Short-term exposure to gossypol causes reversible reproductive toxicity and nephrotoxicity in mice / 南方医科大学学报

OBJECTIVE@#To study the toxic effects of short-term exposure to gossypol on the testis and kidney in mice and whether these effects are reversible.@*METHODS@#Twenty 7 to 8-week-old male mice were randomized into blank control group, solvent control group, gossypol treatment group and drug withdrawal group. In the former 3 groups, the mice were subjected to daily intragastric administration of 0.3 mL of purified water, 1% sodium carboxymethylcellulose solution, and 30 mg/mL gossypol solution for 14 days, respectively; In the drug withdrawal group, the mice were treated with gossypol solution in the same manner for 14 days followed by treatment with purified water for another 14 days. After the last administration, the mice were euthanized and tissue samples were collected. The testicular tissue was weighed and observed microscopically with HE and PAS staining; the kidney tissue was stained with HE and examined for mitochondrial ATPase activity.@*RESULTS@#Compared with those in the control group, the mice with gossypol exposure showed reduced testicular seminiferous epithelial cells with rounded seminiferous tubules, enlarged space between the seminiferous tubules, interstitium atrophy of the testis, and incomplete differentiation of the spermatogonia. The gossypol-treated mice also presented with complete, non-elongated spermatids, a large number of cells in the state of round spermatids, and negativity for acrosome PAS reaction; diffuse renal mesangial cell hyperplasia, increased mesangial matrix, and adhesion of the mesangium to the wall of the renal capsule were observed, with significantly shrinkage or even absence of the lumens of the renal capsules and reduced kidney mitochondrial ATPase activity. Compared with the gossypol-treated mice, the mice in the drug withdrawal group showed obvious recovery of morphologies of the testis and the kidney, acrosome PAS reaction and mitochondrial ATPase activity.@*CONCLUSIONS@#Shortterm treatment with gossypol can cause reproductive toxicity and nephrotoxicity in mice, but these toxic effects can be reversed after drug withdrawal.

Prospects for histone deacetylase inhibitors as antidepressants / 药学学报

Depression is a serious mental illness with a high incidence. At present, we do not fully understand the specific pathological mechanisms of depression, and the efficacy of drug treatments is very limited. Recent studies have shown that epigenetic changes that occur in specific brain regions may be a key mechanism by which environmental factors to interact with individuals to influence the risk of depression. Therefore, drugs that target epigenetic regulation may become a new direction for the development of antidepressants. Histone deacetylase inhibitors (HDACi) are a class of compounds that inhibit histone deacetylase activity, which has been reported to be associated with depression; this article addresses the use of HDACi in preclinical studies, and their potential therapeutic role and limitations of use in depression.

Progress in research of N-acetylaspartate in central nervous system / 药学学报

italic>N-Acetylaspartate (NAA) is a highly abundant brain metabolite. Nowadays, as an important marker reflecting the function of nervous system, NAA is widely used in the results analysis of nuclear magnetic resonance spectroscopy (1H MRS). NAA is synthesized in mitochondria of neurons and metabolized in oligodendrocytes. Additionally, NAA may be converted to the dipeptide N-acetylaspartylglutamate (NAAG), and catabolized into NAA and glutamate in astrocytes. NAA is related to a variety of central nervous system diseases, including Canavan disease, multiple sclerosis, depression, schizophrenia and other mental diseases. Therefore, NAA may be a biomarker of these diseases, and its related enzymes may be used as therapeutic targets for drug screening. Here, we combined the current research on the molecular mechanisms of NAA to reveal the process of NAA generation, metabolism and transport in the brain, explain the possible physiological effects of NAA and discuss its relationship with central nervous system diseases, explore the prospect of NAA in disease prediction and diagnosis, as well as the targeted treatment that may become the breakthrough of refractory diseases.

