Knocking down AR promotes osteoblasts to recruit prostate cancer cells by altering exosomal circ-DHPS/miR-214-3p/CCL5 pathway.

ABSTRACT: Tumor-derived exosomes have been shown to play a key role in organ-specific metastasis, and the androgen receptor regulates prostate cancer (PCa) progression. It is unclear whether the androgen receptor regulates the recruitment of prostate cancer cells to the bone microenvironment, even bone metastases, through exosomes. Here, we found that exosomes isolated from PCa cells after knocking down androgen receptor (AR) or enzalutamide treatment can facilitate the migration of prostate cancer cells to osteoblasts. In addition, AR silencing or treatment with the AR antagonist enzalutamide may increase the expression of circular RNA-deoxyhypusine synthase (circ-DHPS) in PCa cells, which can be transported to osteoblasts by exosomes. Circ-DHPS acts as a competitive endogenous RNA (ceRNA) against endogenous miR-214-3p to promote C-C chemokine ligand 5 (CCL5) levels in osteoblasts. Increasing the level of CCL5 in osteoblasts could recruit more PCa cells into the bone microenvironment. Thus, blocking the circ-DHPS/miR-214-3p/CCL5 signal may decrease exosome-mediated migration of prostate cancer cells to osteoblasts.

[Effects of chitosan oligosaccharide on bone metabolism and IKK/NF-κB pathway in rats with osteoporosis and periodontitis].

PURPOSE: To investigate the effects of chitosan oligosaccharide on bone metabolism and IKK/NF-κB pathway in mice with osteoporosis and periodontitis. METHODS: Thirty rats were randomly divided into 3 groups, with 10 rats in each group. They were divided into control group, ovariectomized periodontitis group and chitosan oligosaccharide treatment group. Except for the control group, the other two groups were ovariectomized and smeared with Porphyromonas gingivalis fluid to establish the model of osteoporosis with periodontitis. Four weeks after ligation, the rats in chitosan oligosaccharide treatment group were gavaged with 200 mg/kg chitosan oligosaccharide, and the other two groups were gavaged with equal volume of normal saline once a day for 90 days. The periodontal tissues of each group were observed before administration, and the bone mineral density of rats was detected by dual energy X-ray animal bone mineral density and body composition analysis system. After 90 days of administration, the bone mineral density was detected again. After administration, blood was collected from tail vein, and the contents of serum alkaline phosphatase (ALP), bone Gla protein (BGP) and tartrate resistant acid phosphatase 5b (TRACP5b) were measured by enzyme-linked immunodeficient assay. The gingival index and periodontal attachment loss of rats in each group were obtained by visual examination and exploratory examination. The maxilla was removed, and the distance from the enamel cementum boundary to the alveolar crest was measured to obtain alveolar bone absorption value. H-E staining was used to observe the pathology of maxilla in each group. RT-PCR and Western blot were used to detect the nuclear factors in periodontal tissue of rats in each group. SPSS 22.0 software package was used for statistical analysis. RESULTS: Before administration, the gums of the control group were pink without bleeding, and the gums of the other two groups were red and swollen with slight bleeding. After administration, compared with the control group, the bone mineral density, serum ALP, BGP of ovariectomized periodontitis group decreased significantly(P＜0.05); while TRACP5b, gingival index, loss of periodontal attachment and alveolar bone resorption, NF-κB and IKK mRNA and protein expression in periodontal tissue increased significantly(P＜0.05). Compared with the ovariectomized periodontitis group, the bone mineral density, serum ALP, BGP were significantly increased(P＜0.05); while TRACP5b, gingival index, periodontal attachment loss and alveolar bone resorption, NF-κB and IKK mRNA and protein expression in periodontal tissue were significantly decreased (P＜0.05). In the ovariectomized periodontitis group, the periodontal tissue combined with epithelium was separated from the tooth surface, the dental pocket was obvious and deep, and the height of alveolar bone decreased. Although dental pocket could be observed in the periodontal tissue of rats treated with chitosan oligosaccharide, it was not obvious, and new bone appeared around the alveolar bone. CONCLUSIONS: Chitosan oligosaccharide can induce biochemical indexes of bone metabolism to become normal, alleviate the symptoms of periodontitis, this may be related to the inhibition of IKK/NF-κB pathway by chitosan oligosaccharide.

