40 EARLY DEVELOPMENT OF RECONSTRUCTED MOUSE EMBRYOS USING BONE MARROW CELLS FROZEN WITHOUT CRYOPROTECTANT

Animal cells frozen with suitable cryoprotectants have been successfully cryopreserved for long periods of time, maintaining viability upon thawing. Animal cells frozen without cryoprotectant, however, may suffer serious damage and not be useful as donors in somatic cell nuclear transfer (SCNT). However, in some cases, old animal samples were frozen only as a whole body or a piece of tissue without cryoprotectant. If the cells from such old samples could be useful for SCNT, then there are potentially many candidates where individual animals could be reproduced. In this study, we examined the possibility of using mouse bone marrow cells frozen without cryoprotectant as nuclear donors in SCNT. Thigh bones were collected from B6C3F1 mice and frozen in either a –25�C or a –80�C freezer for more than one month. Thawing of frozen bones was performed by placing them in an incubator at 37�C. Bone marrow cells were collected by washing the bone cavity with saline. Recipient oocytes for SCNT were collected from B6D2F1 female mice. The enucleation of recipient oocytes and the injection of nuclei were performed as previously reported (Wakayama et al. 1998 Nature 394, 369–374) with a piezo-actuated micromanipulator system. In this study, 4 groups of mouse cells (fresh bone marrow cells, bone marrow cells frozen at –25�C, bone marrow cells frozen at –80�C, and fresh cumulus cells) were used as the nuclear donors in SCNT. After nuclear injection, embryos were kept in mCZB medium for 1 h at 37�C. Subsequently, embryos were cultured for 3 h with 5 µg mL–1 cytochalasin B and 10 mm SrCl2 for activation and cultured for an additional 20 h in mKSOM medium. The nuclear dynamics of SCNT embryos in each donor cell group was observed using 42,6-diamidino-2-phenylindole (DAPI) staining and a fluorescent microscope at 0, 1, 7, and 24 h after nuclear injection. Data were analyzed by Student's t-test. The cell viability after thawing by trypan blue vital staining was about 20% regardless of freezing temperature. At 7 h after nuclear injection, the SCNT embryos injected with frozen bone marrow cells, regardless of freezing temperature, had more single pronuclei (67%, 54/81; P < 0.05) than SCNT embryos injected with either fresh bone marrow cells (36%, 26/73) or cumulus cells (28%, 67/236). At 24 h after nuclear injection, fewer SCNT embryos injected with bone marrow cells, either fresh or frozen, developed to the 2-cell stage (fresh: 11%, 6/56; frozen at –25�C: 21%, 5/24; frozen at –80�C: 20%, 10/49) than SCNT embryos injected with cumulus cells (58%, 185/319; P < 0.05). There was no difference in the embryonic development to the 2-cell stage among SCNT embryos injected with either fresh or frozen bone marrow cells. Further studies are required to determine whether cells frozen without cryoprotectant are capable of resulting in viable clones.

Transforming growth factor-beta(2) polymorphisms are associated with childhood atopic asthma

BACKGROUND

Transforming growth factor (TGF)-beta plays an important role in the regulation of airway inflammation and remodelling in asthma. Recent studies suggest that TGF-beta(2) is a predominant isoform expressed in severe asthma and it is also associated with airway remodelling.

OBJECTIVE

To determine whether the polymorphisms in TGF-beta(2) are associated with childhood atopic bronchial asthma in a Japanese population.

METHODS

We identified a total of eight polymorphisms and characterized the linkage disequilibrium (LD) mapping of the gene. Three variants in the promoter and 3'UTR were genotyped, and we conducted an association study of TGF-beta(2) (childhood atopic asthma n=297, normal controls n=555). An association analysis of these variants and an expression and functional analysis were performed.

RESULTS

3'UTR 94862T >A was found to be significantly associated with the risk of childhood atopic asthma (P=0.00041). The -109-->ACAA ins promoter variant was also associated with the risk of childhood atopic asthma (P=0.0037). TGF-beta(2) expression was observed in both the normal and asthmatic bronchial epithelium, and both real-time PCR and an ELISA showed a significant basal and TGF-beta(1)-induced TGF-beta(2) expression in the bronchial epithelial cell line BEAS2B. Furthermore, the promoter variant -109-->ACAA ins increased the TGF-beta(2) promoter-reporter activity in BEAS2B cells.

