Biomedical subjects

H Ayabe

Publications and source records attributed to H Ayabe.

At least 19 recordsLinked to original sources

PubMed2003

Immunohistochemical expression of E-cadherin in metastatic brain tumors.

The adhesion molecule E-cadherin has been shown to influence malignant transformation of tumors, including local and distant metastases. We examined the expression of E-cadherin to determine its relationship to the development of metastasis in metastatic brain tumors. Immunohistochemistry for E-cadherin and Ki-67 was carried out in 76 formalin-fixed, paraffin-embedded archival specimens of metastatic brain tumors and in 14 corresponding available primary tumors from patients who received treatment for metastatic brain tumors. The primary tumors were mainly lung cancers (51.3%), followed by gastrointestinal tumors (28.9%). E-cadherin was expressed in 62 (81.5%) of 76 cases examined. In metastatic adenocarcinomas, a consistent tendency for E-cadherin expression was noted, regardless of the degree of differentiation or the extent of spread of the disease (P = 0.04). There was a direct correlation between E-cadherin expression and high MIB-1 index in all metastatic brain tumors (P = 0.0007). Pairwise analysis in 14 primary tumors and the corresponding metastatic specimens revealed high E-cadherin and MIB-1 staining in metastatic brain tumors. These results provide a unique association between E-cadherin, systemic metastasis, and proliferation potential in metastatic brain tumors.

Adenocarcinoma↗

PubMed2003

Chromosomal imbalances associated with acquired resistance to fluoropyrimidines in human colorectal cancer cells.

The chromosomal aberrations underlying the development of resistance to fluoropyrimidines have not yet been identified. To characterise the genomic changes that induce the development of resistance to fluoropyrimidines, we used comparative genomic hybridisation (CGH) to analyse and compare the parent DLD-1 human colorectal cancer cell line and two cell lines, DLD-1/5-FU and DLD-1/FdUrd, which were resistant to 5-fluorouracil (5-FU) and 5-fluoro-2'-deoxyuridine (FdUrd), respectively. Both resistant cell lines showed a genetic aberration derived from the parental cell line DLD-1. Losses of 3p and 3q were also detected as additional genetic changes in the two resistant cell lines. Both resistant cell lines showed decreased orotate phosphoribosyltransferase (OPRT) activity, which is associated with the activity of the uridine monophosphate (UMP) synthase gene (3q13). These results suggested that the loss of 3q might be a genetic change responsible for the decreased OPRT activity and fluoropyrimidine cytotoxic response in cancer cells. Amplification of 18p11.2-p11.3 containing the thymidine synthase (TS) gene (18p11.32) was observed only in the DLD-1/FdUrd-resistant cell line, which overexpresses TS. These findings suggested that 18p amplification represents a genetic change associated with the overexpression of the TS protein. Our results indicate that chromosomal aberrations identified by CGH could explain, at least in part, acquired fluoropyrimidine resistance.

Antimetabolites, Antineoplastic↗

PubMed2003

Long-term outcomes of intragastric endoscopic mucosal resection using a modified buess technique for early gastric cancer.

BACKGROUND/AIMS: The aim of this study was to clarify long-term outcomes of endoscopic mucosal resection (EMR) using a modified Buess technique for mucosal gastric cancer. METHODS: The procedure included en bloc mucosal resection using a Buess-type rectoscope into the gastric lumen via a temporary gastrostomy under video camera guidance. We reviewed 5 patients who underwent this procedure between 1995 and 1997 with a single mucosal cancer of the stomach that was unsuitable for en bloc excision by endoscopic snare diathermy. RESULTS: All tumors were superficial elevated types (type 0-IIa) located in the middle third and posterior wall of the stomach. Median maximum tumor diameter was 2.2 (range 1.1-3.5) cm. There was no operative mortality. One patient developed a hemorrhagic gastric ulcer postoperatively. All tumors histologically showed curative potential of the mucosal resection without margin involvement. During a median follow-up period of 64 (50-77) months, none of the patients developed local recurrence. One patient had an early gastric cancer that metachronously developed at another stomach site. CONCLUSION: Intragastric EMR using a modified Buess technique appears to be a useful treatment for cure of mucosal gastric cancer for a limited group of patients unsuitable for complete en bloc excision by endoscopic snare diathermy.