Analysis of factors influencing campus bullying among junior and senior school students and construction of a nomogram model from Jiangsu Province / 中国学校卫生

Objective@#To explore the influencing factors of exposure to campus bullying among junior and senior school students, and to establish a column line diagram model for risk prediction, while providing a theoretical basis for campus bullying prevention and control in secondary schools.@*Methods@#A total of 22 034 junior and senior school students were selected via direct sampling technique from September to November 2021 in 13 cities in Jiangsu Province, China, and questionnaires were administered using the Student Health Behavior Questionnaire. The Chi squared test and multifactor Logistic regression analysis were used to derive the influencing factors of exposure to campus bullying, and a column line graph prediction model was drawn.@*Results@#A total of 540 students reported that they had experienced campus bullying, with a prevalence rate of 2.45%. Being in a non conventional family ( OR =1.30,95% CI =1.02-1.65), overweight/obesity ( OR =1.35,95% CI =1.09-1.67), scolding by parents in the past 30 days ( OR =2.27,95% CI =1.82-2.84), cigarette smoking in the past 30 days ( OR =1.54,95% CI =1.11-2.15), Internet addiction ( OR =2.03，95% CI =1.34-3.08), and depressive symptoms( OR =5.24，95% CI =4.16-6.61), all of which were positively correlated with exposure to campus bullying among junior and senior school students ( P <0.05). Furthermore, the following factors were negatively associated with junior and senior school students protection from campus bullying in female students ( OR = 0.58 , 95% CI =0.46-0.72)，senior school students ( OR =0.68，95% CI =0.54-0.83), eating breakfast sometimes ( OR =0.37，95% CI = 0.22 -0.62), and eating breakfast everyday ( OR =0.28，95% CI =0.17-0.49) ( P <0.05). The column line graph established based on the above influencing factors had an area under the curve of 0.792 (95% CI =0.769-0.815), and the calibration curve showed that the predicted value was basically the same as the measured value.@*Conclusions@#Non conventional families, overweight/obesity, male students, junior school students, scolding by parents, cigarette smoking, Internet addiction, and depressive symptoms are correlated with school bullying among middle school students. The predictive model constructed in the study can provide an effective basis to predict the risk of school bullying and facilitate the implementation of proactive interventions for junior and senior school students.

Protectin conjugates in tissue regeneration 1 restores lipopolysaccharide-induced pulmonary endothelial glycocalyx loss via ALX/SIRT1/NF-kappa B axis.

BACKGROUND: Endothelial glycocalyx loss is integral to increased pulmonary vascular permeability in sepsis-related acute lung injury. Protectin conjugates in tissue regeneration 1 (PCTR1) is a novel macrophage-derived lipid mediator exhibiting potential anti-inflammatory and pro-resolving benefits. METHODS: PCTR1 was administrated intraperitoneally with 100 ng/mouse after lipopolysaccharide (LPS) challenged. Survival rate and lung function were used to evaluate the protective effects of PCTR1. Lung inflammation response was observed by morphology and inflammatory cytokines level. Endothelial glycocalyx and its related key enzymes were measured by immunofluorescence, ELISA, and Western blot. Afterward, related-pathways inhibitors were used to identify the mechanism of endothelial glycocalyx response to PCTR1 in mice and human umbilical vein endothelial cells (HUVECs) after LPS administration. RESULTS: In vivo, we show that PCTR1 protects mice against lipopolysaccharide (LPS)-induced sepsis, as shown by enhanced the survival and pulmonary function, decreased the inflammatory response in lungs and peripheral levels of inflammatory cytokines such as tumor necrosis factor-α, interleukin-6, and interleukin-1ß. Moreover, PCTR1 restored lung vascular glycocalyx and reduced serum heparin sulphate (HS), syndecan-1 (SDC-1), and hyaluronic acid (HA) levels. Furthermore, we found that PCTR1 downregulated heparanase (HPA) expression to inhibit glycocalyx degradation and upregulated exostosin-1 (EXT-1) protein expression to promote glycocalyx reconstitution. Besides, we observed that BAY11-7082 blocked glycocalyx loss induced by LPS in vivo and in vitro, and BOC-2 (ALX antagonist) or EX527 (SIRT1 inhibitor) abolished the restoration of HS in response to PCTR1. CONCLUSION: PCTR1 protects endothelial glycocalyx via ALX receptor by regulating SIRT1/NF-κB pathway, suggesting PCTR1 may be a significant therapeutic target for sepsis-related acute lung injury.

