A case of idiosyncratic liver injury after oxaliplatin-induced thrombocytopenia.

WHAT IS KNOWN AND OBJECTIVE: Oxaliplatin is a platinum drug used for treating digestive cancers that can lead to drug-induced thrombocytopenia (DITP). We report a case of oxaliplatin-induced anaphylaxis and DITP, complicated by idiosyncratic drug-induced liver injury (IDILI). CASE SUMMARY: A 46-year-old woman with rectal cancer developed anaphylaxis shortly after oxaliplatin administration (post-operative CapeOX), presenting with low platelet count (0.2 × 104 /µL) and elevated aspartate aminotransferase (1091 IU/L) and alanine aminotransferase (1010 IU/L) by day 10. Following 50 mg/d prednisolone administration from day 9, she left the hospital on day 36 after recovering. WHAT IS NEW AND CONCLUSION: This is the first case report of oxaliplatin-induced IDILI and its effective treatment with steroids.

[Improved QOL in a case of remnant gastric cancer with common bile duct obstruction treated with weekly paclitaxel therapy and cholecystojejunostomy].

We report a patient with unresectable remnant gastric cancer with common bile duct stricture, whose quality of life(QOL) was improved by switching to cholecystojejunostomy from percutaneous transhepatic gallbladder drainage(PTGBD). He was a 69-year-old man who underwent distal gastrectomy(Billroth I reconstruction)3 years previously, and he vomited many times due to cancer at the anastomosis. It could not be resected because of its involvement with the hepatoduodenal ligament, and therefore, gastrojejunostomy was performed. Four days later, abdominal pain occurred and gallbladder swelling was observed, resulting from common bile duct obstruction. PTGBD relieved the pain, and four courses of S-1/cisplatin (CDDP)treatment were performed. The bile duct stenosis was still so severe that the chemotherapy regimen was changed to weekly paclitaxel(PTX). The bile amount of PTGBD decreased after its four courses and the tube, which was a great burden for the patient, was removed. Because abdominal pain recurred in 2 weeks, the tube needed to be reinserted. An endoscopic stent was not inserted successfully. We performed cholecystojejunostomy and he was finally free from the PTGBD tube. The spread of cancer to the cystic duct was controlled by continuing the PTX for more than 20 courses. Thus, this case highlights PTX's contribution toward improving the patient's QOL.

[Three cases effectively treated with S-1 therapy for liver metastasis of breast cancer in long term].

We experienced 3 cases of anti-cancer drug-resistant recurrent breast cancer with liver metastasis showing significant improvement by S-1. Almost all patients maintained the full dose through the whole course of treatment, and the drug showed good tolerability. Furthermore, long-term therapeutic efficacy(more than 2 years)and QOL have been maintained for all patients. We concluded that S-1 is not only effective as a therapeutic agent, but is safe and maintains QOL.

[A case of advanced ascending colon cancer, curatively resected after complete response in left supraclavicular and paraaortic lymph nodes and liver metastases to FOLFOX4 therapy].

We report a resected case of ascending colon cancer with left supraclavicular and paraaortic lymph nodes and liver metastases which completely responded in terms of metastases but not the primary tumor to FOLFOX4 therapy. A 62-year-old woman with epigastric discomfort was initially diagnosed as malignant lymphoma by FDG-PET with abnormal accumulation at left supraclavicular and paraaortic lesions. Pathological examination of the supraclavicular lymph nodes showed undifferentiated adenocarcinoma, and ascending colon cancer was detected by colonoscopy which was a mixture of various types of differentiation. FOLFOX4 therapy was effective for metastatic lesions but colon tumor did not regress and was accompanied by abdominal pain. Macroscopically, a curative right hemicolectomy was performed, and microscopic examination revealed that the tumor had become a mass of undifferentiated cancer cells. Thus, the present case demonstrates the dedifferentiation of colon cancer during chemotherapy.

Adenovirus vectors with chimeric type 5 and 35 fiber proteins exhibit enhanced transfection of human pancreatic cancer cells.

