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T Mitsudomi

Publications and source records attributed to T Mitsudomi.

At least 91 records · Page 5Linked to original sources
PubMed1993

Maximum length of tracheal autografts in dogs.

When a primary anastomosis of the trachea is not feasible, grafting is required. We assessed the maximum length of tracheal autografts in 25 dogs. We used the autografts in this experimental study to avoid the immunologic complexity of allografts. Sections of cervical trachea ranging in length from 2.4 cm (6 rings) to 5.9 cm (14 rings) were excised and reimplanted as autografts. To increase the blood supply, we wrapped each graft in the greater omentum, which was brought up through the diaphragm. Grafts longer than 4.0 cm (8 to 10 rings) frequently showed stenosis, dissolution, or both in the middle part of the graft as a result of ischemia in that area, as demonstrated by laser blood flowmetry and injection study. We conclude that there is a limit to the length of a tracheal autograft, even if the blood supply has been increased by wrapping with omentum.

Animals↗
PubMed1993

The sensitivity of hyperthermo-chemo-radiotherapy for neoplastic cells in vitro on contact-sensitive plates.

On plastic dishes, the Chinese hamster cell line (V-79) easily formed colonies and enabled us to examine the effects of various treatments utilizing a colony formation assay while a different human cancer cell line (KSE-1) was found to have a low colony-forming ability which made it difficult to examine when using only a small number of cells. However, on the contact-sensitive plate (CSP), the KSE-1 line was able to form a sufficient amount of colonies in order to conduct examinations. Using CSPs, we were able to investigate the killing effects of various treatments on two malignant cells (V-79 and KSE-1). For the V-79 cells, hyperthermo-chemo-radiotherapy (HCR) was observed to be more effective than any other treatment. For KSE-1 cells, on the other hand, bleomycin had little killing effect, while both radiotherapy alone or hyperthermo-radiotherapy in doses of more than 4 Gy X-ray were found to be effective. These results indicated that it is necessary to examine the sensitivities of cells to different treatments in clinical cases in order to avoid non-effective treatments. In this report, we suggest that the use of CSPs allows for the effective examination of the effects of HCR while using only a small number of malignant cells, which have a low cloning efficiency on plastic surfaces.

3T3 Cells↗
PubMed1993

A novel germline p53 splicing mutation in a pediatric patient with a second malignant neoplasm.

A novel germline p53 splicing mutation was identified in a pediatric patient with two metachronous primary cancers that are constituent tumors of the Li-Fraumeni syndrome. Genomic DNA from the second tumor showed the same mutation and loss of heterozygosity at the p53 locus. The mutant mRNA and protein were present in the tumor tissue. In contrast, in the normal tissues bearing the germline mutation in the heterozygous state, predominantly normal mRNA was expressed and the mutant p53 protein was not detectable. The functional silence and relative lack of mutant p53 mRNA expression in the normal tissues of this patient may be caused by decreased stability or decreased production. If this proves a more general pattern of expression of mutant p53 in individuals with germline mutations, these findings may explain the paucity of tumors in individuals affected with the Li-Fraumeni syndrome.

Adult↗
PubMed1992

Frequency and diversity of p53 mutations in childhood rhabdomyosarcoma.

The p53 gene was examined in primary or metastatic tumors from six patients with rhabdomyosarcoma (RMS) and in five RMS cell lines by screening methods including single-strand conformation polymorphism analysis, the RNase protection assay, sequencing of complementary DNA subclones, and Southern blotting. Six original tumors were of embryonal histology, four alveolar, and one mixed. p53 mutations were identified in four of the six tumors or cell lines derived from tumors with embryonal histology and in one of the four with alveolar histology. Consistent with p53 allele loss, each mutation was found in the homo- or hemizygous state. One tumor showed a G to C transversion at p53 codon 213 (arginine to proline), and another showed deletion of the entire gene. The p53 mutations in cell lines included a codon 248 C to T transition (arginine to tryptophan) in RD and a codon 280 A to T transversion (arginine to serine) in RH30. The cell line CTR contained a 4-base pair deletion at codons 219/220 in exon 6 with resultant frame shift and premature termination in exon 7. These data support the role of diverse types of p53 mutations in the pathogenesis and/or progression of a significant proportion of cases of childhood RMS.

Adolescent↗
PubMed1992

Hereditary and acquired p53 gene mutations in childhood acute lymphoblastic leukemia.

