Hiroaki Ohigashi

Fucosylated haptoglobin is a novel marker for pancreatic cancer: A detailed analysis of the oligosaccharide structure and a possible mechanism for fucosylation

Changes in oligosaccharide structures have been reported in certain types of malignant transformations and, thus, could be used for tumor markers in certain types of cancer. In the case of pancreatic cancer cell lines, a variety of fucosylated proteins are secreted into their conditioned media. To identify fucosylated proteins in the serum of patients with pancreatic cancer, we performed western blot analyses using Aleuria Aurantica Lectin (AAL), which is specific for fucosylated structures. An ∼40 kD protein was found to be highly fucosylated in pancreatic cancer and an N‐terminal analysis revealed that it was the β chain of haptoglobin. While the appearance of fucosylated haptoglobin has been reported in other diseases such as hepatocellular carcinoma, liver cirrhosis, gastric cancer and colon cancer, the incidence was significantly higher in the case of pancreatic cancer. Fucosylated haptoglobin was observed more frequently at the advanced stage of pancreatic cancer and disappeared after an operation. A mass spectrometry analysis of haptoglobin purified from the serum of patients with pancreatic cancer and the medium from a pancreatic cancer cell line, PSN‐1, showed that the α 1‐3/α 1‐4/α 1‐6 fucosylation of haptoglobin was increased in pancreatic cancer. When a hepatoma cell line, Hep3B, was cultured with the conditioned media from pancreatic cancer cells, haptoglobin secretion was dramatically increased. These findings suggest that fucosylated haptoglobin could serve as a novel marker for pancreatic cancer. Two possibilities were considered in terms of the fucosylation of haptoglobin. One is that pancreatic cancer cells, themselves, produce fucosylated haptoglobin; the other is that pancreatic cancer produces a factor, which induces the production of fucosylated haptoglobin in the liver.

A new approach to chemoembolization therapy for hepatoma using ethiodized oil, cisplatin, and gelatin sponge

This article reports on a new approach to hepatic arterial chemoembolization therapy using ethiodized oil (Lipiodol, Ultra Fluide), cisplatin, and gelatin sponge (Gelfoam, Upjohn, Kalamazoo, MI) for hepatocellular carcinoma (HCC). The anticancer effects of this therapy on 20 patients who underwent subsequent hepatic resection were evaluated mainly by histologic examination. All main tumors were reduced in size following this therapy. It is notable that in 65% of the patients the tumor size was reduced to less than 50% of that before therapy. All the values of serum α‐fetoprotein (AFP) in the patients who exhibited pretreatment levels exceeding 100 ng/ml dropped by more than 50%, and in 55% of them it fell below 20 ng/ml. The concentration of platinum in the tumor tissue was significantly higher than that in the nontumorous tissue. In 15 of 20 patients (75%), the main nodules were completely necrotic. Thirteen of the patients had daughter nodules and/or small intrahepatic metastases (Group A); nine had tumor emboli in the portal (hepatic) vein (Group B); 17 had intracapsular invasions (Group C); and ten had extracapsular invasions (Group D). The ratios of patients with completely necrotic cancer cells in Group A were nine of 13 (69%); in Group B, seven of nine (78%); in Group C, 11/17 (65%); and in Group D, four of 10 (40%). In eight of the 20 patients (40%) no viable cancer cells were recognized at any foci. Lesions other than those with extracapsular invasion could be considerably eliminated with this form of therapy. It is expected that this method will become the therapy of choice not only for palliative treatment but also for preoperative treatment.

Genome-wide cDNA microarray analysis of gene expression profiles in pancreatic cancers using populations of tumor cells and normal ductal epithelial cells selected for purity by laser microdissection

To characterize molecular mechanism involved in pancreatic carcinogenesis, we analysed gene-expression profiles of 18 pancreatic tumors using a cDNA microarray representing 23 040 genes. As pancreatic ductal adenocarcinomas usually contain a low proportion of cancer cells in the tumor mass, we prepared 95% pure populations of pancreatic cancer cells by means of laser microbeam microdissection, and compared their expression profiles to those of similarly purified, normal pancreatic ductal cells. We identified 260 genes that were commonly upregulated and 346 genes that were downregulated in pancreatic cancer cells. Because of the high degree of purity in the cell populations, a large proportion of genes that we detected as upregulated or downregulated in pancreatic cancers were different from those reported in previous studies. Comparison of clinicopathological parameters with the expression profiles indicated that altered expression of 76 genes was associated with lymph-node metastasis and that of 168 genes with liver metastasis. In addition, expression levels of 30 genes were related to the recurrence of disease. These genome-wide expression profiles should provide useful information for finding candidate genes whose products might serve as specific tumor markers and/or as molecular targets for treatment of patients with pancreatic cancer.

