PubMed Health⌕ Search

Biomedical subjects

Masahiko Tsurumaru

Publications and source records attributed to Masahiko Tsurumaru.

At least 19 recordsLinked to original sources
PubMed2006

Alvocidib (Flavopiridol) suppresses tumor growth in SCID mice with human esophageal cancer xenografts without inducing apoptosis.

Alvocidib (Flavopiridol, HMR1275) is a potent inhibitor of multiple cyclin-dependent kinases and has been identified recently as an antitumor agent in several cancers. Previous studies have shown that alvocidib could potentially treat esophageal cancer in vitro. This study evaluates alvocidib for its ability to suppress tumor growth in severe combined immunodeficiency (SCID) mice bearing TE8 human esophageal squamous cell carcinoma (SCC) xenografts. Alvocidib treatment of 10mg/kg body weight reduced tumor volume significantly. Immunohistochemistry analysis of alvocidib-treated tumor sections showed significant reductions in cyclin D1, VEGF, and Rb levels. Alvocidib treatment did not cause a marked increase in apoptotic tumor cells by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) analysis, yet hematoxylin and eosin staining revealed tumor necrosis. In vivo investigation of alvocidib treatment confirmed antitumor activity in TE8 esophageal xenografts. These findings suggest that alvocidib could be a useful anti-cancer agent for esophageal cancer.

Animals↗
PubMed2006

Birt-Hogg-Dubé (BHD) gene mutations in human gastric cancer with high frequency microsatellite instability.

Birt-Hogg-Dubé (BHD) syndrome is a rare inherited genodermatosis characterized by benign hamartomatous skin lesions and an increased risk of pneumothorax and renal tumors. Many of the patients harbor insertion/deletion mutations in the hypermutable poly(C)(8) tract in exon 11 of the BHD gene. This mutational hot spot is also reported to be a target of mutation in microsatellite instability (MSI) sporadic colorectal tumors. To test if the BHD gene is a potential mutational target in gastric cancer, we screened for mutations in all of the coding exons of the BHD gene in 30 cases of MSI gastric cancer as well as 50 cases of microsatellite stable (MSS) gastric cancer. Mutations in the poly(C)(8) tract of BHD were detected in 3 of 19 MSI-high cases (15.8%), and none of 11 MSI-low cases. All BHD mutated cases also showed mutations of both BAX and TGFbetaRII. No mutations were detected in the other exons of the BHD gene. No BHD mutations were found in MSS gastric cancer cases. Taken together, these findings show that the BHD gene is a rare target in MSI-high gastric cancer, and BHD mutation tends to occur downstream in the mutational events of other major MSI-high target genes.

Adult↗
PubMed2005

Monoclonal antibody to HER-2/neu receptor enhances radiosensitivity of esophageal cancer cell lines expressing HER-2/neu oncoprotein.

PURPOSE: The role of HER-2/neu in the response of esophageal cancer to radiation is not well known. The purpose of this study was to evaluate the effect of an anti-HER-2/neu antibody trastuzumab on the proliferation, cell cycle distribution, and radiosensitivity of esophageal cancer cell lines. EXPERIMENTAL DESIGN: Expression of HER-2/neu protein by four esophageal squamous cancer cell lines (KE4, TE8, TE9, and TE10) and an esophageal adenocarcinoma cell line (SKGT4) was assessed using immunohistochemical (IHC) analysis and flow cytometry. We also evaluated HER-2/neu oncogene expression by fluorescence in situ hybridization. As a control for HER-2/neu protein expression and gene amplification, breast cancer cell lines (MCF7, MDA MB175VII, and SKBR3) were also examined. The cytotoxity of trastuzumab (0.1-200 microg/mL) was estimated by the MTT assay, and the cell cycle distribution was determined by flow cytometry. The effect of 10 microg/mL trastuzumab combined with radiation was assessed by a clonogenic assay. RESULTS: Flow cytometry and IHC revealed that two esophageal cancer cell lines (TE9 and SKGT4) showed HER-2/neu expression (IHC 1+ and mean fluorescence intensity of 11-20), while the other esophageal cancer cell lines were negative for HER-2/neu expression. Although trastuzumab alone had no effect on the esophageal cancer cell lines, the combination of 10 microg/mL trastuzumab with radiation showed a synergistic effect on the HER-2/neu expressing cell lines. CONCLUSIONS: This study suggested that trastuzumab plus irradiation may be effective for the treatment of esophageal cancers, including adenocarcinoma and squamous cell cancer with HER-2/neu expression.

