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Biomedical subjects

T Hotta

Publications and source records attributed to T Hotta.

At least 145 records · Page 8Linked to original sources
PubMed1996

Clinical evaluation of chemosensitivity testing for patients with colorectal cancer using MTT assay.

PURPOSE: Colorectal cancer is one of the tumors most refractory to treatment by chemotherapy. The chemosensitivity test should be performed to individualize the chemotherapy for patients with colorectal cancer, which is less sensitive for anticancer drugs. The present study was designed to determine the chemosensitivity in fresh human colorectal cancer, using highly purified tumor cells, and the correlation of this sensitivity with clinical response. METHODS: We determined the chemosensitivity for cisplatin, mitomycin C, adriamycin, and 5-fluorouracil in vitro in 93 fresh human colorectal cancers using the MTT assay and performed chemotherapy according to results of the MTT assay. RESULTS: Inhibition rate of tumor cells for cisplatin was higher than those for other drugs. Fifteen patients who have evaluable lesions received chemotherapy according to results of the MTT assay. Clinical responses were obtained in 5 of 15 patients, and the inhibition rate for cisplatin was higher in responders than in nonresponders. CONCLUSIONS: It is suggested that the chemotherapy according to results of the MTT assay is effective in patients with colorectal cancer.

Adult↗
PubMed1996

Clonal and functional analysis for the augmentation of tumour-infiltrating lymphocytes by interleukin 4.

In the adoptive immunotherapy for cancer, the amounts of induced effector cells play a major role in improving therapeutic efficacy. We have already demonstrated that interleukin 4 (IL-4) augments proliferation of tumour-infiltrating lymphocytes (TILs) without altering the cytotoxic activity against autologous tumour cells. The present study is designed to investigate how IL-4 augments TILs by using established TIL clones in terms of IL-2/IL-2 receptor system. CD4+, CD8+ and CD4+ CD8+ (double positive) TIL clones were established from cancer patients. At clonal level, IL-4 augmented the proliferation of IL-2-activated TIL clones irrespective of phenotypes. In order to clarify the mechanism of IL-4 at clonal level, the blocking assay by anti-IL-2 receptor alpha and beta chain and binding assay of IL-2 on the cell surface and the measurement of the internalisation of IL-2 in the cell were performed. It was clarified that IL-4 up-regulated the IL-2 receptor and then augmented the action of IL-2 molecule on the cell surface stimulated by IL-4. Furthermore, binding IL-2 internalised rapidly into the cells. Thus, it is suggested that signal transduction is augmented and proliferation of TILs is enhanced by IL-4 via the action of IL-2/IL-2 receptor system.

DNA↗
PubMed1996

Fibronectin promotes the proliferation of cytotoxic T lymphocytes generated from cancer patients.

We studied whether fibronectin (FN) enhances the activity of autologous tumour-reactive cytotoxic T lymphocytes (CTLs) generated from cancer patients. The proliferation of CTLs stimulated by immobilised anti-CD3 monoclonal antibody and interleukin 2 (IL-2) was enhanced three or four times by immobilised FN. whereas soluble FN did not alter the DNA synthesis of CTLs. Moreover, the cytotoxic activity of CTLs was augmented by FN stimulation against autologous tumour cells [4 h 51Cr release assay: FN(+) 16.7 +/- 4.7% vs FN (-) 11.8 +/- 3.1%; 16 h 51Cr release assay: FN(+) 24.8 +/- 4.7% vs FN (-) 16.5 +/- 5.7%, P<0.05]. The major cell surface phenotype of CTLs with FN was CD3+, CD4+ and CD25+ in 6 weeks' culture. Cytotoxicity against autologous tumour cells was inhibited by anti-HLA class I monoclonal antibody (MAb). The autologous tumour-killing activity of CTLs was suppressed by the elimination of CD4+ cells. Moreover, the cytokine production of CTLs was augmented by FN stimulation. Especially, the production of IL-2, interferon gamma (IFN-gamma), and granulocyte macrophage colony-stimulating factor (GM-CSF) was significantly augmented by FN stimulation (P<0.05). Thus, CTLs generated by FN might have both killer and helper functions, since they could lyse autologous tumour cells and secrete various cytokines, including IL-2.

