Circ_LDLR promoted the development of papillary thyroid carcinoma via regulating miR-195-5p/LIPH axis.

BACKGROUND: Emerging studies have demonstrated that circular RNAs (circRNAs) are key regulators for tumorigenesis in cancers, including papillary thyroid carcinoma (PTC). In this study, we aimed to explore the effects of circ_LDLR on PTC. METHODS: Quantitative real-time polymerase chain reaction (qRT-PCR) was performed to determine the levels of circ_LDLR, miR-195-5p and lipase H (LIPH). RNase R digestion assay and Actinomycin D assay were utilized to analyze the characteristics of circ_LDLR. Colony formation assay and 3-(4,5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2-H-tetrazolium bromide (MTT) assay were conducted to evaluate cell proliferation. Western blot assay was used for the determination of protein levels. Flow cytometry analysis was applied to determine cell apoptosis. Transwell assay was performed to determine cell migration and invasion. Dual-luciferase reporter assay was used to verify the associations among circ_LDLR, miR-195-5p and LIPH. The murine xenograft model was constructed to explore the roles of circ_LDLR in vivo. RESULTS: Compared to normal tissues and cells, circ_LDLR was upregulated in PTC tissues and cells. Silencing of circ_LDLR suppressed PTC cell colony formation, proliferation, migration and invasion and promoted apoptosis in vitro and hampered tumor growth in vivo. For mechanism investigation, circ_LDLR could regulate LIPH expression via sponging miR-195-5p. Moreover, miR-195-5p inhibition restored the effects of circ_LDLR knockdown on the malignant behaviors of PTC cells. MiR-195-5p overexpression inhibited PTC cell colony formation, proliferation, migration and invasion and facilitated apoptosis by targeting LIPH. CONCLUSION: Circ_LDLR knockdown decelerated PTC progression by regulating miR-195-5p/LIPH axis, which might provide a novel therapeutic target for PTC.

Subpopulations of cancer stem cells found in papillary thyroid carcinoma.

Papillary thyroid carcinoma (PTC) is the most common form of thyroid cancer and while it has a generally good prognosis, tumor recurrence remains a major clinical challenge. Studying laboratory cell lines as well as clinical specimens indicate that PTC may follow the cancer stem cell (CSC) model. However, CSC characteristics relevant in PTC initiation and progression remain largely unknown. Here we studied a population of sphere-growing tumor cells isolated from primary cultures of clinical PTC. These sphere-growing cells consisted of aldehyde dehydrogenase positive (ALDH+) and ALDH negative (ALDH-) cell subpopulations and demonstrated a hierarchical pattern of cell division. Using combinations of selective depletion, specific inhibition and cell sorting, we found that both subpopulations of the sphere cells were able to self-renew and initiate xenograft tumors independently, and fulfilled the definition of CSC. Importantly, when the subpopulations functioned together, the cancer-initiation efficiency and the xenograft tumor progression were significantly enhanced compared to either subpopulation alone. These data revealed crucial roles of ALDH- CSC in PTC biology and suggested that CSC subpopulations function cooperatively to control PTC initiation and progression. Together, our study indicates that CSC subpopulations isolated from clinical specimens offer unprecedented opportunities for investigating PTC pathogenesis and developing effective therapies.

Distinct Diagnostic and Prognostic Values of Kinesin Family Member Genes Expression in Patients with Breast Cancer.

BACKGROUND This study investigated the diagnostic and prognostic values of kinesin superfamily proteins (KIFs) in breast cancer (BC) patients. MATERIAL AND METHODS All data were obtained from the Cancer Genome Atlas. DESeq was run to test for differentially expressed KIF genes. Patients were divided into high- and low-expression groups according to the median expression values of each KIF genes. Survival data were calculated using the Cox proportional hazard model. Comprehensive survival analysis was performed to evaluate the prognostic value of the prognostic signature. Gene set enrichment analysis (GSEA) was conducted to identify associated gene ontology and KEGG pathways. RESULTS Bioinformatics analysis showed that all KIF genes were significantly enriched during DNA replication and the cell cycle, and co-expressed with each other. Thirteen KIF genes were differentially expressed in cancer and adjacent tissues, and high levels of KIF15, KIF20A, KIF23, KIF2C and KIF4A genes were significantly correlated with poor overall survival (OS). GSEA showed that BC patients with high expression of KIF15, KIF20A, KIF23, KIF2C and KIF4A were enriched in the cell cycle process, P53 regulation pathway and mismatch repair. Combinations of low expression of KIF15, KIF20A, KIF23, KIF2C and KIF4A were more highly correlated with favorable OS. Nomograms showed that the KIF4A risk score provided the maximum number of risk points (range 0-100), whereas other genes made a lower contribution. CONCLUSIONS We conclude that 13 KIF genes are differentially expressed in BC tumor tissues, and KIF15, KIF20A, KIF23, KIF2C and KIF4A are associated with prognostic factors in BC.

