Biomedical subjects

H Hui

Publications and source records attributed to H Hui.

At least 19 recordsLinked to original sources

PubMed2002

Cultured pancreatic ductal cells undergo cell cycle re-distribution and beta-cell-like differentiation in response to glucagon-like peptide-1.

The intestinal hormone glucagon-like peptide-1 (GLP-1) has been shown to promote an increase in pancreatic beta-cell mass via proliferation of islet cells and differentiation of non-insulin-secreting cells. In this study, we have characterized some of the events that lead to the differentiation of pancreatic ductal cells in response to treatment with human GLP-1. Rat pancreatic ductal (ARIP) cells were cultured in the presence of GLP-1 and analyzed for cell counting, cell cycle distribution, expression of cyclin-dependent-kinase (Cdk) inhibitors, transcription of beta-cell-specific genes, loss of ductal-like phenotype and acquisition of beta-cell-like gene expression profile. Exposure of ARIP cells to 10 nM GLP-1 induced a significant reduction in the cell replication rate and a significant decrease in the percentage of cells in S phase of the cell cycle. This was associated with an increase in the number of cells in G0-G1 phase and a reduction of cells in G2-M phase. Western blot analysis for the Cdk inhibitors, kinase inhibitor protein 1 (p27(Kip1)) and Cdk-interacting protein 1 (p21(Cip1)), demonstrated a significant increase in p27(Kip1) and p21(Cip1) levels within the first 24 h from the beginning of GLP-1 treatment. As cells slowed down their proliferation rate, GLP-1 also induced a time-dependent expression of various beta-cell-specific mRNAs. The glucose transporter GLUT-2 was the first of those factors to be expressed (24 h treatment), followed by insulin (44 h) and finally by the enzyme glucokinase (56 h). In addition, immunocytochemistry analysis showed that GLP-1 induced a time-dependent down-regulation of the ductal marker cytokeratin-20 (CK-20) and a time-dependent induction of insulin expression. Finally, GLP-1 promoted a glucose-dependent secretion of insulin, as demonstrated by HPLC and RIA analyses of the cell culture medium. The present study has demonstrated that GLP-1 induces a cell cycle re-distribution with a decrease in cell proliferation rate prior to promoting the differentiation of cells towards an endocrine-like phenotype.

Animals↗

PubMed2001

Molecular characterization of a highly divergent HIV type 1 isolate obtained early in the AIDS epidemic from the Democratic Republic of Congo.

Numerous complete human immunodeficiency virus type 1 (HIV-1) genomes have been characterized for contemporary viruses, but few isolates obtained early in the HIV-1 epidemic have been studied. In this article, we describe the molecular characterization of an HIV-1 isolate (83CD003) that was obtained from an AIDS patient in Kinshasa, Democratic Republic of Congo (DRC) in 1983. The complete 83CD003 genome was sequenced in its entirety and found to encode uninterrupted open reading frames for all viral genes. Phylogenetic analysis revealed 83CD003 was a member of the major (M) group of HIV -1, but did not group with any of the known subtypes. Rather, it formed an independent lineage in all regions of its genome that was roughly equidistant from representatives of all other subtypes. Similarly, 83CD003 also did not cluster with any of several unclassified group M sequences that have been reported more recently to circulate in the DRC, suggesting that it may represent an early group M lineage thai is either rare or has gone extinct. The molecular clone of 83CD003 yielded an infectious virus after transfection into mammalian cells and its biological properties can be further studied.

Cell Line↗

PubMed2001

Engineering inhibitors highly selective for the S1 sites of Ser190 trypsin-like serine protease drug targets.

