Background/Objectives: Deficient mismatch repair (dMMR) and microsatellite instability-high (MSI-H) colorectal cancer (CRC) are highly sensitive to immune checkpoint blockade. We evaluated the efficacy, safety, and clinical maturity of neoadjuvant PD-1-based immunotherapy in localized disease. Methods: This PRISMA-compliant systematic review included prospective studies of neoadjuvant PD-1-based therapy in localized dMMR/MSI-H CRC. Proportions were pooled on the logit scale using inverse-variance random-effects models with the Paule–Mandel estimator. Pathologic complete response (pCR) was the primary outcome; major pathologic response (MPR), immune-related adverse events (irAEs), surgery, clinical complete response (cCR), organ preservation, and long-term outcomes were secondary outcomes. Results: Five prospective studies were included. Four studies, comprising 305 treated patients and 292 pathologically evaluable patients, contributed five treatment arms to the quantitative synthesis. The pooled pCR proportion was 0.65 (95% CI, 0.54–0.74), and the pooled MPR proportion was 0.89 (95% CI, 0.79–0.94). Exploratory subgroup analyses suggested higher response proportions with combination regimens, but clinical and methodological differences confounded these predominantly indirect comparisons. Any-grade irAEs occurred in 0.54 (95% CI, 0.36–0.71), whereas grade ≥3 irAEs occurred in 0.06 (95% CI, 0.04–0.10). The pooled surgery proportion was 0.96 (95% CI, 0.86–0.99), although this outcome largely reflected protocol-mandated surgery. cCR and organ preservation were promising in selected rectal-cancer cohorts. Survival and recurrence data were immature and unsuitable for quantitative pooling. Conclusions: Neoadjuvant PD-1-based immunotherapy is a highly promising investigational strategy for localized dMMR/MSI-H CRC. Nevertheless, predominantly early-phase evidence, indirect comparisons, heterogeneous endpoints, and limited follow-up preclude definitive conclusions regarding routine clinical adoption.

Background/Objectives: Hepatocellular carcinoma, or liver cancer, is the sixth most common cancer worldwide and the third leading cause of cancer-related mortality. Therefore, this study aimed to develop and optimise etodolac-loaded sodium deoxycholate-stabilised shellac-based polymeric nanoparticles (ETD-SDS-SHNPs) to improve the pharmacokinetic profile of etodolac (ETD) in HepG2 human hepatocellular carcinoma (HCC) cells. Methods: The nanoprecipitation method was used to prepare ETD-SDS-SHNPs, which were then optimised using a Box–Behnken design and evaluated for particle size (PS), zeta potential (ZP), entrapment efficiency (EE), solid-state characterization, and in vitro drug dissolution. Furthermore, in vivo oral bioavailability, cytotoxicity, cellular uptake, and cell cycle progression were assessed. Results: The optimised ETD-SDS-SHNPs formulation showed an average PS of 192 ± 1.50 nm, ZP of −20.2 ± 0.4 mV, and EE of 81.6 ± 1.42%. Differential scanning calorimetry and X-ray diffraction confirmed the reduced crystallinity of ETD-SDS-SHNPs, indicating partial amorphisation of the drug in the formulation. Field-emission scanning electron microscopy revealed predominantly spherical nanoparticles with relatively smooth surfaces. The peak plasma concentration (C_max) of ETD-SDS-SHNPs (11.86 ± 0.12 µg/mL) was significantly higher than that of the pure ETD (7.15 ± 0.14 µg/mL). Similarly, the AUC_0–t for ETD-SDS-SHNPs (351.63 ± 4.59 µg·h/mL) was approximately 1.48-fold greater than that of the pure drug (236.09 ± 4.60 µg·h/mL), indicating enhanced bioavailability. ETD-SDS-SHNPs demonstrated dose-dependent enhancement of cytotoxicity against HepG2 cells, accompanied by S-phase cell cycle arrest and increased cellular uptake. Conclusions: ETD-SDS-SHNPs formulation offers an enhanced passive, efficient, and safer nanocarrier platform for repurposing etodolac in liver cancer therapy, showing significant promise for improving clinical outcomes in HCC treatment.

