Essential and instructive roles of GATA factors in eosinophil development.

GATA transcription factors are major regulators of hematopoietic and immune system. Among GATA factors, GATA-1, GATA-2, and GATA-3 play crucial roles in the development of erythroid cells, hematopoietic stem, and progenitor cells, and T helper type 2 (Th2) cells, respectively. A high level of GATA-1 and GATA-2 expression has been observed in eosinophils, but their roles in eosinophil development remain uncertain both in vitro and in vivo. Here we show that enforced expression of GATA-1 in human primary myeloid progenitor cells completely switches myeloid cell fate into eosinophils. Expression of GATA-1 exclusively promotes development and terminal maturation of eosinophils. Functional domain analyses revealed that the COOH-terminal finger is essential for this capacity while the other domains are dispensable. Importantly, GATA-1-deficient mice failed to develop eosinophil progenitors in the fetal liver. On the other hand, GATA-2 also showed instructive capacity comparable to GATA-1 in vitro and efficiently compensated for GATA-1 deficiency in terms of eosinophil development in vivo, indicating that proper accumulation of GATA factors is critical for eosinophil development. Taken together, our findings establish essential and instructive roles of GATA factors in eosinophil development. GATA-1 and GATA-2 could be novel molecular targets for therapeutic approaches to allergic inflammation.

Clonal identification and characterization of self-renewing pluripotent stem cells in the developing liver.

Using flow cytometry and single cell-based assays, we prospectively identified hepatic stem cells with multilineage differentiation potential and self-renewing capability. These cells could be clonally propagated in culture where they continuously produced hepatocytes and cholangiocytes as descendants while maintaining primitive stem cells. When cells that expanded in vitro were transplanted into recipient animals, they morphologically and functionally differentiated into hepatocytes and cholangiocytes with reconstitution of hepatocyte and bile duct structures. Furthermore, these cells differentiated into pancreatic ductal and acinar cells or intestinal epithelial cells when transplanted into pancreas or duodenal wall. These data indicate that self-renewing pluripotent stem cells persist in the developing mouse liver and that such cells can be induced to become cells of other organs of endodermal origin under appropriate microenvironment. Manipulation of hepatic stem cells may provide new insight into therapies for diseases of the digestive system.

[A case of liver metastatic recurrence of bile duct cancer completely responding to single-drug S-1 chemotherapy].

A 65-year-old man with common bile duct cancer was treated by pylorus-preserving pancreaticoduodenectomy with D2 lymph node dissection. Three months after surgery, tumor marker was increasing, and CT demonstrated multiple liver metastatic tumors. Single drug chemotherapy with S-1(100 mg/body/day)was administered. After 6 months, the liver metastatic tumors could not be visualized by CT. S-1 may be the chemotherapy of choice for recurrence of bile duct cancer.

Expression and prognostic roles of beta-catenin in hepatocellular carcinoma: correlation with tumor progression and postoperative survival.

PURPOSE: Although hepatocellular carcinoma (HCC) is the most common primary malignant tumor of the human liver, the molecular changes and mechanisms that regulate its development and progression remain unclear. In the present study, we investigated the correlation between beta-catenin expression and clinical outcome in 51 patients with relatively small (maximal diameter < 30 mm), solitary HCCs. EXPERIMENTAL DESIGN: The tumors were classified according to histological tumor differentiation (grade I, 11 tumors; grade II, 28 tumors; grade III, 12 tumors). Using immunohistochemical methods to detect nuclear accumulation of beta-catenin, we investigated the correlation between beta-catenin expression and clinical outcome and compared the correlation with cyclin D1, Ki-67, and E-cadherin. RESULTS: Focal or generalized nuclear beta-catenin expression was observed in 36.4% (4 of 11) of the grade I tumors, 39.3% (11 of 28) of the grade II tumors, and 25% (3 of 12) of the grade III tumors. Nuclear beta-catenin-positive grade III tumors were associated with significantly poorer survival (P = 0.004), whereas none of the patients with nuclear beta-catenin-negative grade I tumors died. With regard to proliferative activity, positive nuclear beta-catenin staining correlated significantly with an increased Ki-67 labeling index in grade I (P < 0.0001) and grade III (P = 0.0045) tumors and with reduced epithelial cadherin expression in the cell membrane (P < 0.001). In contrast, no association with the expression of cyclin D1, one of the target factors of beta-catenin, was detected. CONCLUSIONS: Our present data suggest that beta-catenin plays important roles in promoting tumor progression by stimulating tumor cell proliferation and reducing the activity of cell adhesion systems and is associated with a poor prognosis, especially in patients with poorly differentiated HCCs.

