Efficacy of novel hypoxic cell sensitiser doranidazole in the treatment of locally advanced pancreatic cancer: long-term results of a placebo-controlled randomised study.

Novel hypoxic cell radiosensitiser doranidazole was tested for unresectable pancreatic cancer administered at intraoperative radiotherapy. Short-term survival was not different. However, difference has been observed concerning 3-year survival (doranidazole group vs. placebo; 23% vs. 0%, p=0.0192). This sensitiser might be effective in improving long-term survival for pancreatic cancer.

[Pancreatic groove carcinoma in a young adult].

A 26-year-old woman was admitted to our hospital with jaundice. Under a diagnosis of biliary and duodenal stenosis due to so called "groove pancreatitis", prednisolone (30 mg/day, 2 weeks) was administered. But these stenosis did not improve after the treatment, and pancreaticoduodenectomy was performed. Histologically, poorly differentiated adenocarcinoma was found in the "groove" between the duodenum and the pancreatic head. We should be kept of "pancreatic groove carcinoma" in mind when making a diagnosis of "groove pancreatitis".

A novel cancer testis antigen that is frequently expressed in pancreatic, lung, and endometrial cancers.

PURPOSE: To isolate cancer testis antigens that are expressed in pancreatic cancers and may be useful in clinical applications. EXPERIMENTAL DESIGN: To efficiently isolate cancer testis antigens, a testis cDNA library was immunoscreened (SEREX) with serum from a patient with pancreatic ductal adenocarcinoma. The expression of isolated antigens in various cancer cell lines and tissues was evaluated by reverse transcription-PCR and Northern blot analyses. The immunogenicity of the antigen in cancer patients was evaluated by detection of the IgG antibody in sera from patients with various cancers. RESULTS: Of the three clones isolated through screening of a total of 2 x 10(6) cDNA library clones, one clone (KU-CT-1) was found to be expressed in various cancers but only in testis among normal tissues, indicating that it was a novel cancer testis antigen. The KU-CT-1 gene is located on chromosome 10p12 and produces two splice variants, which encode proteins of 397 and 872 amino acids, respectively. KU-CT-1 was expressed in pancreatic cancer tissues (3 of 9, 33%), lung cancer tissues (9 of 24, 38%), and endometrial cancer tissues (7 of 11, 64%). Specific serum IgG antibodies were detected in 3 of 20 pancreatic cancer patients, 2 of 12 endometrial cancer patients, 1 of 18 colon cancer patients, and 1 of 10 prostate cancer patients but not detected in 30 healthy individuals. CONCLUSIONS: KU-CT-1 is a new cancer testis antigen that is expressed in pancreatic, lung, and endometrial cancers and may be useful for diagnosis and immunotherapy for patients with various cancers.

Intrinsic chemoresistance to gemcitabine is associated with decreased expression of BNIP3 in pancreatic cancer.

PURPOSE: Although chemotherapy with gemcitabine is a common mode of treatment of pancreatic cancer, 75% of patients do not benefit from this therapy. It is likely that the sensitivity of cancer cells to gemcitabine is determined by a number of different factors. EXPERIMENTAL DESIGN: To identify genes that might contribute to resistance to gemcitabine, 15 pancreatic cancer cell lines were subjected to gemcitabine treatment. Simultaneously, gene expression profiling using a cDNA microarray to identify genes responsible for gemcitabine sensitivity was performed. RESULTS: The pancreatic cancer cell lines could be classified into three groups: a gemcitabine "sensitive," an "intermediate sensitive," and a "resistant" group. Microarray analysis identified 71 genes that show differential expression between gemcitabine-sensitive and -resistant cell lines including 27 genes relatively overexpressed in sensitive cell lines whereas 44 genes are relatively overexpressed in resistant cell lines. Among these genes, 7 genes are potentially involved in the phosphatidylinositol 3-kinase/Akt pathway. In addition to this major signaling pathway, Bcl2/adenovirus E1B 19 kDa protein interacting protein (BNIP3), a Bcl-2 family proapoptotic protein, was identified as being expressed at lower levels in drug-resistant pancreatic cancer cell lines. In an analysis of 21 pancreatic cancer tissue specimens, more than 90% showed down-regulated expression of BNIP3. When expression of BNIP3 was suppressed using small interfering RNA, gemcitabine-induced cytotoxicity in vitro was much reduced. CONCLUSIONS: These results suggest that BNIP3 and the phosphatidylinositol 3-kinase/Akt pathway may play an important role in the poor response to gemcitabine treatment in pancreatic cancer patients.