The p53 gene was examined in primary lymphoblasts of 25 pediatric patients with acute lymphoblastic leukemia by the RNase protection assay and by single strand conformation polymorphism analysis in 23 of 25 cases. p53 mutations were found to occur, but at a low frequency (4 of 25). While all four mutations were identified by single strand conformation polymorphism, the comparative sensitivity of RNase protection was 50% (2 of 4). Heterozygosity was retained at mutated codons in 3 of 4 cases. One pedigree was consistent with the Li-Fraumeni syndrome, and bone marrow from both diagnosis and remission indicated a germline G to T transversion at codon 272 (valine to leucine). Although members of another family were affected with leukemia, a 2-bp deletion in exon 6 was nonhereditary. The other two nonhereditary p53 mutations included a T to G transversion at codon 270 (phenylalanine to cysteine) and a G to C transversion at codon 248 (arginine to proline). These data support the role of both hereditary and acquired p53 mutations in the pathogenesis and/or progression of some cases of childhood acute lymphoblastic leukemia.

Adolescent↗
PubMed1992

Absence of hereditary p53 mutations in 10 familial leukemia pedigrees.

Germline p53 mutations have been identified in the Li-Fraumeni syndrome but the role of such mutations in familial leukemia is not established. The p53 gene was examined by single-strand conformation polymorphism analysis of exons 4-8 in 10 families with multiple members affected with leukemia. The diagnoses included acute and chronic leukemias and Hodgkin's disease. Identified in two families were p53 mutations that were nonhereditary. These included a 2-bp deletion in exon 6 found in the lymphoblast DNA of one child whose sibling, cousin, and several adult relatives had acute leukemia. The other nonhereditary p53 mutation was a transition at codon 248 (CGG to CAG, arginine to glutamine) found in the lymphoblasts of a patient with a preleukemic syndrome and acute lymphoblastic leukemia (ALL) whose brother is a long-term survivor of ALL. Thus, p53 mutations were found to occur in two families but both were nonhereditary. Moreover, in the remaining eight families no p53 mutation was identified in the regions of p53 where most mutations have been found in other cancers. Although p53 mutations sometimes may be present, they do not appear to be a primary event responsible for hereditary susceptibility to familial leukemia. This study suggests involvement of other genes or mechanisms.

DNA, Neoplasm↗
PubMed1992

p53 gene mutations in non-small-cell lung cancer cell lines and their correlation with the presence of ras mutations and clinical features.

We screened 77 non-small-cell lung cancer (NSCLC) cell lines for mutations of the p53 gene using a single-strand conformation polymorphism (SSCP) assay. We found that 57 cell lines (74%) had mutations of the p53 gene. Three cell lines had a deletion of the p53 gene. Of the remaining 54 cell lines, 49 cell lines were sequenced and 52 mutations were confirmed. In contrast to previously published p53 mutations in other human tumors, the p53 gene mutations in NSCLC were diverse with regard to the location and nature of the mutations. The region corresponding to codons 144-166, which is outside the evolutionarily conserved regions, was a frequent site of p53 gene mutations in NSCLC. The presence of a p53 gene mutation was not associated with age, sex, histological types, culture site, treatment intent, presence of prior cytotoxic treatment, neuroendocrine differentiation, median culture time or patient survival. The prevalence of p53 mutations in cell lines with ras mutations did not differ from that in cell lines without ras mutations. However, p53 gene mutations in NSCLC cell lines with ras mutations tended to cluster in exon 8, suggesting the presence of a functional domain of the p53 gene relating to interaction with the ras gene. We conclude that p53 and ras mutations are frequent and apparently independent genetic alterations which play different roles in the pathogenesis, progression and prognosis of NSCLC.

Amino Acid Sequence↗
PubMed1992

High frequency of somatically acquired p53 mutations in small-cell lung cancer cell lines and tumors.

We analysed the p53 open reading frame (ORF) in 16 small-cell lung cancer (SCLC) cell lines by direct sequencing of cDNA/PCR products and in 20 SCLC tumors by chemical cleavage and single-strand conformation polymorphism analyses of genomic DNA/PCR products. Abnormalities of p53 were found in 16/16 cell lines (100%) and in 16/20 tumors (80%). In the SCLC cell lines, mutations (59% missense, 18% nonsense and 23% splicing) changing the coding sequence were dispersed between amino acids 68 and 342. In the tumor samples, while the mutations occurred predominantly in exons 5-8, other mutations were located outside these regions. G to T transversions were common, occurring in 32% of the cases. We found no p53 mutations in the corresponding normal tissue from 19 patients whose tumors had p53 lesions, indicating that the mutations were all somatically acquired. In analysing the clinical data of the patients we found no correlation between tumor response to therapy or survival and the location or type of mutations. We conclude from these data that: (1) p53 mutations are found in SCLC with high frequency; (2) p53 mutations in a significant fraction of cases generate cDNAs with nonsense or splicing mutations; and (3) to date, these mutations have all been somatically acquired events.

