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T Mitsudomi

Publications and source records attributed to T Mitsudomi.

At least 37 records · Page 2Linked to original sources
PubMed1998

Increased expression of cyclooxygenase 2 occurs frequently in human lung cancers, specifically in adenocarcinomas.

Cyclooxygenase (COX)-2 expression was immunohistochemically examined in 59 human lung cancers as well as in normal and premalignant lung specimens. In contrast to scattered weak reactivity seen in normal peripheral airway epithelial cells, markedly up-regulated COX-2 expression was detected in about one-third of atypical adenomatous hyperplasias and carcinoma in situ specimens, and a significant increase in COX-2 expression was observed in 70% of invasive adenocarcinoma cases. Interestingly, the proportion of adenocarcinoma cells with marked COX-2 expression was much greater in lymph node metastases than in the corresponding primary tumors. In contrast, small cell carcinomas showed virtually negligible expression, and squamous cell carcinomas showed infrequent and low expression. These findings suggest that an increase in COX-2 expression may be associated with the development of adenocarcinomas and possibly with acquisition of an invasive and metastatic phenotype.

Adenocarcinoma↗
PubMed1998

p27KIP1 in human lung cancers: differential changes in small cell and non-small cell carcinomas.

Small cell lung cancers (SCLCs) and non-small cell lung cancers (NSCLCs), two major categories of human lung cancers, have been shown to exhibit considerably different clinicopathological, biological, and molecular genetic characteristics. Inactivation of cyclin-dependent kinase inhibitors is now thought to play an important part in the pathogenesis of this fatal disease. In the present study, we show that in vitro p27KIP1 expression was associated with cell density-dependent growth inhibition in human lung epithelial cells in vitro, whereas in vivo, p27KIP1 expression in lung cells showed an inverse correlation with proliferative activity in the developing and adult normal lungs. Our immunohistochemical examination of 166 lung tumor specimens also revealed a striking difference in p27KIP1 expression between SCLCs and NSCLCs. Of 149 NSCLCs, 107 (72%) showed reduced p27KIP1 expression, with 8 being virtually negative. Furthermore, p27KIP1 expression status was found to be a significant prognostic factor for patient survival in the analysis of the 149 primary, resected NSCLC cases (P = 0.03 by the log-rank test). In contrast, all SCLC specimens thus far examined exhibited significantly increased staining when compared to the corresponding normal lung epithelium. These findings provide additional evidence for the heterogeneity prevalent in human lung cancers and suggest that p27KIP1 might play distinct biological roles in the pathogenesis of the two major histological categories, warranting additional studies to elucidate the functional consequences of such differences.

Adult↗
PubMed1998

Frequency of MAGE-3 gene expression in HLA-A2 positive patients with non-small cell lung cancer.

Melanoma tumor antigens, MAGE-1 and -3 are presented on HLA-A1 and -Cw*1601, or -A1 and -A2, respectively, to the corresponding cytotoxic T lymphocytes (CTL). If CTL recognizing these antigens were generated in patients, clones of positive tumor cells should be eliminated. To ascertain whether such an immunological response is active in patients with lung cancer and to determine what fraction of lung cancer patients are candidates for MAGE oriented immunotherapy, we assessed the relationship between HLA-A1 or -A2 expression and MAGE-1 or -3 gene expression in their tumors. MAGE-1 and -3 were detected in 18/55 (33%) and 23/55 (42%), respectively, by reverse transcriptase (RT)-polymerase chain reaction (PCR). Allele specific PCR revealed HLA-A1 and -A2 alleles to be expressed in 0/55 (0%) and 22/55 (40%) of our cohort, respectively. Among the 22 patients with HLA-A2 genotype, expression of HLA class I antigens detectable by immunohistochemistry was lost in five (23%) cases. The frequency of MAGE-3 expression in HLA-A2 patients was 5/17 (29%), somewhat lower than that of patients without HLA-A2 expression, 18/38 (47%), although the difference was not statistically significant (P = 0.17). Neither was there a significant association between HLA-A2/MAGE-3 co-expression and survival (P = 0.15, logrank test). We conclude that there is no clear evidence for elimination of lung cancers co-expressing HLA-A2 and MAGE-3 in vivo. Approximately 10% (5/55) of Japanese lung cancer patients are potential candidates for MAGE-3-based immunotherapy.

