Evidence that an OX-2-positive cell can inhibit the stimulation of type 1 cytokine production by bone marrow-derived B7-1 (and B7-2)-positive dendritic cells

We reported that hepatic mononuclear, nonparenchymal cells (NPC) can inhibit the immune response seen when allogeneic C57BL/6 dendritic cells (DC) are incubated with C3H spleen responder cells. Cells derived from these cultures transfer increased survival of C57BL/6 renal allografts in C3H mice. We also found that increased expression of OX-2 on DC was associated with inhibition of cytokine production and renal allograft rejection. We explored whether inhibition by hepatic NPC was a function of OX-2 expression by these cells. Fresh C57BL/6 spleen-derived DC were cultured with C3H spleen responder cells and other putative coregulatory cells. The latter were derived from fresh C3H or C57BL/6 liver NPC, or from C3H or C57BL/6 mice treated for 10 days by i.v. infusion of human Flt3 ligand. Different populations of murine bone marrow-derived DC from cultures of bone marrow with IL-4 plus granulocyte-macrophage-CSF were also used as a source of putative regulator cells. Supernatants of all stimulated cultures were examined for functional expression of different cytokines (IL-2, IL-4, IFN-gamma, and TGFbeta). We found that fresh C57BL/6 splenic DC induced IL-2, not IL-4, production. Cells from the sources indicated inhibited IL-2 and IFN-gamma production and promoted IL-4 and TGFbeta production. Inhibition was associated with increased expression of OX-2 on these cells, as defined by semiquantitative PCR and FACS analysis. By size fractionation, cells expressing OX-2 were a subpopulation of NLDC145+ cells. Our data imply a role for cells expressing OX-2 in the regulation of induction of cytokine production by conventional allostimulatory DC.

Identification and characterization of a new splicing variant of vascular endothelial growth factor: VEGF183

We report the discovery of a new splicing variant of vascular endothelial growth factor named VEGF183. It is six amino acids shorter than its closest relative, VEGF189, due to the utilization of a conserved alternate splicing donor site within exon 6a. Highly expressed in heart tissue, VEGF183 is detected in transiently transfected COS cells as 28-32-kDa monomers under reduced condition, and 46-kDa dimers under non-reduced condition - the functional unit for all VEGF isoforms.

[Analysis of clincal poliomyelitis in Shandong Province from 1993-1996]

Wild poliovirus has not been isolated in Shandong province since Apr. 1991. However, 71 clinically polio cases were diagnosed by an expert group, including 50 potential Vaccine Associated Paralytic Poliomyelitis (VAPP) including 31 having the sabin strain in the stools, from 1993 to 1996. The overall frequency of VAPP was one case per 1.25 million doses distributed. The relative frequencies of first dose in the OPV series was one case per 218,800 doses vs one case per 1.01 million for second dose. Based on data from the 31 cases, we estimated that the rates had been one case per 438,000 first dose and one case per 6.42 million second dose and one case per 10.44 million among the contacts of the cases. This results seemed to be higher than from other reports. Clinically confirmed poliomyelitis cases in Shandong were diagnosed by the experts group. The classification of clinical polio cases is important in the polio eradication program.

[Determination of levofloxacin in plasma and cerebrospinal fluid with HPLC and its pharmacokinetics in patients undergoing neurosurgical operations]

A RP-HPLC method was developed to determine the concentrations of levofloxacin in plasma and cerebrospinal fluid and its pharmacokinetics were studied in patients undergoing neurosurgical operations. C18H37 column was eluted with the mobile phase consisting of 10 mmol.L-1 KH2PO4-10 mmol.L-1(C4H9)4Br-CH3CN(45:45:10, pH 3.0) and the utraviolet absorbance was monitored at 295 nm. Ciprofloxacin was used as internal standard. The mean recoveries were 74.76% in plasma and 82.43% in cerebrospinal fluid, with the lowest detectable limits of 10 micrograms.L-1 and 6 micrograms.L-1, respectively. The RSD for the intra-day and inter-day were all less than 5%. A single oral administration of 300 mg levofloxacin tablet was given to 10 patients undergoing neurosurgical operations. The pharmacokinetic parameters in blood and in cerebrospinal fluid could be described by one compartment open model. The pharmacokinetic parameters were: blood Ke 0.12 +/- 0.04 h-1, T1/2 6.05 +/- 1.68 h, Tmax 1.05 +/- 0.29 h, Cmax 3.67 +/- 0.42 mg.L-1, AUC 33.43 +/- 7.32 mg.h.L-1, CLs 9.46 +/- 2.53 L.h-1, Vd 77.49 +/- 7.39 L; cerebrospinal fluid Ke 0.11 +/- 0.04 h-1, T1/2 6.95 +/- 1.88 h, Tmax 3.56 +/- 1.24 h, Cmax 1.68 +/- 0.25 mg.L-1, AUC 23.70 +/- 5.62 mg.h.L-1, CLs 13.70 +/- 5.11 L.h-1, Vd 126.61 +/- 13.20 L.