Adult↗
PubMed1996

Elevated serum interleukin-6 (IL-6) is derived from neoplastic lymphoid cells in patients with B-cell non-Hodgkin's lymphoma: correlation with extent of IL-6 expression and serum concentration.

We investigated the expression of interleukin-6 (IL-6) mRNA in tumours from 21 patients with B-cell non-Hodgkin's lymphoma (NHL). Total RNA, extracted from diagnostic tissue specimens, was subjected to semi-quantitative analysis for IL-6 mRNA by the reverse transcription-polymerase chain reaction (RT-PCR). The amount of IL-6 mRNA ws semi-quantified against that in pokeweed mitogen (PWM) stimulated peripheral blood mononuclear cells. The expression of IL-6 in neoplastic B cells was confirmed by immunohistochemistry. We then looked for correlations between the amount of IL-6 concentrations. The amount of IL-6 mRNA correlated with the circulating IL-6 concentration, suggesting that the malignant cells were the source of IL-6 in these patients with B-cell NHL. Our results suggest that the circulating IL-6 in patients with B-cell NHL is derived from the neoplastic lymphoid cells, and that neoplastic cells may act as modulators of the general status of patients with B-cell NHL.

Adolescent↗
PubMed1996

The CDKN2 gene alterations in various types of adult T-cell leukaemia.

The CDKN2 gene, encoding the cyclin-dependent kinase-4 inhibitor p16, is a putative tumour-suppressor gene because it is frequently altered in many malignant tumours. We analysed the CDKN2 gene in 44 cases of adult T-cell leukaemia (ATL) by Southern blot analysis, polymerase chain reaction-mediated single-strand conformation polymorphism (PCR-SSCP) analysis, and direct sequencing. Southern blot analysis detected a homozygous deletion of the CDKN2 gene in 5/44 patients (11.4%). Mutational analysis by the PCR-SSCP method and direct sequencing showed one nonsense mutation at codon 72 (nucleotide 232), and two missense mutations at codon 43 (nucleotide 146) and codon 97 (nucleotide 309, 3/44, 6.8%). Therefore we found changes in the CDKN2 gene, including point mutations, in 18.2% of the patients with ATL. Interestingly, most of these patients had acute type ATL. Our results suggest that the CDKN2 gene is inactivated not only by homozygous deletion but also by point mutation, and these alterations contribute to the aggressiveness of ATL.

Adult↗
PubMed1996

Combination phase I/II study of irinotecan hydrochloride (CPT-11) and carboplatin in relapsed or refractory non-Hodgkin's lymphoma. CPT-11/Lymphoma Study Group.

Irinotecan hydrochloride (CPT-11) is a new derivative of camptothecin which inhibits topoisomerase I. Phase II studies have demonstrated that CPT-11 is active against a broad spectrum of neoplasms including intractable non-Hodgkin's lymphoma. An early phase II study in lymphoma suggested that a schedule of daily infusions of 40 mg/m2/day for three or five consecutive days is more effective than a single infusion of 200 mg/m2 every three to four weeks. Carboplatin is also an active agent against lymphoma, and preclinical studies have shown that CPT-11 and its active metabolite have a synergistic effect with platinum compounds. To evaluate the maximal tolerated dose (MTD) and the therapeutic efficacy of CPT-11 in combination with carboplatin in relapsed or refractory non-Hodgkin's lymphoma, we conducted a combination phase I/II study. The starting dose of CPT-11 was 20 mg/m2/day (days 1 through 3 and 8 through 10), and dose escalations of 5 mg/m2/day increments were planned, with a fixed dose of carboplatin (300 mg/m2, day 1). Six of the eight patients receiving both agents at the starting dose level developed critical toxicities such as grade 4 hematologic (neutropenia 6/8, thrombocytopenia 1/8) and grade 3 non-hematologic toxicities (diarrhea 2/8, transaminase elevation 1/8). Further dose escalation of CPT-11 was halted, and the starting doses were judged to be the MTDs. The response rate (25%, 2/8) to the combination of the MTDs was not superior to that of CPT-11 alone in a previous phase II study (38%, 26/69), and the MTD of CPT-11 in combination with carboplatin was less than half the single-agent dose. We conclude that carboplatin is not recommendable for combination with CPT-11 in lymphoma patients. Other suitable agents for such a combination should be sought.

