Improvement of ACK1-targeted therapy efficacy in lung adenocarcinoma using chloroquine or bafilomycin A1

Abstract Background Activated Cdc42-associated kinase 1 (ACK1) is a promising druggable target for cancer, but its inhibitors only showed moderate effects in clinical trials. The study aimed to investigate the underlying mechanisms and improve the antitumor efficacy of ACK1 inhibitors. Methods RNA-seq was performed to determine the downstream pathways of ACK. Using Lasso Cox regression analysis, we built a risk signature with ACK1-related autophagy genes in the lung adenocarcinoma (LUAD) patients from The Cancer Genome Atlas (TCGA) project. The performance of the signature in predicting the tumor immune environment and response to immunotherapy and chemotherapy were assessed in LUAD. CCK8, mRFP-GFP-LC3 assay, western blot, colony formation, wound healing, and transwell migration assays were conducted to evaluate the effects of the ACK1 inhibitor on lung cancer cells. A subcutaneous NSCLC xenograft model was used for in vivo study. Results RNA-seq revealed the regulatory role of ACK1 in autophagy. Furthermore, the risk signature separated LUAD patients into low- and high-risk groups with significantly different prognoses. The two groups displayed different tumor immune environments regarding 28 immune cell subsets. The low-risk groups showed high immune scores, high CTLA4 expression levels, high immunophenoscore, and low DNA mismatch repair capacity, suggesting a better response to immunotherapy. This signature also predicted sensitivity to commonly used chemotherapy and targeted drugs. In vitro, the ACK1 inhibitors (AIM-100 and Dasatinib) appeared to trigger adaptive autophagy-like response to protect lung cancer cells from apoptosis and activated the AMPK/mTOR signaling pathway, partially explaining its moderate antitumor efficacy. However, blocking lysosomal degradation with chloroquine/Bafilamycine A1 or inhibiting AMPK signaling with compound C/shPRKAA1 enhanced the ACK1 inhibitor’s cytotoxic effects on lung cancer cells. The efficacy of the combined therapy was also verified using a mouse xenograft model. Conclusions The resulting signature from ACK1-related autophagy genes robustly predicted survival and drug sensitivity in LUAD. The lysosomal degradation inhibition improved the therapeutic effects of the ACK1 inhibitor, suggesting a potential role for autophagy in therapy evasion

Inhibitory effects of platinum nanoparticles coated with polyethylene glycol and conjugated with Rutin on the MCF-7 breast cancer cell line

The objective of this work is to characterize the anticancer mechanism of platinum nanoparticles coated with polyethylene glycol and conjugated with Rutin (Rutin-PEG-PtNPs) in a breast cancer cell line. PtNPs were synthesized using Dendrobium officinale extract, coated with PEG, conjugated with Rutin, and characterized by the FT-IR, XRD, DLS, and TEM. The viability of the breast cancer cells (MCF-7) and normal breast cells (MCF-10A) after treatment with PEG-PtNPs and Rutin-PEG-PtNPs was studied by the MTT assay. Superoxide dismutase (SOD) and catalase (CAT) activity, MDA level, and LDH leakage in the PEG-PtNPs and Rutin-PEG-PtNPs were measured. The expression of the p53, Bax, Bcl-2, and caspase −8, and −9 genes, as well as the NF-κB and IL-6 levels in the Rutin-PEG-PtNPs treated cells, were investigated by qPCR and ELISA assays. Results demonstrated that the NPs were in a size range of 30 to 60 nm. The Rutin-PEG-PtNPs showed greater cytotoxic effects on breast cancer cells (IC50: 45.5 µg/mL) than normal breast cells (IC50: 69.4 µg/mL). The expression of the p53, Bax, caspase-8, and −9 was upregulated by 1.96, 1.84, 1.31, and 2.79 folds, while the expression of the Bcl-2 was reduced in Rutin-PEG-PtNP-treated cells. The activity of the SOD and CAT decreased, while the LDH leakage and MDA levels increased after treating the cells with Rutin-PEG-PtNPs. Also, the NF-κB and IL-6 levels in the cell cultures treated with Rutin-PEG-PtNPs were reduced by 22.6 and 17.0 %, respectively. Rutin-PEG-Pt indicated promising inhibitory potential against MCF-7 cells