Advances in TCM treatment of hyperprolactinemia

In recent years, rapid progress has been seen in the treatment of hyperprolactinemia with TCM and materia medica. The old pattern of simply using bromocryptine to treat the disease has been changed. Most of the cases reported in this paper were primary hyperprolactinemia, with other primary diseases excluded. As TCM treatment produces definite therapeutic effects with few side-effects, the methods above reported are worth recommending.

[Experimental study on the efficacy of methyl prednisolone in the treatment of traction injury of spinal cord in rabbits]

In order to study the prophylactic and therapeutic effect of methyl-prednisolone (MP) on traction injury of spinal cord, 48 rabbits were divided into four groups randomly. According to decreasing amount of the amplitude of P1-wave, 50% reduction lasted for 5 min and 10 min with MP as experimental group, and 50% 5 min and 10 min with NS as control, the changes of amplitudes were monitored by, and the function of the spinal cord was assessed. The amounts of MDA and SOD of the spinal cord tissue were determined and the pathomorphological changes of the spinal cord were observed. The results showed that in the experimental groups, the recovery of P1-wave was quicker, the Tarlov and Molt value were decreased, the density of gray matter of the anterior horn and the myelinated nerve fiber of white matter of 100 microns diameter were higher, the SOD and MDA was decreased and the degenerative and necrotic degree of neuron and nerve fiber were milder. Where in the control groups all the above items were just on the opposite. The conclusions list as follows: the application of MP before operation of spinal deformity might prevent traction injury of the spinal cord during operative correction of spinal deformity, and could also minimized the secondary damage to spinal cord from traction injury if MP was used in time. The action to MP were summarized as improving the microcirculation, inhibiting the hyperoxidation of lipid and accelerating the recovery of SCEP.

Estradiol reverses TGF-beta1-stimulated type IV collagen gene transcription in murine mesangial cells

We have previously shown that estradiol suppresses types I and IV collagen synthesis by mesangial cells grown in the presence of serum. In the present study, we examined the interaction between estradiol and transforming growth factor-beta (TGF-beta) on collagen IV synthesis. In a luciferase reporter gene construct containing the type IV collagen promoter and 1-chain regulatory sequences, we found that TGF-beta1 (2 ng/ml) stimulated alpha1-collagen IV gene transcription in serum-free media (140.5 +/- 6.2 relative luciferase units, expressed as a percent of control untreated cells, P < 0.001). Estradiol reversed the stimulatory effects of TGF-beta1 on reporter gene transcription in a dose-dependent manner [for 2.5 x 10(-9) M, 114.2 +/- 0.2, P < 0.002 vs. TGF-beta1; for 10(-7) M, 89.5 +/- 4.0, P < 0.001 vs. TGF-beta1 and P = not significant (NS) vs. control]. Using immunoprecipitation techniques, we found that estradiol (10(-7) M) reversed TGF-beta1-stimulated type IV collagen synthesis (175.3 +/- 14.7 vs. 111.6 +/- 7.1, expressed as a percent of control untreated cells, P < 0.001) but did not affect TGF-beta1-stimulated type I collagen synthesis (166.9 +/- 18.8 vs. 162.2 +/- 16.2, P = NS). These results were confirmed with Western blotting. Nuclear extracts from mesangial cells treated with TGF-beta1 showed increased binding to a Sp1 consensus binding sequence oligonucleotide and to an Sp1 binding site in the collagen IV promoter. Estradiol reversed this enhanced binding. These data suggest that estradiol antagonizes TGF-beta1-stimulated type IV collagen synthesis at a transcriptional level and that this effect may be mediated by interactions with the transcription factor Sp1.