Restoration of SMAD4 by gene therapy reverses the invasive phenotype in pancreatic adenocarcinoma cells.

SMAD4 is a critical cofactor in signal transduction pathways activated in response to transforming growth factor-beta (TGF-beta)-related ligands, regulating cell growth and differentiation. The roles played by SMAD4 inactivation in tumours highlighted it as a tumour-suppressor gene. However, restoration of the TGF-beta antiproliferative pathway following SMAD4 gene transfer in null-tumour cell lines is controversial. Herein, we report the inhibitory effects of SMAD4 on pancreatic tumour invasion and angiogenesis. Adenoviral transfer of this gene in a panel of SMAD4 homozygous-deleted human pancreatic tumour cell lines restored SMAD4 protein expression and function. Although it did not affect proliferation significantly in vitro, SMAD4 inhibited in vivo tumour growth in immunodeficient mice. In this xenograft setting, differential suppression of tumour growth in vivo was mediated, at least in part, through downregulation of vascular endothelial growth factor and expression of gelatinases. We documented the reduced invasion and angiogenesis histologically and by intravital microscopy, and gained mechanistic insight at the messenger and protein level. Finally, we found a negative reciprocal regulation between SMAD4 and ETS-1. ETS-1 is considered a marker for tumour invasion. Upon SMAD4 deletion, we detected high expression levels of ETS-1 in pancreatic tumour cells, suggesting the shift of the pancreatic tumour toward an invasive phenotype.

Inserting chromosome 18 into pancreatic cancer cells switches them to a dormant metastatic phenotype.

We demonstrated previously that restoration of chromosome 18 suppressed growth of pancreatic cancer cells in vitro, as well as that of tumors inoculated into nude mice. We also demonstrated that loss of 18q was associated with poor prognosis. Hence there is the possibility that the 18q arm harbors a gene(s) implicated in tumor progression and/or metastasis. In this study, we evaluated the effect of restoring chromosome 18 on metastasis in a few human pancreatic cancer cell lines with and without inactivation of SMAD4. After microcell-mediated chromosome 18 transfer, hybrid cells showed more than a 10-fold weaker metastatic ability than corresponding parental cells; mice injected with 1.25 x 10(6)/250 micro l hybrid clones via tail vein had less than one-tenth of the number of macroscopic metastases in the lung when compared with the control cells. Microscopic examination confirmed the decrease in the number of metastatic lesions. After inoculation of hybrid cells, more than 80% of the high-power fields showed no micrometastases, contrasting with their abundance after using the parental cells. Hybrid cells restored maspin expression irrespective of SMAD4 status in corresponding parental cells. On the other hand, significantly lower vascular endothelial growth factor and matrix metalloproteinase 2 secretion was observed by measuring levels in the conditioned media (CM); the averages were 22% and 20%, respectively. Angiogenesis assays using in vivo Matrigel plugs demonstrated that less neovascularization was observed in nude mice with hybrid cells than with corresponding parental cells. When cells were treated with CM from hybrids, the migration of human umbilical vascular endothelial cells was decreased, but it was partially restored with anti-vascular endothelial growth factor neutralizing antibody, as compared with CM from parental cells. These data represent the first functional evidence suggesting that chromosome 18q encodes a gene that strongly suppresses metastatic activity, possibly through dormancy.

Identification and characterization of novel rat and human gonad-specific organic anion transporters.

