Exosome-Transmitted miR-224-5p Promotes Colorectal Cancer Cell Proliferation via Targeting ULK2 in p53-Dependent Manner.

Objective: To investigate the role and molecular mechanism of exosomal miR-224-5p in colorectal cancer (CRC). Methods: The miR-224-5p expression in CRC patient tissues and cell-derived exosomes was measured by laser capture microdissection and qRT-PCR, respectively. Dual-luciferase reporter gene assay was used to determine the target gene of miR-224-5p. The protein expressions of p53 and unc-51 like kinase 2 (ULK2) in CRC cells were detected by western blot. Flow cytometry was used to detect cell cycle and apoptosis. Cell proliferation was measured by CCK8 and EdU assay. Results: The miR-224-5p expression was upregulated in CRC tissues and increased progressively with the rise of CRC stage. CRC cells secreted extracellular miR-224-5p mainly in an exosome-dependent manner, and then miR-224-5p could be transferred to surrounding tumor cells to regulate cell proliferation in the form of autocrine or paracrine. Moreover, ULK2 was characterized as a direct target of miR-224-5p and was downregulated in CRC tissues. Interestingly, ULK2 inhibited CRC cell proliferation in a p53-dependent manner. Furthermore, exosome-derived miR-224-5p partially reversed the proliferation regulation of ULK2 on CRC cells. Conclusion: Our findings demonstrate that exosome-transmitted miR-224-5p promotes p53-dependent cell proliferation by targeting ULK2 in CRC, which may offer promising targets for CRC prevention and therapy.

[Clinical analysis of denture-related oral mucosal lesions in 185 patients with removable denture].

PURPOSE: To investigate the category and prevalence rate of denture-related oral mucosal lesions (DML) in 185 patients with removable denture and analyze the influencing factors. METHODS: A total of 185 patients with removable denture who visited the department of stomatology of our hospital from October 2015 to June 2018 were investigated by questionnaire. DML types and locations were recorded in detail, and patients were followed up after treatment. Based on the data of this study, the differences of DML reports in other regions of China were analyzed by comparing the results searched from databases. SPSS 17.0 software package was used for statistical analysis. RESULTS: In this study, the DML prevalence rate was 42.7%, significantly higher in male patients than in female patients (54.17% vs 35.40%, P<0.05). DML was more common in complete denture wearers than that in partial denture wearers (66.67% vs 31.20%, P<0.05). The categories of DML were as followed (prevalence rate from high to low): denture stomatitis (54.43%), traumatic ulcer (34.18%), inflammatory hyperplasia (6.33%), and angular cheilitis (5.06%). CONCLUSIONS: DML is affected by multiple factors. Among them, denture related factors include denture type, denture wearing time, denture lasting time and cleaning method. DML is more influenced by the type of denture than the wearing time. Gender, ethnicity and systemic diseases may affect the prevalence of DML, but further studies are needed. The results of domestic studies in various regions cannot objectively reflect the current prevalence rate of DML, thus a multi-center epidemiological investigation is needed.

Optimization of process parameters of extraction of amentoflavone, quercetin and ginkgetin from Taxus chinensis using supercritical CO2 plus co-solvent.

The effects of extraction time, temperature, pressure and different concentration of ethanol and their interactions on the yields of amentoflavone, quercetin and ginkgetin extracted from Taxus chinensis by supercritical CO2 were investigated by using a central composite design (CCD). An CCD experimental design with four factors and five levels was used to optimize the extraction parameters. Ultra performance liquid chromatography (UPLC) was used to analyze the content of the tree components in the extracts. Experimental results show that the main effects of factors and their interactions are significant on the yields (p < 0.05). The optimal extraction conditions were established for the three compounds: yield of 4.47 mg/g for amentoflavone at 48 °C, 25 MPa, 2.02 h and 78.5% ethanol, 3.73 mg/g for quercetin at 46 °C, 24 MPa, 2.3 h, 82% ethanol and 3.47 mg/g for ginkgetin at 48 °C, 20 MPa, 2.38 h, 82% ethanol, respectively.

Phytotoxicity of 4,8-dihydroxy-1-tetralone isolated from Carya cathayensis Sarg. to various plant species.

The aqueous extract from Carya cathayensis Sarg. exocarp was centrifuged, filtered, and separated into 11 elution fractions by X-5 macroporous resin chromatography. A phenolic compound, 4,8-dihydroxy-1-tetralone (4,8-DHT) was isolated from the fractions with the strongest phytotoxicity by bioassy-guided fractionation, and investigated for phytotoxicity on lettuce (Latuca sativa L.), radish (Raphanus sativus L.), cucumber (Cucumis sativus L.), onion (Allium cepa L.) and wheat (Triticum aestivum L.). The testing results showed that the treatment with 0.6 mM 4,8-DHT could significantly depress the germination vigor of lettuce and wheat, reduce the germination rate of lettuce and cucumber, and also inhibit radicle length, plumule length, and fresh weight of seedlings of lettuce and onion, but could significantly promote plumule length and fresh weight of seedlings of cucumber (p < 0.05). For the tested five plants, the 4,8-DHT was the most active to the seed germination and seedling growth of lettuce, indicating that the phytotoxicity of 4,8-DHT had the selectivity of dosage, action target (plant type) and content (seed germination or seedling growth).

[Inducing-apoptosis effect of brucine on human monocytic leukemia cell line THP-1 and its mechanism].

This study was aimed to investigate the inducing-apoptosis effect of brucine on human monocytic leukemia cell line THP-1 cells and its possible mechanism. The inhibition effect of brucine on growth of THP-1 cells was measured by CCK-8 method. Morphological changes of THP-1 cells treated with brucine was detected by acridine orange/ethidium bromide (AO/EB)double staining. Annexin-V/PI double labeling method was used to assay the apoptosis rate of THP-1 cells. The effect of brucine on THP-1 cell cycle distribution was detected by PI single staining. RT-PCR was used to detect the expression of BCL-2 and BAX. The results showed that the brucine could inhibit the THP-1 cell growth in concentration and time-dependent manners at the range of 50 to 400 µg/ml. The cells stained with AO/EB revealed that the brucine induced the nuclear chromatin condensation. After the THP-1 cells were treated with brucine of 400µg/ml for 48 hours, most nucleic were stained as orange-red, and condensed, displaying the late apoptotic cell morphology. Annexin-V/PI detection showed that brucine could induce apoptosis of THP-1 cells in a concentration-dependent manner. Compared with the control group, more cells in brucine-treated group were arrested at G0/G1 phase in a concentration-dependent manner. RT-PCR detection revealed that the expression of BCL-2 was down-regulated strikingly and BAX was up-regulated. It is concluded that brucine can efficiently inhibit cell growth and block THP-1 cells in G0/G1 phase. The mechanism of THP-1 cell apoptosis induced by brucine may be related to the inhibition of BCL-2 and activation of BAX.