1. Specific killing effects of double suicide gene system on pancreatic cancer Capan-2 cells
Tumor 2007;27(10):768-771
Objective: To evaluate the specific killing effect of adenovirus (Ad)-mediated double suicide gene system (CD/TK fusion genes) driven by VEGF promoter on pancreatic cancer Capan-2 cells. Methods: VEGF-positive Capan-2 cells were transfected with Ad-VEGFP-CDTK. Ad-free vector acted as negative control. The transfection efficiency was observed and the transcription of CDTK gene was detected by RT-PCR. The Capan-2 cells were treated with 5-fluorocytosine (5-FC) and ganciclovir (GCV) at different concentrations. The effects of the double suicide gene system on cell proliferation and the bystander effects were assessed by MTT assay. Then morphological changes were observed by electronic microscopy and distribution of cell cycle was determined by flow cytometry. Human pancreatic cancer Capan-2 cells were subcutaneously implanted into nude mice. The tumor inhibition rate was calculated. Results: The infection rates of the two resultant recombinant Ads in Capan-2 cells were not significantly different, and they were gradually elevated with the increase in multiple of infection (MOI) of Ads. MTT assay showed that pre-drug dose-dependently inhibited the growth of Capan-2 cells. Apparent bystander effects were also observed. Electronic microscopy demonstrated apoptotic changes of Capan-2 cells. Typical apoptotic peak was detected in double suicide gene system-treated group by flow cytometry. Cell cycle distribution analysis showed that the proportion of G0/G1 increased and the number of cells in G2/M and S phase decreased after treatment. The implanted tumor model was successfully established in nude mice. The tumor size was decreased significantly after treatment with double suicide gene system. Conclusion: The promoter of VEGF regulated double suicide gene system can specifically kill pancreatic cancer Capan-2 cells and induce apoptosis in vitro. And it significantly inhibites the growth of implanted pancreatic tumor in nude mice.
2.Experimental studies on apoptosis of human hepatocellular carcinoma cell induced by VEGFP-CDglyTK system
Heng KONG ; Zonghai HUANG ; Jinlong YU
Medical Journal of Chinese People's Liberation Army 1981;0(06):-
Objective To study the effects of suicide gene system mediated by adenovirus containing the CD-TK fusion gene controlled by human vascular endothelial growth factor(VEGF)promoter on apoptosis of human hepatocellular carcinoma cells HepG2 in vitro.Methods The VEGF-expressing HepG2 cells were infected by adenovirus vector containing CD-TK fusion gene controlled by the VEGF promoter(Ad-VEGFP-CDglyTK).The infection efficiencies in HepG2 cells were observed under a fluorescence microscope.The toxic effect of 5-fluorocytosine(5-FC)and ganciclovic(GCV)on infected cells was determined by light microscopy,electron-microscopy and flow cytometry(FCM).Results The transfection efficiency in HepG2 cells increased with the increasing adenoviral titer.The pro-drug(5-FC and GCV)could induce apoptosis of HepG2 cells in certain range of dosage(the doses of GCV+5-FC:1mg/L + 20mg/L,10mg/L + 40mg/L,100mg/L + 60mg/L)at the multiplicity of infection(MOI)of 100.The effect showed a time-dependent manner.HepG2 cells showed typical morphologic changes of apoptosis after administration of the pro-drug(GCV:10mg/L,5-FC:40mg/L)for 72 hours:chromatin condensation and disposition along nuclear membrane.Karyopyknosis and karyoklasis were seen under electron microscopy(?10 000).Apoptotic peak was also shown in HepG2 cells treated with the pro-drug(5-FC and GCV)by flow cytometry.The cell apoptosis rate was increased accordingly as the concentration of pro-drug(5-FC and GCV)increased.The apoptosis was increased obviously in comparison with the negative control group(P
3.Adenovirus mediated fusion gene system driven by VEGF promoter kills pancreatic cancer cell
Zonghai HUANG ; Heng KONG ; Zhenyu YAN ; Xu CHEN
Chinese Journal of General Surgery 2008;23(3):219-222
Objective To evaluate the selectively killing effect of adenovirus(Ad)mediated double suicide gene driven by VEGF promoter on pancreatic cancer cell SW1990. Methods VEGFexpressing SW1990 were infected by Ad-VEGFP-CDTK and Ad-null.respectively.The infection rate was observed and the expression of CDTK was detected by RT-PCR and Western blotting.Followed by treatment with 5-FC and GCV killing effects were evaluated and bystander effects were analyzed by MTF.Pathological character of cells was observed by electron microscopy and distribution of cell cycle was detected by flow cytometry.The caspase-3 activity was detected by absorption spectrometry. Results The infection rate of the resultant recombinant Ad to SW1990 cells was not apparently different.RT-PCR and Western blotting demonstrated product of CDTK gene in SW1990 cell infected by Ad-VEGFP-CDTK.Prodrug could inhibit proliferation of SW1990 and the effect was dose-dependent.There was considerable bystander effect as observed by MTF.Apoptotic peak was also shown by flow cytometry.Morphologic features of apoptosis in SW1990 cells were displayed via electron microscopy.Cells at the G0-G1 phase was increasing and the rate at the G2-M and S phase was decreased by prodrug.The caspase-3 activity gradually rised with the increasing concentration of the prodrug. Conclusions The CDTK fusion gene system controlled by VEGF promoter has killing effect on the VEGF-expressing SW1990 cells and inducing the cell apoptosis.
