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T Sugino

Publications and source records attributed to T Sugino.

At least 55 records · Page 3Linked to original sources
PubMed1996

Cellular distribution of CD44 gene transcripts in colorectal carcinomas and in normal colonic mucosa.

AIM: To study the cellular distribution of CD44 mRNA transcripts in tissue sections of colorectal cancer and corresponding normal colonic mucosa in order to correlate the findings with information from immunohistochemical methods and previous data from analysis by reverse transcription-polymerase chain reaction (RT-PCR). METHODS: In situ hybridisation (ISH) analysis of CD44 standard (CD44s) and variant (CD44v) mRNA in cryostat sections of normal and neoplastic colonic mucosa with 35S-labelled riboprobes. Immunohistochemistry was performed on cryostat sections from the same patients using monoclonal antibodies directed against epitopes encoded by CD44 exon 1 (F.10.44.2), exon 5, (Hermes 3), exon 7 (23.6.1), and exon 11 (2F10). RESULTS: CD44s and CD44v transcripts were both strikingly increased in carcinomas compared with corresponding normal mucosa and the abundant CD44v transcripts in tumour tissues were localised exclusively in the cancer cells. CD44s transcripts were present in cancer, inflammatory and resident stromal cells, but the relative amount in carcinoma cells was greater. Immunohistochemical staining broadly paralleled these results, but some clumps of tumour cells showed clear heterogeneity with regard to CD44 protein content. There were also some scattered focal discrepancies in the quantity and distribution of mRNA transcripts and proteins, respectively. CONCLUSIONS: The ISH technique provides powerful independent corroboration of elevated CD44 gene expression and disproportionately high transcription of CD44v isoforms in carcinoma cells observed in earlier immunohistochemical and RT-PCR studies. It unequivocally localises the abnormally elevated gene transcription within the cancer cells and not in the surrounding inflammatory cells.

Antigens, Neoplasm↗
PubMed1996

Distribution of CD44 messenger RNA in archival paraffin wax embedded tumours and normal tissues viewed by in situ hybridisation.

Aims-We have previously demonstrated the abnormal localisation of expression of the CD44 gene in carcinoma cells in cryostat sections of fresh frozen tumour tissues, using radioactive in situ hybridisation (RISH). In order to facilitate further analysis of the expression of this gene in a wider range of neoplastic and non-neoplastic conditions, we have developed a technique which can visualise its low copy number transcripts in archival paraffin wax embedded specimens.Methods-(35)S labelled riboprobes complementary to transcripts from the standard (CD44s) and variant (CD44v) regions of the gene were used on paraffin wax embedded sections of tumours and corresponding normal tissues of the colon, breast and uterine cervix.Results-Elevated levels of signals for CD44s and CD44v transcripts were observed in carcinoma cells relative to their non-neoplastic counterparts in all tissues examined.Conclusion-This method permits easy access to material which can be selected for suitability, handled at room temperature without degradation and relied upon to show good histological detail. Comparison of the results with those on frozen tissues showed similar distributions of signals. Furthermore, the resolution and morphological detail was improved in paraffin wax sections.

Journal Article↗
PubMed1996

Progressive loss of CD44 gene expression in invasive bladder cancer.

This study investigated CD44 gene expression at both the RNA and protein level in well differentiated superficial and in deeply invasive bladder carcinomas. Proteins were studied by immunohistochemistry using antibodies against standard (CD44s) and variant (CD44v) isoforms. mRNA was analyzed by reverse transcriptase polymerase chain reaction/Southern blotting and in situ hybridization. Immunostaining with antibodies against CD44s and CD44v2, -5 and -6 (exons 7, 10, and 11, respectively) showed that carcinoma cells in all papillary tumors expressed strong signals throughout the epithelium but especially in the basal layer, which abuts on the stroma. However, invasive tumors, which are believed to originate mainly from flat urothelial tumors or, less frequently, from papillary carcinomas, progressively lost CD44 proteins as they penetrated deeper and became less differentiated. This change was paralleled at the mRNA level, by the gradual loss of expression of CD44s and CD44v transcripts in deeply invasive tumors until they were virtually undetectable. Conversely, papillary tumors contained multiple higher molecular weight transcripts, suggesting that the loss of CD44 proteins in the more aggressive tumors is due to a disturbance in transcription. This concept was confirmed by in situ hybridization studies with a probe showing that substantial variant CD44 mRNA is located in the urothelium in papillary carcinomas but is absent from deeply invasive carcinomas. These results indicate that initially there is a striking increase in CD44 gene expression in early bladder carcinomas, relative to normal urothelium, but that this diminishes as the tumors acquire a more aggressive phenotype.