Water and Sediment Microbial Quality of Mountain and Agricultural Streams.

Increased public health risk caused by pathogen contamination in streams is a serious issue, and mitigating the risk requires improvement in existing microbial monitoring of streams. To improve understanding of microbial contamination in streams, we monitored in stream water columns and streambed sediment. Two distinct streams and their subwatersheds were studied: (i) a mountain stream (Merced River, California), which represents pristine and wild conditions, and (ii) an agricultural stream (Squaw Creek, Iowa), which represents an agricultural setting (i.e., crop, manure application, cattle access). Stream water column and sediment samples were collected in multiple locations in the Merced River and Squaw Creek watersheds. Compared with the mountain stream, water column concentrations in the agricultural stream were considerably higher. In both mountain and agricultural streams, concentrations in bed sediment were higher than the water column, and principal component analysis indicates that land use affected water column levels significantly ( < 0.05). The cluster analysis showed grouping of subwatersheds for each basin, indicating unique land use features of each watershed. In general, water column levels in the mountain stream were lower than the USEPA's existing water quality criteria for bacteria. However, the levels in the agricultural stream exceeded the USEPA's microbial water quality criteria by several fold, which substantiated that increased agricultural activities, use of animal waste as fertilizers, and combined effect of rainfall and temperature may act as potential determining factors behind the elevated levels in agriculture streams.

[Cultural regionalization for Notopterygium incisum based on 3S technology platform. I. Evaluation for growth suitability for N. incisum based on ecological factors analysis by Maxent and ArcGIS model].

Growth suitability as assessment indicators for medicinal plants cultivation was proposed based on chemical quality determination and ecological factors analysis by Maxent and ArcGIS model. Notopterygium incisum, an endangered Chinese medicinal plant, was analyzed as a case, its potential distribution areas at different suitability grade and regionalization map were formulated based on growth suitability theory. The results showed that the most suitable habitats is Sichuan province, and more than 60% of the most suitable areawas located in the western Sichuan such as Aba and Ganzi prefectures for N. incisum. The results indicated that habitat altitude, average air temperature in September, and vegetation types were the dominant factors contributing to the grade of plant growth, precipitation and slope were the major factors contributing to notopterol accumulation in its underground parts, while isoimperatorin in its underground parts was negatively corelated with precipitation and slope of its habitat. However, slope as a factor influencing chemical components seemed to be a pseudo corelationship. Therefore, there were distinguishing differences between growth suitability and quality suitability for medicinal plants, which was helpful to further research and practice of cultivation regionalization, wild resource monitoring and large-scale cultivation of traditional Chinese medicine plants.

Overexpression of E2F1 in human gastric carcinoma is involved in anti-cancer drug resistance.

