Extracellular matrix protein 1 promotes cell metastasis and glucose metabolism by inducing integrin β4/FAK/SOX2/HIF-1α signaling pathway in gastric cancer

Extracellular matrix protein 1 (ECM1) is related to strong invasiveness and poor prognosis in major malignancies, but the underlying mechanism remains unknown. Here we aimed to elucidate the function of ECM1 on cell metastasis and glucose metabolism in gastric cancer (GC). The level of ECM1 in sera and tissues of patient with GC were positively correlated with tumor invasion and recurrence. Genetic manipulation of ECM1 expression affected cell metastasis and glucose metabolism in GC cell lines. Enhanced ECM1 expression facilitated gene expression levels associated with epithelial-mesenchymal transition (EMT) and glucose metabolism. Interestingly, our results indicated that ECM1 directly interacted with integrin β4 (ITGB4) and activated ITGB4/focal adhesion kinase (FAK)/glycogen synthase kinase 3β signaling pathway, which further induced the expression of transcription factor SOX2. Aberrant expression of SOX2 altered gene expression of EMT factors and glucose metabolism enzymes. Furthermore, SOX2 enhanced hypoxia-inducible factor α (HIF-1α) promoter activity to regulate glucose metabolism. The micro-positron emission tomography/computed tomography imaging of xenograft model showed that ECM1 substantially increased ¹⁸F-fluorodeoxyglucose uptake in xenograft tumors. Using in vivo mouse tail vein injection experiments, ECM1 was also found to increase in lung surface metastasis. These findings provide evidence that ECM1 regulates GC cell metastasis and glucose metabolism by inducing ITGB4/FAK/SOX2/HIF-1α signal pathway and have important implications for the development of therapeutic target to prevent tumor metastasis and recurrence.

[Expression of ER and PR in the endometrium of patients with intrauterine adhesions]

Objective: To estimate the expression of ER and PR in the endometrium of both intrauterine adhesions (IUA) and non-IUA specimens. Methods: The endometrium specimens from patients undergoing hysteroscopy for confirmed moderate IUA (n=20: 10 in proliferative phase, and 10 in secretory phase) were enrolled as the IUA group in Beijing Obstetrics and Gynecology Hospital from October 2014 to August 2015. The specimens scheduled for hysteroscopy due to infertility were recruited into the control group (n=26: 13 in proliferative phase, and 13 in secretory phase). Immunohistochemistry and quantificational real-time PCR (qRT-PCR) were used to detect the expression of ER-α, ER-β and PR in endometrium with different menstrual period in both groups. Results: (1) Location: in both groups, the expression of ER-α, ER-β and PR appeared in the endometrial glandular epithelial cells and the stromal cells of the endometrium. The positive brown granules of ER-α, ER-β and PR appeared mainly in cell nucleus. (2) ER-α and ER-β in the endometrium: the protein expression of ER-α and ER-β in IUA group (proliferative phase: 0.657±0.028, 0.493±0.023; secretory phase: 0.537±0.020, 0.365±0.031) were significantly higher than those of control group (proliferative phase: 0.586±0.025, 0.437±0.022; secretory phase: 0.459±0.025, 0.323±0.017; all P<0.01). And the ER-α and ER-β mRNA expressions in IUA group were 2.524±0.296, 1.947±0.339, higher than those of control group in the proliferative phase (all P<0.01), and in the secretory phase (1.977±0.333, 1.345±0.292) were also higher than those in the control group (all P<0.01). (3) PR in the endometrium: the protein expression of PR was not significantly different between IUA group (proliferative phase: 0.248±0.025, secretory phase: 0.194±0.024) and control group (proliferative phase: 0.234±0.019, secretory phase: 0.186±0.020; P=0.162, 0.359). Meanwhile, there were no statistical differences in the mRNA expression of PR in both groups with different menstrual period (proliferative phase: 1.144±0.384 versus 0.981±0.306, secretory phase: 0.763±0.237 versus 0.631±0.203; P=0.270, 0.166). (4) ER and PR expression in menstrual cycles: the expression of ER-α, ER-β and PR in the IUA group changed with the menstrual cycles, and their expression in the proliferative phase were higher than those in the secretory phase (all P<0.05). Conclusions: The expression of ER-α and ER-β in the endometrium of IUA patients changes with menstrual cycle, and are higher compared with those in normal endometrium. No difference is found in the PR expression between the two groups.