Adenovirus (Ad) vectors are widely used for gene transfer. Efficient gene transfer into malignant cells is an important requirement for anticancer gene therapy, but transgene expression after transfer with adenoviral vectors varies among different cancer cell lines. Recently, Ad vectors containing chimeric type 5 and 35 fiber proteins have been developed. We evaluated the expression of coxsackie and adenovirus receptor (CAR), as well as integrins alphaV, beta3 and beta5, in seven human pancreatic cancer cell lines and assessed the relationship between expression of these molecules and Ad transfection efficiency. We compared the transfection efficiency of a conventional type 5 Ad vector (Ad5GFP) with that of an Ad vector containing chimeric type 5 and 35 fiber proteins (Ad5/35GFP), which expressed green fluorescent protein (GFP) driven by the cytomegalovirus promoter. There was strong CAR expression by AsPC-1, CFPAC-1 and PANC-1 cells, whereas the other cell lines showed weak expression. There was strong integrin beta3 expression by MIAPaCa-2, PANC-1 and Suit-2 cells, but expression by AsPC-1, BxPC-3, CFPAC-1 and HPAC cells was weak. Transfection efficiency of the vectors for human pancreatic cancer cell lines was not directly related to the CAR or integrin expression. However, transfection by Ad5/35GFP was significantly greater than by Ad5GFP at MOIs of 10 and 25 in all five human pancreatic cell lines. In conclusion, the Ad5/35GFP vector mediates more efficient gene transfer to human pancreatic cancer cells. These results may have implications for improving the efficiency of Ad-mediated gene transfer and developing adenoviral vectors.

Synthesis of 2,5,8,11,14,17-hexafluoro-hexa-peri- hexabenzocoronene for n-type organic field-effect transistors.

A fluorine-substituted hexa-peri-hexabenzocoronene was synthesized as a thermostable active material for n-type semiconductors. The LUMO and HOMO energy levels, estimated by UV-vis and photoelectron spectroscopy, were lower by 0.5 eV than those of hexa-peri-hexabenzocoronene. A field-effect transistor fabricated by vacuum sublimation showed n-type performance with a field-effect mobility of 1.6 x 10(-2) cm(2)/Vs and an on/off ratio of 10(4). The electron-withdrawing effect of the fluorine substituents changed the polarity from p-type to n-type.

Bcl-XL antisense oligonucleotides coupled with antennapedia enhances radiation-induced apoptosis in pancreatic cancer.

BACKGROUND: Pancreatic cancer is highly resistant to radiation and chemotherapy, and its resistance reflects the enhancement of apoptosis inhibitory genes, including Bcl-2 family. Antennapedia (pAnt) is capable of almost 100% internalization into cells through the lipid bilayer without any cytotoxic effect. The aim of this study was to examine the effects of the Bcl-XL antisense oligonucleotide for radiosensitivity of in vitro and in vivo pancreatic cancer using oligonucleotide conjugated with antennapedia. METHODS: In in vitro experiments, expression of Bcl-XL protein was examined in 5 pancreatic cancer cell lines. In AsPC-1 cells, internalization of the oligonucleotide was confirmed, and the effects of antennapedia-antisense (pAnt-AS) or antennapedia-scramble (pAnt-Scr) on Bcl-XL protein expression were examined. Cells were treated with pAnt-AS, pAnt-Scr or phosphorothioate antisense (S-AS) for 3 days, then the effects of irradiation on the cell survival, caspase-3 activity, and apoptotic index were evaluated. In AsPC-1 xenograft mice, pAnt-AS, pAnt-Scr, or S-AS was injected, and 5 or 10 Gy irradiation was added. Bcl-Xl protein expression was measured before irradiation. Apoptosis was evaluated at 48 hours after irradiation. On the 14th day after 10-Gy irradiation, tumor wet weight was measured, and tumor growth was estimated over 5 weeks. RESULTS: In in vitro experiments, all pancreatic cancer cell lines expressed Bcl-XL protein. pAnt-AS was internalized into AsPC-1 cells within 2 hours. pAnt-AS at 10 mumol/L reduced more than 90% of the Bcl-XL protein in AsPC-1 cells, whereas pAnt-Scr or S-AS treatment at the same concentration reduced as much as 10% of the Bcl-XL protein. Treatment with pAnt-AS followed by irradiation significantly reduced cell viability when compared with that of pAnt-Scr or S-AS. Caspase-3 activity was significantly upregulated in the pAnt-AS-treated group (P = .033). The rate of nuclear fragmentation was significantly higher in the pAnt-AS group (P = .013). In in vivo experiments, Bcl-XL protein was reduced about 40% in the pAnt-AS-treated mice. Tumor doubling time of the pAnt-AS-treated mice was elongated by 10-Gy irradiation. The tumor wet weight of mice treated with pAnt-AS and 10-Gy irradiation was significantly reduced when compared with mice treated with pAnt-Scr and 10-Gy irradiation (P = .046). The apoptosis index at 48 hours after irradiation was significantly increased in pAnt-AS-treated mice (P < .01). CONCLUSIONS: The results suggest that, when coupled with antennapedia, the antisense oligonucleotide against Bcl-XL could be a good therapeutic tool for radiosensitization of pancreatic cancer.