CONCLUSIONS

Our data suggest that TGF-beta(2) may therefore be involved in the development of childhood atopic asthma by means of functional genetic polymorphism. The polymorphisms in TGF-beta(2) may become important information for asthma susceptibility in children.

Hypermethylation of multiple genes as clonal markers in multicentric hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is highly malignant and prone to multicentric occurrence. Differentiation between a true relapse of HCC and a second primary tumour appearing is of clinical importance. At this point, no convenient method is available to determine the origin of these HCCs. Tissue samples were obtained from 19 patients and analysed for the promoter hypermethylation status of multiple tumour suppressor genes (p16, DAP-Kinase, MGMT, GSTP1, APC, RIZ1, SFRP1, SFRP2, SFRP5, RUNX3, and SOCS1) using methylation-specific PCR (MSP). Methylation status was used to determine tumour clonality. In each of the 19 cases, at least one tumour was recognised as having an aberrantly methylated gene. The frequency of the methylation in tumour tissue was 57.1% in p16, 2.4% in DAP-kinase, 23.8% in GSTP1, 90.5% in APC, 45.2% in RIZ1, 64.3% in SFRP1, 59.5% in SFRP2, 28.6% in SFRP5, 47.6% in RUNX3, and 54.8% in SOCS1, while in MGMT, no aberrant methylation was detected. The methylation status of these genes was assessed using MSP as being either positive or negative, and was used to determine the tumour clonality. The clonality of every tumour could be decided even with lesions that could not be judged by clinical diagnosis or by another molecular method (mt DNA mutation). Determining the methylation status of multiple genes in multicentric HCC was useful as a clonal marker and provided useful information for characterising the tumour. From our findings, multicentric HCCs tend to occur more independently than metastatically from the original tumour. Expanded study should be pursued further for a better understanding of the molecular mechanism of hepatocarcinogenesis.

Carbon monoxide protects rat lung transplants from ischemia-reperfusion injury via a mechanism involving p38 MAPK pathway

Carbon monoxide (CO) provides protection against oxidative stress via anti-inflammatory and cytoprotective actions. In this study, we tested the hypothesis that a low concentration of exogenous (inhaled) CO would protect transplanted lung grafts from cold ischemia-reperfusion injury via a mechanism involving the mitogen-activated protein kinase (MAPK) signaling pathway. Lewis rats underwent orthotopic syngeneic or allogeneic left lung transplantation with 6 h of cold static preservation. Exposure of donors and recipients (1 h before and then continuously post-transplant) to 250 ppm CO resulted in significant improvement in gas exchange, reduced leukocyte sequestration, preservation of parenchymal and endothelial cell ultrastructure and reduced inflammation compared to animals exposed to air. The beneficial effects of CO were associated with p38 MAPK phosphorylation and were significantly prevented by treatment with a p38 MAPK inhibitor, suggesting that CO's efficacy is at least partially mediated by activation of p38 MAPK. Furthermore, CO markedly suppressed inflammatory events in the contralateral naïve lung. This study demonstrates that perioperative exposure of donors and recipients to CO at a low concentration can impart potent anti-inflammatory and cytoprotective effects in a clinically relevant model of lung transplantation and support further evaluation for potential clinical use.

A phase II study to establish a referential arm for treatment of gastric cancer patients with intraperitoneal micrometastases