Effects of endoplasmic reticulum stress-induced apoptosis in thyroid injury caused by fluoride in rat / 中华预防医学杂志

Objective@#To explore the effects of endoplasmic reticulum stress-induced apoptosis in thyroid injury of rats caused by excessive fluoride intake.@*Methods@#All 40 Wistar rats were randomly divided into four groups, control group, low fluoride group, medium fluoride group and high fluoride group. The rats in control group were fed with tap water (fluoride concentration=0.344 mg/L) and the experimental rats were fed with the water contaminated fluoride with the dose of 5, 10 and 20 mg/L. 10 rats (female: male=1∶1) in each group were sacrificed after 8 months of exposure through drinking water. The contents of urine fluoride were detected by fluorine ion selective electrode method. Morphology of thyroid was observed through light microscope and apoptosis in thyroid were detected by the terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay. The mRNA and protein expressions of glucose-regulated protein 78 (GRP78) and C/EBP homologous protein (CHOP) were analyzed by RT-PCR and immunohistochemistry respectively, and results were compared among groups.@*Results@#The contents of urine fluoride in all fluoride treated groups were separately (4.74±1.88), (7.70±2.82) and (10.50±2.92) mg/L, which were gradually higher than that of control group (2.23±0.54) mg/L (P<0.05). Morphological changes were found in thyroid tissues of fluoride treated groups, thyroid follicular hyperplasia or even no cavity cell clusters were observed. Apoptosis in thyroid were notably increased in fluoride treated groups. The mRNA expression levels of GRP78 in all fluoride treated groups were separately 1.30±0.42, 1.39±0.29 and 1.50±0.27, which were significantly higher than that of control group (0.93±0.24) (P<0.05). And the mRNA expression levels of CHOP in medium and high fluoride groups were separately 1.17±0.29 and 1.30±0.26, which were significantly higher than that of control group (0.91±0.20) (P<0.05). The protein expression levels of GRP78 and CHOP in medium and high fluoride groups were respectively 29.68±4.04, 29.90±3.74 and 4.05±1.62, 4.44±1.81, which were significantly higher than those in the control group (separately 23.80±6.36, 2.27±0.89) (P<0.05).@*Conclusion@#Excessive-fluoride intake can induce thyroid injury, and endoplasmic reticulum stress-induced apoptosis might be involved in the injury.

Effect of down-regulation of X-box binding protein 1 gene expression on viability and apoptosis of glioma cells / 中国病理生理杂志

AIM:To investigate the effect of down-regulation of X-box binding protein 1(XBP1)expression on the viability and apoptosis of glioma cells.METHODS:The mRNA expression of XBP1 in the glioma tissues was de-tected by qPCR.Small interfering RNA(siRNA)interfering with XBP1 expression(XBP1-siRNA)was transfected into human brain glioma U251 cells.At the same time,control group(the cells without special treatment)and negative control (NC-siRNA)group(transfected with siRNA without any interference)were set up.The mRNA expression of XBP1 in the 3 groups 48 h after transfection was detected by qPCR.The protein levels of XBP1, proliferating cell nuclear antigen (PCNA),B-cell lymphoma/leukemia-2(Bcl-2),Bcl-2-associated X protein(Bax),cyclin D1(cyclin D1), phosphati-dylinositol 3-kinase(PI3K)and phosphorylated Akt(p-Akt)were determined by Western blot.The cell viability was measured by CCK-8 assay.The cell cycle distribution and apoptosis were analyzed by flow cytometry.RESULTS:The ex-pression level of XBP1 in the glioma tissues was significantly higher than that in the tumor adjacent tissues(P<0.05). The XBP1 expression at mRNA and protein levels was significantly decreased in the cells transfected with XBP1-siRNA(P<0.05).No statistically significant difference of the cell viability, cell cycle, apoptotic rate and the protein levels of PCNA,Bcl-2,Bax,cyclin D1,PI3K and p-Akt between NC-siRNA group and control group was observed.Compared with control group,the cell viability, S-phase cells and the protein levels of PCNA, Bcl-2, cyclin D1, PI3K, and p-Akt in XBP1-siRNA group were decreased significantly, and the apoptotic rate, G0/G1-phase cells and Bax protein expression were significantly increased(P<0.05).CONCLUSION:Down-regulation of XBP1 gene expression in brain glioma cells reduces the viability of cancer cells,blocks the cells in G1phase and promote apoptosis.The mechanism is related to the inhibition of PI3K/Akt signaling pathway.