Adenocarcinoma↗

PubMed2002

Expression of ABH/Lewis-related antigens as prognostic factors in patients with breast cancer.

PURPOSE: The prognostic value of altered blood group factor and Lewis-related carbohydrate antigen expression in breast cancers has not been fully determined. METHODS: To this end, breast carcinoma samples from 87 radical mastectomy patients with primary cancer were analyzed by immunohistochemistry for the ABH factors, Le(a), sialyl Le(a), Le(x), and sialyl Le(x). RESULTS: It was found that ABH, Le(a), sialyl Le(a), Le(x), and sialyl Le(x) antigens were expressed in 25 (21.8%), 26 (22.6%), 26 (22.6%), 36 (31.3%), and 37 specimens (32.2%), respectively. Tumors with lymph node metastasis expressed Le(x) or sialyl Le(x) antigens more frequently than those without lymph node metastasis ( P=0.0020 or P=0.039, respectively). The survival time of patient s after surgery was significantly shorter for those whose tumors expressed Le(x) or sialyl Le(x) than for those without Le(x)- or sialyl Le(x)-positive tumors ( P=0.0028 and P=0.0029, respectively). Cox's multiple regression analysis revealed that sialyl Le(x) expression was an independent prognostic factor for patient survival regardless of primary tumor (T factor) and lymph node (N factor) status (hazards ratio, 3.80). CONCLUSIONS: Thus, expression of sialyl Le(x) antigen in tumor cells is associated with poor prognosis in patients with breast cancer and must be considered in the design of future therapeutic trials.

ABO Blood-Group System↗

PubMed2002

Surgical technique and outcome of gasless video endoscopic transanal rectal tumour excision.

BACKGROUND: Transanal endoscopic microsurgery (TEM) is unpopular because of its high cost and most surgeons' unfamiliarity with microscopic surgery. This report describes an experience with a modification of TEM, gasless video endoscopic transanal rectal tumour excision (gasless VTEM), which incorporates a standard laparoscopic video camera and requires no carbon dioxide insufflation system. METHODS: One hundred and one patients with 105 rectal tumours underwent gasless VTEM between 1993 and 2000. RESULTS: Histological examination revealed 18 adenomas, 75 carcinomas (Tis, 47; T1, 23; T2, five), 11 carcinoid tumours and one lymphoma. The median height above the dentate line and maximum tumour diameter was 5.0 (range 2-14) cm and 2.0 (range 0.4-8.0) cm respectively. The peritoneal cavity was opened intraoperatively in two patients. The median operating time was 53 (range 15-202) min. Bleeding, suture dehiscence and transient incontinence developed after operation in four patients. There was no operative death. Median hospital stay was 5 (range 1-21) days. Eleven patients with T1/T2 staging underwent subsequent radical resection. The median duration of follow-up was 52.3 months. One patient with a carcinoma developed a recurrence. CONCLUSION: Gasless VTEM is a feasible, safe and minimally invasive procedure for the treatment of selected rectal adenomas and early carcinomas. The suggested modifications may make the procedure more widely available.

Adenocarcinoma↗

PubMed2002

Tie-2 and angiopoietin-1 expression in human thyroid tumors.

Tie-2 is an endothelial cell-specific receptor tyrosine kinase involved in vascular maturation and remodeling. Although its expression is considered to be restricted to vascular endothelial cells and hematopoietic progenitors, our immunohistochemical and in situ hybridization studies showed that Tie-2 and its ligand, angiopoietin (Ang)-l were expressed not only in benign and malignant human thyroid tumor cells but also in hyperplastic regions of adenomatous goiter. To confirm the expression in these tissues further, we used a laser capture microdissection system to isolate epithelial tumor cells from tissue specimens selectively, and demonstrated the expression of Tie-2 and Ang-1 mRNAs in tumor cells by RT-PCR analysis. Furthermore, Tie-2 and Ang-1 mRNAs and proteins were also detected in rat thyroid cell lines, FRTL-5 and PCCL-3. Our results suggest that Ang-1/Tie-2 signaling may be involved in the proliferation of thyroid epithelial cells.