Base Sequence↗
PubMed1992

[Mutations of ras and p53 genes in human non-small cell lung cancer cell lines and their clinical significance].

We examined 77 non-small cell lung cancer (NSCLC) cell lines for mutations of 3 ras genes and p53 gene, and ras mutations were detected by designed RFLP assay generated by mismatched primers during the PCR step and p53 gene mutations were detected using SSCP analysis. The incidence of ras mutations were 27/77 (35%) while that of p53 gene mutations were 57/77 (74%). The incidence of ras mutations in cell lines with p53 mutations were not different from that without p53 mutations, suggesting that they occurred independently. Neither ras nor p53 mutations correlated with histologic subtype, disease extent, in vitro culture time nor prior therapy status. The patients whose cell lines had any ras mutations survived for shorter period of time not only among the patients who were treated with curative intent but among those treated with palliative treatment. The Cox proportional hazards model predicted the higher risk for patients with ras mutations but not those with p53 mutations. We conclude that ras and p53 mutations are frequent, apparently independent genetic alterations which play different roles in NSCLC and that this information should be utilized in surgical oncology in the near future.

Carcinoma, Non-Small-Cell Lung↗
PubMed1992

Expression of mutant p53 proteins in lung cancer correlates with the class of p53 gene mutation.

We investigated the immunocytochemical staining and immunoblotting characteristics of 33 different p53 mutant proteins identified in lung cancer cell lines (18 small-cell lung cancer and 15 non-small-cell lung cancer) using monoclonal antibodies pAbs 240, 421 and 1801. The p53 mutants studied were representative of those found in lung cancer and included three deletions, four nonsense, seven splicing and 19 missense lesions. Control cell lines included six B-lymphoblastoid cell lines and two lung cancer cell lines without p53 mutations. Immunocytochemistry demonstrated 16 cell lines (48%) with definite overexpression of p53 protein (the high-expresser group of mutants), while in the remainder of cases either no p53 expression or low levels of p53 protein expression were found (the low-expresser group of mutants). The type of p53 mutation correlated with the expresser group. High expressers all had p53 missense mutations in exons 5-8, and immunocytochemistry identified 16/17 (94%) of these mutants. Several classes of p53 mutations occur in the low-expresser groups: deletions, splicing mutants, nonsense mutants and missense mutations outside of exons 5-8 all resulted in very low or undetectable levels of p53 protein. We conclude that there are low- and high-expression groups of p53 mutants in lung cancer and that the detection of protein expression in tumor cells by immunocytochemistry and immunoblotting is dependent upon the type of mutation of the p53 tumor-suppressor gene.

Blotting, Western↗
PubMed1991

Invasive human fibrosarcoma DNA mediated induction of a 92 kDa gelatinase/type IV collagenase leads to an invasive phenotype.

Proteolytic enzymes, such as gelatinase/type IV collagenase, play a pivotal role in cancer invasion and metastasis. Invasive human fibrosarcoma cells (HT1080) secrete two species of gelatinase/type IV collagenase, 68-72 kDa and 92 kDa enzymes. The purpose of this study is to elucidate which species of gelatinase/type IV collagenase plays a more important role in invasion. We have found that HT1080 x human fibroblast hybrids have reduced ability to invade a reconstituted basement membrane (Matrigel) in vitro compared to HT1080 cells, and abundantly secrete only the 68-72 kDa gelatinase/type IV collagenase. These data suggest that the 92 kDa gelatinase/type IV collagenase may be more important in HT1080 cell invasion. We next transfected HT1080 genomic DNA into non-invasive mouse C3H/10T1/2 fibroblast cells, which secrete only 68-72 kDa gelatinase/type IV collagenase. Four invasive transfectants were established. These invasive transfectants secreted the 92 kDa gelatinase/type IV collagenase in addition to the 68-72 kDa gelatinase/type IV collagenase, whereas non-invasive control DNA transfectants did not secrete the 92 kDa gelatinase/type IV collagenase. These results suggest that the induction of the 92 kDa gelatinase/type IV collagenase is important in the invasive phenotype.

Animals↗
PubMed1991

Mutations in the p53 gene in primary human breast cancers.

Twenty-six primary breast tumors were examined for mutations in the p53 tumor suppressor gene by an RNase protection assay and nucleotide sequence analysis of PCR-amplified p53 complementary DNAs. Each method detected p53 mutations in the same three tumors (12%). One tumor contained two mutations in the same allele. Single strand conformation polymorphism analysis of genomic DNA and complementary DNA proved more sensitive in the detection of mutations. Combining this technique with the other two a total of 12 mutations in the p53 gene were demonstrated in 11 tumors (46%), and a polymorphism at codon 213 was detected in another tumor. Loss of heterozygosity on chromosome 17p was detected by Southern blot analysis in 30% of the tumor DNAs. Not all of the tumors containing a point mutation in p53 also had loss of heterozygosity of the remaining allele, suggesting that loss of heterozygosity may represent a later event.

