LncRNA MALAT1 promotes breast cancer progression and doxorubicin resistance via regulating miR-570-3p.

BACKGROUND: Metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) is a long non-coding RNA (lncRNA) that regulates disease progression in various types of cancers. The aim of this study was to explore the role of MALAT1 in breast cancer (BC) progression and doxorubicin resistance. METHODS: Real-time polymerase chain reaction (RT-PCR) was used to determine the expression of MALAT1 in BC tissues and cells; MTT and Transwell assay were used to detect the proliferation, migration and invasion of BC cells, respectively; drug resistance test was performed to assess the sensitivity of BC cells to doxorubicin; dual-luciferase reporter gene assay was conducted to verify the interaction between MALAT1 and miR-570-3p. RESULTS: MALAT1 was highly expressed in BC tissues compared with normal tissues adjacent to cancer as well as in BC cells. In addition, inhibition the expression of MALAT1 could significantly suppress the proliferation, migration and invasion of BC cells. Meanwhile, down-regulation of MALAT1 sensitized BC cells to doxorubicin. Moreover, bioinformatics analysis suggested that miR-570-3p was the potential downstream target of MALAT1. Dual-luciferase reporter gene assay confirmed that MALAT1 could directly target miR-570-3p. Additionally, miR-570-3p was lowly expressed in BC tissues and cells. Up-regulation of miR-570-3p not only significantly inhibited the proliferation, metastasis, and invasion of BC cells, but also increased the sensitivity of BC cells to doxorubicin. CONCLUSION: MALAT1 functions as a novel oncogenic lncRNA in regulating the progression and doxorubicin resistance of BC by targeting miR-570-3p.

Divergent effects of climate change on future groundwater availability in key mid-latitude aquifers.

Groundwater provides critical freshwater supply, particularly in dry regions where surface water availability is limited. Climate change impacts on GWS (groundwater storage) could affect the sustainability of freshwater resources. Here, we used a fully-coupled climate model to investigate GWS changes over seven critical aquifers identified as significantly distressed by satellite observations. We assessed the potential climate-driven impacts on GWS changes throughout the 21st century under the business-as-usual scenario (RCP8.5). Results show that the climate-driven impacts on GWS changes do not necessarily reflect the long-term trend in precipitation; instead, the trend may result from enhancement of evapotranspiration, and reduction in snowmelt, which collectively lead to divergent responses of GWS changes across different aquifers. Finally, we compare the climate-driven and anthropogenic pumping impacts. The reduction in GWS is mainly due to the combined impacts of over-pumping and climate effects; however, the contribution of pumping could easily far exceed the natural replenishment.

Protective effect of Ganoderma atrum polysaccharides in acute lung injury rats and its metabolomics.

The present study aimed to evaluate effect of Ganoderma atrum polysaccharide (PSG) on acute lung injury (ALI) rats and its mechanisms. Results showed that PSG exhibited protective effects against ALI by maintaining pulmonary histology, reducing levels of pro-inflammatory cytokines and NO both in serum and lung tissue. Moreover, this study further evaluated the metabolic effects of PSG based on UPLC-Triple-TOF/MS metabolomics analysis in rats. Compared with control group, LysoPC (18:2), LPA (18:1), taurocholic acid, L-histidine, and L-tryptophan were identified as metabolic biomarkers in serum of ALI group. Furthermore, biological pathways analysis demonstrated that histidine metabolism, nitrogen metabolism, tryptophan and part glycerophospholipids metabolism were notably modified by PSG treatment in ALI rats. Additionally, improved gut microbial metabolite short-chain fatty acids were found after intake of PSG in ALI rat. Altogether, PSG could control ALI-induced aberrant inflammation and its mechanisms were linked to inhibit release of pro-inflammatory mediators and reverse metabolic pathway disturbances.

Effects of a Ganoderma atrum polysaccharide against pancreatic damage in streptozotocin-induced diabetic mice.