Development of a 111In-labeled peptide derivative targeting a chemokine receptor, CXCR4, for imaging tumors.

The chemokine receptor CXCR4 is highly expressed in tumor cells and plays an important role in tumor metastasis. The aim of this study was to develop a radiopharmaceutical for the imaging of CXCR4-expressing tumors in vivo. Based on structure-activity relationships, we designed a 14-residue peptidic CXCR4 inhibitor, Ac-TZ14011, as a precursor for radiolabeled peptides. For 111In-labeling, diethylenetriaminepentaacetic acid (DTPA) was attached to the side chain of d-Lys(8) which is distant from the residues indispensable for the antagonistic activity. In-DTPA-Ac-TZ14011 inhibited the binding of a natural ligand, stromal cell-derived factor-1alpha, to CXCR4 in a concentration-dependent manner with an IC50 of 7.9 nM (Ac-TZ14011: 1.2 nM). In biodistribution experiments, more 111In-DTPA-Ac-TZ14011 accumulated in the CXCR4-expressing tumor than in blood or muscle. Furthermore, the tumor-to-blood and tumor-to-muscle ratios were significantly reduced by coinjection of Ac-TZ14011, indicating a CXCR4-mediated accumulation in tumor. These findings suggested that 111In-DTPA-Ac-TZ14011 would be a potential agent for the imaging of CXCR4 expression in metastatic tumors in vivo.

All-trans retinoic acid induces differentiation of ducts and endocrine cells by mesenchymal/epithelial interactions in embryonic pancreas.

Retinoids during the embryonic period act as a mesenchymal inducer in many organs, including kidney, lung, central nervous system, and gut. Retinoic acid (RA) demonstrates insulinotropic effects in adult pancreas, but only a limited study has elucidated its role in pancreatic organogenesis. In this study, we have analyzed the existence of RA-signaling machinery in embryonic pancreas and evaluated its role using in vitro tissue culture experiments. Here we show the presence of endogenous retinaldehyde dehydrogenase 2 (RALDH2), the most effective RA-synthesizing enzyme, RA-binding proteins, and RA receptors (RARs) in embryonic pancreatic tissue. RALDH2 is expressed exclusively in the mesenchyme. Exogenously added all-trans-retinoic acid (atRA) in tissue culture experiments stimulated differentiation of endocrine and duct cells and promoted apoptotic cell death of acinar tissue. Furthermore, we demonstrate that atRA upregulates the PDX-1 expression. Taken together, our data suggest that atRA-mediated mesenchymal/epithelial interactions play an important role in determining the cell fate of epithelial cells via regulation of the PDX-1 gene, leading to the proper formation of the endocrine versus exocrine component during pancreatic organogenesis.

Expression and prognostic value of tuberous sclerosis complex 2 gene product tuberin in human pancreatic cancer.

