Extraction, purification, structural characterization, and bioactivities of the genus Rhodiola L. polysaccharides: A review.

The genus Rhodiola L., an integral part of traditional Chinese medicine and Tibetan medicine in China, exhibits a broad spectrum of applications. This genus contains key compounds such as ginsenosides, polysaccharides, and flavonoids, which possess anti-inflammatory, antioxidant, hypoglycaemic, immune-enhancing, and anti-hypoxic properties. As a vital raw material, Rhodiola L. contributes to twenty-four kinds of Chinese patent medicines and 481 health food products in China, finding extensive application in the health food sector. Recently, polysaccharides have emerged as a focal point in natural product research, with applications spanning the medicine, food, and materials sectors. Despite this, a comprehensive and systematic review of polysaccharides from the genus Rhodiola L. polysaccharides (TGRPs) is warranted. This study undertakes a systematic review of both domestic and international literature, assessing the research advancements and chemical functional values of polysaccharides derived from Rhodiola rosea. It involves the isolation, purification, and identification of a variety of homogeneous polysaccharides, followed by a detailed analysis of their chemical structures, pharmacological activities, and molecular mechanisms, structure-activity relationship (SAR) of TGRPs. The discussion includes the influence of molecular weight, monosaccharide composition, and glycosidic bonds on their biological activities, such as sulfation and carboxymethylation et al. Such analyses are crucial for deepening the understanding of Rhodiola rosea and for fostering the development and exploitation of TGRPs, offering a reference point for further investigations into TGRPs and their resource utilization.

miRNA-223 expression in patient-derived eutopic and ectopic endometrial stromal cells and its effect on epithelial-to-mesenchymal transition in endometriosis.

OBJECTIVE: This study was designed to evaluate the expression of microRNA-223 (miRNA-223) in patient-derived eutopic and ectopic endometrial stromal cells (SCs). Given the fact that miRNA-223 was previously shown to be upregulated in these cells and that this upregulation has been linked to epithelial-to-mesenchymal transition (EMT) during endometriosis, this study aimed to further explore the expression of miRNA-223, its effect in endometriosis, and the mechanisms underlying its effects. METHODS: Endometrial tissue was collected from 26 patients with endometriosis and 14 patients with hysteromyoma (control group). Primary endometrial SCs were isolated and cultured from several endometrial samples and miRNA-223 expression was evaluated using qRT-PCR. Cells were then transfected with a miRNA-223 overexpression lentiviral vector (sh-miR-223 cells) or an empty control (sh-NC cells) and then used to monitor the effects of miRNA-223 on the expression of several EMT-associated proteins, including N-cadherin, vimentin, and Slug, using western blot. Cellular migration, invasion, and proliferation were then evaluated using a wound healing, Transwell, and CCK-8 assay, respectively. Flow cytometry was used to detect apoptosis. RESULTS: There was a significant decrease in the expression of miRNA-223 in both eutopic and ectopic endometrial SCs (p < 0.05) whereas upregulation of miRNA-223 inhibited the expression of EMT-related molecules and reduced cell migration, invasion, and proliferation. High levels of miRNA-223 also promoted apoptosis. CONCLUSION: miRNA-223 expression decreased in endometrial SCs from endometriosis patients, which may facilitate the differential regulation of EMT during endometriosis. CLINICAL TRIAL REGISTRATION NUMBER: SWYX2020-211.

Pancancer Analysis of Revealed TDO2 as a Biomarker of Prognosis and Immunotherapy.