Ontogeny of Hepatic Drug Transporters as Quantified by LC-MS/MS Proteomics

Protein expression of major hepatic uptake and efflux drug transporters in human pediatric (n = 69) and adult (n = 41) livers was quantified by liquid chromatography / tandem mass spectroscopy (LC-MS/MS). Transporter protein expression of OCT1, OATP1B3, P-gp, and MRP3 was age-dependent. Particularly, significant differences were observed in transporter expression (P < 0.05) between the following age groups: neonates vs. adults (OCT1, OATP1B3, P-gp), neonates or infants vs. adolescents and/or adults (OCT1, OATP1B3, and P-gp), infants vs. children (OATP1B3 and P-gp), and adolescents vs. adults (MRP3). OCT1 showed the largest increase, of almost 5-fold, in protein expression with age. Ontogenic expression of OATP1B1 was confounded by genotype and was revealed only in livers harboring SLCO1B1*1A/*1A. In livers >1 year, tissues harboring SLCO1B1*14/*1A showed 2.5-fold higher (P < 0.05) protein expression than SLCO1B1*15/*1A. Integration of these ontogeny data in physiologically based pharmacokinetic (PBPK) models will be a crucial step in predicting hepatic drug disposition in children.

Effects of miR-26a on the expression of Beclin 1 in retinoblastoma cells

The aim of this study was to evaluate the effects of miR-26a on Beclin 1 expression in retinoblastoma (RB) cell lines (Y79 and WERi-RB-1). RB cells were transfected with miR-26a mimic, antagomir-26a, or control mimic. The Beclin 1 mRNA and protein levels were detected by quantitative polymerase chain reaction and western blot, respectively. The activity of Beclin 1 3ꞌ-UTR reporter gene was detected with the luciferase assay. After transfection with miR-26a mimic, Beclin 1 mRNA and protein levels as well as the activity of the 3'-UTR reporter gene decreased. However, all were increased upon inhibition of miR-26a with antagomir-26a. Beclin 1 is the target of miR-26a in human RB cell lines Y79 and WERi-RB-1, and miR-26a inhibits the expression of Beclin 1 by reducing its mRNA and protein levels.

Relationship between CYP17 gene polymorphisms and risk of prostate cancer

Cytochrome P450 17a-hydroxylase (CYP17) plays a critical role in androgen biosynthesis. Polymorphisms of the CYP17 promoter have been proposed as risk factors for prostate cancer; however, some studies have produced inconclusive or controversial results. We investigated the relationship between polymorphisms of the CYP17 gene and the risk of prostate cancer. A total of 176 patients with prostate cancer were enrolled in the study, and 168 healthy individuals acted as the control group. The participants were divided into those <71 years old and those ≥71 years old. Restriction fragment length polymorphism-polymerase chain reaction was used to confirm the genotype of CYP17 in the samples. The prostate-specific antigen (PSA) concentrations were also measured in all subjects. When T/C and C/C were compared with T/T, the ORs were 0.478 (P = 0.489) and 0.814 (P = 0.367), respectively. There was no significant difference in PSA concentration among the three genotypes in the <71 group, whereas there were statistically significant differences in the ≥71 group (P = 0.003 and 0.012, respectively). There was no significant difference in free PSA and total PSA levels between the three groups and the control group. The T/C and C/C genotypes were not associated with the risk of prostate cancer, and there were no significant differences between them. In the ≥71 group, the T/C and C/C genotypes were closely associated with prostate cancer, which suggests that the CYP17 gene might be a risk factor for prostate cancer in males of advanced age.

Construction of a hepatocellular carcinoma cell line that stably expresses stathmin with a Ser25 phosphorylation site mutation

We constructed hepatocellular carcinoma (HCC) cells that stably express stathmin with a Ser25 phosphorylation site mutation (stathmin S25A). We used the polymerase chain reaction for site-directed mutagenesis, constructed a stathmin S25A plasmid, and verified the results by restriction enzyme cleavage and sequencing technology. Using the liposome transfection method, stathmin wild-type and S25A HCCLM6 cells were established, which were identified by western blotting. The sequencing report of the stathmin S25A plasmid showed that stathmin serine at position 25 had mutated into alanine. Stable cells transfected with stathmin wild-type and S25A plasmids were constructed. Using western blotting, we confirmed that the expression level of stathmin pS25 in the stathmin S25A cells was reduced than that in the stathmin wild-type and HCCLM6 control cells (P < 0.05). We constructed stathmin S25A HCCLM6 cells, which offer an experimental model for further investigation of the molecular mechanism of stathmin phosphorylation in hepatocarcinogenesis.