BACKGROUND: Tuberous sclerosis complex (TSC) is an autosomal dominant disorder caused by mutation of either of 2 tumor suppressor genes, TSC1 or TSC2, which encode hamartin and tuberin, respectively. Several studies have shown that tuberin functions independently of hamartin and inhibits signaling pathways via the mammalian target of rapamycin, a critical regulator of cell proliferation. Recent studies have revealed that the signaling pathways regulating the mammalian target of rapamycin such as Akt and S6K1 are frequently activated in pancreatic cancer. We hypothesized that tuberin might be involved in the proliferation and survival of pancreatic cancer cells. METHODS: We immunohistochemically examined the expression of tuberin in 42 pancreatic cancerous and noncancerous pancreatic tissue specimens using an antituberin antibody. The correlations between tuberin expression and various clinicopathologic features, including survival, were evaluated. Reverse transcriptase-polymerase chain reaction was performed to evaluate the level of tuberin expression in paired samples of pancreatic cancer and noncancerous tissue. RESULTS: Twenty-four of the 42 pancreatic cancer samples (57%) were negative for tuberin expression. The patients with tuberin-negative tumors had a significantly higher incidence of pT3 or pT4 disease (primary tumor extent by the TNM classification) than those with tuberin-positive tumors (P = .024). Female patients had a significantly higher incidence of tuberin-positive tumors than male patients (P = .014). The survival rate of the tuberin-positive group tended to be better than that of the tuberin-negative group, but there was no significant difference (P = .4). Expression of TSC2 in cancer tissue was lower than in the corresponding noncancerous tissue for 7 of the 9 samples examined. CONCLUSIONS: This study demonstrates that reduced expression of tuberin might be involved in the progression of pancreatic cancer. Accordingly, tuberin may provide a new therapeutic target in patients with this type of cancer.

Regulation of the resistance to TRAIL-induced apoptosis as a new strategy for pancreatic cancer.

BACKGROUND: Tumor necrosis factor-related, apoptosis-inducing ligand (TRAIL) is a potent inducer of apoptosis in a wide variety of tumor cells, but it does not cause toxicity in the majority of normal cells. Therefore, TRAIL could become a suitable agent for anticancer therapies. However, a number of tumor cell lines are known to be resistant to TRAIL-induced apoptosis. The purpose of this study was to determine the mechanisms of resistance to TRAIL in pancreatic cancer cells. METHODS: In human pancreatic cancer cell lines, the sensitivity to TRAIL-induced apoptosis was tested. The expression of TRAIL receptors (DR4, DR5, DcR1, and DcR2) and the expression of death signal-transducing proteins were investigated. In the TRAIL-resistant pancreatic cancer cells, effects of cycloheximide, a protein synthesis inhibitor, on death signal-transducing proteins were tested. Finally, the effects of the combined treatment with cycloheximide and TRAIL on the induction of apoptosis and on the expression of death signal-transducing proteins were examined. RESULTS: Pancreatic cancer cells responded to TRAIL in a different way. Resistant cell lines, AsPC-1, Suit-2, and CFPAC-1, expressed higher levels of FLIP-S protein, one of the splice variants of FLIP. Cycloheximide reduced the expression of FLIP in the resistant cells. Combined treatment with cycloheximide and TRAIL induced cleaved forms of caspases and simultaneously restored the sensitivity to TRAIL-induced apoptosis in the resistant cells. CONCLUSIONS: Pancreatic cancer cells are resistant to TRAIL-induced apoptosis via strong expression of the anti-apoptotic protein FLIP-S. Suppression of FLIP-S by cycloheximide restored sensitivity to TRAIL-induced apoptosis in resistant cancer cells. These findings may provide useful information for the development of TRAIL-based therapeutic strategies aimed at restoring the functionality of apoptotic pathways in pancreatic cancer cells.

Pancreatic epithelial cells can be converted into insulin-producing cells by GLP-1 in conjunction with virus-mediated gene transfer of pdx-1.