Nontuberculous mycobacteria in China: incidence and antimicrobial resistance spectrum from a nationwide survey.

BACKGROUND: Information on the prevalence and resistance spectrum of nontuberculous mycobacteria (NTM) in China is mainly based on regional or local data. To estimate the proportion of NTM cases in China, a national survey of NTM pulmonary disease was carried out based on acid-fast positive sputum samples collected in 2013. METHODS: Sputum samples collected from enrolled presumptive cases in 72 nationwide tuberculosis surveillance sites from the 31 provinces in the mainland of China were cultured using L-J medium at the National tuberculosis reference laboratory (NTRL). MALDI-TOF MS identified the species of re-cultured strains, and minimal inhibitory concentrations (MICs) were determined to evaluate the drug susceptibility of NTM isolates. Data analysis used statistical software SPSS version 22.0 for Windows statistical package. RESULTS: Of 4917 mycobacterial isolates cultured, 6.4% [317/4917, 95% confidence interval (CI) 5.8%-7.2%] were confirmed as NTM, among which 7.7% (287/3709, 95% CI 6.9%-8.6%) were from the southern region. In inland and coastal China, 87.7% (95% CI 78.7%-93.2%) and 50.0% (95% CI 43.7%-56.3%) of isolates, respectively, were slow-growing mycobacteria (SGM), with the remaining rapid growing mycobacteria (RGM). A total of 29 species were detected, Mycobacterium abscessus had higher clarithromycin-inducible resistance rates than M. massiliense (65.67% vs 2.22%). M. kansasii presented lower resistance rates in linezolid and moxifloxacin than M. avium-intracellulare complex (3.23% vs 66.67%, 0 vs 47.22%) and other SGM (3.23% vs 38%, 0 vs 26%). CONCLUSIONS: More NTM pulmonary disease was observed in the south and coastal China (P < 0.01). SGM was widely distributed, and more RGM are present in southern and coastal China (P < 0.01). The antimicrobial resistance spectrum of different NTM species was significantly different and accurate species identification would be facilitated to NTM pulmonary disease treatment.

PCTR1 ameliorates lipopolysaccharide-induced acute inflammation and multiple organ damage via regulation of linoleic acid metabolism by promoting FADS1/FASDS2/ELOV2 expression and reducing PLA2 expression.

Gram-negative bacterial infection causes an excessive inflammatory response and acute organ damage or dysfunction due to its outer membrane component, lipopolysaccharide (LPS). Protectin conjugates in tissue regeneration 1 (PCTR1), an endogenous lipid mediator, exerts fundamental anti-inflammation and pro-resolution during infection. In the present study, we examined the properties of PCTR1 on the systemic inflammatory response, organic morphological damage and dysfunction, and serum metabolic biomarkers in an LPS-induced acute inflammatory mouse model. The results show that PCTR1 reduced serum inflammatory factors and ameliorated morphological damage and dysfunction of the lung, liver, kidney, and ultimately improved the survival rate of LPS-induced acute inflammation in mice. In addition, metabolomics analysis and high performance liquid chromatography-mass spectrometry revealed that LPS-stimulated serum linoleic acid (LA), arachidonic acid (AA), and prostaglandin E2 (PGE2) levels were significantly altered by PCTR1. Moreover, PCTR1 upregulated LPS-inhibited fatty acid desaturase 1 (FADS1), fatty acid desaturase 2 (FADS2), and elongase of very long chain fatty acids 2 (ELOVL2) expression, and downregulated LPS-stimulated phospholipase A2 (PLA2) expression to increase the intrahepatic content of AA. However, these effects of PCTR1 were partially abrogated by a lipoxin A4 receptor (ALX) antagonist (BOC-2). In summary, via the activation of ALX, PCTR1 promotes the conversion of LA to AA through upregulation of FADS1, FADS2, and ELOVL2 expression, and inhibits the conversion of bound AA into free AA through downregulation of PLA2 expression to decrease the serum AA and PGE2 levels.

