Biomedical subjects

Masakazu Sugaya

Publications and source records attributed to Masakazu Sugaya.

At least 19 recordsLinked to original sources

PubMed2007

Identification of HLA-A24 restricted shared antigen recognized by autologous cytotoxic T lymphocytes from a patient with large cell carcinoma of the lung.

The aim of the present study was to elucidate the tumor-specific cellular immunological responses occurring in a patient with large cell carcinoma of the lung who had no evidence of recurrence following surgical resections of both a primary lung lesion and a metastatic adrenal lesion. We analyzed an autologous tumor-specific cytotoxic T lymphocytes (CTL clone F2b), which were HLA-A*2402 restricted from regional lymph node lymphocytes. The F2b possessed T cell receptor (TCR) using the Valpha5 and Vbeta7 gene segment. The existence of precursor CTL (pCTL) against autologous tumor cells (A904L) was analyzed using CTL clone-specific PCR. Lymphocytes with the same TCR as F2b were detected in the primary tumor tissue, regional lymph node and the peripheral blood collected from the patient 3 years after the operation. Using the F2b, we identified a cDNA clone encoding the tumor antigen using cDNA expression cloning method. The gene was found to encode splicing variant of the Tara gene. Finally, we identified the 9-mer Ag peptide, using constructions of mini-genes. The F2b recognized 3 out of 7 HLA-A24 positive allogeneic tumor cell lines and in 1 out of 7 HLA-A24 negative allogeneic tumor cell lines when transfected with HLA-A24. This peptide is therefore considered to be potentially useful for performing specific immunotherapy in a significant proportion of lung cancer patients bearing HLA-A24.

Alternative Splicing↗

PubMed2006

Resistance to gefitinib.

Subsets of patients with non-small cell lung cancer (NSCLC) who carry somatic mutations in the epidermal growth factor receptor (EGFR) have responded remarkably well to a tyrosine kinase inhibitor (TKI), gefitinib. Despite the dramatic response to this inhibitor, most patients nevertheless ultimately have a relapse. We herein report a case of advanced NSCLC in a patient carrying mutated EGFR (delE746-A750) who had a relapse after dramatic improvement by gefitinib treatment. The DNA sequence of the EGFR gene in a tumor biopsy specimen obtained from the relapse site revealed the presence of a second point mutation, resulting in a threonine-to-methionine amino acid substitution at position 790 of EGFR, which could not be detected in the tumor specimen taken before the treatment. Screening subjects with EGFR mutations therefore allows us to identify patients who can be successfully treated with gefitinib. Such observations should also help us in the search for more effective therapies against a specific subset of NSCLC.

Antineoplastic Agents↗

PubMed2006

Identification of a new cancer/germline gene, KK-LC-1, encoding an antigen recognized by autologous CTL induced on human lung adenocarcinoma.

The purpose of our present study is to identify a tumor-specific antigen capable of inducing a specific cellular immune response in lung cancer patients. We established a lung adenocarcinoma cell line, designated as F1121L, and induced tumor-specific CTL clone H1 from regional lymph node lymphocytes of patient F1121. CTL clone H1 lysed autologous tumor cells in an HLA-B*1507-restricted manner, but not autologous EBV-B, phytohemagglutinin-blast cells, and K562. The CTL clone also recognized allogeneic HLA-B*1501- or 1507-positive lung cancer cell lines in the HLA-restricted manner. Using the CTL clone, we identified an antigen-coding gene by cDNA expression cloning technique. The gene consisted of 556 bp, including an open reading frame consisted of 113 amino acids, designated as Kita-kyushu lung cancer antigen 1 (KK-LC-1). A 9-mer peptide (KK-LC-1(76-84); RQKRILVNL) was identified as an epitope peptide. The genomic DNA of this antigen was located in chromosome Xq22. A reverse transcription-PCR analysis revealed that the mRNA of this gene was only expressed in the testis among normal tissues. It was expressed in 9 of 18 (50%) allogeneic non-small-cell lung cancer cell lines and in 40 of 100 (40%) non-small-cell lung cancer tissues. We thus identified a new tumor antigen-coding gene categorized as a cancer/germline gene by an autologous lung cancer and CTL system. The new cancer/germline gene was located in Xq22, which is apparently different from the locations of previously reported cancer/germline genes.