Rapid verification of disulfide linkages in recombinant human growth hormone by tandem column tryptic mapping

An automated tryptic mapping method was developed for characterization of disulfide linkages in recombinant human growth hormone (rhGH). The hormone was trypsin digested and the peptide fragments concentrated by eluting rhGH through an immobilized trypsin column and transferring the peptides directly to a reversed-phase liquid chromatography (RP-LC) column where they were collected. Reaction time was controlled by the flow-rate. Following tryptic digestion of a sample, the immobilized enzyme column was uncoupled from the flow train by a switching valve and the RP-LC column eluted with a solvent gradient ranging from 0.1% trifluoroacetic acid (TFA) with 1% acetonitrile (ACN) to ACN with 0.1% TFA and 5% water. This two-step mapping process was achieved within 2 h on both native and reduced rhGH samples. The chromatographic elution position and mass spectra matrix-assisted laser desorption ionization time-of-flight mass spectrometry of native rhGH and sulfur-containing peptides were determined with standards. Standards of the individual sulfhydryl (-SH) containing peptides and all possible disulfide linked peptides that could result from coupling the -SH peptides in disulfide linkages were obtained by synthesis and chromatographic purification. This approach allowed the chromatographic elution position of all possible mismatched disulfide containing peptides to be established and samples of rhGH to be examined for improper folding.

Serum-stimulated alpha 1 type IV collagen gene transcription is mediated by TGF-beta and inhibited by estradiol

We examined the hypothesis that fetal calf serum (FCS) stimulates murine mesangial cell alpha 1 type IV collagen (COL4A1) gene transcription by increasing autocrine production of transforming growth factor-beta (TGF-beta) through a platelet-derived growth factor (PDGF)-dependent mechanisms. PDGF-stimulated COL4A1 gene transcription was inhibited by neutralizing antibody to TGF-beta (119.3 +/- 3.6 vs. 106.0 +/- 6.2 relative luciferase units, expressed as a percentage of control untreated cells, P < 0.003). FCS-stimulated gene transcription was inhibited by neutralizing antibody to PDGF (148.3 +/- 4.1 vs. 136.7 +/- 0.3 relative luciferase units, P < 0.002) and by neutralizing antibody to TGF-beta (148.3 +/- 4.1 vs. 127.1 +/- 3.4 relative luciferase units, P < 0.036). The inhibitory effect of combined treatment with anti-PDGF and anti-TGF-beta antibody on gene transcription was no greater than that of anti-TGF-beta antibody alone [129.5 +/- 0.53 vs. 127.1 +/- 3.4 relative luciferase units, P = not significant (NS)]. FCS-stimulated gene transcription was also inhibited by estradiol (10(-7) M) (148.4 +/- 3.1 vs. 119.4 +/- 8.1 relative luciferase units, P < 0.019). In the presence of estradiol, anti-TGF-beta antibody failed to further reduce serum-stimulated gene transcription (119.4 +/- 8.1 vs. 115.6 +/- 9.8, P = NS), suggesting that estradiol reverses FCS-stimulated COL4A1 gene transcription by antagonizing the actions of TGF-beta. Measurement of type IV collagen synthesis by Western blotting confirmed that the intact gene responded in a manner analogous to the promoter construct.

Modulation of transcription factor Sp1 by cAMP-dependent protein kinase

Transcription factor Sp1 is a phosphoprotein whose level and DNA binding activity are markedly increased in doxorubicin-resistant HL-60 (HL-60/AR) leukemia cells. The trans-activating and DNA binding properties of Sp1 in HL-60/AR cells are stimulated by cAMP-dependent protein kinase (PKA) and PKA agonists and inhibited by PKA antagonists as well as by the PKA regulatory subunit. Reporter gene activity under the control of the Sp1-dependent SV40 promoter is stimulated in insect cells transiently expressing Sp1 and PKA, and the DNA binding activity of recombinant Sp1 is activated by exogenous PKA in vitro. These results indicate that Sp1 is a cAMP-responsive transcription factor and that Sp1-dependent genes may be modulated through a cAMP-dependent signaling pathway.