Gray mold disease of Paris polyphylla var. yunnanensis and its pathogen identification / 中国中药杂志

Gray mold disease is one of the most important diseases of planted Paris polyphylla var. yunnanensis, the disease appeared primarily as blossom blights and fruit rots, but also as stem rots, leaf rots.In this study, the pathogenetic fungi was isolated from plant tissue or sclerotia that covering the fruit of diseased P. polyphylla var. yunnanensis, the pathogen was certified according to Koch's Postulation. The pathogen produced abundant black, irregular sclerotia on surface of diseased plants and potato dextrose agar. The conidiophores and clusters of oval conidia resembled a grape-like cluster, the size of conidia was 9.70-13.70 μm [average of (11.32±0.82)μm]×7.05-9.12 μm [average of (8.24±0.48)μm], the microconidia produced on potato dextrose agar were spherical,and the size was （3.34±0.31） μm,the pathogen was identified as Botrytis sp based on morphological characteristics. The DNA sequence analysis of the G3PDH, HSP60, RPB2 genes placed the pathogen in a single clade that outside defined species of Botrytis, so the pathogen could be identified as a new species of Botrytis. The pathogen requires 20 °C, pH 8, darkness or low light condition for the best growth.

Correction: Outcome of Percutaneous Transforaminal Endoscopic Lumbar Surgery in >60-Year-Old Patients with Low Back Pain

Correction for the Results section of the Abstract is needed. There was a mistake in the numerical values of Results section of the Abstract.

New immunotherapy strategies in breast cancer / 中国药理学通报

Breast cancer is the principal cause of death in malig-nancy women , usually treated with the combination of surgery , chemotherapy , radiotherapy and endocrinotherapy .With the de-velopment of cell biology , molecular biology , immunology, im-munotherapy becomes a new field of breast cancer treatment .In this review, we discuss new findings in breast cancer immuno-therapy , including recent successes with bispecific antibodies and immune checkpoint blockade .We also discuss therapeutic cancer vaccines and highlight several additional immunotherapy modalities in early stages of development .

A Novel Functional Missense Mutation p.T219A in Type 1 Gaucher's Disease / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Gaucher's disease (GD) is an autosomal recessive disorder caused by a deficiency of acid β-glucosidase (glucocerebrosidase [GBA]) that results in the accumulation of glucocerebroside within macrophages. Many mutations have been reported to be associated with this disorder. This study aimed to discover more mutations and provide data for the genetic pattern of the gene, which will help the development of quick and accurate genetic diagnostic tools for this disease.</p><p><b>METHODS</b>Genomic DNA was obtained from peripheral blood leukocytes of the patient and Sanger sequencing is used to sequence GBA gene. Sequence alignments of mammalian β-GBA (GCase) and three-dimensional protein structure prediction of the mutation were made. A construct of this mutant and its compound heterozygous counterpart were used to measure GCase in vitro.</p><p><b>RESULTS</b>GCase is relatively conserved at p.T219A. This novel mutation differs from its wild-type in structure. Moreover, it also causes a reduction in GCase enzyme activity.</p><p><b>CONCLUSION</b>This novel mutation (c.655A>G, p.T219A) is a pathogenic missense mutation, which contributes to GD.</p>

The changes of monocarboxylate transporter-2 in spinal cord horn in a rat model of chronic inflammatory pain / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To investigate the changes in the levels of monocarboxylate transporter-2 in spinal cord horn in a rat model of chronic inflammatory pain.</p><p><b>METHODS</b>Male SD rats weighting 180 - 220 g were randomly divided into two groups(n = 48): normal saline group (NS group), complete Freund's adjuvant group (CFA group). Rats were given injections of CFA 100 µl in left hind paw in group CFA, and an equal volume of saline was given injection in group NS. Mechanical withdraw threshold(MWT) and thermal withdraw latency(TWL) were measured at before injection(T0 and 3 h, 1 d, 3 d, 7 d, 14 d, and 21 d after injection(T1-7). Four rats were chosen from each group at T0-7 and sacrificed, and L4-5 segments of the spinal cord horn were removed for measurement of the expression of monocarboxylate transporter-2 by Western blot analysis.</p><p><b>RESULTS</b>In CFA group, mechanical hyperalgesia and allodynia appeared on the 3 h after CFA injection, then until the day 14. The expression of monocarboxylate transporter-2 in the spinal dorsal horn of rats in CFA group was significantly higher than that in normal control group at T1-6(P <0.05). The protein level of monocarboxylate transporter-2 was apparently correlated with MWT and TWL(P <0.01 and P <0.05) in CFA group.</p><p><b>CONCLUSION</b>The level of monocarboxylate transporter-2 in spinal dorsal horn is significantly increased in a rat model of chronic inflammatory pain and the change may involve in the formation and maintenance of central sensitization in spinal cord of chronic inflammatory uain.</p>

