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M Tsutsumi

Publications and source records attributed to M Tsutsumi.

At least 37 records · Page 2Linked to original sources
PubMed2001

Increased susceptibility of poly(ADP-ribose) polymerase-1 knockout mice to nitrosamine carcinogenicity.

The involvement of poly(ADP-ribose) polymerase-1 (Parp-1), one of the poly(ADP-ribose) polymerase family proteins, in genomic stability, DNA repair and cell death triggered by DNA damage has been well documented. However, the potential role of Parp-1 in carcinogenesis has not been well evaluated. In this study the carcinogenic activity of N:-nitrosobis(2-hydroxypropyl)amine (BHP) was studied in Parp-1(-/-) mice, generated by disrupting P:arp-1 gene exon 1. Parp-1(-/-) and Parp-1(+/+) male mice received 0, 250 and 500 p.p.m. BHP in their drinking water for 20 weeks and were then killed. The percentage of animals bearing hemangiomas and hemangiosarcomas in the liver and numbers of tumors per mouse were markedly higher in the Parp-1(-/-) groups given 250 or 500 p.p.m. BHP than in their Parp-1(+/+) counterparts. Hemangiosarcomas developed only in Parp-1(-/-) mice. In the lung the numbers of adenomas per mouse were increased in Parp-1(-/-) mice given BHP at 250 and 500 p.p.m. (P < 0.01) compared with the Parp-1(+/+) case. The results show that susceptibility to BHP is significantly elevated in Parp-1(-/-) mice, thus providing direct evidence that Parp-1 is relevant to carcinogenesis.

Adenocarcinoma↗
PubMed2001

FHIT alterations in lung adenocarcinomas induced by N-nitrosobis(2-hydroxypropyl)amine in rats.

Alteration of the FHIT gene was investigated in lung adenocarcinomas induced by N-nitrosobis(2-hydroxypropyl) amine (BHP) in male Wistar rats. Animals at 6 weeks of age were given 2000 p.p.m. of BHP in drinking water for 12 weeks, then maintained without further treatment until killed at the end of week 25. A total of 25 lung adenocarcinomas were obtained and total RNAs were extracted from each for assessment of aberrant transcription of the FHIT gene by reverse transcription (RT)-polymerase chain reaction (PCR) analysis. Aberrant transcripts were detected in 15 adenocarcinomas (60%) as absence in the regions of nucleotides (nt) -9 to 279, -98 to 279, -98 to 348 or -98 to 447. Genomic DNAs were also extracted from all 25 adenocarcinomas and exons 5-9 were examined for mutations, using PCR-single strand conformation polymorphism (SSCP) analysis and sequencing. A mutation was detected in only one adenocarcinoma (4%), an ACC to ATC (Thr to IIe) transition at codon 76. Southern blot analysis of eight tumors did not show any evidence of gross rearrangement or deletion of the FHIT gene. Western blot analysis revealed reduced expression of Fhit protein in six out of 10 adenocarcinomas (60%). These results suggest that alteration of the FHIT gene may be involved in the development of lung adenocarcinomas induced by BHP in rats.

Acid Anhydride Hydrolases↗
PubMed2001

Alcohol biomarkers: clinical significance and biochemical basis.

This article represents the proceedings of a symposium at the 2000 ISBRA Meeting in Yokohama, Japan. The chairs were Raj Lakshman and Mikihiro Tsutsumi. The presentations were (1) Sialic acid index of apolipoprotein J: A new marker for chronic alcohol consumption, by P. Ghosh and M. R. Lakshman; (2) Microheterogeneity of serum glycoproteins in alcoholics, by M. Tsutsumi and S. Takase; (3) Probing protein-ethanol adducts with combinatorial peptide libraries displayed by filamentous phage, by H. Anni, O. Nikolaeva, and Y. Israel Y; (4) Carbohydrate-deficient transferrin as a marker for heavy alcohol use: What have we learned; Where do we go from here, by R. F. Anton; (5) Sensitivity and specificity of carbohydrate-deficient transferrin in drinking experiments and different patient groups, by O. M. Lesch; (6), Transferrin variants interfere with the measurement of carbohydrate-deficient transferrin, by A. Helender, G. Eriksson, and J-O. Jeppson; and (7) Chronic ethanol on protein trafficking in liver, by P. Marmillot, M. N. Rao, and M. R. Lakshman.

