Panaxadiol (PD) is a bioactive dammarane triterpenoid with limited antiproliferative potency, and systematic optimization of its C3 and C12 positions remains underexplored. Here, a stepwise, site-differentiated strategy was established by combining selective C3 esterification with late-stage C12 diversification through a chloroacetyl-piperazine linker, affording 23 PD derivatives and enabling complementary C3/C12 structure-activity analysis. Antiproliferative screening in AGS gastric cancer cells identified compounds 6, 11, and 17 as the most active analogues, with IC50 values of 8.41, 5.08, and 6.78 μM, respectively, all outperforming 5-fluorouracil under identical conditions. Compound 6 provided a relatively favorable balance between low-micromolar activity and preservation of non-malignant GES-1 cells within a defined concentration range and was therefore selected for mechanistic investigation. Transcriptomic profiling identified 298 differentially expressed genes associated with cellular stress, cytokine signaling, epithelial growth regulation, and extracellular remodeling, whereas metabolomic analysis revealed marked perturbation of glycerophospholipid, choline, polyunsaturated fatty acid, and glutathione metabolism. Integrated analysis highlighted membrane-lipid remodeling, redox dysregulation, and ferroptosis-related processes as central features of the response. These findings establish a modular platform for PD optimization and identify compound 6 as a promising lead for further anti-gastric cancer development.

Glaucoma drainage device (GDD) surgery is frequently limited by postoperative fibroblast proliferation, leading to device failure and the need for revision procedures. In this work, we developed a spray-assisted layer-by-layer (LbL) drug delivery system for GDD surfaces intended to enable localized release of antiproliferative agents, as a proof-of-concept approach toward more standardized patient care. Multilayer thin films composed of poly(β-amino ester) (PBAE) and a 5-fluorouracil (5-FU) and β-cyclodextrin (β-CD) complex (5-FU:β-CD) were fabricated, without (type A films) and with (type B films) graphene oxide (GO) barrier layers. Film growth was monitored by ultraviolet-visible spectroscopy (UV-Vis) and vacuum ultraviolet spectroscopy (VUV), confirming consistent, sequential deposition; type A films exhibited lower variability than GO-containing type B films. Drug release studies revealed a rapid burst release within the first 5 min, followed by a plateau, regardless of GO incorporation, indicating that sustained drug release was not achieved under the current film architecture. Cell cycle analysis confirmed that β-CD complexation preserved the biological activity of 5-FU, which induced an S-phase arrest in a dose-dependent manner. Although further optimization of film architecture and composition is required to improve release control and achieve sustained delivery, this study demonstrates the feasibility of spray-assisted LbL coatings as a localized drug delivery strategy for GDD surfaces. Overall, these findings support the proof-of-concept nature of this approach and identify key parameters that must be optimized before translational applicability can be established.

Tannic acid grafting provides a practical strategy for introducing bioactive phenolic functionality into microbial polysaccharides for multifunctional hydrogel design. Herein, tannic acid-modified succinoglycan (SG-TA) was prepared through an ascorbic acid/ H2O2-mediated free-radical process. Spectroscopic, thermal, and purification-control analyses were consistent with covalent incorporation of tannic acid-derived moieties into SG, while characteristic structural features of the SG framework remained evident after modification. SG-TA exhibited tannic acid-equivalent phenolic contents of up to 321.9 mg TAE/g and markedly enhanced antioxidant and antibacterial activities compared with native SG. SG-TA was subsequently incorporated into a poly(vinyl alcohol) (PVA)/borax network to form dynamic SG-TA/PVA/borax (STPB) hydrogels based on reversible interactions. The hydrogels exhibited composition-dependent viscoelasticity, rapid rheological recovery, macroscopic self-rejoining, enhanced deformability, antioxidant and antibacterial functionality, and preliminary cytocompatibility. Time-dependent phenolic release showed that SG-TA-derived phenolic species were partially released from the network, indicating contributions from both matrix-associated and releasable functionality. The reversible network also enabled pH- and glucose-responsive release of 5-fluorouracil as a model small-molecule drug. These findings demonstrate the potential of SG-TA as an intrinsically bioactive microbial polysaccharide for multifunctional, self-healing, and stimuli-responsive drug-delivery hydrogels.