Antibodies, Monoclonal↗
PubMed2005

Gastrointestinal stromal tumor in a child and review of the literature.

Gastrointestinal stromal tumors (GIST) are c-KIT positive neoplasm that occur predominantly in adults. A 13-year-old boy who presented with massive gastrointestinal hemorrhage was subsequently diagnosed with GIST of the stomach. The tumor originated from the lesser curvature with a narrow base and no infiltration into surrounding organs. Two metastatic lesions in the liver were also found. Total excision of the gastric lesion was performed followed by adjuvant imatinib mesylate chemotherapy. He has had no signs of recurrence during 8 months of follow-up. GIST in children are rare and their behavior is notoriously difficult to predict. We report our experience and review the literature.

Adolescent↗
PubMed2005

Frequent trefoil factor 3 (TFF3) overexpression and promoter hypomethylation in mouse and human hepatocellular carcinomas.

Expression profiling analysis revealed ectopic high expression of mouse TFF3 in non-tumor liver tissues from the hepatocellular carcinoma (HCC) susceptible PWK/Rbrc strain. TFF3 is a member of the trefoil factor family peptides, which are small secreted proteins regulating mucosal regeneration and repair, and which are overexpressed during inflammatory processes and cancer progression. We, therefore, analyzed the TFF3 expression extensively in mouse and human HCCs. Expression of the mouse TFF3 gene was significantly increased in 6 out of 7 HCCs from a PWK spontaneous tumor model and in all 7 HCCs from an SV40T antigen-induced transgenic MT-D2C57BL/6 model. In humans, 8 of 20 HCCs (40%) had overexpression of TFF3 in both mRNA level and protein level. We then analyzed DNA methylation patterns of the TFF3 promoter region to evaluate expression regulation of promoter methylation. In mouse HCCs, we demonstrated that two CpGs, at positions -992 and +109, were hypomethylated in 13 of 14 mouse HCCs. In human HCCs, hypomethylation at CpG -260 was associated with TFF3 overexpression (p=0.04). These results indicate that TFF3 overexpression may be a critical process in mouse and human hepatocellular carcinogenesis, and the specific promoter CpG hypomethylation may be one of the regulation mechanisms of TFF3 overexpression in HCCs.

Animals↗
PubMed2005

[Operative technique aiming at en bloc dissection in esophageal surgery].

The lymph node metastases of esophageal cancer occur over a wide area. It is essential for radical surgery of such metastases to aim at en bloc dissection. Otherwise, it can easily become a combination of blunt esophagectomy and lymph node sampling through a right thoracotomy. In the intrathoracic procedure, all the nodes to be dissected can be harvested while attached to the esophagus together with the surrounding connective tissue, except for the pretracheal nodes in front of the cardiac branches of the right vagus nerve and the subaortic arch nodes. It is important to dissect the left paratracheal nodes en bloc, preserving the left recurrent laryngeal nerve. In the abdomen, nodes around the celiac axis and nodes on the common hepatic artery and proximal part of the splenic artery are all removed en bloc with the perigastric nodes in the left gastric arterial basin. The cervical paratracheal and paraesophageal nodes are removed separately from the resected esophagus, but the continuity of dissection can be ensured when the dissection from the neck meets the empty space made by the dissection along the bilateral recurrent laryngeal nerves through the thoracotomy. We believe that such en bloc dissection is the key to improving the long-term results of esophageal cancer surgery.

Esophageal Neoplasms↗
PubMed2004

Loss of heterozygosity analysis shows monoclonal evolution with frequent genetic progression and divergence in esophageal carcinosarcoma.