Alcoholism↗
PubMed2001

Study of cytochrome P4502E1 mRNA level of mononuclear cells in patients with alcoholic liver disease.

BACKGROUND: Cytochrome P-4502E1 (CYP2E1) is an important enzyme because of its unique ability to convert many substrates to cytotoxins. The increased production of reactive intermediates by elevated enzyme concentrations leads to various pathological conditions. Therefore, it is important to detect induced CYP2E1 levels in alcoholic individuals to avoid xenobiotic-promoted liver injury. In the present investigation, we detected CYP2E1 mRNA levels of mononuclear cells obtained from 10 ml of blood by using competitive polymerase chain reaction (PCR) method. METHODS: Mononuclear cells were obtained from healthy individuals who did and did not drink habitually and patients with alcoholic liver disease (ALD). Complementary DNA synthesis was performed with RNA obtained from mononuclear cells by reverse transcription-PCR. Competitive PCR of CYP2E1 was performed with the sense (5'-CTGCAACGTCATA-GCCGACA-3') and antisense (5'-TCCATTTCCACGAGCAGGCA-3') primer and competitor DNA. Competitive PCR of beta-actin also was performed. Electrophoresis was scanned, and each band was digitized. The concentration of CYP2E1 and beta-actin mRNA was calculated from the ratio of competitor DNA. RESULTS: In healthy individuals who did and did not drink habitually, CYP2E1 mRNA levels were 103.3 copies/microl RNA and 101.7 copies/microl RNA, respectively. In actively drinking patients with ALD, CYP2E1 mRNA levels were 103.5 copies/microl RNA, but those levels decreased to 101.7 copies/microl RNA after 4 days of abstinence. No significant difference was observed in CYP2E1 mRNA levels between alcoholic fibrosis and cirrhosis. As control, we measured beta-actin mRNA levels in mononuclear cells in all samples. The mean value of beta-actin mRNA was 104.3 copies/microl RNA in all cases, which included patients with ALD. CONCLUSIONS: The results demonstrated that it is possible to measure the CYP2E1 mRNA levels of mononuclear cells in a 10 ml blood sample. The CYP2E1 mRNA level in mononuclear cells increases during drinking and decreases in abstinence for a short period of 3 to 4 days. It is concluded that CYP2E1 mRNA level may be used as an effective marker for alcoholic intake.

Actins↗
PubMed2001

Alterations of the transforming growth factor-beta signaling pathway in hepatocellular carcinomas induced endogenously and exogenously in rats.

To elucidate involvement of the transforming growth factor-beta (TGF-beta) signaling pathway in endogenous and exogenous liver carcinogenesis, we investigated mutations of TGF-beta receptor type II (TGF-betaRII), Smad2 and Smad4 genes, and expression of TGF-betaRII in hepatocellular carcinomas (HCCs) induced by a choline-deficient L-amino acid-defined (CDAA) diet and by N-nitrosodiethylamine (DEN). Male Fischer 344 rats received a CDAA diet continuously and HCCs were sampled after 75 weeks. Administration of DEN was followed by partial hepatectomy (PH), with colchicine to induce cell cycle disturbance and a selection pressure regimen, HCCs being obtained after 42 weeks. Total RNAs were extracted from individual HCCs and mutations in TGF-betaRII, Smad2 and Smad4 were investigated by reverse transcription (RT)-polymerase chain reaction (PCR)-restriction-single-strand conformation polymorphism (SSCP) analysis followed by sequencing analysis. Mutations of Smad2 were detected in 2 out of 12 HCCs (16.7%) induced by the CDAA diet, a GGT-to-GGC transition (Gly to Gly) at codon 30 and a TCT-to-GCT (Ser to Ala) transversion at codon 118, without any TGF-betaRII or Smad4 alterations. No mutations of TGF-betaRII, Smad2 and Smad4 were encountered in eleven HCCs induced by the exogenous carcinogen. Semi-quantitative RT-PCR revealed reduced expression of TGF-betaRII in 2 HCCs (16.7%) without Smad2 mutations out of 12 HCCs induced by the CDAA diet and none of 11 induced by DEN. These results suggest that the TGF-beta signaling pathway may be disturbed in endogenous liver carcinogenesis in rats.