15002

Background: Gastric cancer patients with free cancer cells in the peritoneal cavity as detected by cytologic examination of the peritoneal washes (CY1) are known to have dismal prognosis. In vivo studies by the authors suggest prognostic impact of early postoperative treatment with S-1 (Nakanishi H, et al. Cancer Sci 2003;94:112–8) . No standard treatment for this population has been proposed to date. Methods: A phase II study was conducted to evaluate the efficacy of S-1, a new oral fluoropyrimidine, given postoperatively to patients with CY1 disease. Eligibility criteria included histologically confirmed adenocarcinoma of the stomach without distant metastasis (peritoneal seeding allowed if completely resected), curatively resected with negative margins, <80 years of age with adequate organ functions and preoperative PS of 0∼2, and written informed consent. The primary endpoint was 2-year survival rate and secondary endpoints were time to treatment failure and safety. By referring to the historical control (2-year survival rate: 13.3%, 90% CI 3.1∼23.5%), the target 2- year survival rate was set at 36 % with estimated 90% CI>23.5%, and the sample size was calculated as 50. Results: Forty eight patients were accrued before the study was closed, and one patients was found to be ineligible (negative for the cytologic examination). Of 47 patients, 32 were men. Median age was 66 years (range: 39∼79 years). Serosal invasion was confirmed in 44 patients (94%) and node metastasis in 42 (89%). Seven patients had macroscopic but resectable peritoneal deposits. D2 dissection was encouraged and performed in 33 patients (70%). To date, median survival time was 21.7 months with 2-year survival rate of 43.5%. One patient died of ischemic heart disease 5 days after the initiation of treatment, and treatment for 7 other patients was discontinued due to toxicity. Time to treatment failure was 9.8 months and progression-free survival was 12.9 months. The most frequent >G3 toxicity was neutropenia (n=6), followed by anorexia/nausea (n=4). Conclusions: Although further period of observation is required, postoperative S-1 is likely to overwhelm the survival data obtained in the pre-S-1 era. Toxicity was manageable and 80% of the patients tolerated the treatment.

No significant financial relationships to disclose.

Enhanced efficacy of herpes simplex virus mutant HF10 combined with paclitaxel in peritoneal cancer dissemination models

BACKGROUND/AIMS

Oncolytic viral therapy is used worldwide. Many genetically engineered viruses have been evaluated for their potential as a new therapeutic agent for cancer. HF10, herpes simplex virus (HSV) type-1 clone, has remarkable anti-tumor effects, based on our previous research. In this study, we investigated the ability of HF10 to infect and lyse murine colon cancer cells, CT26, in vitro, and tested its efficacy in an immuno-competent animal model of colorectal cancer. Further, we attempted to evaluate HF10/paclitaxel combination therapy.

METHODOLOGY

In vitro, viral replication and cytotoxicity of HF10 against CT26 was observed. In vivo, BALB/c mice harboring carcinomatous peritonitis of CT26 cells were treated with HF10, paclitaxel or HF10 combined with paclitaxel.

RESULTS

HF10 is effective for peritoneal dissemination without ascites. The combination of HF10 and paclitaxel prolonged survival of mice bearing carcinomatous dissemination of CT26 compared with the controls, HF10 alone and paclitaxel alone. Paclitaxel did not suppress viral replication and cytotoxicity of HF10.

CONCLUSIONS

These results indicate that the combination of HF10 and paclitaxel had a remarkable effect as a cancer therapy and this method is applicable to almost all advanced cancers. This new combination therapy is a potentially epoch-making cancer therapy.

Suitability of a US3-inactivated HSV mutant (L1BR1) as an oncolytic virus for pancreatic cancer therapy

Recently, the use of oncolytic viruses against cancer has attracted considerable attention. We studied the potential of the US3 locus-deficient herpes simplex virus (HSV), L1BR1, for oncolytic virus therapy. Its high specificity and potency indicate that L1BR1 is a promising candidate as a new oncolytic virus against pancreatic cancer. Moreover, the virus exhibited the unique characteristic of increasing apoptosis when used in combination with anticancer drugs. We assessed the feasibility of using the US3 locus-deficient HSV named L1BR1 as a new replication-competent oncolytic virus for the treatment of pancreatic cancer. The US3 locus of HSV has been shown to be a key gene in producing a multifunctional protein kinase that inhibits apoptosis induced by viral infections, chemicals and ultraviolet (UV) light. L1BR1 has been reported to be more than 10 000-fold less virulent than the parental virus in mice. In this study, we examined the tumor specificity and oncolytic effect of this attenuated replication-competent virus, L1BR1, in pancreatic cancers derived from SW1990, Capan2 and Bxpc-3cells compared with the parent virus and other well-known oncolytic herpes viruses (R3616 and hrR3). We also studied the efficacy of L1BR1 for the induction of apoptosis as an attribute of this virus in combination with the anticancer drugs 5FU and cisplatin. The combined treatment of the pancreatic cancer cells with L1BR1 and these anticancer drugs enhanced apoptosis significantly. More importantly, L1BR1 showed the lowest replication capacity in normal human hepatocytes, but the highest tumor-reducing effect in vivo among the oncolytic herpes viruses tested. In addition, L1BR1 significantly increased the induction of apoptosis of cancer cells when treated in combination with anticancer drugs although the parental virus inhibited the induction of apoptosis. These results suggest that L1BR1 is promising as a new anticancer oncolytic virus.

