Background: Recent studies have shown that circular RNA (circRNA) is rich in microRNA (miRNA) binding sites. We have previously demonstrated that the antidepressant effect of ketamine is related to the abnormal expression of various miRNAs in the brain. This study determined the expression profile of circRNAs in the hippocampus of rats treated with ketamine. Methods: The aberrantly expressed circRNAs in rat hippocampus after ketamine injection were analyzed by microarray chip, and we further validated these circRNAs by quantitative reverse-transcription PCR (qRT-PCR). The target genes of the different circRNAs were predicted using bioinformatic analyses, and the functions and signal pathways of these target genes were investigated by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses. Results: Microarray analysis showed that five circRNAs were aberrantly expressed in rat hippocampus after ketamine injection (fold change > 2.0, p < 0.05). The results from the qRT-PCR showed that one of the circRNAs was significantly increased (rno_circRNA_014900; fold change = 2.37; p = 0.03), while one was significantly reduced (rno_ circRNA_005442; fold change = 0.37; p = 0.01). We discovered a significant enrichment in several GO terms and pathways associated with depression. Conclusion: Our findings showed the abnormal expression of ketamine-induced hippocampal circRNAs in rats.

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Cell migration and metastasis greatly contribute to the progression of tumors. Secreted Protein and Rich in Cysteine （SPARC）, as a multi-faceted protein, is highly expressed in highly metastatic tumors while low or undetectable in less metastatic types with aberrant promoter methylation. In highly metastatic tumors, such as glioblastomas, melanoma, breast cancer and prostate cancer, SPARC promotes bone metastasis and epithelial-mesenchymal transition (EMT). In contrast, this protein acts as an anti-tumor factor in anti-angiogenesis, pro-apoptosis, cell proliferation inhibition and cell cycle arrest in less metastatic tumors, such as neuroblastoma, ovarian cancer, pancreatic cancer, colorectal cancer and gastric cancer. Here, we summarize and analyze the paradoxical role of SPARC in different tumors. We believe that further studies on truncated, alternative splicing variants and signal peptide of SPARC are required to elucidate the distinct effects. Most notably, SPARC variants probably play a crucial role in regulation of transforming growth factor beta (TGF-β) induced EMT. This review also provides strategies to target or use SPARC (full-length, truncated and splicing variants) for therapeutic purposes.

Abstract. Polyphyllins, a major component of Rhizoma paridis, have been extensively used in non-small cell lung cancer (NSCLC). The aim of the present study was to evaluate the effects of Paris saponin I (PSI) on a panel of gefitinib-resistant NSCLC cell lines and its inhibition of tumor growth in a nude mouse model. The MTT assay was used to assess growth inhibition. The cell cycle was analyzed using flow cytometry and apoptosis was assessed using Annexin V/propidium iodide staining. The morphology of the apoptotic cells was determined by transmission electron microscopy. The protein expression levels of B-cell lymphoma 2 (Bcl-2), Bcl-2-associated X protein (Bax) and caspase-3 were detected using western blot analysis. In addition, the glucose metabolism in tumor-bearing mice was evaluated using 18 F-fludeoxyglucose (FDG) micro-positron emission tomography imaging. The PSI-induced growth inhibition rate was observed to significantly increase in a time-and dose-dependent manner. Furthermore, PSI induced significant G2/M-phase arrest and apoptosis. The expression levels of Bcl-2 decreased, while those of Bax and caspase-3 increased following PSI treatment.18 F-FDG-uptake in the PSI treatment groups was significantly decreased compared with that in the control group in vivo. In conclusion, PSI is a potent antitumor agent that acts by inhibiting the proliferation of gefitinib-resistant cells, and has potential as a candidate for a natural drug for gefitinib-resistant therapy. PSI-induced apoptosis, which occurred via multiple pathways, including G2/M-phase arrest and upregulation of the Bax/Bcl-2 ratio and caspase-3 expression, ultimately led to cell death and tumor inhibition.

An injectable alginate hydrogel containing silk fibroin microspheres that can sustain the release of IGF-1 is prepared for the treatment of myocardial infarction.

Abstract. Rhizoma paridis is widely used for cancer therapy due to its potential involvement in the suppression of tumor growth. However, at present there is no clear explanation for the mechanism underlying the inhibitory effects of Rhizoma paridis combined with hyperthermia on tumor growth. The aim of the present study was to evaluate the effects of Paris saponin I (PSI) combined with hyperthermia on a variety of non-small cell lung cancer (NSCLC) cell lines. An MTT assay was used to determine the levels of growth inhibition. The cell cycle was analyzed using flow cytometry and cell apoptosis was analyzed with Annexin V/propidium iodide staining and the Hoechst assay. The morphology of cells during apoptosis was determined using a transmission electron microscope. The expression levels of B-cell lymphoma 2 (Bcl-2), Bcl-2-associated X protein (Bax) and caspase-3 proteins were detected using western blotting. The inhibition rates significantly increased with PSI in combination with hyperthermia at 43˚C. PSI with hyperthermia at 43˚C caused G2/M phase arrest and significantly induced apoptosis. The expression level of Bcl-2 decreased, while Bax expression increased following treatment with PSI with hyperthermia at 43˚C. In addition, the protein expression of caspase-3 was significantly enhanced. PSI combined with hyperthermia is a potent antitumor treatment through the inhibition of proliferation of NSCLC cells and may be developed as a new antitumor therapy. PSI combined with hyperthermia significantly induced apoptosis through a multi regulatory process involving G2/M arrest and regulation of Bax, Bcl-2 and caspase-3 expression, resulting in cell death and tumor inhibition.

No abstract

Ketamine has a rapid, obvious, and persistent antidepressant effect, but its underlying molecular mechanisms remain unknown. Recently, microRNAs (miRNAs) have emerged as important modulators of ketamine’s antidepressant effect. We investigated the alteration in miR-29b-3p in the brain of rats subjected to ketamine administration and chronic unpredictable mild stress (CUMS), and a sucrose preference test and forced swimming test were used to evaluate the rats’ depressive-like state. We used recombination adeno-associated virus (rAAV) or lentivirus-expressing miR-29b-3p to observe the change in metabotropic glutamate receptor 4 (GRM4). Cell culture and electrophysiological recordings were used to evaluate the function of miR-29b-3p. Ketamine dramatically increased miR-29b-3p expression in the prefrontal cortex of the normal rats. The dual luciferase reporter test confirmed that GRM4 was the target of miR-29b-3p. The miR-29b-3p levels were downregulated, while the GRM4 levels were upregulated in the prefrontal cortex of the depressive-like rats. The ketamine treatment increased miR-29b-3p expression and decreased GRM4 expression in the prefrontal cortex of the depressive-like rats and primary neurons. By overexpressing and silencing miR-29b-3p, we further validated that miR-29b-3p could negatively regulate GRM4. The silencing of miR-29b-3p suppressed the Ca2+ influx in the prefrontal cortex neurons. The miR-29b-3p overexpression contributed to cell survival, cytodendrite growth, increases in extracellular glutamate concentration, and cell apoptosis inhibition. The overexpression of miR-29b-3p by rAAV resulted in a noticeable relief of the depressive behaviors of the CUMS rats and a lower expression of GRM4. The miR-29b-3p/GRM4 pathway acts as a critical mediator of ketamine’s antidepressant effect in depressive-like rats and could be considered a potential therapeutic target for treating major depression disorder.