We have isolated three novel organic anion transporter cDNAs designated rat GST-1 (gonad-specific transporter), rat GST-2, and human GST, expressed at high levels in the testis. Rat GST-1, GST-2, and human GST consist of 748, 702, and 719 amino acids, respectively, and all molecules possess the 12 predicted transmembrane domains, which is a common structure of organic anion transporters. Northern blot analyses and in situ hybridization revealed that both of the rat molecules are highly expressed in the testis, especially in Sertoli cells, spermatogonia, and Leydig cells. Weak signals are also detected in the epididymis and ovary in adult rat. The exclusive expression of human GST mRNA in the testis was confirmed by RT-PCR. The pharmacological experiments of Xenopus laevis oocytes injected with the respective rat GST-1- and GST-2-cRNAs revealed that both rat GST-1 and GST-2 transport taurocholic acid, dehydroepiandrosterone sulfate, and T4 with Michaelis-Menten kinetics (taurocholic acid, Km = 8.9 and 2.5 microm, dehydroepiandrosterone sulfate, Km = 25.5 and 21.microm, and T4, Km = 6.4 and 5.8 for rat GST-1 and GST-2, respectively). T3 was also transported by rat GST-1 and GST-2. These data suggest that rat GST-1 and GST-2 might be one of the molecular entities responsible for transporting dehydroepiandrosterone sulfate and thyroid hormones involved in the regulation of sex steroid transportation and spermatogenesis in the gonad.

[Clinicopathological aspects of pancreatic cancer].

Using the nationwide database of the Japan Pancreas Society (JPS), the clinicopathological features of 23,284 cases (1981-2000) and 2,298 cases (2001-2002) with pancreatic neoplasms were compared. Intraductal papillary mucinous neoplasms and mucinous cystic neoplasms were increased in the registry. More detailed histological repertoires of endocrine tumors, intraductal tubular tumors and solid-pseudopapillary tumors were registered in the last two years. The numbers of serous cystadenocarcinomas and carcinomas in situ were decreased. The proportion of less differentiated adenocarcinoma was increased in the more advanced stages of the disease. In Stage IVa, the survival of the patients with papillary adenocarcinoma was not statistically different from that of patients with well or moderate tubular adenocarcinoma, though the difference was significant in earlier stages. The survival of the patients with poorly differentiated adenocarcinoma, adenosquamous carcinoma and undifferentiated carcinoma was miserable. Histological confirmation is critically important to prospect the outcome and to determine the treatment modality. Integration of the nationwide registry and pathological information will give new insights for the treatment of pancreatic cancer.

Specific and effective targeting cancer immunotherapy with a combination of three bispecific antibodies.

For the purpose of establishing a new adoptive immunotherapy for bile duct carcinoma (BDC), we previously constructed two kinds of bispecific antibodies (bsAbs), anti-MUC1 x anti-CD3 (M x 3) and anti-MUC1 x anti-CD28 (M x 28), which activate T cells and form bridges between them and MUC1-expressing tumor cells. In our previous studies [Cancer Res. 56 (1996) 4205] specific targeting therapy (STT) consisting of i.v. administration of lymphokine activated killer cells with a T cell phenotype (T-LAK) sensitized with two kinds of bsAbs to human BDC-grafted severe combined immunodeficient (SCID) mice demonstrated remarkable inhibition of tumor growth. However, complete cures could not be obtained. In order to improve antitumor efficacy, we have paid attention to anti-CD2 monoclonal antibodies (mAbs), thought to play an important roles in signal transduction in T cell activation or control of T cell receptor (TCR)-driven activation. Therefore, we developed another bsAb, anti-MUC1 x anti-CD2 (M x 2), in order to examine if this would show synergism with the two previously described bsAbs. The combination of the three bsAbs (M x 3, M x 28 and M x 2 bsAbs) showed highest cytotoxicity against MUC1-expressing BDC cells when given simultaneously with peripheral blood mononuclear cells (PBMCs) or T-LAK cells in vitro. When 2 x 10(7) T-LAK cells sensitized with different combinations of bsAbs were administered four times i.v. to BDC-grafted SCID mice, the best therapeutic result was obtained with a combination of all three bsAbs. These results indicate usefulness of combination of three bsAbs for targeting cancer immunotherapy.

Increased expression of HIP/PAP and regenerating gene III in human inflammatory bowel disease and a murine bacterial reconstitution model.