Oncolytic virus therapy--foreword

We are very pleased and proud to be able to publish this special issue of Current Cancer Drug Targets devoted to oncolytic virus therapy covering basic and clinical research on adenovirus, vaccinia virus, herpes virus, and Newcastle disease virus. In these papers, we welcome the world's top authorities in the field who have generously contributed their latest review articles for exclusive publication in this special issue. Moreover, this issue also includes a range of opinion from government drug organizations. Here we simply wish to bring together the newest knowledge and experience in the field of cutting-edge oncolytic virus therapy for researchers and every kind of cancer therapist. The Foreword presents a historical perspective on the development of oncolytic virus together with the encouraging results of recent clinical trials (e.g., H101 has been tested in clinical trial of nearly 250 patients and approved for human use by the Chinese FDA, while PV701 has been tried in over 110 patients, as described in our special issue).

Clinical Experiment of Mutant Herpes Simplex Virus HF10 Therapy for Cancer

We reviewed our clinical trial using mutant herpes simplex virus "HF10". We have evaluated the safety and effect of HF10 against recurrent breast cancer since 2003 and also applied HF10 to non-resectable pancreatic cancer since 2005. An oncolytic herpes simplex virus type 1, mutant HF10, has been isolated and evaluated for anti-tumor efficacy in syngeneic immunocompetent mouse models. From long time before clinical trial, we have found that the mutant virus can have remarkable potential to effectively treat cancer in experimental studies using animals, and that all of the surviving mice acquire resistance to rechallenge of the tumor cells. A number of studies have shown that HF10 is effective and safe for use in localized or peritoneally disseminated malignant tumors of non-neuronal origin in animals. Pilot studies using HF10 have been initiated in patients with metastatic breast cancer. For each patient, 0.5 ml HF10 diluents at various doses were injected into test nodule, and 0.5 ml sterile saline was injected into a second nodule. All patients were monitored for local and systemic adverse effects, and the nodules were excised 14 days after viral injection for histopathological studies. All patients tolerated the clinical trial well. While no adverse effects occurred, there was cancer cell death and 30-100% regression histopathologically in recurrent breast cancer. As mentioned above, intratumoral injection of mutant herpes simplex virus HF10 for recurrent metastatic breast cancer was safe and effective. Also a trial for non-resectable pancreatic cancer being carried out on the basis of the above result has proved to be innocuous and has been in progress to assess the clinical benefit and enhance the potentiality of HF10 against cancer.

Normal Hepatic Hemodynamics During Early Postoperative Period in Recipients With Adult Live Donor Liver Transplantation

To recognize "normal" hepatic hemodynamics after live donor liver transplantation (LDLT), we analyzed Doppler parameters on recipients with a right liver graft and donors after extended left hepatectomy. Theoretically these values should be the same. From April 2000 to October 2004, 20 LDLTs were performed using a right liver graft. The 10 recipients without postoperative complications and their donors were included in this study. Portal venous velocity (PVV; cm/s), hepatic arterial peak systolic velocity (cm/s), and hepatic venous peak velocity (HVPV; cm/s) were measured during the first 2 weeks. In donors PVV and HVPV after LDLT were significantly higher after than before left hepatectomy: 19.2 +/- 4.2 vs. 31.5 +/- 13.0 cm/s (P = .013) and 23.0 +/- 7.2 vs. 41.8 +/- 10.3 cm/s respectively (P = .010). However, there were mild degrees of increased PVV and HVPV. In recipients, a markedly increased PVV (106.3 +/- 45.2 cm/s on day 1) was significantly higher than that in donors on each postoperative day. The hepatic arterial resistive index in recipients was also significantly higher than that in donors on each postoperative day, for example, 0.72 +/- 0.11 vs 0.62 +/- 0.04 on day 1 (P = .0326). In conclusion, we have shown "abnormal" hepatic hemodynamics in even those recipients without complications during the early postoperative period after LDLT.

