[Determination of felodipine concentration in human plasma by GC-ECD and study of its pharmacokinetics]

A rapid, accurate and sensitive gas chromatographic method using electron-capture detector (GC-ECD) was developed for the determination of felodipine concentration in human plasma. Nimodipine was used as internal standard. The plasma samples were extracted using a mixture of ethyl ether and n-hexane (2:1) to give mean recoveries of 97.3% of felodipine. The extracts were separated by a 5% SE-30 glass packed column (2 m x 3 mm). The detection limits for felodipine was 0.25 ng.ml-1. The precisions (RSD%, n = 5) of within-day and day-to-day were less than 5.09% and 8.62%, respectively. The pharmacokinetic parameters of felodipine in ten men were investigated by this method. The concentration-time curve was fitted to a two-compartment model. Its main pharmacokinetic parameters were: T1/2 alpha = 0.76 h, T1/2 beta = 16.09 h, Cmax = 4.78 ng.ml-1, Tmax = 2.01 h, AUC = 45.2 h.ng.ml-1.

[Respiratory muscle function and serum enzymology in hyperthyroidism before and after treatment]

To investigate the effect of hyperthyroidism on respiratory muscle function and its possible mechanism, the thyroid function, serum enzymology, serum potassium, pulmonary function and respiratory muscle function were examined in 60 patients with Grave's disease before treatment and 26 patients among them after treatment, and 20 normal subjects as control. T3, T4, and FT4 increased while FVC and PImax, which reflect the respiratory muscle strength, and Pi/PImax, which reflects the reserve capacity of inspiratory muscle, decreased significantly in the 60 patients with Grave's disease, compared with the ones of normal subjects. The comparison of above measurements in the 26 patients between before- and after-treatment showed that respiratory muscle strength increased obviously along with the improvement of throid function. The serum enzymology, potassium and TSH, however, were not abnormal and not changed after treatment. The thyroid functions in 10 patients with hyperthyroid heart disease were not different, compared with the ones of other 50 patients without hyperthyroid heart disease, but their respiratory muscle strength was significantly lower than the ones of latter. The above results suggested that hyperthyroidism could lead to significant decrease of respiratory muscle strength and its reserve capacity, whereas treatment for hyperthyroidism would improve respiratory muscle function, so the measurement of respiratory muscle function in hyperthyroidism cases might be useful in prediction of hyperthyroid heart disease.

Germline mutations of hMLH1 and hMSH2 genes in patients with suspected hereditary nonpolyposis colorectal cancer and sporadic early-onset colorectal cancer

PURPOSE

The present study was designed to determine the frequency of germline mutations in the hMLH1 and hMSH2 genes in 31 families suspected of having hereditary nonpolyposis colorectal cancer who do not fulfill the criteria of the International Collaborative Group on Hereditary Nonpolyposis Colorectal Cancer but in whom a genetic basis for colon cancer is strongly suspected and 45 patients with sporadic early-onset colorectal cancer who developed colorectal cancer before the age of 40 years without any family history of colorectal cancer.

METHODS

Genomic DNAs were prepared from peripheral blood samples of patients who were tested. All coding exons and exon-intron borders of these two genes were screened, first with the polymerase chain reaction-single-strand conformation polymorphism method, followed by sequencing of the DNA fragments displaying an abnormal single-strand conformation polymorphism pattern.

RESULTS

In 31 families with suspected hereditary nonpolyposis colorectal cancer, we found six different germline mutations in seven unrelated families, including one missense mutation and three frame-shift mutations in the hMLH1 gene and one missense mutation and one frame-shift mutation in the hMSH2 gene. Totally, frequency of mutation was 23 percent, 16 percent and 7 percent in the hMLH1 and hMSH2, respectively. Only one missense mutation of the hMSH2 gene was identified in 45 patients (2 percent) with sporadic early-onset colorectal cancer. The mutation detection rate in families with suspected hereditary nonpolyposis colorectal cancer was significantly higher than that of patients with sporadic early-onset colorectal cancer (P < 0.05).

CONCLUSION

Our definition of suspected hereditary nonpolyposis colorectal cancer is useful in the diagnosis of hereditary nonpolyposis colorectal cancer and for identifying those families who need genetic presymptomatic diagnosis. Our results indicate that it may be important to perform DNA testing in families suspected of having hereditary nonpolyposis colorectal cancer. On the other hand, we only detected a low mutation rate (2 percent) in 45 patients with sporadic early-onset colorectal cancer.

