Genetic variations and microbiome of the poultry red mite Dermanyssus gallinae.

The poultry red mite Dermanyssus gallinae poses a significant threat to the health of hens and poultry production. A comprehensive understanding of D. gallinae is necessary to develop sustainable and efficacious control methods. Here we examined 144 D. gallinae collected from 18 poultry farms throughout the Japanese Archipelago for their genetic variations based on mitochondrial cytochrome c oxidase subunit I (COI) sequences, and microbiome variations based on amplicon sequencing of the 16S ribosomal RNA gene. According to COI sequencing, the Japanese samples were categorized into three haplogroups, which did not reflect the geographical distribution. Microbiome analyses found that the major bacteria associated with D. gallinae were Bartonella, Cardinium, Wolbachia, and Tsukamurella, with Bartonella being most predominant. Among 144 individual mites, all possessed one of the two major types of Bartonella (Bartonella sp. A), while 140 mites possessed the other type (Bartonella sp. B). The presence of the two strains of Bartonella was also confirmed by a single copy gene, rpoB. The presence of Bartonella in laid eggs suggested transovarial vertical transmission. Given that obligate blood-feeding arthropods generally require a supply of B vitamins from symbiotic bacteria, Bartonella may play an important role in mite survival. Rickettsiella, a major symbiont in European D. gallinae populations, and suggested to be an important symbiont by genomic data, was rarely found in Japanese populations. Cardinium detected from D. gallinae fell into a major clade found widely in arthropods, whereas Wolbachia detected in Japanese D. gallinae appear to be a new lineage, located at the base of Wolbachia phylogeny. Of the mitochondrial phylogeny, infection patterns of Cardinium and Wolbachia were strongly correlated, possibly suggesting one or both of the symbionts induce reproductive manipulations and increase spread in the host populations.

Effects of fungal pancreatic enzymes on the function of islet cells in Syrian golden hamsters.

CONTEXT: Our previous studies showed that porcine pancreatic enzymes in Syrian golden hamsters with peripheral insulin resistance normalizes the plasma insulin level, reduces the size of enlarged islets and inhibits the increased DNA synthesis in the beta-cell of islets. OBJECTIVE: In order to exclude the possibility that these effects was attributed to some contaminants of this crude material, we tested the effect of purified fungal pancreatic enzyme (FPE) that contains primarily amylase and lipase without (FPE) and with addition of chymotrypsin (FPE+chy). MATERIAL AND METHODS: In a pilot study we tested the effect of different doses of FPE given in drinking water on insulin level, islet size and DNA synthesis of islet cells in hamsters with induced peripheral insulin resistance by a high fat diet. The most effective dose of FPE on these parameters was used in a long-term experiment with FPE and FPE+chy in hamsters fed a high-fat diet for 36 or 40 weeks. RESULTS: In the pilot study a dose of 2 g/kg body weight was found to be optimal for controlling the body weight, normalizing plasma insulin level, the size of islets, the DNA synthesis and the number of insulin cells in the islets. These data were produced in the long-term study, where steatorrhea was also inhibited. Addition of chymotrypsin had no effects on these parameters. CONCLUSION: Pancreatic lipase and amylase appear to be responsible for the observed effects and offer a safe and effective natural product for the treatment of pancreatic diseases, including acute pancreatitis, chronic pancreatic, cystic fibrosis and any conditions associated with peripheral insulin resistance, including obesity and type 2 diabetes. The possible mechanism of the action is discussed.

Effects of porcine pancreatic enzymes on the pancreas of hamsters. Part 2: carcinogenesis studies.