It is known that the controlled release of anticancer drugs with low molecular weight from drug delivery systems (DDSs) based on polysaccharides such as chitosan (CS) still encounter certain difficulties because of the high hydrophilicity of the carrier. The release rate is very fast, with a burst release that is usually obvious. Therefore, finding novel systems to carry and release low molecular weight drugs such as 5-fluorouracil (5-FU) is still of interest. The impact of chitosan (CS) characteristics (deacetylation degree and molar mass), and concentration as well as of the strategy employed to fabricate porous nanocomposites CS-laponite (LAP), on the physicochemical properties of CS-LAP sponges was first investigated in the paper. Information about the incorporation of LAP within the CS-LAP nanocomposites was obtained by EDX and FTIR spectroscopy. The influence of the fabrication conditions on the physical cross-linking was evidenced first by the swelling of the composite sponges at equilibrium in distilled water, with lower values of the swelling ratio found for the composites prepared with one freeze-drying (1FD) step, than of those prepared with 2FD steps. The elastic modulus ranged between 6 and 21 kPa for CS-LAP composites prepared with 1FD, and between 2 and 10 kPa for the nanocomposites prepared with 2FD steps. The physicochemical properties of CS-LAP nanocomposite sponges were correlated with their behavior in the loading and in vitro release of 5-FU as a function of pH. It was found that the CS-LAP composites with the highest swelling ratio exhibited the fastest release of 5-FU in simulated gastric fluid (pH 2.0), with the cumulative release in the range of 85-100%, in about 60 min, at 37 °C. The CS-LAP composites with the lowest swelling ratio, displayed the slowest release rate of drug. The drug release from the double component composites was accompanied by the carrier dissolution/disintegration. To retard the release of 5-FU in the gastric environment, the drug was sealed in the porous CS-LAP nanocomposites by simple complexation of the free positive charges of CS with carboxymethylcellulose as polyanion. These systems kept their integrity at pH 2.0, pH 6.8 and phosphate buffer with pH 7.4, and released 5-FU in a controlled manner, making them suitable systems for delivery of 5-FU in both the stomach and small intestine.

Background/Objectives: Pharmacogenetic testing of the dihydropyrimidine dehydrogenase gene (DPYD) is increasingly incorporated into clinical practice to identify patients at increased risk of fluoropyrimidine-related toxicity. However, most routine assays target a limited number of well-established variants, whereas the DPYD gene demonstrates substantial population variability and may harbor rare potentially functional alleles that are not detected by conventional targeted testing. Data describing coding and splice-region DPYD variants detectable by whole-exome sequencing in Russian oncology populations remain limited. This study aimed to characterize the frequency and distribution of common, clinically relevant, and rare DPYD variants in a Russian cohort of patients receiving fluoropyrimidine-containing chemotherapy and to compare the observed allele frequencies with European and East Asian reference populations. Methods: Descriptive pharmacogenetic analysis was performed in 339 patients with malignant tumors treated with fluorouracil, leucovorin, oxaliplatin, and docetaxel (FLOT), folinic acid, fluorouracil, and oxaliplatin (FOLFOX), or folinic acid, fluorouracil, irinotecan, and oxaliplatin (FOLFIRINOX) regimens. Whole-exome sequencing was performed using Illumina technology with exome enrichment by KAPA HyperExome and a sequencing depth of at least 100×. Sequence reads were aligned to the Genome Reference Consortium Human Build 38 (GRCh38) reference genome, germline variants were called using Genome Analysis Toolkit (GATK), HaplotypeCaller, and functional annotation was performed with Ensembl Variant Effect Predictor. DPYD variants were classified according to their population frequency, predicted functional effect, ClinVar annotations, and current pharmacogenetic recommendations. Allele and genotype frequencies were calculated and descriptively compared with Genome Aggregation Database (gnomAD) v4.1.1 Non-Finnish European and East Asian populations. Results: Seventeen DPYD variants were identified. The most frequent alternative alleles were rs1801265 (24.93%), rs1801159 (17.70%), rs2297595 (11.06%), rs1801160 (7.08%), and rs17376848 (5.16%). Their distribution was generally closer to that observed in the Non-Finnish European population than in East Asian populations. The established reduced-function variant rs67376798 (c.2846A>T, p.Asp949Val) was detected in one heterozygous patient, corresponding to a carrier frequency of 0.29% and an allele frequency of 0.15%. The HapB3 proxy variant rs56038477 (c.1236G>A) was identified in 13 heterozygous patients, with a carrier frequency of 3.83% and an allele frequency of 1.92%; confirmation of the functional intronic variant rs75017182 would be required for definitive HapB3 assignment. Overall, rs67376798 or rs56038477 was detected in 14 patients (4.13%). In addition, rare variants with a cohort allele frequency below 1% were identified in 11 patients (3.24%). Among these, p.Thr65Ala, p.Thr65Met, p.Asn151Asp, and p.Val691Leu represented potentially relevant findings requiring further functional validation. Conclusions: Whole-exome analysis revealed a heterogeneous spectrum of DPYD variants in the studied Russian oncology cohort, including both established pharmacogenetic markers and rare variants that would not be captured by limited targeted panels. The overall allele-frequency pattern was predominantly similar to that of European reference populations, although several rare variants demonstrated distinct distributions. These findings support the value of population-specific characterization of DPYD and suggest that expanded sequencing approaches may complement conventional pharmacogenetic testing by identifying rare potentially functional alleles.