Molecular basis for sensitivity and acquired resistance to gefitinib in HER2-overexpressing human gastric cancer cell lines derived from liver metastasis

Gastric cancer metastasised to the liver was found to overexpress HER2 at a significantly higher incidence than primary gastric cancers. The purpose of the present study was to investigate the possibility of molecular therapy targeting HER2 overexpression in gastric cancer liver metastasis. We developed three new HER2-overexpressing gastric cancer cell lines (GLM-1, GLM-2, GLM-4) without epidermal growth factor receptor (EGFR) mutations derived from such liver metastasis, two of which had HER2 gene amplifications. All these GLM series of cell lines were highly sensitive to gefitinib in vitro, a specific inhibitor of EGFR tyrosine kinase (Iressa) rather than anti-HER2 antibody trastuzumab (Herceptin), whereas most of the HER2 low-expressing counterparts were not. In these HER2-overexpressing GLM series, protein kinase B (Akt), but not extracellular signal-regulated kinase 1/2 (ERK1/2), was constitutively phosphorylated, and gefitinib efficiently inhibited this Akt phosphorylation, induced strong apoptosis in vitro and exhibited antitumour activity in tumour xenografts in nude mice. This gefitinib-mediated antitumour effect in xenograft was significantly potentiated by trastuzumab treatment. On the other hand, gefitinib-resistant cells (GLM-1R) exhibited increased EGFR expression, followed by constitutive activation of mitogen-activated protein kinase (MAPK) pathway. These results suggest that the antitumour effect of gefitinib is due to the effective inhibition of HER2-driven constitutive activation of phosphatidylinositol-3-kinase (PI3K)/Akt pathway, and that the acquired resistance to gefitinib is due to the constitutive activation of Ras/MAPK pathway in compensation for PI3K/Akt pathway. Gastric cancer liver metastasis with HER2 overexpression would be a potential molecular target for gefitinib and trastuzumab.

PAI-1 expression levels in esophageal and colorectal cancers are closely correlated to those in corresponding normal tissues

To investigate the mechanism of PAI-1 overexpression in esophageal and colorectal cancers, PAI-1 expression levels in these cancers were compared to those in corresponding normal tissues. Quantitative RT-PCR was performed for the PAI-1 gene in esophageal and colorectal cancer tissues and in the corresponding normal tissues and the association between PAI-1 expression levels in these tissues was evaluated. There was a significant correlation between esophageal and colorectal cancer and the corresponding normal PAI-1 expressions with a Spearman's rank correlation coefficient of 0.77 (p < 0.0001) and 0.81 (p < 0.0001), respectively. In previous studies, PAI-1 overexpression was found to be significantly associated with the malignancy of esophageal and colorectal cancers. Taken together, PAI-1 overexpression in esophageal and colorectal cancers might originate from higher PAI-1 expression in corresponding normal tissues and result in a malignant phenotype of these cancers.

Ex vivo application of carbon monoxide in University of Wisconsin solution to prevent intestinal cold ischemia/reperfusion injury