CONTEXT: Our previous study suggested that porcine pancreatic extract in hamsters with peripheral insulin resistance, normalizes insulin output, islet size and pancreatic DNA synthetic rate. It also inhibited the growth of human pancreatic cancer cells in nude mice. OBJECTIVE: To examine the potential value of the porcine pancreatic extract in controlling pancreatic carcinogenesis in this model, the present experiment was performed. DESIGN: Hamsters were fed a high fat diet and four weeks later when insulin resistance emerges, they were divided into two groups. One group received 1 g/kg BW of porcine pancreatic extract in drinking water and the other group received tap water. One week later, when insulin output normalizes in porcine pancreatic extract-treated hamsters, a single subcutaneous injection of N-nitrosobis-(2-oxopropyl) amine (BOP) at a dose of 40 mg/kg BW was given to all hamsters. The experiment was terminated at 43 weeks after the porcine pancreatic extract treatment. The number and size of pancreatic tumors, blood glucose, insulin, amylase and lipase levels, the average size of islets and the number of insulin cells/islets were determined. RESULTS: The incidence of pancreatic cancer was significantly lower in the porcine pancreatic extract group (P=0.043), as well as the plasma insulin level and the size of the islets in the porcine pancreatic extract group were significantly lower (P<0.001) than in the control group. No significantly differences were found in the glucose level between the groups. CONCLUSION: These results show that porcine pancreatic extract has a potential to inhibit pancreatic cancer growth.

MEK1 and MEK2 isoforms regulate distinct functions in pancreatic cancer cells.

The mitogen-activated protein kinase kinase 1/2 (MEK1/2) signalling pathway plays a central role in tumour progression. Small molecules that inhibit MEK1/2 are therefore considered attractive candidates for anti-cancer drugs. However, the exact contributions of MEK1 and MEK2 to the development of pancreatic cancer remain to be established. To differentiate the functions of MEK1 and MEK2 in a cultured pancreatic cancer cell line, we utilised shRNA-mediated knockdown of their two mRNAs individually. We studied the effects of MEK1 and MEK2 knockdown on cell morphology, proliferation, mitotic arrest, and in vitro invasion capability in PC-1.0 cells. The results showed that inhibition of MEK1 expression was an effective and specific approach to inhibit cell proliferation and induce G0/G1 arrest. On the other hand, MEK2 knockdown specially altered cell morphology and inhibited the invasive ability of pancreatic cancer cells. Therefore, MEK1 and MEK2 mediate different biological responses in cultured pancreatic cancer cells. These proteins could become distinct targets for the inhibition of specific cellular functions in the treatment of pancreatic cancer.

Genomic analysis of invasion-metastasis-related factors in pancreatic cancer cells.

Pancreatic cancer is known to be an extremely lethal neoplasm, one of the reasons being that pancreatic cancer itself has an extremely high potential of invasion-metastasis. In our previous study, two pancreatic cancer cell lines with a different potential for invasion-metastasis, PC-1 with a low potential and PC-1.0 with a high potential of invasion-metastasis after intrapancreatic transplantation, were established in a Syrian golden hamster. To determine the invasion-metastasis-related factors, a cDNA microarray that represented a set of 27,000 genes was hybridized with a labeled cDNA probe and screened for molecular profiling analysis. Furthermore, Gene Ontology and Pathway differential expression of candidate genes was further validated using RT-PCR. One hundred and forty-one differentially expressed genes (>3.0-fold change) were identified in the present study, including 46 up-regulated genes (e.g., nup107, tjp-2 and MMP-13) and 95 down-regulated genes (e.g., Spc21, plau and CD44) in the PC-1.0 cells. Our present results suggest that a highly organized and structured process of tumor invasion-metastasis exists in the pancreas. Analysis of gene expression profiles by cDNA microarray provides useful information for clarifying the mechanism underlying this invasion and metastasis. Furthermore, the identification of invasion-metastasis-specific genes may allow us to develop new therapeutic and diagnostic targets for the invasion-metastasis of pancreatic cancer.

An extremely oligotrophic bacterium, Rhodococcus erythropolis N9T-4, isolated from crude oil.