Abdominal Pain↗
PubMed1996

Expression of bone morphogenetic proteins in human osteogenic and epithelial tumor cells.

In addition to osteosarcomas some epithelial tumors also show bone induction, which is supposedly due to bone morphogenetic proteins (BMPs). However, the types of BMPs expressed in different kinds of tumors have not been studied extensively. In this study five human osteosarcoma and six human carcinoma cell lines were examined to investigate the bone induction and BMP mRNA expression. The cultured cells were transplanted in the subcutaneous tissue of athymic nude mice with or without diffusion chambers. Reverse transcription-polymerase chain reaction (RT-PCR) was used for the detection of BMP mRNAs. All osteosarcoma cell lines expressing all BMPs (BMP-1 to 7) examined, successfully formed bone or osteoid tissue irrespective of the use of a diffusion chamber. Bone formation was induced by diffusion chamber in an osteosarcoma cell line OST and a gastric adenocarcinoma cell line MKN45. OST cells lacked BMP-3 and 7, and MKN45 cells lacked BMP-3, 5 and 6. Our data suggest that BMP-3, 5, 6 and 7 are not always essential for bone induction in tumor cells.

Adenocarcinoma↗
PubMed1996

Overexpression of the MDM2 oncogene in leukemia and lymphoma.

A cellular phosphoprotein that binds to and inactivates p53 has recently been identified as a product of the oncogene MDM2. Amplification of the MDM2 gene was found in more than a third of sarcomas and in a subset of malignant gliomas. Despite the absence of amplification, the MDM2 gene was overexpressed in some types of leukemias and lymphomas. Overexpression was significantly more frequent in the low-grade type of B-cell non-Hodgkin's lymphoma (B-NHL) than in the intermediate/high grade types of lymphoma and the overexpression was also significantly more frequent in the advanced rather than the earlier stages of B-cell chronic lymphocytic leukemia (B-CLL) and B-NHL. This suggests that MDM2 could play a role, via the p53 pathway, in tumorigenicity and/or in disease progression in some hematological malignancies. However, in the light of our findings that, in a few cases, both the overexpression of MDM2 and mutant-type p53 was seen, it is possible that MDM2 overexpression may also promote neoplastic growth by mechanisms other than inactivation of the p53 protein.

Animals↗
PubMed1996

[A case of cranial hypertrophic pachymeningitis with intracranial hemorrhage].

A case of cranial hypertrophic pachymeningitis of unknown etiology in a patient with 15-year history of headaches, cranial nerve palsies, and gait disturbance is reported. A 77-year-old woman was brought to our institute in a coma. CT revealed intracerebral hemorrhage in the right temporal lobe and thickening of the falx and tentorium. Fifteen years previously the patient had undergone CT scanning because of headaches, cranial nerve palsies, and progressive gait disturbance and a thickened tentorium, mild hydrocephalus and edematous change in the right temporal lobe had been reported. Since the etiology of her symptoms was unclear at the time, she did not receive adequate treatment. Her symptoms gradually progressed thereafter, and her visual acuity and hearing deteriorated. MR imaging in 1994 showed the thickened tentorium as a hypointense area with hyperintense edges on Gd-DTPA enhanced images. Angiography revealed narrowing of posterior portion of the superior sagittal sinus. The patient's condition rapidly deteriorated due to the intracranial hypertension and she subsequently died. Autopsy revealed a thickened tentorium with xanthochromic surface. This hypertrophic change was also seen in the dura mater of the posterior and middle cranial fossa. Microscopic examination of the thickened tentorium revealed extensive fibrous tissue with a chronic inflammatory infiltrate, predominantly of lymphocytes. No specific lesions were revealed by staining with hematoxylin-eosin, PAS, Gram's or Ziehl-Neelsen stains. The patient had no inflammatory or infectious diseases of other organs, and a diagnosis of idiopathic cranial hypertrophic pachymeningitis of unknown etiology was made. Considering the above findings, the thickened tentorium depicted as a hypointense area on the T1- and T2-weighted images and the Gd-enhanced edges of the tentorium are thought to be represent fibrous tissue and inflammatory regions, respectively.