Carbon monoxide (CO), a byproduct of heme catalysis, was shown to have potent cytoprotective and anti-inflammatory effects. In vivo recipient CO inhalation at low concentrations prevented ischemia/reperfusion (I/R) injury associated with small intestinal transplantation (SITx). This study examined whether ex vivo delivery of CO in University of Wisconsin (UW) solution could ameliorate intestinal I/R injury. Orthotopic syngenic SITx was performed in Lewis rats after 6 h cold preservation in control UW or UW that was bubbled with CO gas (0.1-5%) (CO-UW). Recipient survival with intestinal grafts preserved in 5%, but not 0.1%, CO-UW improved to 86.7% (13/15) from 53% (9/17) with control UW. At 3 h after SITx, grafts stored in 5% CO-UW showed improved intestinal barrier function, less mucosal denudation and reduced inflammatory mediator upregulation compared to those in control UW. Preservation in CO-UW associated with reduced vascular resistance (end preservation), increased graft cyclic guanosine monophosphate levels (1 h), and improved graft blood flow (1 h). Protective effects of CO-UW were reversed by ODQ, an inhibitor of soluble guanylyl cyclase. In vitro culture experiment also showed better preservation of vascular endothelial cells with CO-UW. The study suggests that ex vivo CO delivery into UW solution would be a simple and innovative therapeutic strategy to prevent transplant-induced I/R injury.

PAI-1 (Plasminogen activator inhibitor-1) expression levels in colorectal cancers and corresponding normal tissues

10094

Background: We performed a quantitative RT-PCR for Plasminogen Activator Inhibitor-1 (PAI-1) gene in 55 surgical specimens of colorectal cancer (CRC) and corresponding normal mucosa. To test the hypothesis that PAI-1 may serve as a candidate marker for the malignant potential of CRC, we evaluated the possible relationship between PAI-1 gene expression levels and clinicopathological findings in CRC. Next, to investigate the mechanism of PAI-1 overexpression in CRC, we compared the PAI-1 expression levels in these cancers with those in the corresponding normal tissues. Results: A significant increase in PAI-1 expression scores was observed in node-positive CRCs (2.19Å}0.43) compared to negative ones (0.35Å}0.42) (P=0.0037) as well as in CRCs with distant metastasis (3.50Å}1.18) compared to negative ones (0.99Å}0.30). A significant increase in PAI-1 expression scores was observed in lymph node metastasis-positive CRCs (2.19Å}0.43) compared to negative ones (0.35Å}0.42) (P=0.0037) as well as in distant metastasis-positive CRCs (3.50Å}1.18) compared to negative ones (0.99Å}0.30). The PAI-1 expression score markedly increased with the tumor stage (P=0.0063; ANOVA test). Moreover, multivariate analysis revealed the PAI-1 expression score to be a strong and independent prognostic factor for CRC (P=0.0432). There was a significant correlation between CRC and corresponding normal PAI-1 expressions with a Spearman’s rank correlation coefficient of 0.81 (P < 0.0001). Conclusion: These results suggested that PAI-1 might serve as a new parameter for the prediction of prognoses in CRC. Taken together, PAI-1 overexpression in CRCs might originate from higher PAI-1 expression in the corresponding normal tissues and result in a malignant phenotype of these cancers.

No significant financial relationships to disclose.

Phase II study of weekly paclitaxel as a second line chemotherapy for metastatic/recurrent gastric carcinoma

14059

Background: There is currently no standard treatment for gastric carcinoma patients (pts) who failed initial chemotherapy. Since performance status of these pts deteriorates rapidly, moderate and dose-fractionated single agent regimens have been preferred in Japan in the second line setting. Weekly paclitaxel, one of commonly used regimens in this setting, was explored for the first time in a formal phase II study. Methods: Pts with histologically confirmed gastric carcinoma who had unresectable or recurrent disease with ≥1 measurable lesions per RECIST were eligible. Other eligibility criteria included confirmed progressive disease (PD) per RECIST during a front line chemotherapy, PS ≤2, adequate liver, kidney, and marrow functions, no active gastrointestinal bleeding, and written informed consent. Patients received 80 mg/m2 of paclitaxel weekly for 3 successive weeks with one week of rest. The cycle was repeated until objective disease progression or drug intolerance. Results: 35 pts were enrolled: 29 men and 6 women, age 62 (48∼74), 6 unresectable and 29 recurrent cancers, 13 with poorly differentiated phenotype and 20 with differentiated type, 22 PS0, 8 PS1, and 6 PS2. All front line treatments involved oral fluoropyrimidines and had been S-1 in 29, S-1/CDDP in 5, S-1/CPT-11 in one, and UFT in one patient. One pt declined to continue the treatment due to a Grade 2 taste disturbance after a single dose of paclitaxel, and 34 other pts were evaluable for response. Partial response was observed in 6 pts (response rate 17.6%). Median time to progression was 97 days and median survival time was 214 days (467 days among 22 PS0 patients). The incidence of ≥Grade 3 adverse events were as follows: neutropenia in 7 pts, leucopenia in 5, anemia in 4, anorexia in 4, neurological disorder, nausea, diarrhea, asthenia, and dyspnea in one. Conclusions: Activity of weekly paclitaxel was modest for pts with fluoropyrimidine-refractory gastric carcinoma, but median survival time was satisfactory, with a mild toxicity profile. Further phase II study under less strict eligibility criteria (e.g. inclusion of patients with elevated tumor markers or subjective evidence of clinical deterioration during the front line therapy as the sole indication of disease progression) is underway.