BACKGROUND: Routine chemotherapy often cannot achieve good therapeutic effects because of multidrug resistance (MDR). MDR is frequently caused by the elevated expression of the MDR1 gene encoding P-glycoprotein (P-gp). E2F1 is a frequently overexpressed protein in human tumor cells that increases the activity of the MDR1 promoter, resulting in higher P-gp levels. The upregulation of P-gp might contribute to the survival of tumor cells during chemotherapy. E2F1 confers anticancer drug resistance; however, we speculate whether E2F1 affects MDR through other pathways. This study investigated the possible involvement of E2F1 in anticancer drug resistance of gastric carcinoma in vitro and in vivo. METHODS: A cisplatin-resistant SGC7901/DDP gastric cancer cell line with stable overexpression of E2F1 was established. Protein expression levels of E2F1, MDR1, MRP, TAp73, GAX, ZEB1, and ZEB2 were detected by western blotting. The influence of overexpression of E2F1 on anticancer drug resistance was assessed by measuring IC50 of SGC7901/DDP cells to cisplatin, doxorubicin, and 5-fluorouracil, as well as the rate of doxorubicin efflux, apoptosis, and cell cycle progression detected by flow cytometry. We determined the in vivo effects of E2F1-overexpression on tumor size in nude mice, and apoptotic cells in tumor tissues were detected by deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling and hematoxylin and eosin staining. RESULTS: The SGC7901/DDP gastric cancer cell line stably overexpressing E2F1 exhibited significantly inhibited sensitivity to cisplatin, doxorubicin, and 5-fluorouracil. Flow cytometry confirmed that the percentage of apoptotic cells decreased after E2F1 upregulation, and that upregulation of E2F1 potentiated S phase arrest of the cell cycle. Furthermore, upregulation of E2F1 significantly decreased intracellular accumulation of doxorubicin. Western blot revealed that E2F1 upregulation suppressed expression of GAX, and increased the expression of MDR1, MRP, ZEB1, TAp73, and ZEB2. CONCLUSIONS: Overexpression of E2F1 promotes the development of MDR in gastric carcinoma, suggesting that E2F1 may represent an efficacious target for gastric cancer therapy.

Large eddy simulation on wind-induced interference effects of staggered chamfered square cylinders.

Chamfered corners in buildings are the main means to reduce the control effect of wind load on the structure, and the interference effect of chamfered buildings cannot be ignored. At present, only the mutual interference coefficients of square and rectangular section buildings are given in the Chinese code, without the interference effect of chamfered buildings being specified. Therefore, in this paper, aerodynamic force and wind pressure coefficients of chamfered square cylinders of different spacing are obtained by the large eddy simulation method. Wind load characteristics, non-Gaussian characteristics and interference effects of chamfered square cylinders with different arrangements are studied based on aerodynamic coefficients, wind pressure coefficients and interference coefficients. The results show that when the wall y plus value is 1, the large eddy simulation is the most accurate to simulate the wind load and wind field parameters. Besides, the aerodynamic effects, non-Gaussian characteristics and interference effects between the chamfered square cylinders are mainly controlled by the cross-wind interval and the spacing (4.0, 4.0) is the characteristic coordinate. That means, when the spacing is smaller than this coordinate, the interference effect of the square cylinder is more obvious. When the spacing coordinate is greater than (4.0, 4.0), the aerodynamic coefficients and non-Gaussian regional distributions of the principal square cylinder and the isolated cylinder are the same, and the interference factor approaches 1.

Biomimetic cytomembrane-coated ZIF-8-loaded DMDD nanoparticle and sonodynamic co-therapy for cancer.

Background: Breast cancer (BC) is the most common type of cancer affecting females. It is also a leading cause of cancer-related death in women worldwide. Methods: Sonodynamic therapy (SDT) is an emerging therapeutic strategy for cancer treatment. SDT ensures non-invasive penetration of deep tumors and results in activation of non-toxic sonosensitizers administered in deep tumor sites to become cytotoxic. It has been reported that 2-dodecyl-6-methoxycyclohexa-2,5-diene-1,4-dione (DMDD) has a significant anti-tumor effect against various cancer types including BC. However, DMDD is hydrophobic. Therefore, a one-step encapsulation method was used in the current study to construct zeolitic imidazole frameworks-8 (ZIF-8) loaded with DMDD and sonosensitizer chlorin e6 (Ce6). ZIF-8 was further modified by coating it with a biomimetic cell membrane to improve targeted delivery. Results: In vitro and in vivo results indicated that the nanomedicines had great biocompatibility properties and targeting ability. The nanocomposite exhibited a higher release rate under an acidic tumor microenvironment. The tumor killing effect of reactive oxygen species (ROS) generated from Ce6 and inhibition of tumor growth was enhanced after ultrasound (US) treatment, which might be caused by the increase in apoptosis rate. Conclusions: These findings show that the combination of nanomedicine and SDT provides a potential therapeutic method for BC.

Biomimetic Metal-Organic Framework Nanoparticles for Synergistic Combining of SDT-Chemotherapy Induce Pyroptosis in Gastric Cancer.