This study aimed at exploring the role of a Ganoderma atrum polysaccharide (PSG-1) in pancreatic damage in streptozotocin (STZ)-induced type 1 diabetes mellitus (T1DM) mice. The results suggested that blood glucose was significantly increased in the STZ group in comparison with the control group. After 4 weeks of treatment with PSG-1 or metformin (MET), blood glucose levels in the PSG-1 and MET groups were apparently lower than in the STZ group, indicating that PSG-1 triggered hypoglycemic effects in vivo. Moreover, experiments demonstrated that PSG-1 markedly decreased apoptosis of islet cells by inhibiting the mitochondrial apoptotic pathway and activating the PI3K/Akt survival pathway. PSG-1 also exerted anti-inflammatory effects, as evidenced by the dramatically decreased levels of IL-1ß, TNF-α and INF-γ and restraint of the TLR4-dependent NF-κB signal pathway. Meanwhile, PSG-1 maintained homeostasis of redox systems by increasing the activities of anti-oxidant enzymes and decreasing the amount of malondialdehyde in the pancreas. Together, these data provide evidence that PSG-1 can be employed as an alternative dietary supplement to ameliorate T1DM.

Genome-wide identification and characterization of TCP transcription factor genes in upland cotton (Gossypium hirsutum).

TCP proteins are plant-specific transcription factors (TFs), and perform a variety of physiological functions in plant growth and development. In this study, 74 non-redundant TCP genes were identified in upland cotton (Gossypium hirsutum L.) genome. Cotton TCP family can be classified into two classes (class I and class II) that can be further divided into 11 types (groups) based on their motif composition. Quantitative RT-PCR analysis indicated that GhTCPs display different expression patterns in cotton tissues. The majority of these genes are preferentially or specifically expressed in cotton leaves, while some GhTCP genes are highly expressed in initiating fibers and/or elongating fibers of cotton. Yeast two-hybrid results indicated that GhTCPs can interact with each other to form homodimers or heterodimers. In addition, GhTCP14a and GhTCP22 can interact with some transcription factors which are involved in fiber development. These results lay solid foundation for further study on the functions of TCP genes during cotton fiber development.

Protection of the cochlear hair cells in adult C57BL/6J mice by T-type calcium channel blockers.

The aim of the present study was to investigate the protective effect of T-type calcium channel blockers against presbycusis, using a C57BL/6J mice model. The expression of three T-type calcium channel receptor subunits in the cochlea of 6-8-week-old C57BL/6J mice was evaluated using reverse transcription-quantitative polymerase chain reaction. The results confirmed that the three subunits were expressed in the cochlea. In addition, the capacity of T-type calcium channel blockers to protect the cochlear hair cells of 24-26-week-old C57BL/6J mice was investigated in mice treated with mibefradil, benidipine or saline for 4 weeks. Differences in hearing threshold were detected using auditory brainstem recording (ABR), while differences in amplitudes were measured using a distortion product otoacoustic emission (DPOAE) test. The ABR test results showed that the hearing threshold significantly decreased at 24 kHz in the mibefradil-treated and benidipine-treated groups compared with the saline-treated group. The DPOAE amplitudes in the mibefradil-treated group were increased compared with those in the saline-treated group at the F2 frequencies of 11.3 and 13.4 kHz. Furthermore, the DPOAE amplitudes in the benidipine-treated group were increased compared with those in the saline-treated group at an F2 frequency of 13.4 kHz. The loss of outer hair cells (OHCs) was not evident in the mibefradil-treated group; however, the stereocilia of the inner hair cells (IHCs) were disorganised and sparse. In summary, these results indicate that the administration of a T-type calcium channel blocker for four consecutive weeks may improve the hearing at 24 kHz of 24-26-week-old C57BL/6J mice. The function and morphology of the OHCs of the C57BL/6J mice were significantly altered by the administration of a T-type calcium channel blocker; however, the IHCs were unaffected.

Effect of T-type calcium channel blockers on spiral ganglion neurons of aged C57BL/6J mice.