APC0576: a novel small molecule, immunosuppressive agent effective in primate models.

BACKGROUND: APC0576, 5-(((S)-2,2-dimethylcyclopropanecarbonyl)amino)-2-(4-(((S)-2,2-dimethylcyclopropanecarbonyl)amino)phenoxy)pyridine is a novel synthetic compound with an inhibitory activity on NF-kappaB-dependent gene activation and chemokine synthesis in human endothelial cells. This article describes the effect of APC0576 on T-cell-dependent immune functions in vitro and in vivo in primate models, because NF-kappaB is known to be one of the potent mediators in T-cell activation. METHODS: The effects of APC0576 on interleukin-2 production and proliferative responses in human peripheral blood mononuclear cells were studied under various stimuli with in vitro culture assay. Next, female rhesus monkeys were immunized with tetanus toxoid (TTx), and APC0576 was orally administered for 4 weeks. Serum-specific antibody for TTx was monitored weekly using an enzyme-linked immunosorbent assay, and delayed-type hypersensitivity reaction was examined after 4 weeks of APC0576 treatment. To evaluate the immunosuppressive activity, APC0576 was orally administered for 32 days to rhesus monkeys that received transplants of allogeneic kidney. RESULTS: APC0576 effectively suppressed interleukin-2 production and proliferation in activated human peripheral blood mononuclear cells. Both delayed-type hypersensitivity reaction and specific antibody formation evoked by TTx was significantly and dose-dependently attenuated by 4 weeks treatment of APC0576 without any serious toxicologic signs. Allogeneic kidneys grafted in rhesus monkeys were not rejected and fully functioned during the 32 days of APC0576 treatment, although they were rapidly rejected after the withdrawal of the drug. CONCLUSIONS: A novel, orally available immunosuppressive agent, APC0576, effectively inhibited T-cell-based immune responses both in vitro and in vivo. APC0576 may have potential for a therapeutic agent in clinical organ transplantation and various cytokine-mediated diseases.

Auxiliary partial orthotopic liver transplantation for fulminant hepatitis: regeneration of the diseased native liver in a pig model.

BACKGROUND: This study was performed to develop a clinically relevant porcine model of auxiliary partial orthotopic liver transplantation (APOLT) for fulminant hepatic failure. METHODS: FHF was induced by intraportal administration of alpha-amanitin and lipopolysaccharide. Thereafter, pigs were divided into four groups. Group 1 was an untreated, control group. In group 2, pigs underwent only a left hemihepatectomy. Pigs in groups 3 and 4 received APOLT after hemihepatectomy. Tacrolimus was administered to pigs in group 4, but not to those in group 3. RESULTS: Two-week survival rates were 0%, 20%, 40%, and 100% for groups 1, 2, 3, and 4, respectively. In group 4, after abolishing the graft function at 1 week, pigs survived for more than 2 weeks, and regeneration of the native liver was confirmed histologically. CONCLUSIONS: Pigs suffering from fulminant hepatic failure could achieve long survival and liver regeneration with a temporary support of the auxiliary graft.

Evidence for hepatocyte differentiation from embryonic stem cells in vitro.

We confirmed hepatocyte differentiation from embryonic stem (ES) cells in vitro. RT-PCR analysis revealed that a broad range of hepatic gene expression was observed in ES cells differentiated through formation of embryoid bodies (EBs) and its attachment culture. Quantitative PCR analysis revealed that hepatic gene expression related to early and late-stage liver development were enhanced through in vitro differentiation of ES cells. The presence of albumin-producing cells in the peripheral region of attached EBs was confirmed by immunocytochemical analysis. Future experiments will reveal the molecules that induce hepatocyte differentiation from ES cells in vitro. This research will provide systems for the investigation of mechanisms in liver development and establish a method of ES cell-based therapy for liver diseases.