BACKGROUND: Involved or implicated in a wide spectrum of diseases, trypsin-like serine proteases comprise well studied drug targets and anti-targets that can be subdivided into two major classes. In one class there is a serine at position 190 at the S1 site, as in urokinase type plasminogen activator (urokinase or uPA) and factor VIIa, and in the other there is an alanine at 190, as in tissue type plasminogen activator (tPA) and factor Xa. A hydrogen bond unique to Ser190 protease-arylamidine complexes between O gamma(Ser190) and the inhibitor amidine confers an intrinsic preference for such inhibitors toward Ser190 proteases over Ala190 counterparts. RESULTS: Based on the structural differences between the S1 sites of Ser190 and Ala190 protease-arylamidine complexes, we amplified the selectivity of amidine inhibitors toward uPA and against tPA, by factors as high as 220-fold, by incorporating a halo group ortho to the amidine of a lead inhibitor scaffold. Comparison of K(i) values of such halo-substituted and parent inhibitors toward a panel of Ser190 and Ala190 proteases demonstrates pronounced selectivity of the halo analogs for Ser190 proteases over Ala190 counterparts. Crystal structures of Ser190 proteases, uPA and trypsin, and of an Ala190 counterpart, thrombin, bound by a set of ortho (halo, amidino) aryl inhibitors and of non-halo parents reveal the structural basis of the exquisite selectivity and validate the design principle. CONCLUSIONS: Remarkable selectivity enhancements of exceptionally small inhibitors are achieved toward the uPA target over the highly similar tPA anti-target through a single atom substitution on an otherwise relatively non-selective scaffold. Overall selectivities for uPA over tPA as high as 980-fold at physiological pH were realized. The increase in selectivity results from the displacement of a single bound water molecule common to the S1 site of both the uPA target and the tPA anti-target because of the ensuing deficit in hydrogen bonding of the arylamidine inhibitor when bound in the Ala190 protease anti-target.

Animals↗

PubMed2001

Reversion of the malignant phenotype of gastric cancer cell SGC7901 by c-erbB-2-specific hammerhead ribozyme.

The c-erbB-2/neu-encoded protein p185 is closely related to the growth and metastasis of adenocarcinoma. We sought to reverse the malignant phenotype of gastric cancer cell line SGC7901 with c-erbB-2-specific ribozyme. We designed the ribozyme and generated the in vitro transcription vectors of the ribozyme and its substrate. In vitro cleavage reaction indicated that the ribozyme catalyzed 79.3% target RNA in 1 hour at 37 degrees C. Then, we generated the eucaryotic expression vectors of the ribozyme and transfected them into SGC7901 cells, which highly express p185. Analyses showed that the c-erbB-2 mRNA and p185 were reduced remarkably in the ribozyme-transfected cells. The growth rate of the ribozyme-transfected cells was much lower than that of the control group. Tumorigenicity was also decreased dramatically in nude mice. The results demonstrated that c-erbB-2-specific ribozyme may inhibit the malignancy of gastric cancer cells SGC7901.

Adenocarcinoma↗

PubMed2001

Pancreatic beta-cells expressing the Arg64 variant of the beta(3)-adrenergic receptor exhibit abnormal insulin secretory activity.

The Arg64 beta(3)-adrenergic receptor (beta(3)AR) variant is associated with an earlier age of onset of diabetes and lower levels of insulin secretion in humans. The aims of this study were to investigate whether beta(3)AR is expressed by islet cells, if receptor binding affects insulin secretion and, finally, if the beta(3)AR Arg64 variant induces abnormal insulin secretory activity. Human pancreas extracts were subjected to RT-PCR, Western blotting and immunostaining analyses. DNA sequencing and Western blotting demonstrated that the beta(3)AR gene is transcribed and translated in the human pancreas; immunostaining showed that it is expressed by the islets of Langerhans. Cultured rat beta-cells responded to human beta(3)AR agonists in a dose- and time-dependent manner. Transfection of cultured rat beta-cells with the wild-type human beta(3)AR produced an increased baseline and ligand-dependent insulin secretion compared with parental cells. On the other hand, cells transfected with the Arg64 variant of the beta(3)AR secreted less insulin, both spontaneously and after exposure to human beta(3)AR agonists. Furthermore, while transfection with the wild-type beta(3)AR preserved the glucose-dependent secretion of insulin, expression of the variant receptor rendered the host cells significantly less responsive to glucose. In summary, cells express the beta(3)AR, and its activation contributes to the regulation of insulin secretion. These findings may help explain the low levels of insulin secretion in response to an i.v. glucose tolerance test observed in humans carrying the Arg64 polymorphism.

Adrenergic beta-3 Receptor Agonists↗

PubMed2001

Glucagon-like peptide 1 induces differentiation of islet duodenal homeobox-1-positive pancreatic ductal cells into insulin-secreting cells.

