Takehiro Wakasugi

Loss of PTEN expression is associated with colorectal cancer liver metastasis and poor patient survival

BackgroundThe tumour suppressor phosphatase and tensin homolog (PTEN) is an important negative regulator of cell-survival signaling. To evaluate the correlation between PTEN expression and clinicopathological characteristics of colorectal cancer patients with and without liver metastases, we investigated PTEN expression in primary colorectal cancer and colorectal cancer liver metastases.MethodsSixty-nine pairs of primary colorectal cancer and corresponding liver metastasis specimens were analyzed immunohistochemically, and the correlation between immunohistochemical findings and clinicopathological factors was investigated. Seventy primary colorectal cancer specimens from patients without liver metastases were used as controls.ResultsPTEN was strongly expressed in 44 (62.9%) colorectal cancer specimens from patients without liver metastases. In contrast, PTEN was weakly expressed in 52 (75.4%) primary colorectal cancer specimens from patients with liver metastases, and was absent in liver metastases. Weak PTEN expression in colorectal cancer tissues was significantly associated with advanced TNM stage (p < 0.01) and lymph node metastasis (p < 0.05). PTEN expression was significantly stronger in primary colorectal cancer specimens from patients without liver metastases. Furthermore, among colorectal cancer patients with liver metastases, the 5-year survival rate was significantly higher in patients with positive PTEN expression compared to those with negative PTEN expression (p = 0.012).ConclusionOur results suggest that loss of PTEN expression is involved with colorectal cancer aggressive capacity and that diagnostic evaluation of PTEN expression may provide valuable prognostic information to aid treatment strategies for colorectal cancer patients.

PTEN regulate angiogenesis through PI3K/Akt/VEGF signaling pathway in human pancreatic cancer cells

Phosphoinositide 3-kinase (PI3K) pathway exerts its effects through Akt, its downstream target molecule, and thereby regulates various cell functions including cell proliferation, cell transformation, apoptosis, tumor growth, and angiogenesis. Phosphatase and tensin homolog deleted on chromosome 10 (PTEN) has been implicated in regulating cell survival signaling through the PI3K/Akt pathway. However, the mechanism by PI3K/PTEN signaling regulates angiogenesis and tumor growth in vivo remains to be elucidated. Vascular endothelial growth factor (VEGF) plays a pivotal role in tumor angiogenesis. The effect of PTEN on VEGF-mediated signal in pancreatic cancer is unknown. This study aimed to determine the effect of PTEN on both the expression of VEGF and angiogenesis. Toward that end, we used the siRNA knockdown method to specifically define the role of PTEN in the expression of VEGF and angiogenesis. We found that siRNA-mediated inhibition of PTEN gene expression in pancreatic cancer cells increase their VEGF secretion, up-modulated the proliferation, and migration of co-cultured vascular endothelial cell and enhanced tubule formation by HUVEC. In addition, PTEN modulated VEGF-mediated signaling and affected tumor angiogenesis through PI3K/Akt/VEGF/eNOS pathway.

IGF-1 Mediates PTEN Suppression and Enhances Cell Invasion and Proliferation via Activation of the IGF-1/PI3K/Akt Signaling Pathway in Pancreatic Cancer Cells

BACKGROUND Type-1 insulin-like growth factor (IGF-1) up-regulates cell proliferation and invasiveness through activation of PI3K/Akt signaling pathway. IGF-1 also down-regulates the tumor suppressor chromosome 10 (PTEN). We investigated the mechanism by which IGF-1 affects cell proliferation and invasion by suppression of PTEN phosphorylation and interaction with PI3K/PTEN/Akt/NF-small ka, CyrillicB signaling pathway in pancreatic cancer. MATERIALS AND METHODS The expression of IGF-1 receptor (IGF-1R) and PTEN in five pancreatic cancer cell lines was determined by RT-PCR and Western blot. Proliferation and invasion were investigated by WST-1 assay and Matrigel-double chamber assay. Pancreatic cancer cells were transfected with PTEN siRNA to investigate which signaling pathway correlates in regulation of cancer cell proliferation and invasion. RESULTS Five pancreatic cancer cell lines expressed PTEN and IGF-1R in mRNA and protein levels. Suppression of PTEN phosphorylation strongly enhanced cell proliferation and invasion stimulated with IGF-1 via activation of PI3K/Akt/NF-small ka, CyrillicB signaling pathway. In addition, knockdown of PTEN by siRNA transfection also enhanced activation of PI3K/Akt/NF-small ka, CyrillicB pathway, subsequently up-regulating cell invasiveness and proliferation. CONCLUSIONS The IGF-1/PI3K/PTEN/Akt/NF-small ka, CyrillicB cascade may be a key pathway stimulating metastasis of pancreatic cancer cells. We suggest that interfering with the functions of IGF-1/PI3K/Akt/NF-small ka, CyrillicB might be a novel therapeutic approach to inhibit aggressive spread of pancreatic cancer.

