Population genetic variation and geographic distribution of suitable areas of Coptis species in China.

Introduction: The rhizomes of Coptis plants have been used in traditional Chinese medicine over 2000 years. Due to increasing market demand, the overexploitation of wild populations, habitat degradation and indiscriminate artificial cultivation of Coptis species have severely damaged the native germplasms of species in China. Methods: Genome-wide simple-sequence repeat (SSR) markers were developed using the genomic data of C. chinensis. Population genetic diversity and structure of 345 Coptis accessions collected from 32 different populations were performed based on these SSRs. The distribution of suitable areas for three taxa in China was predicted and the effects of environmental variables on genetic diversity in relation to different population distributions were further analyzed. Results: 22 primer pairs were selected as clear, stable, and polymorphic SSR markers. These had an average of 16.41 alleles and an average polymorphism information content (PIC) value of 0.664. In the neighbor-joining (N-J) clustering analysis, the 345 individuals clustered into three groups, with C. chinensis, C. chinensis var. brevisepala and C. teeta being clearly separated. All C. chinensis accessions were further divided into four subgroups in the population structure analysis. The predicted distributions of suitable areas and the environmental variables shaping these distributions varied considerably among the three species. Discussion: Overall, the amount of solar radiation, precipitation and altitude were the most important environmental variables influencing the distribution and genetic variation of three species. The findings will provide key information to guide the conservation of genetic resources and construction of a core reserve for species.

Analysis of widely targeted metabolites of quinoa sprouts (Chenopodium quinoa Willd.) under saline-alkali stress provides new insights into nutritional value.

Quinoa sprouts are a green vegetable rich in bioactive chemicals, which have multiple health benefits. However, there is limited information on the overall metabolic profiles of quinoa sprouts and the metabolite changes caused by saline-alkali stress. Here, a UHPLC-MS/MS-based widely targeted metabolomics technique was performed to comprehensively evaluate the metabolic profiles of quinoa sprouts and characterize its metabolic response to saline-alkali stress. A total of 930 metabolites were identified of which 232 showed significant response to saline-alkali stress. The contents of lipids and amino acids were significantly increased, while the contents of flavonoids and phenolic acids were significantly reduced under saline-alkali stress. Moreover, the antioxidant activities of quinoa sprouts were significantly affected by saline-alkali stress. The enrichment analysis of the differentially accumulated metabolites revealed that flavonoid, amino acid and carbohydrate biosynthesis/metabolism pathways responded to saline-alkali stress. This study provided an important theoretical basis for evaluating the nutritional value of quinoa sprouts and the changes in metabolites in response to saline-alkali stress.

Gene identification and semisynthesis of the anti-inflammatory oleanane-type triterpenoid wilforlide A.

Wilforlide A is one of the main active constituents produced in trace amounts in Tripterygium wilfordii Hook F, which has excellent anti-inflammatory and immune suppressive effects. Despite the seeming structural simplicity of the compound, the biosynthetic pathway of wilforlide A remains unknown. Gene-specific expression analysis and genome mining were used to identify the gene candidates, and their functions were studied in vitro and in vivo. A modularized two-step (M2S) technique and CRISPR-Cas9 methods were used to construct engineering yeast. Here, we identified a cytochrome P450, TwCYP82AS1, that catalyses C-22 hydroxylation during wilforlide A biosynthesis. We also found that TwCYP712K1 to K3 can further oxidize the C-29 carboxylation of oleanane-type triterpenes in addition to friedelane-type triterpenes. Reconstitution of the biosynthetic pathway in engineered yeast increased the precursor supply, and combining TwCYP82AS1 and TwCYP712Ks produced abrusgenic acid, which was briefly acidified to achieve the semisynthesis of wilforlide A. Our work presents an alternative metabolic engineering approach for obtaining wilforlide A without relying on extraction from plants.

Structural and Catalytic Insight into the Unique Pentacyclic Triterpene Synthase TwOSC.