BACKGROUND: Glucagonlike peptide-1 (GLP-1) stimulates insulin secretion and proliferation by islet cells in vitro and in vivo, associated with an activation of pancreatic duodenal homeobox gene-1 (pdx-1) function. The effect of GLP-1 on the conditionally immortalized pancreatic epithelial cells (IMPE cells) is not clear when they are treated in conjunction with the adenovirus-mediated gene transfer of pdx-1. METHODS: IMPE cells were established from the pancreas of H-2K(b)-tsA58 transgenic mice. IMPE cells were maintained at 33 degrees C with 10 U/mL interferon (IFN)-gamma and the experiments were performed at 39 degrees C without IFN-gamma. IMPE cells were infected with 20 multiplicities of Ad-pdx-1 or control Ad-lacZ at 39 degrees C without IFN-gamma and were incubated with various concentrations of GLP-1. After 48 hours, immunofluorescence and reverse transcriptase-polymerase chain reaction for insulin and pdx-1 expression were examined. Immunoreactive insulin in the cell lysate and supernatant was also analyzed. The glucose concentration in the culture medium was changed to test the insulin secretory responsiveness of the IMPE cells. RESULTS: The treatment with GLP-1 in conjunction with Ad-pdx-1 induced insulin production by IMPE cells, but the treatment with either GLP-1 or Ad-pdx-1 alone failed to induce insulin production. Insulin production and secretion were increased by GLP-1 and by glucose in a dose-dependent manner. In addition, the insulin-producing IMPE cells acquired a rapid insulin secretory responsiveness to the changes of extracellular glucose concentration. CONCLUSIONS: GLP-1 and pdx-1 work together to induce insulin-producing cells from IMPE cells, which bear unique characteristics of pancreatic ductal cells. The results suggest that GLP-1 may be another important determiner of pancreatic endocrine differentiation as is pdx-1.

Downregulation of survivin by siRNA diminishes radioresistance of pancreatic cancer cells.

BACKGROUND: Survivin is a member of the inhibitor of apoptosis protein family, which inhibits apoptosis and regulates cell division. Survivin is expressed by the majority of human cancers, including pancreatic adenocarcinoma. We have reported that its expression is correlated with shorter survival of pancreatic cancer patients, so regulation of this molecule could be a new strategy for fighting pancreatic cancer. METHODS: In 3 pancreatic cancer cell lines (AsPC-1, SUIT-2, and Panc-1), survivin promoter activity was determined by the luciferase reporter assay, and survivin messenger RNA (mRNA) expression was examined by quantitative reverse transcriptase-polymerase chain reaction. The dose-dependent cytotoxity of radiation was also assessed, while caspase-3 activity and induction of DNA fragmentation were evaluated. Furthermore, the effect of silencing or nonsilencing short interfering RNA (siRNA) expression plasmids directed against the survivin gene on AsPC-1 cells, the most radioresistant cell line, was evaluated. RESULTS: Pancreatic cancer cell lines expressed varying levels of survivin mRNA in association with transcriptional activity of the survivin promoter. Both survivin promoter activity and mRNA expression were correlated with tumor cell radiosensitivity. Radiation significantly increased survivin promoter activity and survivin mRNA expression in all cell lines. Radiation induced a significant increase in caspase-3 activity and DNA fragmentation in AsPC-1 cells. After silencing siRNA treatment of AsPC-1 cells (AS-S cells), there was a significant decrease in survivin mRNA expression and increase in caspase-3 activity, compared with the effect of nonsilencing scramble siRNA on AsPC-1 cells (AS-NS cells). AS-S cells were more radiosensitive than AS-NS cells. Radiation induced higher caspase-3 activity and more DNA fragmentation in AS-S cells, compared with AS-NS cells. CONCLUSIONS: Survivin may play an important role as 1 of the radioresistance factors. Downregulation of survivin by siRNA can diminish the radioresistance of pancreatic cancer cells, so combined therapy with survivin inhibition and radiation may be useful for the treatment of pancreatic cancer.

RECK expression in pancreatic cancer: its correlation with lower invasiveness and better prognosis.