Alkylating Agents↗
PubMed2001

Interleukin-15 expression is associated with malignant potential in colon cancer cells.

Interleukin 15 (IL-15 mRNA expression was detected in human colorectal cancer cells (Colo320, WiDr, TCO and DLD1) by the reverse transcriptase-polymerase chain reaction (RT-PCR). Only Colo320 and WiDr cells secreted IL-15 culture medium. With IL-15 treatment, all cell lines grew at a rate of 120-180% of that of nontreated cells. A binding assay with (125)I-labeled IL-15 showed binding activity to IL-15 in Colo320 (K(d): 0.098 nM) cells. IL-15 also reversed the growth inhibition caused by serum starvation in Colo320 cells. IL-15-induced cell growth in regular and serum-free media was abrogated by anti-IL-15 antibody treatment in Colo320 cells. Moreover, IL-15 treatment reduced doxorubicin-induced cytostasis and cytolysis in Colo320 cells by 50%. The invasion capacity of IL-15-treated Colo320 cells was 5.3 times that of untreated cells. Immunoblotting showed that IL-15-treated Colo320 cells exhibited downregulation of p21Waf1 and Bax, and upregulation of Bcl-2, phospho-AKT, MMP9/MMP2, and VEGF. Finally, immunostaining of human colon cancer revealed that 33 (70%) of 47 Dukes' C cases showed IL-15 expression in cancer cells, whereas only 16% of Dukes' B cases did (p < 0.0001). IL-15 may play important roles in cell proliferation, invasion, and metastasis of human colorectal cancer.

Adenocarcinoma↗
PubMed2001

Fourth ventricular meningioma in an adult--case report.

A 72-year-old female presented with an intra-fourth ventricular meningioma manifesting as truncal ataxia. Computed tomography (CT) showed a slightly high-density, well-demarcated, and homogeneously enhanced mass located in the fourth ventricle and extending to the right lateral recess. T2-weighted magnetic resonance (MR) imaging revealed a peritumoral high-intensity band without dural tail sign. Bilateral vertebral angiography revealed faint tumor staining supplied from the choroidal branches of the posterior inferior cerebellar arteries. The mass was totally resected via a suboccipital approach. CT, T2-weighted MR imaging, and vertebral angiography are informative for the preoperative diagnosis of fourth ventricular meningioma.

Aged↗
PubMed2001

Intracranial meningeal malignant fibrous histiocytoma mimicking parasagittal meningioma--case report.

A 69-year-old female presented with a rare intracranial meningeal malignant fibrous histiocytoma (MFH). The neuroimaging appearance of this tumor was very similar to parasagittal meningioma. The tumor was grossly totally removed, and local irradiation of 50 Gy was performed. The histological diagnosis was MFH. The patient recovered from the preoperative deficits, and no recurrence was observed by 27 months after surgery.

Aged↗
PubMed2001

Heparan sulfate enhances invasion by human colon carcinoma cell lines through expression of CD44 variant exon 3.