Background: Nicotine pouches release nicotine and other soluble formulation constituents directly at the oral mucosal surface, but the acute cellular effects of high-strength commercial products remain incompletely characterized. Objective: To compare the acute toxicity of aqueous extracts prepared from products labeled 20 mg and 30 mg nicotine per pouch in primary human oral keratinocytes (HOKs), using complementary functional, biochemical, molecular, flow cytometric, and ultrastructural endpoints. Methods: Primary HOKs were exposed for 24 h to aqueous extracts of the two products. Concentration-response cytotoxicity and half-maximal inhibitory concentrations (IC₅₀) were determined by MTT assay. Each extract was then tested at its own MTT-defined IC₅₀. Cellular morphology was examined microscopically; CAT and SOD activities and MDA and NO levels were measured to characterize redox status; cell-death populations were quantified by Annexin V-FITC/propidium iodide flow cytometry; TP53 and EGFR transcripts were assessed by quantitative real-time PCR; and ultrastructural alterations were examined by transmission electron microscopy. Results: Both extracts reduced MTT-derived viability as extract concentration increased. The 30 mg product extract had a lower IC₅₀ than the 20 mg product extract (49.6% versus 83.2% of the stock extract), indicating greater cytotoxic potency. At the selected exposure concentrations, both extracts reduced CAT and SOD activities, increased MDA and NO levels, decreased the viable cell fraction, and produced predominantly necrotic cell death. TP53 mRNA increased to 2.31-fold and 3.16-fold of control levels after exposure to the 20 mg and 30 mg extracts, respectively, whereas EGFR mRNA decreased to 0.62-fold and 0.47-fold. Electron microscopy showed mitochondrial swelling, cristae disruption, chromatin condensation, cytoplasmic vacuolization, and plasma membrane injury, with more extensive alterations after exposure to the 30 mg product extract. Conclusion: Commercial high-strength nicotine pouch extracts induce acute oxidative, molecular, and structural injury in primary oral keratinocytes. The 30 mg product extract showed greater cytotoxic potency, but the use of whole-product extracts means that the observed effects cannot be attributed to nicotine alone.

Background/Objectives: Colorectal cancer (CRC) is among the most diagnosed malignancies and is a leading cause of cancer-related deaths globally. Beyond canonical CRC driver mutations, additional molecular alterations such as dysregulated gene expression and epigenetic reprogramming shape the disease behavior and may represent potential candidate biomarkers. The Four and a Half LIM domain (FHL) family, specifically FHL1, has been implicated as a tumor suppressor in CRC epithelial cells. However, FHL1 expression is reduced in CRC and whether this reduction in heterogenous tumors is cell type-specific remains unknown. Methods: In this study, we integrated bulk genomic, transcriptomic and survival data from the cancer genome atlas (TCGA) with publicly available single-cell transcriptomic and epigenomic datasets to identify where and how FHL1 expression is dysregulated in CRC. Results: While somatic mutations of FHL family genes are infrequent and non-recurrent, downregulation of FHL1 in CRC tissue is evident and shows a modest association with longer survival that is not independent of clinical factors. Notably, single-cell analysis across three independent studies revealed that FHL1 expression is largely restricted to fibroblasts and is specifically downregulated in cancer-associated fibroblasts (CAFs). FHL1 expression is inversely associated with activated CAF markers FAP and ACTA2, while normal fibroblast markers WNT2B and RSPO3 demonstrate a similar expression pattern to FHL1. Finally, chromatin accessibility at the FHL1 promoter was substantially reduced in CAFs relative to pre-CAFs and normal fibroblasts. Conclusions: Our study identifies that FHL1 downregulation is specific to CAFs in CRC and is accompanied by chromatin inaccessibility within the FHL1 promoter in CAFs.