Maresin Conjugates in Tissue Regeneration 1 improves alveolar fluid clearance by up-regulating alveolar ENaC, Na, K-ATPase in lipopolysaccharide-induced acute lung injury.

Maresin Conjugates in Tissue Regeneration 1 (MCTR1) is a newly identified macrophage-derived sulfido-conjugated mediator that stimulates the resolution of inflammation. This study assessed the role of MCTR1 in alveolar fluid clearance (AFC) in a rat model of acute lung injury (ALI) induced by lipopolysaccharide (LPS). Rats were intravenously injected with MCTR1 at a dose of 200 ng/rat, 8 hours after administration of 14 mg/kg LPS. The level of AFC was then determined in live rats. Primary rat ATII (Alveolar Type II) epithelial cells were also treated with MCTR1 (100 nmol/L) in a culture medium containing LPS for 8 hours. MCTR1 treatment improved AFC (18.85 ± 2.07 vs 10.11 ± 1.08, P < .0001) and ameliorated ALI in rats. MCTR1 also significantly promoted AFC by up-regulating epithelial sodium channel (ENaC) and Na+ -K+ -adenosine triphosphatase (Na, K-ATPase) expressions in vivo. MCTR1 also activated Na, K-ATPase and elevated phosphorylated-Akt (P-Akt) by up-regulating the expression of phosphorylated Nedd4-2 (P-Nedd4-2) in vivo and in vitro. However, BOC-2 (ALX inhibitor), KH7 (cAMP inhibitor) and LY294002 (PI3K inhibitor) abrogated the improved AFC induced by MCTR1. Based on the findings of this study, MCTR1 may be a novel therapeutic approach to improve reabsorption of pulmonary oedema during ALI/acute respiratory distress syndrome (ARDS).

MCTR1 alleviates lipopolysaccharide-induced acute lung injury by protecting lung endothelial glycocalyx.

Endothelial glycocalyx degradation, critical for increased pulmonary vascular permeability, is thought to facilitate the development of sepsis into the multiple organ failure. Maresin conjugates in tissue regeneration 1 (MCTR1), a macrophage-derived lipid mediator, which exhibits potentially beneficial effects via the regulation of bacterial phagocytosis, promotion of inflammation resolution, and regeneration of tissue. In this study, we show that MCTR1 (100 ng/mouse) enhances the survival of mice with lipopolysaccharide (LPS)-induced (15 mg/kg) sepsis. MCTR1 alleviates LPS (10 mg/kg)-induced lung dysfunction and lung tissue inflammatory response by decreasing inflammatory cytokines (tumor necrosis factor-α, interleukin-1ß [IL-1ß], and IL-6) expression in serum and reducing the serum levels of heparan sulfate (HS) and syndecan-1. In human umbilical vein endothelial cells (HUVECs) experiments, MCTR1 (100 nM) was added to the culture medium with LPS for 6 hr. MCTR1 treatment markedly inhibited HS degradation by downregulating heparanase (HPA) protein expression in vivo and in vitro. Further analyses indicated that MCTR1 upregulates sirtuin 1 (SIRT1) expression and decreases NF-κB p65 phosphorylation. In the presence of BOC-2 or EX527, the above effects of MCTR1 were abolished. These results suggest that MCTR1 protects against LPS-induced sepsis in mice by attenuating pulmonary endothelial glycocalyx injury via the ALX/SIRT1/NF-κB/HPA pathway.