Sex hormones and renal nitric oxide synthases

The present study was undertaken to determine whether sex hormones influence nitric oxide synthase levels in the kidney. Five groups of rats were studied: males, castrated males, females, oophorectomized females, and oophorectomized females receiving estradiol replacement therapy. Endothelial nitric oxide synthase (eNOS) levels in the kidney were measured by Western blotting. eNOS levels were significantly greater in the renal medulla of female rats compared with male rats (3545 +/- 473 versus 2418 +/- 205 densitometry units (DU), P < 0.05). Oophorectomy reduced renal medullary eNOS levels to that of intact male rats (2566 +/- 304 DU, P = NS). Estrogen replacement therapy significantly increased medullary eNOS levels in oophorectomized animals (3249 +/- 377 versus 2302 +/- 213 DU, P < 0.05). Renal inducible nitric oxide synthase (iNOS) levels were measured after induction with lipopolysaccharide. iNOS levels were significantly greater in the renal medulla of female rats compared with male rats (677 +/- 253 versus 252 +/- 12 DU, P < 0.05). Oophorectomy reduced renal medullary iNOS levels to that of intact male rats (295 +/- 57 DU, P = NS). In contrast, estrogen replacement therapy significantly increased medullary iNOS levels in oophorectomized animals (682 +/- 356 versus 160 +/- 92 DU, P < 0.05). Steady-state levels of mRNA for iNOS were found to be higher in the inner medulla of female rats compared with male rats (1519 +/- 211 versus 899 +/- 105 DU, P < 0.05). In contrast to these findings, sex hormones failed to influence nitric oxide production or iNOS levels in lipopolysaccharide-stimulated mesangial cells in culture. These results suggest that gender may influence renal medullary synthesis of nitric oxide.

FHIT gene alterations in esophageal cancer and ulcerative colitis (UC)

FHIT (fragile histidine triad gene), a candidate tumor suppressor gene, was recently identified and cloned at chromosome 3p14.2. Alterations of this gene have been reported in a number of primary human tumors, including colorectal, esophageal, gastric and lung carcinomas. However, some reports have found no abnormalities in this gene. We investigated a total of 63 primary esophageal tumors, nine esophageal cancer cell lines and 17 ulcerative colitis-associated neoplasms (UCANs) for alterations of FHIT. In 13 esophageal tumors, we employed overlapping reverse transcriptase-PCRs (RT-PCRs) to amplify and sequence the complete open reading frame of FHIT. One of 13 primary esophageal tumors analysed by RT-PCR expressed no detectable FHIT transcript; the remaining 12 expressed normal-sized transcripts with wild-type open reading frame sequences. In an additional 50 esophageal tumors, the polymorphic microsatellite loci D3S1300 and D3S1313 were used to evaluate loss of heterozygosity (LOH) at 3p14.2. Eleven of these 50 tumors showed LOH at one or both loci. In all these 11 tumors, genomic PCR and direct sequencing of FHIT exons 5-9 was performed. This analysis revealed that none of these 11 primary esophageal tumors contained any alterations in the FHIT open reading frame or adjacent intron sequences. Finally, among 17 UCANs, the in vitro synthesized protein (IVSP) assay detected no truncated protein products, nor were there any abnormalities in size or DNA sequence of FHIT RT-PCR products. However, in six of nine esophageal carcinoma cell lines, no FHIT RT-PCR product was detectable using either of the overlapping primer sets. Genomic PCR and direct sequencing of exons 5-9, also performed in these nine cell lines, revealed wild-type sequence in eight cell lines; however, one cell line contained no exon 5 PCR product. This cell line also lacked detectable FHIT transcript. These data suggest that the open reading frame of FHIT is not important in the development or progression of most primary esophageal carcinomas or UCANs, although lack of expression of the FHIT transcript may be common in esophageal cancer-derived cell lines. The possibility of an additional tumor suppressor gene at chromosome 3p14.2 remains to be evaluated.