Adenocarcinoma↗

PubMed2006

A point mutation in the NFYC gene generates an antigenic peptide recognized by autologous cytolytic T lymphocytes on a human squamous cell lung carcinoma.

We have identified an antigen recognized by cytolytic T lymphocytes (CTL) on the autologous tumor cells of a nonsmall cell lung cancer patient. The antigenic peptide, presented by HLA-B*5201 molecules, was encoded by a mutated sequence in the gene coding for the C subunit of transcription factor NF-Y. The mutation was present in the tumor sample from which the cell line was derived, and appeared to be unique to the tumor of this patient. In a lymph node draining the tumor, precursors of CTL recognizing the autologous tumor cells were detected at a frequency of about 1/30,000 of the CD8 cells, and 85% of them recognized the mutated NF-YC peptide, suggesting that the patient mounted a T cell response against this antigen. These results strengthened the notion that unique tumor-specific antigens are highly represented not only in melanoma but also in other types of tumors, like nonsmall cell lung cancer.

Antigens, Neoplasm↗

PubMed2005

Epidermal growth factor receptor mutations are associated with gefitinib sensitivity in non-small cell lung cancer in Japanese.

The protein-kinase family is the most frequently mutated gene family found in human cancer. Gefitinib, an ATP-competitive inhibitor of epidermal growth factor receptor (EGFR), also appears to be particularly effective in adenocarcinoma of the lung and in patients without smoking history. To determine whether lung tumors sensitive to gefitinib contained mutations within the tyrosine kinase (TK) domain of EGFR, we screened exons 18-23 of EGFR of tumors in 20 patients with non-small cell lung cancer (NSCLC) who had been treated with gefitinib. Nine (45%) tumors had TK domain mutations. All mutations were observed in adenocarcinoma. Seven (77.8%) of 9 cases with mutated types showed sensitivity to gefitinib, while no cases of 11 with wild type showed gefitinib sensitivity. Such mutations were more frequently observed in patients who had never smoked (5/8 or 62.5%) than in smokers (4/12 or 33.3%). The patients with mutations of EGFR to have a more favorable prognosis than those with wild type (p=0.033). These data show that adenocarcinomas from patients who had never smoked comprise a specific subset of patients with NSCLC sensitive to gefitinib treatment.

Adult↗

PubMed2005

Expression of aldehyde dehydrogenase 2 in the normal esophageal epithelium and alcohol consumption in patients with esophageal cancer.

Alcohol consumption is a risk factor for esophageal cancer. Acetaldehyde, a highly toxic intermediate produced from ethanol, is converted to acetic acid mainly by aldehyde dehydrogenase 2 (ALDH2) in the metabolic pathway of ethanol. Fifty percent of Japanese have inactive ALDH2 due to genetic polymorphism, which is considered to be a risk factor associated with esophageal cancer. In our previous study, we have demonstrated that ALDH2 is expressed in the esophagus with a considerable variation among individuals. In this study, we further investigated the expression of ALDH2 in esophagus and its relationship with risk factors of esophageal cancer. Tissue specimens resected from 51 patients with esophageal cancer were analyzed by immunohistochemistry using ALDH2-antibody. The immuno-staining of ALDH2 in the esophageal epithelium was compared with both the drinking habit and the occurrence of flushing that is closely associated with the ALDH2 deficiency. ALDH2 was not detectable in 8 (16%) among 51 specimens. All of the 8 patients were non- or light-drinkers but not heavy-drinkers. Among 18 patients showing the high level ALDH2 expression in the esophagus, 15 patients (83%) were heavy-drinkers. Although the relationship between the ALDH2 deficiency and drinking habit is not clear, the patients with ALDH2 deficiency tend to be non- or light drinkers while heavy-drinkers tend to have the active form of ALDH2. These results suggest that both inactive and active forms of ALDH2 are induced in the esophagus by heavy drinking and also support a hypothesis that ALDH2 deficiency might be a high-risk factor of esophageal cancer for the individuals having a heavy-drinking habit. To our knowledge, this is the first study demonstrating the induction of ALDH2 in the esophagus by ethanol consumption.