Although microorganisms play a role in gut inflammation, it remains uncertain which epithelial genes are expressed in response to luminal flora and whether these molecules are also involved in pathologic mucosal inflammation. Germ-free mice were orally challenged with a bacterial suspension prepared from conventionally housed mice (bacterial reconstitution). Thereafter, the differential gene expression in gut epithelial cells was identified by differential display. The expression of the identified genes was also examined in dextran sulfate sodium (DSS)-induced colitis and human inflammatory bowel disease (IBD) epithelial cells. Regenerating gene III (Reg III) was strongly induced in gut epithelial cells following bacterial reconstitution, as well as in the colitis initiated by DSS. The mRNA expression of hepatocarcinoma-intestine-pancreas/pancreatic associated protein (HIP/PAP), a human counterpart of Reg III, was enhanced in colonic epithelial cells of patients with IBD. Reg III mRNA expression was localized in the epithelial cells including goblet cells and columnar cells in mice; on the other hand, HIP/PAP-expressing cells were correlated with Paneth cell metaplasia in human colon. Epithelial expression of Reg III or HIP/PAP was induced under mucosal inflammation initiated by exposure to commensal bacteria or DSS as well as inflamed IBD colon.

Peritoneal inflammatory cells in acute pancreatitis: Relationship of infiltration dynamics and cytokine production with severity of illness.

BACKGROUND: The purpose of this study was to clarify the still poorly understood dynamics of peritoneal inflammatory cells (PICs) in acute pancreatitis. METHODS: Acute pancreatitis of 3 different degrees of severity was induced in male Wistar rats. Peritoneal lavage was performed at 1, 6, 12, and 24 hours after the induction, and the fluids collected were analyzed for the number and subpopulation of PICs. The levels of apoptosis and necrosis, cytokines, and bacterial infection were also investigated. RESULTS: The number of PICs was increased in mild and moderate pancreatitis, and the infiltration of inflammatory cells had occurred. In severe pancreatitis, the number of PICs increased until 6 hours after the induction, but thereafter the number decreased. Infiltration of neutrophils occurred 6 hours after the induction, but it was not sustained thereafter and infiltration of peritoneal macrophages did not occur. Cytokines in the lavage fluid increased in all 3 models during the first 6 hours after the induction. Subsequently, cytokines were reduced in mild and moderate pancreatitis but significantly increased in severe pancreatitis. The level of bacterial infection increased according to the severity. CONCLUSIONS: The relationship between the PIC dynamics and cytokine levels in severe pancreatitis is very different from that observed in mild or moderate pancreatitis.

Clinical evaluation of oral administration of a cholecystokinin-A receptor antagonist (loxiglumide) to patients with acute, painful attacks of chronic pancreatitis: a multicenter dose-response study in Japan.

INTRODUCTION: Cholecystokinin (CCK)-receptor antagonists have been found to markedly reduce the severity of pancreatitis and improve survival in experimental animal models of acute pancreatitis. CCK appears to play an important role in the development and progression of acute pancreatitis, and the recent development of CCK antagonists has provided a new approach to the treatment of acute pancreatitis in humans. AIMS: The therapeutic efficacy of a CCK-A receptor antagonist, loxiglumide, in patients with painful acute attacks of chronic pancreatitis was evaluated. METHODOLOGY: A multicenter dose-response controlled trial was conducted at 110 institutions in Japan from June 1993 to December 1994. Chronic pancreatitis was diagnosed for all patients on the basis of the Japanese criteria for chronic pancreatitis. Two-hundred seven patients were randomized to oral treatment with loxiglumide (300, 600, and 1,200 mg/d) or placebo for 4 weeks. The efficacy of treatment was evaluated on the basis of clinical symptoms, physical signs, and serum pancreatic enzyme levels. The groups were comparable with respect to age, sex, etiology, complications, and previous treatment. RESULTS: The improvement rate of the abdominal and/or back pain was 46% in the loxiglumide 300-mg group, 59% in the 600-mg group, and 52% in the 1,200-mg group, and it was 36% in the placebo group (600 mg versus placebo: p < 0.05). The physical signs evaluated--abdominal tenderness and resistance--improved in all three loxiglumide groups, and the serum pancreatic amylase and trypsin levels decreased significantly in the 600-mg group (p < 0.05). The overall clinical improvement rate was 46% in the 300-mg loxiglumide group, 58% in the 600-mg group, and 52% in the 1,200-mg group, and it was 34% in the placebo group. CONCLUSION: These results indicate that oral administration of loxiglumide may be useful in the treatment of patients with acute, painful attacks of chronic pancreatitis, and 600 mg/d is recommended as a beneficial dosage.