Adult↗
PubMed1998

p53 mutations in non-small-cell lung cancers occurring in individuals without a past history of active smoking.

Accumulating evidence suggests that the p53 gene is a good target for molecular epidemiological studies. We previously reported an association between the presence of p53 mutations and lifetime cigarette consumption. Although over 675 p53 mutations have been reported in lung cancers in the literature thus far, very little is known about the nature of such changes in lung cancers in the absence of a smoking background. In the present study, we therefore analysed 69 non-small-cell lung cancer specimens from individuals without any history of active smoking and identified p53 mutations in 26% of the cases. Statistical analysis of the present cohort of non-smokers also showed absence of significant relationship between p53 mutations and age, sex, histological type or disease stage. Comparison of mutational spectra between the present results in non-smokers and previously reported mutations in smokers clearly demonstrated G:C to T:A transversions to be significantly less frequent in non-smokers than in smokers (OR 5.35, 95% CI 1.77-16.12). Interestingly, G:C to C:G and G:C to A:T mutations were also observed in tumours of non-smokers at similar frequencies to G:C to T:A mutations, suggesting that these mutations can occur relatively frequently in the absence of active smoking. This study is, to our knowledge, the largest so far analysing a well-defined cohort of non-smokers in a single laboratory.

Adult↗
PubMed1998

p53 alteration, proliferating cell nuclear antigen, and nucleolar organizer regions in thymic epithelial tumors.

We examined p53 protein expression, p53 gene mutation, proliferating cell nuclear antigen (PCNA), and argyrophilic nuclear organizer regions (AgNOR), in 30 patients with surgically-treated thymic tumors (26 thymoma and 4 thymic carcinoma cases). p53 expression ratio with DO-1 was divided as p53 negative (0% positivity), low expressor (<10% positivity), high expressor (>10% positivity). The incidence of p53 low and high expressor in thymoma were 19% (5/26) and 8% (2/26), respectively. p53 immunopositivity in thymoma was significantly correlated with PCNA labeling index (LI). p53 expression ratio in invasive thymoma (33%) tended to be higher than that in non-invasive thymoma (18%). p53 expression was detected in one of the thymic carcinoma. There were no p53 gene mutations in 15 invasive thymoma, although one of four (25%) thymic carcinomas showed two point mutations. p53 gene alterations seem to be associated with malignant activity of tumor cells, and therefore detection of p53 gene mutations is useful as a diagnostic factor.

Adult↗
PubMed1997

Micrometastatic tumor cells in the bone marrow of patients with non-small cell lung cancer.

BACKGROUND: This study was designed to evaluate the incidence and clinical implications of detection of micrometastatic cancer cells in bone marrow aspirates of patients with operable non-small cell lung cancer. The relationship between micrometastatic cells and p53 overexpression in the primary tumor was also assessed. METHODS: Thirty-nine patients with stages I through III non-small cell lung cancer who underwent curative resection were entered into this study. Immunohistochemistry with monoclonal antibody to cytokeratin 18 was used to detect tumor cells in bone marrow. Immunostaining of p53 protein in the corresponding primary tumors was also done. RESULTS: Cytokeratin 18-positive cells were detected in 15 (39%) of the 39 patients. Overexpression of p53 was associated with positivity of the tumor cells in the bone marrow at borderline significance (14/29 versus 1/10; p = 0.0574). The patients with cytokeratin 18-positive cells in bone marrow demonstrated a significantly earlier recurrence than those without such cells (p = 0.0083, log-rank test). CONCLUSIONS: Micrometastatic cancer cells were frequently present in bone marrow of patients with operable non-small cell lung cancer and may be a significant predictor of early recurrence. Further evaluation of this method may be useful in identifying patients with non-small cell lung cancer who are most likely to benefit from adjuvant chemotherapy.