Alcohol Drinking↗

PubMed2005

Identification of the HLA-Cw*0702-restricted tumor-associated antigen recognized by a CTL clone from a lung cancer patient.

PURPOSE: A large number of tumor-associated antigens have been used in vaccination trials for mainly melanomas. Our purpose of this study is to identify a novel tumor antigen useful for immunotherapy of lung cancer patients. EXPERIMENTAL DESIGN: Analysis of an autologous tumor-specific CTL clone F2a that was established from regional lymph node lymphocytes of a patient with lung cancer (A904) by a mixed lymphocyte-tumor cell culture. RESULTS: F2a recognized and killed autologous tumor cells (A904L), whereas it did not respond to autologous EBV-transformed B cells, phytohemagglutinin-blastoid T cells, and K562 cells. cDNA clone 31.2 was isolated by using cDNA expression cloning method as a gene encoding antigen. This gene was identical to the reported gene whose function was unknown. The antigen encoded by the cDNA was recognized by the CTL in a HLA-Cw*0702-restricted manner. Furthermore, a 9-mer peptide at positions 659 to 685 in cDNA clone 31.2 was identified as a novel epitope peptide. The CTL recognized some allogeneic cancer cell lines with HLA-Cw*0702 as well as some HLA-Cw*0702-negative cell lines when transfected with HLA-Cw*0702, thus indicating that the identified antigen was a cross-reactive antigen. CONCLUSIONS: Although exact mechanism to process the encoded protein and present the antigen in the context of HLA class I remains to be elucidated, the CTL recognized some of tumor cells in the context of HLA-Cw*0702 but did not recognize a variety of normal cells and also autologous EBV-transformed B cells. These results indicated that the antigen identified in this study may therefore be a possible target of tumor-specific immunotherapy for lung cancer patients.

Antigen Presentation↗

PubMed2005

Haplotype loss of HLA class I antigen as an escape mechanism from immune attack in lung cancer.

One of tumor escape mechanisms from the host's immunosurveillance system (i.e., a haplotype loss of HLA class I antigens) has been detected in various tumor cells. We hypothesize that the majority of tumor cells with normal HLA class I expression were attacked and eradicated by CTLs, and only a minority with an abnormal expression of HLA class I antigens could escape the host's immunosurveillance system. Using HLA class I-transfected tumor variants as stimulators in A904L lung cancer cell line, which has a haplotype loss of HLA class I antigens, both the transfected HLA-A26 and HLA-B39-restricted CTL lines were induced from autologous lymphocytes. However, only one HLA-B39-restricted CTL clone (CTL G3b) was established, and it was then used to identify the antigen. SGT1B [suppressor of G2 allele of SKP1 (SGT1), suppressor of kinetochore protein (SKP1)] was identified as the antigen recognized by CTL G3b. Further experiments using 13 subclones from a primary culture of A904L were found to confirm our above-mentioned hypothesis. Tumor cells with a normal HLA class I expression may thus be killed by CTL at an early stage of carcinogenesis, and only tumor cells with a haplotype loss of HLA class I antigens can escape an immune attack and develop into clinical cancer.

Amino Acid Sequence↗

PubMed2005

Immunohistochemical evaluation of cytochrome P450 (CYP) and p53 in breast cancer.