Background: Tryptophan 2,3-dioxygenase (TDO) encoded by TDO2, a rate-limiting enzyme in the kynurenine pathway, catabolizes tryptophan to kynurenine, evades immune surveillance, and promotes tumor growth. Although accumulating evidence suggests a crucial role of TDO2 during tumor formation and development, systematic evaluation of TDO2 across human cancers has rarely been reported. Methods: To shed more light on the role of TDO2 in human cancer, we explored the expression profiles of TDO2 and identified its prognostic value in pancancer analysis through TCGA, CCLE, and GTEx databases. We further utilized TCGA data to evaluate the association between TDO2 and tumor immunological features, such as mismatch repair (MMR), tumor immune infiltration, immune checkpoint-related genes, tumor mutational burden (TMB), microsatellite instability (MSI), and DNA methyltransferase (DNMT). Results: TDO2 exhibited different expression levels in various cancer cell lines. Frequently, TDO2 was detected to be highly expressed in the majority of cancers. In addition, high TDO2 expression was correlated with an unfavorable prognosis for patients in KIRP, LGG, TGCT, and UVM. Moreover, high TDO2 expression level positively correlated with higher immune infiltration, especially dendritic cells. Additionally, there is a close relationship between TDO2 and immune checkpoint-related gene markers, such as LAIR1, CD276, NRP1, CD80, and CD86. Finally, correlation analysis has demonstrated a high-correlation between TDO2 and TMB, MSI, MMR, and DNMT of multiple cancer types. Conclusion: Therefore, our results suggest that TDO2 can function as a potential prognostic biomarker due to its role in tumor immunity regulation.

Design of Transverse Brachiation Robot and Motion Control System for Locomotion between Ledges at Different Elevations.

Bio-inspired transverse brachiation robots mimic the movement of human climbers as they traverse along ledges on a vertical wall. The constraints on the locomotion of these robots differ considerably from those of conventional brachiation robots due primarily to the need for robust hand-eye coordination. This paper describes the development of a motion control strategy for a brachiation robot navigating between wall ledges positioned on a level plane or at different elevations. We based our robot on a four-link arm-body-tail system performing a four-phase movement, including a release phase, body reversal phase, swing-up phase, and grasping phase. We designed a gripper that uses passive wrist joint motion to grasp the ledge during the tail swing. We also developed a dynamic model by which to coordinate the swing-up movement, define the phase switching conditions, and time the grasping action of the grippers. In experiments, the robot proved highly effective in traversing between wall ledges of the same or different elevations.

Differentially expressed EREG and SPP1 are independent prognostic markers in cervical squamous cell carcinoma.

AIMS: Cervical squamous cell carcinoma (SCC) is one of the most frequent malignancies of the female reproductive system. The malignant mechanism of SCC has not been totally clarified. We aimed to discover a list of differentially expressed genes (DEGs) to identify the malignant mechanism of cervical SCC. METHOD: Three expression chips (GSE7803, GSE9750, and GSE64217) were downloaded from gene expression omnibus (GEO) datasets. After standardization, 50 cervical SCC tumor tissues and 33 normal cervical tissues (NCTs) were included for DEGs and clustering analysis. RobustRankAggreg (RRA) algorithm was used to extract the overlapping DEGs. Gene function and signaling pathway analysis was implemented based on Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway databases. Protein-protein interaction (PPI) analysis and prognostic analysis were also carried out to identify the DEGs as prognostic markers for cervical SCC. RESULTS: Totally 100 DEGs were obtained from GSE7803, 319 DEGs from GSE9750, and 1639 DEGs from GSE64217. RRA analysis uncovered 17 upregulated DEGs and 25 downregulated DEGs. GO and KEGG analysis showed DEGs were involved in the mediation of extracellular functions, cell-cell interactions, and cell metabolism. PPI network showed a close interaction among the integrated DEGs. Prognostic analysis showed gene secreted phosphoprotein 1 (SPP1) and epiregulin (EREG) genes were independent prognostic predictors of cervical SCC. CONCLUSION: The gene expression profile was changed in cervical SCC tumor tissues compared to NCTs. SPP1 and EREG were postulated as prognostic markers for cervical SCC, which might be potential targets for clinical therapy of cervical SCC.

miRNA-223 expression in patient-derived eutopic and ectopic endometrial stromal cells and its effect on epithelial-to-mesenchymal transition in endometriosis

