The leakage of sewer systems and the impact on the 'black and odorous water bodies' and WWTPs in China.

China has achieved significant progress on wastewater treatment and aquatic environmental protection. However, leakage (in- and exfiltration) of sewer systems is still an issue. By using the statistical data of water and wastewater in 2016 in China, and the person loads (PLs) of water and wastewater in Singapore, the leakage fractions of hydraulic flow, organic carbon (COD), nitrogen (N) and phosphorus (P) mass loading, and in-sewer COD biological removal in the sewer systems of China (except Hong Kong, Macau and Taiwan), Shanghai, Guangzhou and Beijing were reported for the first time. The fractions of hydraulic flow infiltration (13%, Shanghai and Guangzhou) and exfiltration (39%, China) were calculated. Except Beijing, whose sewer networks are under appropriate management with small leakage fractions, the exfiltration fractions of COD (including in-sewer biological COD removal) ranged from 41% (Shanghai) to 66% (China) and averaged 55%; N ranged from 18% (Shanghai) to 48% (China) and averaged 33%; and P ranged from 23% (Shanghai and Guangzhou) to 44% (China) and averaged 30%. The exfiltrated sewage, COD, N and P not only wastes resources, but also contaminates the aquatic environment (especially groundwater) and contributes to 'black and odorous water bodies'. In- and exfiltration in the sewer network leads to low influent COD concentration, C/N ratio and high inorganic solids and inert particulate COD concentrations of many municipal wastewater treatment plants (WWTPs) causing high cost for nutrient removal, poor resource recovery, additional reactor/settler volume requirement and other operational problems. Therefore, tackling sewer leakage is of primary importance to today's environment in China. Recommendations for the inspection of sewer systems and the rehabilitation of damaged sewers as well as the development of design and operation guidelines of municipal WWTPs tailored to the specific local sewage characteristics and other conditions are proposed.

Discussion on Standardization of Forensic Assessment of Olfactory Dysfunction.

ABSTRACT: With the development of society, the improvement of living standards and the advancement of research methods, olfactory function has been paid more and more attention. Therefore, higher requirements for the forensic identification of olfactory function have also been put forward. Standardization construction of forensic medical examination and identification of olfactory dysfunction is urgently needed. Based on a comprehensive review of olfactory function and forensic assessment of olfactory dysfunction, this paper elaborates on problems related to the principles and timing of forensic assessment of olfactory dysfunction, the requirements of identification of traumatic olfactory dysfunction, the subjective and objective methods of examination of olfactory function. Strict control of the above issues is an important mean of standardization of forensic assessment of olfactory dysfunction.

Analysis on Forensic Expertise of 49 Medical Disputes in Prenatal Examination.

OBJECTIVES: To analyze the cases of medical disputes involving prenatal examination from a point of view of forensic expertise, and to discuss the risk of medical disputes and the preventive measures. METHODS: A retrospective analysis was conducted on 49 forensic expertise cases of medical disputes in prenatal examination which were identified in Academy of Forensic Science and Shanghai Di'an Forensic Science Limited Company from 2010 to 2017. RESULTS: In recent years, the number of medical disputes involving prenatal examination showed an increasing trend year by year. The common causes of medical disputes were: uninformed or insufficiently informed disclosure （20 cases）; the propaganda and application of three-dimensional, four-dimensional ultrasound were not standardized （14 cases）; ultrasound examination and serological screening process were not standardized （12 cases）; no antenatal counseling （2 cases）, etc. CONCLUSIONS: In order to minimize the occurrence of such medical disputes, hospitals or related associations should avoid the risk of prenatal examination through the standardization of management and operation.

Retrospective Analysis of 24 Cases of Forensic Medical Identification on Traumatic Tympanic Membrane Perforations.

OBJECTIVES: To study the case characteristics of forensic medical identification of traumatic tympanic membrane perforations, and to discuss the key points of forensic medical identification and evaluations methods for tympanic membrane perforations. METHODS: Twenty-four cases of traumatic tympanic membrane perforations accepted by the Academy of Forensic Science during 2017 were retrospectively analysed. The data of perforation size, form, predilection site, healing time and healing mode were evaluated. RESULTS: For the traumatic tympanic membrane perforations, the study showed that the small size of perforation （<1/2 quadrant） with irregular shape was common. The location of perforations was almost on the anterior and inferior quadrant, and centripetal migration healing was common. The healing rate within 6 weeks was up to 90%. CONCLUSIONS: In the identification cases of traumatic tympanic membrane perforations, the key is to determine whether it is traumatic and whether it will heal spontaneously within 6 weeks. It is suggested to check the tympanic membrane weekly by an otic endoscope combined with acoustic impedance measurement at the sixth week, which can improve the accuracy, objectivity and scientificity of the identification.

