Autopsy of anaplastic carcinoma of the pancreas producing granulocyte colony-stimulating factor.

A 50-year-old man presented to a nearby hospital with high fever and anorexia. An abdominal tumor was detected, and he was referred to our hospital. A pancreatic tumor was detected by computed tomography and abdominal ultrasonography. He had high fever, leukocytosis, and high serum granulocyte colony-stimulating factor (G-CSF). We performed a tumor biopsy and histological examination revealed anaplastic carcinoma of the pancreas. Based on the diagnosis, we initiated chemotherapy using gemcitabine plus S-1. However, the tumor rapidly progressed and he deteriorated and died 123 days after admission. As immunohistochemical study showed positive staining for G-CSF in the tumor cell, we diagnosed the tumor producing G-CSF during autopsy. Anaplastic carcinoma of the pancreas producing G-CSF is very rare, with 10 cases, including ours, reported in the literature.

Stroma-directed imatinib therapy impairs the tumor-promoting effect of bone marrow-derived mesenchymal stem cells in an orthotopic transplantation model of colon cancer.

Bone marrow-derived mesenchymal stem cells (MSCs) are reported to contribute to formation of tumor-promoting stromal cells. We reported recently that, in an orthotopic nude mice model of colon cancer, MSCs traveled to tumor stroma, where they differentiated into carcinoma-associated fibroblast (CAF)-like cells. We also found that CAFs express platelet-derived growth factor receptor (PDGFR) at a high level and that imatinib therapy targeting PDGFR in CAFs inhibits growth and metastasis of human colon cancer. These findings led us to examine whether the tumor-promoting effect of MSCs is impaired by blockade of PDGFR signaling achieved with imatinib. Orthotopic transplantation and splenic injection of human MSCs along with KM12SM human colon cancer cells, in comparison with transplantation of KM12SM cells alone, resulted in significantly greater promotion of tumor growth and liver metastasis. The KM12SM + MSC xenograft enhanced cell proliferation and angiogenesis and inhibited tumor cell apoptosis. When tumor-bearing animals were treated with imatinib, there was no significant increase in primary tumor volume or total volume of liver metastases, despite the KM12SM+MSC xenograft, and survival in the mixed-cell group was prolonged by imatinib treatment. Moreover, the ability of MSCs to migrate to tumor stroma was impaired, and the number of MSCs surviving in the tumor microenvironment was significantly decreased. In in vitro experiments, treatment with imatinib inhibited migration of MSCs. Our data suggest that blockade of PDGF signaling pathways influences the interaction between bone marrow-derived MSCs and tumor cells in the tumor microenvironment and, hence, inhibits the progressive growth of colon cancer.

Anti-stromal therapy with imatinib inhibits growth and metastasis of gastric carcinoma in an orthotopic nude mouse model.

Recent studies have revealed that platelet-derived growth factor (PDGF) plays a role in promoting progressive tumor growth in several organs; however, whether PDGF plays such a role in gastric carcinoma is undetermined. We examined whether inhibition of PDGF receptor (PDGF-R) tyrosine kinase signaling by imatinib affects tumor growth and metastasis in an orthotopic nude mouse model of human gastric carcinoma. TMK-1 human gastric carcinoma cells were injected into the gastric wall of nude mice. Groups of mice (n = 10 each) received sterile water (control), low-dose imatinib (50 mg/kg/day), high-dose imatinib (200 mg/kg/day), cancer chemotherapeutic agent irinotecan (5 mg/kg/week), or imatinib (50 mg/kg/day or 200 mg/kg/day) and irinotecan (5 mg/kg/week) in combination for 28 days. Tumor growth and metastasis were assessed. Resected tumors were analyzed immunohistochemically. Carcinoma-associated fibroblasts, pericytes and lymphatic endothelial cells in stroma expressed high levels of PDGF-R; carcinoma cells did not. Treatment with imatinib alone did not inhibit tumor growth and metastasis; however, treatment with irinotecan alone or combined with imatinib significantly inhibited tumor growth. Only treatment with high-dose imatinib and irinotecan in combination inhibited lymph node and peritoneal metastases. Immunohistochemically, only imatinib alone or in combination with irinotecan was shown to significantly decrease the stromal reaction, microvessel area and pericyte coverage of tumor microvessels. These effects were marked with high-dose imatinib. In conclusion, administration of PDGF-R tyrosine kinase inhibitor in combination with irinotecan appears to impair the progressive growth of gastric carcinoma by blockade of PDGF-R signaling pathways in stromal cells.