Genetic identification and management of hereditary nonpolyposis colorectal cancer

Hereditary nonpolyposis colorectal cancer (HNPCC) is a syndrome involving a predisposition to cancers of the colon, endometrium and several other extra-colonic sites, accounting for approximately 1-5% of all colorectal cancer cases. It is not easily recognized because of a lack of distinctive clinical markers, making diagnosis and management of this disease problematic. To provide a basis for uniformity in diagnosis of HNPCC, the Amsterdam criteria were proposed and are currently in use. More recently, the discovery of four human mismatch repair genes (hMSH2, hMLH1, hPMS1 and hPMS2) has provided novel insight into the genetic basis of this disease, and raised the possibility of genetic diagnosis for management of HNPCC patients and their family members. This report summarizes the clinicopathologic aspects of HNPCC, reviews the recent genetic findings and surveillance strategies, and suggests a novel designation of certain patients as suspected HNPCC.

Reversion of multidrug resistance in the P-glycoprotein positive breast cancer cell line (MCF-7/ADR) by introduction of hammerhead ribozyme

A hammerhead ribozyme which site-specifically cleaved the GUC position in codon 880 of the mdr1 mRNA was designed. The target site was chosen between the two ATP binding sites, which may be important for the function of the P-Gp as an ATP-dependent pump. A DNA sequence encoding the ribozyme gene was then incorporated into a eukaryotic expression vector (pH beta Apr-1 neo) and transfected into the breast cancer cell line MCF-7/Adr, which is resistant to adriamycin and expresses the MDR phenotype. The ribozyme was stably expressed in the cell line by the RNA dot blotting assay. The result of Northern blot assay showed that the expressed ribozyme could decrease the level of mdr1 mRNA expression by 83.5%; and the expressed ribozyme could inhibit the formation of P-glycoprotein detected by immuno-cytochemistry assay and could reduce the cell's resistance to adriamycin; this means that the resistant cells were 1,000-fold more resistant than the parental cell line (MCF-7), whereas those cell clones that showed ribozyme expression were only 6-fold more resistant than the parental cell line. These results show that a potentially useful tool is at hand which may inactivate MDR1 mRNA and revert the multidrug resistance phenotype.

Disposal options and case-study pathway analyses

This paper presents an overview of alternatives that currently are employed for the disposal of wastes containing enhanced concentrations of naturally occurring radioactive materials (NORM). The application of pathway assessment methodology to the derivation of acceptable cleanup criteria for residual NORM is described. A specific example is provided drawing on experience with a site containing above-background levels of natural uranium-series and thorium-series nuclides. The options for safe, permanent disposal of U and Th bearing NORM waste are discussed and the application of pathway analysis to performance assessment of a typical engineered disposal cell is illustrated. Typical methods for disposal of other NORM waste forms also are described. This includes radium-contaminated wastes from petroleum sludges, uranium milling, and geothermal power plant operation as well as thorium wastes from production of thorium-magnesium alloys.

[Determination of uric acid, creatinine and pseudouridine in human urine by high performance capillary zone electrophoresis]

A simultaneous determination of uric acid, creatinine and pseudouridine in human urine by high performance capillary zone electrophoresis(HPCZE) is described. The urine samples were refrigerated and filtered. Then the samples were directly introduced into the capillary and a phosphate buffer solution(pH 6.1) was employed. The capillary used was 36 cm x 50 microns i.d. and detection was carried out with a UV monitor at 210 nm. The calibration curve showed a good linearity for uric acid, creatinine, and pseudouridine in the concentration range of 2-80 mg/L and their correlation coefficients were 0.996, 0.996 and 0.999 respectively. Within day CV for assaying the urine samples of uric acid, creatinine and pseudouridine were 5.0%, 3.0%, and 4.4%, and the corresponding between day data were 6.5%, 5.9%, and 5.3%, respectively. The recoveries of uric acid, creatinine and pseudouridine were 99.0%, 102.%, 92.2%, respectively. The total time for separation and determination was within 10 min. This method is characterized by direct assay of urine samples without any pretreatment. The results show that HPCZE is a simple, rapid, sensitive and reliable assay method.