Aged↗
PubMed1996

Detection of minimal residual disease B cell lymphoma by a PCR-mediated RNase protection assay.

To detect and monitor tumor cells in the bone marrow (BM) or peripheral blood (PB) of patients with B cell lymphoma, we used the PCR-mediated RNase protection assay to identify the complementarity determining regions (CDR)-III gene rearrangement. This method required neither determination of nucleotide sequences nor construction of tumor-specific oligonucleotide probes or primers. The sensitivity of this assay using B cell lines as well as clinical samples revealed one tumor cell in a background of 10(4)-10(5) normal cells. Using this assay we examined 31 patients with B cell lymphoma in whom an IgH rearrangement of initial tumor tissues was confirmed by Southern blot analysis. Twenty of 31 (65%) patients were able to be analyzed using this assay. Tumor cells in the BM and PB evident on routine morphological examination or surface marker analysis were confirmed by this assay in all the evaluable samples. Moreover, we detected tumor cells in the BM or PB of five patients in whom no tumor cells were identified by conventional methods. The PCR-mediated RNase protection assay is useful to detect minimal residual disease (MRD) in B cell lymphoma because it is highly sensitive, rapid and simple.

Adolescent↗
PubMed1996

[Adult-onset aqueductal stenosis caused by membranous occlusion in the aqueduct: a case report].

The authors report a case of adult-onset aqueductal stenosis caused by membranous occlusion of the aqueduct. The patient was a 35-year-old man, who suffered from progressive headache. On admission, computed tomography (CT) scan showed marked dilatations of the lateral and third ventricles. Midsagittal T1-weighted magnetic resonance imaging (MRI) scan showed a membranous occlusion at the lower end of the aqueduct, with dilatation of the proximal aqueduct and elevation of the tectum. Midsagittal cine-MRI demonstrated the cerebrospinal fluid flow in the aqueduct. The patient was diagnosed as having hydrocephalus resulting from membranous stenosis of the aqueduct by MRI. A ventriculo-peritoneal shunt operation was performed and his symptoms improved markedly. The membranous occlusion of the aqueduct is a rare cause of hydrocephalus. The etiology and therapy of aqueductal stenosis are discussed.

Adult↗
PubMed1996

[Overexpression of bcl-2 suppresses apoptotic cell death of the human leukemic cell line TF-1].

We analyzed the effect of overexpression of bcl-2 gene on cell cycle progression, using the growth factor dependent cell line, TF-1, derived from an erythroleukemia patient. TF-1 (bcl-2) cells, which were transfected with bcl-2 cDNA by the retrovirus vector system, survived and arrested in the G0-1 phase on GM-CSF removal. Centrifugal elutriation studies showed that G0-1-arrested subfraction of TF-1 (bcl-2) reentered the cell cycle with time delay upon GM-CSF re-addition, when compared with TF-1 (mock). A similar delay in cell cycle progression was observed during the recovery phase after 24h-exposure to staurosporine, a protein kinase C(PKC) inhibitor. These results imply functional involvement of bcl-2, both in the GM-CSF and the PKC signal transduction pathway and in G0-1 progression.

Apoptosis↗
PubMed1995

Mutational analysis of the CDKN2 (MTS1/p16ink4A) gene in primary B-cell lymphomas.

The CDKN2 gene located on chromosome 9p21 encodes the cyclin-dependent kinase-4 inhibitor p16. This gene is a putative tumor-suppressor gene because of its frequent alterations in many kinds of tumor cell lines. We analyzed the CDKN2 gene to evaluate its alterations in 52 primary specimens of non-Hodgkin's lymphoma (NHL) or chronic lymphocytic leukemia (CLL) of B-cell origin by Southern blot analysis, polymerase chain reaction-mediated single-strand conformation polymorphism (PCR-SSCP) analysis, and direct sequencing. By Southern blot analysis, we showed homozygous deletion of the CDKN2 gene in 3 of 42 patients with B-NHL (7.1%). After screening by PCR-SSCP analysis, direct sequencing identified one missense mutation at codon 72 (nucleotide 233) and two frameshifts due to a 35-bp deletion arising at codon 49 (nucleotides 163 to 175) in patients with B-NHL (3 of 42, 7.1%). In the patient carrying the missense mutation, hemizygous deletion of the CDKN2 gene was also suspected. In this study, we detected alterations in CDKN2 in 6 of 42 patients (14.3%) with B-NHL and in none of 10 patients with B-CLL. Our results suggest that the CDKN2 alterations contribute in tumorigenesis in some patients with B-NHL.