Potential role for vascular endothelial growth factor-D as an autocrine factor for human gastric carcinoma cells.

Vascular endothelial growth factor (VEGF)-D induces lymphangiogenesis by activating VEGF receptor (VEGFR)-3, which is expressed mainly by lymphatic endothelial cells. VEGFR-3 has also been detected in several types of malignant cells, but the significance of VEGFR-3 expression by malignant cells remains unclear. We examined the expression and function of VEGF-D/VEGFR-3 in human gastric carcinoma cells. Expression of VEGF-D and VEGFR-3 was analyzed in three human gastric carcinoma cell lines and 29 surgical specimens. cDNA microarray analysis was used to examine the effect of VEGF-D on the expression of genes associated with disease progression in VEGFR-3-expressing KKLS cells. VEGF-D-transfected cells and control cells were transplanted into the gastric wall of nude mice. In 10 of the 29 (34%) gastric carcinoma specimens and two of the three cell lines, cancer cells expressed both VEGF-D and VEGFR-3. In vitro treatment of KKLS cells with exogenous VEGF-D increased expression of cyclin D1 and Bcl-2 and stimulated cell proliferation. VEGF-D transfection into KKLS cells resulted in stimulation of angiogenesis, lymphangiogenesis, and cell proliferation, and in inhibition of apoptosis. VEGF-D may participate in the progression of human gastric carcinoma by acting via autocrine and paracrine mechanisms.

Expression of platelet-derived growth factor (PDGF)-B and PDGF-receptor ß is associated with lymphatic metastasis in human gastric carcinoma.

Recent study of murine fibrosarcoma has revealed that platelet-derived growth factor (PDGF) plays a direct role in promoting lymphangiogenesis and metastatic spread to lymph nodes. Thus, we investigated the relation between PDGF and PDGF receptor (PDGF-R) expression and lymphatic metastasis in human gastric carcinoma. We examined PDGF-B and PDGF-Rß expression in four human gastric carcinoma cell lines (TMK-1, MKN-1, MKN-45, and KKLS) and in 38 surgical specimens of gastric carcinoma. PDGF-B and PDGF-Rß expression was examined by immunofluorescence in surgical specimens and in human gastric carcinoma cells (TMK-1) implanted orthotopically in nude mice. Groups of mice (n = 10, each) received saline (control) or PDGF-R tyrosine kinase inhibitor imatinib. PDGF-B and PDGF-Rß mRNA expression was significantly higher in patients with lymph node metastasis than in those without and was also significantly higher in diffuse-type carcinoma than in intestinal-type carcinoma. In surgical specimens, tumor cells expressed PDGF-B, but PDGF-Rß was expressed predominantly by stromal cells. Under culture conditions, expression of PDGF-B mRNA was found in all of the gastric cell lines, albeit at different levels. In orthotopic TMK-1 tumors, cancer cells expressed PDGF-B but not PDGF-Rß. PDGF-Rß was expressed by stromal cells, including lymphatic endothelial cells. Four weeks of treatment with imatinib significantly decreased the area of lymphatic vessels. Our data indicate that secretion of PDGF-B by gastric carcinoma cells and expression of PDGF-Rß by tumor-associated stromal cells are associated with lymphatic metastasis. Blockade of PDGF-R signaling pathways may inhibit lymph node metastasis of gastric carcinoma.