[The relation between nutrition and pulmonary ventilation in patients with chronic obstructive pulmonary disease during the relieved period]

To observe the effect of nutrition on pulmonary ventilation in aged patients with chronic obstructive pulmonary diseace (COPD) during the relieved period, the pulmonary function (MVV, PVC, FEV1, MMEF) of 261 aged patients with COPD was tested during the relieved period. The results showed that the MVV (48.75% +/- 19.9%) tested in the patients with malnutrition was significantly lower than that tested in the patients with normal nutrition (59.1% +/- 22.6%) (P < 0.01) while there was no marked difference in the ventilation in their large and small airway. It is conluded that malnutrition of the patients with COPD affects the constrictive function of respiratory muscle and thus results in a decrease in MVV.

[Determination of tranilast in human plasma by reversed-phase high performance liquid chromatography and its pharmacokinetics]

A simple and rapid method for the determination of tranilast in human plasma by RP-HPLC is described. The analytical column was packed with YWG-C18. The mobile phase consisted of methanol-0.02 mol/L KH2PO4(60:40, V/V; pH 4.2), and detected by UV detector at a wavelength of 333 nm. The plasma sample was injected directly into the HPLC system after precipitation of the protein with methanol. The calibration curve was linear within the concentration range of 0.625-40 mg/L. The average recovery was 100.0% +/- 4.1%, and minimum detectable concentration was 0.2 mg/L. By using this method, the pharmacokinetics of tranilast in the plasma of ten healthy volunteers after oral administration of 200 mg drug were studied. The plasma drug concentration-time curve of volunteers conforms to one-compartment open model.

Study on amino acid composition of HSP70 and the level of plasma free amino acids of workers with long-term exposure to harmful factors

In order to know the practical value of heat stress protein 70 (HSP70) and to know the changes of plasma free amino acids of workers with the induction of HSP70 by harmful factors, the amino acid composition of major HSP, HSP70 purified from the heated cultured human leukemia cancer cell line K562, rabbit liver, rat liver and heart, and mouse liver with two-step procedures of DE52-cellulose ion exchange chromatography and affinity chromatography on ATP-agarose was examined. The level of plasma free amino acids of workers with long-term exposure to heat, carbon monoxide and the combined effect of both heat and carbon monoxide was also investigated. The results showed that the three richest amino acids in HSP70 of all origins were Gly, Glu and Asp, except that of rat heart which was rich in Gly, Phe and Glu. Additionally, Lys, Val, Leu and Ala were also found very rich in HSP70 of all origins. Compared with controls, the most of plasma free amino acids tended to increase and free methionine and tryptophan were increased significantly (P < 0.05) after a long-term exposure to heat, carbon monoxide, and both. These findings suggested that further studies need to be done to find the substances or drugs which induce the synthesis of HSP70 and reduce the inhibition of synthesis of normal proteins for the purpose of protecting people with exposure to harmful factors against the damage of the factors.

Experimental study on intramuscular injection of eukaryotic expression vector pcDNA3- IL-6 on BXSB mice

OBJECTIVE

To study the role of IL-6 in systemic lupus erythematosis (SLE).

METHODS

We constructed eukaryotic expression vector pcDNA3- IL-6 encoding for IL-6 and injected it intramuscularly into BXSB mice. 22 of the 3.5-month-old male BXSB mice were divided into two groups. One group was injected with the pcDNA3-IL-6 100 micrograms per mouse twice at the interval of 20 days. Another group was injected with plasmid pcDNA3 at the same time as control. The ANA and proteinuria were monitored every 10 days, and the IL-6 activity in serum, IgG, C3 deposition and IL-6 expression in kidney detected at the 40th day.

RESULTS

IL-6 encoding plasmid had harmful effects on murine SLE with increased ANA level, proteinuria, IgG, C3 deposition and IL-6 expression in kidney, but there was no difference of serum GPT levels between the two groups.

CONCLUSION

Excessive production of IL-6 could play an important pathogenic role in SLE. Blocking or reducing IL-6 secretion might be a new therapy for SLE.

[Study on expression of IRF-1 gene in human leukemia with RT-PCR and the silver sequence techniques]

OBJECTIVE

To explore preliminarily the changes of IRF-1 gene expression in leukemias.