Seroepidemiology of Toxoplasma gondii infection in patients with liver disease in eastern China.

The role of the protozoan parasite Toxoplasma gondii in the pathogenesis of liver disease has recently gained much interest. The aim of this study was to determine the prevalence and risk factors associated with T. gondii infection in patients with liver disease from three cities in Shandong and Henan provinces, China. A case-control study was conducted from December 2014 to November 2015 and included 1142 patients with liver disease and 1142 healthy controls. Serum samples were collected from all individuals and were examined with enzyme-linked immunosorbent assay for the presence of anti-T. gondii IgG and IgM antibodies. Information on the demographics, clinical, and lifestyle characteristics of the participants was collected from the medical records and by the use of a questionnaire. The prevalence of anti-T. gondii IgG was 19·7% in patients with liver disease compared with 12·17% in the controls. Only 13 patients had anti-T. gondii IgM antibodies compared with 12 control individuals (1·14% vs. 1·05%, respectively). The highest seroprevalence was detected in patients with liver cancer (22·13%), followed by hepatitis patients (20·86%), liver cirrhosis patients (20·42%), and steatosis patients (20%). Multivariate logistic regression analysis indicated that consumption of raw meat (odds ratio (OR) = 1·32; 95% confidence interval (CI) 1·01-1·71; P = 0·03) and source of drinking water from wells (OR = 1·56; 95% CI 1·08-2·27; P = 0·01) were independent risk factors for T. gondii infection in liver disease patients. These findings indicate that T. gondii infection is more likely to be present in patients with liver disease. Therefore, efforts should be directed toward health education of populations at high risk of T. gondii infection and measures should be taken to protect vulnerable patients with liver disease.

Effect of 1,25(OH2D3 on the proliferation of human mesangial cells and their expression of Ki67.

Previous studies have found that 1,25-dihydroxyvitamin D3 [1,25(OH)2D3 or VD3] exerts many biological effects, including the inhibition of cell proliferation and induction of apoptosis, but its mechanism of action remains unclear. The goal of our investigation was to explore the effects of 1,25(OH)2D3 on the proliferation of cultured human mesangial cells and their expression of Ki67 in vitro, and to establish its mechanism of action. Cultured human mesangial cells were randomly divided into the following four groups: normal control (N group; administered Dulbecco's modified Eagle's medium containing 5% fetal bovine serum), proliferation [epidermal growth factor (EGF) group; administered 10 µg/L EGF], VD3 intervention [administered 10-8 M 1,25(OH)2D3], and proliferation and intervention [EGF+VD3 group; administered 10 µg/L EGF and 10-8 M 1,25(OH)2D3]. Cells were incubated for 48 h with the corresponding treatment, and fluorescence immunocytochemistry and reverse transcription-quantitative polymerase chain reaction were used to detect expression of Ki67 protein and mRNA, respectively. Compared to the N group, Ki67 levels were found to be higher in the EGF group but significantly lower in the VD3 intervention group. Moreover, expression of Ki67 by cells in the EGF+VD3 group was significantly lower than that of those in the EGF group. All of these differences were statistically significant (P < 0.05). In conclusion, 1,25(OH)2D3 inhibited Ki67 expression and the proliferation of human mesangial cells; therefore, Ki67 may be regarded as a potent therapeutic target in mesangial proliferative glomerulonephritis.

[Clinical application of hybrid surgery for the treatment of cerebral arteriovenous malformations].