The oxidosqualene cyclase (OSC) catalyzed cyclization of the linear substrate (3S)-2,3-oxidosqualene to form diverse pentacyclic triterpenoid (PT) skeletons is one of the most complex reactions in nature. Friedelin has a unique PT skeleton involving a fascinating nine-step cation shuttle run (CSR) cascade rearrangement reaction, in which the carbocation formed at C2 moves to the other side of the skeleton, runs back to C3 to yield a friedelin cation, which is finally deprotonated. However, as crystal structure data of plant OSCs are lacking, it remains unknown why the CSR cascade reactions occur in friedelin biosynthesis, as does the exact catalytic mechanism of the CSR. In this study, we determined the first cryogenic electron microscopy structure of a plant OSC, friedelin synthase, from Tripterygium wilfordii Hook. f (TwOSC). We also performed quantum mechanics/molecular mechanics simulations to reveal the energy profile for the CSR cascade reaction and identify key residues crucial for PT skeleton formation. Furthermore, we semirationally designed two TwOSC mutants, which significantly improved the yields of friedelin and ß-amyrin, respectively.

CYP72D19 from Tripterygium wilfordii catalyzes C-2 hydroxylation of abietane-type diterpenoids.

KEY MESSAGE: CYP72D19, the first functional gene of the CYP72D subfamily, catalyzes the C-2 hydroxylation of abietane-type diterpenoids. The abietane-type diterpenoids, e.g., triptolide, tripdiolide, and 2-epitripdiolide, are the main natural products for the anti-tumor, anti-inflammatory, and immunosuppressive activities of Tripterygium wilfordii, while their biosynthetic pathways are not resolved. Here, we cloned and characterized the CYP72D19-catalyzed C-2 hydroxylation of dehydroabietic acid, a compound that has been proven to be a biosynthetic intermediate in triptolide biosynthesis. Through molecular docking and site-directed mutagenesis, L386, L387, and I493 near the active pocket were found to have an important effect on the enzyme activity, which also indicates that steric hindrance of residues plays an important role in function. In addition, CYP72D19 also catalyzed a variety of abietane-type diterpenoids with benzene ring, presumably because the benzene ring of the substrate molecule stabilized the C-ring, allowing the protein and the substrate to form a relatively stable spatial structure. This is the first demonstration of CYP72D subfamily gene function. Our research provides important genetic elements for the structural modification of active ingredients and the heterologous production of other 2-hydroxyl abietane-type natural products.

Patellar instability-induced bone loss in the femoral trochlea is associated with the activation of the JAK1/STAT3 signaling pathway in growing mice.

INTRODUCTION: Patellar instability (PI) at an early age is believed closely correlated with bone loss in the development of the femoral trochlea and can cause trochlear dysplasia. However, the molecular mechanism of PI-induced bone loss has not been established. The Janus kinase (JAK)/signal transducers and activators of transcription (STAT) signaling pathway plays an important role in bone development by regulating the expression of osteoprotegerin (OPG) and receptor activator of nuclear factor kappa B ligand (RANKL). The aim of this study was to explore the association of JAK1/STAT3 signaling to PI-induced subchondral bone loss in the femoral trochlea. METHODS: Four-week-old male C57BL/6 mice were randomly divided into two groups (n = 50/group). Mice in the experimental group underwent surgery to induce PI. Distal femurs were collected 2 and 4 weeks after surgery (n = 25 knees/each time point, each group). Microcomputed tomography and histological observations were performed to investigate the morphology of the femoral trochlea and changes in bone mass. qPCR, western blot, and immunohistochemistry analyses were performed to evaluate the expression of JAK1, STAT3, RANKL, and OPG in subchondral bone. A t test was performed for the statistical analysis; a P value < 0.05 was considered to be statistically significant. RESULTS: In the experimental group, subchondral bone loss in the femoral trochlea was observed two and four weeks after PI; morphological changes, such as a flatter trochlear groove and an increased sulcus angle, were observed in the femoral trochlea; qPCR, western blot, and immunohistochemistry analyses showed higher expression of JAK1, STAT3, and RANKL and lower expression of OPG (P < 0.05). CONCLUSION: PI-induced subchondral bone loss in the femoral trochlea and resulted in trochlear dysplasia in growing mice. This bone loss is associated with activation of the JAK1/STAT3 signaling pathway, which weakens the function of osteoblasts and stimulates both formation and function of osteoclasts.