In breast cancer, cytochrome P450 (CYP) metabolizes both endogenous substrates (i.e. estradiol) and exogenous substrates (i.e. anticancer drugs), which is associated not only with tumor development and progression but also with efficacy of cancer treatment. Therefore, we examined the expression of CYPs (CYP2A6, CYP1B1 and CYP3A) and p53 in specimens from 34 Japanese patients with breast cancer by immunohistochemistry. The expression of CYP3A was not detected in the 34 cases. CYP2A6 was detected only in one specimen (2.9%). Twenty-eight specimens (82.4%) showed positive signals for CYP1B1 expression. Eight of 34 (23.5%) were positive for p53 expression. Positive rate of CYP1B1 in stage I disease (100%) was statistically higher than that in stage II - IV disease (70.0%). Positive rate of p53 was 21.4% (6/28) in CYP1B1-positive cases and 33.3% (2/6) in CYP1B1-negative cases. There was no significant relationship between CYP1B1 expression and p53 expression. In conclusion, the expression of CYP3A in breast cancer may be less frequent in Japanese population although the expression of CYP3A has been reported in 20% of breast cancer in Caucasian, suggesting that the CYP3A expression in breast cancer may be dependent on ethnic groups. Since CYP3A is involved in the conversion of tamoxifen to its metabolites, the variation of the CYP3A expression in breast cancer tissues among ethnic groups might cause differences in the efficacy of tamoxifen.

Adult↗

PubMed2005

Primary pulmonary collision cancer consisting of large cell carcinoma and adenocarcinoma.

A case of pulmonary collision tumor is herein reported. An abnormal shadow was discovered in the right lung of a 53-year-old man. A right upper lobectomy with a mediastinal lymph node dissection was performed. Based on the findings of a postoperative pathologic examination, this tumor was considered to be a collision tumor of large cell carcinoma and adenocarcinoma, as the distribution of each tumor was clearly separated. This case is the first report of a primary pulmonary collision tumor consisting of large cell carcinoma and adenocarcinoma.

Adenocarcinoma↗

PubMed2005

Tracheobronchopathia osteochondroplastica occurring in a subsegmental bronchus and causing obstructive pneumonia.

A 59-year-old man was referred to the University of Occupational and Environmental Health hospital because a chest roentgenogram obtained at an annual medical examination showed an abnormal shadow. We treated the patient for tracheobronchopathia osteochondroplastica, which caused segmental obstructive pneumonia that proved to be difficult to accurately diagnose before surgery.

Humans↗

PubMed2005

Identification of tumor associated antigens recognized by IgG from tumor-infiltrating B cells of lung cancer: correlation between Ab titer of the patient's sera and the clinical course.

We previously demonstrated that TIB recognize tumor antigens and produce antibodies against them. In the present study, we identified three tumor antigens recognized by TIB in lung cancer and evaluated whether changes in the antibody titer against these antigens correlated with the patient's clinical course. A lung cancer cell line, G603L, was established from a primary lung tumor of a patient, G603. Seven months later, adrenal metastasis was detected and surgically resected. The latter tumor was mildly infiltrated with B cells and xenotransplanted into SCID mice to obtain human IgG. A cDNA library was constructed from G603L and SEREX was carried out using TIB-derived IgG. The sero-reactive clones were sequenced and one of these antigens was revealed to be MAGE-B2 whereas the others were novel antigens. In the immuno-monitoring of the patient's sera, high antibody titer against MAGE-B2 was observed before operation and the titer decreased after resection of the primary tumor. It was elevated again at the time of adrenal metastasis, but then decreased after resection. The change in antibody titer against the second antigen was similar to MAGE-B2, and the antibody titer against the third antigen was low before the primary operation but increased at the time of recurrence. Our results suggest that TIB recognized tumor antigens and the antibody titers against these antigens were changed along with the patient's clinical course. Therefore, these antibodies could be used as tumor markers for the patient.

