DPY30 Promotes Proliferation and Cell Cycle Progression of Colorectal Cancer Cells via Mediating H3K4 Trimethylation.

DPY30, a core subunit of the SET1/MLL histone H3K4 methyltransferase complexes, plays an important role in diverse biological functions through the epigenetic regulation of gene transcription, especially in cancer development. However, its involvement in human colorectal carcinoma (CRC) has not been elucidated yet. Here we demonstrated that DPY30 was overexpressed in CRC tissues, and significantly associated with pathological grading, tumor size, TNM stage, and tumor location. Furthermore, DPY30 knockdown remarkably suppressed the CRC cell proliferation through downregulation of PCNA and Ki67 in vitro and in vivo, simultaneously induced cell cycle arrest at S phase by downregulating Cyclin A2. In the mechanistic study, RNA-Seq analysis revealed that enriched gene ontology of cell proliferation and cell growth was significantly affected. And ChIP result indicated that DPY30 knockdown inhibited H3 lysine 4 trimethylation (H3K4me3) and attenuated interactions between H3K4me3 with PCNA, Ki67 and cyclin A2 respectively, which led to the decrease of H3K4me3 establishment on their promoter regions. Taken together, our results demonstrate overexpression of DPY30 promotes CRC cell proliferation and cell cycle progression by facilitating the transcription of PCNA, Ki67 and cyclin A2 via mediating H3K4me3. It suggests that DPY30 may serve as a potential therapeutic molecular target for CRC.

Retinoic Acid Receptor Gamma (RARγ) Promotes Cartilage Destruction through Positive Feedback Activation of NF-κB Pathway in Human Osteoarthritis.

Osteoarthritis (OA) is a severe inflammation-related disease which leads to cartilage destruction. The retinoic acid receptor gamma (RARγ) has been indicated to be involved in many inflammation processes. However, the role and mechanism of RARγ in cartilage destruction caused by inflammation in OA are still unknown. Here, we demonstrated that the RARγ was highly expressed in chondrocytes of OA patients compared with healthy people and was positively correlated with the damage degree of cartilage in OA. Cytokine TNF-α promoted the transcription and expression of RARγ through activating the NF-κB pathway in OA cartilage. In addition, the overexpression of RARγ resulted in the upregulation of matrix degradation and inflammation associated genes and downregulation of differentiation and collagen production genes in human normal chondrocyte C28/I2 cells. Mechanistically, overexpression of RARγ could increase the level of p-IκBα and p-P65 to regulate the expression of downstream genes. RARγ and IκBα also could interact with each other and had the same localization in C28/I2 cells. Moreover, the SD rats OA model induced by monosodium iodoacetate indicated that CD437 (RARγ agonist) and TNF-α accelerated the OA progression, including more severe cartilage layer destruction, larger knee joint diameter, and higher serum ALP levels, while LY2955303 (RARγ inhibitor) showed the opposite result. RARγ was also highly expressed in OA group and even higher in TNF-α group. In conclusion, RARγ/NF-κB positive feedback loop was activated by TNF-α in chondrocyte to promote cartilage destruction. Our data not only propose a novel and precise molecular mechanism for OA disease but also provide a prospective strategy for the treatment.

Trilobolide-6-O-isobutyrate exerts anti-tumor effects on cholangiocarcinoma cells through inhibiting JAK/STAT3 signaling pathway.

Trilobolide-6-O-isobutyrate exhibits significant antitumor effects on cholangiocarcinoma (CCA) cells by effectively inhibiting the JAK/STAT3 signaling pathway. This study aims to investigate the mechanisms underlying the antitumor properties of trilobolide-6-O-isobutyrate, and to explore its potential as a therapeutic agent for CCA. This study illustrates that trilobolide-6-O-isobutyrate efficiently suppresses CCA cell proliferation in a dose- and time-dependent manner. Furthermore, trilobolide-6-O-isobutyrate stimulates the production of reactive oxygen species, leading to oxidative stress and initiation of apoptosis via the activation of the mitochondrial pathway. Data from xenograft tumor assays in nude mice confirms that TBB inhibits tumor growth, and that there are no obvious toxic effects or side effects in vivo. Mechanistically, trilobolide-6-O-isobutyrate exerts antitumor effects by inhibiting STAT3 transcriptional activation, reducing PCNA and Bcl-2 expression, and increasing P21 expression. These findings emphasizes the potential of trilobolide-6-O-isobutyrate as a promising therapeutic candidate for the treatment of CCA.

[Antitumor effect of capsaicin on colorectal carcinoma xenograft in nude mice].