No significant financial relationships to disclose.

Adjuvant chemotherapy with tegafur/uracil (UFT) for gastric cancer. A meta-analysis of centrally randomized clinical trials

4033

Background: A consensus regarding standard adjuvant chemotherapy for curatively resected gastric cancer has not been obtained between Japan and Western world. In order to evaluate the effect of UFT which is the most frequently used in Japan over surgery alone control, a meta-analysis was performed investigating 4 clinical trials. Methods: After meticulous examination of each trial, trials with improper randomization using envelop method were excluded from the analysis. A total of 1503 patients, enrolled in four relevant trials (JCOG 8401, JCOG 8801, JCOG9206–2, and NSAS-GC) using UFT for chemotherapy and performed by central randomization, were determined eligible for the meta-analysis. The endpoint was overall survival and intent-to treat analysis was implemented. Results: The 5-year overall survival odds ratio was 0.70 (95%CI; 0.54–0.89). The treatment effect of oral UFT was shown to be statistically significant (p=0.01) over surgery alone therapy (n=1251). No significant heterogeneity between the trials was demonstrated (p=0.365). The 5-year overall survival odds ratio was 0.71(95%CI; 0.54–0.92). Conclusions: From these results of the present meta-analysis, it is strongly suggested that chemotherapy after surgery with UFT, can improve survival of the patients with curatively resected gastric cancer, and UFT should be considered as the standard postoperative adjuvant treatment for gastric cancer in Japan, where extensive gastrectomy with D2 lymph node dissection is implemented as a routine surgical procedure.

No significant financial relationships to disclose.

Correlation between copy number of mitochondrial DNA and clinico-pathologic parameters of hepatocellular carcinoma

AIMS

In the current study, we investigated possible correlations of the mtDNA copy number in hepatocellular carcinoma (HCC) with the pathological findings and prognosis.

METHODS

We studied 31 HCC specimens using quantitative real-time polymerase chain reaction analysis, and the correlation between the mtDNA copy number and the clinicopathologic parameters and mutations in the D-loop region of the mitochondrial genome.

RESULTS

The mtDNA copy number was reduced in HCCs compared with the corresponding non-cancerous liver tissues (p=0.002), and significantly correlated with tumour size (p=0.014) and cirrhosis (p=0.048). Patients with a low mtDNA copy number tended to show shorter 5-year survival rates than patients with a high mtDNA copy number when assessed by Kaplan-Meier curves, but not a significant (overall survival rate, 63 vs 83%; p=0.19). The copy number of HCC with mtDNA D-loop mutation or deletion was lower, but not significantly so (p=0.656, p=0.590, respectively).

CONCLUSIONS

Our results indicated that a reduced copy number of mtDNA is correlated with HCC and associated with malignant potential.