Aged↗

PubMed2004

Tumor specific expression of survivin-2B in lung cancer as a novel target of immunotherapy.

BACKGROUND: Survivin-2B is reported to be specifically expressed in numerous malignant tissues. Furthermore, survivin-2B includes the epitope peptide (survivin-2B(80-88)) which is capable of binding to HLA-A24. In this study, we evaluated whether survivin-2B could be a novel vaccine target against lung cancer. METHOD: (1) The differences in the survivin-2B expression between 15 sets of lung cancer tissues and normal lung tissues were investigated using RT-PCR. (2) The expression of survivin-2B was further examined in 42 lung cancer tissues, and the relationship between the expression and clinicopathologic factors was analyzed. (3) To compare the frequency of precursor CTL between survivin-2B positive and negative lung cancer patients, surivivin-2B(80-88) peptide-specific CTL were induced from regional lymph node lymphocytes (LNL) of four HLA-A24 (+) lung cancer patients, in whom two showed a positive survivin-2B expression of lung cancer while another two were negative, after stimulation with surivivin-2B(80-88). RESULTS: Survivin-2B was specifically expressed in lung cancer tissues, and was expressed in 17 of 42 lung cancer tissues (42.9%). Histologically, it was significantly more frequently expressed in squamous cell carcinoma than in adenocarcinoma (p=0.014). The frequency of precursor CTL in LNL was approximately one in 2.0 x 10(7) in patients with survivin-2B expression (-) lung cancer, however, it was one in 5.0 x 10(6) to 6.0 x 10(6) in those with survivin-2B expression (+) lung cancer. CONCLUSIONS: Survivin-2B was specifically expressed in lung cancer tissue, and found to specifically elicit a cellular immune response in lung cancer patients and therefore it may be a novel candidate for peptide vaccination.

Antigens, Neoplasm↗

PubMed2004

[Tumor marker in primary lung cancer].

Serum tumor markers are non-invasive diagnostic tools for malignant tumor and commonly used for screening of cancer and as an indicator of treatment-effect. In small cell lung cancer, NSE and proGRP are effective markers. In non-small cell lung cancer (NSCLC), CEA, SCC, CYFRA21-1, SLX and CA19-9 are commonly used for screening, and at least one marker among CEA, SCC or CYFRA21-1 is positive in 77% of patients with NSCLC. According to the histological type, the positive rate of CEA and CYFRA21-1 is high in adenocarcinoma patients, and the positive rate of CYFRA21-1 and SCC is high in squamous cell carcinoma patients. This review summarizes the clinical usefulness of tumor markers in primary lung cancer.

Antigens, Neoplasm↗

PubMed2004

Simultaneous cellular and humoral immune response against mutated p53 in a patient with lung cancer.

We recently identified several Ags recognized by tumor-infiltrating B lymphocyte-derived Ab using SCID mice and a xenografted non-small cell lung cancer system. One of these identified Ags was mutated p53 with a point mutation resulting in the alteration of codon 158 from Arg to Leu. The aim of this study was to ascertain whether cellular immunity against mutated p53 exists in the same patient together with humoral immunity. Two different nona peptides (mutated p53(150) and p53(155) peptides), including a mutated amino acid derived from p53, were synthesized according to the binding motif of HLA class I of the established cancer cell line A904L from the patient. Mediastinal lymph node lymphocytes of the patient were stimulated weekly with the peptides. The mutated p53(155) peptide-stimulated lymphocytes showed specific cytotoxicity against both autologous EBV-transformed B cells pulsed with mutated p53(155) peptide and A904L. The mutated p53(155) peptide-specific CTL clone in an HLA-Cw*0702 restriction was established and analyzed for its TCR usage. Clonotypic PCR using CDR3-specific primers was applied to the tumor tissue containing the tumor-infiltrating lymphocytes. The specific amplification of PCR was found in the tumor tissue. These results demonstrated that not only B lymphocytes producing specific Ab against the p53 protein, but also CTL against mutated p53, expressed in autologous lung cancer cells exist in the tumor tissue. This approach may allow us to better understand the mechanisms of T and B cell immunity against the same tumor Ag in cancer patients.