The diagnostic effect of serum miR-139-5p as an indicator in osteosarcoma.

BACKGROUND: The microRNA, miR-139-5p, plays an important role in the initiation and progression of various tumor types including osteosarcoma (OS). OBJECTIVE: This study aimed to detect the serum miR-139-5p expression in OS and analyze its association with clinical variables. METHODS: Blood samples were taken from 98 OS patients and 50 healthy individuals, and serum miR-139-5p levels were measured by quantitative reverse transcription-polymerase chain reaction. RESULTS: We found the expression of serum miR-139-5p in OS patients was significantly lower than that in healthy individuals, and miR-139-5p levels were dramatically decreased in patients with distant metastasis or in higher clinical stage. Receiver-operating characteristic (ROC) analysis revealed that serum miR-139-5p could well discriminate OS patients from healthy controls with a high sensitivity and specificity. Moreover, low serum miR-139-5p expression was strongly associated with distant metastasis, tumor stage and shorter overall survival. Both univariate and multivariate analyses showed that serum miR-139-5p level could serve as an independent prognostic marker for OS. CONCLUSIONS: Taken together, data from this study demonstrates that serum miR-139-5p could be used as a tumor biomarker for OS diagnosis and prognosis.

[Expressions of survivin, PI3K and AKT in keratinocytes in skin lesions and their pathogenic role in psoriasis vulgaris].

OBJECTIVE: To explore the role of survivin and PI3K/AKT pathway in the pathogenesis of psoriasis vulgaris (PV). METHODS: Plaque-like lesions collected from 22 patients with PV in progressive stage and 18 normal control skin specimens were examined using immunohistochemical staining, Western blotting and real-time quantitative PCR for expressions of survivin, PI3K and AKT in the keratinocytes, and their correlation was analyzed. A small interfering RNA (siRNA) was used to knock down AKT in cultured HaCaT cells, and Western blotting was used to detect the changes in the expression of survivin. RESULTS Compared with normal skin, PV lesions showed obviously up-regulated expressions of survivin, PI3K and AKT in the keratinocytes. Survivin expression was positively correlated with PI3K (r=0.4510, P=0.0351) and AKT (r=0.4423, P=0.0393) in the keratinocytes in PV lesions. In cultured HaCaT cells, siRNA-mediated knockdown of AKT caused down-regulation of survivin expression. CONCLUSION: Survivin and PI3K/AKT signaling pathway may participate in the occurrence and progression of PV.

[Regulatory effect of Skp2 on the expression and transactivation of the androgen receptor in the progression of castration-resistant prostate cancer].

OBJECTIVE: To determine the expression of Skp2 in different prostate cancer (PCa) cell lines and tissues, and explore its influence on the androgen receptor (AR) signaling pathway and development of castration-resistant prostate cancer (CRPC). METHODS: The expression levels of Skp2 and AR in different PCa cell lines were detected by Western blot. After knockdown of Skp2 in the C4-2 and 22RV1 cells transfected with shRNA, the expressions of AR and P27 were determined and the activity of ARR3-Luc measured by dual-luciferase reporter gene assay following treatment with dihydrotestosterone (DHT). The expressions of AR and Skp2 in human naïve PCa or CRPC specimens were detected by immunohistochemical staining followed by analysis of their differences and correlation. RESULTS: The Skp2 protein expression level was significantly higher in the C4-2 or 22RV1 cells than in the LNCaP cells. DHT treatment increased the expression of Skp2 in the C4-2 cells, but knock-down of Skp2 significantly up-regulated the expression of the well-known downstream protein P27 and down-regulated that of AR. Consistently, DHT treatment increased the activity of ARR3-Luc, while knockdown of Skp2 remarkably decreased it in the C4-2 and 22RV1 cells (P < 0.05). In addition, significantly higher expressions of Skp2 and AR were observed in the CRPC than in the naïve specimens (P < 0.05), with a positive correlation between the two proteins (r = 0.658 1, P < 0.05). CONCLUSION: Skp2 can enhance the expression and transcription activity of the AR protein in CRPC cells or tissues and is promising to be a critical molecular therapeutic target.