In recent years, sonodynamic therapy (SDT) has been widely developed for cancer research as a promising non-invasive therapeutic strategy. Here, we synthesized zeolitic imidazole frameworks-8 (ZIF-8) and utilized its properties to encapsulate hydrophobic Chlorin e6 (Ce6) and hydrophilic tirapazamine (TPZ) for a synergistic sonodynamic chemotherapy, which was also accompanied by the modification of cytomembrane of gastric cancer (GC) cells. Thus, we enabled the biomimetic property to achieve targeted delivery. Ce6-mediated SDT, in combination with ultrasound irradiation, could target the release of reactive oxygen species (ROS) to aggravate further hypoxia and activate TPZ. Combining these effects could induce the pyroptosis of GC cells and play the anti-tumor function, which could provide a potential therapeutic method for cancer therapy.

Circular RNA Profiling Reveals That circRNA_104433 Regulates Cell Growth by Targeting miR-497-5p in Gastric Cancer.

BACKGROUND: The role and mechanism of hsa_circRNA_104433 in gastric cancer (GC) are further elucidated. MATERIALS AND METHODS: CircRNA_104433 was selected by circRNA microarrays and GEO database. qRT-PCR was used to analyze the expression of circRNA_104433 in GC. The role of circRNA_104433 in GC cells was evaluated based on cell cycle progression, cell proliferation, cell apoptosis, and tumor xenograft experiment assay. To explore the mechanisms of circRNA_104433 in GC TCGA database, STRING version, qRT-PCR and luciferase assay were performed. Furthermore, the prognostic value of CDC25A in GC was determined based on the GEO database. RESULTS: The level of circRNA_104433 showed upregulation in GC tissues, and the expression of it showed a positive correlation with the degree of differentiation and the size of the tumor. Knockdown of circRNA_104433 inhibited cell cycle transition, and cell proliferation, while promoted cell apoptosis in GC. CircRNA_104433 directly binds to miR-497-5p, which directly regulates CDC25A. The median survival period of GC patients with high expression levels of CDC25A was 21.3 months, which was shorter than those with low group expression of CDC25A (35.9 months). The cell cycle proteins CDK1, CDK2, CCNB1, PKMYT1, CDC20, CHEK1 and CDC25A were coexpressed with CDC25A. CONCLUSION: These findings suggested that knockdown of circRNA_104433 expression suppressed tumor development in GC.

Development of a simple and high-yielding fed-batch process for the production of porcine circovirus type 2 virus-like particle subunit vaccine.

The cap protein is encoded by the orf2 gene of porcine circovirus type 2 (PCV2) has the main antigen epitope of PCV2 and can form virus-like particles (VLPs), which are expressed in insect cells. PCV2-VLPs can effectively inhibit PCV2 replication as a subunit vaccine. In this study, a robust and reliable fed-batch process was successfully developed for the production of PCV2-VLPs by Sf9 cells. The feeding solution, feeding strategy, and cell density at infection were optimized to maximize the final PCV2-VLPs production yields. The cell density at infection and the volumetric PCV2-VLPs production reached 12 × 106 cells/mL and 110 mg/L, respectively, which yielded 3- and 3.6-fold enhancements compared to the batch culture. The PCV2-VLPs produced in fed-batch culture were not different from the PCV2-VLPs produced in a batch culture in an immunity test. A highly efficient production process was produced for PCV2-VLPs subunit vaccines, which could provide an effective means for the industrial production of PCV2 vaccines.

MiR-1284 suppresses gastric cancer progression by targeting EIF4A1.