Mesenchymal stem cells enhance growth and metastasis of colon cancer.

Recently, mesenchymal stem cells (MSCs) were reported to migrate to tumor stroma as well as injured tissue. We examined the role of human MSCs in tumor stroma using an orthotopic nude mice model of KM12SM colon cancer. In in vivo experiments, systemically injected MSCs migrated to the stroma of orthotopic colon tumors and metastatic liver tumors. Orthotopic transplantation of KM12SM cells mixed with MSCs resulted in greater tumor weight than did transplantation of KM12SM cells alone. The survival rate was significantly lower in the mixed-cell group, and liver metastasis was seen only in this group. Moreover, tumors resulting from transplantation of mixed cells had a significantly higher proliferating cell nuclear antigen labeling index, significantly greater microvessel area and significantly lower apoptotic index. Splenic injection of KM12SM cells mixed with MSCs, in comparison to splenic injection of KM12SM cells alone, resulted in a significantly greater number of liver metastases. MSCs incorporated into the stroma of primary and metastatic tumors expressed α-smooth muscle actin and platelet-derived growth factor receptor-ß as carcinoma-associated fibroblast (CAF) markers. In in vitro experiments, KM12SM cells recruited MSCs, and MSCs stimulated migration and invasion of tumor cells through the release of soluble factors. Collectively, MSCs migrate and differentiate into CAFs in tumor stroma, and they promote growth and metastasis of colon cancer by enhancing angiogenesis, migration and invasion and by inhibiting apoptosis of tumor cells.

Antibodies to Helicobacter pylori and CagA protein are associated with the response to antibacterial therapy in patients with H. pylori-positive API2-MALT1-negative gastric MALT lymphoma.

The aim of this study was to clarify predictive factors for response to eradication therapy in cases of Helicobacter pylori (H. pylori)-positive API2-MALT1-negative gastric mucosa-associated lymphoid tissue (MALT) lymphoma. Sixty-six patients who were examined for H. pylori infection and the presence of the API2-MALT1 chimeric transcript and who underwent H. pylori eradication therapy as first-line therapy, were enrolled in this study. Immunohistochemical markers (p53, Ki-67, and BCL10), microsatellite instability, loss of heterozygosity, serum levels of antibodies (anti-H. pylori and anti-CagA), and markers for gastritis (gastrin and pepsinogens) were examined, and the results were compared between patients whose tumors regressed completely after eradication therapy (responders) and patients whose tumors did not regress (non-responders). Of the 66 patients with localized gastric MALT lymphoma, 47 (71.2%) showed complete remission after eradication therapy. None of the H. pylori-negative (n = 9) and/or API2-MALT1-positive (n = 7) patients responded to antibacterial treatment. Of 44 patients with H. pylori-positive API2-MALT1-negative gastric MALT lymphoma, 38 (86.4%) showed complete remission after eradication therapy. Titers of antibodies against H. pylori and CagA protein were significantly higher in the responders than in the non-responders (P = 0.0235 and 0.0089, respectively). No significant difference between the groups was observed for the other factors. In conclusion, measurement of titers of serum antibodies to H. pylori and CagA protein may be useful for predicting the response to eradication therapy in patients with H. pylori-positive API2-MALT1-negative gastric MALT lymphoma.

[A case report of anaphylactoid purpura with acute abdominal pain secondary to trauma caused by traffic accident].

A 17-year-old man was admitted to our hospital with multiple fractures resulting from traffic accident. After treatment of fractures, his general status was improved. However, one month after traffic accident, he suffered severe pain in the epigastrium. Ultrasonography and computed tomography showed thickening of the intestinal wall in the duodenum, ileum, and ascending colon. Nineteen days after the onset of abdominal pain, small hemorrhagic spots appeared on both of the lower legs. Subsequently, he developed proteinuria and hematuria. Purpura nephritis was diagnosed in biopsy specimens of the kidney. Anaphylactoid purpura associated with traffic accident is very rare and it is difficult to diagnose without skin and renal symptoms.