METHODS

The expression of IRF-1 gene in 24 leukemia patients and 3 leukemic cell lines were studied with RT-PCR and the silver sequence techniques.

RESULTS

No expression of IRF-1 gene in 3 patients, and significantly decreased expressions in 5 patients and in HL-60 and HIMeg cell lines were revealed.

CONCLUSION

The mechanism of human leukemogenesis may be partly associated with no or low-expression of IRF-1 gene.

[The changes of vasoactive intestinal peptide somatostatin and pancreatic polypeptide in blood and CSF of acute cerebral infarction patients and the effect of acupuncture on them]

VIP, SS and PP which exist in gastrointestinal tract and CNS might be to play an important role in nervous system as neurotransmitters of neuromediaters. There have been a few of reports about their changes in plasma and CSF in ICVD. The effects of acupuncture, which was used in treatment of ICVD with good efficiency, on VIP, SS and PP have not been known. For researching their changes in ICVD and effects of electro-acupuncture on them, and finding the mechanism of acupuncture in treatment of ICVD, the study was performed. The levels of VIP, SS and PP in 64 patients with acute cerebral infarction were determined. The points of acupuncture were Quchi (LI 12), Waiguan (SJ 5), Huantiao (BG 30), and Zusanli (ST 36). The routine treatment included dextran, nicotinic acid, aspirin, dipyridamole and radix salviae miltiorrhizae composita. The CSF and blood were taken before the begining of treatments and after a course of treatment. The level of VIP, SS and PP were measured by radiommunoassay. Results showed the level of CSF VIP in the patients was significantly lower as compared with controls. The level of plasma SS in the patients was lower, but the difference was not significant as compared with controls, and level of plasma PP in the patients was significantly increased when it was compared with controls. After electro-acupuncture treatment, in patients with good efficiency, CSF VIP recovered to normal level and the levels of plasma and CSF SS were significantly increased, while the level of plasma PP had no significant change. The results suggest that acupuncture might regulate the disturbances of metabolism of VIP and SS in CNS.

Constitutive activation of gene expression by thyroid hormone receptor results from reversal of p53-mediated repression

Thyroid hormone receptor (T3R) is a member of the steroid hormone receptor gene family of nuclear hormone receptors. In most cells T3R activates gene expression only in the presence of its ligand, L-triiodothyronine (T3). However, in certain cell types (e.g., GH4C1 cells) expression of T3R leads to hormone-independent constitutive activation. This activation by unliganded T3R occurs with a variety of gene promoters and appears to be independent of the binding of T3R to specific thyroid hormone response elements (TREs). Previous studies indicate that this constitutive activation results from the titration of an inhibitor of transcription. Since the tumor suppresser p53 is capable of repressing a wide variety of gene promoters, we considered the possibility that the inhibitor is p53. Evidence to support this comes from studies indicating that expression of p53 blocks T3R-mediated constitutive activation in GH4C1 cells. In contrast with hormone-independent activation by T3R, p53 had little or no effect on T3-dependent stimulation which requires TREs. In addition, p53 mutants which oligomerize with wild-type p53 and interfere with its function also increase promoter activity. This enhancement is of similar magnitude to but is not additive with the stimulation mediated by unliganded T3R, suggesting that they target the same factor. Since p53 mutants are known to target wild-type p53 in the cell, this suggests that T3R also interacts with p53 in vivo and that endogenous levels of p53 act to suppress promoter activity. Evidence supporting both functional and physical interactions of T3R and p53 in the cell is presented. The DNA binding domain (DBD) of T3R is important in mediating constitutive activation, and the receptor DBD appears to functionally interact with the N terminus of p53 in the cell. In vitro binding studies indicate that the T3R DBD is important for interaction of T3R with p53 and that this interaction is reduced by T3. These findings are consistent with the in vivo studies indicating that p53 blocks constitutive activation but not ligand-dependent stimulation. These studies provide insight into mechanisms by which unliganded nuclear hormone receptors can modulate gene expression and may provide an explanation for the mechanism of action of the v-erbA oncoprotein, a retroviral homolog of chicken T3R alpha.

