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21.
BACKGROUND: Induction of unresponsiveness to graft is one of major interest in xenotransplantation. Two different modalities [direct graft treatment by mitomycin C (MMC) and blockage of the lymphocyte function-associated antigen-1/intracellular adhesion molecule-1 (LFA-1/ICAM-1) pathway in recipients by species-specific mAbs] were tested for their ability to produce unresponsiveness to secondary islet xenografts. METHODS: Collagenase-digested WS (RT1k) rat islets, purified by Ficoll density gradient, were incubated for 30 min with MMC 10 microg/ml, cultured for 20 hr, and transplanted into the renal subcapsular space of streptozotocin-induced diabetic C57BL/6 (H-2b) mice. Recipient mice were divided into experimental groups according to anti-rat ICAM-1 and/or anti-mouse LFA-1 mAb treatment and transplantation of MMC-treated or nontreated islets. RESULTS: MMC pretreatment alone prolonged graft survival, with a mean survival time (MST) of 23.0+/-7.4 days, compared with that of cultured islets (12.4+/-2.7 days; P<0.01). MMC treatment of islets significantly augmented graft survival, compared with that of crude islet grafts under treatment with anti-donor ICAM-1 mAb (MST: >41.3+/-30 vs. 16.6+/-5.4 days, P<0.01), anti-recipient LFA-mAb (MST: >70.3+/-28.9 vs. 30.4+/-10.4 days, P<0.001), or both mAbs (MST: >88.1+/-24.1 vs. 23+/-7.4 days, P<0.0001). One of six, four of nine, and six of eight animals accepted MMC-treated islet xenografts over 100 days after treatment with anti-rat ICAM-1, anti-mouse LFA-1, or both mAbs treatments, respectively, whereas none of the animals accepted nontreated islets under the same treatment. When the mice bearing long-term functioning xenografts were challenged with the secondary graft from the original donor strain, the animals previously treated with anti-recipient LFA-1 and anti-donor ICAM-1 mAbs were more prone to accept it than animals given anti-recipient LFA-1 mAb alone (MST: 55.8+/-25.7 vs. 15+/-2.4 respectively; P<0.001), although they rejected the third-party xenograft and allograft acutely. CONCLUSIONS: In the xenogeneic islet transplantation model, MMC graft pretreatment and blockage of the ICAM-1/LFA-1 pathway constitute a potent protocol for inducing unresponsiveness to islet xenografts.  相似文献   
22.
PURPOSE: Valosin-containing protein (VCP; also known as p97) was shown to be associated with antiapoptotic function and metastasis via activation of nuclear factor kappa-B signaling pathway. In this study, association of VCP expression with recurrence of gastric carcinoma (GC), in which lymphatic vessels are the main route of spread, was examined. PATIENTS AND METHODS: VCP expression in 330 patients with GC (242 males and 88 females) with ages ranging from 26 to 81 years (median, 60 years) was analyzed by immunohistochemistry, in which staining intensity in tumor cells was categorized as weaker (level 1) or equal to or stronger (level 2) than that in endothelial cells. RESULTS: Ninety-four (28.7%) patient cases showed level 1 and 233 patient cases (71.3%) showed level 2 VCP expression. Patients with level 2 expression showed higher rates of large tumor size (P <.0001), undifferentiated histologic subtype (P <.05), presence of vascular and lymphatic invasion (P <.0001 for both), presence of lymph node metastasis (P <.0001), deep tumor invasion (P <.0001), and poorer disease-free and overall survivals (P <.0001 for both) compared with those with level 1 VCP expression. Multivariate analysis revealed VCP expression level as an independent prognosticator for disease-free and overall survival. VCP level was an indicator for disease-free and overall survival in the early (pT1; P <.01 and P <.05, respectively) and advanced (pT2-4; P <.05 for both) group of pathologic tumor-node-metastasis system classification. CONCLUSION: The prognostic significance of VCP expression level in GC was demonstrated.  相似文献   
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PURPOSE: We compared the therapeutic usefulness of doxifluridine (5'-DFUR) alone and a combination of 5'-DFUR plus cyclophosphamide (CPM), both of which are considered effective against advanced and recurrent breast cancer, to determine which treatment is more beneficial as postoperative adjuvant chemotherapy. PATIENTS AND METHODS: A total of 1,131 women with node-positive primary breast cancer were randomly assigned after primary surgery to receive 5'-DFUR alone or 5'-DFUR plus CPM. All patients initially received 5'-DFUR in an oral dose of 1,200 mg/d for 4 weeks, starting 4 weeks after surgery. Chemotherapy was then not given for 2 weeks. Patients in the 5'-DFUR group subsequently received five 4-week cycles of treatment consisting of oral 5'-DFUR (1,200 mg/d) for the first 2 weeks and no chemotherapy for the next 2 weeks. Those assigned to the 5'-DFUR plus CPM group also received oral CPM 100 mg/d for the first 2 weeks and no chemotherapy for the next 2 weeks. Women 50 years or older concurrently received 20 mg/d of tamoxifen for 2 years in both groups. RESULTS: Of the 1,088 eligible women, 546 were assigned to receive 5'-DFUR alone and 542 were assigned to receive 5'-DFUR plus CPM. Overall disease-free survival was significantly better in women who received 5'-DFUR plus CPM than in those who received 5'-DFUR alone (log-rank test, P =.021). Toxic effects occurred in 20.0% of patients (109 of 546) in the 5'-DFUR group and 32.3% of patients (175 of 542) in the 5'-DFUR plus CPM group (chi(2) test, P <.001). CONCLUSION: Combination therapy with 5'-DFUR plus CPM is more effective in preventing recurrence than 5'-DFUR alone.  相似文献   
25.