BACKGROUND: The reversion-inducing cysteine-rich protein with Kazal motifs (RECK) gene was initially isolated as a transformation suppressor gene. The RECK gene is expressed widely in normal organs but is undetectable in many tumor-derived cell lines. When artificially expressed in such cell lines, RECK negatively regulates at least matrix metalloprotease (MMP)-9, MMP-2, and MT1-MMP activation and suppresses the invasive and metastatic potentials of these cells. Clinical relevance of these observations, however, is yet to be established. The aim of this study was to examine RECK expression in pancreatic cancer, where intensive invasiveness and metastasis are frequently observed, and investigate its clinical significance. We also analyzed the correlation between RECK expression and MMP activation. METHODS: (a) RECK expression in surgically resected tissue samples of invasive ductal carcinomas of the pancreas (n = 50) was examined immunohistochemically, and its correlation with clinicopathological factors was analyzed; and (b) gelatin zymography was used for the detection of latent and activated forms of MMP-2 and MMP-9 in some of the tissue samples (n = 33). The gelatinase activity was quantified by densitometory, and the ratio of intensity of the active MMP-2 band to the total intensity of the pro- and active MMP-2 bands was evaluated as an indicator of MMP-2 activation. The MMP-9 activation was also studied. RESULTS: Among the 50 ductal carcinoma samples, 26 (52%) were stained positive for RECK. In the normal pancreas, both acinar and beta cells were stained positive, but ductal cells did not. Tumors with positive RECK staining were significantly less invasive as compared with RECK-negative tumors (P = 0.0438). Importantly, patients who had tumors with high RECK expression showed significantly better prognosis than those who had RECK-negative tumors (P = 0.0463, by Log-rank test). Zymographic analysis indicated significant inverse correlation between the level of RECK expression and extent of MMP-2 activation (P = 0.0374). CONCLUSIONS: Our findings support the hypothesis that the RECK protein has negative effects on the invasiveness of pancreatic cancer by inhibiting MMP-2 activation and suggest the potential value of RECK as a prognostic molecular marker for pancreatic cancer.

N-cadherin expression and epithelial-mesenchymal transition in pancreatic carcinoma.

PURPOSE: Loss of intercellular adhesion and increased cell motility promote tumor cell invasion. In the present study, E- and N-cadherin, members of the classical cadherin family, are investigated as inducers of epithelial-to-mesenchymal transition (EMT) that is thought to play a fundamental role during the early steps of invasion and metastasis of carcinomas. Cell growth factors are known to regulate cell adhesion molecules. The purpose of the study presented here was to investigate whether a gain in N-cadherin in pancreatic cancer is involved in the process of metastasis via EMT and whether its expression is affected by growth factors. EXPERIMENTAL DESIGN: We immunohistochemically examined the expression of N- and E-cadherins and vimentin, a mesenchymal marker, in pancreatic primary and metastatic tumors. Correlations among the expressions of N-cadherin, transforming growth factor (TGF)beta, and fibroblast growth factor 2 was evaluated in both tumors, and the induction of cadherin and vimentin by growth factors was examined in cultured cell lines. RESULTS: N-cadherin expression was observed in 13 of 30 primary tumors and in 8 of 15 metastatic tumors. N-cadherin expression correlated with neural invasion (P = 0.008), histological type (P = 0.043), fibroblast growth factor expression in primary tumors (P = 0.007), and TGF expression (P = 0.004) and vimentin (P = 0.01) in metastatic tumors. Vimentin, a mesenchymal marker, was observed in a few cancer cells of primary tumor but was substantially expressed in liver metastasis. TGF stimulated N-cadherin and vimentin protein expression and decreased E-cadherin expression of Panc-1 cells with morphological change. CONCLUSION: This study provided the morphological evidence of EMT in pancreatic carcinoma and revealed that overexpression of N-cadherin is involved in EMT and is affected by growth factors.

Effects of protein and peptide addition on lipid oxidation in powder model system.