Apparent protection from instability of repeat sequences in cancer-related genes in replication error positive gastrointestinal cancers

Genomic instability at simple repeated sequences has been observed in various types of human cancers and is considered an important mechanism in tumorigenesis. Alterations at microsatellite loci have been reported scattered throughout the genome. Recently, the transforming growth factor-beta receptor type II (TGF-beta RII) and the insulin-like growth factor II receptor (IGF-IIR) genes were shown to have inactivating mutations within coding microsatellite sequences. The demonstration of mutations in two growth regulatory genes supports the idea that other regulatory genes with repeat sequences may also be targets in tumours with defective mismatch repair. We examined genes involved in tumour suppression, cell adhesion and cell cycle regulation for mutations at small repeat sequences in replication error positive gastrointestinal cancers. Several polymorphisms were found which exhibited instability, but no other instability was present in the regions examined.

Effects of sex hormones on fluid and solute transport in Madin-Darby canine kidney cells

Polycystic kidney disease progresses more rapidly in men than in women. To investigate the basis for this sexual dimorphism, we exposed Madin-Darby canine kidney (MDCK) cells grown on collagen-coated cell culture inserts to control media, or to estradiol or testosterone (1 nM-1 microM). Compared to control and estradiol-treated cells, testosterone stimulated fluid secretion in a dose-dependent manner, enhancing fluid secretion 4.8-fold at 1 nM and 19.7-fold at 1 microM (0.59 +/- 0.18 vs. 0.03 +/- 0.01 microliter/cm2/hr, P < 0.001). Chloride transport paralleled fluid secretion. Testosterone increased cellular cyclic AMP levels 3.2-fold at 1 nM and 12.3-fold at 1 microM (81.3 +/- 30.7 vs. 6.6 +/- 3.3 pmol/mg protein, P < 0.001). GDP beta S (500 microM), an inhibitor of Gs, and 2',3'-dideoxyadenosine (10 microM), an inhibitor of the catalytic subunit of adenylate cyclase, suppressed testosterone-induced fluid and solute secretion. Neither testosterone nor estradiol had any effect on microsomal Na,K-ATPase activity, cellular proliferation or cellular total protein content. Our studies show that testosterone stimulates fluid secretion and solute transport by MDCK cells by increasing cAMP generation. In vivo, testosterone may contribute to cyst expansion by enhancing fluid secretion. This observation may help explain the worse prognosis of polycystic kidney disease observed in men.

A transforming growth factor beta 1 receptor type II mutation in ulcerative colitis-associated neoplasms

BACKGROUND & AIMS

Numerous gastrointestinal tumors, notably sporadic and ulcerative colitis (UC)-associated colorectal carcinomas and dysplasias, gastric cancers, and esophageal carcinomas, manifest microsatellite instability. Recently, a transforming growth factor beta 1 type II receptor (TGF-beta 1RII) mutation in a coding microsatellite was described in colorectal carcinomas showing instability. One hundred thirty-eight human neoplasms (61 UC-associated, 35 gastric, 26 esophageal, and 16 sporadic colorectal) were evaluated for this TGF-beta 1RII mutation.

METHODS

Whether instability was present at other chromosomal loci in these lesions was determined. In lesions manifesting or lacking instability, the TGF-beta 1RII coding region polydeoxyadenine (poly A) microsatellite tract was polymerase chain reaction amplified with 32P-labeled deoxycytidine triphosphate. Polymerase chain reaction products were electrophoresed on denaturing gels and exposed to radiographic film.

RESULTS

Three of 18 UC specimens with instability at other chromosomal loci (17%) showed TGF-beta 1RII poly A tract mutation, including 2 cancers and 1 dysplasia; moreover, 2% of UC specimens without instability (1 of 43) (1 cancer), 81% of unstable sporadic colorectal cancers (13 of 16), and none of the 61 stable or unstable gastric or esophageal cancers contained TGF-beta 1RII mutations.

CONCLUSIONS

Mutational inactivation of the poly A microsatellite tract within TGF-beta 1RII occurs early and in a subset of unstable UC neoplasms and commonly in sporadic colorectal cancers but may be rare in unstable gastric and esophageal tumors.