Abstract Objective: This study was designed to evaluate the expression of microRNA-223 (miRNA-223) in patient-derived eutopic and ectopic endometrial stromal cells (SCs). Given the fact that miRNA-223 was previously shown to be upregulated in these cells and that this upregulation has been linked to epithelial-to-mesenchymal transition (EMT) during endometriosis, this study aimed to further explore the expression of miRNA-223, its effect in endometriosis, and the mechanisms underlying its effects. Methods: Endometrial tissue was collected from 26 patients with endometriosis and 14 patients with hysteromyoma (control group). Primary endometrial SCs were isolated and cultured from several endometrial samples and miRNA-223 expression was evaluated using qRT-PCR. Cells were then transfected with a miRNA-223 overexpression lentiviral vector (sh-miR-223 cells) or an empty control (sh-NC cells) and then used to monitor the effects of miRNA-223 on the expression of several EMT-associated proteins, including N-cadherin, vimentin, and Slug, using western blot. Cellular migration, invasion, and proliferation were then evaluated using a wound healing, Transwell, and CCK-8 assay, respectively. Flow cytometry was used to detect apoptosis. Results: There was a significant decrease in the expression of miRNA-223 in both eutopic and ectopic endometrial SCs (p < 0.05) whereas upregulation of miRNA-223 inhibited the expression of EMT-related molecules and reduced cell migration, invasion, and proliferation. High levels of miRNA-223 also promoted apoptosis. Conclusion: miRNA-223 expression decreased in endometrial SCs from endometriosis patients, which may facilitate the differential regulation of EMT during endometriosis. Clinical Trial registration number: SWYX2020-211.

Chemokine CCL20 promotes the paclitaxel resistance of CD44+CD117+ cells via the Notch1 signaling pathway in ovarian cancer.

Studies have found that C­C motif chemokine ligand 20 (CCL20)/C­C motif chemokine receptor 6 (CCR6)/notch receptor 1 (Notch1) signaling serves an important role in various diseases, but its role and mechanism in ovarian cancer remains to be elucidated. The aim of the present study was to investigate the underlying mechanism of CCL20/CCR6/Notch1 signaling in paclitaxel (PTX) resistance of a CD44+CD117+ subgroup of cells in ovarian cancer. The CD44+CD117+ cells were isolated from SKOV3 cells, followed by determination of the PTX resistance and the CCR6/Notch1 axis. Notch1 was silenced in the CD44+CD117+ subgroup and these cells were treated with CCL20, followed by examination of PTX resistance and the CCR6/Notch1 axis. Furthermore, in nude mice, CD44+CD117+ and CD44­CD117­ cells were used to establish the xenograft model and cells were treated with PTX and/or CCL20, followed by proliferation, apoptosis, reactive oxygen species (ROS) and mechanism analyses. Higher expression levels of Oct4, CCR6, Notch1 and ATP binding cassette subfamily G member 1 (ABCG1), increased sphere formation ability, IC50 and proliferative ability, as well as lower ROS levels and apoptosis were observed in CD44+CD117+ cells compared with the CD44­CD117­ cells. It was found that CCL20 could significantly increase the expression levels of Oct4, CCR6, Notch1 and ABCG1, enhance the IC50, sphere formation ability and proliferation, as well as decrease the ROS and apoptosis levels in the CD44+CD117+ cells. However, Notch1 knockdown could markedly reverse these changes. Moreover, CCL20 could significantly increase the proliferation and expression levels of Oct4, CCR6, Notch1 and ABCG1 in the CD44+CD117+ groups compared with the CD44­CD117­ groups. After treatment with PTX, apoptosis and ROS levels were decreased in the CD44+CD117+ groups compared with the CD44­CD117­ groups. Collectively, the present results demonstrated that, via the Notch1 pathway, CCL20/CCR6 may promote the stemness and PTX resistance of CD44+CD117+ cells in ovarian cancer.

The Drug Combination of SB202190 and SP600125 Significantly Inhibit the Growth and Metastasis of Olaparib-resistant Ovarian Cancer Cell.