Amino Acid Sequence↗

PubMed2003

Survival and prognostic factors of surgically resected T4 non-small cell lung cancer.

BACKGROUND: Category T4 nonsmall cell lung cancer (NSCLC) encompasses heterogenous subgroups. We retrospectively analyzed the survival of patients with surgically resected T4 NSCLC to evaluate the evidence for prognostic implications according to the subgroups of T4 category, nodal status, and resection completeness. METHODS: Seventy-six patients with T4N0-2M0 NSCLC were divided into three subgroups within the T4 category: 24 patients with the tumor invading the mediastinal organs (mediastinal group), 16 with a malignant pleural effusion or dissemination (pleural group), and 36 with satellite tumor nodules within the ipsilateral primary tumor lobe (satellite group). Complete resection was possible in 47 patients (61.8%). The pathologic N statuses were N0 in 28, N1 in 13, and N2 in 35 patients. RESULTS: The overall survival of the 76 patients was 19.1% at 5 years. The overall 5-year survivals according to the three subgroups of the T4 category were as follows: mediastinal group, 18.2%; pleural group, 0%; and satellite group, 26.7% (mediastinal/satellite versus pleural, p = 0.037). Factors significantly influencing the overall 5-year survival were the pathologic N status (N2 versus N0-1, p = 0.022) and the completeness of resection (complete versus incomplete, p = 0.0001). A multivariate survival analysis demonstrated that the pathologic N status and the completeness of resection were significant independent predictors of a poorer prognosis even after adjusting for the subgroup of the T4 category. CONCLUSIONS: Resectable T4N0-1 NSCLC that is not due to pleural disease deserves consideration of aggressive surgical resection with expected 5-year survival of about 20%.

Adult↗

PubMed2003

Pleomorphic carcinoma: report of a case with massive pleural effusion and asbestos particles.

Pleomorphic (spindle/giant cell) carcinoma (PC) is one subset of large cell carcinoma. It is well known that PC patients have a poor survival rate. This report describes a 68-year-old man with PC. The patient's tumor had a massive pleural effusion. A left lower lobectomy and partial resection of the left diaphragm, peritoneum, and parietal pleura were performed to remove the tumor. Numerous asbestos particles were found in the left lower lobe. This is the first reported case of PC which may have been caused by asbestos particles. Further investigation is needed into whether asbestos exposure causes PC.

Aged↗

PubMed2002

Tumor-infiltrating B lymphocytes as a potential source of identifying tumor antigen in human lung cancer.

Functional studies using freshly isolated tumor-infiltrating B lymphocytes(TIB) are difficult to perform and interpret. Here we document a novel function of TIB using fresh human lung cancer tissues engrafted in SCID mice; they are at activated state and produce tumor-specific antibodies in tumor microenvironment: (a) TIB engrafted in SCID mice produced human IgG; (b) IgG derived from TIB highly bound intracellular and membrane-bound antigens of autologous cancer cells; and (c) less recognition of autoantigens expressed on normal lymphocytes by IgG derived from TIB compared with IgG from the serum of the patient. On the basis of the novel findings presented in this study, we modified the original serological analysis of antigens by recombinant cDNA expression cloning design in a patient with lung cancer who expressed unusually favorable clinical evolution and analyzed humoral immunity against identified mutated p53 antigen. This study provides the first demonstration that antibodies derived from TIB recognize tumor antigens by serological analysis of antigens by recombinant cDNA expression cloning methodology and circulating anti-p53 antibodies in sera derived from TIB in tumor microenvironment. Our approach using TIB may allow the identification of key antigens in the humoral cancer-related immune system.

Animals↗