Curcumin/L-OHP co-loaded HAP for cGAS-STING pathway activation to enhance the natural immune response in colorectal cancer.

Insufficient immune cell infiltration into the tumor microenvironment (TME) greatly compromises the clinical application of immune-checkpoint inhibitors (ICIs)-based immunotherapy. Recent findings have shown that activation of the cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING) pathway can enhance natural immunity and increase lymphocyte infiltration into the TME, which presents a promising strategy for cancer immunotherapy. In this study, we constructed hydroxyapatite nanoparticles co-loaded with curcumin and L-oxaliplatin (Cur/L-OHP@HAP NPs). We analyzed the particle-size distribution, zeta potential, spectral characteristics (Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, ultraviolet-visible spectroscopy), and drug-release properties of the Cur/L-OHP@HAP NPs. The cellular uptake of the Cur/L-OHP@HAP NPs detected by flow cytometry and confocal laser-scanning microscopy. We comprehensively evaluated the anti-tumor properties and immune-activating effects of the NPs, both in vitro and in vivo. Physicochemical characterizations demonstrated that the Cur/L-OHP@HAP NPs were successfully synthesized and were capable of pH-dependent drug release. Notably, the Cur/L-OHP@HAP NPs efficiently entered cancer cells, after which the released L-OHP induced nuclear DNA (nDNA) damage to some extent. HAP promoted the release of intracellular Ca2+ stores in cancer cells, and curcumin inhibited Ca2+ efflux, resulting in intracellular Ca2+ overload and the release of mitochondrial DNA (mtDNA). Damage to both nDNA and mtDNA greatly stimulated the cGAS-STING pathway, thereby activating natural immunity, accompanied by immune cell recruitment to the TME. In summary, the Cur/L-OHP@HAP NPs show good prospects for improving cancer immunotherapy.

LncRNA NORAD mediates KMT2D expression by targeting miR-204-5p and affects the growth of gastric cancer.

Background: Long non-coding ribonucleic acids (lncRNAs) are a class of non-coding RNAs implicated in the development of many malignancies, including gastric cancer (GC). In this study, we investigated the functions and molecular mechanisms of non-coding RNA activated by deoxyribonucleic acid damage (NORAD) in GC. Methods: NORAD expression at the messenger RNA levels was determined by quantitative reverse transcriptase (RT)-polymerase chain reaction assays. Cell proliferation, migration, and invasion were detected by Cell Counting Kit-8 assays, in-vivo tumor formation assays, and Transwell assays. Cell-cycle distribution was detected by a flow cytometry analysis. NORAD location was detected by nucleocytoplasmic fractionation assays. The interaction between NORAD and the microRNA-204-5p (miR-204-5p)/Lysine Methyltransferase 2D (KMT2D) axis was verified by dual-luciferase reporter gene assays and RNA binding protein immunoprecipitation (RIP) assays. Western blot was used to study the phosphatase and tensin homolog (PTEN)/phosphoinositide 3-kinases (PI3K)/protein kinase B (AKT) signaling pathway. Results: NORAD was upregulated in the GC tissues and cell lines. The silencing of NORAD repressed cell proliferation and the Growth 2 (G2)/Mitosis (M) cell-cycle transition in GC. NORAD also regulated KMT2D expression by targeting miR-204-5p and mediated PTEN/PI3K/AKT signaling in GC. Conclusions: We found that NORAD acts as an oncogene in GC. Our findings might provide a novel therapeutic target for GC.

Role of CircRNAs_100395 in Proliferation and Metastases of Liver Cancer.

BACKGROUND Circular RNAs (circRNAs) are a kind of noncoding RNA with high cancer-specific expression, and great potential in regulating tumorigenesis. Among these, circRNA_100395 (circ_100395) has been reported to be downregulated in lung cancer, and participates in the process of tumor cell proliferation and metastasis. However, its expression and function in liver cancer remain unknown. MATERIAL AND METHODS Quantitative real-time polymerase chain reaction (RT-qPCR) was used to evaluate the expression level of circ_100395 and microRNAs-1228 (miR-1228) in liver cancer samples and the adjacent non-tumor tissues. Cell proliferation, apoptosis, invasion, migration, and epithelial-mesenchymal transition (EMT) pathway of circ_100395 upregulated cells were analyzed using a Cell Counting Kit-8 (CCK-8), flow cytometry, Transwell assay, and Western blot analysis. RESULTS We found that circ_100395 was downregulated in cancerous liver tissues relative to the adjacent normal tissues. The overexpression of circ_100395 was negatively associated with tumor differentiation, microvascular invasion, and portal vein tumor thrombosis. However, patients with higher circ_10039 expression tended to have better postoperative disease-free survival time. Moreover, upregulation of circ_100395 in liver cancer cells inhibited cell proliferation, induced apoptosis, then silenced the EMT pathway and reduced migration and invasion abilities, while this anti-tumor effect was significantly reversed by the downstream target, miR-1228. CONCLUSIONS circ_100395 appears to be a promising therapeutic target for liver cancer.