Base Sequence↗
PubMed1991

ras gene mutations in non-small cell lung cancers are associated with shortened survival irrespective of treatment intent.

We analyzed 66 non-small cell lung cancer cell lines for mutations at codons 12, 13, and 61 of all three ras genes and correlated the findings with patient survival. We used designed restriction fragment-length polymorphisms to detect mutations after amplification of ras-specific sequences by the polymerase chain reaction. We found 19 mutations of ras genes (29%), and 11 of these 19 (58%) were at codon 12 of the K-ras gene. By univariate analysis, the presence of any ras mutation in cell lines from patients who received curative intent treatment was associated with a shorter survival (P2 = 0.002). For patients who received only palliative treatment, detection of K-ras mutations at codon 12 was associated with a shortened survival (P2 = 0.0103), but this analysis was not statistically significant for the group with any ras mutation (P2 = 0.093). The Cox proportional hazards model also predicted a higher risk for patients with any type of ras mutations. We conclude that ras mutations, present in a subset of non-small cell lung cancers, are independently associated with the shortened survival of patients, irrespective of treatment intent.

Analysis of Variance↗
PubMed1991

DNA polymerase-alpha as a putative early relapse marker in non-small cell lung cancer. An immunohistochemical study.

The authors examined 72 fresh frozen sections of primary lung cancer using a monoclonal antibody for DNA polymerase-alpha (POL-alpha). The percentage of POL-alpha-positive cells was 17.3%. The tumors were divided into two groups. In one group, more than 5% of the POL-alpha-positive cells were designed POL-alpha-positive, and in the other group less than 5% were POL-alpha-negative. The incidence of POL-alpha-positive in men was statistically higher than that in women (P less than 0.05). The incidence correlated with the T (tumor) status, with a significance. Based on data on 43 patients with non-small cell lung cancer and who underwent a complete resection, the 3-year disease-free survival rates of POL-alpha-positive and POL-alpha-negative cells were 42% and 81%, respectively (P less than 0.05). When the patients were restricted to the class of N0 disease or Stage I, all the patients diagnosed as a cases of a relapse of lung cancer were POL-alpha positive. The 3-year disease-free survival rate of patients with POL-alpha negative was 100%. Our data suggest that in cases of non-small cell lung cancer, POL-alpha expression is associated with the extent of malignancy and a recurrence. Thus POL-alpha may prove to be a pertinent marker of an early relapse.

Adult↗
PubMed1991

Prognostic value of c-erbB-2 protein expression in human lung adenocarcinoma and squamous cell carcinoma.

203 primary human lung tumours, of which 119 were adenocarcinoma and 84 were squamous cell carcinoma, were investigated immunohistochemically for the expression of c-erbB-2 protein. Positive staining was evident in 33 (28%) of adenocarcinomas and 2 (2%) of squamous cell carcinomas. In cases of adenocarcinoma, c-erbB-2 was present in 18% of those with stage I disease. In stage IIIA, stage IIIB and stage IV cases, c-erbB-2 was present in 39%, 50% and 60%, respectively (I vs. IIIA and I vs. IIIB: P less than 0.05, I vs. IV: P less than 0.01). The 5-year survival rates of c-erbB-2 positive patients and those who were negative were 30% and 52%, respectively, with a statistically significant difference (P less than 0.01). These observations suggest that when the expression of c-erbB-2 correlates with invasiveness of the tumour, this correlation may serve as a prognostic indicator, particularly in cases of adenocarcinoma of the lung.

Adenocarcinoma↗
PubMed1991

Prognostic implication of transforming growth factor alpha in adenocarcinoma of the lung--an immunohistochemical study.

We examined for transforming growth factor alpha (TGF alpha) in adenocarcinomatous lesions of the lung tissues excised from 138 patients, with use of the avidin-biotin-peroxidase complex (ABC) method. TGF alpha was present in the cytoplasm of the adenocarcinoma. Our objective was to determine if TGF alpha could serve as a prognostic parameter. We divided 138 patients into two groups according to the concentration of TGF alpha. Ninety-two patients had a high concentration of TGF alpha, in over 75% of the tumour cells, while 46 had a low concentration, that is in less than 75% of the cells. The 5-year survival rates of patients with high TGF alpha and low TGF alpha were 39% and 64%, respectively (P less than 0.05). Our data suggest that evidence of a high immunoreactivity of TGF alpha can serve as a prognostic parameter in adenocarcinoma of the lung.

Adenocarcinoma↗