Effect of acupuncture on vasoactive intestinal peptide in ischemic cerebrovascular diseases

BACKGROUND AND PURPOSE

Vasoactive intestinal peptide (VIP) appears to play an important role as a neurotransmitter or neuromediater in ischemic cerebrovascular diseases (ICVD). The effect of acupuncture, which is used in treatment of ICVD with good efficiency, on VIP has not been known. For finding the mechanism of acupuncture in treatment of ICVD and the effect of electro-acupuncture on VIP, the present study was performed.

MATERIALS AND METHODS

59 patients with acute ICVD were randomly divided into two groups. Electro-acupuncture and routine treatment were given in Group 1 (n = 29), and routine treatment was used alone in Group 2 (n = 30). The cerebrospinal fluid (CSF) and blood were taken before the beginning of treatment and after a course of treatment in both groups. The control group consisted of 38 cases of non-ICVD. VIP was measured by radioimmunoassay.

RESULTS

The level of CSF VIP in patients with acute ICVD was significantly lower than that in the controls, while the levels of plamsa VIP showed no significant difference between the ICVD and control groups, and the level of CSF VIP was not significantly correlated with the level of plasma VIP. After acupuncture treatment, the level of CSF VIP was increased and showed no significant difference as compared with the control group.

CONCLUSION

Acupuncture might alleviate the disturbance of metabolism of VIP in CNS.

[Measurement and clinical significance of inspiratory drive efficacy in patients with chronic obstructive pulmonary disease]

To study the relationship between VT/P0.1 and the function of inspiratory muscles, we performed the measurement of VT/P0.1 (inspiratory drive efficacy), MIP (maximal inspiratory mouth pressure) and MMIF (maximal midinspiratory flow) in 15 normal subjects and 60 patients with chronic obstructive pulmonary disease(COPD). The results indicated that VT/P0.1 decreased with the deterioration of COPD and it correlated highly and positively with MIP and MMIF. These suggest that VT/P0.1 can reflect the function of inspiratory muscles as well as MIP and MMIF can.

Molecular cloning of a new intermediate filament protein expressed by radial glia and demonstration of alternative splicing in a novel heptad repeat region located in the carboxy-terminal tail domain

In the present study we describe the molecular cloning of transitin, formerly named EAP-300. We show that transitin is an intermediate filament protein with a core domain most closely resembling nestin and tanabin. Transitin also contains a novel heptad amino acid repeat domain, comprising multiple leucine zipper repeats, located in its tail region. Based on these structural motifs we propose that a novel intermediate filament protein that is transiently expressed by radial glia during CNS development has been identified. We also show the existence of splice variants of transitin with splicing occurring in the novel heptad repeat domain to give rise to transitin isoforms that lack this heptad repeat. By in situ hybridization analysis we show that transitin mRNA is expressed by midline radial glial structures, by several axon commissures, and by Bergmann glia of the developing cerebelium. Based on the structural properties of the transitin protein, and expression of its mRNA, we suggest that transitin is a new member of the intermediate filament gene superfamily that is transiently expressed by radial glia.

Interaction of PKC and NOS in signal transduction of microvascular hyperpermeability

Our previous studies have shown that inflammatory mediators increase microvascular permeability through a phospholipase C-nitric oxide synthase (NOS)-guanylate cyclase cascade. The aim of this study is to delineate in more detail the signaling pathway leading to microvascular hyperpermeability. Endothelial cytosolic calcium and the apparent permeability coefficient of albumin (Pa) were measured in isolated and perfused coronary venules. Histamine stimulated a rapid increase in cytosolic calcium followed by a transient elevation in Pa. The NOS inhibitor NG-monomethyl-L-arginine (L-NMMA) and the guanosine 3',5'-cyclic monophosphate-dependent protein kinase G (PKG) inhibitor KT-5823 abolished the hyperpermeability but did not affect the calcium response to histamine. Similarly, the calcium ionophore ionomycin produced a calcium spike preceding venular hyperpermeability. Blockage of the NOS-PKG cascade inhibited the increase in Pa, whereas the endothelial calcium was still elevated on administration of ionomycin. Furthermore, the relationship between protein kinase C (PKC) and the calcium-NOS-PKG pathway in modulation of venular permeability was investigated. Stimulation of PKC with phorbol 12-myristate 13-acetate (PMA) dramatically increased basal Pa without significantly changing the cytosolic calcium level. The selective PKC inhibitor bisindolylmaleimide abolished the effect of PMA but did not alter the effect of histamines on Pa. In contrast, both L-NMMA and KT-5823 were able to greatly attenuate the increase in Pa caused by PMA. These results suggest that 1) elevation of endothelial cytosolic calcium is an early signaling event preceding nitric oxide (NO) synthesis in the transduction of endothelial hyperpermeability, and 2) activation of PKC may alter the endothelial barrier function partially through the modulation of NO production.