Tetrandrine suppresses proliferation, induces apoptosis, and inhibits migration and invasion in human prostate cancer cells.

Tetrandrine (TET), a traditional Chinese medicine, exerts remarkable anticancer activity on various cancer cells. However, little is known about the effect of TET on human prostate cancer cells, and the mechanism of function of TET on prostate cancer has not yet been elucidated. To investigate the effects of TET on the suppression of proliferation, induction of apoptosis, and inhibition of migration and invasion in human prostate cancer cell lines, DU145 and PC-3. Inhibition of growth was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and clone formation assay, and flow cytometry analysis was performed to detect the induction of apoptosis. Activation of poly (ADP-ribose) polymerase, caspase-3, Akt, phospho-Akt, Bcl-2, and Bax was analyzed by Western blotting. Wound healing assay and transwell migration assay were used to evaluate the effect of TET on migration and invasion of cancer cells. TET inhibited the growth of DU145 and PC-3 cells in a dose- and time-dependent manner. Cell cloning was inhibited in the presence of TET in DU145 and PC-3 cells. TET suppressed the migration of DU145 and PC-3 cells. Transwell invasion assay showed that TET significantly weakened invasion capacity of DU145 and PC-3 cells. TET exhibited strong inhibitory effect on proliferation, migration, and invasion of prostate cancer cells. In addition, TET induced apoptosis in a dose-dependent manner by activating the caspase cascade and inhibiting phosphoinositide 3-kinase-Akt signal pathway. The accumulating evidence suggests that TET could be a potential therapeutic candidate against prostate cancer in a clinical setting.

[Synthesis and biological evaluation of novel pleuromutilin derivatives with nitrogen-containing heterocycles as antibacterial agents].

A series of new pleuromutilins derivatives were designed and synthesized through coupling 2-aminothiazole ring of WL001 with different nitrogen-containing substituted heterocycles in the side chain. Their biological activities were evaluated against both Gram-positive and Gram-negative clinical bacteria in vitro Most new compounds displayed specificity to certain strain of bacteria. Particularly, compounds with saturated nitrogen-containing heterocycles exhibited significant antibacterial activities (0.062 5-8 µg · mL(-1)) superior or similar to those of amoxicillin, tiamulin and levofloxcin. Furthermore, treatment with 15a and 15b having piperidine or morpholine residues also could effectively inhibit Gram-negative bacteria. Therefore, our novel findings may provide a new insight into the design of novel pleuromutilin derivatives and lay the basis for further studies on the treatment of drug-resistance of pathogenic bacteria.

[DAB2IP expression in bladder transitional cell carcinoma and its correlation with clinical outcome].

OBJECTIVE: To investigate the expression of DAB2IP in bladder transitional cell carcinoma (BTCC) and its correlation with clinical characteristics and prognosis of BTCC patients. METHODS: Immunohistochemical staining was applied to detect DAB2IP protein level in 79 cases of TCCB tissues and 11 cases of normal bladder tissues, and the relationships of the staining results with pathological grade, stage, lymph node metastasis, gender, age and the 3-year survival rate of the patients were analyzed. RESULTS: The expression of DAB2IP in BTCC tissues was significantly lower than that in normal bladder epithelium, and the expression score and rate of DAB2IP in the high-grade, invasive and metastatic BTCC were significantly lower than those in low-grade, superficial and non-metastatic BTCC (P < 0.05). The 3-year survival rate of the patients with high DAB2IP expression was significantly higher than that of the patients with low DAB2IP expression. CONCLUSION: DAB2IP may be one of the important inhibitory factors during the occurrence and progression of BTCC.