Base Sequence↗
PubMed1996

Analysis of anomalous CD44 gene expression in human breast, bladder, and colon cancer and correlation of observed mRNA and protein isoforms.

Many studies have now demonstrated disorganized overexpression of the CD44 gene in various types of human malignant tumors, and this abnormality has emerged as an interesting candidate marker for early cancer diagnosis. The purpose of this work was to analyze and compare the patterns of transcription and translation of this gene in human breast (ZR75-1; MDAMB-435 clone 4A4) and colon (HT29) tumor cell lines and in tumors of the breast, bladder, and colon, with the aim of identifying the most suitable analyte for diagnostic purposes. Transcription was studied by reverse transcription-polymerase chain reaction using CD44-specific primers and probes complementary to exons in the standard (exons 3 to 5 and 16 to 18) and variably expressed regions of this gene (exons 7, 8, 10, 11, and 15). Translation was investigated by Western blot analysis and immunohistochemistry using monoclonal antibodies specific to the standard form of CD44 and to the products of the same variant exons. Southern blot hybridization analysis of the reverse transcription-polymerase chain reaction products showed a large number of CD44 transcripts in tumor cells. Direct comparison of these Southern blots with Western blots on matched tumor-cell-line extracts indicated that most of the diverse mRNA isoforms did not detectably translate into proteins. However, immunohistochemistry of normal and malignant breast (n = 17 and 23, respectively), bladder (n = 5 and 19), and colon (n = 19 and 19) tissue specimens showed increased staining of CD44 standard and CD44 variant proteins in the carcinoma cells. Combination of this information with the data from reverse transcription-polymerase chain reaction and Western blot analysis indicates that the overexpression at the protein level involves only a minority of the aberrant RNA transcripts. We conclude that the development of methods for the accurate quantitation of over-abundant CD44 RNA species in clinical samples offers the most promising approach to improved early diagnosis of malignancy using this new marker.

Antibodies, Monoclonal↗
PubMed1996

[Recurrence of a giant fusiform aneurysm after neck clipping: case report].

The patient was a 71-year-old female. On December 20, 1995, she suddenly developed a severe headache with vomiting and was transferred to our hospital. On admission, her conciousness level was 1-2 on the Japan Coma Scale, but there was no neurological deficit except for right oculomotor palsy. Computed tomography showed subarachnoid hemorrhage which had permeated the right lateral ventricle. On cerebral angiography, a giant fusiform aneurysm in the right internal carotid artery was recognized. During the emergency operation, neither neck clipping nor carotid reconstruction was possible because of the tight adhesion of the aneurysm to the peripheral tissue. On account of this, proximal clipping of the carotid artery with external carotid-middle cerebral artery anastomosis with saphenous vein graft was selected. This patient had had an episode of subarachnoid hemorrhage owing to rupture of the right internal carotid-posterior communicating artery aneurysm ten years earlier. At that time, the aneurysmal neck was clipped with a slight residual neck and she left the hospital on foot. Five days later, when the aneurysm was found to be completely thrombosed on CT scan, antiplatelet therapy was started. Although low density areas which corresponded to the regions fed by the right anterior choroidal artery were presented, re-rupture did not occur. Follow-up angiography showed that the aneurysm was completely thrombosed and that the right middle cerebral and the anterior cerebral artery blood was circulated via the vein graft. Among recurrent cases of aneurysm after neck clipping, it is unusual for a giant fusiform aneurysm to be recognized. The growth may have been caused by sclerotic change of the arterial wall. Oculomotor palsy may have delayed the detection of the recurrence of the aneurysm. When residual neck is presented on follow-up angiography, the next angiography should be carried out within at least three years. In this case, antiplatelet therapy was effective to prevent thromboembolism from the aneurysm.