[Spatio-temporal Characteristics of Organic Aggregates and the Driving Factors in Typical Lakes].

Organic aggregates (OA) are the important circulation hub of matter and energy in aquatic ecosystems. However, the comparison studies on OA in lakes with different nutrient levels are limited. In this study, spatio-temporal abundances of OA and OA-attached bacteria (OAB) in oligotrophic Lake Fuxian, mesotrophic Lake Tianmu, middle-eutrophic Lake Taihu, and hyper-eutrophic Lake Xingyun were investigated in different seasons during 2019-2021 using a scanning electron microscope, epi-fluorescence microscope, and flow cytometry. The results showed that:① the annual average abundances of OA in Lake Fuxian, Lake Tianmu, Lake Taihu, and Lake Xingyun were 1.4×104, 7.0×104, 27.7×104, and 16.0×104 ind·mL-1, whereas the annual average abundances of OAB in the four lakes were 0.3×106, 1.9×106, 4.9×106, and 6.2×106 cells·mL-1. The ratios of OAB:total bacteria (TB) in the four lakes were 30%, 31%, 50%, and 38%, respectively. ② OA abundance in summer was significantly higher than that in autumn and winter; however, the ratio of OAB:TB in summer was approximately 26%, which was significantly lower than that in the other three seasons. ③ Lake nutrient status was the most important environmental factor that affected the abundance variations of OA and OAB, accounting for 50% and 68% of the spatio-temporal variations in OA and OAB abundances. ④ Nutrient and organic matters were enriched in OA, especially in Lake Xingyun; the proportions of particle phosphorous, particle nitrogen, and organic matters in this lake were as high as 69%, 59%, and 79%, respectively. Under the circumstance of future climate change and the expansion of lake algal blooms, the effects of algal-originated OA in the degradation of organic matters and nutrient recycling would be increased.

Patterns of free-living and particle-attached bacteria along environmental gradients in Lake Taihu.

To elucidate the effects of environmental heterogeneity on diversity, composition, and degree of overlap between free-living (FL) and particle-attached (PA) bacteria, we sampled large, shallow, eutrophic Lake Taihu, China across gradients spanning riverine inflow, cyanobacterial blooms, and the open limnetic area. Using high-throughput sequencing of the 16S rRNA gene, we show that (i) bacterial communities near riverine inflow had high α-diversity and a high degree of overlap between FL and PA lifestyles, (ii) communities in cyanobacterial blooms have reduced α-diversity within the PA lifestyle, and (iii) communities from the limnetic area had the lowest bacterial α-diversity within the FL lifestyle and a medium degree of overlap between the FL and PA lifestyles. Redundancy analysis showed that the variation of the FL bacterial community was shaped by suspended solids and total phosphorous, while the variation of the PA bacterial community was shaped by suspended solids, dissolved oxygen, and the percentage of organic matter in suspended solids. This study highlights the importance of environmental heterogeneity, riverine input, cyanobacterial blooms, and nutrient status on the spatial distribution patterns of FL and PA bacterial communities in freshwater lakes.

Effects of dissolved organic matter derived from chicken manure on the biotransformation of roxarsone in soil.