PURPOSE: Loss of function or expression of the mismatch repair gene MLH1 has been implicated in experimentally acquired resistance to cisplatin (CDDP) and other anticancer agents. The clinical significance of MLH1 expression was evaluated in advanced thoracic squamous cell carcinoma of the esophagus (ESCC) treated by neoadjuvant chemotherapy. EXPERIMENTAL DESIGN: We investigated MLH1 and P53 expression by immunohistochemistry in the surgical specimens of 107 patients who had undergone preoperative chemotherapy using CDDP along with 5-FU and ADM. These findings were correlated with the clinical outcome for this treatment. Biopsy samples before chemotherapy in 20 of these patients, and another 43 surgical specimens without chemotherapy, were also examined as control samples. RESULTS: In surgical specimens of ESCC, low MLH1 expression was not frequent without chemotherapy, whereas it was commonly observed after chemotherapy (14 versus 37%, P = 0.0057). Comparison between samples before and after chemotherapy revealed that MLH1 expression was unchanged during chemotherapy in 12 of 20 patients (60%) but was from high to low in 8 of 20 patients (40%). In the surgical specimen after neoadjuvant chemotherapy, MLH1 expression was not correlated with any clinicopathological factors, including the response to chemotherapy. However, low MLH1 showed poorer prognosis than high MLH1 (5-year survival 40.6 versus 19.3%, P = 0.0393), and in multivariate analysis, MLH1 was an independent prognostic factor for this multimodal treatment, following lymph node metastasis and clinical response to chemotherapy. Positive p53 expression, which was not affected by chemotherapy, was weakly associated with a poor response and clinical outcome, although this trend was not significant. CONCLUSIONS: In advanced ESCC, expression of MLH1 is reduced during CDDP-based chemotherapy, and this may partly account for poor postoperative survival.  相似文献   
26.
We report two cases of large gastrointestinal stromal tumor (GIST) of the stomach that were successfully treated by hand-assisted laparoscopic surgery (HALS). Two patients, a 56-year-old woman and a 60-year-old man, were admitted to our department for the treatment of a large submucosal tumor of the stomach. After gastrointestinal endoscopy, ultrasonography, computed tomography, and magnetic resonance imaging, we suspected that the masses, measuring 7.0 cm and 8.0 cm in diameter, respectively, were GISTs in the stomach. However, preoperatively, we could not rule out the possibility of malignant neoplasms, because they had been bleeding or gradually growing. Hand-assisted laparoscopic wedge resection was safely performed for the diagnosis and treatment of the submucosal tumor of the stomach. The immunohistochemical diagnosis in both patients was GIST of the stomach with intermediate-grade malignancy. HALS may be a good indication for large GISTs of the stomach that are difficult to diagnose preoperatively, whether they are malignant or benign, because it is safe and minimally invasive, promoting rapid recovery.  相似文献   
27.
Anticarcinoembryonic antigen (CEA) antisera which showed no reactions with normal adult feces were prepared in guinea pigs. Using these, levels of CEA in feces from patients with colorectal carcinoma were measured by gel diffusion and rocket immunoelectrophoresis. Sixteen of 22 (73 percent) patients with carcinoma of the colon or rectum (Dukes' A4/6, B6/8, C6/7, D0/1) had detectable CEA in their feces, while none was detected in the feces of four patients with gastric ulcers or in those of 22 normal volunteers. Five of the 16 fecal CEA-positive patients showed no elevation of plasma CEA levels. Measurements using a commercial CEA kit (Abbott Laboratories) could not detect the differences between fecal CEA values of patients with colorectal carcinoma and benign diseases, or those of normal volunteers. These results suggest that measurement of fecal CEA by specific anti-CEA antisera will be valuable in screening and diagnosis of colorectal carcinoma.  相似文献   
28.