Rhodococcus erythropolis N9T-4, which was isolated from crude oil, showed extremely oligotrophic growth and formed its colonies on a minimal salt medium solidified using agar or silica gel without any additional carbon source. N9T-4 did not grow under CO(2)-limiting conditions but could grow on a medium containing NaHCO(3) under the same conditions, suggesting that the oligotrophic growth of N9T-4 depends on CO(2). Proteomic analysis of N9T-4 revealed that two proteins, with molecular masses of 45 and 55 kDa, were highly induced under the oligotrophic conditions. The primary structures of these proteins exhibited striking similarities to those of methanol: N,N'-dimethyl-4-nitrosoaniline oxidoreductase and an aldehyde dehydrogenase from Rhodococcus sp. These enzyme activities were three times higher under oligotrophic conditions than under n-tetradecane-containing heterotrophic conditions, and gene disruption for the aldehyde dehydrogenase caused a lack of growth on the minimal salt medium. Furthermore, 3-hexulose 6-phosphate synthase and phospho-3-hexuloisomerase activities, which are key enzymes in the ribulose monophosphate pathway in methylotrophic bacteria, were detected specifically in the cell extract of oligotrophically grown N9T-4. These results suggest that CO(2) fixation involves methanol (formaldehyde) metabolism in the oligotrophic growth of R. erythropolis N9T-4.

Combined radical retropubic prostatectomy and abdominoperineal excision of the rectum for locally invasive rectal cancer as a less invasive surgery: report of a case.

The optimal therapy for carcinoma of the rectum with invasion of the prostate gland has not been established. For a patient who has rectal carcinoma invading into the prostate and seminal vesicles and not invading into any other pelvic viscera, we performed combined radical retropubic prostatectomy and abdominoperineal excision of the rectum with reconstruction of the urinary tract by anastomosis of the ureter to the bladder. En bloc excision yielded negative surgical margins. After the operation, the patient had an infection of the abdominal wound and leakage of the anastomosis of the urethra to the bladder. These complications were treated conservatively and improved without becoming critical. The patient now has satisfactory postoperative function of voiding. This technique obviates the need for urinary diversion or urinary reconstruction such as the neobladder in the case of total pelvic exenteration. We consider this procedure is of benefit for improving the quality of life of patients with rectal cancer invading into the prostate.

The potential role of DFNA5, a hearing impairment gene, in p53-mediated cellular response to DNA damage.

The tumor suppressor p53 plays a crucial role in the cellular response to DNA damage by transcriptional activation of numerous downstream genes. Although a considerable number of p53 target genes have been reported, the precise mechanism of p53-regulated tumor suppression still remains to be elucidated. Here, we report a novel role of the DFNA5 gene in p53-mediated etoposide-induced cell death. The DFNA5 gene has been previously reported to be responsible for autosomal-dominant, nonsyndromic hearing impairment. The expression of the DFNA5 gene was strongly induced by exogenous and endogenous p53. The chromatin immunoprecipitation assay indicated that a potential p53-binding sequence is located in intron 1 of the DFNA5 gene. Furthermore, the reporter gene assay revealed that the sequence displays p53-dependent transcriptional activity. The ectopic expression of DFNA5 enhanced etoposide-induced cell death in the presence of p53; however, it was inhibited in the absence of p53. Finally, the expression of DFNA5 mRNA was remarkably induced by gamma-ray irradiation in the colon of p53(+/+) mice but not in that of p53(-/-) mice. These results suggest that DFNA5 plays a role in the p53-regulated cellular response to genotoxic stress probably by cooperating with p53.

Successful treatment of malignant fibrous histiocytoma originating in the chest wall: report of a case.

Malignant fibrous histiocytoma (MFH) rarely originates in the chest wall, so its clinical features are not well defined. We report a case of MFH that recurred locally 3 years after primary resection. The patient, a 59-year-old woman, underwent wide excision, and is alive without recurrence 7 months after the operation. We reviewed the clinical features and treatment strategies of the total 39 cases of MFH originating in the chest wall reported from Japan. The fact that all patients who underwent wide excision with negative margins at the primary operation were alive without recurrence at the time of each report, despite a local recurrence rate as high as 40%, shows the importance of this operative strategy. Thus, early diagnosis of MFH of the chest wall is essential for improving the outcome of these patients. Neoadjuvant chemotherapy plus radiation therapy may be worthwhile for patients with advanced disease.

Loss of expression of type IV collagen alpha5 and alpha6 chains in colorectal cancer associated with the hypermethylation of their promoter region.