Testosterone regulates keratin 33B expression in rat penis growth through androgen receptor signaling.

Androgen therapy is the mainstay of treatment for the hypogonadotropic hypogonadal micropenis because it obviously enhances penis growth in prepubescent microphallic patients. However, the molecular mechanisms of androgen treatment leading to penis growth are still largely unknown. To clarify this well-known phenomenon, we successfully generated a castrated male Sprague Dawley rat model at puberty followed by testosterone administration. Interestingly, compared with the control group, testosterone treatment stimulated a dose-dependent increase of penis weight, length, and width in castrated rats accompanied with a dramatic recovery of the pathological changes of the penis. Mechanistically, testosterone administration substantially increased the expression of androgen receptor (AR) protein. Increased AR protein in the penis could subsequently initiate transcription of its target genes, including keratin 33B (Krt33b). Importantly, we demonstrated that KRT33B is generally expressed in the rat penis and that most KRT33B expression is cytoplasmic. Furthermore, AR could directly modulate its expression by binding to a putative androgen response element sequence of the Krt33b promoter. Overall, this study reveals a novel mechanism facilitating penis growth after testosterone treatment in precastrated prepubescent animals, in which androgen enhances the expression of AR protein as well as its target genes, such as Krt33b.

Downregulation of mTOR by lentivirus inhibits prostate cancer cell growth.

Prostate cancer, one of the most lethal forms of urinary system cancer, remains resistant to currently available treatments. Therefore, novel mechanism and target-based approaches are needed for the management of this neoplasm. PI3K/AKT signaling pathway activation correlates with human prostate cancer progression and metastasis. However, the role of mTOR in prostate cancer is not well-established. Here, we demonstrate that mTOR is over-expressed in both clinical tissue specimens and cultured human prostate cancer cells when compared to normal prostate tissues, respectively. Further, mTOR gene knockdown via lentivirus mediated mTOR specific shRNA resulted in a significant decrease in the viability and growth of prostate cancer cells without affecting normal human prostate cells. In addition, mTOR inhibition resulted in a significant i) decrease in 4EBP1, S6K, PI3K and AKT protein, ii) increase in PARP protein of prostate cancer cells. Most importantly, mTOR inhibition triggered apoptosis and suppressed pancreatic carcinoma growth in vivo in a mouse xenograft model. We suggest that targeting of mTOR may be a viable approach for the treatment of prostate cancer.

Relationships among androgen receptor CAG repeat polymorphism, sex hormones and penile length in Han adult men from China: a cross-sectional study.

This study aimed to investigate the correlations among androgen receptor (AR) CAG repeat polymorphism, sex hormones and penile length in healthy Chinese young adult men. Two hundred and fifty-three healthy men (aged 22.8 ± 3.1 years) were enrolled. The individuals were grouped as CAG short (CAG S ) if they harbored repeat length of ≤ 20 or as CAG long (CAG L ) if their CAG repeat length was >20. Body height/weight, penile length and other parameters were examined and recorded by the specified physicians; CAG repeat polymorphism was determined by the polymerase chain reaction (PCR) method; and the serum levels of the sex hormones were detected by radioimmunoassay. Student's t-test or linear regression analysis was used to assess the associations among AR CAG repeat polymorphism, sex hormones and penile length. This investigation showed that the serum total testosterone (T) level was positively associated with the AR CAG repeat length (P = 0.01); whereas, no significant correlation of T or AR CAG repeat polymorphism with the penile length was found (P = 0.593). Interestingly, an inverse association was observed between serum prolactin (PRL) levels and penile length by linear regression analyses (ß= -0.024, P = 0.039, 95% confidence interval (CI): -0.047, 0). Collectively, this study provides the first evidence that serum PRL, but not T or AR CAG repeat polymorphism, is correlated with penile length in the Han adult population from northwestern China.

Benzylidene 2-aminoimidazolones derivatives: synthesis and in vitro evaluation of anti-tumor carcinoma activity.

