Core-shell cisplatin/SiO2 nanocapsules combined with PTC-209 overcome chemotherapy-Acquired and intrinsic resistance in hepatocellular carcinoma

The primary cause of cisplatin resistance in liver cancer is reduced intracellular drug accumulation and altered DNA repair/apoptosis signaling. Existing strategies to reverse cisplatin resistance have limited efficacy, as they target individual factors. This study proposes a drug delivery system consisting of a cisplatin core, a silica shell with a tetra-sulfide bond, and a PEG-coated surface (Core/shell-PGCN). The system is designed to consume glutathione (GSH) and reduce cisplatin excretion from cells, thereby overcoming acquired cisplatin resistance. In addition, Core/shell-PGCN incorporates PTC-209 (Core/shell-PGCN@PTC-209), a Bmi1 inhibitor that suppresses liver cancer stem cells (CSC), to mitigate DNA repair/apoptosis signaling and reverse intrinsic cisplatin resistance. In vivo and in vitro results demonstrate that Core/shell-PGCN@PTC-209 can comprehensively regulate GSH and CSC, reverse intrinsic and acquired cisplatin resistance, and enhance the efficacy of cisplatin in treating liver cancer. This "inner cultivation, outer action" approach may offer a new strategy for reversing cisplatin resistance in liver cancer. STATEMENT OF SIGNIFICANCE: Cisplatin resistance is widely observed in liver cancer (HCC) chemotherapy, with two mechanisms identified: acquired and intrinsic. Most strategies aimed at overcoming cisplatin resistance focus on a single perspective. This study introduces a core-shell drug delivery system (DDS) combined with HCC stem cell inhibitors, which can effectively address cisplatin resistance in HCC by targeting both acquisition and internality. Specifically, the core-shell drug delivery system can impede cisplatin efflux by neutralizing the acquired resistance factor (GSH), thus overcoming acquired resistance. Additionally, HCC stem cell inhibitors can reverse intrinsic resistance by inhibiting HCC stem cells. Therefore, this study contributes to the application of DDS in combating drug resistance in HCC and enhances its potential for clinical implementation.

Pomiferin targets SERCA, mTOR, and P-gp to induce autophagic cell death in apoptosis-resistant cancer cells, and reverses the MDR phenotype in cisplatin-resistant tumors in vivo

Drug resistance in cancer has been classified as innate resistance or acquired resistance, which were characterized by apoptotic defects and ABC transporters overexpression respectively. Therefore, to preclude or reverse these resistance mechanisms could be a promising strategy to improve chemotherapeutic outcomes. In this study, a natural product from Osage Orange, pomiferin, was identified as a novel autophagy activator that circumvents innate resistance by triggering autophagic cell death via SERCA inhibition and activation of the CaMKKβ-AMPK-mTOR signaling cascade. In addition, pomiferin also directly inhibited the P-gp (MDR1/ABCB1) efflux and reversed acquired resistance by potentiating the accumulation and efficacy of the chemotherapeutic agent, cisplatin. In vivo study demonstrated that pomiferin triggered calcium-mediated tumor suppression and exhibited an anti-metastatic effect in the LLC-1 lung cancer-bearing mouse model. Moreover, as an adjuvant, pomiferin potentiated the anti-tumor effect of the chemotherapeutic agent, cisplatin, in RM-1 drug-resistant prostate cancer-bearing mouse model by specially attenuating ABCB1-mediated drug efflux, but not ABCC5, thereby promoting the accumulation of cisplatin in tumors. Collectively, pomiferin may serve as a novel effective agent for circumventing drug resistance in clinical applications.

FIGNL1 is a potential biomarker of cisplatin resistance in non-small cell lung cancer

BACKGROUND

Fidgetin-like 1 (FIGNL1) participates in tumor resistance by playing the function of homologous recombination repair(HRR). However, the role of FIGNL1 in non-small cell lung cancer (NSCLC) is still unclear. This study aims to understand the expression of FIGNL1 in NSCLC and preliminarily explore its relationship with cisplatin resistance.

METHODS

FIGNL1 messenger RNA (mRNA) was analyzed in 1018 NSCLC tissues and 111 adjacent tissues using The Cancer Genome Atlas program. FIGNL1mRNA in cisplatin-resistant and cisplatin-sensitive cell lines was analyzed by the Gene Expression Omnibus project. FIGNL1 protein was detected in 58 NSCLC tissues and 58 adjacent tissues by immunohistochemistry. The relationship between FIGNL1, clinical pathological characteristics and disease-free survival was retrospectively analyzed. Gene ontology was used to analyze the biological process mainly involving FIGNL1, and STRING online constructed its protein interaction network and screened the key genes (hub genes).