Aged↗
PubMed1995

Abnormal retention of intron 9 in CD44 gene transcripts in human gastrointestinal tumors.

We have recently identified a new exon of the CD44 gene and demonstrated abnormal retention of a noncoding section, intron 9, in mRNA from bladder carcinomas. To analyze this further, the present study examined CD44 gene expression in cell lines from 14 esophageal, 3 colonic, and 4 breast carcinomas and in fresh samples from 20 colorectal carcinomas and corresponding normal colonic mucosa, using reverse transcriptase followed by the polymerase chain reaction (RT-PCR). This confirmed that there was abnormal assembly of several exons of the gene in cell lines and in tumor tissues from these organs. However, the most striking new finding was that intron 9 was present in RNA from 11 esophageal, 3 colon, and 1 breast carcinoma cell line, respectively. This was confirmed by RNase and DNase digestion analysis. Moreover, it was detected both in nuclear and cytoplasmic mRNA fractions, indicating that abnormal splicing of pre-mRNA occurs in cancer cells. The abnormal retention of intron 9 in CD44 gene transcripts was also demonstrated in tumor tissues from 16 (80%) of 20 patients with colon carcinoma, but there was no correlation with Dukes' stage. The biological significance of these observations is not yet understood. However, it is clear that, as with the abnormal expression pattern of CD44 variant exons, intron 9 retention is a good-candidate molecular diagnostic tool for colorectal carcinomas.

Base Sequence↗
PubMed1995

Non-invasive detection of bladder cancer by identification of abnormal CD44 proteins in exfoliated cancer cells in urine.

Aims-To investigate the expression of CD44 proteins in exfoliated urothelial cells and in tumour tissues from bladder cancer patients. A further objective was to evaluate the diagnostic potential of the changes observed in the expression of these proteins as a marker for non-invasive detection of bladder cancer.Methods-Naturally voided urine specimens were collected from 47 patients with bladder cancer or severe urothelial dysplasia (n=3) and from a control group of 43 people with no evidence of neoplastic disease. Exfoliated urothelial cells floating in the urine were pelleted by centrifugation and lysed, and their constituent proteins extracted. The pattern of expression of CD44 proteins in each sample was examined by western blot analysis using a monoclonal antibody, Hermes 3, which recognises an epitope on the polypeptide backbone of the CD44 protein. Immunohistochemical studies were performed on neoplastic (n=10) and normal (n=4) bladder tissue specimens which were snap frozen in liquid nitrogen before examination with antibodies to CD44 gene products (CD44s and CD44v6).Results-Western blot analysis revealed several high molecular weight CD44 isoforms > 160 kDa in urine cell lysates from 75% of patients with histologically confirmed bladder cancer and in two of the three patients with severe dysplasia. Such patterns were not detected in the urine cell pellets from any persons in the control group. Immunohistochemical studies of the tissue distribution of CD44s and CD44v6 showed that the differentiation and maturation of the epithelial cells in the normal bladder mucosa is accompanied by a decrease in CD44 protein expression. However, carcinoma cells overexpress standard and variant CD44 isoforms and continue to do so as they proceed through the thickened epithelial layer to the luminal surface and after they are shed into the urine.Conclusions-The abnormal expression of CD44 proteins in exfoliated cancer cells may be a useful marker for the noninvasive diagnosis of bladder cancer.

Journal Article↗
PubMed1995

[Infantile brainstem infarction due to vertebral artery fenestration: a case report].

