Hedgehog Promotes Neovascularization in Pancreatic Cancers by Regulating Ang-1 and IGF-1 Expression in Bone-Marrow Derived Pro-Angiogenic Cells

http://creativecommons.org/licenses/by/2.0/ PublisherBackground: The hedgehog (Hh) pathway has been implicated in the pathogenesis of cancer including pancreatic ductal adenocarcinoma (PDAC). Recent studies have suggested that the oncogenic function of Hh in PDAC involves signaling in the stromal cells rather than cell autonomous effects on the tumor cells. However, the origin and nature of the stromal cell type(s) that are responsive to Hh signaling remained unknown. Since Hh signaling plays a crucial role during embryonic and postnatal vasculogenesis, we speculated that Hh ligand may act on tumor vasculature specifically focusing on bone marrow (BM)-derived cells. Methodology/Principal Findings: Cyclopamine was utilized to inhibit the Hh pathway in human PDAC cell lines and their xenografts. BM transplants, co-culture systems of tumor cells and BM-derived pro-angiogenic cells (BMPCs) were employed to assess the role of tumor-derived Hh in regulating the BM compartment and the contribution of BM-derived cells to angiogenesis in PDAC. Cyclopamine administration attenuated Hh signaling in the stroma rather than in the cancer cells as reflected by decreased expression of full length Gli2 protein and Gli1 mRNA specifically in the compartment. Cyclopamine inhibited the growth of PDAC xenografts in association with regression of the tumor vasculature and reduced homing of BM-derived cells to the tumor. Host-derived Ang-1 and IGF-1 mRNA levels were downregulated by cyclopamine in the tumor xenografts. In vitro co-culture and matrigel plug assays demonstrated that PDAC cell-derived Shh induced Ang-1 and IGF-1 production in BMPCs, resulting in their enhanced migration and capillary morphogenesis activity. Conclusions/Significance: We identified the BMPCs as alternative stromal targets of Hh-ligand in PDAC suggesting that the tumor vasculature is an attractive therapeutic target of Hh blockade. Our data is consistent with the emerging concept that BM-derived cells make important contributions to epithelial tumorigenesis

Hematogenous Gastric Metastasis of Pancreatic Cancer

While the gastric involvement of pancreatic cancer is occasionally observed as the result of direct invasion, hematogenous gastric metastasis is rare. A 72-year-old Japanese male presented with general fatigue, pollakiuria, and thirst. Computed tomography revealed a 4.6-cm solid mass in the pancreatic tail and a 4.2-cm multilocular cystic mass in the pancreatic head with multiple liver and lymphatic metastasis. Notably, two solid masses were detected in the gastric wall of the upper body and the antrum; both were separated from the primary pancreatic cancer and seemed to be located in the submucosal layer. Esophagogastroduodenoscopy revealed a submucosal tumor with a normal mucosa in the posterior wall of the upper body of the stomach, suggesting the gastric hematogenous metastasis of pancreatic cancer. The suspected diagnosis was unresectable pancreatic cancer with multiple metastases that was concomitant with the intraductal papillary mucinous neoplasm of the pancreas

低酸素環境下に置かれるがん細胞の再酸素化による増殖能・浸潤能の変化

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Pancreatic Ductal Adenocarcinomas in Long-Term Follow-Up Patients With Branch Duct Intraductal Papillary Mucinous Neoplasms

http://journals.lww.com/pancreasjournal/pages/default.aspxObjective: Although branch duct intraductal papillary mucinous neoplasms (BD-IPMNs) are slow-growing tumors with a favorable prognosis, the synchronous occurrence of pancreatic ductal adenocarcinomas (PDAs) in patients with BD-IPMNs has been reported. This study was aimed to elucidate the development of PDAs in long-term follow-up patients with BD-IPMNs. Methods: We investigated 89 BD-IPMN patients who had no mural nodules and followed them up conservatively at least 2 years (median follow-up, 64 months; range, 25-158 months). All subjects underwent examinations by imaging modalities including endoscopic retrograde pancreatography. We calculated the standardized incidence ratio (SIR) from the vital statistics compiled by the Ministry of Health, Labor, and Welfare of Japan. Results: Among the 89 patients, 4 cases of PDAs distant from BD-IPMN were observed in 552 patient-years of follow-up (7.2 per 1000 patient-years). The expected number was 0.25, and the SIR of PDAs was 15.8 (95% confidence interval [CI], 4.3-40.4; P = 0.00014). Subgroup analyses showed that the incidence of PDAs was significantly increased in patients 70 years or older (SIR 16.7; 95% CI, 3.4-48.7; P = 0.0008) and in women (SIR 22.5; 95% CI, 2.7-81.1; P = 0.0037). Conclusions: Patients with BD-IPMNs are at a high risk for PDAs. During the follow-up, careful examination is required to detect the development of PDAs in patients with BD-IPMNs

Localization of the Most Severely Dysplastic/Invasive Lesions and Mucin Phenotypes in Intraductal Papillary Mucinous Neoplasm of the Pancreas

This is a non-final version of an article published in final form in Karasaki, Hidenori ; Mizukami, Yusuke ; Tokusashi, Yoshihiko ; Koizumi, Kazuya ; Ishizaki, Akira ; Imai, Kouji ; Yoshikawa, Daitaro ; Kino, Shuichi ; Sasajima, Junpei ; Tanno, Satoshi ; Matsumoto, Kakuya ; Miyokawa, Naoyuki ; Kono, Toru ; Kohgo, Yutaka ; Furukawa, Hiroyuki, Pancreas, 40(4), 588-594.Objective: The aim of this study was to define the relevance of mural nodules (MNs) as a "direct" indicator of malignancy of intraductal papillary mucinous neoplasm (IPMN) of the pancreas. Methods: Thirty-nine surgically resected IPMNs excluding obviously invasive carcinomas were examined. The distribution of the most severely dysplastic lesions was mapped on specimens. Immunohistochemical analysis for MUC1 and MUC2 was performed on sections containing the histologically predominant lesions and the most severely dysplastic areas. Results: The presence of MNs correlated well with the histological grade of IPMN (P < 0.01); however, the most severely dysplastic lesions were associated with a flat/nonelevated area rather than MNs (78.9%). In the MUC1-positive subgroup, minimally invasive carcinoma was colocalized to MNs, whereas most severely dysplastic foci including minimally invasive carcinoma with components of mucinous and tubular adenocarcinoma were observed in the areas apart from MNs in the MUC2-positive and MUC1/2-negative subgroups, respectively. Conclusions: Although our data support the concept that MNs represent areas of higher-grade dysplasia within IPMN, development of invasive lesions from MNs may be limited to cases that are MUC1-positive. Careful attention should be paid to the emergence of invasive IPMN from flat foci in MUC2-positive and MUC1/2-negative cases