Octreotide in control of multiple liver metastases from gastrinoma.

The somatostatin analogue octreotide was effective in controlling systemic effects related to multiple liver metastases from a gastrinoma. A 61-year-old man underwent distal gastrectomy for gastrinoma in the duodenum, because a curative resection was not feasible due to metastases found in paraaortic lymph nodes during operation. Multiple liver metastases, associated with an increase in serum gastrin concentration, were found by magnetic resonance imaging 16 months after the operation. Although chemotherapy with dimethyltrizenoimidazole carboxamide was not effective, subcutaneous administration of octreotide was effective in controlling the growth of the liver metastases and in stabilizing serum gastrin. The patient now receives subcutaneous injections of octreotide, at 200 microg a day, twice a week, as an outpatient.

Effect of ileo-jejunal transposition on ileal longitudinal smooth muscle contractility in vitro in rats.

The aim of the present paper was to study the effects of ileo-jejunal transposition (IJT) on ileal contractile activity in vitro in rats. Male Sprague-Dawley rats were divided into three groups: control, IJT, and sham. In rats with IJT, the distal ileum was interposed isoperistaltically into the proximal jejunum. The jejunoileum was transected and anastomosed at three sites in the sham group. Rats were sacrificed 17-20 weeks postoperatively and the ileal segment was removed. Isometric contractile activity of the isolated ileal longitudinal muscle was measured in tissue chambers. Spontaneous contractile activity was decreased in the IJT group (0.16 +/- 0.03 g/min per mg tissue) as compared with the control group (0.25 +/- 0.02 g/min per mg tissue, p < 0.05). The motor response to cholinergic agonist bethanechol in the IJT group was greater than in the control group above 10(-6) M dosage. The dose-response curves to adrenergic agonist norepinephrine did not differ between groups. A nitric oxide synthase inhibitor reversed electrical field stimulation-induced inhibition of spontaneous activity in all groups. These results indicate that the response to bethanechol in the IJT group was enhanced in rat ileal longitudinal smooth muscle and this may be an adaptive response to compensate for decreased spontaneous contractile activity.

A new free radical scavenger, edaravone, ameliorates oxidative liver damage due to ischemia-reperfusion in vitro and in vivo.

Ischemia-reperfusion injury causes oxidative stress producing reactive oxygen species, which is a serious problem linked to morbidity and mortality in liver surgery. We investigated the effects of edaravone, a new free radical scavenger, on liver oxidative stress in vitro and in vivo. We employed a hypoxia-reoxygenation model of primary cultured hepatocytes using an AnaeroPack (Mitsubishi Gas Chemical Co., Tokyo, Japan). Hepatocytes were exposed to 3 or 4 hours of hypoxia and then returned to oxygenation. We analyzed the time course changes of aspartate aminotransferase (AST), phosphatidylcholine hydroperoxide (PCOOH), and adenosine triphosphate (ATP) content in hepatocytes of edaravone-treated groups or nontreated groups after reoxygenation. Edaravone significantly attenuated the elevation of the AST level of the medium and hepatocellular PCOOH and preserved the hepatocellular ATP level. In vivo, male Sprague-Dawley rats were subjected to 45 minutes of hepatic ischemia and 120 minutes of reperfusion. The rats were intravenously injected with vehicle or edaravone (3 mg/kg or 10 mg/kg) before reperfusion and 1 hour after reperfusion. Serum AST levels and hepatic PCOOH and energy charge were significantly improved in both edaravone groups compared with control. In conclusion, edaravone has the ability to eliminate intra-hepatocellular superoxide species and attenuate oxidative liver damage in liver surgery.

TU12B1-TY, a novel gene in the region at 12q22-q23.1 frequently deleted in pancreatic cancer, shows reduced expression in pancreatic cancer cells.