Glucagon-like peptide-1 (GLP-1) is an incretin hormone capable of restoring normal glucose tolerance in aging glucose-intolerant Wistar rats. Whether the antidiabetic properties of GLP-1 are exclusively due to its insulin secretory activity remains to be determined. A GLP-1-dependent differentiation of pancreatic precursor cells into mature beta-cells has recently been proposed. The aim of this study was to investigate whether pancreatic ductal epithelial cells could be differentiated into insulin-secreting cells by exposing them to GLP-1. Rat (ARIP) and human (PANC-1) cell lines, both derived from the pancreatic ductal epithelium, were used to test this hypothesis. A major difference distinguishes these two cell lines: whereas ARIP cells spontaneously express the beta-cell differentiation factor islet duodenal homeobox-1 (IDX-1), PANC-1 cells are characteristically IDX-1 negative. GLP-1 induced the differentiation of ARIP cells into insulin-synthesizing cells, although it did not affect the phenotype of PANC-1 cells, as determined by fluorescence-activated cell sorting (FACS) analysis. Differentiation of ARIP cells by exposure to human GLP-1 occurs in a time- and dose-dependent manner, and this is associated with an increase in IDX-1 and insulin mRNA levels. Secretion of insulin was also induced in a parallel manner, and it was regulated by the concentration of glucose in the culture medium. Interestingly, PANC-1 cells, when stably transfected with human IDX-1, gained responsiveness to GLP-1 and were able to differentiate into beta-cells, as determined by FACS analysis, insulin gene expression, intracellular insulin content, and insulin accumulation in the culture medium. Finally, we demonstrated that the receptor for GLP-1 is constitutively expressed by ARIP and PANC-1 cells and that the mRNA level for this transcript was increased by cellular transfection with human IDX-1. In summary, our study provides evidence that GLP-1 is a differentiation factor for pancreatic ductal cells and that its effect requires the expression of IDX-1.

Actins↗

PubMed2001

Urinary excretion of aquaporin-2 water channel protein in chronic heart failure rats.

OBJECTIVE: To study the urinary excretion of aquaporin-2 (AQP2) water channel protein, and the relationship between urine AQP2 concentration and renal AQP2 gene expression in chronic heart failure (CHF) rats. METHODS: Male Sprague-Dawley rats (200 g-250 g) underwent either a left coronary artery ligation, a model of CHF, or a sham-operation. Nine weeks after surgery, urinary AQP2 concentrations and renal AQP2 protein levels were measured by Western blot. RESULTS: The urinary concentration of AQP2 water channel protein increased significantly in CHF rats as compared with sham-operated rats (365.6% +/- 102.9% vs 98.5% +/- 47.6%, P < 0.01). There was positive correlation between urinary AQP2 concentration and renal AQP2 protein expression (r = 0.89, P < 0.01). CONCLUSION: The urinary concentration of AQP2 water channel protein increases significantly in chronic heart failure rats.

Animals↗

PubMed2000

Inhibition of cell proliferation in HCC-9204 hepatoma cells by a c-myc specific ribozyme.

A ribozyme (RZ) gene targeting c-myc mRNA was synthesized and cloned. Cleavage reaction showed that cleavage of the RZ was efficient and specific. The RZ gene-containing retrovirus vector pDOR-RZ was transfected into HCC-9204 hepatoma cells, which constitutively express high levels of c-myc using Lipofectamine. Positively transfected cells were selected using G418. In situ hybridization showed that both pDOR-RZ and pDOR vectors had been integrated into the chromosome of HCC-9204 cells. Dot blot hybridization indicated that expression of the RZ was only evident in pDOR-RZ-transfected HCC-9204 cells. Avidin-biotin complex enzyme-linked immunosorbent assay showed that c-myc expression was down-regulated. Chromatin aggregation into compact masses, cytoplasmic vacuole degeneration, and blurring of cytoplasm structure were observed by transmission electron microscopy in HCC-9204-RZ cells. These results suggest that the use of a c-myc mRNA cleaving enzyme could be most effective in tumor cells that are highly proliferative and constitutively express high levels of c-myc.

Carcinoma, Hepatocellular↗

PubMed2000

Multislice helical CT: image temporal resolution.

A multislice helical computed tomography (CT) halfscan (HS) reconstruction algorithm is proposed for cardiac applications. The imaging performances (in terms of the temporal resolution, z-axis resolution, image noise, and image artifacts) of the HS algorithm are compared to the existing algorithms using theoretical models and clinical data. A theoretical model of the temporal resolution performance (in terms of the temporal sensitivity profile) is established for helical CT, in general, i.e., for any number of detector rows and any reconstruction algorithm used. It is concluded that the HS reconstruction results in improved image temporal resolution than the corresponding 180 degrees LI (linear interpolation) reconstruction and is more immune to the inconsistent data problem induced by cardiac motions. The temporal resolution of multislice helical CT with the HS algorithm is comparable to that of single-slice helical CT with the HS algorithm. In practice, the 180 degrees LI and HS-LI algorithms can be used in parallel to generate two image sets from the same scan acquisition, one (180 degrees LI) for improved z-resolution and noises, and the other (HS-LI) for improved image temporal resolution.