Aged↗
PubMed1997

Relationship between early recurrence and micrometastases in the lymph nodes of patients with stage I non-small-cell lung cancer.

OBJECTIVE: This retrospective study was designed to detect occult micrometastases in the lymph nodes with the use of monoclonal anti-cytokeratin reagent, which is specific for epithelial cells but not for lymphocytes or plasmacytes, as well as to assess the relationship between the presence of occult micrometastases in the lymph nodes and an early relapse in patients with stage I non-small-cell lung cancer. METHODS: The paraffin-embedded sections of 973 regional lymph nodes from 44 patients with stage I non-small-cell lung cancer were studied. We used CAM-5.2 as the primary monoclonal anti-cytokeratin reagent and an indirect staining technique with the streptavidin-biotin-peroxidase complex method. RESULTS: We identified cytokeratin-positive cells in 31 (70.5%) of 44 patients and in 91 (9.4%) of the 973 lymph nodes. Of these 31 patients with cytokeratin-positive cells, 19 and 12 were restaged as having N1 and N2 disease, respectively. Thirteen patients had recurrent disease at 17 sites during the follow-up. Two of these recurrences were in the mediastinal nodes and the other 15 occurred at distant organs. Twelve of the 13 patients had micrometastatic disease in the regional lymph nodes. Disease-free survival duration was significantly shorter in the patients with micrometastases in the mediastinal lymph nodes than in patients with node-negative disease (p = 0.004). The independence of this prognostic significance was demonstrated by a multivariate analysis. CONCLUSION: These findings indicate that the detection of occult micrometastases in the mediastinal lymph nodes with monoclonal antibodies to cytokeratin can thus be used to predict an early relapse in patients with stage I non-small-cell lung cancer.

Aged↗
PubMed1997

Mutations of the P53 tumor suppressor gene as clonal marker for multiple primary lung cancers.

OBJECTIVES: Second primary lung cancers are prevalent after treatment for initial lung cancer, and the lung is also one of the most frequent sites for recurrence after removal of early-stage lung cancer. The objective of the present study is to clarify the clonal origin of the second tumor with the p53 gene mutation used as a clonal marker. METHODS: Of 794 consecutive patients who underwent pulmonary resection for primary lung cancer from 1980 to 1993, 22 required second pulmonary resection during the follow-up period, with a median interval of 38 months. We examined 16 of these patients for mutations of the p53 gene occurring in exons 5 through 8 by the polymerase chain reaction/single strand conformation polymorphism method. Differential diagnosis was also made on a morphologic basis, considering the degree of cellular differentiation and cytologic subtypes. RESULTS: Nine of the 16 patients analyzed had at least one p53 mutation in their tumors. We were thus able to make molecular diagnoses for these patients. The mutational status of the p53 gene was discordant in all nine patients, suggesting a different clonal origin despite the fact that six of them had almost identical histologic features. CONCLUSIONS: Analysis of p53 gene mutations was thus useful in distinguishing second primary lung cancers from recurrent tumors. The observed heterogeneity of p53 status was also in line with the "field cancerization" concept.

Adenocarcinoma↗
PubMed1997

K-ras and p53 mutations are an independent unfavourable prognostic indicator in patients with non-small-cell lung cancer.

We examined 159 consecutive cases of non-small-cell lung cancer (NSCLC) for a mutation at codon 12 of the K-ras gene and for a mutation of the p53 gene occurring in exons 5-8. Eleven (6.9%) had mutations of the K-ras (ras+) and 57 (35.8%) had mutations of the p53 (p53+). There were 95 cases (59.7%) with ras- p53-, seven cases (4.4%) with ras+/p53-, 53 cases (33.3%) with ras-/p53+ and four cases (2.5%) with ras+/p53+. The ras+ group had a worse prognosis than the ras group in all cases and in 107 early-stage cases (stage I-II, P<0.05). The p53+ group had a worse prognosis in 107 early-stage cases (P<0.01), but there was no statistically significant difference when 52 advanced-stage cases (stage III-IV) or all patients were considered. Both ras and p53 mutations were unfavourable prognostic factors in 94 cases with adenocarcinoma, but there was no statistical significance in 57 cases with squamous cell carcinoma. According to Cox's model, the pathological stage, ras mutation and p53 mutation were found to be independent prognostic factors. Our results suggest that ras and p53 mutations were independent unfavourable prognostic markers especially in the early stage of NSCLC or in adenocarcinoma.