Background: MicroRNAs (miRNAs) play a key role in the development of gastric cancer (GC). MiRNA arrays showed that lymph node metastasis in GC is correlated with the expression of miR-1284. Although its function and mechanisms in GC have not been fully described, the regulation of EIF4A1 by miR-1284 and its role in drug-resistant GC has been reported in our previous studies. Methods: qRT-PCR was used to study the level of miR-1284 expression in GC cell lines and tissues. Subsequently, the CCK-8 assay was used to detect cell proliferation, while transwell assay was used to detect invasion and migration of the GC cells. Flow cytometry was used to detect the effect of miR-1284 on GC cells in vivo by building subcutaneous GC nude mice transplantation tumor model. In addition, the influence of miR-1284 gene expression profile in SGC-7901 cells was detected by total gene expression chip, and the target gene of miR-1284 was detected by luciferase reporter assay, qRT-PCR, and western blotting. Results: The miR-1284 level was down-regulated in GC tssues and cell lines. MiR-1284 was significantly associated with tumor size, degree of differentiation and patients' distant metastasis. MiR-1284 inhibited invasion, migration, and proliferation of GC cells. During the G1/S phase, miR-1284 arrested the cycle of GC cells in vitro. MiR-1284 also suppressed tumor from growing and metastasizing in xenograft models as well as influenced the gene expression profile in SGC-7901 cells. Also, EIF4A1 was the direct target gene for miR-1284. Further, an inverse correlation between the miR-1284 expression and EIF4A1 was found in GC tissues. Over-expressed miR-1284 decreased c-Myc, MMP12, JUN expression, while increased CDH1 expression. Conclusion: These data suggested that miR-1284 acts as a tumor suppressor, and directly blocked EIF4A1 in GC.

Regulation of drug resistance and metastasis of gastric cancer cells via the microRNA647-ANK2 axis.

Due to a lack of effective methods for early diagnosis, the majority of patients with gastric cancer (GC) are diagnosed during the late stages of the disease, which are often accompanied by metastasis. For these patients, despite being considered an important therapeutic modality in the treatment of cancer, chemotherapy is usually not effective due to multidrug resistance (MDR). The expression levels of MDR/metastasis­associated genes are regulated by numerous microRNAs (miRNAs/miRs). The expression of miR-647 in GC tissues and SGC7901/VCR cell line (drug resistance to vincristine) was detected by qRT-PCR. The effect of overexpression of miR-647 on drug resistance was evaluated by measuring the half maximal inhibitory concentration (IC50) value of SGC-7901/VCR to vincristine and tumor growth in vivo. Moreover, drug-induced cell apoptosis and cell cycle were evaluated by flow cytometry, as well as the ability of cell migration and invasiveness detected by wound healing and transwell assay. Furthermore, underlying targets of miR-647 were predicted by TargetScan and MicroRNA; meanwhile, the expression of ANK2, FAK, MMP2, MMP12,CD44,SNAIL1 were observed by qRT-PCR and western blot analysis. The present study established that the expression levels of miR­647 were downregulated in GC tissues from patients with metastasis and in the vincristine­resistant SGC7901 (SGC­7901/VCR) GC cell line. The IC50 value for vincristine was significantly decreased, whereas the proportion of cells in G0/G1 phase and the drug­induced apoptotic rate were significantly increased following upregulation of miR­647. Furthermore, the results demonstrated that miR­647 overexpression led to decreased migration and invasion of SGC­7901/VCR cells. Overexpression of miR­647 was also demonstrated to sensitize tumors to chemotherapy in vivo. In addition, miR­647 overexpression was able to reduce the expression levels of ankyrin­B, focal adhesion kinase, matrix metalloproteinase (MMP)2, MMP12, cluster of differentiation 44 and snail family transcriptional repressor 1. In conclusion, these findings demonstrated that miR­647 may function as a novel target to ameliorate drug resistance and metastasis of GC cells.

Regulation of cell proliferation and metastasis by microRNA-593-5p in human gastric cancer.

BACKGROUND: MicroRNA (miRNA) array analysis has reported that the expression of miR-593-5p is associated with lymph node metastasis in gastric cancer (GC); however, the function and mechanism of miR-593-5p in GC have not been described yet. miR-593-5p has also not been elucidated widely in other cancers. METHODS: miR-593-5p expression was detected by quantitative RT-PCR (qRT-PCR) in human GC tissues and cell lines. Cell proliferation was investigated using CCK-8 assays, cell cycle was detected by flow cytometric method, and cell migration and invasion abilities were evaluated by wound-healing and transwell assays. miR-593-5p-influenced gene expression profiles were detected by total gene expression chip method in MGC-803 cells, and miR-593-5p candidate target genes were predicted using bioinformatics methods. The candidate target gene and downstream of miR-593-5p were determined by qRT-PCR, Western blot, and dual-luciferase reporter assays. The effects of miR-593-5p on the growth and metastasis of GC were evaluated by tumor xenograft experiment in vivo. RESULTS: miR-593-5p was frequently downregulated in GC patients and GC cell lines. miR-593-5p was significantly correlated with tumor size and distant metastasis in GC patients. miR-593-5p inhibited cell proliferation, migration, and invasion and also arrested cell cycle at the G0/G1 phase in SGC-7901 and MGC-803 cells in vitro. miR-593-5p also suppressed tumor growth and metastasis in vivo. miR-593-5p influenced gene expression profile in MGC-803 cells. MST4 was indirectly targeted by miR-593-5p. miR-593-5p also downregulated FAK, MMP12, and JUN protein expression. CONCLUSION: Our study suggests that miR-593-5p may function as a tumor suppressor in GC through a mechanism that regulates JUN pathway via indirectly targeting the MST4 gene.