BACKGROUND & OBJECTIVE: Many targeted ovarian cancer patients are resistant to olaparib treatment. Here we seek to understand the underlying molecular events and search for potential combinational therapeutics to surmount the intrinsic olaparib resistance in human ovarian cancer. METHODS: The cytotoxicity was determined by the MTT assay and cell viability was measured using Cell Counting Kit-8 (CCK-8). Protein expressions of ERK, P38, JNK, ERK5, LC3, N-CADHERIN, α-SMA were determined by western blotting. The invasion capacity was evaluated by the transwell chamber. Autophagy flux was monitored by the LC3 puncta formation. The epithelial-mesenchymal transition (EMT) markers were profiled by immunoblotting detection. The in vivo tumor progression was determined by xenograft mice model. RESULTS: The olaparib-resistant cell lines were successfully generated in both SKOV3 and A2780 cells. The proliferative index was significantly higher in resistant cells in comparison with sensitive counterparts in the presence of olaparib. Both P38 and JNK were up-regulated in olaparib-resistant cells. The combinational treatment with P38-specific inhibitor SB202190 and JUN-specific inhibitor SP600125 significantly suppressed cell growth and migration, which was further attributed to the induction of autophagy flux and inhibition of EMT processing. We further consolidated the anti-tumor activities of SB202190 and SP600125 in xenograft mice. CONCLUSION: Our data suggested that aberrant over-expression of P38 and JNK is causally linked to the olaparib resistance in ovarian cancer. Combination of P38 and JUN inhibitors demonstrated significant anti-tumor activity both in vitro and in vivo. Our study highlighted the potential therapeutic value of Mitogen-Activated Protein Kinase (MAPK) inhibitors in olaparib-resistant human ovarian cancer.

Luteolin promotes the sensitivity of cisplatin in ovarian cancer by decreasing PRPA1-medicated autophagy.

Luteolin (LUT) is a flavone universally presented in plants. It shows an anti-carcinogenic effect in different cancers and could increase the sensitivity of cisplatin in colorectal cancer cell lines through Nrf2 pathway. However, the effect of luteolin on the sensitivity to ovarian cancer cells has not been studied. In this study, luteolin was found to suppress autophagy with reduced expression of LC3-II, but enhanced the inhibition of cell vitality and promoted apoptosis induced by cisplatin, leading to restoration of the sensitivity to cisplatin in ovarian cancer cells through CCK-8, flow cytometry and immunofluorescent assays. Although cisplatin elevated the PARP1 for cell survival, the cisplatin-induced expression of PARP1 was inhibited by luteolin a dose- and time- dependent manner through Q-PCR and WB assays. Further, PARP1 siRNA could further improve the LUT-induced inhibition of cell vitality and restore the sensitivity to cisplatin with reduced LC3-II levels. Our present work demonstrate that LUT can suppresses autophagy but enhance apoptosis induced by cisplatin and promote the sensitivity to cisplatin through suppressing the expression of RARP1 in ovarian cancer.

miR-206 Inhibits Cell Proliferation, Migration, and Invasion by Targeting BAG3 in Human Cervical Cancer.

miR-206 and Bcl-2-associated athanogene 3 (BAG3) have been suggested as important regulators in various cancer types. However, the biological role of miR-206 and BAG3 in cervical cancer (CC) remains unclear. We investigated the expressions and mechanisms of miR-206 and BAG3 in CC using in vitro and in vivo assays. In the present study, miR-206 expression was expressed at a lower level in CC tissues and cells than adjacent normal tissues and NEECs. By contrast, BAG3 mRNA and protein were expressed at higher levels in CC tissues and cells. Furthermore, miR-206 overexpression repressed cell proliferation, migration, and invasion in vitro, and the 3'-untranslated region (3'-UTR) of BAG3 was a direct target of miR-206. miR-206 overexpression also inhibited EGFR, Bcl-2, and MMP2/9 protein expression, but promoted Bax protein expression. Besides, BAG3 overexpression partially abrogated miR-206-inhibited cell proliferation and invasion, while BAG3 silencing enhanced miR-206-mediated inhibition. In vivo assay revealed that miR-206 repressed tumor growth in nude mice xenograft model. In conclusion, miR-206 inhibits cell proliferation, migration, and invasion by targeting BAG3 in human CC. Thus, miR-206-BAG3 can be used as a useful target for CC.