To explore the expression levels of T-type calcium channel receptors in spiral ganglion neurons of C57BL/6J mice and the effect of T-type calcium channel blockers on the spiral ganglion neurons of 42-44-W C57BL/6J mice. We first quantified the subunits of T-type calcium channel blockers in the spiral ganglion neurons of C57BL/6J mice in three groups (6-8 W, 24-26 W, 42-44 W) according to age via RT-PCR. Next, we administered three drugs (zonisamide, felodipine, saline) to the 42-44-W C57BL/6J mice by gavage for four weeks. We observed the changes in the hearing threshold of 42-44-W C57BL/6J mice after treatment. Meanwhile, we measured the expression of calcium-binding proteins of spiral ganglion neurons after treatment. Our results showed that three receptors were expressed in the spiral ganglion neurons of C57BL/6J mice. The expression level of α1H was stronger than that of α1G and α1I. The expression levels of three receptors especially for α1G and α1H significantly decreased with age. The hearing threshold at 24 kHz was significantly decreased after zonisamide administration. No significant difference in the expression level of calbindin in spiral ganglion neurons was noted. Interestingly, the expression level of calmodulin in spiral ganglion neurons was lower in the zonisamide-treated groups than in the felodipine- and saline-treated group. We concluded that the administration of T-type calcium channel blocker for four consecutive weeks can improve the hearing by ameliorating calcium overload on spiral ganglion neurons of 42-44-W C57BL/6J mice.

Anti-angiogenic effect of the total flavonoids in Scutellaria barbata D. Don.

BACKGROUND: Angiogenesis is closely related to the growth, invasion and metastasis of tumors, also considered as the key target of anticancer therapy. Scutellaria barbata D. Don (S. barbata), a traditional Chinese medicine, is being used to treat various diseases, including cancer. However, the antitumor molecular mechanism of S. barbata was still unclear. This study aimed to investigate the inhibitory effects of the total flavones in S. barbata (TF-SB) on angiogenesis. METHODS: Human umbilical vein endothelial cells (HUVECs) were treated with various concentrations of TF-SB. Cell viability was examined using the MTT assay. The scratch assay was used to detect the migration of HUVECs after treatment with TF-SB. The ability of HUVECs to form network structures in vitro was demonstrated using the tube formation assay. The chick embryo chorioallantoic membrane assay was performed to detect the in vivo anti-angiogenic effect. The expression of VEGF was measured by the enzyme-linked immunosorbent. RESULTS: Results showed that TF-SB inhibited the proliferation and migration of HUVECs in a dose- dependent manner. Simultaneously, TF-SB significantly suppressed HUVEC angiogenesis in vitro and in vivo. Furthermore, VEGF was downregulated in both HUVECs and MHCC97-H cells after TF-SB treatment. CONCLUSION: TF-SB could suppress the process of angiogenesis in vitro and in vivo. TF-SB potentially suppresses angiogenesis in HUVECs by regulating VEGF. These findings suggested that TF-SB may serve as a potent anti-angiogenic agent.

Targeted inhibition of mammalian target of rapamycin (mTOR) enhances radiosensitivity in pancreatic carcinoma cells.

The mammalian target of rapamycin (mTOR) is a protein kinase that regulates protein translation, cell growth, and apoptosis. Rapamycin (RPM), a specific inhibitor of mTOR, exhibits potent and broad in vitro and in vivo antitumor activity against leukemia, breast cancer, and melanoma. Recent studies showing that RPM sensitizes cancers to chemotherapy and radiation therapy have attracted considerable attention. This study aimed to examine the radiosensitizing effect of RPM in vitro, as well as its mechanism of action. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and colony formation assay showed that 10 nmol/L to 15 nmol/L of RPM had a radiosensitizing effects on pancreatic carcinoma cells in vitro. Furthermore, a low dose of RPM induced autophagy and reduced the number of S-phase cells. When radiation treatment was combined with RPM, the PC-2 cell cycle arrested in the G2/M phase of the cell cycle. Complementary DNA (cDNA) microarray and reverse transcription polymerase chain reaction (RT-PCR) revealed that the expression of DDB1, RAD51, and XRCC5 were downregulated, whereas the expression of PCNA and ABCC4 were upregulated in PC-2 cells. The results demonstrated that RPM effectively enhanced the radiosensitivity of pancreatic carcinoma cells.

Antiproliferative and apoptotic effects of ß-elemene on human hepatoma HepG2 cells.