Type IV collagen, a major component of the basement membrane (BM), is composed of six genetically distinct alpha(IV) chains, alpha1(IV) to alpha6(IV). Their genes are paired on three different chromosomes in a head-to-head arrangement. The alpha5(IV) gene (COL4A5) and the alpha6(IV) gene (COL4A6) are on chromosome Xq22 and are regulated by a bidirectional promoter. Loss of the alpha5(IV)/alpha6(IV) chains in epithelial BM occur in the early stage of cancer invasion. However, the regulatory mechanism of the specific loss of the alpha5(IV)/alpha6(IV) chains during cancer cell invasion is still undetermined. In the present study, we examined the expression of the alpha5(IV)/alpha6(IV) chains and the methylation profiles of the bidirectional promoter region of COL4A5/COL4A6 in colon cancer cell lines and colorectal tumor tissues. The expression of the alpha5(IV)/alpha6(IV) chains was down-regulated in colorectal cancer, and the loss of expression of the alpha5(IV)/alpha6(IV) chains was associated with the hypermethylation of their promoter region. In conclusion, the hypermethylation of the bidirectional promoter region of COL4A5/COL4A6 is one of the events that is responsible for the loss of expression of the alpha5(IV)/alpha6(IV) chains and the remodeling of the epithelial BM during cancer cell invasion.

Signal of proteinase-activated receptor-2 contributes to highly malignant potential of human pancreatic cancer by up-regulation of interleukin-8 release.

Proteinase-activated receptor-2 (PAR-2) is expressed in various tissues, including cancer lesions. However, the functional consequences of PAR-2 expression in cancer cells, especially in pancreatic cancer cells, are poorly understood. To clarify the biological significance of PAR-2 signaling in pancreatic cancer, we examined the production of growth factors and cytokines, such as IL-6, IL-8, bFGF, TGF-beta1, and VEGF, by specific ELISAs. Two human pancreatic cancer cell lines, SUIT2 and MiaPaCa2, which have been shown to express PAR-2, were stimulated by trypsin and PAR-2 activating peptide (PAR-2AP: SLIGKV-NH2). After 24 h, the culture supernatants were collected and specific ELISAs were performed. Although no significant changes were observed in the release of IL-6, bFGF, TGF-beta1, or VEGF, that of IL-8 was significantly up-regulated by PAR-2 agonists in a dose-dependent manner. In addition, IL-8 receptor expression was found in pancreatic cancer cells and fibroblasts. These results suggest that the PAR-2 signal up-regulates IL-8 release from pancreatic cancer cells. This up-regulated IL-8 has an effect on the pancreatic cancer cells in an autocrine manner and on the fibroblasts in a paracrine manner. Thus, this signal might contribute to tumor progression and characteristic fibrosis in pancreatic cancer.

Usefulness and clinical significance of quantitative real-time RT-PCR to detect isolated tumor cells in the peripheral blood and tumor drainage blood of patients with colorectal cancer.

The clinical significance of isolated tumor cells (ITC) circulating in the blood of patients with colorectal cancer is unclear. In this study, we investigated the relationship between the presence of ITC that express carcinoembryonic antigen (CEA) and/or cytokeratin 20 (CK20) transcripts in the blood and the clinicopathological findings and prognosis using the quantitative real-time reverse transcription-polymerase chain reaction (RT-PCR) assay. We studied peripheral blood and tumor drainage blood from 167 patients with colorectal cancer. Quantitative real-time RT-PCR assay was able to detect one tumor cell in 3x10(6) peripheral blood mononuclear cells. Applying a cut-off value, CEA and/or CK20 (CEA/CK20) were detected in 10.2% (17/167) of the patients' preoperative peripheral blood samples and 34.1% (57/167) of the patients' tumor drainage blood samples. In the relationship between the CEA/CK20 of the blood and the clinicopathological factors, a significant correlation was demonstrated between the positivity of marker genes and the depth of invasion, venous invasion, lymph node metastasis, liver metastasis or stage. The disease-free and overall survival of patients with CEA/CK20-positive peripheral or tumor drainage blood was significantly shorter than that of marker gene-negative patients. CEA/CK20 transcripts in tumor drainage blood were independent factors for prognosis in disease-free survival and overall survival. These results suggest that detecting CEA/CK20 mRNA in tumor drainage blood by real-time RT-PCR has prognostic value in patients with colorectal cancer. Large scale and long-term clinical studies are needed to confirm the prognostic value of genetically detecting ITC in the peripheral blood.