Construction of acid-sensitive potassium channel-3 eukaryotic expression plasmid and its express in SH-SY5Y cells / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To construct the acid-sensitive potassium hannel-3(TASK3) eukaryotic expression plasmid and to establish a stable SH-SY5Y cell line expressing enhanced green fluorescent protein (EGFP)-tagged TASK3.</p><p><b>METHODS</b>TASK3 coding region was subcloned into pEGFP-N1 plasmid to construct a recombinant vector alled pEGFP-TASK3. The correct recombinant expressing plasmid was transfected with X-feet transfection reagent to SH-SY5Y cells. The cell line stably expressiing EGFP tagged-TASK3 gene was established by screening with antibiotic G418 and fluorescence microscope. The expression and localization of the EGFP tagged-TASK3 fusion protein was detected by Western blot and confocal microscope. Exposure of the SH-SY5Y cell line expressing stably TASK3-eGFP fusion proteins was exposed to different pH media (7.0, 6.7, 6.4, 6.1) for 24 h, the cell viability was assessed with cell counting Kit-8 (CCK-8).</p><p><b>RESULTS</b>All the results of identification by PCR, digestion with restriction endonuclease and sequencing indicated that the recombinant eukaryotic expression plasmid pEGFP-TASK3 was constructed correctly. The stable SH-SY5Y cell line expressing EGFP tagged-TASK3 fusion protein was successfully established. Exposure of the wild type SH-SY5Y cells and the stable SH-SY5Y-GFP tag-TASK3 cell line to different pH media (7.0, 6.7, 6.4, 6.1) for 24 h, the cell viability of two group cells significantly reduced with pH declining, and the difference was statistically significant (P < 0.05). Compared with wild type SH-SY5Y cells, the cell viability of stable SH-SYSY-GFP tag-TASK3 cell line increased significantly with the same pH media, and the difference was statistically significant (P < 0.05).</p><p><b>CONCLUSION</b>The eukaryotic expression vector pEGFP-TASK3 is successfully constructed and the cell line stably expressing TASK3-eGFP fusion is established which is important for their fundamental research and potential applications.</p>

Neuroprotective effect of progesterone on focal cerebral ischemia/reperfusion injury in rats and its mechanism / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To observe the neurological protective effects of progesterone (PROG) on focal cerebral ischemia/reperfusion injury in rats and to explore its possible mechanism.</p><p><b>METHODS</b>One handred and twenty male SD rats were divided into three groups randomly: sham-operated group, middle cerebral artery occlusion ( MCAO ) group and PROG + MCAO group( n = 40). The right temporary MCAO model was established by the line-embolism method. The PROG + MCAO group rats were according to 8 mg/kg intraperitoneal injection PROG, after that 30 min, the rats were suffered ischemia/reperfusion. After rats were suffered ischemia for 2 h and reperfusion 0, 24, 48, 72 h stress, the nervous functional defect degree were evaluated by longe scoring, and the expression of two-pore domain K channel 3 (TASK3) mRNA in brain tissue were detected by the real-time PCR.</p><p><b>RESULTS</b>PROG (8 mg/kg) could significantly reduced the nervous functional defect degree in rats after ischemia/reperfusion 24, 48, 72 h (P < 0.05). The results of real-time PCR showed that the TASK3 mRNA expression in the brain tissue at all time points significantly decreased in MCAO group compared with sham-operated group (P < 0.05). However, compared with MCAO group, the expression of TASK3 mRNA in brain tissue at all time points dramatically increased in PROG + MCAO group (P < 0.05).</p><p><b>CONCLUSION</b>PROG can improve the nervous functional defect degree after focal cerebral ischemia/reperfusion injury in rats, and the mechanism might be associated with up-regulating the expression of TASK3 mRNA in brain tissue.</p>