Adult↗
PubMed1997

Combined carboplatin and cisplatin therapy in patients with advanced non-small cell lung cancer.

Combining cisplatin and carboplatin may eliminate some of the toxic effects of each agent and permit the use of higher doses, because these agents have different pharmacodynamics and dose-limiting toxicities. We investigated the safety and efficacy of these agents in combination. The toxicity profile was evaluated in a Phase I trial in 18 patients with advanced non-small cell lung cancer (NSCLC). Carboplatin was administered in doses ranging from 200 to 400 mg/m2 on day 1 and cisplatin at a dose of 80 mg/m2 on day 3. Only one cycle of chemotherapy was administered. Thrombocytopenia was the dose-limiting toxic effect. The maximal tolerated dose of carboplatin was 350 mg/m2. We then investigated the efficacy of the optimal dose of this combined chemotherapy in a Phase II trial in 13 patients. We used a carboplatin dose of 300 mg/m2 for safety in the Phase II trial. Three of 13 patients developed grade 3-4 hematologic toxicity, which was improved without major complications. A partial response was observed in 5 of 13 patients (38.5%). Combination chemotherapy with carboplatin (day 1, 300 mg/m2) and cisplatin (day 3, 80 mg/m2) showed promising effects in patients with advanced NSCLC.

Aged↗
PubMed1997

Aggressive pulmonary metastasectomies for synovial sarcoma.

A 51-year-old woman underwent a bilateral wedge resection of lung metastases through a median sternotomy 10 months after an initial operation for synovial sarcoma of the left lower extremity. Since then, five right and two left posterolateral thoracotomies have been performed over a 6-year period. The patient is presently doing well 7 years after the initial operation of the left lower extremity without any evidence of recurrence.

Adult↗
PubMed1997

[Delayed traumatic hernia diagnosed with magnetic resonance imaging].

A 30-year-old man was admitted to the hospital 7 years after an automobile accident during which a lumbar vertebra was fractured. Immediately after the accident he had neither thoracic nor abdominal symptoms. An X-ray film obtained 4 years after the accident showed elevation of the left side of the diaphragm. That elevation progressed over the next 3 years, although the patient had no symptoms. On admission, a chest X-ray film showed blunting of the left costo-phrenic angle and mobility of the shadow, which simulated a pleural effusion. A chest CT scan and barium studies showed that portions of the small intestine, transverse colon and descending colon were in the left side of the thorax, but the diaphragm was not seen. The patient was given a diagnosis of delayed traumatic diaphragmatic hernia after T1-weighted sagittsal magentic resonance images revealed the whole diaphragm and the hernial orifice. Magnetic resonance imaging can be very useful in the evaluation of diaphragmatic hernia.

Adult↗
PubMed1997

[A carcinoma arising from benign pleomorphic adenoma of the trachea].

A 69-year-old female complained of husky voice and dyspnea. Bronchofiberscopic examination revealed a tumor at the left side of the trachea, which obstructed approximately 80% of the tracheal lumen. Benign pleomorphic adenoma was diagnosed by biopsy. The tumor was removed by circumferenctial resection of the trachea with partial sternotomy adding to the 3 th intercostal transverse resection. Historical finding of the resected specimen revealed a carcinoma arising from benign pleomorphic adenoma of the trachea and residue of malignancy at the margin of the trachea and esophagus. Additional radiotherapy was performed (60 Gy). The postoperative course was uneventful for 4 months and one year.

Adenocarcinoma↗
PubMed1997

[Genetic alteration of lung cancer as a prognostic marker and its therapeutic implications].