The patient was a 10-year-old boy. He had a sudden onset of generalized tonic-clonic convulsion. On admission, he presented with mild disturbance of consciousness and right hemiparesis. The electroencephalogram showed diffuse spike and slow wave complex. Three days later, magnetic resonance imaging (MRI) showed high signal intensity areas in the left cerebellar hemisphere and pons. On cerebral angiograms, coiling of the bilateral carotid arteries, occlusion of the basilar artery at the distal site, and fenestration of the left vertebral artery at the atlanto-axis level were shown. According to these findings, the patient was diagnosed with brainstem and cerebellar infarction. On the follow-up angiograms, recanalization of the basilar artery on the right vertebral angiogram, occlusion of the left vertebral artery at the distal site of the posterior inferior cerebellar artery origin, and occlusion of one of the duplicated vertebral arteries were recognized. Fenestration of the vertebral artery is presented in about 1-2% at angiography and autopsy and the clinical significance is controversial. In this case, the fenestration may have played a role as an embolic source because there was no probable cause of the cerebral infarction, and the vascular occlusion and recanalization occurred near the distal site of the fenestration. These findings suggest the clinical significance of vertebral artery fenestration as an embolic source.

Brain Stem↗
PubMed1993

Sequential process of blood-borne lung metastases of spontaneous mammary carcinoma in C3H mice.

We examined the correlation between growth characteristics and the incidence of lung metastases of spontaneous mammary tumors in C3H mice. The growth pattern of the mammary tumors was composed of initial rapid growth, declining growth, and further exponential growth (re-growth). The "re-growth" was closely associated with loss of differentiation and progressive increase of the incidence of lung metastases. In addition, we observed the sequential process of blood-borne lung metastases. The findings involved (i) "passive" intravasation: carcinoma nests encased in newly formed endothelial cells are released into sinusoidal vessels within primary tumors; (ii) "mechanical" arrest and proliferation of multicellular tumor emboli in pulmonary arterioles; (iii) "active" extravasation: carcinoma cells rushed out to the lung parenchyma through the arteriolar walls ruptured by initial minimal penetration of carcinoma cells and intravascular pressure. The results indicate a stable progression in the natural history of C3H mouse mammary carcinomas characterized by growth characteristics, the incidence of lung metastases, and histological change generating a poorly differentiated clone which can successfully complete a sequential process of blood-borne lung metastasis.

Adenocarcinoma↗
PubMed1993

[Experimental acute lung injury in guinea pigs after aerosol challenge with sonicated Pseudomonas aeruginosa whole cells].

Acute hemorrhagic alveolitis was elicited in the lungs of guinea pigs by aerosol challenge with sonicated P. aeruginosa whole cells. Histological findings showed the severe inflammatory changes, which were characterized by the inflammatory infiltration of alveolar macrophages (AM), polymorphonuclear leukocytes (PMN) and eosinophils in the peribronchial and the alveolar space at 8 hours after the challenge. A marked increase of PMN as well as AM was noted in the bronchial alveolar lavage fluid (BALF) at 8 hours after the challenge and the increase of the numbers of AM and PMN in the BALF remained until 24 hours after challenge. The complement titer (CH50) and C3 component in the serum decreased at the early stage, and CH50 maintained low level and C3 component increased gradually. Polyethyleneglycol precipitation-complement consumption test (PEG-CC) of the BALF showed the existence of immune complexes formed in the airway after aerosol inhalation. These data suggest that the immune complexes of P. aeruginosa activate the complement system in the lungs, which is followed by the infiltration of inflammatory cells. Guinea pigs which were pretreated with cobra venom factor significantly reduced the extent of the inflammatory changes in the lungs. The results suggests that the complement system might act as an important factor of the acute lung injury in this model.

Administration, Inhalation↗
PubMed1992

Immunocytochemical demonstration of IGF-II immunoreactivity in human phaeochromocytoma and extra-adrenal abdominal paraganglioma.

Insulin-like growth factor (IGF)-II immunoreactivity was demonstrated in 14 adrenal glands, six retroperitoneal paraganglia, 18 phaeochromocytomas, and six extra-adrenal abdominal paragangliomas through the use of a monoclonal antibody against rat IGF-II which cross-reacts with human IGF-II. A subpopulation of parenchymal cells in normal adrenal medulla and in retroperitoneal paraganglia was positively immunolabelled. Eighteen cases with phaeochromocytoma including two malignant and four multiple endocrine neoplasias all contained numerous IGF-II-immunoreactive tumour cells. All six extra-adrenal abdominal paragangliomas contained numerous immunoreactive tumour cells. Almost all the other normal human adult tissues examined failed to immunolabel. These results indicate that IGF-II-like immunoreactivity is widely expressed in normal and neoplastic human paraganglionic tissues, although its biological significance in these tissues has not been determined.