Preoperative indications for extended pancreatectomy for locally advanced pancreas cancer involving the portal vein.

This retrospective study attempted to determine the indications for extended pancreatectomy for locally advanced carcinoma of the pancreas, in terms of postoperative prognosis. An extended pancreatectomy with portal vein or superior mesenteric vein (PV/ SMV) resection and regional lymphadenectomy was performed in 35 of 50 consecutive cancers that extended into the retroperitoneal spaces and involved the PV or SMV. Among the many background factors in the 35 resected specimens, the degree of PV/SMV invasion by the cancer was most closely associated with prognosis, despite resection of all involved PV/SMV. This factor generally correlated with the preoperative findings on the portal phase of superior mesenteric arteriograph. In 17 selected patients in whom PV/SMV invasion had been angiographically both semicircular or less and 1.2 cm (1.4 cm on the film) or less in length, the 3-year survival rate was 59%. This survival rate was significantly higher than the 29% 3-year survival rate in all 35 patients (p < 0.05). Conversely, among the 18 patients in whom invasion was angiographically either beyond semicircular or more than 1.2 cm (1.4 cm on the film) in length, there were no 1.5-year survivors, and this result was even worse than that of 15 nonresectable cases. Based on postoperative survival, the degrees of PV/SMV invasion on preoperative angiography (narrowing pattern and length) are good indicators for aggressive pancreatectomy for locally advanced pancreatic cancer.

Prognostic Significance of Activated Akt Expression in Pancreatic Ductal Adenocarcinoma

Purpose: Akt is a serine/threonine kinase that plays a central role in tumorigenesis. Among the members of Akt family, Akt2 is associated with the development of human cancers. The present study was designed to clarify the prognostic significance of Akt2 and activated Akt expression in pancreatic ductal adenocarcinoma (PDAC). In addition, activated extracellular signal-regulated kinase 1 and 2 (ERK1/2) and the proliferation activity of tumor cells detected by Ki-67 immunohistochemistry were examined. Experimental Design: Immunohistochemical analysis was performed on paraffin-embedded specimens from 65 patients with PDAC; 36 males and 29 females with ages ranging from 48 to 79 years (median, 66 years) of age. Expression levels of Akt2, phosphorylated Akt (p-Akt), and phosphorylated ERK 1/2 (p-ERK 1/2) were categorized as either weaker (low intensity) or equal to stronger (high intensity) compared with those in the endothelial cells of the same specimens. For Ki-67 immunohistochemistry, cases were divided into two groups: level 1, Ki-67 labeling index (LI), <20%; level 2, Ki-67 LI, ≥20%. Results: Twenty-six (42.6%), 28 (45.9%), 39 (63.9%), and 46 (75.4%) of the tumors showed high intensity of Akt2, p-Akt, and p-ERK 1/2 expression, and Ki-67 LI level 2, respectively. A significant positive correlation was observed between Akt2 and p-Akt expression (P < 0.01). Multivariate analysis revealed that p-Akt expression, Ki-67 LI, and histological differentiation are independent prognosticators for PDAC. Conclusions: p-Akt expression is a significant prognostic indicator for PDAC. Inhibition of Akt is a possible molecular approach for treatment of PDAC.

A novel image-guided surgery of hepatocellular carcinoma by indocyanine green fluorescence imaging navigation.

The clear delineation between tumor and normal tissue is ideal for real‐time surgical navigation imaging. We present a novel indocyanine green (ICG) fluorescence imaging technique to visualize hepatocellular carcinoma (HCC).

Detection of Sentinel Node in Gastric Cancer Surgery by Indocyanine Green Fluorescence Imaging: Comparison with Infrared Imaging

BackgroundSecure methods for clinical detection of the sentinel node (SN) are in great demand to avoid unnecessary resection. This was a clinical exploration/feasibility study of a novel detection system for SN biopsy using indocyanine green (ICG) fluorescence imaging in gastric cancer surgery.MethodsSN biopsy using ICG dye was performed in three patients who had gastric cancer. ICG fluorescence images were obtained using a detection system comprising a charge-coupled device (CCD) camera with a cut filter as the detector and light emitting diodes (LED) as the light source. The nodes were also examined simultaneously by an infrared (IR) imaging videoscope.ResultsImmediately after intraoperative ICG injection, the fluorescence imaging system allowed easy visualization of the lymphatic vessels draining from the primary gastric tumor toward the lymph nodes and tracing of the moving injected dye. Some lymph vessels and nodes were hardly recognized by ICG green color or IR imaging. The ICG fluorescence system also allowed visualization of the lymph node when ICG was injected the day before surgery, similar to the radio-guided method.ConclusionsDetection of SNs in gastric cancer surgery using the ICG fluorescence imaging system is a promising novel technique and may perhaps prove useful for laparoscopic surgery.

