Pancreatic ductal adenocarcinoma (PDAC), one of the most lethal neoplasms, is characterized by an expanded stroma with marked fibrosis (desmoplasia). We previously generated pancreas epithelium-specific TGF-β receptor type II (Tgfbr2) knockout mice in the context of Kras activation (mice referred to herein as Kras+Tgfbr2 KO mice) and found that they developed aggressive PDAC that recapitulated the histological manifestations of the human disease. The mouse PDAC tissue showed strong expression of connective tissue growth factor (Ctgf), a profibrotic and tumor-promoting factor, especially in the tumor-stromal border area, suggesting an active tumor-stromal interaction. Here we show that the PDAC cells in Kras+Tgfbr2 KO mice secreted much higher levels of several Cxc chemokines compared with mouse pancreatic intraepithelial neoplasia cells, which are preinvasive. The Cxc chemokines induced Ctgf expression in the pancreatic stromal fibroblasts, not in the PDAC cells themselves. Subcutaneous grafting studies revealed that the fibroblasts enhanced growth of PDAC cell allografts, which was attenuated by Cxcr2 inhibition. Moreover, treating the Kras+Tgfbr2 KO mice with the CXCR2 inhibitor reduced tumor progression. The decreased tumor progression correlated with reduced Ctgf expression and angiogenesis and increased overall survival. Taken together, our data indicate that tumor-stromal interactions via a Cxcr2-dependent chemokine and Ctgf axis can regulate PDAC progression. Further, our results suggest that inhibiting tumor-stromal interactions might be a promising therapeutic strategy for PDAC. IntroductionPancreatic cancer is the fourth and fifth leading cause of cancer death in the United States and Japan, respectively (1, 2). It is one of the most lethal cancers, with 5-year survival rate of less than 5% that is partially attributed to the difficulty of early diagnosis. Moreover, even with a successful resection, 5-year survival is still less than 20%. The poor outcome after resection may be due to the frequent aggressive character of pancreatic tumor cells, which are often able to efficiently invade, disseminate, and metastasize (3, 4).The most common type of human pancreatic cancer is pancreatic ductal adenocarcinoma (PDAC). Previous studies have suggested a multistep progression model of PDAC that includes a preinvasive state termed pancreatic intraepithelial neoplasia (PanIN). PDAC is thought to result from progression of PanIN lesions through accumulation of specific genetic alterations (5). Activation of a point mutation of the KRAS proto-oncogene and inactivation of tumor suppressor genes, including P16 INK4A , P53, and SMAD4 (also known as deleted in pancreatic adenocarcinoma 4 [DPC4]), have been shown to increase in frequency with progression of the PanIN stages. Notably, at the invasive stage, the mutations and deletions

Objective It has been discussed whether IgG4-related disease (IgG4-RD), including autoimmune pancreatitis (AIP), is associated with malignancy; however, the issue has not been clarified. Methods We analyzed 113 patients with IgG4-RD in whom malignancy was not diagnosed at the time of IgG4-RD onset and the follow-up period was longer than six months. A total of 95 patients had AIP. The mean follow-up period was 73 months. The incidence of the observed malignancies was compared with the expected incidence in an age-and sex-matched general Japanese population based on the Vital Statistics of Japan. Results There were 15 malignancies (lung cancer in five patients, pancreatic cancer in two patients, gastric cancer in two patients, bile duct cancer in one patient, renal cancer in one patient, breast cancer in one patient, tongue cancer in one patient, malignant melanoma in one patient and acute myeloid leukemia in one patient) in 14 patients during the follow-up period. The calculated standardized incidence rate of the total malignancies was not significant, that is, 1.04 (95% CI 0.57-1.75). Conclusion The incidence of total malignancies in IgG4-RD patients is similar to that observed in the general population. At present, it is reasonable to conclude that IgG4-RD is not associated with an increased incidence of total malignancies.

The hedgehog and mitogen-activated protein kinase (MAPK) signaling pathways regulate growth in many tumors, suggesting cooperation between these two pathways in the regulation of cell proliferation. However, interactions between these pathways have not been extensively studied. We assessed cross-talk between hedgehog and MAPK signaling in the regulation of cell proliferation in gastric cancer. We showed that PTCH expression was significantly correlated with extracellular signal-regulated kinase (ERK) 1/2 phosphorylation (P = 0.016) as well as SHH expression (P = 0.034) in the 35 gastric cancers assessed by immunohistochemistry. Indeed, MAPK signaling increased the GLI transcriptional activity and induced the expression of hedgehog target genes in gastric cancer cells. The inductive effect of activated KRAS and mitogen-activated protein/extracellular signal-regulated kinase kinase (MEK) 1 was blocked by the suppressor of fused (SUFU), indicating that MAPK signaling regulates GLI activity via a SUFU-independent process. Moreover, the deletion of the NH2-terminal domain of GLI1 gene resulted in reduced response to MEK1 stimulation. Our results suggest that the KRAS-MEK-ERK cascade has a positive regulatory role in GLI transcriptional activity in gastric cancer.

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Modified LCD achieved a high technical success rate both in the initial stent-in-stent placement and in bilateral reinterventions in patients with malignant hilar biliary obstruction.