Objective: To investigate the application of hybrid technique for the treatment of cerebral arteriovenous malformations (CAVMs) and to assess the value of hybrid technique. Methods: The cases of CAVMs treated in Qilu hospital and People's Hospital of Xinjiang Uygur Autonomous Region from July 2011 to July 2016 were analyzed retrospectively.Two modes of hybrid surgery, "angiographic diagnosis-craniotomy lesion resection or/and hematoma clearance-intraoperative angiography evaluation" and "angiographic diagnosis-intraoperative embolization-craniotomy lesion resection or/and hematoma clearance-intraoperative angiography evaluation" were applied for all the cases.We placed an aneurysm clip as marker in surgery field during real-time angiography.If CAVMs residues occurred during surgery, we re-resected the residue according to the guidance of the marker (clip) and DSA imaging. Intra-operative angiography evaluated the results of CAVMs resection one more time.Postoperatively, follow-up CT scan was performed for all the patients. Results: Of all the cases with CAVMs, there were 8 cases of scale Ⅰ, 13 cases of scale Ⅱ, 10 cases of scale Ⅲ and 6 cases of scale Ⅳ according to Spetzler-Martin Scale.There were 28 cases of acute hemorrhagic CAVMs and 9 cases of chronic hemorrhagic CAVMs or no-hemorrhagic CAVMs.Intra-operative angiography showed CAVMs residues in 6 cases of acute hemorrhagic CAVMs and only one in chronic group.About 18.92% residual rate of CAVMs were found for the first time intra-operative assessment angiography.With the guidance of intra-operative angiography and aneurysm clip as Marker, all residues of CAVMs were resected totally.Follow up CT showed the hematomas disappeared in all the cases of acute hemorrhagic cases.The cure rate of CAVMs with hybrid surgery was 100% according to the final intra-operative assessment angiography. Conclusions: (1)Hybrid surgery for the treatment of CAVMs in one session could evaluate the results of CAVMs resection and instruct the surgical procedure according to real-time angiography.This model could improve the treatment safety and efficacy for patients with CAVMs.(2)Patients with higher Spetzler-Martin Scale (Ⅲ-Ⅳ) who need intra-operative embolization and patients with hemorrhagic CAVMs are more suitable for hybrid surgery.

Research on Auditory Long Latency Response in Normal Hearing Subjects.

OBJECTIVES: To explore the characters and the relationship among latency response, amplitude and sound stimulus intensity of auditory long latency response（ALR）, and to investigate the significance of ALR applied in auditory threshold prediction. METHODS: Total 46 subjects （92 ears） with normal hearing were tested by ALR. The ALR waves of the subjects were elicited by 5 sound stimulus intensity according to the order of 70, 50, 30, 20 and 10 dB nHL. By making N1 wave and P2 wave, the values of 3 observed indexes （the latencies of N1 wave and P2 wave and N1-P2 amplitude） were obtained, and the variation trend of the observed indexes were statistically analyzed. The differences in the frequency of the indexes were observed. RESULTS: The rate of ALR waves from 46 subjects （92 ears） with normal hearing was 100%. The latencies of N1 wave and P2 wave delayed gradually and N1-P2 amplitude declined with sound stimulus intensity descending. CONCLUSIONS: In suitable conditions, ALR is a stable technology for hearing thresholds prediction. The relation between sound stimulus intensity and latency of N1 wave, latency of P2 wave and N1-P2 amplitude of ALR plays an important part in auditory thresholds assessment.

Expression of macrophage migration-inhibitory factor in duodenal ulcer and its relation to Helicobacter pylori infection.

The aim of this study was to examine the expression of macrophage migration-inhibitory factor (MIF) in duodenal ulcer epithelial cells and its relation to Helicobacter pylori (Hp) infection, and to discuss the pathogenic roles of MIF expression and Hp infection in duodenal ulcer. MIF protein and mRNA expression was examined in samples from patients with duodenal ulcer with and without Hp infection (N = 40 each, experimental group), and in normal duodenal bulb mucosal tissue (N = 40, control group) using immunohistochemistry and in situ hybridization. Patients without Hp infection received routine treatment, and treatment was provided to the patients positive for Hp to eradicate Hp infection. Hp and MIF expression levels before treatment and after the ulcer had been cured were compared. The positive rates of MIF protein and mRNA in patients with Hp infection before treatment were 67.5 and 65%, respectively, and were 18.9 and 21.6% in the 37 patients from whom Hp was eliminated. These were statistically different both before and after treatment compared with controls (P < 0.05). In the patients without Hp infection, the positive rates of MIF protein and mRNA expression before (45 and 47.5%, respectively) and after (32.5 and 30%) treatment were not significantly different (P > 0.05). The results of this study suggested that MIF is related to the development of duodenal ulcer, and that the presence of Hp is closely related with the expression of MIF in the duodenal mucosa and the development of duodenal ulcer.

Synonymous codon selection in the hepatitis B virus translation initiation region.