Roxarsone (3-nitro-4-hydroxyphenylarsonic acid, ROX), widely used as a livestock feed additive, is excreted untransformed in large concentrations. Accumulation of this manure in the open environment increases dissolved organic matter (DOM) and ROX in soil within the aeration zone. And microbial action plays a dominant role in the transformation of ROX. However, the specific effect of DOM on the biotransformation of ROX is not known. In this paper, we investigated the transformation rate, metabolite content, and microbial community response of ROX in soils with different DOM concentrations (71.61, 100, 200, 500, and 800 mg L-1). The transformation of ROX was consistent with first-order transformation kinetics. DOM promoted the transformation of ROX, and with high DOM (DOM ≥200 mg L-1), ROX was transformed almost completely within two days. In this case, DOM provided nutrients to microorganisms and promoted their growth, accelerating the transformation of ROX. Also, the solubility of ROX was enhanced by DOM to increase its bioavailability. The microbial diversity was negatively correlated with DOM concentration and ROX transformation time; during the transformation of ROX, Bacillus, Arthrobacter, Enterococcus, Acinetobacter, and Pseudomonas became dominant in the soil with anomalously high levels of DOM. This study demonstrates the transformation process of ROX under actual environmental conditions where organic matter coexists with ROX, and this understanding is important for the prevention and control of arsenic pollution in soil within the aeration zone with anomalously high levels of DOM.

Metabolomics Analysis Reveals the Differences Between Bupleurum chinense DC. and Bupleurum scorzonerifolium Willd.

Bupleurum chinense DC. and Bupleurum scorzonerifolium Willd. are two varieties of Bupleuri Radix in Chinese Pharmacopoeia 2020. The clinical efficacy of the two bupleurum species is different. The difference in clinical efficacy is closely related to the composition of plant metabolites. In order to analyze the difference in metabolites, we used liquid chromatography coupled with mass spectrometry (LC-MS) for untargeted metabolome and gas chromatography coupled with mass spectrometry (GC-MS) for widely targeted metabolome to detect the roots (R), stems (S), leaves (L), and flowers (F) of two varieties, and detected 1,818 metabolites in 25 classes. We performed a statistical analysis of metabolites. Differential metabolites were screened by fold-change and variable importance in the projection values of the OPLS-DA model, and significant differences were found among different groups. The content of active components (triterpenoid saponins) was found to be high in the BcR group than in the BsR group. Other pharmacological metabolites were significantly different. By Kyoto Encyclopedia of Genes and Genomes annotation and enrichment analysis, we found that differential metabolites of the aboveground parts mainly concentrated in monoterpenoid biosynthesis, while the differential metabolites of the root mainly concentrated in sesquiterpenoid and triterpenoid biosynthesis. Differences in metabolic networks may indirectly affect the metabolic profile of Bc and Bs, leading to differences in clinical efficacy. Our study provides a scientific basis for subsequent biosynthesis pathway and related bioactivity research, and provides a reference for developing non-medicinal parts and guiding the clinical application of Bupleuri Radix.

Efficient production of a cyclic dipeptide (cyclo-TA) using heterologous expression system of filamentous fungus Aspergillus oryzae.

BACKGROUND: Cyclic dipeptides are an important class of natural products owing to their structural diversity and biological activities. In fungi, the cyclo-ring system is formed through the condensation of two α-amino acids via non-ribosomal peptide synthetase (NRPS). However, there are few investigations on the functional identification of this enzyme. Additionally, information on how to increase the production of cyclic dipeptide molecules is relatively scarce. RESULTS: We isolated the Eurotium cristatum NWAFU-1 fungus from Jing-Wei Fu brick tea, whose fermentation metabolites contain echinulin-related cyclic dipeptide molecules. We cloned the cirC gene, encoding an NRPS, from E. Cristatum NWAFU-1 and transferred it into the heterologous host Aspergillus oryzae. This transformant produced a novel metabolite possessing an L-tryptophan-L-alanine cyclic dipeptide backbone (Cyclo-TA). Based on the results of heterologous expression and microsomal catalysis, CriC is the first NRPS characterized in fungi that catalyzes the formation of a cyclic dipeptide from L-tryptophan and L-alanine. After substrate feeding, the final yield reached 34 mg/L. In this study, we have characterized a novel NRPS and developed a new method for cyclic dipeptide production. CONCLUSIONS: In this study we successfully expressed the E. Cristatum NWAFU-1 criC gene in A. oryzae to efficiently produce cyclic dipeptide compounds. Our findings indicate that the A. oryzae heterologous expression system constitutes an efficient method for the biosynthesis of fungal Cyclic dipeptides.