Adenocarcinoma, Follicular↗

PubMed2002

Evaluation of sialyl Lewis(a), sialyl Lewis(x), and sialyl Tn antigens expression levels as predictors of recurrence after curative surgery in node-negative colorectal cancer patients.

This study aimed to determine whether sialyl Lewis(a) (Le(a)), sialyl Lewis(x )(Le(x)), or sialyl Tn antigen expression could identify a subset of node-negative colorectal cancer patients that are at high risk for recurrence after curative surgery. Tumor tissue samples from 90 patients with node-negative colorectal cancer, who had undergone surgical resection, were analyzed immunohistochemically for the expression of each antigen. Patients were classified as having low or high antigen expression depending on whether more or less than 40% of the field showed positive staining. The main outcome measure for each variable was disease-free interval. Sialyl Le(a), sialyl Le(x), and sialyl Tn antigens were expressed in 53 (58.9%), 41 (45.6%), and 34 (37.8%) carcinomas, respectively. The median follow-up was 83.5 months. Patients with high sialyl Le(x) expression had shorter disease-free intervals than those with low sialyl Le(x) expression (P = 0.0041); the expression of sialyl Le(a) or sialyl Tn antigens did not show a significant relationship with disease-free survival. Cox's regression analysis revealed that sialyl Le(x) expression was an independent predictor for disease-free survival, separate from T factor or tumor location. High sialyl Le(x) expression may be useful in identifying a subset of node-negative colorectal cancer patients who are at high risk for recurrence.

Adult↗

PubMed2002

Increased expression of sialyl Lewis(x) antigen in penetrating growth type A early gastric cancer.

Early gastric cancer can be divided morphologically into two categories, penetrating growth type-A (Pen-A type) and other growth types (non-Pen-A types). Sialyl Lewis(x) antigen has been demonstrated to play an important role in tumor metastasis by serving as a functional ligand in the cell adhesion system. The aim of this study is to ascertain whether or not sialyl Le(x) antigen expression correlates with tumor growth patterns of early gastric carcinoma. An immunohistochemical assay was performed using monoclonal antibody CSLEX1 in 12 Pen-A type and 79 non-Pen-A type cancers. Scoring was based on the percentage of immunoreactive cells: negative, low expression (< or = 25%), and high expression (> 25%). Lymph node metastasis was found more frequently in Pen-A type than non-Pen-A type cancers (P=0.0004). Furthermore, sialyl Le(x) antigen high expression was detected more often in Pen-A type cancers (7 out of 12; 58.3%) than non-Pen-A type cancers (13 out of 79; 16.5%) (P=0.0036). Multivariate logistic regression analysis showed that these variables are related independently to the Pen-A type and the non-Pen-A type tumor growth patterns. These data suggest that the difference in sialyl Le(x) antigen expression between the Pen-A type and non-Pen-A type tumor growth patterns of early gastric cancer may, at least partially, reflect different biological behavior during tumor progression.

Adenocarcinoma↗

PubMed2001

PKC delta mediates ionizing radiation-induced activation of c-Jun NH(2)-terminal kinase through MKK7 in human thyroid cells.

The thyroid gland is one of the most sensitive organs in ionizing radiation (IR)-induced carcinogenesis. To determine, therefore, the specific cascade of IR-induced signal transduction in human thyroid cells, we investigated the functional role of protein kinase C (PKC), especially its interlocking activation of c-Jun NH(2)-terminal kinase (JNK) pathway. In the present study, using adenovirus expression vectors for diverse dominant-negative (DN) types of PKC isoforms (alpha, beta2, delta, epsilon and zeta) expressed in primary cultured human thyroid cells, only DN/PKC delta suppressed IR-induced JNK activation. In addition, Rottlerin, a PKC delta specific inhibitor, inhibited IR-induced JNK activation. IR-induced activation of transcription factor AP-1, downstream target of JNK, was also attenuated by DN/PKC delta. To examine the involvement of upstream kinases of JNK, we performed immune-complex kinase assays of mitogen-activated protein kinase kinase 4 (MKK4) and MKK7. IR activated MKK7 but not MKK4, and this activation was inhibited by Rottlerin. Furthermore, IR-induced JNK activation was suppressed by overexpression of kinase-deficient MKK7. Our results indicate that IR selectively activates the cascade of PKC delta-MKK7-JNK-AP-1 in human thyroid cells, suggesting a not apoptotic but radio-resistant role of PKC delta in human thyroid cells following IR.