4.Research advancement of tissue engineering in urology
Heng SUN ; Zhankui ZHAO ; Lin MENG ; Honglian YU ; Qingsheng KONG
Chinese Journal of Tissue Engineering Research 2017;21(8):1306-1312
BACKGROUND: Tissue engineering provides a new way for the repair of urinary tissue and organ defects.Urinary tissue engineering has shown a bright prospect.OBJECTIVE: To review the latest research on urinary tissue engineering at national and international level.METHODS: With the keywords of tissue engineering, urology, scaffold, vascularization in Chinese and in English,respectively, a computer-based search for articles published from January 2000 to January 2016 was performed in CNKI and PubMed databases. The articles addressing urology tissue engineering, scaffolds and vascularization were collected,summarized and analyzed.RESULTS AND CONCLUSION: The selection and cultivation of seed cells, scaffold material performance, tissue construction in vitro, and degree of vascularization all make an important influence on the repair of urinary injuries. As different seed cells hold different biological characteristics, we should make full consideration prior to choosing an appropriate seed cell, so as to pave a good foundation for urinary tissue engineering. Scaffolds with good three-dimensional structure can promote the cell growth and proliferation, tissue in-growth and vascularization.Tissue-engineered materials are superior to traditional repair materials, but still on initial stage, and further large scale trials will be necessary. Moreover, some problems needed to be solved, such as the regenerated tissue with incomplete function different from natural tissues, and regeneration failure caused by biological stent rejection.
5.Fusarium species Associated with Fruit Rot of Banana (Musa spp.), Papaya (Carica papaya) and Guava (Psidium guajava)
Latiffah Zakaria ; Mazzura Wan Chik ; Kong Wai Heng ; Baharuddin Salleh
Malaysian Journal of Microbiology 2012;8(2):127-130
A total of 60 isolates of Fusarium were isolated from fruit rot of banana (Musa spp.), papaya (Carica papaya) and guava (Psidium guajava). The most common species recovered from the fruit rot of the three fruit crops were F. semitectum (40 %), F. solani (38.3 %), F. verticillioides (11.7 %) and F. oxysporum (10 %). Fusarium semitectum was isolated from fruit rot of banana, papaya and guava; F. oxysporum from banana and papaya; F. solani from banana and guava and F. verticillioides from banana. From pathogenicity tests, F. solani and F. semitectum were pathogenic to both banana and papaya and F. verticillioides to banana. F. oxysporum was not pathogenic to banana and papaya and F. semitectum was not pathogenic to guava. The results of the present study showed the presence of several Fusarium spp. on fruit
rot of banana, papaya and guava and several species are found to be pathogenic causing fruit rot on their hosts.