Algorithms↗

PubMed1999

Evaluation of a mathematical model to predict intrapulmonary shunt non-invasively.

PURPOSE: We have previously published a mathematical model of oxygen transport. Using several physiological assumptions, the model provides a non-invasive estimate of intrapulmonary shunt. During a larger study of lung injury in a pig model, we had the opportunity to check the validity of our assumptions and the accuracy of the model's predictions. METHODS: We used six female pigs, average weight 12.8 kg. Following general anesthesia, tracheostomy and insertion of pulmonary venous and arterial lines, lung injury was induced by repeated saline lung lavage. Using hemodynamic measurements made at different levels of inspired oxygen, intrapulmonary shunt was calculated both by the traditional shunt equation and also by our mathematical model based on non-invasive measurements of FIO2 and SaO2. RESULTS: There was good agreement between the two methods of shunt calculation. Using linear regression the correlation coefficient was 0.95. Bland and Altman analysis showed a bias of -0.8 and precision of 12%. CONCLUSION: In a controlled setting, intrapulmonary shunt can be estimated from non-invasive measurements to a reasonable degree of accuracy. However, the calculation requires too many assumptions to be of general clinical value. The equations used provide a validated physiological model that acts as a useful tool for teaching cardiorespiratory physiology.

Animals↗

PubMed1999

[Effects of retrovirus-mediated HSV-tk/GCV on human hepatocellular carcinoma].

OBJECTIVE: The efficacy of the herpes simplex virus thymidine kinase/ganciclovir (HSV-tk/GCV) suicide-gene therapy system on human hepatocellular carcinoma was observed in vitro as well as ex vivo. METHODS: The recombinant retroviral vector containing HSV-tk gene was constructed and HCC9204 human hepatocellular carcinoma cell line was infected with the recombinant retrovirus. Following selection the HCC9204/tk cell line which stably expressed tk was cloned. The sensitivity of HCC9204/tk cells to GCV was examined in vitro. Antitumor effects of GCV were also observed after the administration of GCV in nude mice bearing tumor derived from HCC9204/tk cells. RESULTS: The HSV-tk gene expressed stably in HCC9204/tk cells. In vitro the growth inhibition studies showed that HCC9204/tk cells were highly sensitive to GCV (IC50 1.2 mg/L in 72 hour), and the HSV-tk gene-modified HCC9204/tk cells were toxic to nearby unmodified HCC9204 tumor cells that were resistant to GCV. This phenomenon was termed "bystander effect". Ex vivo studies showed similar results that significant tumor inhibition was found in the treatment group than in control group. CONCLUSION: Tumor cells expressing HSV-tk gene can be eradicated by GCV in vitro and ex vivo. The HSV-tk/GCV suicide-gene therapy system mediated retrovirally may provide an effective approach to treatment of human hepatoma.

Animals↗

PubMed1999

[Reversion of the malignant phenotype of gastric cancer by c-erbB-2 specific ribozyme].

OBJECTIVE: To probe the effect of c-erbB-2 specific ribozyme to the malignant phenotype of gastric cancer. METHODS: The eucaryotic expression vector of c-erbB-2 specific ribozyme RZ1 was designed by computer and named pDOR-RZ1. The transfection of the gastric cancer cell line SGC-7901 was mediated by Lipofect AMINE. Flow cytometry was used to analyse the expression of the c-erbB-2 product P185. In vivo study of tumorogenecity of the transfected cells was performed in nude mice. RESULTS: pDOR-RZ1 was successfully transfected into the gastric cancer cell line SGC-7901 and then the single clones were selected by G418 and named SGC/RZ1. Flow cytometry analysis showed that the expression of P185 was suppressed by 62.7%. The growth rate of SGC/RZ1 was inhibited by 55%. The tumor-forming time in SGC/RZ1 in nude mice was delayed remarkably and the tumor size was also much smaller than that in the control group, indicating the inhibition of the tumorogenecity of SGC/RZ1 in nude mice. CONCLUSION: c-erbB-2 specific ribozyme is very efficient in reversing the malignant phenotype of gastric cancer. This might provide a new approach for gene therapy of gastric cancer.

