Amplification of the c-erbB-2 gene detected by FISH in gastric cancers

The amplification and overexpression of the c- erbB -2 gene are considered to be Implicated In the process of carcincogenesis of a variety of human tumors. The amplification and overexpression of c- erbB -2 were investigated in 48 surgically resected human gastric cancers by means of fluorescence In situ hybridization and immunohistochemistry. DNA ploidy was determined by flow cytometry. The c- erbB -2 amplification was demonstrated as a cluster of signals, suggesting homogeneously staining region (HSR), in three tumors (6.3%) accompanied by the overexpression of its protein. Such overexpression was detected In another tumor without amplification of the c- erbB -2 gene. All tumors with amplification and overexpression of c- erbB -2 were differentiated adenocarcinoma histologically, but only 10.3 and 13.8% of differentiated carcinomas showed amplification and over-expression of the c- erbB -2 gene, respectively. There was no relationship between the amplification and overexpression of c- erbB -2 and the depth of tumor invaslon and lymph node Involvement. Three of four cases with overexpression of c- erbB -2 were classified Into DNA aneupldd tumor.     

p53 and Ki-67 immunoreactivity and nuclear morphometry of 'carcinoma-in-adenoma' and adenoma of the gall-bladder

Twenty lntramucosal tumors of ‘carclnomaln-adenoma’ and 43 ademas (39 pylorlc gland type, 4 Intestinal type) of the gall-bladder were studied to establish more precise histo-logical criteria of carcinoma or adenoma In cases of ‘carcinoma In pyforic gland type adenoma’, to compare carcinoma In adenoma with pure, that Is, without adenomatous components, carcinoma, and to confirm the benign nature of spin-dle cell fd in the adenomas. Ki-67 and p53 immunostaining and nuclear morphomety were used. Eight pure intramucessl cancers were used as controls. The formalin-fixed, paraffln+mbedded sections were stained with p53 and Ki-67 antibodies. Splndle cell foci were observed only In the adenoma area of the pyloric gland type, wlth a frequency of 23% In 39 adenomas, and of 45% in 20 tumors of carclnoma-lrradenoma. Ki-67 staining was negative in 129 of 130 spin-die cell foci examlned, regardless of their size, and positive in only one focus (550 pm in size, Ki-67 Index 0.2%). All of the spindle cell foci were negative for p53 stain. The Ki-67 positive index was 36.6 ± 5.6% In the 8 pure carcinomas, and 12.5 ± 1.9% in the cancer areas of 16 tumors with carcinoma-in-adenoma, while it was 7.9 ± 1.7% in the adenoma areas of 16 tumors with carcinoma-in-adenoma and 4.9 ± 0.5% in the 32 pure pyloric gland adenomas. The p53-protein over-expression was found in seven of eight pure intramucosal cancers, and in one of 16 cancer components of carclnoma-in-adenoma. However, it was not found in any of 16 adenoma components of carcinoma-in-adenoma, and 35 adenomas. Cells of the cancer tissue of carcinoma-In-adenoma showed a significantly larger nuclear area and a larger nuclear minor axis than those of the pyloric gland type adenomas, as well as other architectural and cytologic abnormalities differing from the features of adenomas. These results suggest that clustered spindle cells do not indmte a malignant transformation of adenoma cells and that carcinomas in carcinoma-in-adenoma are dtfferent from pylorlc gland type adenomas In terms of morphology and proliferative activity. Moreover, the results of the present study indicate that carcinomas In carcinoma-ln-adenoma are lower In malignancy than pure carcinomas, and that their genetic abnormaltty may differ from that of pure carcinomas.     

Possible role of hepatocyte growth factor in regeneration of human peritoneal mesothelial cells