Background: Patients with advanced hepatocellular carcinoma (HCC) need an effective treatment modality because of the poor prognosis of the disease. From an in vitro study, beta-interferon (IFN-beta) has been reported to enhance the antiproliferative effects of doxorubicin on HCC cell lines. In the present study, we investigated the therapeutic effects of combined IFN-beta and doxorubicin intra-arterial injection therapy on patients with advanced HCC. Methods: IFN-beta (3 MIU) and doxorubicin (10 mg/bodyweight) were given by one-shot intra-arterial injection through an arterial port to patients with advanced HCC. One treatment course consisted of three intra-arterial injections per week for 4 weeks. Three courses were conducted and evaluation was done monthly. Results: Eleven patients with advanced HCC were treated with combined IFN-beta and doxorubicin. One patient enteredcomplete remission (CR), seven patients were evaluated as having stable disease (SD) and three as having progressive disease (PD). The mean overall survival was 10 months. The mean survival for CR and SD patients was 15 months, and that for PD patients was 6 months (P = 0.0464, log-rank test). Decrease of serum total bilirubin was observed for all patients. Conclusion: Combined IFN-beta and doxorubicin intra-arterial therapy offers an effective chemotherapy option for patients with advanced HCC by improving liver function and having tolerable side-effects.  相似文献   
29.
A major problem in treating hepatocellular carcinoma (HCC) is intrahepatic recurrence after partial hepatectomy, despite the relatively early detection now possible due to recent developments in non-invasive diagnostic modalities. The present study evaluated the usefulness of preventive therapy for intrahepatic recurrence of HCC. In order to suppress intrahepatic recurrence in HCC patients at high risk of recurrence after tumor removal, we performed preventive transarterial chemotherapy in 23 such patients. Doxorubicin, at a dose of 0.5 mg/kg body weight, was administered, via a catheter inserted at the junction of the common hepatic artery and the gastroduodenal artery, every 2 weeks for the first 2 months, and every month thereafter for at least 1 year. The control group consisted of 30 patients with similar risk of recurrence who underwent partial hepatectomy during the same period without receiving transarterial preventive therapy. The 1-, 2-, 3-, and 5-year cumulative cancer-free survival rates in patients who received transarterial preventive chemotherapy after partial hepatectomy were 87.0%, 47.1%, 21.2%, and 21.2%, respectively, compared to 53.3%, 30.0%, 20.0%, and 13.3%, respectively, in the control group (P<0.05). The 1-, 2-, 3-, and 5-year cumulative overall survival rates were 95.7%, 81.2%, 58.4%, and 48.7%, respectively, in the preventive chemotherapy group, compared to 70.0%, 49.4%, 41.7%, and 19.5%, respectively, in the control group (P<0.05). Thus, the present study demonstrates the limited but significant effect of preventive transarterial chemotherapy for the intrahepatic recurrence of HCC after partial hepatectomy.  相似文献   
30.
AIMS/HYPOTHESIS: This study examined whether locally expressed CTLA4-Ig can suppress the accelerated islet allograft rejection that is induced by donor-specific transfusion. METHODS: CTLA4-Ig-transfected or parental MIN6 cells were transplanted subcutaneously into the right flank of streptozotocin-induced diabetic C3H/Hej mice with or without donor-specific transfusion. For donor-specific transfusion, spleen cells from C57BL/6 mice were injected i.v. at the time of transplantation. In other experiments, CTLA4-Ig-transfected and parental MIN6 cells were transplanted separately into each flank, together with donor-specific transfusion. Rejection was defined as a blood glucose concentration of more than 300 mg/dl in two consecutive measurements, and graft survival was confirmed by hyperglycaemia after the grafts were removed. The effect of an anti-CTLA4 antibody on the survival of CTLA4-Ig-transfected MIN6 cells was also examined. RESULTS: In 7 of 12 donor-specific transfusion sensitised mice, CTLA4-Ig-transfected MIN6 cells remained viable 20 days after grafting, whereas all parental MIN6 cells ( n = 10) were rejected promptly, within 14 days. The prolonged allograft survival was observed even in the absence of detectable levels of serum CTLA4-Ig, while the surviving allografts continued to produce CTLA4-Ig in situ. This protection was abrogated by an anti-CTLA4 antibody, but not by a control antibody. Furthermore, six animals that maintained normoglycaemia after the separate transplantation of parental and CTLA4-Ig-transfected MIN6 cells into each flank all showed abrupt hyperglycaemia after the CTLA4-Ig/MIN6 graft was removed, suggesting that this protection operated locally. CONCLUSION/INTERPRETATION: A beta-cell line genetically engineered to secrete CTLA4-Ig can protect a graft locally from the alloimmune response induced by donor-specific transfusion.  相似文献   
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