Yasuhisa Koyanagi

Potent Antitumor Activity of Interleukin-27

Although much promising data that interleukin (IL)-12 could be a powerful therapeutic agent against cancer were reported in animal models, its excessive toxicity has become a problem for its clinical application. IL-27 is a novel IL-12 family member that plays a role in the early regulation of T helper cell 1 initiation, including induction of T-bet and IL-12 receptor β2 expression. In the present study, we have evaluated the antitumor activity of IL-27 against a murine tumor model of colon carcinoma C26. C26 cells, which were transduced with the single-chain IL-27 cDNA and became secreting IL-27 (C26-IL-27), exhibited minimal tumor growth in vivo, and all of the mice inoculated with these cells survived healthily with complete tumor remission. Inoculation of mice with C26-IL-27 induced enhanced IFN-γ production and cytotoxic T-lymphocyte activity against C26 tumor in spleen cells. Recovered mice from the inoculation showed a tumor-specific protective immunity to the following challenge with parental C26 tumor. The antitumor activity of IL-27 was almost diminished in nude mice, and depletion of CD8+ T cells and neutralization of IFN-γ in immunocompetent mice reduced greatly the antitumor activity. Moreover, the antitumor activity was abolished in T-bet-deficient mice, whereas it was observed unexpectedly in mice deficient of signal transducer and activator of transcription (STAT) 4. These results suggest that IL-27 has potent abilities to induce tumor-specific antitumor activity and protective immunity and that the antitumor activity is mediated mainly through CD8+ T cells, IFN-γ, and T-bet but not through STAT4.

Direct measurement of the extravasation of polyethyleneglycol-coated liposomes into solid tumor tissue by in vivo fluorescence microscopy

Abstract The extravasation of liposomes of different sizes into solid tumors after i.v. injection was visualized by in vivo fluorescence microscopy in mouse neuroblastoma C-1300-bearing mice. Liposomes composed of distearoylphosphatidylcholine/cholesterol (1/1 molar ratio) and 6 mol% distearoylphosphatidylethanolamine derivative of polyethyleneglycol (PEG) were prepared. The PEG-coated liposomes were fluorescently labeled with 1,1′-dioctadecyl-3,3,3′,3′-tetramethylindocarbocyanine perchlorate (DiI) as a liposome marker or with doxorubicin (DXR) as an aqueous-phase marker. Liposomes with an average diameter of 100–200 nm showed the greatest tumor accumulation. With time after injection of DiI-labeled liposomes, the tumor interstitial fluorescence intensity increased. Most fluorescent spots were located outside and around the vessel wall, indicating extravasation of intact liposomes. The perivascular distribution was heterogeneous. We also obtained the same fluorescence localization pattern with DXR released from extravasated liposomes after injection of DXR-encapsulated liposomes. No fluorescence from extravasated liposomes was detected in normal s.c. tissue; the fluorescent spots were observed only in the vessel wall. Our results indicate that small-size long-circulating liposomes are able to traverse the endothelium of blood vessels in tumors and extravasate into interstitial spaces. Moreover, encapsulated drug was released from extravasated liposomes in the tumor.

Histologic features of venous invasion, expression of vascular endothelial growth factor and matrix metalloproteinase-2 and matrix metalloproteinase-9, and the relation with liver metastasis in pancreatic cancer.

Introduction Pancreatic cancer frequently is associated with venous invasion and hematogenous metastasis. Aims To determine morphologic features of invaded veins, intratumoral vascular composition, the correlation with liver metastasis, and expression of vascular endothelial growth factor (VEGF), matrix metalloproteinase (MMP)-2 and MMP-9, and the mechanism of development of hematogenous metastasis. Methodology We examined 32 patients with resected pancreatic cancer: 18 had postoperative liver metastasis, and 14 had no liver metastasis. Specimens were examined to determine the composition of veins and microvessels by staining of victoria-blue and CD34. We also investigated expression of VEGF, MMP-2, and MMP-9 by immunohistochemical staining. Results Venous invasion was detected in 31 of 32 patients. Invaded venous densities of middle- and large-sized veins were significantly higher in patients with liver metastasis than in those with nonliver metastasis, and they were related to MMP-2 and MMP-9 overexpression. Invaded veins with fragmentation of the lumen through cancer cells were considered to be an intravasation of cancer (destroyed type vein), and their numbers were significantly related to liver metastasis, and MMP-2 and MMP-9 overexpression. Conclusion In conclusion, almost all the patients with pancreatic cancer showed venous invasion, indicating that invasion into large veins and destroyed type veins could be a risk factor for liver metastasis and that increased expression MMP-2 and MMP-9 were related to such invasion.