Carcinosarcoma (spindle cell carcinoma) of the esophagus is a rare neoplasm that shows squamous cell carcinoma (SCC) with a variable component of spindle cell sarcoma. Clinical and pathologic features of this neoplasm have been well documented, but the histogenesis has long been a matter of speculation and dispute. In an attempt to clarify the clonality and genetic relationships in the evolution of this neoplasm, we microdissected a total of 36 carcinomatous and sarcomatous foci from six esophageal carcinosarcoma (CS) and analyzed the allelic status with 25 microsatellite markers on chromosomal arms 3p, 5q, 6q, 8p, 9p, 11q, 13q, 17p, and 18q. In all cases, we found multiple and homogenous allelic losses in both the carcinomatous and sarcomatous components, strongly supporting the concept of monoclonal origin for this neoplasm. Homogeneous allelic losses were detected most frequently on 17p (5 cases), a chromosomal arm that included the p53 locus, followed by 3p, 11q, and 13q (3 cases); 9p (2 cases); and 8p and 18q (1 case). Moreover, five of the six cases showed additional or divergent allelic losses at more than one chromosomal locus at some of the microdissected foci, indicating genetic progression (2 cases) or genetic progression and divergence (3 cases). In four cases, the genetic changes indicated that an original clone of a pure SCC apparently acquired carcinosarcomatous or sarcomatous phenotype by successive genetic changes. On the other hand, we saw no evidence for tumors in which a sarcoma appeared to give rise to a carcinosarcomatous or carcinomatous subclone in the examined cases. In conclusion, our data support the concept that esophageal CS is derived from a single clone originating from a SCC. Furthermore, we showed genetic heterogeneity to accompany the phenotypic divergence, with patterns of genetic alterations that are consistent with both progression and divergence within individual tumors.

Adult↗
PubMed2003

c-erbB-2 oncoprotein expression related to chemoradioresistance in esophageal squamous cell carcinoma.

PURPOSE: Esophageal carcinoma is a challenging target for radiotherapy. To improve treatment efficacy, an investigation of a predictive factor is desirable. In this study, we evaluated the significance of apoptosis and immunohistochemical staining for p53, Ki-67, c-erbB-2 (HER-2/neu), Ku (p70/p80), and DNA-PKcs for predictive markers of the responsiveness to chemoradiotherapy in esophageal squamous cell carcinoma. MATERIALS AND METHODS: This retrospective analysis consisted of 34 patients with esophageal squamous cell carcinoma in whom tumor biopsy was performed before treatment. They were divided into chemoradiosensitive (n = 13) and chemoradioresistant (n = 21) groups according to the tumor response evaluated at a total radiation dose of 40 Gy. The biopsy samples were examined with immunohistochemical staining for various factors and with an in situ nick end labeling method for apoptosis. The examined data were compared between the two groups. RESULTS: The difference in the Ki-67, p53, Ku (p70/p80), DNA-PKcs labeling indexes and the apoptosis index in tumor cells between the chemoradiosensitive and chemoradioresistant groups was not statistically significant. The expression of c-erbB-2 oncoprotein was statistically significant in the chemoradioresistant group (p = 0.02), although it did not correlate with survival. CONCLUSIONS: c-erbB-2 immunostaining is useful for the prediction of chemoradioresistance in esophageal squamous cell carcinoma.

Adult↗
PubMed2003

[Surgical treatment for esophageal cancer in elderly patients over 75 years of age].

UNLABELLED: We performed 127 esophageal resections for the esophageal cancer patient from December 1995 to September 2001. It was separated to under 70 years old patients group (group I), 71-74 years old patients group (group II), and over 75 years old patients group (group III). RESULTS: Postoperative complication was occurred in 53 cases (41.7%) within all of 127 esophageal resected cases. It was 33.7% in group I, 53.6% in group II, 62.5% in group III. Four years survival rate of each group is 38.3% in group I, 44.6% in group II, 31.3% in group III. It is significantly better in group II rather than in group III. Operative death rate is 12.5% (2 cases) in group III, 7.1% (2 cases) in group II, 3.6% (3 cases) in group I, and it is gradually higher and higher by patient's age. CONCLUSIONS: (1) In the esophageal cancer patient over 75 years old, postoperative complication rate is higher than under 74 years old patients, and prognosis is significantly poor rather than in 70-74 years old patients group. (2) In the esophageal cancer patient over 75 years old, we considered it is good indication of esophagectomy for stage I and stage II patient without preoperative complication, however, there are no operative indication for stage III and stage IV patient.