Potential role of HGF-PARP-1 signaling in invasion of ovarian cancer cells.

We investigated the effects and signaling pathways involved in both HGF-mediated regulation of PARP-1 expression and the invasion ability of ovarian cancer cells. Using a transwell assay, the invasiveness of SKOV-3 cells was tested by incubating them with increasing concentrations of HGF. The relative expression levels of PARP-1 after HGF treatment were analyzed by Real-Time PCR and western blotting. SKOV3 cells were transfected with either negative control siRNA or PARP-1 siRNA, and were divided into different groups as follows: control group; HGF group; PARP-siRNA group; HGF+PARP-siRNA group; NC-siRNA group; and HGF+NC-siRNA group. Western blotting was employed to measure the expression of PARP-1 in the different groups. Transwell tests were used to examine invasiveness. ELISA was applied to measure MMP-2 expression. HGF promotes cell invasion in a concentration- and time-dependent manner in SKOV-3 cells. The expression levels of PARP-1 increased after administration of 40 ng/ml HGF for 24 h. The expression of PARP-1 in the PARP1-siRNA group was lower compared with that in the NC-siRNA group (P < 0.05); PARP1-siRNA transfection significantly reduced the impact of HGF on invasiveness and MMP-2 expression in SKOV-3 cells. HGF promotes the invasiveness and metastasis of ovarian cancer cells. This effect could be related to the induction of increased expression levels of MMP-2 mediated by PARP-1.

Construction and comparison of yeast whole-cell biosensors regulated by two RAD54 promoters capable of detecting genotoxic compounds.

Two yeast enhanced green fluorescence protein (yEGFP) yeast reporter vectors, pR1558-yEGFP and pR406-yEGFP, which are regulated by two RAD54 promoters containing 406-bp and 1558-bp DNA sequences, respectively, were constructed using molecular biological techniques and transformed into yeast for the screening of genotoxins. The constructed biosensors were named W303-1A/R1558-yEGFP and W303-1A/R406-yEGFP. To quantify biosensor performance, both transformed yeast cells were exposed to multiple doses of genotoxins including methylmethane sulfonate (MMS; a DNA alkylating agent), 4-nitroquinoline-N-oxide (4-NQO; a DNA cleavage agent), 5-fluorouracil (5-Fu; an inhibitor of polymerases and topoisomerases) and colchicine and canavanine (affecting other biochemical activities). The yeast bioassay performance was analyzed using fluorescence-activated cell sorting (FACS) and Multi-Mode Reader in a 96-well black microplate. The observed W303-1A/R1558-yEGFP dose-effect relationship was more obvious and the maximum inductions were 5.96-fold (MMS), 2.19-fold (4-NQO) and 2.71-fold (5-Fu); the corresponding values for W303-1A/R406-yEGFP were 2.53-, 1.50- and 1.91-fold, respectively. It is suggested that it is best to select the entire RAD54 promoter when constructing recombinant yeast cells for screening mutagens.

Tunable mode rotator for space-division multiplexing based on a few mode-polarization maintaining fiber.

In this paper, a fiber-based tunable mode rotator is proposed and demonstrated by using the few mode-polarization maintaining fiber (FM-PMF). The mode birefringence in the FM-PMF causes phase difference between two orthogonal degenerate modes. With rotating the FM-PMF segment and getting a variation of aligning angle between the injected LP11 (LP21) mode axis and FM-PMF axis, another intended LP11 (LP21) mode with a certain orientation can be controllably generated at the FM-PMF output.