Establishment and characterization of cell lines derived from uterine malignant mixed Müllerian tumor

OBJECTIVE

We report the establishment and characterization of three new cell lines derived from uterine malignant mixed müllerian tumor (MMMT).

METHODS

Three uterine MMMT cell lines from primary tumors of Korean patients were cultured and the involved cell morphology, growth properties, DNA profiles, immunohistochemical properties, tumor-associated antigen secretion, and genetic alterations of related oncogenes and tumor suppressor genes were studied as well.

RESULTS

Three MMMT cell lines were successfully established including one homologous tumor SNU-539 and two heterologous tumors SNU-685 and SNU-1077. All lines showed substrate adherence and high viability and were proven by DNA fingerprinting analysis to be unique. Contamination by mycoplasma and bacteria was excluded. SNU-539 and SNU-1077 cells stained positively for both epithelial and mesenchymal antigens, while SNU-685 cells only stained positively for mesenchymal antigens. The level of secretion of tumor-associated antigens, CA125 and CEA, was shown to be undetectable in all three lines. One missense mutation from AAC to GAC at codon 239 of exon 7 in the p53 gene was identified in SNU-539.

CONCLUSIONS

These newly established and characterized permanent uterine MMMT cell lines might be regarded as valuable resources for a multitude of in vitro investigations, which should be used for clarifying the obscure histogenetic origin and understanding the biological behavior of this aggressive tumor.

[Relative contribution of ageing and menopause to the changes of lumbar bone density in 1,400 Beijing women]

OBJECTIVE

To study the pattern of bone mass changes in women's lumbar spine and obtain evidence to guide the prevention of postmenopausal osteoporosis.

METHOD

Bone mineral content (BMC) and bone mineral density (BMD) of lumbar 1-4 in 1 400 Beijing women aged 20-85, were measured by dual energy X-ray absorptiometry.

RESULTS

(1) Both BMC and BMD increased after age 20, reached the peak at the age of 30, and decreased significantly after the age of 50; (2) There was no significant change of BMC and BMD after the age of 25 in premenopausal women. Bone loss accelerated in the first 10 years after menopause. Women who experienced menopause early had lower bone mass. (3) The prevalence of osteoporosis in 1 121 postmenopausal women was 17.40%.

CONCLUSION

Significant bone mass loss of lumbar spine occurs during the first decade following menopause, which is the key period for preventing osteoporosis.

[HPLC determination of diltiazem in human serum and its pharmacokinetic parameters]

A simple and sensitive reversed-phase liquid chromatographic method has been developed and validated for the analysis of diltiazem in human serum and the study of pharmacokinetics of the drug in human body. Diltiazem and diazepam (internal standard) in serum were extracted with hexane-chloroform-isopropanol (60:40:5, V/V), and then measured by HPLC using a Spherisorb C18 column as stationary phase and a methanol-water triethylamine as mobile phase. Diltiazem was quantified by ultraviolet absorbance at 239 nm. The method proved to be linear in the clinical range of 15-300 microg/L with a regression coefficient of 0.9997. The lower limit of detection of diltiazem in serum was 3 microg/L. Intra-day and inter-day coefficients of variation of assay for diltiazem in serum were 3.5%-6.8% (n=7) and 6.2%-8.4% (n=5), respectively. The recoveries of diltiazem were 91%-104% for serum. The method has been used to determine diltiazem in serum samples from eight volunteers and provided data on the pharmacokinetics of the drug. The results inferred that diltiazem is absorbed rapidly and had a relatively short half-life time in healthy individuals. The data obtained was fitted with PKBP-N1 program on computer to study the pharmacokinetics. The results showed that the peak level in serum averaged 118.5 microg/L +/- 14.3 microg/L at 3.1 h +/- 0.4 h, and the areas under the drug concentration curves (AUC) was 793.1 microg x h/L +/- 83.1 microg x h/L.