Metabolic targeting of oncogene MYC by selective activation of the proton-coupled monocarboxylate family of transporters

Deregulation of the MYC oncogene produces Myc protein that regulates multiple aspects of cancer cell metabolism, contributing to the acquisition of building blocks essential for cancer cell growth and proliferation. Therefore, disabling Myc function represents an attractive therapeutic option for cancer treatment. However, pharmacological strategies capable of directly targeting Myc remain elusive. Here, we identified that 3-bromopyruvate (3-BrPA), a drug candidate that primarily inhibits glycolysis, preferentially induced massive cell death in human cancer cells overexpressing the MYC oncogene, in vitro and in vivo, without appreciable effects on those exhibiting low MYC levels. Importantly, pharmacological inhibition of glutamine metabolism synergistically potentiated the synthetic lethal targeting of MYC by 3-BrPA due in part to the metabolic disturbance caused by this combination. Mechanistically, we identified that the proton-coupled monocarboxylate transporter 1 (MCT1) and MCT2, which enable efficient 3-BrPA uptake by cancer cells, were selectively activated by Myc. Two regulatory mechanisms were involved: first, Myc directly activated MCT1 and MCT2 transcription by binding to specific recognition sites of both genes; second, Myc transcriptionally repressed miR29a and miR29c, resulting in enhanced expression of their target protein MCT1. Of note, expressions of MCT1 and MCT2 were each significantly elevated in MYCN-amplified neuroblastomas and C-MYC-overexpressing lymphomas than in tumors without MYC overexpression, correlating with poor prognosis and unfavorable patient survival. These results identify a novel mechanism by which Myc sensitizes cells to metabolic inhibitors and validate 3-BrPA as potential Myc-selective cancer therapeutics.

Evaluation of cytotoxicity of some common ophthalmic drugs

The article "Evaluation of cytotoxicity of some common ophthalmic drugs" by M. Li, X.-M. Chen, J.-J. Liu, D.-M. Wang, L. Gan, X. Lv, Y. Qiao, published in Eur Rev Med Pharmacol Sci 2015; 19 (11): 1945-1950 has been withdrawn.

ISL1 Is Necessary for Maximal Thyrotrope Response to Hypothyroidism

ISLET1 is a homeodomain transcription factor necessary for development of the pituitary, retina, motor neurons, heart, and pancreas. Isl1-deficient mice (Isl1(-/-)) die early during embryogenesis at embryonic day 10.5 due to heart defects, and at that time, they have an undersized pituitary primordium. ISL1 is expressed in differentiating pituitary cells in early embryogenesis. Here, we report the cell-specific expression of ISL1 and assessment of its role in gonadotropes and thyrotropes. Isl1 expression is elevated in pituitaries of Cga(-/-) mice, a model of hypothyroidism with thyrotrope hypertrophy and hyperplasia. Thyrotrope-specific disruption of Isl1 with Tshb-cre is permissive for normal serum TSH, but T4 levels are decreased, suggesting decreased thyrotrope function. Inducing hypothyroidism in normal mice causes a reduction in T4 levels and dramatically elevated TSH response, but mice with thyrotrope-specific disruption of Isl1 have a blunted TSH response. In contrast, deletion of Isl1 in gonadotropes with an Lhb-cre transgene has no obvious effect on gonadotrope function or fertility. These results show that ISL1 is necessary for maximal thyrotrope response to hypothyroidism, in addition to its role in development of Rathke's pouch.

Controllable synthesis of porous iron–nitrogen–carbon nanofibers with enhanced oxygen reduction electrocatalysis in acidic medium

Porous Fe–N–C nanofibers were synthesized as non-precious metal electrocatalysts with a 20 times enhancement in oxygen reduction performance.

Evaluation of cytotoxicity of some common ophthalmic drugs

OBJECTIVE

The study was aimed at evaluating the in vitro cytotoxicity of some commonly used drugs in ophthalmology. Hydrocortisone sodium succinate, Dexamethasone sodium phosphate, 5-Fluorouracil, Tobramycin and Pilocarpine nitrate are frequently used in various indications involving eye care, and the aim was to test the safety of these in cell culture.

MATERIALS AND METHODS

The in vitro cytotoxicity was carried out on the NIH 3T3 cell line by the Sulforhodamine B (SRB) assay.

RESULTS

With the exception of 5-Fluorouracil, none of the other drugs demonstrated appreciable cytotoxicity up to high concentrations of 200 µg/ml at 48 hours of drug exposure.

CONCLUSIONS

Hydrocortisone sodium succinate, Dexamethasone sodium phosphate, Tobramycin and Pilocarpine nitrate were confirmed to be non-cytotoxic while 5-Fluorouracil was highly cytotoxic especially at 48 hours at very low concentrations.