Adolescent↗
PubMed1995

Protective effect of granulocyte colony-stimulating factor against T-cell-meditated lethal shock triggered by superantigens.

The bacterial superantigens (SAg), toxic shock syndrome toxin-1 (TSST-1) and staphylococcal enterotoxin B (SEB), are powerful T-cell stimulators, triggering systemic release of lymphokines causing lethal shock in D-galactosamine (D-Gal)-sensitized mice. We show that pretreatment with recombinant human granulocyte colony-stimulating factor (rhG-CSF) protects mice against T-cell-mediated SAg-shock. In mice challenged with D-Gal/TSST-1, lethal shock was caused within 30 hours. In contrast, animals pretreated with two consecutive subcutaneous injections of 2 micrograms rhG-CSF with a 12-hour time interval showed only marginal signs of illness and no lethality after challenge with D-Gal/TSST-1. Mice treated with 5 micrograms rhG-CSF either 12 or 6 hours in advance also survived otherwise lethal doses of D-Gal/TSST-1. The protective effects of rhG-CSF pretreatment was also evident against lethal doses of D-Gal/SEB challenge and this protection was accompanied by suppression of systemic interleukin-2. However, rhG-CSF affected neither the proliferative responses of SAg-reactive T cells in vivo or in vitro nor their interleukin-2 production in vitro, implying that rhG-CSF may indirectly interfere with cytokine synthesis in T cells but not with T-cell-SAg binding itself. These results represent another beneficial effect of rhG-CSF as an anti-inflammatory agent against T-cell-mediated toxicity triggered by SAg.

Animals↗
PubMed1995

Clinical significance of quantitative analysis of carcinoembryonic antigen assessed by flow cytometry in fresh human gastric cancer cells.

The expression of carcinoembryonic antigen(CEA) on tumor cells freshly excised from 51 patients with gastric cancer was studied using flow cytometry. The expression of CEA by flow cytometry was more quantitative than that by immunohistochemical staining. There was no relationship between the fluorescence intensity assessed by flow cytometry and serum CEA levels, except for patients with a high titer of serum CEA. The patients with high grade CEA expression on tumor cells by flow cytometry had poor prognoses, compared to patients with low CEA expression in undifferentiated gastric cancer. Thus, it is suggested that the quantitative CEA expression on tumor cells by flow cytometry could be a useful prognostic marker in postoperative gastric cancer patients.

Adenocarcinoma↗
PubMed1995

Generation of CD4+ cytotoxic T lymphocytes stimulated by immobilized anti-CD3 monoclonal antibody and interleukin-2 in cancer patients.

The proliferation of autologous tumor-reactive cytotoxic T lymphocytes (CTL), induced by autologous mixed lymphocyte tumor-cell culture, was remarkably enhanced by activation with immobilized anti-CD3 monoclonal antibody (MAb) and interleukin-2 (IL-2), as compared with IL-2 alone. The activated CTL exhibited high cytotoxicity against autologous tumor cells. Cytotoxicity against autologous tumor cells was inhibited by anti-HLA-DR MAb. In negative selection with immunomagnetic beads, cytotoxicity against autologous tumor cells was inhibited by the elimination of CD4+ cells. The major cell-surface antigens of the activated CTL were CD3+, CD4+, CD25+, CD45RO+ and CD45RA-, suggesting helper T cells, and the activated CTL produced IL-2. It is concluded that the CTL activated by immobilized anti-CD3 MAb and IL-2 were CD4 cells that had both killer and helper functions. Our findings indicate that adoptive immunotherapy using these activated CTL would be effective in cancer patients.

Antibodies, Monoclonal↗