Establishment of clonal colony-forming assay system for pancreatic stem/progenitor cells.

Pluripotent stem cells found in a number of organs are usually in small cell populations. However, under adaptive stimulation, they enter the stage of growth and differentiation to compensate for the loss of differentiated cells. To analyze stem cell potential precisely, the exclusion of other differentiated cells and a clonal assay system are strongly required. In this study, we established a colony-forming assay system for pancreatic stem/progenitor cells in vitro. In this culture condition, they received signals for growth and differentiation, and formed clonal colonies including pancreatic endocrine-lineage cells, such as alpha and beta cells. By combining this culture system with flow cytometric cell sorting, pancreatic stem/progenitor cells will be enriched, and their potential can be analyzed precisely in single cell-based experiments.

Neovascularization in pancreatic ductal adenocarcinoma: Microvessel count analysis, comparison with non-cancerous regions and other types of carcinomas.

Although neovascularization is regarded as an essential factor for tumor growth, it is unclear whether pancreatic adenocarcinoma is also influenced by this process. Furthermore, the reported microvessel count (MVC) data can not be compared due to the diversity of evaluating methods, and the relation between MVC data and metastatic potentials remains controversial. A total of 24 pancreatic adenocarcinomas and 24 adjacent non-cancerous pancreatic parenchyma were analyzed for MVC using anti-CD31 antibody. In addition, the MVC of 15 hypervascular tumors (10 hepatocellular carcinomas: HCC and 5 islet cell pancreatic tumors: ICT), 30 other types of adenocarcinomas (10 gastric, 10 colon and 10 intraductal papillary mucinous tumors of the pancreas: IPMT), as well as that of non-cancerous areas, were also analyzed. The extent of hepatic and peritoneal spread in 24 pancreatic adenocarcinoma patients was classified and correlations with MVC were evaluated. The mean MVC of 24 pancreatic adenocarcinomas (31.6 +/- 11.1) was actually lower than that of HCCs (91.6) or ICTs (56.4). The diversity is temperate as compared with that of other adenocarcinomas, i.e., 42.9 in gastric carcinomas, 35.6 in colon carcinomas and 32.5 in IPMT. MVC in non-cancerous areas were significantly higher in the pancreas (112.8) than in the stomach (29.6) or colon (26.3). MVC ratios of the cancerous area to the non-cancerous area were significantly lower in the pancreas (0.2818 +/- 0.100) than in the stomach (1.569 +/- 0.526, p<0.001) or the colon (1.423 +/- 0.493, p<0.001). MVC were higher in diffuse hepatic metastasis patients (36.0) than in limited metastasis patients (25.7). In conclusion, MVC in pancreatic adenocarcinoma revealed vascular volume to actually be lower than that of hypervascular tumors. We believe, however, that this hypovascularity is due mainly to contrast with the hyper-vascular non-cancerous pancreas, since MVC in the cancerous area itself was at the same level as in other adenocarcinomas. In addition, we revealed MVC to be of value for predicting the extent of liver metastasis.

Treatment and prognosis in colorectal cancer patients with bone metastasis.

We have reviewed the cases of every patient presenting with bone metastasis after colorectal surgery and tried to establish the features of this clinical entity and generate basic strategies to the therapeutic management of this condition. Of 928 primary tumor resected colorectal cancer patients, 12 (1.3%) were identified with bone metastasis and included in this study. The majority of primary tumors were located at the rectosigmoid portion of the colon. All cases were highly advanced at the time of diagnosis, including 8 cases of stage IV by TNM classification. Sites of metastatic tumors were concentrated in lumber or pelvic bones. At the onset of bone metastasis, 9 of the 12 cases had other metastatic sites, i.e., only 3 patients had bone metastasis alone. Survival after onset of bone metastasis was very poor, with a median survival of approximately 5 months and a 20% survival rate at 1 year. With regard to cause of death, seven patients died of pulmonary failure, one of liver failure, and one of DIC. Only 2 cases of solitary osseous metastasis have survived more than 1 year. In order to significantly improve prognosis, the early detection of bone metastases is important.