Plasminogen activator inhibitor-1 as a potential marker for the malignancy of colorectal cancer

To test the hypothesis that plasminogen activator inhibitor-1 (PAI-1) may serve as a candidate marker for the malignancy of colorectal cancer (CRC), we performed a quantitative RT–PCR for PAI-1 gene and evaluated the possible relationship between PAI-1 gene expression levels and clinicopathological findings in CRC. A significant increase in PAI-1 expression scores was observed in lymph node metastasis-positive CRCs (2.19±0.43) compared to negative ones (0.35±0.42) (P=0.0037) as well as in distant metastasis-positive CRCs (3.50±1.18) compared to negative ones (0.99±0.30). The PAI-1 expression score markedly increased with the tumour stage (P=0.0063; ANOVA test). Moreover, multivariate analysis revealed the PAI-1 expression score to be a strong and independent prognostic factor for CRC (P=0.0432). These results suggested that PAI-1 might serve as a new parameter for the prediction of prognoses in CRC.

CDK5 regulates cell-cell and cell-matrix adhesion in human keratinocytes

BACKGROUND

CDK5 is a member of proline-directed serine/threonine kinases. Although its cDNA was originally cloned as a homologue to those for the other members of the cyclin-dependent kinase (CDK) family, CDK5 has been shown to function differently from other CDKs. CDK5 is activated by non-cyclin partners, p35 and p39, and important during brain development by influencing adhesion, migration and differentiation of neurones.

OBJECTIVES

We sought to investigate the expression and functions of CDK5 in human keratinocytes.

METHODS

Expression of CDK5/p35, interaction of CDK5/p35 with adhesion molecules, and its roles in cell-cell and cell-matrix adhesion were studied by reverse transcriptase-polymerase chain reaction, immunoblotting and aggregation/adhesion assays in primary cultured normal human keratinocytes from infant foreskins and a human keratinocyte HaCaT cell line. Localization of CDK5 and p35 in normal human epidermis and psoriatic epidermis was studied by immunohistochemistry.

RESULTS

Both CDK5 and p35 were expressed in primary cultured keratinocytes, HaCaT cells and normal human epidermis. Roscovitine, an inhibitor of CDK5, enhanced Ca2+-dependent (cadherin-dependent) aggregation of HaCaT cells whereas it inhibited adhesion of HaCaT cells to fibronectin associated with reduced active states of beta1 integrin. Interestingly, psoriatic skin showed reduced CDK5 and p35 expression in the lower half of the epidermis, which might be associated with decreased amount of activated beta1 integrin in the epidermis of psoriatic skin.

CONCLUSIONS

CDK5/p35 may be involved in cell-cell and cell-matrix adhesion in human keratinocytes by differently regulating cadherins and integrins. Furthermore, reduced expression of CDK5/p35 in the epidermis might be involved in the pathogenesis of psoriasis.

Sequential blood level monitoring of basiliximab during multisession plasmapheresis in a kidney transplant recipient

Basiliximab, a chimeric monoclonal antibody against the alpha chain of the interleukin-2 receptor (IL-2R) has been used in renal transplant patients. We monitored sequential blood concentrations of basiliximab in a patient who received a kidney transplant with basiliximab-based immunosuppression together with multiple sessions of plasmapheresis. A 34-year-old man received a living-related kidney transplant with induction immunosuppression including tacrolimus, mycophenolate, methylprednisolone, and basiliximab. Severe antibody-mediated acute rejection lead to a requirement for hemodialysis. Deoxyspergualin was administered for 10 days at a daily dose of 5 mg/kg combined with eight sessions of double filtration plasmapheresis (DFPP). After treatment, the serum creatinine returned to 0.95 mg/dL, and there were no major complications or infections. Sequential basiliximab blood levels of the patient were monitored following transplantation. The serum basiliximab concentration decreased by 72.4% after five consecutive DFPPs, and by 87.6% after eight DFPP sessions. The elimination rate of basiliximab (DeltaBLX) was 6.1% before DFPP, but increased over eight DFPPs to 20.5%. Serum basiliximab concentrations declined to 0.16 microg/mL on day 33, which is below the IL-2R saturation concentration (0.2 microg/mL). Multiple sessions of plasmapheresis using DFPP enhanced the elimination of serum basiliximab at an average elimination rate of 19.1%. In the patient reported on here, the serum basiliximab concentration fell to below the IL-2R saturation level (0.2 microg/mL) within 1 month of living-related kidney transplantation. We recommend that additional basiliximab infusions be considered for cases undergoing more than three plasmapheresis sessions.