Twelve new thiazol-carbaldehyde thiosemicarbazone derivatives were synthesized by condensing the thiosemicarbazide derivative with the respective thiazol-2/5-carbaldehyde in methanol. The synthesized compounds were characterized by elemental analysis, ESI-mass spectrometry and FT-IR, [1]H, [13]C and [19]F NMR spectroscopy. Elemental and mass spectrometric data are consistent with the proposed structural formulas. In addition, IR and NMR spectral data evidenced the formation of the (-C[double bond, length as m-dash]N-) imine bond in all the synthesized compounds, which confirms the obtaining of the thiazol-carbaldehyde thiosemicarbazone derivatives. The molecular structures of 1, 2, 7 and 11 were determined by X-ray crystallography. These compounds exhibited an E conformation around the N2-C4, N2-C5, N3-C9 and N3-C6 bonds. The in vitro cytotoxic activity of the synthesized thiosemicarbazones was evaluated against five human tumor cell lines: HuTu80 (duodenum adenocarcinoma), DU145 (prostate carcinoma), MCF-7 (breast adenocarcinoma), M14 (amelanotic melanoma) and HT-29 (colon adenocarcinoma), using the sulforhodamine B assay. Besides, BALB/3T3 cells (mouse fibroblast) were also tested as representative of normal cells. The HuTu80, DU145 and BALB/3T3 cell lines were obtained from ATCC (American Type Culture Collection), while the MCF-7, M-14 and HT-29 cell lines were obtained from NCI (National Cancer Institution). Among the tested human tumor cell lines, compounds 3 and 6 showed greater cytotoxicity (IC50 = 10.58 and 9.63 µM, respectively) than the other tested compounds against the MCF-7 tumor cell line. Compounds 3 and 6 showed similar cytotoxicity in comparison to the reference compound (5-fluorouracil). However, 3 was more innocuous against 3T3 normal cells. Theoretical investigations showed the effect of the substituent groups on the electronic properties of compounds 3 and 6. HOMO-LUMO and global reactivity analyses indicate that 3 and 6 possess higher chemical reactivity and exhibit lower kinetic stability than the reference inhibitor BI2536 of the Polo-like kinase 1. Compound 3 containing the fluorophenyl substituent on the thiazole ring revealed to be a stronger electrophile with a greater tendency to accept electrons from residues present in the PLK1 pocket. Molecular docking suggested that 3 and 6 engage key PLK1 residues through hydrophobic, hydrogen-bonding, and π-stacking interactions while BI2536 provides a broader and more established interaction profile. These findings demonstrate that compounds 3 and 6 have the potential to be considered as promising lead compounds for further investigation.

5-Fluorouracil (5-FU)-based regimens are a cornerstone of colorectal cancer (CRC) chemotherapy. Levofloxacin (LVF), a widely used fluoroquinolone antibiotic, has been reported to exhibit anticancer properties. We investigated LVF's ability to enhance CRC chemosensitivity to 5-FU in cell lines, subcutaneous xenografts (Balb/c-nude mice), and spontaneous intestinal tumors (Apc[min/+] mice). LVF potentiated 5-FU-induced apoptosis in vitro and in vivo. Mechanistically, LVF induced mitochondrial dysfunction in CRC cells, marked by reactive oxygen species (ROS) accumulation, increased mitochondrial ROS, and loss of mitochondrial membrane potential. TP53 and downstream effectors NOXA and BBC3 mediate between LVF-induced mitochondrial damage and 5-FU sensitization. LVF-induced DNA damage response (DDR) and subsequent oxidative phosphorylation (OXPHOS) upregulation trigger mitochondrial damage and TP53 activation. Importantly, we confirmed that the canonical LVF target TOP2A and the reported LVF effector ribosomal S6 kinase 4 (RSK4) are dispensable for LVF-mediated sensitization. Thus, LVF acts as a non-canonical 5-FU chemosensitizer in TP53-WT CRC via DDR-TP53-mitochondrial apoptosis activation, supporting clinical repurposing.

