Triple-negative breast cancer (TNBC) represents 10–20% of breast cancers and is characterized by the absence of estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2 expression, leaving cytotoxic chemotherapy as the main systemic treatment. However, rapid development of resistance, via drug efflux, enhanced DNA repair, apoptosis evasion, epithelial-to-mesenchymal transition, and tumor microenvironment protection, limit long-term efficacy. Small interfering RNA (siRNA) therapeutics can silence key resistance drivers, but their clinical potential is hindered by instability, poor biodistribution, and off-target effects. Nanocarrier-based delivery systems offer solutions by protecting siRNA, enhancing tumor accumulation, enabling targeted intracellular release, and permitting co-delivery with chemotherapeutics for synergistic effects. We conducted a narrative review in PubMed from database inception to August 2025. The included studies demonstrated that lipid, polymeric, inorganic, and hybrid nanocarriers can achieve efficient target knockdown, reverse drug resistance mechanisms, and significantly enhance antitumor responses in resistant TNBC models. Several platforms also reduced metastatic spread and improved survival in vivo. While preclinical results are compelling, clinical translation remains limited by incomplete safety profiling and heterogeneity in delivery efficiency. This review synthesizes mechanistic insights and delivery innovations, outlining a roadmap for translating siRNA-loaded nanocarriers into effective therapies for chemoresistant TNBC.

Background: Endometrial cancer (EC) is the most common gynecologic malignancy in developed countries. Despite advances in diagnosis and treatment, recurrence and mortality remain significant concerns. The neutrophil-to-lymphocyte ratio (NLR), a marker of systemic inflammation, has shown prognostic value in several malignancies, but its utility in EC remains underexplored. Objective: To evaluate the prognostic significance of the preoperative NLR in patients with endometrial cancer undergoing primary surgical treatment. Methods: We conducted a retrospective cohort study including 398 patients with histologically confirmed endometrial adenocarcinoma surgically treated at a tertiary cancer center. Preoperative complete blood counts were used to calculate NLR, and a cutoff value of 2.27 was determined through Receiver Operating Characteristic (ROC) analysis. Survival outcomes were assessed using Kaplan–Meier analysis and Cox proportional hazards modeling. Results: Patients with NLR ≥ 2.27 had significantly reduced median overall survival (OS) compared to those with NLR < 2.27 (72.3 vs. 92.8 months, p = 0.008). In multivariate analysis, elevated NLR remained an independent predictor of poorer OS (HR = 1.87; 95% CI: 1.156–3.017; p = 0.011), alongside age ≥ 64 years, lymphovascular space invasion (LVSI), lymph node involvement, and distant metastases. ROC analysis yielded an Area Under the Curve (AUC) of 0.646 for NLR. Notably, vaginal brachytherapy was associated with improved survival (HR = 0.53; p = 0.026), while other adjuvant therapies were not independently significant. Conclusions: Preoperative NLR is an accessible, independent prognostic biomarker in endometrial cancer and may serve as a surrogate indicator of tumor-promoting inflammation and immune dysregulation. Its integration into preoperative assessment could enhance risk stratification and guide personalized treatment strategies. However, findings should be interpreted in light of the study’s retrospective design, single-center setting, and lack of molecular classification data. Prospective validation is warranted to confirm its clinical utility.