotide polymorphisms (SNPs) were genotyped. After filtering, a GWAS was performed to identify variants associated with treatment response. Additionally, protein–protein interaction (PPI) network analysis was applied to the two Interleukin-23 subunits and SNPs within or near genes encoding Interleukin-23-interacting proteins to test for their association. Results: The GWAS identified two novel variants, rs73641950 and rs6627462, significantly associated with treatment response, with both surpassing the genome-wide significance threshold after Bonferroni correction. The PPI-based approach revealed rs13086445, located downstream of the Interleukin-12 subunit alpha (IL12A) gene, as another associated variant. All three SNPs lie in genomic regions with potential regulatory roles. Conclusions: This study identifies three novel genetic variants associated with response to Interleukin-23 inhibitors in psoriasis. These findings provide promising pharmacogenetic markers which, upon validation in larger, independent cohorts, will enable the translation of a patient’s genotype into a response phenotype, thereby guiding clinical decisions and improving drug effectiveness. Full article

Background: Pharmacogenomics offers critical insights into interindividual variability in drug response, especially in complex diseases such as diabetes mellitus. However, most pharmacogenomic evidence is derived from populations of European ancestry, limiting its applicability in admixed and underrepresented populations. In Colombia, the lack of population-specific data hampers the implementation of precision medicine strategies in diabetes care. The aim of this study was to identify pharmacogenomic variants significantly associated with diabetes and exhibiting differential allele frequencies between Colombian populations of African and European ancestry. Methods: We extracted 115 variant annotations related to diabetes from PharmGKB and filtered them for statistical significance and availability of allele frequency data. Fourteen single-nucleotide polymorphisms (SNPs) were compared across five Colombian populations using the CÓDIGO genomic diversity database. Principal component analysis (PCA) was performed to assess genetic clustering, and Pearson correlation coefficients were used to assess pharmacogenomic similarity. Results: PCA revealed distinct genetic clustering patterns that aligned with geographical distribution and ancestral origins. Pharmacogenomic divergence was observed between African and European ancestry groups in Colombia, with certain SNPs (e.g., rs8192675-C for metformin, rs7754840-C for DPP-4 inhibitors) showing 2- to 3-fold higher frequency in African ancestry populations. The bibliometric analysis revealed that 76.1% of studies originated from high-income countries and 68.4% of participants were of European ancestry. No studies originated from Africa or low-income countries. Conclusions: Marked ancestry-based differences in pharmacogenomic variant frequencies in Colombian populations may impact drug efficacy and risk of diabetes. The global literature shows a strong geographic and economic bias, underscoring the need for inclusive, population-specific pharmacogenomic research. These findings offer a foundation for implementing precision diabetes therapies in Latin America and advancing equitable genomic medicine. Full article

Tyrosinase catalyzes the rate-limiting steps of melanin production, posing as an important target for treating skin pigmentation. This study investigates bioactive human tyrosinase inhibitors from Xanthium strumarium L. using a combined strategy of cell lysate, cell-based, and zebrafish assays. In this study, the methanol extract of Xanthium strumarium L. was identified as a potent inhibitor against tyrosinase in a cell lysate assay utilizing human MM418C1 melanoma cells. Subsequent phytochemical analysis resulted in the isolation of 11 natural products, including 4-hydroxybenzoic acid (4HB), three nucleotides, four caffeoylquinic acids and three alkaloids. Biological activity evaluation of isolated compounds suggested that 4HB was a potent inhibitor against tyrosinase with an IC₅₀ value of 59.5 μg/mL. Further evaluations revealed that 4HB significantly reduced the melanin content by 40% at the concentration of 500 mg/mL in human MM418C1 melanoma cells. 4HB activity was finally confirmed in vivo, by the demonstration of 40% reduction in melanin production in live zebrafish at the concentration of 15.63 μg/mL. Full article