Effect of fat volume on postoperative complications and survival rate after D2 dissection for gastric cancer.

BACKGROUND: D2 lymph node dissection in gastric cancer is controversial in Western countries because of the relatively high complication and mortality rates. The purpose of this study was to clarify the effects of fat volume on operation factors, postoperative complications, and survival in gastric cancer surgery.METHODS: We studied 293 consecutive patients who had undergone distal gastrectomy with D2 dissection for gastric cancer at our hospital between 1990 and 1997. The patients were classified into three groups according to their body mass index (BMI; kg/m(2)). We analyzed differences in the operation time, the amount of blood loss, the postoperative complications and the survival rate among the three groups.RESULTS: Group A patients had a BMI of less than 20 ( n = 61), group B had a BMI of 20-25 ( n = 178), and group C had a BMI of more than 25 ( n = 54). There were significant differences in operation time (group A, 206 +/- 66 min; group B, 226 +/- 61 min; group C, 252 +/- 61 min; P < 0.05), blood loss (group A, 417 +/- 282 ml; group B, 501 +/- 295 ml; group C, 605 +/- 333 ml; P < 0.05), and postoperative complications (group A, 3.3%; group B, 5.6%; group C, 22.0%). There were significant differences in postoperative complications between groups A and C, and between groups B and C. However, the difference between groups A and B was not significant, and no significant difference in survival rate was seen among the three groups.CONCLUSION: Fat volume definitely increases the postoperative complications. Accordingly, the high rate of postoperative complications of D2 surgery in Western countries may be related to the patients' relative obesity.

Accompanying liver cirrhosis as a risk factor for recurrence after resection of solitary hepatocellular carcinoma.

BACKGROUND/AIMS: A high recurrence rate after hepatic resection adversely influences the postoperative prognosis of patients with hepatocellular carcinoma. In the present study, long-term results and prognostic factors were evaluated in patients who underwent hepatic resection for solitary hepatocellular carcinoma. METHODOLOGY: The records of 105 patients who underwent hepatic resection for hepatocellular carcinoma between June 1978 and April 2000 were retrospectively reviewed. In 61 patients with solitary hepatocellular carcinoma who survived the curative operation, the prognostic significance of 11 clinicopathological parameters was investigated by univariate and multivariate analyses. RESULTS: After curative resection, the cumulative survival rate at 5 years in these 61 patients with solitary hepatocellular carcinoma was significantly better than in 25 patients with multiple hepatocellular carcinomas (44% vs. 25%, p = 0.01). However, even in the solitary group, the cumulative recurrence-free survival rate at 5 years was only 32%; and in 27 (75%) of 36 patients, in whom recurrence was confirmed within 5 years, hepatocellular carcinoma recurred within 2 years. Multivariate analysis disclosed that only accompanying liver cirrhosis was a variable having prognostic significance for overall and recurrence-free survival. A study of other clinicopathological factors, including tumor size, failed to demonstrate any prognostic value. CONCLUSIONS: The present result suggests that hepatic resection can be indicated in patients with solitary hepatocellular carcinoma, irrespective of its size. Though the postoperative recurrence associated with the underlying cirrhosis is still frequent, long-term survival can be expected if the recurrent tumors are successfully treated by a strategy using multiple modalities.

Pancreatic carcinoid: transcatheter arterial chemoembolization of liver metastases.

Carcinoid tumors are a common disease in the gastrointestinal tract, but are extremely rare in pancreas. To our knowledge, only 33 carcinoid tumors of pancreas have been reported in the English literature. Complete surgical resection of pancreatic carcinoid contributes to prolonged survival. But distant metastases, including liver metastasis, prevent long-term survival. We report here one resected case of pancreatic carcinoid tumor with liver metastases. Postoperatively, multiple liver metastases had arisen in the bilateral lobe of the liver and were treated with transcatheter arterial chemoembolization. In this case, transcatheter chemoembolization was effective for palliation for postoperative liver metastases.