Substrate specificity and inhibitor sensitivity of Ca2+/S100-dependent twitchin kinases

Myosin-associated giant protein kinases of the titin/witchin-like superfamily have previously been implicated in the regulation of muscle function, based on genetic and physiological studies. We find that recombinant constitutively active Caenorhabditis elegans and Aplysia twitchin kinase fragments differ in their catalytic activities and peptide-substrate specificities, as well as in their sensitivities to the naphthalene sulfonamide inhibitors 1-(5-chloronaphthalenesulfonyl)-1H-hexahydro-1,4-diazepine (ML-7) and 1-(5-iodonaphthalenesulfonyl)-1H-hexahydro-1,4-diazepine (ML-9). The constitutively active Aplysia twitchin kinase fragment has a remarkably high activity (Vmax > 100 mumol.min-1.mg-1) towards some substrate peptides. The autoinhibited forms of these twitchin kinases can be activated in a Ca(2+)-dependent manner by the dimeric form of the S100A1 protein (S100A1(2)). The twitchin kinase S100A1(2)-binding site can also bind Ca2+/calmodulin but neither kinase is activated by calmodulin. The data provide a functional basis for the ongoing crystallographic study of twitchin kinase fragments.

Infrequent DPC4 gene mutation in esophageal cancer, gastric cancer and ulcerative colitis-associated neoplasms

Homozygously Deleted in Pancreatic Cancer 4 (DPC4), a recently identified candidate tumor suppressor gene, was previously shown to be altered in human pancreatic cancers. We examined DPC4 mutation in 30 examples of three other types of gastrointestinal malignancy: 10 esophageal cancers, 10 gastric cancers and 10 colorectal cancers occurring in the preneoplastic condition, ulcerative colitis. The entire coding region of DPC4 (including all 11 exons) was analysed by either direct sequencing of PCR product or the in vitro synthesized protein assay. No coding region mutations of DPC4 were found in any of the samples examined. Our results suggest that inactivation of DPC4 may not be important in the majority of these types of gastrointestinal cancer.

[The characteristics of macular branch retinal vein occlusion]

OBJECTIVE

The study was designed for the analysis on data of 51 patients with macular branch retinal vein occlusion (McBRVO) and the comparison between them and 210 patients (214 eyes) with major branch retinal vein occlusion (MjBRVO).

METHODS

Fluorescein angiography, ophthalmoscope and slit-lamp were used for the examination of the venous obstructive site and the locations of artery and vein.

RESULTS

(1) The incidence of McBRVO was 19.5% (51/261) in branch retinal vein occlusion. (2) The site of occlusion: the incidence of McBRVO at supero-temporal branches was 72.5% (37/51) and the incidence of MjBRVO was 73.4% (157/214). (3) The involved branch at the first macular branch accounted for 39.6%, the second branch 58.3%, and the third branch 2.1%. The artery anterior to the vein at arteriovenous crossing at the obstructive site accounted for 93.0% in the McBRVO group and 95.0% in the MjBRVO group. (4) The complications and visual prognosis: The incidence of cystoid macular edema was 20.0% in McBRVO group and that was 28.5% in the MjBRVO group. No neovascularization was found in the McBRVO group, while 37.9% neovascular formation was found in the MjBRVO group. The visual acuity recovered to 0.5 or better was in 88.2% in the McBRVO group, while 57.0% in the MjBRVO group (P < 0.005).

CONCLUSION

There are no significant differences in sex, age, laterality, pathogenesis as well as occlusion site between the McBRVO and MjBRVO groups, but the visual prognosis is better in the former than that in the latter group.