RESULTS

The Cancer Genome Atlas showed that FIGNL1mRNA was higher in 1018 NSCLC tissues than in 111 adjacent tissues (P < 0.05). In the dataset "GSE157692," FIGNL1mRNA was higher in cisplatin-resistant cell lines (P = 3.80e-05). The hub genes in FIGNL1 and HRR directions are RAD51 and CCDC36. Immunohistochemistry showed that the FIGNL1 protein in 58 NSCLC tissues was higher than that in 58 adjacent tissues (P < 0.01). FIGNL1 is associated with gender, histopathological type, and nerve invasion in NSCLC. The disease-free survival in NSCLC patients with high FIGNL1 expression was shorter (P = 0.032).

CONCLUSION

FIGNL1 is associated with poor prognosis in NSCLC, and cisplatin resistance may be involved. These observations provide a clinical basis for exploring FIGNL1 as a potential biomarker for cisplatin resistance in NSCLC.

The endocytic pathway of Pt nanoclusters and their induced apoptosis of A549 and A549/Cis cells through c-Myc/p53 and Bcl-2/caspase-3 signaling pathways

In recent years, multifunctional platinum nanoclusters (Pt-NCs) as new Pt-based anti-cancer drugs exhibit a promising therapeutic efficiency for several cancer diseases, especially for human pulmonary carcinoma. However, the endocytosis behaviors (like uptake pathway, etc.) and induced apoptosis mechanism of Pt-NCs for drug-resistant non-small cell lung cancer (NSCLC), are still inconclusive. In this research, we explored the endocytic pathway of Pt-NCs in both typical NSCLC A549 cells and cisplatin-resistant A549/Cis cells through qualitative confocal laser scanning microscope (CLSM) measurement and quantitative flow cytometry (FCM) and inductive coupled plasma-optical emission spectroscopy (ICP-OES) analysis, by the means of introducing the specific inhibitors which impede the classical ways of endocytosis. It was found that Pt-NCs dominatingly entered A549 cells via caveolin-mediated endocytosis as well as A549/Cis cells through micropinocytosis approach. Pt-NCs possessed an excellent inhibitory effect on the cell proliferation, migration and invasion, which the cell activity of A549 cells reduced to 14% and that of A549/Cis cells went down about four fifths. Moreover, Pt-NCs treatment increased caspase-3 protein levels and downregulated the expression of c-Myc and Bcl-2, proving the Pt-NCs-induced apoptosis of NSCLC cells was related to c-Myc/p53 and Bcl-2/caspase-3 signal pathways. These results demonstrate the explicit uptake pathway and apoptotic signaling pathway of Pt-NCs for NSCLC, which provides an in-depth and reasonable theoretical basis for the development of new Pt-NCs-based chemotherapeutics in future clinical practice.

Bioinformatics analysis of mRNA and miRNA microarray to identify the key miRNA-mRNA pairs in cisplatin-resistant ovarian cancer

Background

Ovarian cancer (OC) is a gynecological malignancy with the highest mortality rate. Cisplatin (DDP) based chemotherapy is a standard strategy for ovarian cancer. Despite good response rates for initial chemotherapy, almost 80% of the patients treated with DDP based chemotherapy will experience recurrence due to drug-resistant, which will ultimately result in fatality. The aim of the present study was to examine the pathogenesis and potential molecular markers of cisplatin-resistant OC by studying the differential expression of mRNAs and miRNAs between cisplatin resistant OC cell lines and normal cell lines.

Methods

Two mRNA datasets (GSE58470 and GSE45553) and two miRNA sequence datasets (GSE58469 and GSE148251) were downloaded from the Gene expression omnibus (GEO) database. Differentially expressed genes (DEGs) and differentially expressed miRNAs (DEMs) were screened by the NetworkAnalyst. Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were conducted to analyze the biological functions of DEGs. The protein-protein interaction network was constructed using STRING and Cytoscape software to identify the molecular mechanisms of key signaling pathways and cellular activities. FunRich and MiRNATip databases were used to identify the target genes of the DEMs.

Results

A total of 380 DEGs, and 5 DEMs were identified. Protein–protein interaction (PPI) network of DEGs containing 379 nodes and 1049 edges was constructed, and 4 key modules and 24 hub genes related to cisplatin-resistant OC were screened. Two hundred ninety-nine target genes of the 5 DEMs were found out. Subsequently, one of these 299 target genes (UBB) belonging to the hub genes of GSE58470 and GSE45553 was identified by MCODE and CytoHubba,which was regulated by one miRNA (mir-454).

Conclusions

One miRNA–mRNA regulatory pairs (mir-454-UBB) was established. Taken together, our study provided evidence concerning the alteration genes involved in cisplatin-resistant OC, which will help to unravel the mechanisms underlying drug resistant.