Resection of localized recurrences after hepatectomy of colorectal cancer metastases.

BACKGROUND/AIMS: Hepatectomy is generally considered the only mode of curative treatment available for patients with colorectal liver metastases, even though recurrence occurs in more than 60% of the patients. METHODOLOGY: This is a retrospective study examining the survival of 11 patients undergoing surgical excision of recurrences gained from 46 patients undergoing initial hepatectomy for metastatic colorectal cancer. These 46 patients had curative hepatectomy and no extrahepatic metastasis. RESULTS: Cancer recurred in 29 of the 46 patients after a median follow-up time of 29.5 months (range 2-183 months), and 11 had curative resection of localized recurrences. In 6 patients, the liver was the only site of recurrence and 4 patients had isolated lung metastases. One patient had liver and lung metastases. There was no perioperative mortality. The median survival time and cumulative 5-year survival rate for 11 patients after the repeated resection were 28 months and 43.8%, respectively. These results were comparable to the survival for 46 patients after the initial hepatectomy, in which the median survival was 29.5 months and the 5-year survival rate was 49.0%. CONCLUSIONS: In appropriately selected patients with colorectal cancer, surgical excision of localized recurrences after hepatectomy may be effective in prolonging survival.

Liver repopulation by c-Met-positive stem/progenitor cells isolated from the developing rat liver.

BACKGROUND/AIMS: Self-renewing stem cells responsible for tissue or organ development and regeneration have been recently described. To isolate such cells using flow cytometry, it should be required to find molecules expressing on their cell surfaces. We have previously reported that, on cells fulfilling the criteria for hepatic stem cells, the hepatocyte growth factor receptor c-Met is expressed specifically in the developing mouse liver. In this study, to determine whether c-Met is an essential marker for hepatic stem cells in other animal strains, we examined the potential for in vivo liver-repopulation in sorted fetal rat-derived c-Met+ cells using the retrorsine model. METHODOLOGY: Using flow cytometry and monoclonal antibodies for c-Met and leukocyte common antigen CD45, fetal rat liver cells were fractionated according to the expression of these molecules. Then, cells in each cell subpopulation were sorted and transplanted into the retrorsine-treated adult rats with two-third hepatectomy. At 9 months post transplant, frequency of liver-repopulation was examined by qualitative and quantitative analyses. RESULTS: When we transplanted c-Met+ CD45- sorted cells, many donor-derived cells formed colonies that included mature hepatocytes expressing albumin and containing abundant glycogen in their cytoplasm. In contrast, c-Met- cells and CD45+ cells could not repopulate damaged recipient livers. CONCLUSIONS: High enrichment of liver-repopulating cells was conducted by sorting of c-Met+ cells from the developing rat liver. This result suggests that c-Met/HGF interaction plays a crucial role for stem cell growth, differentiation, and self-renewal in rat liver organogenesis. Since the c-Met is also expressed in the fetal mouse-derived hepatic stem cells, this molecule could be expected to be an essential marker for such cell population in the various animal strains, including human.

Refractory proctosigmoiditis probably caused by inferior mesenteric vein ligation at sigmoidectomy.

A case of refractory proctosigmoiditis is reported in a 65-year-old female post-sigmoidectomy patient. She had bloody diarrhea and abdominal pain 2 years after sigmoidectomy, in which the inferior mesenteric vein was ligated close to the inferior mesenteric artery root during the lymph node dissection, while the inferior mesenteric artery trunk and the last branch of the sigmoid arteries was preserved. The biopsied specimen obtained by a fiber optic colonoscopy was diagnosed as proctitis. Antidiarrheals, 5-aminosalicylic acid and steroid enemas showed only limited therapeutic effects. An angiography revealed a mild degree of rectal artery dilatation and tiny venous angiogenesis detected on the delayed phase images. Because the inferior mesenteric vein had been ligated, collateral veins developed to drain the blood on the distal side of the anastomosis to bilateral internal iliac veins. The venous blood of the descending colon (oral side of anastomosis) drained to left colic vein. The cause of rectosigmoiditis was considered to be venous congestion due to the inferior mesenteric vein ligation. A rectosigmoidectomy with reanastomosis using a double-stapling technique was performed, and the patient was discharged without symptoms.