The effect of protein and peptide addition on the oxidation of eicosapentaenoic acid ethyl ester (EPE) encapsulated by maltodextrin (MD) was investigated. The encapsulated lipid (powder lipid) was prepared in two steps, i.e., mixing of EPE with MD solutions (+/- protein and peptides) to produce emulsions and freeze-drying of the resultant emulsions. EPE oxidation in MD powder progressed more rapidly in the humid state [relative humidity (RH) = 70%] than in the dry state (RH = 10%). The addition of soy protein, soy peptide, and gelatin peptides improved the oxidation stability of EPE encapsulated by MD, and the inhibition of lipid oxidation by the protein and the peptides was more dramatic in the humid state. Especially, the oxidation of EPE was almost perfectly suppressed when the lipid was encapsulated with MD + soy peptide during storage in the humid state for 7 days. Several physical properties such as the lipid particle size of the emulsions, the fraction of nonencapsulated lipids, scanning electron microscopy images of powder lipids, and the mobility of the MD matrix were investigated to find the modification of encapsulation behavior by the addition of the protein and peptides, but no significant change was observed. On the other hand, the protein and peptides exhibited a strong radical scavenging activity in the powder systems as well as in the solution systems. These results suggest that a chemical mechanism such as radical scavenging ability plays an important role in the suppression of EPE oxidation in MD powder by soy proteins, soy peptides, and gelatin peptides.

CXCR4 antagonist inhibits stromal cell-derived factor 1-induced migration and invasion of human pancreatic cancer.

The stromal cell-derived factor-1 (SDF-1)/CXCR4 system is implicated in various instances of cell migration in mammals, including the migration of lymphocytes and the formation of metastases. We have recently synthesized a potent novel CXCR4 antagonist, TN14003. The purpose of this study was to investigate the role of SDF-1/CXCR4 axis in the pancreatic cancer metastasis via cell migration and invasion, and the inhibitory effect of TN14003 on pancreatic cancer cell metastasis. The expression of CXCR4 was detected in six pancreatic cancer cell lines by Western blotting and immunocytochemistry. In migration and invasion assays, SDF-1 stimulated both migration and invasion of cancer cells in a dose-dependent manner. The maximal effect of SDF-1 was observed at 100 ng/ml. SDF-1-induced migration and invasion of cancer cells were completely blocked by 100 nM TN14003. The stimulatory effect of SDF-1 on cancer migration and the inhibitory effect of TN14003 were mediated via the alteration in phosphorylation of mitogen-activated protein kinases. Treatment of cancer cells with 100 ng/ml SDF-1 resulted in a significant increase of actin polymerization, which was reduced by 100 nM TN14003. SDF-1 enhanced cancer cell adhesion to laminin, which was not reversed by TN14003. Taken together, SDF-1/CXCR4 axis is involved in pancreatic cancer metastasis through migration and invasion. The small molecule antagonists against CXCR4 such as TN14003 might be an effective anti-metastatic agent for pancreatic cancer.

Chronic exposure of transforming growth factor beta 1 confers a more aggressive tumor phenotype through downregulation of p21(WAF1/CIP1) in conditionally immortalized pancreatic epithelial cells.

BACKGROUND: Recent studies have demonstrated that transforming growth factor beta 1 (TGF-beta1) expression is markedly enhanced in invasive ductal pancreatic adenocarcinomas, although the precise role of TGF-beta1 in pancreatic carcinogenesis remains unclear. We analyzed TGF-beta1 expression in pancreatic intraepithelial neoplasias (PanINs) and the effects of chronic TGF-beta1 exposure on conditionally immortalized pancreatic epithelial (IMPE) cells. METHODS: Sixty-one PanIN lesions were immunohistochemically stained with a polyclonal rabbit antibody against human TGF-beta1. Growth-inhibitory effects of short-term exposure to TGF-beta1 were examined in IMPE cells. IMPE cells resistant to TGF-beta1 (IMPE-Tr cells) were generated by continuous exposure to 1 ng/mL of TGF-beta1 for more than 50 days. Phenotypic alterations of IMPE-Tr cells were examined by soft agar and Matrigel assay and Western blot analysis. IMPE and IMPE-Tr cells were injected subcutaneously into nude mice for an in vivo tumorigenicity assay. RESULTS: Forty-six percent of PanINs (28/61) were positive for TGF-beta1 expression, whereas all the epithelia of normal pancreatic ducts were negative. TGF-beta1 treatment showed the marked growth-inhibitory effects (>75%) in IMPE cells, whereas its effects were not observed in IMPE-Tr cells. IMPE-Tr cells were more spindle shaped compared with IMPE cells. In soft agar and Matrigel, formations of many colonies were observed in IMPE-Tr cells, but not in IMPE cells. Interestingly, the expression of p21(WAF1/CIP1) was induced by short-term exposure to TGF-beta1 in IMPE cells, whereas the induction was decreased in IMPE-Tr cells. All of the IMPE-Tr cell-injected mice (5/5) had subcutaneous tumors, although no tumor was found in the IMPE cell-injected mice. CONCLUSIONS: TGF-beta1 expression in PanINs and neoplastic transformation of IMPE cells by long-term exposure to TGF-beta1 suggest that TGF-beta1 may act as a tumor promoter in the early stage of pancreatic carcinogenesis.