Effects of sex hormones on mesangial cell proliferation and collagen synthesis

In a variety of renal diseases, males progress at a more rapid rate and have a more fulminant course than females. This gender difference may be related to the direct effects of sex hormones on the cells of the kidney. To evaluate this hypothesis, we studied the effects of estrogens and testosterone on mesangial cell proliferation and collagen synthesis. At 48 hours, estradiol at 10 nM and 100 nM had a modest proliferative effect on cultured mesangial cells, as measured by 3H thymidine incorporation into DNA and direct cell counting. This estradiol effect was fully reversed by Tamoxifen (1 microM). Estradiol had no effect on cellular proliferation at 1 microM concentrations, but suppressed proliferation at 10 microM doses. Testosterone had a modest but statistically insignificant effect on proliferation at 10 nM and 100 nM concentrations but no effect at 1 microM or 10 microM. Neither estradiol nor testosterone at 10 microM affected total cellular protein accumulation. Estradiol at 1 microM and 10 microM, markedly suppressed total collagen synthesis as measured by 3H proline incorporation, and specifically suppressed the synthesis of collagen types I and IV, as measured by immunoprecipitation and gel electrophoresis. Testosterone did not affect collagen synthesis. Estradiol also reduced the steady state message for the alpha 2 chain of type I collagen, while testosterone had no effect. Neither estradiol nor testosterone affected the steady state message for TGF beta or EGF. The direct effects of estradiol on mesangial cell collagen generation may help explain the slower development of glomerulosclerosis in women and therefore the "protective" effect of female gender on the progression of renal disease.

Alterations of transforming growth factor-beta 1 receptor type II occur in ulcerative colitis-associated carcinomas, sporadic colorectal neoplasms, and esophageal carcinomas, but not in gastric neoplasms

BACKGROUND & AIMS

Gastric cancers, sporadic colorectal cancers, and ulcerative colitis (UC)-associated colorectal carcinomas and dysplasias manifest microsatellite instability (MI); however, esophageal carcinomas rarely exhibit MI. Recently, a transforming growth factor-beta 1 type II receptor (TGF-beta 1RII) mutation in a coding microsatellite was described in primary colorectal carcinomas demonstrating MI. No previous studies of TGF-beta 1RII have addressed mechanisms of inactivation other than MI in human tumors; furthermore, MI-negative tumors have not been examined for TGF-beta 1RII mutation. We evaluated 138 primary human neoplasms for mutation in the poly-A microsatellite tract of TGF-beta 1RII. Additionally, a group of esophageal tumors was evaluated for the expression of TGF-beta 1RII messenger RNA (mRNA).

METHODS

First, we determined whether MI was present at other chromosomal loci in these lesions. The poly-deoxyadenine (poly-A) microsatellite tract within the TGF-beta 1RII coding region was then PCR-amplified. In a group of MI-negative esophageal tumors, RT-PCR was performed to determine the expression of TGF-beta 1RII mRNA.

RESULTS

Among 17 MI+ UC specimens, 3 (18%) demonstrated TGF-beta 1RII poly-A tract mutation (2 cancers and 1 dysplasia), while 2 (4%) of 44 MI-negative UC specimens (1 dysplasia and 1 tumor), and 13 (81%) of 16 MI+ sporadic colorectal cancers, contained TGF-beta 1RII poly-A mutation. No gastric or esophageal tumors contained TGF-beta 1RII mutation. Among 21 MI-negative esophageal carcinomas. 6 cases (28.5%) had TGF-beta 1RII transcripts that were low or undetectable by RT-PCR.

CONCLUSIONS

Mutation within the poly-A microsatellite tract of TGF-beta 1RII occurs early in a subset of UC-neoplasms and commonly in sporadic colorectal cancers, but may be rare in MI+ gastric tumors. Diminished expression of TGF-beta 1RII mRNA in esophageal tumors suggests that mechanisms of inactivation in this gene other than MI play a role in esophageal carcinogenesis.

Expression and function of autocrine motility factor receptor in human choriocarcinoma

OBJECTIVE

Our purpose was to determine whether human choriocarcinoma cells express autocrine motility factor receptor (AMF-R) and to study its function in this tumor system.

STUDY DESIGN

The expression and localization of AMF-R were compared in choriocarcinoma and normal placental trophoblasts using both cell lines and tissue sections. In addition, migratory properties of choriocarcinoma cells and normal placental cells was determined.

RESULTS

Using immunofluorescence and immunoperoxidase staining, we have detected the expression of AMF-R in choriocarcinoma cells with receptor clustering on the cell surface, while term placenta cells expressed AMF-R less intensely with no receptor clustering. In choriocarcinoma tissues, AMF-R was strongly expressed in malignant cytotrophoblasts cells while adjacent normal villous trophoblast cells and necrotic regions were weakly or negatively stained. Choriocarcinoma cells responded to AMF-R stimulation with increased cell motility, while term placental cells were unresponsive.