OBJECTIVE: To evaluate the effect of capsaicin on nude mice xenografted with colorectal carcinoma cells, and to explore its mechanism of action. METHODS: A nude mouse model of colorectal cancer was established by subcutaneous inoculation of human colorectal carcinoma HT-29 cells. Terminal deoxynucleotidyl transferase-mediated nicked labeling assay (TUNEL) was undertaken to detect the cell proliferation and apoptosis in the xenograft tissue in nude mice. Immunohistochemical (IHC) staining and Western blot were used to detect the expression of HSP27, Cyt-C and active caspase-3. RESULTS: The tumor growth of the groups C10 and C20 was significantly slower than that of the group NS. The integrated optical density (IOD) of both the group C5 (2532.14 ± 578.11) and group C10 (6364.03 ± 1137.98) was significantly higher than that of the group NS (760.12 ± 238.05), (P < 0.05). The integrated optical density (IOD) of the group C20 was (15743.96 ± 1855.95), significantly higher than that of the groups C10, C5 and NS (all were P < 0.01). Immunohistochemistry showed that the cytoplasmic expression of HSP27 was strongly positive in the group NS, and significantly reduced with the increasing dose of capsaicin in the treated groups. The expression of active caspase-3 and Cyt-C in the group NS was weakly positive, and was significantly increased with the increasing dose of capsaicin in the groups C5 and C10 (P < 0.05), and the expression of active caspase-3 and Cyt-C of the group C20 was significantly higher than that of the groups C5, C10 and NS (P < 0.01). Western blot analysis showed that both the expressions of HSP27 of the group C5 (0.73 ± 0.05) and the group C10 (0.41 ± 0.03) were significantly lower than that of the group NS (P < 0.05). The expression of HSP27 of the group C20 (0.22 ± 0.06) was significantly lower than that of the groups C5, C10 and NS (P < 0.01). The expressions of active-caspase-3 and Cyt-C in the group C5 were (2.57 ± 0.34) and (2.03 ± 0.38), significantly higher than those of the group NS (P < 0.05). The expressions of active-caspase-3 and Cyt-C in the group C10 were (4.23 ± 0.45) and (3.13 ± 0.44), also significantly higher than those of the group NS (P < 0.05). The expressions of active-caspase-3 and Cyt-C in the group C20 were (5.78 ± 0.48) and (4.92 ± 0.52), significantly higher than those of the group C5, C10 and NS (P < 0.01). TUNEL analysis showed that there was a significant difference of cell apoptosis in comparison of each two groups. The higher dose of capsaicin was used, the more apoptosis was observed. CONCLUSIONS: Capsaicin can significantly inhibit the tumor growth and induce cell apoptosis in the colorectal carcinoma xenograft in nude mice. Its mechanism of action is possibly related with the down-regulation of HSP27 expression and up-regulation of expression of active caspase-3 and Cyt-C in the colorectal carcinoma xenograft in nude mice.

HPLC-DAD method for comprehensive quality control of Semen Strychni.

CONTEXT: Semen Strychni is the seed of Strychnos nux-vomica L. (Loganiaceae). Its quality control procedure remains an issue since previous reports only focused on Strychnos alkaloids. To the best of our knowledge, chlorogenic acid (a phenolic acid) and loganin (an iridoid glycoside) are selected for the first time as marker constituents of quality control for Semen Strychni because of their bioactive activity correlating with therapeutic effects. OBJECTIVE: This study aimed to develop a simple and comprehensive quantity control method for Semen Strychni. MATERIALS AND METHODS: The optimal ultrasonic extraction procedure was carried out for 45 min using 50% aqueous methanol with 1% formic acid. The satisfactory chromatographic separation was achieved on an Ultimate LP-C18 column with gradient elution using acetonitrile and water containing 30 mmol/L ammonium acetate and 1% formic acid. The high performance liquid chromatography method with diode array detector was validated for linearity, limit of detection and quantification (LOQ), precision, repeatability, accuracy and stability. RESULTS: All the calibration curves showed good linearity (r(2) ≥ 0.999). The LOQ values for chlorogenic acid, loganin, strychnine, brucine, strychnine N-oxide and brucine N-oxide were 0.54, 0.83, 0.48, 0.50, 0.52 and 0.54 µg/mL, respectively. The method was reproducible with good accuracy in the range 95.6-104.4% and relative standard deviation (RSD) values less than 4.55%. The method was then applied to determine the components of the seed coat, seed leaf, endosperm and whole seed of Semen Strychni. CONCLUSION: This newly established method is validated as a simple and practical tool for authentication and quality control of Semen Strychni.

Boosting Doxorubicin-Induced Mitochondria Apoptosis for the Monodrug-Mediated Combination of Chemotherapy and Chemodynamic Therapy.