Role of miR-647 in human gastric cancer suppression.

MicroRNAs (miRNAs) regulate various oncogenes concomitantly, resulting in tumor suppression. They regulate proliferation and migration pathways in tumor development, suggesting a potential therapeutic role. In the present study, we found that miR-647 was markedly downregulated in gastric cancer (GC), and was significantly correlated with reduced tumor size and metastasis. In addition, miR-647 was also reduced in GC cell lines. Furthermore, overexpression of miR-647 in the GC cell lines inhibited cell proliferation, promoted cell cycle arrest at the G0/G1 phase and induced cell apoptosis. miR-647 also significantly inhibited tumor growth in vivo. Notably, we found that miR-647 overexpression suppressed the migration and invasion of the cancer cells, particularly liver metastasis in nude mice. miR-647 also reduced the expression levels of genes associated with proliferation and metastasis in tumors, including ANK2, FAK, MMP2, MMP12, CD44 and SNAIL1. Overall, our findings demonstrated that miR-647 exerts powerful antitumorigenic effects in vitro and in vivo, and may represent a promising therapeutic agent against GC.

MiR-1284 modulates multidrug resistance of gastric cancer cells by targeting EIF4A1.

Routine chemotherapy as an important treatment mode often can not be effective because of multidrug resistance (MDR). MicroRNA (miRNA) modulates the expression of a great number of genes, including MDR. In this study, the expression of miR-1284 was reduced in gastric cancer (GC) tissue specimens with metastasis and in vincristine-resistant (VCR) GC SGC7901 cells (SGC-7901/VCR) compared to that in the controls. Recombinant lentiviral vectors with miR-1284 led to the overexpression of miR-1284 mRNA and reversed the chemoresistance of SGC7901/VCR cells, promoted cell cycle arrested at the G0/G1 phase, accelerated drug-induced apoptosis, and decreased migration and invasiveness of SGC-7901/VCR. In addition, the overexpression of miR-1284 sensitized tumors to chemotherapy in vivo. Our data provide combined evidence that miR-1284 can heighten the expression of MYC and reduce the expression of JUN, MMP12, and EIF4A1 that was the direct target. In conclusion, miR-1284 can function as a new regulator to reduce GC MDR cells by targeting EIF4A1.

Construction of a novel, stable, food-grade expression system by engineering the endogenous toxin-antitoxin system in Bacillus subtilis.

Bacillus subtilis as an important workhorse that has been widely used to produce enzymes and metabolites. To broaden its applications, especially in the food and feed industry, we constructed a novel, stable, food-grade expression system by engineering its type II toxin-antitoxin system. The expression of the toxin EndoA, encoded by the chromosomal ydcE gene, was regulated by an endogenous, xylose-inducible promoter, while the ydcD gene, which encodes the unstable antitoxin EndoB, was inserted into a food-grade vector backbone, where its expression was driven by the native, constitutive promoter PylxM. By maintaining the xylose concentration above 2.0 g L(-1), this auto-regulated expression system was absolutely stable after 100 generations. Compared with traditional antibiotic-dependent expression systems, this novel expression system resulted in greater biomass and higher titers of desired products (enzymes or metabolites). Our results demonstrate that this stable, food-grade expression system is suitable for enzyme production and pathway engineering, especially for the production of food-grade enzymes and metabolites.

Assessing the changes in E. coli levels and nutrient dynamics during vermicomposting of food waste under lab and field scale conditions.