A series of benzylidene 2-aminoimidazolones derivatives were synthesized. Most compounds displayed strong inhibitory activity on the proliferation of human HepG2 cells in vitro. The active compounds were further evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay against five human cancer cell lines in vitro. Compound 2b exhibited the strongest antitumor activities with IC50 values ranging from 12.87-17.10 µM which were nearly 1-3.5 fold less than that of 5-FU (IC50=18.39-56.12 µM) in vitro. Furthermore, compound 2b could induce SMMC-7721 cell apoptosis in a dose-dependent manner. Therefore, our novel findings may provide a new framework for the design of new benzylidene 2-aminoimidazolones derivatives for the treatment of cancer.

[Changes of intracellular cholesterol metabolism in neuroendocrine differentiation of prostate cancer and their significance].

OBJECTIVE: To explore the roles of intracellular cholesterol metabolism in neuroendocrine (NE) differentiation of prostate cancer based on an androgen-independent prostate cancer NE cell model induced by androgen deprivation. METHODS: LNCaP cells were cultured in androgen-depleted medium, and NE phenotypes were identified by observing the changes in cell morphology, molecular markers (SgIII, NSE and CgA) and cell proliferation. The expression and distribution of cholesterol and Sg III were determined by immunofluorescence staining. The expressions of the key genes LDL-R, SREBP-1 and SREBP-2 involved in cholesterol synthesis and uptake were detected by semi-quantitative RT-PCR. RESULTS: The LNCaP cells showed shrinking bodies and extending axons after androgen deprivation, and all the molecular markers, such as Sg III, NSE and CgA, significantly increased in a time-dependent manner, while the cell proliferation was obviously inhibited (P < 0.05). The cholesterol distribution in the LNCaP cells after NE differentiation presented remarkable aggregation at the axon terminals. However, there were no significant differences in the expression of cholesterol between the two types of cells, nor in the changes of the expressions of key genes LDL-R, SREBP-1 and SREBP-2 involved in cholesterol synthesis and uptake (P > 0.05). CONCLUSION: Transient androgen depletion could successfully induce NE differentiation of LNCaP cells, and the intracellular cholesterol could re-distribute into axon terminals to enhance the formation of neurosecretory granules.

Prostate-targeted mTOR-shRNA inhibit prostate cancer cell growth in human tumor xenografts.

OBJECTIVE: To construct a recombinant lentivirus vector driven by the PSMA promoter carrying mTOR-shRNA, and to obtain the effect on the mTOR gene silencing in human prostate cancer xenografts. METHODS: The complimentary oligos of small interference RNA (siRNA) with hairpin structures targeting the mTOR gene and a negative control were synthesized, then ligated with pLV-PSMA-promoter vector and sequenced. The recombinant vectors were then transfected with viral packaging mix into 293T cells, viral supernatant was harvested to determine the titer. Prostate cancer cells infected by virus were harvested and the expression of mTOR (LV-PSMA-shmTOR), target proteins and cell growth were detected by reverse transcription-PCR (RT-PCR), Western blot and MTT separately. In established tumors derived from human prostate cancer cells, concentrated LV-PSMA-shmTOR lentivirus was injected intravenously in the tail vein of C4-2b tumor bearing female severe combined immunodeficient (SCID) mice. Tumor volume and immunohistochemistry was assessed. RESULTS: Sequencing data showed that the constructed plasmids contained the correct sequences of mTOR siRNA transcript templates. A vector producing cell line 293T was established, and the titer for transfection was obtained. RT-PCR, Western blot and MTT analyses demonstrated that mTOR shRNA expression construct could suppress the expression of mTOR and inhibit the prostate cancer cell growth, specially. The tumor growth was suppressed in nude mouse. CONCLUSION: A PSMA driven lentivirus mediated siRNA targeting mTOR gene was successfully constructed, which decreased the expression of mTOR and induced the prostate cancer cell growth in vitro and in vivo. It has set up a research platform for the gene therapy of tumors which take mTOR as the target in the prostate cancer field.