Doxorubicin (Dox)-mediated generation of reactive oxygen radicals (ROS) for mitochondrial apoptosis is identified as a new cytotoxic mechanism in addition to the well-established one via nuclear DNA replication interference. However, this mechanism contributes far less than the latter to Dox therapy. This newly identified pathway to make Dox therapy function like the combination of chemodynamic therapy (CDT) and chemotherapy-mediated by Dox alone would be amplified. One-pot nanoconstruction (HEBD) is fabricated based on the chemical reactions driven assemblies among epigallocatechin gallate (EGCG), buthionine sulfoximine (BSO) and formaldehyde in aqueous mediums followed by Dox adsorption. Acid tumor microenvironments allow the liberation of EGCG, BSO, and Dox due to the breakage of Schiff base bonds. EGCG component in HEBD is responsible for targeting mitochondria and disrupting mitochondrial electron transport chain (mETC) to compel electrons leakage in favor of their capture by Dox to produce more ROS. EGCG-induced mETC disruption results in mitochondrial respiration inhibition with alleviated hypoxia in tumor cells while BSO inhibits glutathione biosynthesis to protect ROS from redox depletion, further boosting Dox-induced CDT. This strategy of amplifying CDT pathway for the Dox-mediated combined therapy could largely improve antitumor effect, extend lifespan of tumor-bearing mice, reduce risks of cardiotoxicity and metastasis.

Light-Triggered Nitric Oxide Nanogenerator with High l-Arginine Loading for Synergistic Photodynamic/Gas/Photothermal Therapy.

The development of nanomedicines that combine photothermal therapy (PTT) with photodynamic therapy (PDT) is considered promising for cancer treatment, but still faces the challenge of enhancing tumoricidal efficiency. Fortunately, apart from the well-acknowledged effect on direct tumor cell-killing, nitric oxide (NO) is also considered to be effective for the enhancement of both PTT and PDT. However, both the low loading efficiency of NO precursor and the short half-life time and diffusion distance of NO hamper the synergistic therapeutic efficacy of NO. Taking the aforementioned factors into account, a mitochondria-targeted nitric oxide nanogenerator, EArgFe@Ce6, is constructed to achieve high loading of the NO donor l-Arginine (l-Arg) for synergistic photodynamic/gas/photothermal therapy upon single 660 nm light irradiation. The coordination of epigallocatechin gallate (EGCG) and ferric ions (Fe3+ ) provides EArgFe@Ce6 supreme photothermal capability to perform low-temperature PTT (mPTT). EGCG endows EArgFe@Ce6 with mitochondria-targeting capability and meanwhile favors hypoxia alleviation for enhanced PDT. The PDT-produced massive reactive oxygen species (ROS) further catalyzes l-Arg to generate a considerable amount of NO to perform gas therapy and sensitize both mPTT and PDT. In vitro and in vivo studies demonstrate that the synergistic photodynamic/gas/photothermal therapy triggered by single 660 nm light irradiation is highly effective for tumor treatments.

A Metal-Polyphenol-Based Oxygen Economizer and Fenton Reaction Amplifier for Self-Enhanced Synergistic Photothermal/Chemodynamic/Chemotherapy.

To overcome the limitations of doxorubicin (DOX) chemotherapy, nanomedicines that integrate additional photothermal therapy (PTT) and chemodynamic therapy (CDT) strategies are highlighted as promising alternatives for the treatment of malignant tumors. However, time-consuming preparation processes, biosafety concerns, and the bottlenecks of individual therapeutic modalities often limit the practical applications of this strategy. To address these issues, this work designs an oxygen economizer that additionally serves as a Fenton reaction amplifier through the simple assembly of epigallocatechin gallate (EGCG), pluronic F-127 (PF127), iron (III) ions, and doxorubicin (DOX) for the enhancement of synergistic PTT/CDT/chemotherapy. The resulting nanoformulation, EFPD, can target mitochondria and inhibit cell respiration to reduce O2 consumption, thus boosting DOX-mediated H2 O2 generation for enhanced CDT and simultaneously improving hypoxia-limited DOX chemotherapy efficacy. Moreover, the coordination between EGCG and Fe3+ provides EFPD with excellent photothermal conversion efficiencies (η = 34.7%) for PTT and photothermal-accelerated drug release. Experimental results indicate that EFPD-mediated synergistic enhancement of PTT/CDT/chemotherapy can achieve excellent therapeutic outcomes, including enhanced ablation of solid tumors, reduced metastasis and cardiotoxicity, and extended life spans.

RARγ promotes the invasion and metastasis of thyroid carcinoma by activating the JAK1-STAT3-CD24/MMPs axis.