Effects of PARP-1 inhibitor and ERK inhibitor on epithelial mesenchymal transitions of the ovarian cancer SKOV3 cells.

BACKGROUND: To assess the effects of the poly (ADP-ribose) polymerase-1 (PARP-1) inhibitor PJ34 and ERK1/2 inhibitor U0126 on the proliferation and epithelial mesenchymal transitions (EMT) of cisplatin resistant ovarian cancer SKOV-3 cells. METHODS: Proliferation of SKOV-3 cells was evaluated using a 3-(4,5-dimethylthazol-2-yl)-2,5-diphenyl tetrazolium bromide assay with PJ34 and U0126 treatment. Expression changes of E-cadherin and vimentin with PJ34 and U0126 treatment was examined using Western blot and quantitative PCR. In addition, invasion assay was performed in cells treated with PJ34 and U0126. RESULTS: PJ34 and U0126 inhibited proliferation of SKOV-3 cells in a time dependent manner. PJ34 and U0126 suppressed the expression of vimentin and enhanced the expression of E-cadherin. PJ34 and U0126 reduced cell invasion. The inhibitory effects of PJ34 and U0126 were stronger than PJ34 alone. PJ34 inhibited the proliferation and invasion of SKOV-3 cells which can be enhanced by ERK1/2 inhibitor U0126. CONCLUSIONS: These inhibitory effects are partially due to PARP-1 and ERK1/2 mediated attenuation of EMT activity.

shRNA-mediated AMBRA1 knockdown reduces the cisplatin-induced autophagy and sensitizes ovarian cancer cells to cisplatin.

Recent research has revealed a role for Ambra1, an autophagy-related gene-related (ATG) protein, in the autophagic pro-survival response, and Ambra1 has been shown to regulate Beclin1 and Beclin1-dependent autophagy in embryonic stem cells and cancer cells. However, whether Ambra1 plays an important role in the autophagy pathway in ovarian cancer cells is unknown. In this study, we hypothesized that Ambra1 is an important regulator of autophagy and apoptosis in ovarian cancer cells. We firstly confirmed autophagic activity in ovarian cancer OVCAR-3 cells which were treated with cisplatin by assessing endogenous microtubule-associated protein 1 light chain 3 (LC3) localization and the presence of autophagosomes and LC3 protein levels in OVCAR-3 cells. Cell apoptosis and viability were measured by annexin-V and PI staining and MTT assays. We then knocked down Ambra1 expression with transfection with the plasmid expressing the small hairpin RNA (shRNA) targeting AMBRA1, then re-evaluated autophagy in the OVCAR-3 cells subject to cisplatin treatment, and re-determined the sensitivity of OVCAR-3 cells to cisplatin. Results demonstrated that cisplatin treatment induced autophagy in OVCAR-3 cells in association with Ambra1 upregulation in the ovarian cancer cells. When Ambra1 expression was reduced by shRNA, the ovarian cancer cells were more sensitive to cisplatin. In conclusion, Ambra1 is a crucial regulator of autophagy and apoptosis in ovarian cancer cells subject to cisplatin to maintain the balance between autophagy and apoptosis. And the Ambra1-targeting inhibition might be an effective method to sensitize ovarian cancer cells to chemotherapy.

PARP-1 may be involved in angiogenesis in epithelial ovarian cancer.