Establishment and characterization of human ovarian carcinoma cell lines

Five human ovarian carcinoma cell lines cultured from primary and metastatic tumors of Korean patients were characterized. These lines were isolated from two papillary serous cystadenocarcinomas, two endometrioid carcinomas, and one malignant Brenner tumor. It was shown that the growth of these cell lines was stable when cultured after at least 20 passages. Population doubling times varied from 40 to 67 hr. All lines showed high viability and were proven by DNA fingerprinting analysis to be unique. Contamination by mycoplasma or bacteria was excluded. In two lines, SNU-8 and SNU-840, an elevated level of CA125 antigen secretion could be detected, whereas CEA was undetectable in all five lines. Four different mutations in functional and highly conserved regions of the p53 gene were identified in three of our five lines (60%), namely in SNU-119, SNU-251, and SNU-563. Included were two missense mutations, one in-frame 3-base-pair deletion, and one out-of-frame 1-base-pair deletion. It is interesting to note that one of these three lines, SNU-251, presented an additional simultaneous nonsense mutation of the BRCA1 gene and missense mutation of the hMLH1 gene. In its lacking both wild-type alleles of the BRCA1 gene, SNU-251 might serve as an unusual and important in vitro model for studies related to ovarian carcinoma and the BRCA1 gene. It is thus likely that the establishment and characterization of these permanent human ovarian carcinoma cell lines in continuous cultures can provide useful tools for in vitro studies related to human ovarian carcinomas.

Calpain regulation of cytoskeletal signaling complexes in von Willebrand factor-stimulated platelets. Distinct roles for glycoprotein Ib-V-IX and glycoprotein IIb-IIIa (integrin alphaIIbbeta3) in von Willebrand factor-induced signal transduction

The adhesion of platelets to sites of vascular injury is critically dependent on the binding of subendothelial bound von Willebrand factor (vWf) to the platelet surface glycoprotein complexes, GP Ib-V-IX and GP IIb-IIIa (integrin alphaIIbbeta3). There is growing evidence that the binding of vWf to these receptors is not only essential for stable platelet adhesion but is also important for the transduction of activation signals required for changes in platelet morphology, granule secretion, and platelet aggregation. In this study we have investigated signaling events induced by vWf binding to GP Ib-V-IX in both spreading and aggregated platelets. The adhesion of platelets to vWf resulted in dramatic actin filament reorganization, as assessed by immunofluorescence with fluorescein isothiocyanate-conjugated phalloidin, and the cytoskeletal recruitment of various structural proteins (talin and integrin alphaIIbbeta3) and signaling enzymes (pp60c-src, focal adhesion kinase (FAK), phosphatidylinositol 3-kinase (PI 3-kinase), and protein-tyrosine phosphatase (PTP)-1B). Time course experiments in both spreading and aggregated platelets revealed that talin, FAK, and PTP-1B were proteolyzed after translocation to the cytoskeleton. The proteolysis of these proteins was dependent on the presence of extracellular calcium and was specifically inhibited by pretreating platelets with the membrane-permeable calpain inhibitors calpeptin, E64d, and MDL 28,170, but not with the membrane-impermeable inhibitors leupeptin, E64, and calpastatin. The cytoskeletal translocation of signaling enzymes in vWf-stimulated platelets was abolished by pretreating platelets with an anti-GP Ib-V-IX antibody but was unaffected by blocking ligand binding to integrin alphaIIbbeta3. In contrast, calpain activation in vWf-stimulated platelets required ligand binding to both GP Ib-V-IX and integrin alphaIIbbeta3. The activation of calpain in both spreading and aggregated platelets resulted in a substantial decrease in the level of tyrosine phosphorylation of multiple platelet proteins and was associated with a 50-80% reduction in the amount of cytoskeletal associated talin, integrin alphaIIbbeta3, PI 3-kinase, FAK, pp60(c-)src, and PTP-1B. These studies suggest a potentially important role for calpain in regulating the formation and/or stability of cytoskeletal signaling complexes in vWf-stimulated platelets. Furthermore, they demonstrate distinct roles for GP Ib-V-IX and integrin alphaIIbbeta3 in vWf-induced signal transduction.