The advent of copolymerization techniques involving α-lipoic acid (LA) and vinyl monomers has significantly transformed the synthetic paradigms of self-immolative poly(disulfide)s. Further leveraging their structure-function-property-design interplay and eventually creating advanced materials are highly appreciated yet remains largely unexplored. A key advancement of this study lies in bridging the divide between controlled LA/vinyl copolymerization and practical materials, by fabricating biodegradable anti-melanoma nanomedicine derived from well-defined self-immolative poly(disulfide)s. To do so, reversible addition-fragmentation chain transfer (RAFT) copolymerization of LA and 2,6-diaminopyridine-substituted vinyl monomer (DAP) is first conducted, endowing glutathione (GSH)-degradable amphiphilic poly(disulfide)s vehicles, P(DAP-co-LANa), equipping hetero-complementary H-bonding DAP motifs toward the chemotherapeutic fluorouracil-1-acetic acid (FUA). On the other hand, FUA is tethered onto the photothermal agent IR780 to afford multifunctional prodrug FUA780, incorporating an H-bonding array, chemotherapeutic, and photothermal activities. DAP/FUA H-bonding interaction-mediated assembly thus endow the construction of targeted smart nanomedicine FUA780@P(DAP-co-LANa). Moreover, to effectively cross the skin barrier, FUA780@P(DAP-co-LANa) is embedded within dissolvable microneedles, indeed standing out in malignant melanoma treatment, via spatiotemporal cargo delivery and synergistic chemo/photothermal therapy (CT/PTT). Such a controlled synthetic approach and well-defined structural characteristics through LA/vinyl copolymerization are anticipated to serve as a pivotal foundation for advancing the design principles underlying dynamic material paradigms.

Precision oncology aims to guide treatment decisions using biomarkers. While DNA-based panels are increasingly applied, RNA transcriptomics remain underused due to limited datasets and the absence of robust models. To address this, we assembled the largest transcriptomic resource for drug response prediction to date, spanning 91 cohorts, 5,675 patients, nine cancer types, and six frontline therapies: anti-PD-1/PD-L1 immune-checkpoint inhibitors, trastuzumab, bevacizumab, BRAF inhibitors, paclitaxel, and FAC/FEC (fluorouracil-adriamycin-cyclophosphamide/fluorouracil-epirubicin-cyclophosphamide) chemotherapy. A supervised machine-learning framework, EXPRESSO (EXpression-Profile-RESponSe-Optimizer), was developed to predict treatment response from pre-treatment transcriptomes by integrating drug targets and context-specific biomarkers. EXPRESSO effectively predicted patient treatment responses across therapies, outperforming 20 published transcriptomic signatures and other machine learning methods. Prospective validation on 22 independent cohorts confirmed that performance generalized beyond cross-validation. The EXPRESSO signature additionally stratified progression-free survival in immune checkpoint blockade-treated cohorts, demonstrating prognostic value beyond binary response prediction. Robustness analysis revealed that predictive performance plateaued for some therapies with increasing training cohorts but continued to improve for others. These findings suggest inherent limits of supervised brute-force learning for certain treatments, but additional data and deeper mechanistic modeling may further enhance transcriptomics-based predictors.

Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome is a rare mitochondrial disorder characterized by impaired oxidative phosphorylation and reduced ATP production, resulting in increased organ vulnerability to metabolic stress. Fluoropyrimidine agents, such as 5-fluorouracil (5-FU), are widely used to treat colorectal cancer and can induce gastrointestinal toxicity not only through inhibition of thymidylate synthase and suppression of nucleic acid synthesis but also via RNA misincorporation, translational defects, and mitochondrial dysfunction in intestinal epithelial cells. The coexistence of metabolic vulnerability associated with m.3243A>G-related mitochondrial dysfunction and drug-induced mitochondrial injury may synergistically exacerbate intestinal toxicity, potentially leading to severe enteritis. A 40-year-old woman with m.3243A>G-associated mitochondrial disease within the MELAS spectrum underwent radical resection for perforated rectal cancer with synchronous liver metastases. Her postoperative course was uneventful, and she was discharged without complications. CapeOX therapy (capecitabine plus oxaliplatin) was initiated as adjuvant chemotherapy. Ten days after the start of the third cycle, she developed intermittent fever, abdominal distension, and diarrhea. Computed tomography revealed diffuse edema throughout the small intestine with massive ascites. Malignant peritonitis was considered unlikely based on imaging, ascites analysis, and cytology, whereas infectious enteritis was not strongly suspected based on the clinical course. Chemotherapy-induced enteritis associated with CapeOX was therefore strongly suspected, and the regimen was discontinued. The gastrointestinal symptoms improved, and tumor marker levels normalized. This case suggests that underlying mitochondrial dysfunction may enhance fluoropyrimidine-related intestinal toxicity, indicating that careful risk assessment and close monitoring are required when administering chemotherapy to patients with underlying mitochondrial disorders.