Mammary ductoscopy for diagnosis and treatment of intraductal lesions of the breast

BackgroundMammary ductoscopy (mammoscopy) is an ideal diagnostic method for intraductal lesions. The usefulness of mammoscopy for intraductal lesions was evaluated.MethodsMammoscopy was performed in 315 cases with nipple discharge. The mammoscopic findings of 46 breast cancer cases (47 lesions) and 109 intraductal papilloma cases (119 lesions) were compared with pathological findings.ResultsCarcinoma was recognized by mammoscopy in 38 of 47 lesions (80.9%). Intraductal masses were detected by mammoscopy in 115 of 119 intraductal papilloma lesions. The shape of the mass was classified as hemispheric, papillary, or flat protrusion. The hemispheric and papillary shapes were most common in cases of intraductal papilloma and the flat protrusion type was most common in cases of carcinoma. The amount of material collected by intraductal biopsy under mammoscopic observation was smaller in carcinoma than in intraductal papilloma because the carcinoma lesions were usually located in peripheral ductlobular units and had weak tissue cohesion compared with that of intraductal papilloma. Of 133 intraductal biopsies performed for 69 intraductal papillomas, 17 biopsies yielded material insufficient for diagnosis in. The effectiveness of treatment by intraductal biopsy was recognized in 38 of 46 intraductal papillomas in which clinical follow-up continued for more than two years (82.6%). The therapeutic results of biopsy were poor in cases of multiple intraductal masses in multiple duct-lobular units.ConclusionsMammoscopy contributes not only the diagnosis in cases of nipple discharge, but is also of benefit in the treatment of intraductal papilloma.

Nuclear accumulation of beta-catenin in intestinal-type gastric carcinoma: correlation with early tumor invasion

Abstract. Mutation of the adenomatous polyposis coli gene, which is known to be an early event in the carcinogenesis of intestinal-type gastric carcinoma, leads to accumulation of beta-catenin. In addition, beta-catenin has been found to activate down stream signaling molecules in the wingless/Wnt pathway. In this study, the clinical significance of nuclear accumulation of beta-catenin was evaluated in gastric carcinoma. Immunohistochemical staining showed nuclear localization in 16 (12%) of 139 (94 intestinal-type and 45 diffuse-type) gastric carcinomas, and all 16 lesions with nuclear staining were intestinal-type adenocarcinomas. Of the 16 cases, 15 were in the early clinical stage. In the remaining case, the lesion had invaded the subserosal layer and showed strong nuclear staining at the invasive front. In 14 of the 16 cases with nuclear localization, there were no abnormal mobility shifts detected using polymerase chain reaction-single strand conformational polymorphism analysis. This was confirmed using direct sequencing analysis, which revealed the wild-type sequence in the 12 cases tested. Nuclear accumulation of beta-catenin did not correlate with lymph node metastasis or 5-year survival. These findings suggest that high intranuclear levels of beta-catenin protein play an important role in early tumor growth and may function in initiation of invasive processes in intestinal-type gastric carcinoma.

Gallbladder Metastasis of Renal Cell Carcinoma: Report of Two Cases

Abstract We report two extremely rare cases of metastasis to the gallbladder from renal cell carcinoma. In both men, aged 63 and 80 years, a pedunculated polypoid gallbladder tumor was incidentally found 27 and 8 years after surgery for renal cell carcinoma, respectively. The tumors showed hypervascularity on diagnostic imaging. A histopathological examination showed no tumor cells in the gallbladder mucosa, but clear cell carcinoma was predominantly observed below the mucosal layer. Furthermore, based on various specific and immunohistochemical studies as well as the electron-microscopic findings, the patients were pathologically diagnosed to have gallbladder metastasis of renal cell carcinoma.