Poly (ADP-ribose) polymerase 1 (PARP-1) is involved in DNA repair and has been implicated in chemoresistance. The present study investigated whether PARP-1 promotes angiogenesis in ovarian cancer. PARP-1 and vascular endothelial growth factor A (VEGF-A) expression and CD34+ microvascular density (MVD) were assessed using immunohistochemistry in 60 human epithelial ovarian cancer specimens. PARP-1 was stably knocked-down in SKOV3 cells using a specific small interfering RNA (siRNA); angiogenic capacity was assessed using the human umbilical vein endothelial cell (HUVEC) tubule formation assay; and PARP-1 and VEGF-A expression were examined by reverse transcription-quantitative polymerase chain reaction, western blotting and ELISA. PARP-1 was found to be expressed in 73.3% (44/60) of the human epithelial ovarian cancer specimens and was significantly associated with VEGF-A, MVD, tumor size, histological grade and lymphatic metastasis (P<0.05). Compared with cells transfected with a negative control siRNA, knockdown of PARP-1 significantly suppressed the ability of SKOV3 cell-conditioned media to promote HUVEC tubule formation on Matrigel in vitro. Knockdown of PARP-1 in SKOV3 cells also significantly reduced VEGF-A mRNA and protein expression and secretion. In summary, PARP-1 is overexpressed and may enhance angiogenesis in epithelial ovarian cancer by upregulating VEGF-A.

[Construction of a Recombinant Lac Z Gene in Yeast Cell for Rapid Detection of Tetracycline Antibiotics].

Two vectors were used to construct the recombinant gene yeast cell that can be used to bioassay of the pollution of tetracycline antibiotics in the environment.In the expression vector,the GPD(glyceraldehyde-3-phosphate dehydrogenase)promoter was used to drive the gene expression of tetracycline repressor protein(TR)fused with V5 antigen epitope gene,while in the reporter vector,the tetracycline response element(TRE)was used to regulate Lac Z report gene expression.The specificity and the sensitivity of the recombinant gene yeast cell were evaluated respectively by different concentrations of tetracycline antibiotics and non-tetracycline antibiotics.The results showed that there were significant dose effect relationships between the tetracycline antibiotics and the yeast cells,while non-tetracycline antibiotics showed no dose effect relationships with this biosensor.It is illustrated that the recombinant yeast cells can be used to monitor the tetracycline antibiotic pollution on the environment.

Dual fluorescent protein-based bioassay system for the detection of genotoxic chemical substances in Saccharomyces cerevisiae.

A new reporter system has been developed for quantifying the activity of potentially DNA-damaging substances in the yeast Saccharomyces cerevisiae. The system relies on two different reporter genes, yEGFP and DsRed-Express2, to screen for DNA-damaging chemicals. The yEGFP gene is fused to the test promoter of RNR2, whose measurable signal has a dose-dependent relationship with DNA damage. The gene encoding DsRed-Express2 is fused to a constitutive promoter of GPD, providing an internal control for normalizing cell numbers in the assay. The dual fluorescent protein assay system is performed by sequentially measuring the yEGFP and DsRed-Express2 fluorescent intensity of the same sample, with the results expressed as the ratio of yEGFP to DsRed-Express2 intensity (yEGFP/DsRed-Express2). The yeast fluorescent protein reporter assay was performed in 96-well microtiter plates in the presence of different concentrations of test substances, which were then characterized. The assay was very efficient, high-throughput, and amenable to full automation. Here, we demonstrate that this system can be used as a biosensor to assess the genotoxic potential of drugs and other chemical substances.

MiR-302a inhibits the tumorigenicity of ovarian cancer cells by suppression of SDC1.

MicroRNA plays an important role in tumor proliferation and cell cycle. In this study, we suggested the level of miR-302a was increasing in the human ovarian cancer cells compared to the normal cells. We aimed to explore the role of miR-302a downregulation in human ovarian cancer cells. Functional studies demonstrate over expression of miR-302a could significant suppress ovarian cancer cells proliferation and promote the cell cycle progress. In vitro reporter assay suggested SDC1 is a direct target gene of miR-302a. Furthermore, the expressions of miR-302a in ovarian cancer cells were inversely corrected with that of SDC1. Upregulation of SDC1 could rescue the effect of over expressed miR-302a in the ovarian cancer cells. These findings provide evidence that miR-302a plays a key role in inhibition of the ovarian cancer cells proliferation, and enhancing the cells' apoptosis through targeting SDC1, and strongly suggest that exogenous miR-302a may have therapeutic value in treating ovarian cancer.