6.Comparative study on endoscopic thyroidectomy versus conventional thyroidectomy in thyroid disease
Heng KONG ; Linyu TAO ; Ke QI ; Duo FENG ; Wenjun WEI ; Qiusheng LIN
Chinese Journal of Primary Medicine and Pharmacy 2012;19(16):2419-2420
ObjectiveThe aim of this study was to evaluate and compare the surgical outcomes of endoscop ic and conventional open thyroidectomies in patients with thyroid disease.Methods116 patients with tyroid tumor were enrolled.56 patients underwent endoscopic thyroidectomy ( endoscopic group ),and 60 patients underwent conventional open thyroidectomy( conventional group).We analyzed the patients' clinic characteristics,surgical outcomes and complications between the two groups.ResultsThe blood loss was less in the endoscopic group than the open group[( 16.8 ± 9.6) ml vs ( 24.9 ± 14.2 ) ml,t =- 2.427,P < 0.05].The degree of satisfaction for cosmetic outcome in endoscopy group( 96.4% ) was higher than that in conventional group ( 16.7% ) ( x2 =74.508,P < 0.01 ).There was no significant difference in the operating time,volume of drainage and postoperative hospital stay between two groups,and there was no significant difference in the skin ecchymosis,redness and swelling and postoperative pain between two groups( all P > 0.05).No severe postoperative complication was encountered,such as injuries of the re current or superior laryngeal nerve,parathyroid gland injury or massive hemorrhage.ConclusionEndoscopic thyroidectomy has less blood loss,mini-open and excellent cosmetic benefits compared with conventional open thyroidectomy.
7.Targeting therapy for colorectal cancer with double suicide genes driven by VEGF promoter
Xinjun HAN ; Zonghai HUANG ; Jinlong YU ; Zhou LI ; Heng KONG ; Qiang LI
Chinese Journal of General Surgery 2010;25(1):48-52
Objective To investigate the curative effect of an adenovirus-mediated fusion gene system driven by VEGF promoter (AdVEGF-CDglyTK) on a nude mouse model of colorectal cancer and analyze the mechanism underlying its therapeutic effect.Methods The animal model of the colorectal cancer was established by using transplantation of the cultivated cells,human colorectal cell line LoVo,via subcutaneous injection on the back of nude mice.Twenty nude mice were equally divided into four groups:group Ⅰ received injection of AdVEGF-CDgiyTK plus 5-flurocytosine/ganciclovir(5-FC/GCV);group Ⅱwere given 5-FC/GCV;group Ⅲ were with AdVEGF-CDglyTK;group Ⅳ were used as control.Results CDglyTK was expressed exclusively in the tumor tissues from the group Ⅰ and Ⅲ by RT-PCR.The phenotype and pathological analysis showed that tumor growth was dramatically inhibited in group Ⅰwhen compared with other three groups,while no significant difference was found between group Ⅱ,group Ⅲ and group Ⅳ.The TUNEL assay demonstrated that the apoptosis rate of 38.65% ± 4.20 significantly increased in group Ⅰ when compared with other three groups (F = 397.530,P =0.000).The tumor microvessel density of 3.08±0.79 decreased significantly in group Ⅰ (F = 34.081,P = 0.000) when compared with other three groups.Conclusion The results suggested that AdVEGF-CDglyTK with 5-FC/GCV can inhibit the tumor growth of colorectal cancer significantly in vivo by a mechanism of systeminduced apoptosis and the efficient suppression of angiogenesis.
8.Isolation, identification and functional characteristics of murine B10 cells
Yao QIN ; Mei ZHANG ; Ruimei JIANG ; Lulu KONG ; Xinyu XU ; Heng CHEN ; Tao YANG
Chinese Journal of Microbiology and Immunology 2013;(11):819-827
Objective To investigate the phenotypes and percentages of B 10 cells in different tis-sues from wild-type mice and to identify their biological functions .Methods The percentages of B10 cells derived from different tissues of mice and their responses to lipopolysaccharide ( LPS) stimulation were ana-lyzed by flow cytometry .Magnetic-activated cell sorting ( MACS ) and fluorescence-activated cell sorting (FACS) were used to purify B10 cells, CD4+CD25-T cells and Treg cells.CD4+CD25-T cells and Treg cells labeled by CFSE were co-cultured with or without B10 cells, and then their proliferation were evaluated after 72 h.Results (1) A subset of CD19+CD5+CD1dhigh regulatory B cells was identified in spleen , pe-ripheral blood and lymph nodes from wild-type mice , of which the highest frequency was detected in spleen (3.95%±0.79%, P<0.05).The isolated B cells from different tissues were stimulated by LPS , PMA, ionomycin and monensin (L+PIM) in vitro to express IL-10.Among them, splenic CD19+IL-10+B cells showed the highest expression of IL-10 (P<0.05).(2) Prolonged LPS stimulation (48 h) to CD5+CD1dhigh B cells enhanced the expressions of IL-10 (P<0.01).(3) CD19+CD5+CD1dhigh B cells inhibited the prolif-eration of CD4+CD25-T cells in vitro in a dose-dependent manner (P<0.01), but increased the secretion of IL-10 by CD4+T cells (P<0.01) and the proliferation of Treg cells in vitro (P<0.01).Conclusion Com-pared with other tissues , the percentage of B10 cell subset in spleen is the highest in wild-type mouse , and B10 cells subset can be activated through Toll-like receptor ( TLR ) signaling pathway .The responses of CD4+CD25-T cells and Treg cells in co-culture with B10 cells are regulated by B 10 cell subset through an increased IL-10 production .B10 cells might be a useful cell population for the treatment of inflammatory au-toimmune diseases.