Many genetic lesions found in non-small cell lung cancer (NSCLC) have been reported to be associated with a poor prognostic outcome of this disease. Such alterations include mutations of ras genes, overexpression of myc or erbB2 genes and inactivation of RB genes. Among them, the prognostic implications of the p53 gene have been most extensively studied; over 20 reports have been published. However, the significance of the p53 gene abnormality also still remains unclear. Therefore, we re-evaluated our 562 patients with NSCLC retrospectively to see if the p53 gene abnormality really had an effect on patients' survival in this large cohort. There was no effect of p53 gene abnormality on all patients with NSCLC or on those with squamous cell carcinoma, but p53 abnormality was a significant, independent prognostic marker in adenocarcinoma subset. We should plan a clinical trial of postoperative adjuvant therapy for patient with pulmonary adenocarcinoma incorporating information on the p53 gene status to possibly translate these findings into clinical practice.

Adenocarcinoma↗
PubMed1997

Prognostic significance of cyclin D1 and retinoblastoma expression in combination with p53 abnormalities in primary, resected non-small cell lung cancers.

This study was conducted to evaluate the prognostic significance of cyclin D1 and retinoblastoma (Rb) expression in combination with abnormal p53 accumulation in primary, resected non-small cell lung cancers (NSCLCs). We evaluated immunohistochemically the expression of cyclin D1 and Rb in 208 NSCLC patients whose resections were consecutively performed between January 1984 and December 1988 and determined their prognostic significance by comparison with follow-up data. Expression of cyclin D1 and Rb was detected immunohistochemically in 39 and 80% of the 208 NSCLCs, respectively. The Kaplan-Meier survival curve demonstrated that absence of cyclin D1 expression was significantly associated with shortened survival (P = 0.01 by the log-rank test), particularly in adenocarcinomas (n = 100; P = 0.004). Expression status of the Rb protein was not significantly associated with clinical outcome in any of the cohorts. The predictive power of these prognosticators was also assessed in combination with findings for abnormal p53 accumulation by multivariate analysis using the Cox proportional hazards modeling. Patients with cyclin D1-negative tumors had a significantly greater risk of earlier death than those with cyclin D1-positive tumors (risk ratio, 1.61; P = 0.03), particularly in adenocarcinomas (risk ratio, 2.49; P = 0.002). Cases showing abnormal p53 accumulation tended to have a shortened survival only when the tumors were adenocarcinomas (risk ratio, 1.75; P = 0.06). Absence of cyclin D1 expression may be a useful prognosticator for shortened survival in primary, resected NSCLCs with particular significance for adenocarcinomas. In contrast, Rb expression status is not a useful prognostic factor for any type of NSCLC.

Adenocarcinoma↗
PubMed1996

Somatic in vivo alterations of the JV18-1 gene at 18q21 in human lung cancers.

The chromosome region 18q21 is frequently deleted in lung cancers. Recent identification of JV18-1 at this locus led us to examine whether or not it might also be altered in lung cancers, as is the case for the closely related DPC4 tumor suppressor gene. A missense somatic mutation and a 9-bp in-frame deletion were detected in the highly conserved region of JV18-1 among 57 lung cancer specimens taken directly from patients. The total alterations in JV18-1 and DPC4, however, are not sufficient to account for all 18q21 deletions in lung cancers. These findings suggest that although JV18-1 and DPC4 may play roles in a limited fraction of lung cancers, another tumor suppressor gene may also exist in this chromosome region.

Carcinoma, Non-Small-Cell Lung↗
PubMed1996

Somatic in vivo alterations of the DPC4 gene at 18q21 in human lung cancers.

The chromosome region 18q21 has been shown to be frequently deleted in lung cancers. Recent identification at this locus of DPC4, a gene whose inactivation has been suggested to play a role in pancreatic carcinogenesis, prompted as to examine whether it might also be altered in lung cancers. Two missense and 2-bp frameshift somatic mutations in DPC4 were detected among 42 lung cancer specimens taken directly from patients. DPC4 mutations, however, were not present in all lung cancers carrying l8q21 deletions. These findings suggest that DPC4 may play a role in a limited fraction of lung cancers and that another tumor suppressor gene may also exist in this chromosome region.

Base Sequence↗