The nuclear receptor superfamily RAR is generally considered to play a crucial role in the development of tumors by regulating the transcription of target genes. Nevertheless, whether RARγ performs tumor-promoting or tumor-suppressing functions and its specific mechanism in thyroid carcinoma (TC) remain unknown. Here, our study demonstrated that RARγ was abnormally overexpressed in TC tissues compared with normal thyroid tissues. Moreover, RARγ expression was remarkably correlated with cell phenotypes such as cell proliferation, migration and invasion. Mechanistically, RARγ knockdown effectively decreased the phosphorylation levels of JAK1 and STAT3, leading to decreased expression of the membrane protein CD24. In a coculture system, TC cells with high levels of CD24 in the membrane were more likely to escape phagocytosis by macrophages via the combination of CD24 with the inhibitory receptor Siglec-10 in the membrane of macrophages. In contrast, the ability of macrophages to engulf TC cells was notably elevated through exogenous addition of CD24 antibody. Collectively, our study revealed a previously undiscovered molecular mechanism of RARγ in promoting the development of TC, shedding light on RARγ as a promising therapeutic target for TC.

[Comparison of effect between early and delayed in primary intramedullary nailing combined with locked plate fixation for the treatment of multi-segments tibial fractures of type].

OBJECTIVE: To compare the clinical results of early and delayed intramedullary nailing and locked plating for the treatment of multi-segments tibial fractures of type AO/ASIF-42C2. METHODS: Between January 2010 and January 2013,45 patients with multi-segments closed tibial fractures of AO/ASIF-42C2 were treated by early primary intramedullary nailing and locked plating in 20 cases as early group and delayed in 25 cases as delayed group. In early group,20 cases included 13 males and 7 females with an average age of (37.9±14.3) years old ranging from 20 to 56 years;according to soft tissue injury Tscherne classification, 8 fractures were frade I,12 were grade II. In delayed group, 25 cases included 17 males and 8 females with an average age of (38.7±17.2) years old ranging from 24 to 55 years,4 fractures were grade I ,19 were grade II ,2 were grade III. The operative time, blood loss, hospital stay,fracture healing time and complications were recorded. At final follow-up, the Johner-Wruhs score were used to evaluate functional efficacy, and the posterior-anterior and lateral X-ray to evaluate fracture reduction and alignment. RESULTS: All the patients were followed up for (12.5±2.5) months in early group and (13.2±2.8) months in delayed group (P>0.05). No wounds infections were happened. At the last follow-up, the mean range of knee joint was 10°-0°-120°. According to Johner-Wruhs scoring,there were 15 cases in excellent,3 in good,fair in 2 in early group; 21 in excellent,2 in good,2 in fair. The average operative time,blood loss had no significant differences between two groups (P>0.05), but hospital stay in early group was significantly shorter than those in delayed group(P<0.05). Average fracture healing time of early group and delayed group were (5.3±2.6) months and (6.0±2.9) months, respectively (P>0.05). CONCLUSION: For multi-segments tibial fractures of type AO/ASIF-42C2 with preoperative minor soft tissue injuries lighter of Tscherne grade I or II, early primary intramedullary nailing and locked plating does not significantly increase the postoperative incidence of soft tissue complications for patients. The early and delayed primary intramedullary nailing and locked plating for treatment of AO/ASIF-42C2 proximal third tibial fractures can get similar curative effect.

[Effect of gastric bypass surgery on mRNA expression level of hepatic phosphoenolpyruvate carboxykinase in type 2 diabetic Goto-Kakizaki rats].

OBJECTIVE: To investigate the effects of gastric bypass surgery(GBP) on hepatic phosphoenolpyruvate carboxykinase(PEPCK) mRNA expression in type 2 diabetic Goto-Kakizaki rats. METHODS: Male GK rats were randomized into three groups: gastric bypass surgery(n=10), sham operation with diet restriction(n=10), and sham operation alone(n=10). Liver specimens of GK rats were collected during the intraoperative period for self-control study and 8 weeks after surgery. Fasting blood glucose, food intake, and body weight were recorded before surgery and 1, 2, 4, 8 weeks after surgery. The expression of PEPCK mRNA was measured by real-time PCR. RESULTS: The fasting plasma glucose level decreased from(17.6±2.1) mmol/L before surgery to(7.5±0.9) mmol/L 8 weeks after surgery in GBP group. The level of PEPCK mRNA decreased from 1.08±0.38 before surgery to 0.41±0.10 8 weeks after surgery, significantly lower than that in sham operation alone group(1.04±0.12)(P<0.01). The level of PEPCK mRNA in diet restriction group increased from 1.15±0.16 before surgery to 2.54±0.82 8 weeks after surgery(P<0.01). The expression of PEPCK mRNA in diet restriction was significantly higher than that in CBP group(P<0.01). CONCLUSIONS: GBP can significantly improve hyperglycemia in type 2 diabetic GK rat models, which may be associated with the decrease of hepatic PEPCK mRNA level.