Pancreatic arteriovenous malformation observed to bleed from the bile duct and a duodenal ulcer: Report of a case

A 48-year-old man with recurrent episodes of biliary colic and subsequent pancreatitis was admitted to undergo a cholecystectomy. A gastroduodenal fiberscopic examination was performed because of massive melena on the seventh day after adminission. It revealed a shallow ulcer on the posterior wall of a duodenal bulbus with rubor and an exposed vessel, which was clipped endoscopically to stop the bleeding. Further observations showed the papilla of Vater to be bleeding from the papilla. A contrast-enhanced abdominal computed tomography scan demonstrated a dilatation of the common bile duct and several dilated vasculatures around the portal vein, some of which drained into the portal vein. Based on the angiography findings, a diagnosis of arteriovenous malformation in the pancreas head was obtained and an embolization of the gastroduodenal artery was performed. Although the melena subsided, he underwent a pylorus-preserving pancreatoduodenectomy to prevent the recurren of hemorrhaging. The histopathological findings of the bile duct revealed inflammatory cell infiltration and a detachment of the epithelium, except in a small part of the bile duct. A rupture of a damaged vessel inside the bile duct was observed, which was thought to be the cause of hemobilia. Sections of the pancreatic head demonstrated an, inflammatory lesion with fibrosis and saponification as well as a large degree of arteriovenous anastomosis. The patient was discharged on the 35th day after the operation following an uneventful postoperative course.

Is frozen section effective for diagnosis of unsuspected gallbladder cancer during laparoscopic cholecystectomy

Background: Although frozen section is recommended to prevent tumor dissemination following laparoscopic cholecystectomy (LC) for unsuspected gallbladder cancer, there are no reports concretely demonstrating its effectiveness and outcome. Methods: Frozen section during LC was performed in 990 patients with gallstones. The sensitivity, specificity of frozen section, and false-negative cases were evaluated in comparison with postoperative entire cross sections. Results: In frozen section, 983 cases were diagnosed as benign and 7 cases as malignant. Of the benign cases, cancer was discovered in 4 patients postoperatively in which frozen section was diagnosed as regenerative epithelial severe atypia. Sensitivity was 64% and specificity was 100%. Concerning the results of frozen section by p-TNM classification, cancer was diagnosed in 40% of Tis lesions, whereas it was found in 83% of T2 or T3 lesions. Conclusion: Frozen section is effective in cases with T2 or greater lesions for which conversion to radical surgery should be required.

Synergistic antitumor effect by coexpression of chemokine CCL21/SLC and costimulatory molecule LIGHT.

To establish a more efficient treatment for immunotherapy against solid tumors, we have evaluated the antitumor effect by coexpression of a chemokine CCL21/secondary lymphoid tissue chemokine and a costimulatory molecule LIGHT in colon carcinoma C26. C26 cells expressing either CCL21 or LIGHT exhibited a significantly reduced tumor growth in vivo, and mice inoculated with these cells showed a prolonged survival, but eventually all these mice died. In contrast, C26 cells expressing both CCL21 and LIGHT exhibited a minimal tumor growth in vivo, and all these mice survived healthily with a tumor remission and consequently acquired a strong protective immunity. A markedly increased infiltration of mature dendritic cells (DCs), and CD8+ T cells was observed in the tumor mass, and their spleen cells showed a greatly enhanced cytotoxic T lymphocyte (CTL) activity against C26 tumor and interferon (IFN)-γ production. Neutralization of IFN-γ or depletion of CD8+ or CD4+ T cells significantly reduced the antitumor activity. These results suggest that the combined treatment with CCL21 and LIGHT is able to induce a synergistic antitumor effect to eradicate tumor completely by greatly enhancing tumor-infiltration of lymphocytes including mature DCs and CD8+ T cells, resulting in markedly augmented CTL activity and IFN-γ production.

Subphrenic bronchopulmonary foregut malformation with pulmonary-sequestration-like features

A retroperitoneal bronchopulmonary foregut malformation in a 62‐year‐old man is reported. The lesion was composed of mature lung tissue with randomly distributed bronchial structures and ciliated epithelium‐lined cysts, some of which were lined with gastric mucosa. The histological features of this lesion were of both pulmonary sequestration and a bronchogenic, or foregut, cyst, and thus were a unique example of bronchopulmonary foregut malformation with pulmonary differentiation. This case is important in understanding the pathogenesis of foregut anomalies (i.e. bronchopulmonary foregut malformations), which range from pulmonary sequestrations to bronchogenic cysts and foregut duplication cysts.