BACKGROUND: ß-elemene, a natural sesquiterpene extracted from the essential oils of Curcuma aromatica Salisb, has been shown to be effective against a wide range of tumors. In this study, the antitumor effect of ß-elemene on a human hepatoma cell line, HepG2, and the mechanism involved have been investigated. METHODS: MTT assay was used to determine the growth inhibition of hepatoma HepG2 cells in vitro. Apoptosis of HepG2 cells were demonstrated by fluorescence microscope with Hoechst 33258 staining and flow cytometry with Annexin V-FITC/PI double staining. Flow cytometry was performed to analyze the cell cycle distribution of HepG2 cells. The mRNA and protein expression of Fas and FasL were measured by RT-PCR and Western blot analysis. RESULTS: MTT results showed that ß-elemene could inhibit the proliferation of HepG2 cells in a time- and dose- dependent manner. Our results showed ß-elemene had positive effect on apoptosis through fluorescence microscope and flow cytometry assay. Furthermore, ß-elemene could induce the cell cycle arrest of the HepG2 cells in the G2/M phase. Fas and FasL expression were obviously increased after ß-elemene treatment in both mRNA and protein level. CONCLUSION: The present study indicates that ß-elemene can effectively inhibit proliferation and induce apoptosis in hepatoma HepG2 cells, and the apoptosis induction is related with up-regulating of Fas/FasL expression.

Protective effects of Scutellaria barbata against rat liver tumorigenesis.

Scutellaria barbata D. Don (S. barbata), a traditional Chinese medicine, is used to treat cancers, inflammation, and urinary diseases. This study aimed to determine any protective effects of S. barbata crude extract (CE-SB) against rat liver tumorigenesis induced by diethylnitrosamine (DENA). Liver malfunction indices in serum were measured by biochemical examination. Hematoxylin and eosin staining was performed to examine liver pathology. Contents of malondialdehyde (MDA) and superoxide dismutase (SOD) were measured in liver homogenates to evaluate oxidative stress. The levels of liver malfunction indices in the CE-SB groups, especially in the CE-SB high dose group, were lower than that of the model group (P<0.05). The results from histological examination indicated that the number of liver nodules in the CE-SB groups decreased compared with the model group (P<0.05). Content of MDA determined in liver was significantly decreased, and level of SOD elevated by CE-SB. CE-SB can inhibit experimental liver tumorigenesis and relieve hepatic injury in rats.

Total flavonoids of Scutellaria barbata inhibit invasion of hepatocarcinoma via MMP/TIMP in vitro.

Metastasis is the major cause of cancer-related deaths. Targeting the process of metastasis has been proposed as a strategy to fight cancer. Scutellaria barbata D. Don (S. barbata), a traditional Chinese medicine, is used for treatment of many diseases, including cancer. This study aimed to determine the anti-metastatic effect of total flavonoids of S. barbata (TF-SB) using the human hepatocarcinoma MHCC97H cell line with high metastatic potential. Our results show that TF-SB could significantly inhibit the proliferation and invasion of MHCC97H cells in a dose-dependent manner. MMP-2 and MMP-9 expression were obviously decreased after TF-SB treatment at both the mRNA and protein level. TIMP-1 and TIMP-2 expression were simultaneously increased. The present study indicates that TF-SB could reduce the metastatic capability of MHCC97H cell, probably through decrease of the MMP expression, and simultaneous increase of the TIMP expression.

Antitumor effects of rapamycin in pancreatic cancer cells by inducing apoptosis and autophagy.

Rapamycin (Rapa), an inhibitor of mammalian target of Rapamycin (mTOR), is an immunosuppressive agent that has anti-proliferative effects on some tumors. This study aims to investigate the effects of Rapa suppressing proliferation of pancreatic carcinoma PC-2 cells in vitro and its molecular mechanism involved in antitumor activities. MTT assays showed that the inhibition of proliferation of PC-2 cells in vitro was in a time- and dose-dependent manner. By using transmission electron microscopy, apoptosis bodies and formation of abundant autophagic vacuoles were observed in PC-2 cells after Rapa treatment. Flow cytometry assays also showed Rapa had a positive effect on apoptosis. MDC staining showed that the fluorescent density was higher and the number of MDC-labeled particles in PC-2 cells was greater in the Rapa treatment group than in the control group. RT-PCR revealed that the expression levels of p53, Bax and Beclin 1 were up-regulated in a dose-dependent manner, indicating that Beclin 1 was involved in Rapa induced autophagy and Rapa induced apoptosis as well as p53 up-regulation in PC-2 cells. The results demonstrated that Rapa could effectively inhibit proliferation and induce apoptosis and autophagy in PC-2 cells.