Enzyme Activation↗

PubMed2001

Completion pneumonectomy for recurrent or second primary lung cancer.

OBJECTIVE: We studied 8 patients undergoing completion pneumonectomy for recurrent or second primary lung cancer. METHODS: Subjects were men who averaged 62 years of age. Of these 6 had p-stage I, and 2 p-stage II disease at initial operation. At the second operation, we diagnosed 3 with second primary lung cancer and 5 with recurrent lung cancer. We predicted postoperative pulmonary function by calculating the predicted forced expiratory volume in 1.0 second (FEV1.0) from residual numbers of subsegments after completion pneumonectomy. All predicted FEV1.0 in our 8 cases ranged from 544 to 926 (773 +/- 144) ml/m2. RESULTS: Six patients experienced postoperative complications and morbidity was 75%. One patient undergoing completion sleeve pneumonectomy after radiation therapy for local carina recurrence died on 7th postoperative day due to anastomotic dehiscence and pneumonia. Overall operative mortality was 12.5% (1/8). Four remain alive and actuarial 5-year survival was 37.5%. CONCLUSIONS: Careful consideration is needed in determining operative indications for completion pneumonectomy for patients after radiation therapy. Patients with recurrent squamous cell carcinoma who have p-stage I disease at initial operation and those with second primary lung cancer and p-stage I or II disease can expect relatively a long-term survival, and we concluded that completion pneumonectomy could be conducted in these cases with a satisfactory prognosis.

Adenocarcinoma↗

PubMed2001

Circulating sialyl Lewis(x), sialyl Lewis(a), and sialyl Tn antigens in colorectal cancer patients: multivariate analysis of predictive factors for serum antigen levels.

Preoperative serum levels of sialyl Lewis(a) (CA 19-9), sialyl Lewis(x) (SLX), and sialyl Tn (STN) antigens in colorectal cancer patients were examined to establish predictive factors for serum levels of these antigens compared with carcinoembryonic antigen (CEA). A total of 308 patients who underwent resection for a colorectal cancer were divided into low and high antigen groups (higher or lower than a selected diagnostic-based cutoff value). The cutoff values were 37 U/ml for CA19-9, 38 U/ml for SLX, 45 U/ml for STN, and 2.5 ng/ml for CEA. The American Joint Committee on Cancer Classification and Stage grouping was used to classify the tumors. Statistical tests were conducted using univariate and multivariate logistic regression analyses. For CA19-9, 81 patients (26.3%) were assigned to the high antigen group: for SLX, 39 (12.7%); for STN, 33 (10.7%); and for CEA, 133 (43.2%). Multivariate logistic regression analysis revealed that predictive factors associated with high antigen levels were female sex (odds ratio [OR], 1.78 vs male sex), T4 (OR, 3.26 vs T1/T2), and M1 (OR, 3.35 vs M0) for CA19-9; M1 (OR, 6.40 vs M0) for SLX; mucinous carcinoma (OR, 8.45 vs well differentiated adenocarcinoma) and M1 (OR, 8.24 vs M0) for STN; and mucinous carcinoma (OR, 7.21 vs well differentiated adenocarcinoma), T3/T4 (OR, 3.84/4.18, respectively, vs T1/T2), and M1 (OR, 6.39 vs M0) for CEA. In conclusion, high serum levels of CA19-9, SLX, and STN are strongly associated with distant metastasis. In addition, high serum levels of CA19-9 may be an independent predictor for female gender and T4, and high serum levels of STN may be an independent predictor for mucinous carcinoma.

Aged↗

PubMed2001

Minilaparotomy wound edge protector (Lap-Protector): a new device.