Hepatitis B virus (HBV) infection is a major health problem worldwide. This virus and its hosts are often fated to continual co-evolutionary interactions. Codon usage analysis has significance for studies of co-evolution between viruses, their hosts, and mRNA translation. Adaptation of the overall codon usage pattern of HBV to that of humans is estimated using the synonymous codon usage value (RSCU), and the synonymous codon usage biases for the translation initiation region (TIR) of HBV are analyzed by calculation of the usage fluctuation of each synonymous codon along the TIR (the first 50 codon sites of the whole coding sequence of HBV). With respect to synonymous codon usage, our results demonstrated that HBV had no significant tendency to select over-represented codons, but had a significant tendency to select certain under-represented codons in the viral genome. Within the three common HBV hosts, 14 of 59 codons had a similar usage pattern, suggesting that mutation pressure from this DNA virus played an important role in the formation of virus synonymous codon usage. In addition, there was no obvious trend for the codons with relatively low energy to be highly selected in the TIR of HBV, suggesting that the synonymous codon usage patterns for the TIR might not be affected by the nucleotide sequence secondary structure; however, synonymous codon usage in the TIR of HBV was influenced by the overall codon usage patterns of the hosts to some degree. Our results suggest that mutation pressure from HBV plays an important role in the formation of synonymous codon usage of the viral genome, while translation selection from the hosts contributes to virus translational fine-tuning.

Control of postharvest grey mould decay of nectarine by tea polyphenol combined with tea saponin.

UNLABELLED: The control efficacy of tea polyphenol (TP) in combination with tea saponin (TS) against nectarine grey mould decay caused by Botrytis cinerea and the underlying mechanism were investigated. The in vitro experiments showed that both TP and TS inhibited the mycelial growth in a dose-dependent manner, and their combinations exhibited synergistic antifungal interactions with the synergistic ratios (SR) exceeding 1·5. The in vivo experiments showed that disease incidence and lesion diameter of grey mould of inoculated fruit were significantly lowered after being treated with the combination of TP and TS; furthermore, the activities of phenylalanine ammonia-lyase (PAL), peroxidase (POD), polyphenol oxidase (PPO), chitinase and ß-1,3-glucanase of inoculated fruit as well as the contents of total phenolic and lignin were significantly induced, the respiration rate of inoculated fruit was significantly decreased and therefore the quality decrease was accordingly retarded. These results revealed that TP in combination with TS could control grey mould of inoculated nectarines and their mechanism of action might be attributed to their active components, the induction of defensive system and the regulation of respiration. SIGNIFICANCE AND IMPACT OF THE STUDY: This study demonstrates that the combination of TP and TS has exhibited synergistic antifungal interactions against Botrytis cinerea, and it suggests that their combination may be useful and effective agents for the control of nectarine grey mould decay. Such natural products therefore represent a promising alternative to synthetic fungicides in the control of nectarine postharvest diseases.

Ultrasonic bone curette in thoracic spinal decompression: a comprehensive systematic review and meta-analysis.

OBJECTIVE: The aim of this study was to compare the efficacy and safety of ultrasonic bone curette (UBC) and conventional surgical instruments in thoracic laminectomy decompression (TLD) for the treatment of thoracic spinal stenosis (TSS) by meta-analysis. MATERIALS AND METHODS: Two authors independently searched Medline via PubMed, Embase, Cochrane Library, Web of Science, Wanfang Database, and China National Knowledge Infrastructure for the period from the establishment of the database until January 2023 to identify the studies on the safety and efficacy of UBC vs. conventional instruments for TSS. Data extraction and quality assessment were performed by two researchers independently. We used RevMan 5.4 software (Review Manager Web, The Cochrane Collaboration, Copenhagen, Denmark) to analyze the data. RESULTS: Eight retrospective studies were included in the present work. This meta-analysis revealed that no significant differences in the preoperative JOA scores, the JOA scores at the last follow-up, the improvement rate of JOA scores, and the incidence of cerebrospinal fluid leakage/dura injury were detected between the two groups (p>0.05). However, there were significant differences in the operative time and intraoperative blood loss during single-level TLD [operative time: MD=-1.47, 95% CI (-1.86, -1.09), p<0.001; intraoperative blood loss: MD=-46.62, 95% CI (-53.83, -39.40), p<0.001], total operative time [MD=-56.88, 95% CI (-69.66, -44.10), p<0.001], total intraoperative blood loss [MD=-143.52, 95% CI (-212.49, -74.54), p<0.001], the incidence of neurological deterioration/nerve root injury [RR= 0.29, 95% CI (0.09, 0.91), p=0.03] between the groups. CONCLUSIONS: The application of UBC in TLD to treat TSS is safe and effective. UBC can significantly shorten operation time and reduce intraoperative blood loss compared to traditional surgical instruments. Moreover, it has the advantage of reducing perioperative nerve injury.

