Tamoxifen is currently used for the treatment of both early and advanced estrogen receptor (ER) positive breast cancer in pre- and post-menopausal women. However, using tamoxifen routinely to inhibit endogenous or exogenous estrogen effects is occasionally difficult because of its potential side effects. The aim of this study is to design a local drug delivery system to encapsulate tamoxifen for observing their efficacy of skin penetration, drug accumulation and cancer therapy. A cationic liposome-PEG-PEI complex (LPPC) was used as a carrier for the encapsulation of tamoxifen and forming ‘LPPC/TAM’ for transdermal release. The cytotoxicity of LPPC/TAM was analyzed by MTT. The skin penetration, tumor growth inhibition and organ damages were measured in xenograft mice following transdermal treatment. LPPC/TAM had an average size less than 270 nm and a zeta-potential of approximately 40 mV. LPPC/TAM displayed dramatically increased the cytotoxic activity in all breast cancer cells, especially in ER-positive breast cancer cells. In vivo, LPPC drug delivery helped the fluorescent dye penetrating across the skim and accumulating rapidly in tumor area. Administration of LPPC/TAM by transdermal route inhibited about 86 % of tumor growth in mice bearing BT474 tumors. This local treatment of LPPC/TAM did not injury skin and any organs. LPPC-delivery system provided a better skin penetration and drug accumulation and therapeutic efficacy. Therefore, LPPC/TAM drug delivery maybe a useful transdermal tool of drugs utilization for breast cancer therapy.

A cationic liposome-PEG-PEI complex (LPPC) was employed as a carrier for achieving targeted delivery of drug to human epidermal growth factor receptor-2 (HER2/neu)-expressing breast cancer cells. LPPC can be easily loaded with an anti-tumor drug and non-covalently associated with an anti-tumor antibody such as Herceptin that is clinically used to rapidly form immunoparticles within 1 h. Drug-loaded LPPC have an average size about 250 nm and a zeta potential of about 40 mV. Herceptin was complexed onto surface of the LPPC to form the drug/LPPC/Herceptin complexes. The size of curcumin/LPPC/Herceptin complexes were 280 nm and the zeta potentials were about 23 mV. Targeting ability of this delivery system was demonstrated through specific binding on surface of cells and IVIS images in vivo, which showed specific binding in HER2-positive SKBR3 cells as compared to HER2-negative Hs578T cells. Only the drug/LPPC/Herceptin complexes displayed dramatically increased the cytotoxic activity in cancer cells. Both in vitro and in vivo results indicated that Herceptin adsorbed on LPPC directed the immunocomplex towards HER2/neu-positive cells but not HER2/neu-negative cells. The complexes with either component (curcumin or doxorubicin) used in the LPPC-delivery system provided a better therapeutic efficacy compared to the drug treatment alone and other treatment groups, including clinical dosages of Herceptin and LipoDox, in a xenografted model. LPPC displays important clinical implications by easily introducing a specific targeting characteristic to drugs utilized for breast cancer therapy.

Background/Objectives: Breast cancer remains the leading malignancy affecting women worldwide, with significant mortality rates. This study aimed to evaluate the prognostic significance of FOXM1 expression specifically in hormone receptor-positive, HER2-negative (HR+HER2-) breast cancer patients with high KPNA2 expression, and to identify potential FOXM1-targeted therapeutic strategies for this patient subgroup. Methods: We analyzed RNA sequencing and microarray data from three independent cohorts: Mackay Memorial Hospital patient samples, The Cancer Genome Atlas, and Gene Expression Omnibus databases. The expression levels of KPNA2, FOXM1, CCNB1, and CCNB2 were evaluated, with particular emphasis on stratifying patients based on KPNA2 expression levels. Their associations with clinical outcomes were assessed using Gene Set Enrichment Analysis and survival analyses. Results: While KPNA2 expression showed strong positive correlations with FOXM1, CCNB1, and CCNB2 across all datasets, our analysis revealed a distinct prognostic pattern in HR+HER2- breast cancer patients with high KPNA2 expressions. In this specific subgroup, low FOXM1 expression emerged as a favorable prognostic indicator, despite the generally poor prognosis associated with high KPNA2 levels. Gene Set Enrichment Analysis demonstrated significant enrichment of the G2/M checkpoint pathway in high KPNA2-expressing patients, suggesting potential therapeutic vulnerability to FOXM1 inhibition in this subgroup. Conclusions: This study establishes FOXM1 expression as a critical prognostic marker, specifically in KPNA2-high HR+HER2- breast cancer patients, where low FOXM1 levels correlate with improved survival outcomes. These findings suggest that FOXM1 inhibition could be particularly effective in patients with high KPNA2 expression, offering a novel therapeutic strategy for this specific molecular subtype. Several FOXM1 inhibitors, including thiostrepton and FDI-6, warrant investigation as potential targeted treatments for KPNA2-high HR+HER2- breast cancer patients.

Introduction: The prognostic capability of targeted sequencing of primary tumors in patients with estrogen receptor‐positive, human epidermal growth factor receptor‐2‐negative early‐stage invasive breast cancer (EBC) in a real‐world setting is uncertain. Therefore, we aimed to determine the correlation between a 22‐gene mutational profile and long‐term survival outcomes in patients with ER+/ERBB2‐ EBC.Patients and Methods: A total of 73 women diagnosed with ER+/ERBB2‐ EBC between January 10, 2004, and June 2, 2008, were followed up until December 31, 2022. Univariate and multivariate Cox models were constructed to plot the relapse‐free survival (RFS) and overall survival (OS). The log‐rank test derived p‐value was obtained. For external validation, we performed a survival analysis of 1163 comparable patients retrieved from the Molecular Taxonomy of Breast Cancer International Consortium (METABRIC) dataset.Results: At follow‐up, 16 (21.9%) patients had relapsed, while 21 (nearly 29%) harbored mutant genes. Thirty‐three missense mutations were detected in 14 genes. The median ages were 51 and 46 years in patients with and without mutations, respectively. Patients with any mutation had a 1.85‐fold higher risk of relapse (hazard ratio [HR]: 1.85, 95% confidence interval [CI]: 0.60–5.69) compared to those without any mutation. Patients who harbored any of the six genes (MAP2K4, FGFR3, APC, KIT, RB1, and PTEN) had a nearly 6‐fold increase in the risk of relapse (HR: 5.82, 95% CI: 1.31–18.56; p = 0.0069). Multivariate Cox models revealed that the adjusted HR for RFS and OS were 6.67 (95% CI: 1.32–27.57) and 8.31 (p = 0.0443), respectively. METABRIC analysis also demonstrated a trend to significantly worse RFS (p = 0.0576) in the subcohort grouped by having a mutation in any of the six genes.Conclusions: Our single‐institution tissue bank study of Taiwanese women with ER+/ERBB2‐ EBC suggests that a novel combination of six gene mutations might have prognostic capability for survival outcomes.