Loss of heterozygosity (LOH) on 12q is frequently observed in primary pancreatic cancer, as well as in cancers of other tissues such as stomach and germ cells. LOH correlates with poor prognosis in patients suffering from pancreatic cancer. In quest of tumor suppressor genes in this region, we used bacterial artificial chromosome (BAC) clones to construct a contig to cover one of the two targeted regions previously detected in pancreatic cancer; this region, 12B, is no larger than 650-kb between D12S360 and D12S78 at 12q22-q23.1. While constructing a detailed physical map and placing expressed sequence-tags, we identified a novel human gene, TU12B1-TY. This gene consisted of at least 14 exons and harbored an open reading frame possibly encoding a 473 amino-acid protein. A motif prediction program revealed a transmembrane domain in its carboxyl terminus. Expression in human tissues was found in the brain, placenta, skeletal muscle, pancreas, testis, uterus, and small intestine. In 21 pancreatic cancer cell lines analyzed, we found no structural alteration but all of them showed reduced expression. The present results indicate that reduced function of TU12B1-TY may contribute to the development and/or progression of human pancreatic cancer.

Thymidine phosphorylase expressed in macrophages enhances antitumor effect of 5'-deoxy-5-fluorouridine on human colorectal carcinoma cells.

BACKGROUND: Thymidine phosphorylase (dThdPase) is a key enzyme in the activation of the pro-drugs of 5-fluorouracil (5-FU), 5-deoxy-5-fluorouridine (5'-DFUR) and capecitabine. In colorectal carcinoma (CRC), the major cells expressing dThdPase have been shown to be stromal cells, particularly macrophages. MATERIALS AND METHODS: The present study was designed to clarify whether dThdPase expressed in macrophage-like cell lines, THP-1 and U937, and monocyte-rich mono-nuclear cells (MoMNCs) from human peripheral blood can modulate the antitumor effect of 5'-DFUR on CRC cells. RESULTS: dThdPase protein was found in THP-1 and U937 by ELISA, while little or no dThdPase could be detected in the CRC cell lines tested. Incubation of 5'-DFUR with the macrophage-like cells significantly enhanced the antitumor effect of 5'-DFUR in a 5-DFUR sensitivity assay compared with untreated 5'-DFUR. MoMNCs also showed a similar effect. When the media containing 5'-DFUR was treated with either THP-1 or U937 cells, detectable levels of 5-FU could be measured in the treated media. CONCLUSION: These data suggest that macrophages convert 5'-DFUR to 5-FU and release the converted 5-FU, resulting in an enhancement of the antitumor effect of 5'-DFUR.

Expression of thymidine phosphorylase by macrophages in colorectal cancer tissues.

AIM: To detect the thymidine phosphorylase (dThdPase) expression in human colorectal cancer tissues and cells. METHODS: Forty specimens resected from patients with colorectal cancer were immunohistochemically stained by 654-1, anti-dThdPase monoclonal antibody, PG-M1, anti-macrophage marker CD68 monoclonal antibody. Morphometrical analysis and positive cell counting were performed. In 27 of 40 specimens, dThdPase activity was also assayed by HPLC. Otherwise, the dThdPase level was measured by ELISA in 6 colorectal cancer cell lines, LS174T, Clone A, Colo320, CX-1, Lovo, and MIP101, as well as in 2 macrophage-like cell lines, THP-1 and U937. RESULTS: dThdPase activity was significantly increased in cancer tissues compared with adjacent normal tissue (P<0.01). In immunohistochemical analysis, it was confirmed that most cells expressed dThdPase were the stromal cells surrounding cancer nests or along the invasive margin of cancer. Based on their morphometrical characteristics, we found that most of them were tumor-associated macrophages (TAMs). The number of dThdPase-positive stromal cells was significantly correlated with the number of CD68-positive macrophages (r=0.76, P<0.0001). By ELISA, 18.2 unit/mg and 19.3 unit/mg of dThdPase protein were detected in THP-1 and U937, but only little was detected in 6 colorectal cancer cell lines. CONCLUSION: The present data suggest that dThdPase expression is seldom detected in colorectal carcinoma cells. TAM is the most important source of dThdPase in colorectal cancer tissues.

Gene therapy for pancreatic cancer targeting the genomic alterations of tumor suppressor genes using replication-selective oncolytic adenovirus.