Laparoscopic-assisted or minimally invasive surgery involving minilaparotomy is occasionally complicated by infection of the minilaparotomy wound caused by intestinal bacteria. Furthermore, when this procedure is performed to excise colorectal or gastric cancer, tumor recurrence may develop in the minilaparotomy wound. In an attempt to minimize the risk of these complications, we developed a new, easy-to-use device which we named the "Lap-Protector." Minilaparotomy was performed using the Lap-Protector in 28 patients with colon cancer and eight patients with early gastric cancer who underwent minimally invasive surgery between January and September, 1999. During a median follow-up period of 15.9 (range 12.4-21.0) months, none of the 36 patients showed any sign of wound infection or tumor recurrence in the minilaparotomy wound. These results indicated that the Lap-Protector is a safe and useful device that may help to prevent infections and cancer cell contamination of the minilaparotomy wound.

Aged↗

PubMed2001

The importance of peripheral blood leukocytes and macrophage infiltration on bronchial wall wound healing in rats treated preoperatively with anticancer agents.

Preoperative chemotherapy is commonly used for small cell lung cancer or advanced non-small cell lung cancer. This study was conducted to investigate the effects of preoperative antineoplastic agents on the postoperative would healing of bronchial anastomoses in a rat model. Cisplatin (CDDP), doxorubicin (ADM), or cyclophosphamide (CPA) was administered either 3 days preoperatively (experiment 1) or 7 days preoperatively (experiment 2). Wound healing was assessed on postoperative days (POD) 3, 5, and 7 after anastomosis of the bronchus, by examining the bursting strength and hydroxyproline tissue content. In experiment 1, significant impairment of wound healing was seen on POD 3 in the CPA-treated rats, but no significant changes were seen in the other groups. Severe leukopenia and marked reduction of macrophage infiltration into the wound were also observed in the CPA-treated rats. The impairment of wound healing coincided with the time of leukopenia and reduced macrophage infiltration into the wounds. In experiment 2, induction chemotherapy did not impair wound healing. Our experimental results suggest that preoperative chemotherapy producing mild leukopenia, or when followed by a sufficient interval to allow for the recovery of myelosuppression, did not impair wound healing of the bronchial anastomoses. The findings of this study also showed that the depletion of macrophages at the anastomotic site is one of the most important causes of impaired wound healing.

Anastomosis, Surgical↗

PubMed2001

Surgical treatment and subsequent outcome of patients with carcinoma of the splenic flexure.

Extended resection, comprising extended right hemicolectomy, splenectomy, and distal pancreatectomy, has been advocated for carcinoma of the splenic flexure because the lymphatic drainage at this site is variable. The present study addresses the problems associated with selecting the most appropriate operative procedure to achieve cure of splenic flexure cancers. We conducted a retrospective review of 27 patients with splenic flexure cancer who underwent curative resection. Left partial colectomy was performed in 20 patients and partial resection of the transverse/descending colon was performed in 7 patients. The combined resection of adjacent organs due to tumor adherence was performed in three patients. The spleen and distal pancreas were the organs most frequently resected among a collective total of six adjacent organs. The median duration of follow-up was 60.9 months after resection for splenic flexure cancer. No patient developed local recurrence. There was no significant difference in 5-year survival between patients with splenic flexure cancers and those with colon cancers at other sites. In conclusion, splenic flexure cancer resected by left partial colectomy or partial resection of the transverse/descending colon without routine extended resection was not associated with a worse prognosis than colon cancers at other sites.

Adenocarcinoma↗

PubMed2001

Evaluation of metastatic potential of gastric tumors by staining for proliferating cell nuclear antigen and chromosome 17 numerical aberrations.