Complete genome phylogenetic analysis of five H9N2 avian influenza viruses isolated from poultry flocks in Qinghai lake region / 病毒学报

Five H9N2 avian influenza virus strains were isolated from the environmental samples in live poultry market in Qinghai Lake region from July to September, 2012. To evaluate the phylogenetic characteristics of these H9N2 isolates, the eight gene segments were amplified by RT-PCR and sequenced. The phylogenetic and molecular characteristics of the five strains were analyzed. The results showed that the HA genes of five strains shared 93. 2%-99. 1% nucleotide identities with each other, and the NA genes shared 94. 5%-99. 8% nucleotide identities. The HA cleavage site sequence of the A/environment/qinghai/ 017/2012 isolate was PSKSSRGLF, and the HA cleavage site sequences of the other four strains were all PSRSSRGLF. The HA receptor-binding site had the Q226L mutation. The M1 gene segment had the N30D and T215A mutations. The phylogenetic analysis showed that the five strains were similar to the virus A/chicken/Hunan/5260/2005 (H9N2) isolated in Hunan Province, China and were reassortant genotype viruses; the HA, NA, and NS genes belonged to the Y280-like lineage; the MP gene belonged to the G1-like lineage; the NP, PB1, PB2, and PA genes belonged to the F98-like lineage.

Clinical characteristics and surgical treatment for localized Castleman's disease / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To investigate the clinical characteristics and treatment of localized Castleman's disease (CD), and review the literatures to improve the diagnosis and management of this disease.</p><p><b>METHODS</b>The clinical symptoms, histopathology, CT, MRI findings and results of surgery in 20 patients with localized CD were evaluated retrospectively.</p><p><b>RESULTS</b>The average age of the patients was 37.7 years. The lesions were located in the retroperitoneal space (9 cases), mediastinum (7 cases), pelvic cavity (1 case), neck (1 case), upper arm (1 case), and axillary (1 case). All patients underwent surgical resection, including 9 cases for retroperitoneal resection (6 cases had open operation and 3 cases laparoscopic resection) and 7 cases for mediastinal resection (open operation in 5 cases and thoracoscopic resection in 2 cases). The Castleman's disease was confirmed by histopathology. There were hyaline vascular type of CD in 17 cases, plasma cell type of CD in 1 case, and mixed cellularity type of CD in 2 cases. The duration of follow-up ranged from 12 to 165 months for 16 cases. Among them 15 patients were alive without recurrence, and 1 case had recurrence in the primary site at 47 months after the operation.</p><p><b>CONCLUSIONS</b>Patients with Castleman's disease have no typical clinical symptoms and have normal laboratory results. The majority of patients are of hyaline vascular type of the disease. Imaging examination is helpful to diagnosis, and the final diagnosis depends on pathologic examination. Complete surgical resection of the tumor is the best treatment for localized Castleman's disease.</p>

Effects of taurine on the ultrastructure and P2X7 receptor expression in brain following traumatic brain injury in rats / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To explore the effects of taurine on the ultrastructure and P2X7 receptor protein expression in brain following traumatic brain injury (TBI) in rats.</p><p><b>METHODS</b>Forty male SD rats, were divided randomly into four groups that were sham-operated group, TBI group, TBI plus low-dose taurine group and TBI plus high-dose taurine group. The TBI model was established by Marmarou's method, the expression of P2X7 receptor protein in parietal cortex and hippocampus was detected by the immunohistochemical method, the ultrastructure of parietal cortex were observed by transmission electron microscope.</p><p><b>RESULTS</b>Compared with sham-operated group, the positive expression cells of P2X7 receptor protein in parietal cortex and hippocampus of TBI group were significantly increased (P < 0.01). Compared with TBI group, the positive expression cells of P2X7 receptor protein in parietal cortex and hippocampus of TBI plus low-dose taurine group and TBI plus high-dose taurine group were significantly decreased (P <0.01 or P <0.05). Compared with TBI plus low-dose taurine group, the positive expression cells of P2X7 receptor protein in parietal cortex and hippocampus of TBI plus high-dose taurine group were significantly decreased (P < 0.05 or P < 0.01). The pathological damage of parietal cortex in the TBI plus high-dose taurine group was obviously lightened.</p><p><b>CONCLUSION</b>Taurine exerts the neuroprotective effect on TBI in rats, the protective mechanism might be associated with down-regulating the expression of P2X7 receptor protein in parietal cortex and hippocampus.</p>