Determination of ethambutol by a sensitive fluorescent probe.

The competitive reaction between ethambutol and two fluorescent probes (i.e., berberine and palmatine) for occupancy of the cucurbit[7]uril (CB[7]) cavity was studied by spectrofluorometry. The CB[7] reacts with these probes to form stable complexes, and the fluorescence intensity of the complexes is greatly enhanced. In addition, the excitation and emission wavelengths of their complexes moved to wavelengths of 343 nm and 495 nm, respectively. However, the addition of ethambutol dramatically quenches the fluorescence intensity of the two complexes. Accordingly, a couple of new fluorescence quenching methods for the determination of ethambutol were established. The methods can be applied for quantifying ethambutol. A linear relationship between the fluorescence quenching values (ΔF) and ethambutol concentration exists in the range of 5.0-1000.0 ng mL(-1), with a correlation coefficient (r) of 0.9997. The detection limit is 1.7 ng mL(-1). The fluorescent probe of berberine has higher sensitivity than palmatine. This paper also discusses the mechanism of fluorescence indicator probes.

Supramolecular interaction of cucurbit[n]urils and coptisine by spectrofluorimetry and its analytical application.

The supramolecular interaction of a homologous series of cucurbit[n]uril (CB[n], n=5, 6, 7, 8) hosts and coptisine (COP) was studied by spectrofluorimetry. All of the CB[n]s were found to react with COP to form 1:1 host-guest stable complexes and the fluorescence intensity of the complexes was greatly enhanced. The apparent association constants of the complexes were 1.44 x 10(4), 1.28 x 10(4), 1.86 x 10(4) and 1.26 x 10(4)L mol(-1) for CB[5], CB[6], CB[7] and CB[8], respectively. In addition, CB[5] and CB[7] exhibited a higher fluorescence signal than CB[6] and CB[8]. The fluorescence intensity of the complex with CB[7] was enhanced 70-fold compared to that of the studied drug itself. Based on the significant enhancement of fluorescence intensity of supramolecular complex, a simple, rapid, highly sensitive, and selective spectrofluorimetric method was developed for the determination of COP in aqueous solution in the presence of CB[7]. At the optimum reaction conditions, a linear relationship was obtained in the range from 0.05 to 1700 ng mL(-1) with a detection limit of 0.012 ng mL(-1). The proposed method was successfully applied for the determination of the drug in urine and serum samples.

Matrine induces apoptosis in gastric carcinoma cells via alteration of Fas/FasL and activation of caspase-3.

AIM OF THE STUDY: Matrine, an alkaloid purified from the chinese herb Sophora flavescens Ait, is well known to possess activities including anti-inflammation, anti-fibrotic and anticancer. In this study, the mechanism of matrine inducing the apoptosis of gastric carcinoma cells was investigated. MATERIALS AND METHODS: Proliferation of SGC-7901 cells was examined by MTT assay. Cellular morphology was observed under transmission electron microscope. Flow cytometry (FCM) was used to observe the apoptosis of SGC-7901 cells by staining with annexinV-FITC/PI. The expression levels of Fas/FasL in SGC-7901 cells were monitored by FCM analysis using an indirect immunofluorescence method. Activity of caspase-3 enzyme was measured by spectrofluorometry. RESULTS: MTT assay showed that matrine inhibited SGC-7901 cells proliferation in a dose-dependent and time-dependent manner. Apoptosis induction was demonstrated by morphological changes under electron microscope and FCM analysis. Fluorescence intensity levels of Fas and FasL were found to be equally up-regulated after matrine treatment, which were both correlated with apoptosis rate. The activity of caspase-3 enzyme increased in matrine groups, positively correlated with apoptosis rate. CONCLUSIONS: Matrine could inhibit cell proliferation and induce apoptosis of SGC-7901 cells in vitro. The apoptosis induction appears to proceed by up-regulating Fas/FasL expression and activating caspase-3 enzyme.