Analysis of the invasion-metastasis mechanism in pancreatic cancer: involvement of plasmin(ogen) cascade proteins in the invasion of pancreatic cancer cells.

To clarify the potential involvement of plasmin(ogen) cascade proteins in the cell dissociation and subsequent invasion of pancreatic cancer cells, western blot analysis, immunocytochemistry, immunohistochemistry, and in vitro invasion assay were performed in the cell lines or tissue of pancreatic cancer. The strong expression of plasmin(ogen), urokinase type plasminogen activator (uPA) and uPA receptor (uPAR), and apparently weak expression of the relevant proteins were found in the conditioned medium of dissociated (PC-1.0) and non-dissociated (PC-1) pancreatic cancer cells, respectively. Furthermore, uPA-treatment significantly induced the expression of plasmin(ogen) and uPAR in the conditioned medium of non-dissociated (PC-1) pancreatic cancer cells. Moreover, the expression of plasmin(ogen) and uPAR was stronger at the invasive front than at the center of human pancreatic cancer tissue. On the other hand, plasmin-treatment induced the expression of matrix metalloproteinase-2 (MMP-2), MMP-7 and MMP-9 in PC-1 cells. Simultaneously, plasmin- or uPA-treatments obviously induced the dissociation of cell colonies and in vitro invasiveness in PC-1 cells. The plasmin(ogen) cascade is closely involved in the invasion of pancreatic cancer cells and, especially in its early stage, cell dissociation. Targeting the plasmin(ogen) cascade may provide a new insight into molecular target therapy based on anti-invasion and anti-metastasis for pancreatic cancer.

[Local ablation therapy for hepatocellular carcinoma (HCC) on the liver surface: radio-frequency ablation aimed at tumor marginal pre-ablation under endoscopic surgery].

RFA for the hepatocellular carcinoma localized on the surface of the liver tends to have some complications such as bleeding, an ejection of tumor and a heat injury to other internal organs even if percutaneous RFA seemed to be done easily. Therefore, we should first choose the RFA treatment under endoscopic (either laparoscope or thoracoscope) surgery for the hepatocellular carcinoma localized on the surface of the liver. Moreover, a direct central puncture should be avoided from the viewpoint of securing a margin, prevention of bleeding and rise in the intratumorale pressure. Now, we selected the unique operation method of RFA: First, the tumor is confirmed under the endoscope, and the tumor range is marked with the endoscopic echo. Second, several times of RFA applied to the tumor surroundings are done, and the margin is secured with avoiding a direct central puncture. If tumor diameter is over 2.5 cm, central ablation of the tumor is considered to be necessary, we can directly puncture the center of the tumor without bleeding since the tumor already has the congelation by surrounding heat effect. We have done RFA by this way for 29 patients with HCC since April 1st, 2004. The complications such as a heat injury to the neighboring organ could be well prevented. An enough margin of ablation about 1 cm around the tumor was confirmed by the postoperative CT image. There was no local recurrence during the average observation period of 290 days, and a severe post operative complication has not occurred. The average of hospitalized period after the operation was about 10 days. Therefore, pre-surrounding ablation preceding central puncture under the endosope for hepatocellular carcinoma on the liver surface is a feasible technique.

[Hand-assisted laparoscopic adrenalectomy to a solitary adrenal metastasis from lung cancer].

A 75-year-old man with right chest pain was diagnosed with primary lung cancer in the right apical portion, and was treated with chemoradiotherapy because of a synchronous left adrenal tumor of 1.6 cm. Since the adrenal tumor did not increase in size for three months and there were no other relapses, the right upper lobectomy of the lung with the excision of the chest wall was performed. Afterward, an enlargement of the left adrenal tumor was encountered; he was admitted to our hospital for an operation. For the metastatic adrenal tumor from lung cancer, we performed a hand-assisted laparoscopic adrenalectomy. He recovered rapidly and returned to the previous hospital in two weeks after the operation. After the first report in 1992, the laparoscopic adrenalectomy has been established as the curative operation to adrenal benign tumor. The indication is being expanded to the malignancy because of the improvement of operation techniques and advancement of the operation equipments. We conclude that the laparoscopic adrenalectomy for malignant tumor is a safe, curative, and clinically useful surgical technique.