[Analysis of upper airway morphology and laryngopharyngeal reflux in obese patients with OSA].

Objective: To investigate the morphological characteristics of upper airway and laryngopharyngeal reflux in obese patients with obstructive sleep apnea (OSA). Methods: A retrospective analysis was performed on the clinical data of 284 adult patients who underwent polysomnography (PSG) from April 2020 to April 2021 in the Department of Otorhinolaryngology, Head and Neck Surgery, Zhongnan Hospital of Wuhan University, including 83 males and 201 females, aged (32.70±7.74) years. Patients were divided into obese group (n=234) and non-obese group (n=50) according to body mass index (BMI). Patients were divided into mild OSA group, moderate OSA group, severe OSA group and extremely severe OSA group by PSG.The results of sleepiness and laryngopharyngeal reflux questionnaire, nasolaryngoscopy and polysomnography were compared in each group. SPSS (version 22.0) software was used in data analysis. Results: Compared with the non-obese OSA group, the lymphoid hyperplasia of tongue root was more heavy in the obese OSA group, and Mueller's maneuver showed that the left-right lateral collapse of the velopharyngeal plane was more serious. Meanwhile, the scores of reflux symtom index (RSI) and reflux finding score (RFS) in the obese OSA group were significantly increased, and the scores of RSI and RFS increased with the increase of OSA severity. The main respiratory events in obese patients with OSA were obstructive hypopnea, their apnea-hypopnea indices(AHI) during REM (AHIREM) was significantly higher than non-REM (AHINREM), and they had lower average blood oxygen saturation. Yet, there was no significant difference in the lowest blood oxygen saturation between the two groups. Conclusions: Our study suggests that lateral pharyngeal wall stenosis in velopharyngeal plane and the lymphoid hyperplasia of tongue root in glossopharyngeal plane occurs more frequently in obese patients with OSA. Laryngopharyngeal reflux is significantly increased in obese patients, and OSA increases laryngopharyngeal reflux in obese patients.

[Efficacy and safety of endoscopic retrograde cholangiopancreatography in children].

Objective: To investigate the efficacy and safety of endoscopic retrograde cholangiopancreatography (ERCP) in the diagnosis and treatment of biliary and pancreatic diseases in children. Methods: The clinical data of 127 children who were treated with ERCP in the First Affiliated Hospital of Nanchang University from January 2007 to July 2021 were analyzed. According to the diseases they suffered from, the children were divided into biliary group and pancreatic group. The operation times, technical success rate, diagnosis, interventions and post-ERCP complications between the groups were compared by t-test or χ2 test. The risk factors of post-ERCP pancreatitis (PEP) were analyzed by multivariate Logistic regression. Results: A total of 127 children, including 54 males and 73 females, with a median age of 14 years at first ERCP, were included in this study. ERCP was performed in 181 cases, with a success rate of 98.3% (178/181). In pre-ERCP imaging examination, the positive diagnostic rates of ultrasound, CT and magnetic resonance cholangiopancreatography (MRCP) for biliary and pancreatic diseases were 54.1% (53/98), 56.1% (37/66) and 79.3% (88/111), respectively. MRCP had the highest positive diagnostic rate, and the difference among the three measures was statistically significant (χ2=17.33, P<0.001). The most common indications for ERCP in biliary and pancreatic diseases were choledocholithiasis (77.0%, 107/139) and congenital structural abnormalities of the pancreas (31.0%, 13/42), respectively. After ERCP, the abdominal pain was dramatically relieved and the liver function was significantly improved (all P<0.001). The blood amylase level of the children with pancreatic diseases was significantly lower than that before ERCP (t=7.73, P<0.001). The overall incidence of post-ERCP complications was 12.2% (22/181), of which post-ERCP pancreatitis (PEP) was the most common (7.2%, 13/181). The incidence of PEP was significantly higher in the pancreatic group than in the biliary group (16.7% (7/42) vs. 4.3% (6/139),χ2=7.38, P=0.007). Multivariate Logistic regression analysis showed that young age was the independent risk factor of PEP (OR=0.80, 95%CI 0.67-0.96). Conclusions: MRCP is the first choice for pre-ERCP imaging examination of biliary and pancreatic diseases in children. ERCP can be safely and effectively used in the diagnosis and treatment of biliary and pancreatic diseases in children, with a high success rate and obvious alleviation of symptoms.

cAMP/PKA/CREB signaling pathway-mediated effects of melatonin receptor genes on clock gene expression in Bactrian camel ovarian granulosa cells.