BACKGROUND: Aberrations in chromosome 17 are important in carcinogenesis. We recently reported that numerical aberrations in chromosome 17 were associated with tumor progression in gastric cancer. The aim of this study was to determine the biological characteristics of gastric tumor cells with chromosome 17 numerical aberrations. METHODS: Gastric tumor sections (n = 105) and metastatic lymph nodes (n = 16) were stained simultaneously for PCNA (proliferating cell nuclear antigen) and chromosome 17 centromere. Cancers were classified as follows: Group 1: PCNA(+) and numerical chromosomal aberration(+); Group 2: PCNA(-) and numerical chromosomal aberration(+); Group 3: PCNA(+) and numerical chromosomal aberration(-); and Group 4: PCNA(-) and numerical chromosomal aberration(-). RESULTS: The frequency of Group 1 cells correlated with lymphatic invasion (P < .0001), lymph node metastasis (P < .0001), and venous invasion (P < .01). The frequency of these cells in gastric lesions was lower than in metastatic lymph nodes (P < .01). Logistic regression analysis identified the depth of invasion followed by the frequency of Group 1 cells were two of the most significant independent factors that could predict lymph node metastasis and lymphatic invasion. CONCLUSIONS: The frequency of gastric tumor cells positive for PCNA and chromosome 17 numerical aberrations may be an indicator of the metastatic potential of gastric cancers.

Adult↗

PubMed2001

Colectomy for colon cancer via a 7-cm minilaparotomy.

We herein describe our technique for performing a colectomy to resect colon cancer via a 7-cm minilaparotomy using conventional surgical techniques and instruments. By moving the minilaparotomy wound laterally as well as either caudad or cephalad, the mobilization of the relevant segment of the bowel loop was thus made possible. To ensure an adequate visualization of the operative field during a dissection of the lymph nodes, an Omni-Tract retractor system was used. The division of the colonic mesentery, transection of the affected bowel, and bowel anastomosis were performed extracorporeally or at the level of the incision. This same operation was successfully performed in 102 patients with colon cancer. We conclude that a colectomy for colon cancer via a 7-cm minilaparotomy is an attractive alternative to a conventional full laparotomy in selected patients.

Colectomy↗

PubMed2001

Prolonged survival of rat cardiac allograft with proinflammatory cytokine inhibitor.

BACKGROUND: Proinflammatory cytokines, such as tumor necrosis factor (TNF-alpha) and interleukin-1 (IL-1), play important roles in acute allograft rejection. FR167653 is an inhibitor of these cytokines that acts through inhibition of the mitogen-activated protein kinase p38 pathway. We examined the effect of FR167653 on allograft rejection. METHODS: We used Brown-Norway and Lewis rats as donors and recipients, respectively. We performed heterotopic cardiac transplantation. The control group consisted of untreated rats. In the experimental groups, recipients were intraperitoneally injected with FR167653 just after operation, followed by daily injection of the drug from Day 1 to 10. We divided 20 rats into 5 groups, which received varying doses of FR167653, ranging from 75 to 300 mg/kg/day. RESULTS: In the control group, the mean graft survival was 6.8 +/- 0.3 days. FR167653 at 150 mg/kg/day significantly prolonged the survival period (up to 12.1 +/- 1.5 days, p = 0.002). Histologically, FR167653 markedly suppressed cellular infiltration on Day 5 post-transplantation. The serum level of TNF-alpha in the control group was persistently elevated from 9.3 +/- 3.9 pg/ml to 11.3 +/- 3.8 pg/ml, whereas FR167653 significantly suppressed the level to <1.4 +/- 1.4 pg/ml. CONCLUSIONS: FR167653 prolonged rat cardiac allograft survival by suppressing the action of proinflammatory cytokines.

Animals↗

PubMed2001

Prognostic factors in hepatic metastases of colorectal carcinoma: immunohistochemical analysis of tumor biological factors.

The present study was designed to provide a systemic analysis of prognosis in 62 patients who underwent hepatic resection for colorectal liver metastasis. The analyzed factors included microvessel counts stained by CD34 and expression of two adhesion molecules, E-cadherin and CD44 variant exon 6-(v6) in these tumors. No significant factors related to recurrence were identified and only negative expression of CD44v6 tended to correlate with recurrence (P = 0.075). A short disease-free period to recurrence was noted in patients with high CEA levels (>10 ng/ml) and H2/3 classification. A short surgical margin, H2/3 classification, high microvessel counts (>60/field, x200), and negative expression of CD44v6 and E-cadherin tended to be associated with poor prognosis. A high microvessel count was the most significant prognostic factor by multivariate Cox proportional hazards regression model. Hepatic resection without tumor exposure and a careful follow-up in cases identified with poor prognostic factors are necessary.

Adult↗