CD44 variant exon (CD44v) 3 is a heparan sulfate-binding isoform of CD44. The role of CD44v3 in invasion and metastasis associated with heparan sulfate in colon cancer cell lines and cases of colon cancer was examined. Expression of CD44v3 mRNA and protein was observed in five of six human colorectal cancer cell lines. Colo320 and WiDr cells expressed CD44v3 at high levels. Heparan sulfate treatment increased the invasive activity of Colo320 and WiDr cells to rates 14.3 and 12.6 times higher, respectively, than that of untreated cells. However, heparan sulfate treatment did not affect cell growth. Repression of CD44v3 protein production by antisense S-oligodeoxynucleotide treatment reduced the binding affinities and capacities for heparan sulfate by Colo320 and WiDr cells in comparison with that of control cells, and it also reduced the invasiveness of both cell lines to one-fifth that of control cells. In heparan sulfate-treated Colo320 cells, the levels of CD44v3 protein in the Triton X-100-insoluble fraction and moesin-precipitated fraction were increased, suggesting that heparan sulfate treatment facilitates association of CD44 molecules with the cytoskeleton. Immunohistochemical analysis showed CD44v3 to be expressed in 21 of 37 (57%) colorectal cancer cases. Positive CD44v3 expression was associated with more advanced pathological stage and poorer prognosis than negative CD44v3 expression. These data support a role for CD44v3 in invasion and metastasis by colorectal carcinoma cells.

Antigens, CD↗
PubMed2000

Mutations of adenomatous polyposis coli and beta-catenin genes during progression of lung tumors induced by N-nitrosobis(2-hydroxypropyl)amine in rats.

In the present study, we investigated mutations of the adenomatous polyposis coli (APC) and beta-catenin genes to clarify possible molecular mechanisms underlying development of lung tumors induced by N-nitrosobis(2-hydroxypropyl)amine (BHP) in rats. Male Wistar rats, 6 weeks of age, were given 2000 ppm BHP in drinking water for 12 weeks and then maintained without further treatment until sacrifice at week 25 DNA was extracted from paraffin-embedded tissues, and PCR-single-strand conformation polymorphism analysis, followed by nucleotide sequencing, was performed. No APC mutations were detected in 17 hyperplasias, but 2 of 15 adenomas (13.3%) and 8 of 20 adenocarcinomas (40.0%) showed changes within exon 1 to the mutation cluster region in exon 15. For beta-catenin, no mutations were detected in 17 hyperplasias, but 3 of 15 adenomas (20.0%) and 5 of 20 adenocarcinomas (25.0%) had alterations within or flanking codons corresponding to important phosphorylation sites. Immunohistochemical staining showed beta-catenin protein localized in the cell membranes in the surrounding normal-appearing lung and 216 hyperplasias and localized mainly in the cytoplasm and/or nucleus in 10 of 37 adenomas (27.0%) and 21 of 40 adenocarcinomas (52.5%). These results suggest that the APC-beta-catenin-T-cell factor signaling pathway is involved in the acquisition of growth advantage from adenomas to adenocarcinomas in BHP-induced rat lung carcinogenesis.

Adenocarcinoma↗
PubMed2000

Absence of p16, p21 and p53 gene alterations in hepatocellular carcinomas induced by N-nitrosodiethylamine or a choline-deficient L-amino acid-defined diet in rats.

To clarify the involvement of tumor suppressor genes in exogenous and endogenous liver carcinogenesis, alterations of p16, p21 and p53 in hepatocellular carcinomas (HCCs) induced by N-nitrosodiethylamine (DEN) and a choline deficient L-amino acid-defined (CDAA) diet in rats were investigated. Male Fischer 344 rats received DEN at 6-week of age followed by partial hepatectomy (PH), with colchicine to induce cell cycle disturbance, and a selection pressure regimen. Sacrifice was after 42 weeks. Other animals continuously received a CDAA diet for 75 weeks and were then killed. Eleven and 15 HCCs were obtained, respectively. Total RNA was extracted from and cDNA was synthesized with reverse transcriptase to allow investigation of mutations in p16, p21 and p53 by polymerase chain reaction single strand conformation polymorphism (PCR-SSCP) analysis. Expression of p16 and p21 mRNA was also analyzed by reverse transcription (RT)-PCR. The results showed no mutations or deletions of p16, p21 and p53 in any of the HCCs induced by DEN or CDAA. Loss or decrease of p16 and p21 expression were also not found, suggesting that p16, p21 and p53 alteration may not be necessary for either exogenous or endogenous liver carcinogenesis in rats.