Electrophysiological and pathological changes in the vastus medialis and vastus lateralis muscles after early patellar reduction and nerve growth factor injection in rabbits with patellar dislocation.

BACKGROUND: Patellar dislocation can cause a series of changes in the trochlear groove and patella. However, the influence of patellar dislocation on the medialis (VM) and vastus lateralis (VL) muscles and whether nerve growth factor (NGF) is beneficial to proprioceptive rehabilitation for patellar dislocation are unknown. The purpose of this study was to investigate the effects on VM and VL after the injection of NGF and early reduction in rabbits for patellar dislocation with electrophysiological and pathological analysis. METHODS: Sixty 2-month-old rabbits were randomly divided into four groups (15 rabbits in each group). Rabbits in Group 1, Group 2, and Group 3 underwent patellar dislocation surgery, and rabbits in Group 4 underwent sham surgery. One month later, patellar reduction was performed in Groups 1 and 2. NGF was injected into the rabbits of Group 1. The electrophysiological and pathological changes in VM and VL were analyzed at 1 month and 3 months after patellar reduction. RESULTS: The electrophysiological and pathological indices in Groups 1 and 2 were significantly different from those in Group 3 at 1 and 3 months after patellar reduction. There were significant differences between NGF injection Group 1 and Group 2 without NGF injection. There was no significant difference between Group 1 and Group 4 at 3 months after patellar reduction. CONCLUSIONS: Patellar dislocation can cause abnormal electrophysiological and pathological effects on VM and VL. Patellar reduction should be performed as early as possible, and NGF injection may be beneficial to the rehabilitation of proprioception.

Quinolone antibiotics enhance denitrifying anaerobic methane oxidation in Wetland sediments: Counterintuitive results.

Denitrifying anaerobic methane oxidation (DAMO) plays an important role in the element cycle of wetlands. In recent years, the content of antibiotics in wetlands has gradually increased due to human activities. However, the impact of antibiotics on the ecological function of DAMO remains unclear. Here we studied the influence of three high-content quinolone antibiotics (QNs) on DAMO in the sediments of the Baiyangdian Wetland. The results show that QNs can significantly promote the potential DAMO rates. Moreover, the enhancement of potential DAMO rates is positively correlated with the dosage of QNs. This promotion effect of QNs on nitrate-DAMO can be attributed to the hormesis phenomenon or their inhibition of substrate competitors. As antibacterial agents, QNs inhibit nitrite-DAMO conducted by bacteria, but greatly promote nitrate-DAMO conducted by archaea. These results suggest that the short-term effect of QNs on DAMO in wetlands is promotion rather than inhibition.

Biodegradable polyhydroxyalkanoates production from wheat straw by recombinant Halomonas elongata A1.

Waste straw bio-transformation of high value-added macromolecule polyhydroxyalkanoates (PHAs) was significance to environmental sustainable development. As a member of the PHA family, poly-ß-hydroxybutyrate (PHB) could be synthesized by Halomonas elongata A1 with maximal yields of 22.8% and 11.8% of bacterial weights using glucose and carboxymethyl cellulose as carbon sources, respectively. To improve PHB production, we generated three recombinant strains, the H. elongata P2 with highest PHB biosynthesis ability. When wheat straw, mixed substrate and oleic acid were individually used as single carbon source, the maximal PHA polymer accumulation in the H. elongata P2 reached 5.2%, 16.5% and 27.5%, respectively, after 84 h of cultivation. This hardness, toughness and crystallization properties of the PHA macromolecule altered dependent on starting substrates, when analyzed by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC). In terms of the hardness and roughness, the PHA produced from mixed substrates was much softer than that from wheat straw but harder than that from oleic acid. The long-chain carbon improved the softness and strength of the produced PHA. Our data indicate that economical substrates, such as straw and waste oil, can be used in the synthesis of multi-functional plastic products with biodegradable properties.