Overexpressed P-Cadherin/CDH3 Promotes Motility of Pancreatic Cancer Cells by Interacting with p120ctn and Activating Rho-Family GTPases

P-Cadherin/CDH3 belongs to the family of classic cadherins that are engaged in various cellular activities including motility, invasion, and signaling of tumor cells, in addition to cell adhesion. However, the biological roles of P-cadherin itself are not fully characterized. Based on information derived from a previous genome-wide cDNA microarray analysis of microdissected pancreatic ductal adenocarcinoma (PDAC), we focused on P-cadherin as one of the genes most strongly overexpressed in the great majority of PDACs. To investigate the consequences of overexpression of P-cadherin in terms of pancreatic carcinogenesis and tumor progression, we used a P-cadherin-deficient PDAC cell line, Panc-1, to construct a cell line (Panc1-CDH3) that stably overexpressed P-cadherin. Induction of P-cadherin in Panc1-CDH3 increased the motility of the cancer cells, but a blocking antibody against P-cadherin suppressed the motility in vitro. Overexpression of P-cadherin was strongly associated with cytoplasmic accumulation of one of the catenins, p120ctn, and cadherin switching in PDAC cells. Moreover, P-cadherin-dependent activation of cell motility was associated with activation of Rho GTPases, Rac1 and Cdc42, through accumulation of p120ctn in cytoplasm and cadherin switching. These findings suggest that overexpression of P-cadherin is likely to be related to the biological aggressiveness of PDACs; blocking of P-cadherin activity or its associated signaling could be a novel therapeutic approach for treatment of aggressive pancreatic cancers.

Risk of recurrence in a long-term follow-up after surgery in 417 patients with hepatitis B- or hepatitis C-related hepatocellular carcinoma.

Objective:The aim of this study is to clarify the difference of risk of recurrence after hepatic resection between patients with hepatitis B- and hepatitis C-related hepatocellular carcinoma (HCC). Summary and Background Data:HCC is a highly recurrent carcinoma. However, consensus has not yet been reached about the relationship between hepatitis virus types and risk of recurrence in a long-term follow-up for HCC patients who underwent hepatic resection. Patients and Methods:From the beginning of January 1990 to the end of December 1999, of 469 HCC patients who underwent curative hepatic resection, 66 (14%) patients with positive hepatitis B virus surface antigen (HBs-Ag) and negative hepatitis C virus antibody (HCV-Ab) were regarded to have B-type hepatitis (HB)-related HCC (HB-HCC) and 351 (75%) with negative HBs-Ag and positive HCV-Ab were regarded to have C-type hepatitis (HC)-related HCC (HC-HCC). A clinical follow-up was performed to assess the existence of recurrence with the median follow-up periods of 11.0 and 10.1 years for HB- and HC-HCC patients, respectively. Results:The 3-, 5-, and 10-year disease-free survival (DFS) rates of HC-HCC (40%, 24%, and 12%, respectively) were significantly shorter than those of HB-HCC (57%, 54%, and 28%, respectively) (P = 0.0001). In multivariate Cox proportional hazard analysis, viral type, TNM stage, surgical margin, and Edmondsons grade were significantly associated with risk of recurrence. The risk of recurrence from the initial HCC increased to 1.93 times (95% confidence interval, 1.27–2.93) greater in HC-HCC patients than in HB-HCC patients. Conclusion:Hepatitis viral type is an independent factor for recurrence of HCC in a long-term clinical follow-up. This finding suggests that we may need a different strategy to control postoperative recurrence by the viral types in HCC patients.

Liver perfusion chemotherapy via both the hepatic artery and portal vein to prevent hepatic metastasis after extended pancreatectomy for adenocarcinoma of the pancreas

Since hepatic metastasis is a common cause of treatment failure after curative pancreatectomy for adenocarcinoma of the pancreas, we developed a new method of postoperative hepatic perfusion chemotherapy via both the hepatic artery and portal vein. The present study was conducted to determine if this method decreases the hepatic recurrence and improves the survival rate. Following extended pancreatectomy with wide lymphatic and connective tissue clearance for pancreatic cancer, one catheter was placed in the hepatic artery and one in the portal vein. Immediately after surgery, 5-fluorouracil (125 mg/d) was continuously infused via these two routes simultaneously for 28 to 35 days. There were no treatment-related complications in the 20 patients who survived surgery. The 3-year survival rate was 54%, and the cumulative rate of death from hepatic metastasis was 8%. These figures were significantly better than those of our historical control groups. We conclude that this method should be evaluated in a prospective, randomized controlled study.