Vermicomposting (VC) has proven to be a promising method for treating garden, household, and municipal wastes. Although the VC has been used extensively for converting wastes into fertilizers, pathogens such as Escherichia coli (E. coli) survival during this process is not well documented. In this study, both lab and field scale experiments were conducted assessing the impacts of earthworms in reducing E. coli concentration during VC of food waste. In addition, other pertinent parameters such as temperature, carbon and nitrogen content, moisture content, pH, volatile solids, micronutrients (P, K, Ca, Mg, and S), and heavy metals (Zn, Mn, Fe, and Cu) were monitored during the study. The lab and field scale experiments were conducted for 107 and 103 days, respectively. The carbon to nitrogen ratio (C/N) decreased by 54 % in the lab scale study and by 36 % in the field study. Results showed that VC was not significantly effective in reducing E. coli levels in food waste under both lab and field scale settings. The carbon to nitrogen ratio (C/N) decreased by 54 % in the lab scale study and by 36 % in the field study.

Overexpression of CDX2 in gastric cancer cells promotes the development of multidrug resistance.

Modulator of multidrug resistance (MDR) gene is a direct transcriptional target of CDX2. However, we still speculate whether CDX2 affects MDR through other ways. In this study, a cisplatin-resistant (SGC7901/DDP) and a 5-fluoro-2, 4(1h,3h)pyrimidinedione-resistant (BGC823/5-FU) gastric cancer cell line with stable overexpression of CDX2 were established. The influence of overexpression of CDX2 on MDR was assessed by measuring IC50 of SGC7901/DDP and BGC823/5-FU cells to cisplatin, doxorubicin, and 5-fluorouracil, rate of doxorubicin efflux, apoptosis, and cell cycle progression detected by flow cytometry. In addition, we determined the in vivo effects of CDX2-overexpression lentiviral vector (LV-CDX2-GFP) on tumor size, and apoptotic cells in tumor tissues were detected by deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling and hematoxylin and eosin staining. Results showed that LV-CDX2-GFP led to up-regulation of CDX2 mRNA and protein expression. It significantly inhibited the sensitivity of SGC7901/DDP and BGC823/5-FU cells to cisplatin, doxorubicin, and 5-fluorouracil. Flow cytometry confirmed that the percentage of apoptotic cells decreased after CDX2 up-regulation. This notion was further supported by the observation that up-regulation of CDX2 blocked entry into the M-phase of the cell cycle. Furthermore, up-regulation of CDX2 significantly decreased intracellular accumulation of doxorubicin. In molecular studies, quantitative reverse-transcriptase real-time polymerase chain reaction and western blotting revealed that CDX2 up-regulation could suppress expression of Caspase-3, Caspase-9 and PTEN, and increased the expression of MDR1, MRP, mTOR, HIF-1α.

Overexpression of caudal type homeobox transcription factor 2 inhibits the growth of the MGC-803 human gastric cancer cell line in vivo.

Caudal type homeobox transcription factor 2 (CDX2) is important in intestinal cell fate specification and multiple lines of evidence have substantiated that CDX2 is important in carcinogenesis of the digestive tract. The CDX2 regulatory network is intricate and remains to be fully elucidated in gastric cancer. The aim of the present study was to examine the effects of CDX2 on the growth of the MGC-803 human gastric cancer cell line in vivo, and to elucidate the mechanism involved. The effects of the overexpression of CDX2 in xenograft tumors of MGC-803 cells was investigated in nude mice through the injection of CDX2 recombinant lentiviral vectors. The tumor size was measured using vernier callipers. The expression levels of CDX2, survivin, B-cell lymphoma 2 (Bcl-2), Bcl-2-associated X protein (Bax), cyclin D1, s-phase kinase-associated protein 2 (Skp2) and c-Myc in the tumor cells were analyzed by western blotting and semi-quantitative reverse transcription polymerase chain reaction. The apoptotic rates were determined using a terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling assay. The overexpression of CDX2 was observed in the group subjected to the injection of CDX2 recombinant lentiviral vectors. CDX2 had an inhibitory effect on the MGC-803 human gastric cancer cell line and promoted tumor cell apoptosis in vivo. Furthermore, the overexpression of CDX2 upregulated the expression of Bax and downregulated the expression levels of survivin, Bcl-2, cyclin D1, Skp2 and c-Myc in the tumor tissues. These results indicated that CDX2 may serve as a tumor suppressor in gastric cancer, and inhibits gastric cancer cell growth by suppressing the nuclear factor-κB signaling pathway.