Complete chloroplast genome of Alternanthera philoxeroides by de novo sequencing.

Alternanthera philoxeroides (Mart.) Griseb. (Alternanthera philoxeroides) is an important herbage species, which could provide high-quality feed for livestock and poultry breeding. This paper is the first to report the A. philoxeroides's chloroplast genomes, which were detected by de novo sequencing. The results showed that the length of A. philoxeroides' chloroplast genome sequence was 152,255 bp, including a large single-copy (LSC) region (84,670 bp), a small single-copy (SSC) region (17,343 bp), and two inverted repeat (IR) regions (25,121 bp). Alternanthera philoxeroides' chloroplast genome encoded 132 genes including 8 rRNA, 38 tRNA, and 86 protein-coding genes. After phylogenetic and cluster analysis, A. philoxeroides was closest to Amaranthaceae, and the relationship between Amaranthus and Achyranthes was closest.

A modified slow sand filtration system of epikarst spring water in karst mountainous areas, China.

Epikarst springs are commonly used for drinking water in karst mountainous areas, but they tend to bring health risks to residents because of their vulnerability. In this work, a modified slow sand filtration system (M-SSF) was established as a case study to purify and conserve the epikarst spring water. The outcomes indicate that the purification of M-SSF relies mainly on the adsorption and ion exchange of the filter medium (mixtures of heat-treated red clay and crushed limestone, MHRCCL) during the schmutzdecke juvenility, and on the schmutzdecke-formed food chain of pollutants → bacteria → protozoa after the schmutzdecke maturity. The closed water cellar lined with ceramic tiles could reduce the deterioration of epikarst spring water during storage. Via 16S rRNA sequencing, it was found that the high abundance of TM6_Dependentiae in purified epikarst spring water (PESW) suggested that the M-SSF system relies on the formation of a closed food chain to achieve effective water purification. The decrease of Pseudarcicella abundance in PESW indicated that M-SSF could effectively prevent the water quality from external influences represented by leeches. Besides, the 16S function prediction was used to qualitatively characterize microbial nitrogen metabolism, as well as organic matter degradation in water purification.

Poly(3-hydroxypropionate): Biosynthesis Pathways and Malonyl-CoA Biosensor Material Properties.

Many single-use non-degradable plastics are a threat to life today, and several polyhydroxyalkanoates (PHAs) biopolymers have been developed in the bioplastic industry to place petrochemical-based plastics. One of such is the novel biomaterial poly(3-hydroxypropionate) [poly(3HP)] because of its biocompatibility, biodegradability, and high yield synthesis using engineered strains. To date, many bio-polymer-based functional composites have been developed to increase the value of raw microbial-biopolymers obtained from cheap sources. This review article broadly covers poly(3HP), a comprehensive summary of critical biosynthetic production pathways comparing the yields and titers achieved in different Microbial cell Factories. This article also provides extensive knowledge and highlights recent progress on biosensors' use to optimize poly(3HP) production, some bacteria host adopted for production, chemical and physical properties, life cycle assessment for poly(3HP) production using corn oil as carbon source, and some essential medical applications of poly(3HP).

Identifying watershed-scale spatiotemporal groundwater and surface water mixing function in the Yiluo River, Middle of China.