The cAMP/PKA/CREB pathway is involved in the regulation of melatonin during important physiological activities in mammals. However, the regulation of circadian clock genes in ovarian granulosa cells remains unclear. Herein, we determined the relationship between melatonin and biological clock genes using cultured Bactrian camel ovarian granulosa cells. The enzyme-linked immunosorbent assays showed that the cAMP content was reduced when melatonin receptor (MT) genes or cryptochrome (Cry) genes were overexpressed; the quantitative polymerase chain reaction and western blot analyses revealed that the expression levels of all circadian clock genes (GNB2, PKA, CREB, Per1/2/3, and Clock) except Cry1/2 decreased significantly at 24 h. Cellular immunolocalization analysis showed that melatonin receptors were localized in the cell membrane and cytoplasm; the CRY protein was mainly localized in the nucleus. Overall, our findings indicated that the rhythmic regulation of ovarian granulosa cells was consistent with the regulatory action of the central circadian clock.

Association study of SNCA gene polymorphisms with schizophrenia in a Chinese North Han population.

OBJECTIVE: Previous studies suggested that the alpha-synapse protein (SNCA) gene and its coding product α-synuclein (α-Syn) may play a role in the pathogenesis of neurodegenerative diseases. The mutation of SNCA can influence the formation of nerve fibers and the function of dopaminergic neurons, and that may be related to addictive behavior, such as alcohol dependence. SNCA may overlap with the pathogenesis of schizophrenia and Parkinson's disease or alcohol dependence associated with the dopamine pathway. The aim was to determine the association between three SNCA SNPs (rs3822086C/T, rs11931074G/T, and rs356219A/G) and schizophrenia in a Chinese North Han population. PATIENTS AND METHODS: A total of 878 subjects, with or without schizophrenia, were included in our study. DNA purification, Polymerase Chain Reaction (PCR) amplification, and subsequent restriction fragment length polymorphism (RFLP) analysis were manipulated to determine genotypes. RESULTS: Between the schizophrenia group and healthy group, neither the genotype nor allele frequencies of rs3822086C/T, rs11931074G/T, or rs356219A/G differed significantly in either the total sample or the subgroups. In the haplotype analysis, the ATT and GTT haplotype frequencies differed significantly between the patients and controls in the total sample (χ2=6.052, p=0.0139; χ2=4.508, p=0.0337). In the female subgroup, the ATT haplotype frequency differed significantly between the patients and controls (χ2=4.219, p=0.04). CONCLUSIONS: There was no association between SNCA polymorphisms and schizophrenia in the North Han Chinese population, and the ATT haplotype may be a susceptibility factor for schizophrenia.

EHMT2 promotes the development of prostate cancer by inhibiting PI3K/AKT/mTOR pathway.

OBJECTIVE: To investigate the expression characteristics and the potential role of euchromatic histone-lysine N-methyltransferase 2 (EHMT2) in the clinical pathology and prognosis of prostate cancer (PCa). PATIENTS AND METHODS: Quantitative Real-time polymerase chain reaction (qRT-PCR) was performed to detect the expression of EHMT2 in 55 pairs of PCa tissues and adjacent normal tissues. The relationship between EHMT2 expression and the pathological features, as well as the prognosis of PCa patients was analyzed. EHMT2 expression in PCa cells was determined by qRT-PCR as well. In addition, EHMT2 knockdown model was constructed by transfection of the small interfering RNA in PCa cell lines PC-3 and DU-145. The regulatory effects of EHMT2 on the behaviors of PCa cells were evaluated through cell counting kit-8 (CCK-8), 5-Ethynyl-2'-deoxyuridine (EdU), colony formation assay and flow cytometry. Finally, we detected the protein levels of relative genes in PI3K/AKT/mTOR pathway through Western blot. RESULTS: QRT-PCR results showed that the expression level of EHMT2 in PCa tissues was markedly higher than that in adjacent normal tissues. Compared with PCa patients with low expression of EHMT2, those with high expression of EHMT2 had higher pathological grade and lower overall survival. EHMT2 was also highly expressed in PCa cell lines. Knockdown of EHMT2 inhibited the proliferative potential and induced apoptosis of PCa cells. Western blot results revealed that PCa cells with EHMT2 knockdown presented downregulated p-PI3K, p-AKT and p-mTOR. CONCLUSIONS: EHMT2 was highly expressed in PCa, and its expression is closely correlated with tumor stage and poor prognosis of PCa patients. EHMT2 promoted the malignant progression of PCa by inhibiting PI3K/AKT/mTOR pathway.