Nanoparticles (NPs)-mediated systemic mRNA delivery to reverse trastuzumab resistance for effective breast cancer therapy

Monoclonal antibody-based therapy has achieved great success and is now one of the most crucial therapeutic modalities for cancer therapy. The first monoclonal antibody authorized for treating human epidermal growth receptor 2 (HER2)-positive breast cancer is trastuzumab. However, resistance to trastuzumab therapy is frequently encountered and thus significantly restricts the therapeutic outcomes. To address this issue, tumor microenvironment (TME) pH-responsive nanoparticles (NPs) were herein developed for systemic mRNA delivery to reverse the trastuzumab resistance of breast cancer (BCa). This nanoplatform is comprised of a methoxyl-poly (ethylene glycol)-b-poly (lactic-co-glycolic acid) copolymer with a TME pH-liable linker (Meo-PEG-Dlink m -PLGA) and an amphiphilic cationic lipid that can complex PTEN mRNA via electrostatic interaction. When the long-circulating mRNA-loaded NPs build up in the tumor after being delivered intravenously, they could be efficiently internalized by tumor cells due to the TME pH-triggered PEG detachment from the NP surface. With the intracellular mRNA release to up-regulate PTEN expression, the constantly activated PI3K/Akt signaling pathway could be blocked in the trastuzumab-resistant BCa cells, thereby resulting in the reversal of trastuzumab resistance and effectively suppress the development of BCa.

RUNX3 regulates trastuzumab resistance of gastric cancer cells: a metabolomic analysis based on UPLC-Q Exactive Focus Orbitrap mass spectrometry / 南方医科大学学报

OBJECTIVE@#To explore the role of Runt-related transcription factor 3 (RUNX3) in metabolic regulation of trastuzumab-resistant gastric cancer cells and investigate the mechanism of RUNX3 knockdown-mediated reversal of trastuzumab resistance.@*METHODS@#We performed a metabolomic analysis of trastuzumab-resistant gastric cancer cells (NCI N87R) and RUNX3 knockdown cells (NCI N87R/RUNX3) using ultra performance liquid chromatography (UPLC) coupled with Q Exactive Focus Orbitrap mass spectrometry (MS). Multivariate combined with univariate analyses and MS/MS ion spectrums were used to screen the differential variables. MetaboAnalyst 5.0 database was employed for pathway enrichment analysis. Differential metabolites-genes regulatory relationships were constructed based on OmicsNet database. The changes in GSH/GSSG and NADPH/NADP ratios in NCI N87R/RUNX3 cells were measured using detection kits.@*RESULTS@#The metabolic profile of NCI N87R cells was significantly altered after RUNX3 knockdown, with 81 differential metabolites identified to contribute significantly to the classification, among which 43 metabolites were increased and 38 were decreased (P < 0.01). In NCI N87R cells, RUNX3 knockdown resulted in noticeable alterations in 8 pathways involving glutamine metabolism, glycolysis, glycerophospholipid, nicotinate-nicotinamide and glutathione metabolism, causing also significant reduction of intracellular GSH/GSSG and NADPH/NADP ratios (P < 0.01). The differential metabolites-genes network revealed a regulatory relationship between the metabolic molecules and genes.@*CONCLUSION@#RUNX3 reverses trastuzumab resistance in gastric cancer cells by regulating energy metabolism and oxidation-reduction homeostasis and may serve as a potential therapeutic target for trastuzumab-resistant gastric cancer.

Mechanisms of curcumin to reverse herceptin resistance in gastric cancer cells / 药学学报

This study is aimed to investigate the potential mechanisms of herceptin-acquired resistance and curcumin to reverse resistance in NCI N87/R gastric cancer cells. Western blot was used to evaluate the effect of curcumin on the expression of IκBα, NF-κBp65, HER-2, caspase-3, Bcl-2 and Bax in herceptin resistant cells; Annexin V-FITC/PI was exploited to analyze the effect of curcumin on cell apoptosis; Caspase kit was used to evaluate the effect of curcumin on the enzymatic activity of caspase-3, 8 and 9. The results showed a low expression of IκBα in the cytoplasm and a high expression of NF-κBp65 in the nucleus of NCI N87/R cells. Correspondingly, inhibition of NF-κB pathway by EVP4593, a specific NF-κB inhibitor, preferentially reduced cell viability of NCI N87/R cells, indicating the activation of NF-κB pathway in NCI N87/R cells. Curcumin preferentially reduced cell proliferation and inhibited NF-κB signaling pathway of NCI N87/R cells, downregulated the expression of HER-2 and Bcl-2, upregulated the expression of Bax, increased the activity of caspase-3, 8 and 9. Taken together, our study demonstrates the correlation between herceptin resistance acquirement of NCI N87 cells and the activation of NF-κB pathway. Moreover, curcumin reverses herceptin resistance of NCI N87 cells possibly by inhibiting NF-κB pathway and inducing cell apoptosis.

Advances in inhibitors of PI3K/Akt/mTOR pathway in treatment of advanced breast cancer / 肿瘤

The activation of phosphatidylinositol 3-kinase/serine-threonine protein kinase (PI3K/Akt) signaling pathway plays an important role in cell proliferation, metastasis and apoptosis, and it has been proved to be associated with resistance to aromatase inhibitors (AIs) and trastuzumab in patients with breast cancer. The clinical trial of estrogen receptor-positive advanced breast cancer has revealed that the targted therapy of inhibitors of PI3K/Akt signaling pathway in combination with AIs/human epidermal growth factor receptor-2 (HER2) could achieve a good response and improve the progression-free survival. The study and clinical application of everolimus, an inhibitor of PI3K/Akt/mammalian target of rapamycin (mTOR) signaling pathway, are most ripe. This review focuses on the advances in the role of everolimus in the treatment of recurrent, metastatic and resistant breast cancer.