Researching the watershed-scale spatiotemporal groundwater and surface water mixing function, groundwater recharge heights and age can provide important information to watershed water sources management and water pollution controlling. In this study, 20 groundwater samples, 6 precipitation samples, and 40 surface water samples in the Yiluo River watershed in middle China were collected, and the mixing function between groundwater and surface water, recharge height, and age of groundwater was studied by using hydrochemistry (Cl, DO, EC, pH), radioactive isotopes (14C), and stable isotopes (13C, 18O, 15N). The results showed that river and shallow groundwater had frequent interaction. Evaporation function played a major role in the groundwater recharging process. Groundwater age displayed spatial and seasonal variations, and the age ranged from 660 to 2800 years (dry season) and 560 to 1800 years (wet season) in downstream and midstream, while the age range from 12,025 to 143,600 years (dry season) and 10,560 to 12,650 years (wet season) in upstream. The average recharge height of downstream and midstream both in dry and wet seasons is about 576.00 to 908.70 m. While in upstream, both, in the dry and wet seasons, ranged from 1285 to 2680 m. The mixing function between groundwater and surface water displayed spatiotemporal variety. These results of this study can provide useful information for the watershed-scale water resources management.

General anesthesia is not superior to sedation in clinical outcome and cost-effectiveness for ablation of persistent atrial fibrillation.

BACKGROUND: The strategy of anesthesia used during ablation of atrial fibrillation (AF) remains controversial. This study aimed to compare sedation with general anesthesia (GA) for catheter ablation of AF. HYPOTHESIS: The presence of AF is associated with an increased risk of stroke and heart failure and decreased quality of life and survival. METHODS: We carried out a retrospective single-centered study with 351 patients undergoing the first ablation procedure for AF under sedation or GA. The main outcome was freedom from recurrence of AF at 1 year. The total time of staying at the ablation laboratory and procedure cost were also calculated. RESULTS: Freedom from atrial arrhythmia and ablation time did not differ between AF patients under sedation and GA (77.9% vs 79.9% and 42.27 ± 9.84 minutes vs 41.51 ± 9.27 minutes, respectively), while the total procedure time and cost were lower in patients who underwent sedation than GA (171.39 ± 45.09 minutes vs 202.92 ± 43.85 and 8.00 ± 7.02 CNY vs 8.79 ± 11.63 CNY, respectively). CONCLUSION: GA is not superior to sedation, in terms of ablation time and freedom from atrial arrhythmia at 1 year, whereas patients with GA had more anesthesia time and procedure cost than sedation.

Suppressive effects of RASAL2 on renal cell carcinoma via SOX2/ERK/p38 MAPK pathway.

Metastatic renal cell carcinoma (RCC) is associated with poor prognosis. Ras protein activator like 2 (RASAL2) protein has been previously demonstrated to serves as a tumor suppressor in a variety of malignancies. Therefore, the aim of the present study was to investigate the role of RASAL2 in RCC. Reverse transcription-quantitative PCR, western blot analysis and immunohistochemistry were performed to measure mRNA and protein expression in RCC tissues, whilst immunofluorescence and western blotting were performed to evaluate protein expression in RCC cells. A Cell Counting Kit-8 and 5-bromo-2'-deoxyuridine staining were applied to determine cell viability, and Transwell assays were conducted to measure RCC cell invasion and migration. RASAL2 expression was identified to be downregulated in RCC tissues, which associate negatively with RCC pathological grade. Sox2 expression, in addition to ERK1/2 and p38 MAPK phosphorylation, were demonstrated to be increased in RCC tissues. In RCC cells, RASAL2 overexpression decreased the expression of Sox2 and the activation of ERK1/2 and p38 MAPK. Physiologically, RASAL2 overexpression decreased RCC cell viability, invasion and migration. The expression of metalloproteinase-2/9 and tissue inhibitor of metalloproteinase 1 were also identified to be decreased and increased by RASAL2 overexpression, respectively. By contrast, RASAL2 knockdown exerted opposite effects on RCC cells compared with those observed following RASAL2 overexpression. RASAL2 expression decreased RCC cell viability, migration and invasion, which was demonstrated to be associated with the inactivation of SOX2/ERK1/2/p38 MAPK signaling. These results suggest that RASAL2 may potentially serve as a potential target for the development of novel therapeutic intervention strategies against RCC.