Clinical significance of serum NGF level and CD271 expression in patients with acute B lymphoid leukemia / 中国实验血液学杂志

The aim of this study was to detect the nerve growth factor (NGF) level in serum and NGF low affinity acceptor CD271 expression on bone marrow leukemic cells in acute B lymphoid leukemia (B-ALL) patients and to analyze their clinical significance. The NGF level in serum and CD271 expression on leukemic cells in bone marrow were detected by enzyme linked immunosorbent assay and flow cytometry in B-ALL patients respectively. The results indicated that compared with control group, the NGF level in serum of patient group significantly increased (t = 4.191, p < 0.05), but CD271 expression on leukemic cells in bone marrow decreased significantly (t = 4.898, p < 0.05). The complete remission (CR) rate of 25 B-ALL patients was 64% (16/25) after one course of CVAD chemotherapy. There were statistically significant differences of NGF level and CD271 expression in non-remission (NR) group and control group (t = 3.976, p < 0.05 vs t = 5.052, p < 0.05), but there were no statistically difference of NGF level and CD271 expression in CR group (t = 1.102, p > 0.05 vs t = 1.150, p > 0.05) as compared with control group. The CD271 expression before and after chemotherapy between CR and NR groups showed statistically significant differences (t = 3.889, p < 0.05; t = 3.751, p < 0.05 and t = 4.678, p < 0.05 respectively), but NGF level before and after chemotherapy showed no statistical difference between these 2 groups (t = 0.476, p > 0.05). 50% (8/16) patients relapsed during following up, and of their NGF level [(168.00 ± 61.66) pg/ml] and CD271 expression [(52.29 ± 13.00)%] showed the significantly differences, compared with those in control group (t = 5.284, p < 0.05 vs. t = 6.073, p < 0.05), but the NGF level [(81.13 ± 25.32) pg/ml] and CD271 expression [(78.45 ± 7.12)%] of other 8 patients showed no statistical difference as compared with control group (t = 1.228, p > 0.05 vs t = 1.144, p > 0.05). Compared with low NGF level and CD271 low expression groups, the survival time of B-ALL patients with high NGF level and CD271 expression was not changed significantly (p = 0.750 vs p = 0.170). It is concluded that the increased NGF level in serum and decreased CD271 expression on bone marrow leukemic cells in B-ALL patients are related with leukemia development and may be the useful indexes to evaluate curative effect and prognosis.

Construction of lentiviral vector carrying mouse RORγt and expression of RORγt in 293FT cells / 中国实验血液学杂志

This study was aimed to construct a lentiviral vector carrying mouse RORγt and glp gene, and to detect the expression of RORγt in the 293FT cells. The RORγt fragment was amplified by RT-PCR from mouse thymus and cloned into PCR 2.1 vector. The RORγt DNA fragment was prepared by digestion and inserted into MigR1 plasmid, then the RORγt-IRES-GFP was directionally linked with lentiviral transfer plasmid pTK208 to generate a lentiviral vector pXZ9-RORγt. The recombinant lentivirus were produced by co-transfected three plasmids into 293FT packing cells using lipofectamine 2000. After transfection, the lentiviral supernatant was collected and concentrated via ultracentrifugation. The 293FT cells were infected by the concentrated lentivirus, GFP expression was examined under a fluorescent microscope and the expression of RORγt protein was detected by Western blot. The results showed that the RORγt fragment was amplified from cDNA of mouse thymus and recombinant lentiviral vector pXZ9-RORγt was constructed successfully. High titer lentivirus were prepared after one round ultracentrifugation. RORγt expression could be detected in 293FT cells after virus infection. It is concluded that the lentiviral vector pXZ9- RORγt containing mouse RORγt-IRES-GFP is successfully constructed; RORγt can express in 293FT cells via lentiviral vector transduction, which provides an optional tool for further research on the mechanism of RORγt controlling Th17 cell differentiation.