Animals↗

PubMed1999

[Transfection of articular chondrocytes with PcNDA3-hBMP3 and its stable expression].

OBJECTIVE: To explore the possibility of stable expression of PcDNA3-hBMP3 in cultured articular chondrocytes of rabbit. METHODS: PcDNA3-hBMP3 was constructed using gene clone technique and recombined DNA technique. With the help of profectamine, the cultured articular chondrocytes were transfected with PcDNA3-hBMP3, and the evidence of successfully stable transfection in these cells could be obtained by positive northern blot. RESULTS: The cultured articular chondrocytes of rabbits seemed to be polygonal, and its logarithmic growth phase was 2 - 4 days after cell inoculation. The two fragments cut from PcDNA3-hBMP3 by EcoR I and Xba I represented 5.4 kb and 1.4 kb by electrophoresis, which were confirmed to be the carrier and the fragment inserted originally, indicating that the construction of PcDNA3-hBMP3 was successful. The RNA extracted from cultured chondrocytes was screened for 4 weeks by G418 hibrided with the fragment cut from hBMP3 positively. CONCLUSIONS: With the help of profectamine, the cultured articular chondrocytes can be transfected by recombined gene of PcDNA3-hBMP3 successfully, and their stable expression at 4 weeks after transfection is obtained.

Animals↗

PubMed1998

[Construction of PCNA antisense RNA expression vector and its antitumorigenic effect on human gastric cancer cell].

OBJECTIVE: To observe the effect of proliferating cell nuclear antigen (PCNA) antisense RNA on the growth characteristics of human gastric cancer cell. METHODS: An eukaryotic expression vector pDR-PCNA with human PCNA gene insert in reverse direction was successfully constructed. The human gastric cancer cell line SGC-7901 was transfected with pDR-PCNA by lipofectamine. RESULTS: Growth rate, protein and RNA biosynthesis and DNA contents in S-phase and G2/M-phase of the transfected SGC-7901 were significantly suppressed in comparison with those of the parental cell line. CONCLUSION: PCNA antisense RNA can significantly suppress the in vitro growth of gastric cancer cell line.

Cell Division↗

PubMed1997

Complementation of integrase function in HIV-1 virions.

Proviral integration is essential for HIV-1 replication and represents an important potential target for antiviral drug design. Although much is known about the integration process from studies of purified integrase (IN) protein and synthetic target DNA, provirus formation in virally infected cells remains incompletely understood since reconstituted in vitro assays do not fully reproduce in vivo integration events. We have developed a novel experimental system in which IN-mutant HIV-1 molecular clones are complemented in trans by Vpr-IN fusion proteins, thereby enabling the study of IN function in replicating viruses. Using this approach we found that (i) Vpr-linked IN is efficiently packaged into virions independent of the Gag-Pol polyprotein, (ii) fusion proteins containing a natural RT/IN processing site are cleaved by the viral protease and (iii) only the cleaved IN protein complements IN-defective HIV-1 efficiently. Vpr-mediated packaging restored IN function to a wide variety of IN-deficient HIV-1 strains including zinc finger, catalytic core and C-terminal domain mutants as well as viruses from which IN was completely deleted. Furthermore, trans complemented IN protein mediated a bona fide integration reaction, as demonstrated by the precise processing of proviral ends (5'-TG...CA-3') and the generation of an HIV-1-specific (5 bp) duplication of adjoining host sequences. Intragenic complementation between IN mutants defective in different protein domains was also observed, thereby providing the first evidence for IN multimerization in vivo.

Amino Acid Sequence↗

PubMed1997

A full-length and replication-competent proviral clone of SIVAGM from tantalus monkeys.