Animals↗
PubMed2000

Increased expression of cyclooxygenase-2 protein in rat lung tumors induced by N-nitrosobis(2-hydroxypropyl)amine.

Expression of cyclooxygenase (COX)-2 protein in preneoplastic and neoplastic lung lesions induced by the administration of 2000 ppm of N-nitrosobis(2-hydroxypropyl)amine (BHP) in the drinking water to Wistar male rats, was examined immunohistochemically. The majority of alveolar/bronchiolar adenomas (ADs) and all adenocarcinomas (ADCs) examined, stained positive or strongly positive for COX-2. In contrast, only a minority of alveolar/bronchiolar hyperplasias demonstrated immunoreactivity and half of the squamous cell carcinomas examined, were only weakly positive. Western blotting analysis also revealed expression of COX-2 protein in the resected ADs and ADCs. These results clearly indicate up-regulated expression of COX-2 in lung neoplastic lesions, particularly ADs and ADCs, induced by BHP in rats.

Adenocarcinoma, Bronchiolo-Alveolar↗
PubMed2000

Mutations of the Smad2 and Smad4 genes in lung adenocarcinomas induced by N-nitrosobis(2-hydroxypropyl)amine in rats.

Mutations of the Smad2 and Smad4 genes, identified as mediators of the transforming growth factor-beta pathway, were investigated in lung adenocarcinomas induced by N-nitrosobis(2-hydroxypropyl)amine (BHP) in rats. Male Wistar rats, 6 wk old, were given 2000 ppm BHP in their drinking water for 12 wk and maintained without additional treatment until killed at week 25. Total RNA was extracted from 12 adenocarcinomas, and mutations in Smad2 and Smad4 were investigated by reverse transcription-polymerase chain reaction restriction single-strand conformation polymorphism analysis followed by sequencing analysis. In Smad2, single adenocarcinomas showed a GGC to GAC (Gly to Asp) transition at codon 100 and an AAG to GAG (Lys to Glu) transition at codon 383. In Smad4, one adenocarcinoma exhibited a TTC to CTC (Phe to Leu) transition at codon 214. These results suggest that mutations of Smad2 and Smad4 may play roles in a limited fraction of lung adenocarcinomas induced by BHP in rats.

Adenocarcinoma↗
PubMed2000

Precancerous conditions for pancreatic cancer.

Precancerous conditions for ductal adenocarcinoma of the pancreas in hamsters and human beings are discussed. In hamsters, ductal adenocarcinomas induced by nitrosamines are of nonmucin-hypersecreting tubular or papillary tumor types, and genetic alterations resembling these types are found in their human counterparts. Ductal lesions develop step-by-step from hyperplasias to carcinomas, and atypical ductal cell hyperplasias may be precancerous. In humans, ductal lesions, hyperplasias, or dysplasias, with or without mucin hypersecretion, are possible preneoplastic conditions. Genetic or phenotypic markers to determine their likelihood of progressing to pancreatic duct adenocarcinomas are a high priority for future research.

Adenocarcinoma↗
PubMed2000

The response of Parp knockout mice against DNA damaging agents.