Selective cytotoxic effect of lentivirus-mediated double suicide gene transfer on human gastric adneocarcinoma cells / 南方医科大学学报

<p><b>OBJECTIVE</b>To study the selective cytotoxic effect of lentivirus-mediated double suicide gene (CD/TK) against human gastric carcinoma cells SGC-7901 in vitro.</p><p><b>METHODS</b>SGC-7901 cells were infected with FGW-KDRP-CD/TK vector and the infection efficiency was observed under a fluorescence microscope. The morphological changes of the infected cells were observed by Giemsa staining. Flow cytometry (FCM) was employed for cell cycle analysis, and the expression of CD/TK was detected by RT-PCR. The infected cells were then treated with the prodrugs ganciclovir (GCV) and/or 5-fluorocytosine (5-FC) at different concentrations, and the cytotoxic effects were evaluated using MTT method.</p><p><b>RESULTS</b>The infection efficiency of the lentiviral vector in SGC-7901 cells increased with the titer of the virus, which produced no significant effect on the cancer cell morphology in vitro or on the percentages of G0-G1, G2-M and S phase cells (P>0.05). RT-PCR demonstrated the expression of CD/TK gene in SGC-7901 cells infected by FGW-KDRP-CD/TK. The infected cells were highly sensitive to the prodrugs with a dose-dependent cytotoxic effect within a specific concentration range of the drugs, whereas the non-infected cells were not sensitive to the prodrugs. Combined use of the two prodrugs produced an obviously stronger inhibitory effect than either of the them (P<0.05). When combined, GCV and 5-FC at the concentration of 0.1+40, 1+80, 10+160, and 100+320 mg/L demonstrated a synergetic effect with a CDI<1.</p><p><b>CONCLUSION</b>Lentivirus-mediated CD/TK fusion gene system can selectively kill gastric cancer cells, and the two prodrugs show a synergistic cytotoxic effect.</p>

The role of BRCA1 in DNA damage response

BRCA1 is a well-established tumor suppressor gene, which is frequently mutated in familial breast and ovarian cancers. The gene product of BRCA1 functions in a number of cellular pathways that maintain genomic stability, including DNA damage-induced cell cycle checkpoint activation, DNA damage repair, protein ubiquitination, chromatin remodeling, as well as transcriptional regulation and apoptosis. In this review, we discuss recent advances regarding our understanding of the role of BRCA1 in tumor suppression and DNA damage response, including DNA damage-induced cell cycle checkpoint activation and DNA damage repair.

Effects of calponin-1 gene silencing on the biological behavior of uterine smooth muscle cells / 南方医科大学学报

<p><b>OBJECTIVE</b>To study the effects of calponin-1 expression inhibition on the proliferation , invasiveness, apoptosis and cytoskeleton of uterine smooth muscle cells, and explore the molecular mechanism of calponin-1 in the uterine smooth muscle cells for labor onset.</p><p><b>METHODS</b>siRNA-calponin-1 adenovirus plasmid was constructed and transfected into primarily cultured uterine smooth muscle cells. The proliferation, invasiveness and apoptosis of the cells were determined by MTT assay, matrigel invasion assays and flow cytometry, respectively. Rhodamine-Phalloidin was used for labeling filamentous actin (F-actin), and the morphology and the distribution of F-actin was observed under fluorescence microscopy and analyzed quantitatively.</p><p><b>RESULTS</b>The motor ability of uterine smooth muscle cells decreased significantly after transfection with siRNA-calponin-1 adenovirus plasmid (P<0.05). The transfected cells showed thinner, loosened and irregular F-actin microfibers, and the cells in the empty vector and blank control groups showed thicker and longer F-actin microfibers.</p><p><b>CONCLUSION</b>Inhibition of calponin-1 expression can inhibit uterine smooth muscle cell migration and cause the morphological change and rearrangement of F-actin without affecting its proliferation and apoptosis in vitro, suggesting that the morphological change and rearrangement of F-actin of uterine smooth muscle cell may be one of the important mechanisms in the labor onset.</p>