Rapid progression of Epstein-Barr-virus-positive gastric diffuse large B-cell lymphoma during chemoradiotherapy: a case report.

A 61-year-old woman was referred to our hospital with epigastralgia and appetite loss. Barium examination and upper gastrointestinal endoscopy revealed uneven erythematous mucosa with multiple elevated lesions from the gastric fornix to the upper corpus. Abdominal computed tomography showed thickening of the wall of the fornix and swelling of perigastric lymph nodes, but whole-body gallium scintigraphy and bone marrow examination did not indicate further involvement. Biopsy specimens showed diffuse infiltration of large atypical lymphoid cells in which Epstein-Barr virus (EBV) was detected by in situ hybridization. Diffuse large B-cell lymphoma (DLBCL), stage II1, was diagnosed. Combination chemotherapy [cyclophosphamide, adriamycin, vincristine, and prednisone (CHOP)], was given, and this was followed by radiotherapy. Partial remission was achieved by chemotherapy, but the disease progressed rapidly during radiotherapy. Because the reported prognosis of EBV-positive DLBCL is unfavorable, the therapeutic strategy for EBV-positive gastric DLBCL should be considered carefully.

[A case of H. pylori and API2-MALT1 gene-negative gastric mucosa-associated lymphoid tissue lymphoma with a carcinoma-like signet-ring cell lymphoepithelial lesion].

A 60-year-old woman presented in February 2003 with an ulcer on the lesser curvature of the anglus. The endoscopic biopsy specimens showed epithelial signet-ring cell associated with lymphoid infiltration, suggesting a diagnosis of gastric cancer. Histopathological examination confirmed the diagnosis of low-grade B-cell lymphoma of MALT with epithelial signet-ring cell lymphoepithelial lesion, which was negative for H. pylori and t (11;18) (q21;q21) translocation (API2-MALT1 gene). This case was treated with H. pylori eradication and additional radiation therapy, and the tumor was disappeared.

A case of multiple hepatic peribiliary cysts which contributed to the obstructive jaundice and led to liver failure at the young man with von Recklinghausen's disease.

We treated a young man with obstructive jaundice, in whom multiple hepatic peribiliary cysts were detected at autopsy. He had been diagnosed with von Recklinghausen's disease in early childhood and had undergone surgery for a ventricular septal defect with massive blood transfusion at the age of 4 years. Examination at the age of 21 revealed prominent splenomegaly and a low platelet count. He underwent splenectomy and liver cirrhosis was confirmed by open biopsy of the liver. He was followed up at a local hospital and was admitted several times. When he was 41 years old, he was transferred to our hospital with severe jaundice and hepatic encephalopathy. Computed tomography showed marked dilation of the intrahepatic bile ducts and liver function tests showed that jaundice was mainly due to an increase of direct bilirubin. Despite endoscopic nasobiliary drainage, plasma exchange, and continuous hemodiafiltration, he died of hepatic failure after 5 days. At autopsy, multiple hepatic peribiliary cysts were found. Although peribiliary cysts have generally been considered to cause no symptoms, this report describes a patient with multiple hepatic peribiliary cysts which appear to have been responsible for the progression of obstructive jaundice.

A case of congenital absence of the portal vein.

We experienced a girl with congenital absence of the portal vein. She was examined by computed tomography (CT), three-dimensional computed tomographic angiography (3DCTA), digital subtraction angiography and liver biopsy. Nodular regenerative hyperplasia of the liver was detected, presumably due to an abnormal hepatocellular response to absent portal flow. 3DCTA showed that the splenic vein and superior mesenteric vein joined to form a common trunk, which directly entered the right atrium. 3DCTA may be a valuable noninvasive tool for identifying portal malformations.