Age Factors↗
PubMed2003

[Controversies in esophageal cancer surgery].

In esophageal cancer treatment, the choice of treatment modality and the indications and extent of lymph node dissection surgery are controversial. In terms of the biological characteristics, esophageal cancer is more virulent than any other gastrointestinal malignancy. The distribution of lymph node metastases is very wide, extending from the neck to abdominal regions, and the sizes of lymph node metastases are very small. Almost two-thirds of all metastatic lymph nodes showed minute metastases less than 5 mm in diameter. In patients with superficial cancer with only submucosal invasion, lymph nodes metastases were found in both the upper mediastinal and paracardial areas in up to 27% cases. Furthermore, the accuracy of preoperative diagnosis of lymph node metastasis in esophageal cancer is still unsatisfactory. False negative rates in preoperative diagnosis of lymph node metastases are 14% in the neck area, 36% in the mediastinal area, and 34% in the abdominal area. Therefore, in order to cure esophageal cancer by surgery, wide, precise and complete removal of possible metastatic lymph nodes is essential. It is at this time that the quality assurance of surgery is indispensable in reducing morbidity and mortality, and in improving the patient survival. Because both surgery and chemoradiotherapy are local treatments, we must recognize the limitation of these therapeutic modalities. To improve overall survival of esophageal cancer patients, we have to make a more concentrated effort toward the systemic control of this disease.

Contraindications↗
PubMed2003

[Surgery for benign submucosal tumors of the esophagus (leiomyoma and hemangioma)].

Among the submucosal tumors of the esophagus, leiomyoma is the most frequently found. Esophageal leiomyoma usually originates from the muscle layer of the esophageal wall and grows spirally around the esophageal axis. In the surgical treatment of leiomyoma, we enucleate the tumor through video-assisted thoracic surgery. When we enucleate leiomyoma, we must be very careful to aviod perforation of the esophageal mucosa. Esophageal hemangioma is a relatively rare disease. The location of this disease is mainly within the submucosal layer, without invading the muscle layer proper. After confirming the localization within the mucosa or submucosa with endoscopic ultrasonography, esophageal hemangioma can be resected safely using the endoscopic mucosal resection technique. In the treatment of benign esophageal submucosal tumors, "informed consent" is as essential as in esophageal cancer surgery. We have no absolute criteria concerning the indications for surgery for benign esophageal submucosal tumors. We must give reasons why the operation is necessary and indicated to the patients. Surgical treatment of esophageal submucosal tumors should be as minimally invasive as possible.

Endosonography↗
PubMed2002

A case of fibromatosis of the breast.

A 36-year-old woman presented with a 10 mm diameter mass in the right breast. Since the mass persisted for 3 months after detection and mammary carcinoma was suspected based on ultrasonographic findings, the mass was resected. Histologically, the mass demonstrated proliferative margins and consisted of spindle cells with bland cytologic features and abundant collagen. Immunohistochemically, the spindle cells were positive for vimentin and smooth muscle actin, and were negative for cytokeratins and desmin. Furthermore, the cells showed MIB-1 immunoreactivity with a MIB-1 labeling index of 4.1. Based on these findings, was diagnosed fibromatosis. Breast fibromatosis is rare and is usually misdiagnosed as breast carcinoma preoperatively. To date, only 10 cases of breast fibromatosis have been reported in Japan. Among the reported cases in Japan, our patient presented with the smallest mass, and ultrasonographic findings in this case were the same as those of other cases. Our experience and a review of the literature indicated that differentiation of fibromatosis from carcinoma is very difficult by ultrasonographic examination. In our case, despite involvement of the surgical margins, there was no recurrence. This may be attributed to the small size of the mass and focal exposure.

Adenocarcinoma↗