A 63-year-old woman with microsatellite instability-high metastatic colorectal cancer experienced tumor enlargement and worsening general condition after the first dose of pembrolizumab. This was determined to represent true progression rather than pseudoprogression. Second-line treatment with fluorouracil, leucovorin, and oxaliplatin plus bevacizumab achieved a complete response sustained for over three years. Comprehensive genomic profiling testing performed during chemotherapy detected a lamin A/C-neurotrophic tyrosine receptor kinase (NTRK) 1 fusion, and NTRK targeted therapy is planned at the time of the next progression. This case report provides valuable information on the clinical course of this rare molecular subtype and emphasizes the importance of comprehensive genomic profiling for detecting NTRK fusions, which, although rare overall, are relatively more frequent in MSI-high than in microsatellite-stable colorectal cancer.

A woman in her 50 s presented with invasive mucinous adenocarcinoma of unknown primary origin 18 years after undergoing radical hysterectomy and two-dimensional chemoradiotherapy for FIGO stage IB1 cervical cancer. Over two decades, the patient developed chronic radiation-induced complications, including pelvic abscesses, enterocutaneous fistulas, and progressive renal impairment. These chronic changes formed a 'pelvic cocoon' that masked the development of a secondary malignancy. Diagnosis was achieved through random biopsies of the fistula site, whilst repeated endoscopies were negative. Management required complex decision-making, resulting in the selection of a modified 'folinic acid, fluorouracil, and irinotecan' regimen due to severe renal dysfunction (creatinine clearance < 20 mL/min) and UGT1A1*28/*28 homozygosity, adhering to stringent European safety standards. This case illustrates delayed recognition of secondary malignancy arising from chronic inflammatory and post-treatment changes, emphasising the need for a high index of clinical suspicion and individualised therapeutic strategies in long-term cancer survivors.

This study aims to present the diagnosis, treatment process, and clinical course of a patient with advanced rectal adenocarcinoma presenting with rare duodenal metastases. A 47-year-old male patient presented with constipation. A mass obstructing the entire lumen was detected in the rectosigmoid region, and the biopsy result was reported as rectal adenocarcinoma. Clinical staging was determined as T4aN2bM0. Due to the obstruction, a loop sigmoidostomy was performed, and Total Neoadjuvant Therapy (TNT) was planned. Within the scope of TNT, 5- Fluorouracil (5-FU), Oxaliplatin, Capecitabine, and 25 fractions of radiotherapy were administered. Surgically, Low Anterior Resection (LAR) was performed, and pathology confirmed pT4N2, with the presence of lymphovascular and perineural invasion. In the fifth postoperative month, preaortic and paraaortic lymphadenopathy was detected; a KRAS mutation was identified. Partial regression was observed in the lymph nodes following the new chemotherapy regimen (5-FU +Irinotecan+Bevacizumab), but cholestasis developed. Imaging and Endoscopic Retrograde Cholangiopancreatography (ERCP) revealed ulcerative metastatic masses in the duodenum and ampulla of Vater regions. Biopsy results and immunohistochemical analyses (CDX2, SATB2, Beta-Catenin) confirmed colon adenocarcinoma metastasis. Next-generation sequencing (NGS) analysis showed a recurrent KRAS mutation, stable microsatellite stability(MSI), and intact Mismatch Repair (MMR). Although symptomatic relief was achieved with biliary drainage and a duodenal stent, advanced metastases (liver, adrenal, bone) developed. Duodenal metastasis in patients with rectal adenocarcinoma is rare but clinically severe and has a poor prognosis. This case demonstrates the rare metastatic pathways of advanced colorectal cancer, management challenges, and palliative treatment strategies. Keywords: Rectal cancer; Duodenal metastasis; Intraluminal metastasis; KRAS mutation; Colorectal cancer.