In order to develop an effective therapeutic intervention for patients with pancreatic cancer, we examined the genetic alternations of pancreatic cancer. Based on these results, we are developing a new gene therapy targeting the genetic character of pancreatic cancer using mutant adenoviruses selectively replication-competent in tumor cells. Loss of heterozygosity (LOH) of 30% or more were observed on chromosome arms 17p (47%), 9p (45%), 18q (43%), 12q (34%), and 6q (30%). LOH of 12q, 17p, and 18q showed the significant association with poor prognosis. These data strongly suggest that mutation of the putative suppressor genes, TP53 and SMAD4 play significant roles in the disease progression. Based on this rationale, we are developing a new gene therapy targeting tumors without normal TP53 function. E1B-55kDa-deleted adenovirus (AxE1AdB) can selectively replicate in TP53-deficient human tumor cells but not cells with functional TP53. We evaluated the therapeutic effect of this AxE1AdB on pancreatic cancer without normal TP53 function. The growth of human pancreatic tumor in SCID mice model was markedly inhibited by the consecutive injection of AxE1AdB. Furthermore, AxE1AdB is not only the strong weapon but also useful carrier of genes possessing anti-tumor activities as a virus vector specific to tumors without normal TP53 function. It was reported that uracil phosphoribosyl transferase (UPRT) overcomes 5FU resistance. UPRT catalyzes the synthesis of 5-fluorouridine monophosphate (FUMP) from Uracil and phosphoribosylpyrophosphate (PRPP). The antitumor effect of 5FU is enhanced by augmenting 5-fluorodeoxyuridine monophosphate (FdUMP) converted from FUMP, which inhibits Thymidylate Synthetase (TS). The therapeutic advantage of restricted replication competent adenovirus that expresses UPRT (AxE1AdB-UPRT) was evaluatedin an intra-peritoneal disseminated tumor model. To study the anti-tumor effect of AxE1AdB-UPRT/5FU, mice with disseminated AsPC-1 tumors were administered the adenovirus, followed by the 5FU treatment. It was shown that the treatment with AxE1AdB-UPRT/5FU caused a dramatic reduction of the disseminated tumor burden without toxicity in normal tissues. These results revealed thatthe AxE1AdB-UPRT/5FU system is a promising tool for intraperitoneal disseminated pancreatic cancer.

Changes of hepatic sinusoids in experimental septicemia of rats are correlated with the production of nitrogen monoxide. A morphometrical and immunohistochemical study.

BACKGROUND/AIMS: Two types of experimental septic models were prepared to morphologically and histometrically analyze the changes in the hepatic sinusoid. Furthermore, the local expression of nitrogen monoxide synthetase was analyzed by immunohistochemical and immune electron microscopical studies for the purpose of investigating the involvement of nitrogen monoxide in these changes. METHODOLOGY: Using Sprague-Dawley strain male rats, two types of experimental septic models were prepared. These were a bacterial peritonitis model induced by a cecal ligation and puncture method, and a peritonitis model after intraperitoneal administration of endotoxin at 10 mg/kg. Serum alanine aminotransferase and endotoxin were measured in due order. The liver tissues were sampled and examined by usual light microscopical and electron microscopical analyses. The sites of the portal and central vein regions were randomly selected, and the sinusoidal cavity/liver volume ratio was estimated by the point counting method under high magnification. In addition, the expressions of nitrogen monoxide synthetase were investigated in the collected samples of the liver, lung and aortic wall. RESULTS: According to the histometrical analysis of the sinusoid, the sinusoidal cavity volume ratio at 6 hours after the onset increased from 0.0690 +/- 0.0147 to 0.089 +/- 0.004 in the central vein region. The ratio rapidly increased from 0.058 +/- 0.009 to 0.093 +/- 0.008 in the portal region from 6 to 12 hours after the onset. The values of serum alanine aminotransferase and endotoxin were significantly increased from 6 to 12 hours after the onset of peritonitis. The inducible nitrogen monoxide synthetase was observed in the alveolar macrophages, monocytes, and hepatic Kupffer cells from 6 to 12 hours after the onset of peritonitis. CONCLUSIONS: These results demonstrated that the sinusoidal cavity became dilated in the sepsis model and at the same time nitrogen monoxide synthetase was expressed in the sinusoidal wall-composing cells. There is a possibility that the action of nitrogen monoxide is involved in the changes in the volume of the sinusoidal cavity, suggesting the involvement of nitrogen monoxide derived from sinusoidal wall-composing cells in the hepatic dysfunction caused by sepsis in addition to nitrogen monoxide generation from Kupffer cells.