Clinical significance of MHC class II-associated invariant chain expression in human gastric carcinoma.

MHC class II antigens serve as restricted elements for cell presenting antigens to CD4+ helper T cells. CD4+ T cells and CD8+ cytotoxic T cells, which are tumor-infiltrating lymphocytes (TILs), and play a major role in the survey and attack against tumor cells in primary lesions. Invariant chain (Ii) has several functions in MHC class II-restricted antigen presentation. In addition, Ii is found to be closely involved in the regulation of anti-tumor immunity in several tumor types. However, the significance of Ii expression in tumor cells is not fully illustrated. Immunohistochemical staining of Ii expression was performed in 58 cases of human gastric carcinoma specimens. The prognostic analysis of patients with gastric carcinoma was also performed. A total of 67.2% (39/58) gastric carcinomas were found to be Ii-positive, whereas only 20.7% (12/58) showed positive immunoreactivity with anti-MHC class II determinants. Furthermore, Ii expression showed significant correlation with the differentiation of gastric carcinoma (p<0.05). Ii expression also showed an inverse correlation with the frequency of TILs around carcinoma tissues, as well as with the prognosis of gastric carcinoma (p<0.01). Ii expression is closely correlated with anti-tumor immunity in human gastric carcinoma. Therefore, Ii may serve as an independent clinical marker for poor biological behavior and prognostic analysis in patients with gastric carcinoma.

Zonula occludens-1 (ZO-1) redistribution is involved in the regulation of cell dissociation in pancreatic cancer cells.

In our previous study, dissociation factor (DF) and mitogen-activated protein kinase kinase 2 (MEK2) were isolated as factors relating to cancer cell dissociation in pancreatic cancer cells. On the other hand, tight junction protein zonula occludens 1 (ZO-1) has been indicated to be involved in carcinogenesis. In this study, the expression of ZO-1 and a downstream kinase of MEK2, extracellular signal-regulated kinase 2 (ERK2), was analyzed to clarify the regulatory mechanism of cell dissociation in pancreatic cancer cells. Two hamster (PC-1.0 and PC-1) and two human (AsPC-1 and CAPAN-2) pancreatic cancer cell lines were used. Immunocytochemical study was performed using anti-ZO-1, ERK2, and phosphorylated ERK1/2 (p-ERK1/2) antibodies. DF treatment obviously disrupted ZO-1 expression at the sites of cell-cell contact and markedly induced ERK2 and p-ERK1/2 expression, as well as the dissociation of cell clones in PC-1 and CAPAN-2 cells. In contrast, U0126 (a MEK1/2 inhibitor) treatment significantly induced the peripheral distribution of ZO-1 as well as cell aggregation in PC-1.0 and AsPC-1 cells, which usually grew as single cells, but seriously suppressed ERK2 and p-ERK1/2 expression. We conclude that redistribution of ZO-1 is closely correlated with cell dissociation status in pancreatic cancer cells through activation of ERK2.

Correlation of translocation of tight junction protein Zonula occludens-1 and activation of epidermal growth factor receptor in the regulation of invasion of pancreatic cancer cells.