Next-Generation Sequencing Analysis of mRNA Profile in Cisplatin-Resistant Gastric Cancer Cell Line SGC7901.

BACKGROUND Cisplatin-resistant gastric cancer (GC) occurs in patients with GC treated with cisplatin-based chemotherapy, which results in disease progression and early recurrence during the treatment. MATERIAL AND METHODS To understand the initiation and developmental mechanism underlying cisplatin-resistant GC, we developed cisplatin-resistant SGC7901 cells (SGC7901/DDP) from the parental cells (SGC7901/S) by continuous exposure to increasing concentrations of cisplatin and subjected these 2 cell lines to RNA sequencing analysis. The data were verified by quantitative polymerase chain reaction and their functional role was evaluated by cell counting kit 8 assay and cell apoptosis and cell cycle flow cytometric analysis. Bioinformatics analysis was performed to classify the differentially-expressed genes (DEGs) involved in the development of cisplatin resistance. RESULTS In comparison with SGC7901/S cells, SGC7901/DDP cells showed a total of 3165 DEGs (2014 upregulated and 1151 downregulated, fold change ≥2, and adjusted P value <0.001). qRT-PCR confirmed the reliability of the RNA sequencing results. Depletion of the top 5 upregulated mRNAs reversed the resistant index, increased apoptotic SGC7901/DDP cells, and arrested the cells at G2/M phase. Gene ontology analysis revealed that the DEGs mainly regulate metabolic process, immune system, locomotion, cell adhesion, cell growth, cell death, cytoskeleton organization, cell binding, signal transducing activity, and antioxidant activity. Kyoto Encyclopedia of Genes and Genomes analysis showed that the DEGs were mainly involved in the PI3K-Akt signaling pathway, Rap1 signaling pathway, proteoglycans in cancer, regulation of actin cytoskeleton, and pathways in cancer. CONCLUSIONS The present study is the first to interrogate mRNAs profiles in human GC cells with cisplatin resistance using RNA sequencing, which may assist in discovering potential therapeutic targets for cisplatin-resistant GC patients.

Sophocarpine inhibits the growth of gastric cancer cells via autophagy and apoptosis.

Sophocarpine is one of the major ingredients of Sophorae flavescentis which could inhibits many kinds of cancers. However, the effect of sophocarpine on gastric cancer (GC) and the mechanism involved remain unknown. The present study aims to explore the effects of the sophocarpine on the proliferation and apoptosis of GC cells and elucidates the relevant molecular mechanisms. After treatment with sophocarpine, GC cells were evaluated on their proliferation, autophagy, cell cycle progress and apoptosis. The protein levels of LC3-I, LC3-II, Beclin, p62, PTEN, PI3K, p53, Bax, Bcl-2, AKT and p-AKT were detected by western blot. Sophocarpine inhibited the proliferation of GC cells both in vitro and in vivo dose-dependently. Sophocarpine not only caused cell apoptosis and cell cycle arrest in G0/G1 phase but also induced cell autophagy. Moreover, sophocarpine dose-dependently suppressed PI3K/AKT signaling pathway and activated apoptosis in gastric cancer cells. Thus, sophocarpine significantly inhibited the growth of GC cells through multiple mechanisms such as induction of autophagy, activation of cell apoptosis and down-regulation of cell survival signaling pathway.

Clinical significance of SLP-2 in hepatocellular carcinoma tissues and its regulation in cancer cell proliferation, migration, and EMT.

Stomatin-like protein 2 (SLP-2) gene was significantly upregulated in a variety of tumor tissues and found to be involved in proliferation and metastasis. However, its functional role in hepatocellular carcinoma (HCC) remains unknown. Our study was to investigate the function of SLP-2 in cell proliferation, migration, invasion, cell apoptosis, and the process of epithelial-mesenchymal transition (EMT) in HCC. SLP-2 mRNA and protein expression in HCC were assessed by qRT-PCR and immunohistochemical staining. In vitro, we determined cell proliferation, migration, invasion, and cell apoptosis by CCK-8, transwell, and flow cytometry assays, respectively. SLP-2 was found to be upregulated at both mRNA and protein levels in HCC tissues, and its aberrant overexpression was linked with poor prognosis in patients with HCC. SLP-2 downregulation by siRNAs significantly suppressed cell proliferation, migration, invasion, anti-apoptosis abilities, and inhibited EMT process in vitro. In conclusion, the present study demonstrated the overexpression of SLP-2 in HCC tissues for the first time. As an effective regulator involved in cell proliferation, migration, invasion, cell apoptosis, and EMT, SLP-2 could be a novel therapeutic target for patients with HCC who express high levels of SLP-2.