A resected case of metachronous liver metastasis from lung cancer producing alpha-fetoprotein (AFP) and protein induced by vitamin K absence or antagonist II (PIVKA-II).

A resected case of huge liver metastasis of hepatoid adenocarcinoma of the lung is described. A 77-year-old man who presented a solitary huge liver tumor was admitted to our hospital. He had undergone right lower lobectomy of the lung for lung cancer one year before. The view of imaging studies was not a typical one of hepatocellular carcinoma. Serum levels of AFP and PIVKA-II were 334,500ng/mL and 3,890mAU/mL, respectively, and the proportion of AFP L3 was 97.9%. It was thought that they were strongly diagnostic for hepatocellular carcinoma. Extended right lobectomy of the liver was performed. Microscopically, it was poorly differentiated adenocarcinoma and diagnosed as liver metastasis from the formerly resected lung cancer. The tumor was composed of cells with both sheet-like growth and tubule formation. The neoplastic cells, in the sheet-like growth resembled hepatocellular carcinoma cells. By immunohistochemical staining with anti-AFP and anti-PIVKA-II antibodies, cancer cells of both the primary and metastatic lesions were positive. The patient eventually died of multiple liver and bone metastasis 6 months after the operation.

E-cadherin expression in the primary tumors and metastatic lymph nodes of poorly differentiated types of rectal cancer.

PURPOSE: Dysfunction of E-cadherin, a cell-cell adhesion molecule, correlates with the grade of dedifferentiation and/or invasiveness of rectal cancer. However, the relationship between E-cadherin expression in the primary tumor and the potential for metastasis has never been reported. METHODS: E-cadherin expression in 43 primary rectal cancer, including 10 poorly differentiated type, and their associated metastatic lymph nodes (LN mets.) were immunohistochemically evaluated. RESULTS: Heterogeneous immunostaining, suggestive of damage to the E-cadherin-mediated cell-cell adhesion system, was seen in 13 of the 28 LN mets positive primary lesions, but in 0 of the 15 LN mets negative primaries. Furthermore, the incidence of heterogeneous immunostaining differed significantly between poorly differentiated and differentiated cancers, being seen in 8 of 10 cases and 5 of 33 cases, respectively (P = 0.0003 by Fisher's exact test). Interestingly, most of the LN mets. foci (25 of 28 cases) showed homogeneous staining regardless of the E-cadherin staining pattern of the primary lesion. CONCLUSION: Heterogeneous immunostaining of E-cadherin in poorly differentiated rectal cancer was associated with lymph node metastasis. Its staining pattern in metastatic lymph nodes were, however, generally homogenous.

Impaired proliferative response of V alpha 24 NKT cells from cancer patients against alpha-galactosylceramide.

Human invariant V alpha 24(+) NKT cells are a relatively new subpopulation of lymphocytes. It has been reported that V alpha 24 NKT cells are significantly involved in some human diseases. We have evaluated the number and function of V alpha 24 NKT cells in both healthy volunteers and cancer patients. In this study we found that V alpha 24 NKT cells in unfractionated PBMCs obtained from cancer patients did not respond efficiently to alpha-galactosylceramide (alpha-GalCer) in vitro. Thus, their proportion after stimulation with alpha-GalCer was smaller than that found in healthy volunteers. However, the cancer patients' V alpha 24 NKT cells retained cytotoxic activity against malignant target cells, and they could efficiently proliferate to alpha-GalCer when fractionated by sorting. Furthermore, we found that addition of G-CSF to the culture could restore the low proliferative response of V alpha 24 NKT cells from cancer patients. These results suggest that some functions of NKT cells in cancer patients are impaired, and this observation carries significant implications for immunotherapy-based cancer treatments.