African green monkeys (AGM) are classified into four distinct species (commonly termed vervet, grivet, sabaeus, and tantalus monkeys), all of which are known to be infected with simian immunodeficiency virus (SIVAGM) in the wild. Sequence analysis of partial gag and env regions has indicated that each of the four species harbors a phylogenetically distinct SIVAGM subtype. This species-specific diversity suggests that African green monkeys have been infected with SIVAGM for an extended period of time, possibly even before their speciation from a common ancestor. However, our understanding of the evolutionary history of this group of viruses is still incomplete, in part because sequence information for most isolates is limited to small subgenomic regions. There are only six SIVAGM proviruses which have been sequenced in their entirety, and these represent only three of the four SIVAGM lineages (i.e., SIVAGMgri, SIVAGMver, and SIVAGMsab). In this paper, we have generated the first full-length proviral clone for SIVAGM infecting tantalus monkeys (SIVAGMtan). Lambda phage techniques were employed to clone this provirus (TAN) as a single genomic unit from productively infected Molt 4 (clone 8) cells, and sequence analysis confirmed the integrity of all major open reading frames, except vpr which contained an in-frame stop codon. The proviral clone was also biologically active since transfection yielded replication-competent virions. Amino acid sequence comparisons of all major viral proteins indicated that TAN was roughly equidistant from previously characterized sabaeus, grivet, and vervet strains, thus confirming that it represents a fourth independent SIVAGM lineage. Given the need for well-characterized reference reagents, this full-length tantalus provirus should facilitate future studies of SIVAGM molecular biology and evolution.

Animals↗

PubMed1997

Bronchial casts in children: a proposed classification based on nine cases and a review of the literature.

Bronchial casts are characterized by the formation of obstructive airway plugs that may be large enough to fill the branching pattern of an entire lung. The condition is rare but can occur at any age. Casts may be secondary to underlying diseases such as asthma and cystic fibrosis, but there are often no predisposing factors. There is no accepted classification system for bronchial casts; but only a confusion of descriptive terms such as mucoid impaction, fibrinous bronchitis, and pseudomembranous bronchitis. Based on a review of nine well-documented cases and the available literature, we have separated bronchial casts into two well-defined groups: Type 1 (inflammatory), consisting of casts composed mainly of fibrin with a dense eosinophilic inflammatory infiltrate; and Type 2 (acellular), consisting of casts composed mainly of mucin with little or no cellular infiltrate and occurring only in children with congenital cyanotic heart disease. Acute mortality was high in both groups. Survivors of Type 1 casts seem to be well controlled with inhaled steroids. Optimal therapy for patients with Type 2 casts is not clear; the prognosis probably depends on underlying cardiac status. We hope that this simple classification will provide a framework for further study of this obscure condition.

Adolescent↗

PubMed1997

Effects of recombinant human transforming growth factor-beta 1 or/and interleukin-6 on growth inhibition and proto-oncogene c-myc expression in human leukemia cells.

OBJECTIVE: To examine the effect of recombinant human transforming growth factor-beta 1 (rhTGF-beta 1) alone or recombinant human interleukin 6 (rhIL-6) alone or in combination on proliferation inhibition of the human leukaemia cell line. METHODS: In the present study, using the human monoblastic cell line (U937) and human promyelocytic cell line (HL60) as an in vitro model, we analyzed the effect of two cytokins on proliferation inhibition with rate of 3H-TdR incorporation, the cellular content of DNA, DNA indices, the cell cycle and the expression of c-myc mRNA. RESULTS: With administration of rhTGF-beta 1 and rhIL-6, U937 cell growth was inhibited and the rate of 3H-TdR incorporation inhibition was increased. There was a decrease in the cellular content of DNA and DNA indices. And no change in the cell cycle was observed after administration of rhTGF-beta 1 or rhIL-6. However, there was an increase in G0/G1 phase cells and a decrease in G2M + S phase cells after administration of combination of rhTGF-beta 1 and rhIL-6. It was also found that rhIL-6 could inhibit proliferative responses of HL60 cells, meanwhile the inhibition could be enhanced by rhTGF-beta 1. The rate of 3H-TdR incorporation inhibition rose up to 39.89%, and DNA index fell to 1.00 following induction by rhIL-6 plus rhTGF-beta 1. Furthermore, G0/G1 phase cells increased while G2M + S cells decreased. CONCLUSIONS: These results suggest that combination of rhTGF-beta 1 and rhIL-6 acted in synergy to inhibit proliferation of both U937 and HL60 cell lines. Molecular hybridization test show that rhTGF-beta 1 alone, rhIL-6 alone or rhTGF-beta 1 and rhIL-6 in combination can inhibit U937 and HL60 cells expression of c-myc mRNA in a time and dose dependent manner. rhTGF-beta 1 and rhIL-6 in combination synergistically inhibited c-myc expression, which may be one of the machanisms for the actions of the two cytokines.

Cell Division↗