CONCLUSION

Human choriocarcinoma cells express functional cell surface AMF-R in vitro and in choriocarcinoma tissue suggesting that this receptor may play an important role in cancer cell motility.

Effects of tumor necrosis factor-alpha on human trophoblast cell adhesion and motility

PROBLEM

Adhesive interaction between trophoblast cells and uterine endometrial basement membrane is one of the critical processes in embryo implantation. This interaction is directly or indirectly regulated by hormones, growth factors, and cytokines. Since tumor necrosis factor-alpha (TNF-alpha) is synthesized by both decidual and trophoblast cells, we hypothesized that TNF-alpha may play a regulatory role in trophoblast cell invasion. To test this hypothesis, we have used in vitro models to determine the effect of TNF-alpha on human trophoblast cell adhesion and motility, two major steps in trophoblast invasion.

METHODS

The effect of TNF-alpha on the motility of extended-lifespan first trimester trophoblasts (HTR) and JEG-3 choriocarcinoma cells was tested using the phagokinetic track motility assay. An in vitro adhesion assay was used to determine the effect of TNF-alpha on the adhesion of HTR and JEG-3 cells to laminin, a major basement membrane component. In addition, the effect of TNF-alpha on the surface expression of the laminin receptor beta 1 integrin subunit was examined using flow cytometry.

RESULTS

HTR or JEG-3 cells strongly adherent to laminin which was not significantly altered by TNF-alpha treatment. We also measured the effect of TNF-alpha on the surface expression of beta 1 integrin on HTR and JEG-3 cells; no difference was observed between control and treatment groups. Interestingly, the motility of both HTR and choriocarcinoma JEG-3 cells was significantly inhibited by TNF-alpha.

CONCLUSIONS

The role of TNF-alpha in human embryo implantation is currently unknown. Our data demonstrate that TNF-alpha does alter trophoblast cell adhesion to laminin, but significantly inhibits trophoblast cell motility in vitro, suggesting that TNF-alpha may play a regulatory role in trophoblast cell invasion.

Growth suppression of esophageal cancer cells by p16INK4 and p15INK4B in vitro

PURPOSE

We investigate whether p16INK4 and p15INK4B inhibit cellular proliferation and exert a growth suppressive effect on esophageal cancer cells.

MATERIALS AND METHODS

The growth suppressive effects of p16INK4 and p15INK4B were evaluated by transfecting vectors containing the p16INK4 cDNA or the p15INK4B cDNA, or both, constitutively driven by a cytomegalovirus promoter, into two human esophageal cancer cell lines containing or lacking endogenous p16INK4 and/or p15INK4B.

RESULTS

These experiments demonstrated that in both cells lines tested, the numbers of cells surviving dramatically decreased in p16INK4-transfected and p15INK4B-transfected cells compared with control vector-transfected cells. There was no significant difference in the degree of growth inhibition between p16INK4-transfected and pI5INK4B-transfected cell lines.

CONCLUSIONS

These results suggest that p16INK4 and p15INK4B play important roles in the initiation or promotion of esophageal cancer. The inactivation of p16INK4 and p15INK4B may contribute to uncontrolled growth in human cancer.

[Poliomyelitis surveillance in Shandong Province from 1991-1994]

After a series of poliomyelitis outbreaks came about in Shandong province from 1988 to 1990, comprehensive measures including establishment of acute flaccid paralysis (AFP) surveillance system, introduction of mass immunization campaign of oral poliovirus vaccine (OPV) and enhancing management of poliomyelitis eradication activity, were carried out. The incidence of poliomyelitis decreased with the reported number of cases 95, 25, 22 and 17, in 1991, 1992, 1993 and 1994, respectively. A geographically sporadic distribution was noticed with no peak on seasonality. No confirmed case caused by wild poliovirus was identified from 1991 to 1994. Reporting incidence of AFP cases among children under 15 years old was increasing gradually with 1.00 per 10(5) population in 1993 and 1.89 in 1994. The results showed that the poliomyelitis eradication activity in Shandong province had reached a final stage but much efforts still need to be made to reach the target on poliomyelitis eradication.