9.Aetiology of viral central nervous system infection, a Malaysian study
Yean Kong Yong ; Heng Thay Chong ; Kum Thong Wong ; Chong Tin Tan ; Shamala Devi
Neurology Asia 2008;13(1):65-71
Over 100 viruses are known to cause acute viral encephalitis in human. In order to diagnose a viral
central nervous system infection, various laboratory diagnosis methods have been used. In this study,
we examined 220 cerebrospinal fluid samples that were received at the Diagnostic Virology Laboratory
of University Malaya Medical Centre between year 2004 to 2006, by viral isolation, pathogen specific
antibody ELISA, polymerase chain reaction (PCR) and Real-Time PCR. Majority of the samples
were from patients <10 years old. Out of 220 samples, 3 were positive for viral isolation, 27 for
PCR (inclusive for the 3 positive for viral isolation) and 39 for pathogen specific ELISA. The total
positive detection rate of this study was 30%. Herpes virus was the most important aetiologic agent,
responsible for 58% of infection, followed by paramyxovirus (especially measles virus) in 26% of
infection, and 14% by enterovirus. Parvovirus and flavivirus were the other common viruses. Among
the herpes viruses, herpes simplex and cytomegalovirus were the most common.
10.Validation of a Risk Score Incorporating Tumor Characteristics into the American Joint Committee on Cancer Anatomic Stage for Breast Cancer
Yi Heng SEOW ; Ru Xin WONG ; John Heng Chi LIM ; Weixiang LIAN ; Yoon Sim YAP ; Fuh Yong WONG
Journal of Breast Cancer 2019;22(2):260-273
PURPOSE: The American Joint Committee on Cancer 8th edition (AJCC8) prognostic stage (PS) was implemented January 1, 2018, but it is complex due to multiple permutations. A North American group proposed a simpler system using the anatomic stage with a risk score system (RSS) of 1 point each for grade 3 tumor and human epithelial growth factor receptor 2 (HER2) and estrogen receptor (ER) negativity. Here we aimed to evaluate this risk score system with our database of Asian breast cancer patients and compare it against the AJCC8 PS. METHODS: Patients diagnosed with breast cancer stage I–IV in 2006–2012 were identified in the SingHealth Joint Breast Cancer Registry. Five-year breast cancer-specific survival (CSS) and overall survival (OS) were calculated for each anatomic stage according to the risk score and compared with the AJCC8 PS. RESULTS: A total of 6,656 patients were analyzed. The median follow-up was 61 (interquartile range, 37–90) months. There was a high receipt of endocrine therapy (84.6% of ER+ patients), chemotherapy (84.3% of node-positive patients), and trastuzumab (86.0% of HER2+ patients). Within each anatomic stage, there were significant differences in survival in all sub-stages except IIIB. On multivariate analysis, the hazard ratio for negative ER was 1.74 (1.48–2.06), for negative HER2 was 1.49 (1.26–1.74), and for grade 3 was 1.84 (1.55–2.19). On multivariate analysis controlled for age, ethnicity, and receipt of chemotherapy, the RSS (Akaike information criterion [AIC] = 10,649.45; Harrell's Concordance Index [C] = 0.85) was not inferior to the AJCC8 PS (AIC = 10,726.65; C = 0.84) for CSS, nor was the RSS (AIC = 14,714.4; C = 0.82) inferior to the AJCC8 PS (AIC = 14,784.69; C = 0.81) for OS. CONCLUSION: The RSS is comparable to the AJCC8 PS for a patient population receiving chemotherapy as well as endocrine- and HER2-targeted therapy and further stratifies stage IV patients.
Asian Continental Ancestry Group
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Biomarkers
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Breast Neoplasms
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Breast
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Drug Therapy
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Estrogens
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Follow-Up Studies
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Humans
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Joints
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Multivariate Analysis
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Trastuzumab