Abdominal Neoplasms↗
PubMed1992

Temperature-sensitive cdc7 mutations of Saccharomyces cerevisiae are suppressed by the DBF4 gene, which is required for the G1/S cell cycle transition.

When present on a multicopy plasmid, a gene from a Saccharomyces cerevisiae genomic library suppresses the temperature-sensitive cdc7-1 mutation. The gene was identified as DBF4, which was previously isolated by complementation in dbf4-1 mutant cells and is required for the G1----S phase progression of the cell cycle. DBF4 has an open reading frame encoding 695 amino acid residues and the predicted molecular mass of the gene product is 80 kD. The suppression is allele-specific because a CDC7 deletion is not suppressed by DBF4. Suppression is mitosis-specific and the sporulation defect of cdc7 mutations is not suppressed by DBF4. Conversely, CDC7 on a multicopy plasmid suppresses the dbf4-1, -2, -3 and -4 mutations but not dbf4-5 and DBF4 deletion mutations. Furthermore, cdc7 mutations are incompatible with the temperature-sensitive dbf4 mutations. These results suggest that the CDC7 and DBF4 polypeptides interact directly or indirectly to permit initiation of yeast chromosome replication.

Alleles↗
PubMed1990

[Exfoliative materials in the skin of patients with exfoliation syndrome].

The iris and the skin of the lateral canthus of patients with exfoliation syndrome were studied by light and electron microscopy. The materials were surgically obtained from 9 patients of cataract and/or glaucoma associated with exfoliation syndrome. For the control study, we prepared the iris and the skin of 6 patients without exfoliation syndrome. In all 9 cases of exfoliation syndrome, exfoliative materials were observed in the pigment epithelium of the iris. In 3 of 9 cases, exfoliative materials were found in the dermis. In 6 other cases, microfibrils and immature forms of exfoliative materials were observed, but not typical forms. Neither in the iris nor in the skin of the control cases were exfoliative materials detected. Exfoliative materials in the dermis seen in the patients with exfoliation syndrome were morphologically similar to those in the iris. This is the first report of demonstration of exfoliative materials in the skin. These observations suggest that exfoliation syndrome may be a systemic degenerative disorder of the body.

Aged↗
PubMed1986

A new DNA-dependent ATPase which stimulates yeast DNA polymerase I and has DNA-unwinding activity.

Two forms of DNA-dependent ATPase activity were previously purified from the yeast Saccharomyces cerevisiae and characterized (Plevani, P., Badaracco, G., and Chang, L. M. S. (1980) J. Biol. Chem. 255, 4957-4963). Here, an additional DNA-dependent ATPase (ATPase III) has been purified from S. cerevisiae to near homogeneity. This ATPase differs from those described previously in its chromatographic properties, molecular weight, reaction properties and immunological relatedness. Its molecular weight is about 63,000 in the presence of sodium dodecyl sulfate. It hydrolyzes ATP to ADP and orthophosphate in the presence of DNA as an effector. In addition, yeast DNA polymerase I, which is a true DNA replicase of yeast, is stimulated severalfold by this ATPase. Neither yeast DNA polymerase II nor prokaryotic DNA polymerases are stimulated. This stimulation is intrinsic to the ATPase activity, since both activities copurified in the last four steps of purification, showed the same heat stability and showed dependence on and hydrolysis of ATP. The ATPase III preparation also contains a DNA-unwinding (DNA helicase) activity, which unwinds double-stranded DNA in the presence of ATP. In the S. cerevisiae radiation-sensitive mutant rad3, no significant ATPase III activity could be detected, suggesting that the RAD3 gene, which codes for a different polypeptide, regulates the expression of ATPase III activity.

Adenosine Triphosphatases↗