Human peritoneal mesothelial cells (HPMCs) play an important role in peritoneal functions. During long term peritoneal dialysis, it has been reported that HPMCs are damaged by high glucose solution via the signal of transforming growth factor (TGF)-beta1 produced by HPMCs. In this study, we focused on the effect of hepatocyte growth factor (HGF), known as an anti-fibrotic and anti-TGF-beta1 agent, on HPMCs damaged by high glucose solution. HPMCs were isolated from specimens of the omentum from nonuremic patients after informed consent had been obtained. After confirming adhesion for 6 hours, 100 microL of DMEM with 0.5%FCS were added at different concentrations (D-glucose; 6, 30 mM) with or without HGF (10, 30, 100 ng/mL) for 48 hours. We examined the effects of a high concentration of glucose and then focused on following four critical points: 1) the production of HGF from HPMCs exposed to a high concentration of glucose, 2) the expression of c-Met on HPMCs, 3) the viability of those cells, and 4) matrix metalloproteinase-2 (MMP-2) and tissue inhibitors of metalloproteinase-2 (TIMP-2). The following significant changes are described herein: high glucose solution and TGF-beta1 i) decreased HGF production from HPMCs and ii) up-regulated expression of c-Met on HPMCs, and addition of HGF iii) restored viability of HPMCs damaged by glucose, iv) suppressed TGF-beta1 production by HGF, and v) induced up-regulation of MMP-2 and decreased TIMP-2 production by HPMCs. Levels of HGF decreased by high concentrations of glucose in the peritoneal cavity may induce the loss of HPMCs and thereby result in peritoneal fibrosis. These results suggest that HGF is an effective agent in the regeneration of peritoneal membrane damaged by high glucose solution.     

Modulation of myocardial reactive hyperemia

Pflügers Archiv - European Journal of Physiology -     

Distinct hemagglutinin and neuraminidase epitopes involved in antigenic variation of recent human parainfluenza virus type 2 isolates.

A panel of fourteen neutralizing anti-HN monoclonal antibodies (mAbs) to the prototype Greer strain of human parainfluenza virus type 2 (PI2) was used to determine the extent of antigenic variation in recent virus isolates. Competitive binding analysis with the mAbs indicated the presence of at least five distinct antigenic sites (I to V) on the HN glycoprotein molecule. MAbs recognizing different antigenic sites were found to be associated with the hemagglutinin (sites I, IV and V), hemagglutinin and neuraminidase (site II), or neuraminidase (site III) activities. The location of two distinct epitopes identifying the neuraminidase sites (II and III) was further verified from the generation of escape mutants. Antibodies directed to sites I and III failed to show any detectable binding or neutralizing activity against a number of natural PI2 virus isolates collected in Texas between 1986 and 1987. Interestingly, these natural variants, unlike the prototype virus, did not show any detectable neuraminidase activity with fetuin as a substrate and the enzyme activity was only detected with N-acetylneuramin-lactose as an alternative substrate. Despite the observed variation in the antigenic sites, primary infection with the prototype virus or the natural variants generated a protective immune response against challenge infection with the other virus strains.     

Molecular cloning and sequence analysis of the fusion glycoprotein gene of human parainfluenza virus type 2

A cDNA clone containing a 2.0-kb insert was identified as the human parainfluenza virus type 2 (PI2) fusion glycoprotein gene by hybridizing with a viral RNA probe and a synthetic oligonucleotide derived from a conserved sequence found in other paramyxovirus fusion protein genes. The complete nucleotide sequence of the glycoprotein gene was determined by the dideoxynucleotide sequencing procedure and found to contain a single, large open reading frame encoding a protein of 551 amino acids with a calculated molecular weight of 59,664. Comparison of the P12 fusion protein with those of other paramyxoviruses indicated similarities in overall length, N-terminal signal peptide sequence (amino acids 7 to 25), C-terminal membrane-spanning region (amino acids 486 to 513), and a highly conserved fusion sequence region at the N-terminus of the F1 subunit (amino acids 107 to 132).     

Alterations in Nonspecific Cross-reacting Antigen Localization during Cell Culture

Nonspecific cross reacting antigen (NCA), a constituent of the carcinoembryonic antigen family, was localized ultra-structurally in a human lung adenocarcinoma cell line, PC 9. NCA was distributed predominantly on the plasma membrane in the early phases of cell culture. Deletion of fetal bovine serum (FBS) from the culture medium suppressed cell division without significantly altering cell viability, and induced a dramatic but reversible change in NCA localization. Under these conditions, NCA was localized to membrane degradation products within cytoplasmic vesicles and vacuoles. Acid phosphatase activity was also present in some of these intracellular structures. Similar changes in NCA localization were seen in cells cultured with FBS at day 6 when the cells reached a plateau stage of growth. These findings strongly suggest that plasma membrane degradation is accelerated by the cessation of cell growth. Cytoplasmic reactivity for NCA in cancer cells may therefore reflect degradation of plasma membrane-associated NCA and may not necessarily be correlated with increased systhesis of this glycoprotein. Acta Pathol Jpn 39: 772 778, 1989.