Survivin expression is a prognostic marker in pancreatic cancer patients.

BACKGROUND: In this study, we assessed survivin expression in pancreatic cancer specimens from patients who underwent either pancreatic resection alone or pancreatic resection plus postoperative radiation therapy (PORT) to evaluate whether survivin expression is predictive of sensitivity to PORT and outcome in pancreatic cancer patients. METHODS: Fifty-two patients who underwent pancreatic resection for ductal adenocarcinomas were included in this study. Forty-seven pancreatic ductal adenocarcinoma and 5 normal pancreatic tissues were evaluated for survivin expression by immunohistochemistry. Then the relationship between survivin expression and clinicopathologic data were analyzed. RESULTS: Sixty-eight percent (32/47) of pancreatic cancer tissues were positive for survivin expression; 32% (15/47) were negative. Normal pancreatic exocrine tissues were negative for survivin expression (0/5). Survival of the patients with positive survivin was significantly shorter than those with negative survivin (P = .02). Survivin was an independent variable that correlated with overall survival (P = .01). There was no difference in survival time between patients with and without PORT. Likely, PORT showed no impact on survival time in survivin-positive patients (P = .12) as well as in survivin-negative patients (P = .95). CONCLUSIONS: The results suggest that survivin expression in pancreatic cancer tissues could be a useful prognostic marker in pancreatic cancer patients.

Hepatic regeneration and enforced PDX-1 expression accelerate transdifferentiation in liver.

BACKGROUND: Pancreatic duodenal homeobox gene-1 (PDX-1) has a dual task as a key regulator in pancreatic organogenesis and in functional maintenance of beta cells in adults. Recent studies have shown a close lineage relationship between the liver and the pancreas. In this study, we analyzed the plasticity of the liver by enforced expression of PDX-1 in streptozotocin (STZ)-treated mice under the condition of hepatic regeneration. METHODS: Replication-deficient adenoviruses were constructed by the cosmid-adenoviral DNA terminal protein complex method. Mice were treated with STZ (200 mg/kg ip), and a 40% partial hepatectomy was performed at day 0. After 24 hours, Ad-pdx-1 or Ad-lacZ 2.0 x 10(9) PFU/body was injected via the tail vain into nontreated (control), STZ-treated, or STZ plus partial hepatectomy (Hx)-treated ICR mice. After 7 and 14 days, expression of PDX-1 and islet hormones was examined by immunohistologic and reverse transcription-polymerase chain reaction analysis. Blood glucose concentrations were measured every 2 days. Immunoreactive insulin (IRI) of serum and liver extract was measured by ELISA. RESULTS: Most hepatocytes of Ad-pdx-1-infected mice were positive for PDX-1 expression by immunohistochemistry. In nontreated mice, very few cells expressed insulin and other hormones. In contrast, insulin and somatostatin were expressed in STZ-treated mice, and more cells were expressed in STZ plus Hx-treated mice. In addition, other beta-cell markers like GLUT2 and glucokinase were observed. Hyperglycemia was improved in STZ-treated mice and STZ plus Hx-treated mice. IRI of serum and liver extract was increased in STZ-treated mice and STZ plus Hx-treated mice. The insulin positive area of the liver in STZ plus Hx-treated mice was larger than that in nontreated and STZ-treated mice. CONCLUSIONS: Ectopic PDX-1 expression alone may be insufficient to induce insulin-producing cells in the liver. STZ-induced hyperglycemia plus partial hepatectomy that leads to diabetic state and hepatic regeneration may stimulate the transdifferentiation of liver cells into insulin-producing cells.