[Apoptotic mechanism of gastric carcinoma cells induced by matrine injection].

OBJECTIVE: To investigate the mechanism of gastric carcinoma cells apoptosis induced by matrine injection in vitro. METHODS: Effects of 24, 48, 72, 96 h incubation with different concentrations (0.25-1.5 g/L) of matrine injection on proliferation of SGC-7901 cells were evaluated using 3-4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide (MTT) assay. The cellular morphology of SGC-7901 cells was observed by transmission electron microscope (EM). Flow cytometry was used to analyze the apoptosis of SGC-7901 cells by staining with annexin V-FITC/PI. The expression of Fas/FasL was examined by flow cytometry using specific antibody. The activity of caspase-3 was measured by spectrofluorometry. RESULTS: Matrine injection could inhibit the proliferation of SGC-7901 cells in a dose- and time-dependent manner. The typical morphological changes of apoptosis were observed after incubation with 1.0 g/L matrine injections for 48 h. The apoptosis rates of 0.5 g/L, 1.0 g/L and 1.5 g/L groups were 39.80%, 58.11% and 79.00% respectively. The apoptotic cells in matrine injection group were mainly early apoptotic cells, and those in 5-FU group were mainly late apoptotic cells and necrotic cells. Spectrofluorometry revealed FI levels of Fas and FasL were equal, which were both correlated with apoptosis rate. The activity of caspase-3 increased with the elevation of matrine concentration, and was correlated with the apoptosis rate. CONCLUSION: Matrine injection can induce apoptosis of SGC-7901 cells through the up-regulation of Fas/FasL expression and activation of caspase-3.

[Effect of matrine injections on invasion and metastasis of gastric carcinoma SGC-7901 cells in vitro].

OBJECTIVE: To investigate the effect of matrine injections on invasion and metastasis of gastric carcinoma SGC-7901 cells in vitro. METHODS: MTT assay was used to examine the effect of matrine injections on proliferation of SGC-7901 cells after 24, 48, 72, 96 hours treatment; Transwell chamber assay was performed to determine the effect of matrine injection on invasion and migratory capacity of the cells; Effect on adhesion potential of SGC-7901 cells was tested by cell matrigel adhesion assay. RESULTS: Matrine injec-tions could inhibit the proliferation of SGC-7901 cells, with obvious dose-dependent and time-dependent effects. Matrine injections sig-nificantly inhibited adhesion, invasion and migration capacity of SGC-7901 cells in vitro. The inhibitory rate of them after treatment with 1.5 mg/ml matrine injections for 24 h were (45.32 +/- 3.10)%, (32.66 +/- 2.82)%, (38.35 +/- 3.41)% respectively. After treat-ment of matrine injections (1.5 mg/ml)for 24 h, the expression level of CD44(V6) in SGC-7901 cells was decreased compared with the untreated group. CONCLUSION: Matrine injections can inhibit the migration, invasion and adhesion capacity of SGC-7901 cells in vitro. The inhibition effect may be related to down-regulating the expression of CD44(V6) protein.

Cloning and GST-fused expression in E. coli of mouse beta-1,4-galactosyltransferase.

Beta-1,4-galactosyltransferase (beta4Gal-T) (EC 2.4.1.38) plays a multifunctional role in many aspects of normal cell physiology. By now, several dozens of beta4Gal-T genes have been cloned, separated from mouse, chick, bovine, human, etc. This paper presents the cloning and GST-fused expression of mouse beta4Gal-T gene in Escherichia coli (E. coli). The target gene was cloned by PCR, followed by identification by DNA sequencing and expression in E.coli with isopropyl-beta-D-thiogalactoside (IPTG) gradient concentrations, products of which were separated on SDS-PAGE showing that the target protein had the same molecular weight as that of mouse beta4Gal-T. The transcriptional product of beta4Gal-T gene was proved by Western hybridization analysis to be due to GST-fusion.