Mitogen-activated protein kinase signal transduction pathway was isolated as a potential factor related to cancer cell dissociation in dissociated (PC-1.0 and AsPC-1) and non-dissociated (PC-1 and Capan-2) pancreatic cancer cells in our previous works. On the other hand, changes of structure and function of tight junction (TJ) are reported to be correlated with carcinogenesis and tumor development. In this study, the translocation of TJ protein Zonula occludens-1 (ZO-1) and the activation of epidermal growth factor receptor (EGFR) were examined to demonstrate the involvement and correlation of TJ protein translocation and EGFR activation in the cell dissociation and subsequent invasion of pancreatic cancer. Immunocytochemistry, fluorescence intensity analysis and in vitro invasion assay were performed in dissociated and non-dissociated pancreatic cancer cells. The obvious translocation of cell-cell junction localized ZO-1 protein to the cytoplasm and nucleus, simultaneous activation of EGFR, as well as the dissociation of cell colonies of non-dissociated pancreatic cancer cells were induced by dissociation factor treatment. However, EGFR inhibitor, AG1478, treatment significantly induced the redistribution of ZO-1 protein to the sites of cell-cell junction and the cell aggregation, as well as simultaneous suppression of EGFR activation in both the dissociated and the non-dissociated pancreatic cancer cells. In addition, AG1478 treatment markedly enhanced the in vitro invasion of non-dissociated pancreatic cancer cells. Translocation of TJ protein ZO-1 is closely involved in the induction of invasion through EGFR activation in pancreatic cancer cells.

Involvement of matrix metalloproteinase-7 in invasion-metastasis through induction of cell dissociation in pancreatic cancer.

Epidermal growth factor receptor (EGFR) mediated mitogen-activated protein kinase kinase (MEK)/extracellular signal-regulated kinase (ERK) signaling pathway was isolated as invasion-metastasis related factor in pancreatic cancer in our previous studies. Matrix metalloproteinase-7 (MMP-7) and tight junction (TJ) proteins are indicated to be involved in cancer invasion-metastasis. To clarify the underlying mechanism of involvement of MMP-7 in cancer invasion, western blotting, invasion assay and immunohistochemistry were performed in dissociated (PC-1.0 and AsPC-1) and non-dissociated (PC-1 and Capan-2) pancreatic cancer cells, as well as pancreatic cancer tissues. Intracellular MMP-7 protein presented as pre-proenzyme and its expression was decreased by AG1478 (EGFR inhibitor) or U0126 (MEK inhibitor) treatment in pancreatic cancer cells. Activated MMP-7 protein was only detected in the medium of PC-1.0 and AsPC-1 cells, but not detected in the medium of PC-1 and Capan-2 cells. Moreover, MMP-7 treatment significant induced the dissociation of cell colonies in PC-1 and Capan-2 cells. Synchronously, TJ structure was apparently disrupted and translocation of TJ proteins to cytoplasm or extracellular medium was induced in PC-1 and Capan-2 cells. Furthermore, MMP-7 treatment markedly increased the in vitro invasion of PC-1 and Capan-2 cells. In addition, MMP-7 expression at the invasive front was obviously stronger than that at the center of pancreatic cancer tissues. Activation of MMP-7 protein is closely involved in disruption of TJ structure and consequent induction of cell dissociation as well as invasion in pancreatic cancer. EGFR mediated MEK/ERK signaling pathway is implied to be involved in regulation of MMP-7 expression in pancreatic cancer cells.

[A case of bilateral multiple liver metastases with distant lymph node metastases due to rectal cancer successfully treated with hepatic arterial infusion (HAI) of levofolinate (l-LV)/5-fluorouracil (5-FU) and radiotherapy].

The patient was a 43-year-old male with bilateral multiple liver metastases, who had undergone high anterior resection for rectal cancer (ss, n 0, P 0, H 3, M (-), stage IV). Hepatic arterial infusion (HAI) of low-dose CDDP (10 mg/body) and 5-FU (250 mg/body), 5 times a week, was ineffective for the liver metastases. Consequently, HAI of levofolinate (425 mg/body) and 5-FU (1,000 mg/body), once a week, was attempted. All metastatic liver tumors diminished apparently with calcification after the treatment (PR). Tumor marker (CA19-9 and CEA) levels decreased to less than one-tenth of the pretreatment levels and stabilized for approximately seven months. Mediastinal lymph node metastases, paraaortic lymph node metastases and tumor thrombus in the inferior vena cava were successfully treated with systemic chemotherapy using levofolinate and 5-FU and/or radiotherapy. Although the liver and lung metastases showed rapid growth, the patient died 2 years after the diagnosis of liver metastases. The liver metastases were well controlled for about 20 months. It is important to select interdisciplinary therapies according to the site of the metastases due to rectal cancer.