Gene-disruption studies involving poly(ADP-ribose) polymerase (Parp) have identified the various roles of Parp in cellular responses to DNA damage. The partial rescue of V[D]J recombination process in SCID/Parp(-/-) double mutant mice indicates the participation of Parp in the repair of DNA strand break. Parp(-/-) mice are more sensitive to the lethal effects of alkylating agents. Parp is also thought to be involved in base-excision repair after DNA damage caused by alkylating agents. On the other hand, resistance of Parp(-/-) mice to DNA damage induced by reactive oxygen species implicates the contribution of Parp to cell death through NAD depletion. Parp(-/-) mice with two different genetic backgrounds also show enhanced sensitivity to the lethal effects of gamma-irradiation. Parp(-/-) mice show more severe villous atrophy of the small intestine compared to the wild-type counterpart in a genetic background of 129Sv/C57BL6. Other forms of enhanced tissue damage have been identified in Parp(-/-) mice with a genetic background of 129Sv/ICR. For example, Parp(-/-) mice exhibit extensive hemorrhage in the glandular stomach and other tissues, such as the testes, after gamma-irradiation. Severe myelosuppression is also observed in both Parp(+/+) and Parp(-/-) mice, but Parp(+/+) mice show extensive extramedullary hematopoiesis in the spleen during the recovery phase of post-irradiation, whereas the spleen of Parp(-/-) mice exhibits severe atrophy with no extramedullary hematopoiesis. The absence of extramedullary hematopoiesis in the spleen is probably the underlying mechanism of hemorrhagic tendency in various tissues of Parp(-/-) mice. These findings suggest that loss of Parp activity could contribute to post-irradiation tissue hemorrhage.

Alkylating Agents↗
PubMed2000

Development and characterization of a photoautotrophic cell line of pak-bung hairy roots.

A cell line of photoautotrophic pak-bung hairy roots was established from photomixotrophic ones by acclimation cultivations with a stepwise change of sucrose concentration in a medium with 3.0% CO2-enriched air supplied under continuous light irradiation. The derived photoautotrophic hairy roots had high chlorophyll content and activity of 1,5-ribulose-bisphosphate carboxylase/oxygenase, the values of which were 4.1- and 2.0-fold more than those of the parent photomixotroph, respectively. Electron microscopic observation revealed that the photoautotrophic hairy root cells possessed well-developed chloroplasts. The activities of ascorbate peroxidase and guaiacoal peroxidase found in the hairy roots were comparable to those found in the leaves and roots of parent plants of pak-bung, respectively. The elongation rate of growing points of the hairy roots was maximum at 5.0% CO2 concentration in gas phase and an incident light intensity of 10 W/m2 under the photoautotrophic conditions examined. Although light was indispensable for ensuring photoautotrophy of the hairy roots, it was found that exposure of the roots to strong light resulted in the reduction in the number of viable growing points governing the overall growth rate of the hairy roots.

Journal Article↗
PubMed2000

Age and organ dependent spontaneous generation of nuclear 8-hydroxydeoxyguanosine in male Fischer 344 rats.

8-Hydroxydeoxyguanosine (8-OHdG) is a major oxidative DNA adduct playing roles in senescence, carcinogenesis and various disease processes. High-performance liquid chromatography with an electrochemical detection (HPLC-ECD) method has been widely used to assess organ levels of 8-OHdG, and a recently introduced immunohistochemical approach has made it possible to clarify intra-organ localization. In the present study, these methods were employed to reveal age-dependent changes in nuclear 8-OHdG within various tissues of male Fischer 344 rats between 18 fetal days and 104 weeks of age. 8-OHdG was detected in the nuclei of cerebellar small granule and small cortical cells, cerebral nerve cells, and choroid plexus epithelia of the brain and ependymal cells of the spinal cord; parenchymal cells in the anterior lobe of the pituitary and adrenal glands (mainly cortex); bronchial epithelium of the lung; intra-hepatic bile duct, pancreatic duct, glandular gastric and intestinal epithelial cells; renal tubular epithelial cells (mainly medulla); and spermatogonia and spermatocytes of the testis and seminal vesicle epithelia. The nuclear 8-OHdG levels were high (more than two lesions per 10(6) deoxyguanosines) from 7 days to 104 weeks of age in the brain, 3 to 6 weeks in the adrenal gland, 6 to 104 weeks in the lung, and 3 to 52 weeks in the testis. In the other organs, the nuclear 8-OHdG levels remained low throughout. These findings provide a basis for research dealing with oxidative stress by indicating organ-specific and age- but not aging-dependent changes in the localization of spontaneously generated nuclear 8-OHdG in intact rats. The immunohistochemical approach has advantages for assessing variation of 8-OHdG formation at the cellular level not accessible to the HPLC-ECD method.

8-Hydroxy-2'-Deoxyguanosine↗