Interleukin-1α Enhances Angiogenesis and Is Associated With Liver Metastatic Potential in Human Gastric Cancer Cell Lines

BACKGROUND To better understand the underlying mechanism of liver metastasis formation in human gastric cancer, we evaluated the angiogenic capabilities of human gastric cancer cell lines with different metastatic potentials as well as the role of interleukin (IL)-1alpha in the angiogenic process. MATERIALS AND METHODS Reverse transcription-polymerase chain reaction was used to detect the expression of IL-1alpha and vascular endothelial growth factor (VEGF) mRNA in gastric cancer cell lines with different liver metastatic potentials. Levels of VEGF secreted by human gastric cancer cells were measured by enzyme-linked immunosorbent assay. We also examined how gastric cancer cells with different metastatic potentials influence the proliferation and tube formation of human umbilical vein endothelial cells (HUVECs) using the Premix WST-1 cell proliferation assay system and an angiogenesis assay, respectively. RESULTS IL-1alpha expression levels were significantly correlated with liver metastatic potential in gastric cancer cell lines. Levels of VEGF secreted by gastric cancer cells appear to be regulated by IL-1alpha through IL-1 receptor Type 1 and were correlated with liver metastatic potential. Both HUVEC proliferation and tube formation were strongly enhanced by coculture with high liver-metastatic gastric cancer cells and were enhanced to a similar extent by culture in the presence of IL-1alpha. In contrast, blockade of IL-1alpha inhibited both HUVEC proliferation and angiogenesis. CONCLUSIONS IL-1alpha may play a role in liver metastasis of gastric cancer via enhanced vascular endothelial cell proliferation and angiogenesis.

Middle-colic artery aneurysm associated with segmental arterial mediolysis, successfully managed by transcatheter arterial embolization: report of a case.

An aneurysm of the middle-colic artery, associated with segmental arterial mediolysis (SAM), is a rare condition. This report describes a case of a middle-colic artery aneurysm that was associated with SAM. A 57-year-old man was admitted to our hospital because of severe abdominal pain. A rupture of a middle-colic artery aneurysm was diagnosed by computed tomography, and angiography showed that it may have been associated with SAM. The ruptured aneurysm was successfully treated with transcatheter arterial embolization. Transcatheter arterial embolization might be one of the best treatments for such a complicated aneurysm occurring in a visceral artery.

Granulocyte-colony stimulating factor producing rectal cancer

BackgroundGranulocyte-colony stimulating factor (G-CSF)-producing cancer has been reported to occur in various organs, especially the lung. However, G-CSF-producing colorectal cancer (CRC) has never been reported in the English literature.Case presentationA 57-year-old man was admitted for the surgical removal of a rectal cancer. Some hepatic tumors in the liver were revealed concurrently, and their appearance suggested multiple liver metastases. Low anterior resection was performed. with the help of histopathological examination and immunohistochemical studies, we diagnosed this case to be an undifferentiated carcinoma of the rectum. After the operation, the white blood cell (WBC) count increased gradually to 81,000 cells/μL. Modified-FOLFOX6 therapy was initiated to treat the liver metastases, but there was no effect, and peritoneal dissemination had also occurred. The serum level of G-CSF was elevated to 840 pg/mL (normal range, <18.1 pg/mL). Furthermore, immunohistochemistry with a specific monoclonal antibody against G-CSF was positive; therefore, we diagnosed this tumor as a G-CSF-producing cancer. The patient died from rapid growth of the liver metastases and peritoneal dissemination 2 months after surgery.ConclusionThis is the first case of G-CSF-producing rectal cancer, and its prognosis was very poor.

Successful paclitaxel-based chemotherapy for an alpha-fetoprotein-producing gastric cancer patient with multiple liver metastases.

BackgroundAlpha-fetoprotein (AFP)-producing gastric cancer is known to frequently cause multiple liver metastases and to have an extremely poor prognosis.Case presentationA 64-year-old Japanese man admitted to our hospital was diagnosed with gastric cancer with liver metastases. He underwent a total gastrectomy with splenectomy, and pathological stage IV disease according to the classification proposed by the Japanese Gastric Cancer Association was assigned. The histological diagnosis was poorly differentiated adenocarcinoma, and tumor production of AFP was confirmed by immunohistochemical staining. Following surgery, the patient received combination chemotherapy consisting of TS-1 and paclitaxel. Initially, AFP levels decreased dramatically and computed tomography (CT) revealed regression of liver metastases. However, multiple new liver metastases appeared and serum AFP levels increased after 5 months. A regimen of 5-FU plus paclitaxel followed by paclitaxel monotherapy was used next. Serum AFP levels once again decreased and CT showed regression or disappearance of liver metastases. The patient currently has a very good quality of life, and is receiving weekly paclitaxel monotherapy as an outpatient. No progression of liver metastases has been observed to date.ConclusionWe consider this rare case to have significant value with respect to treatment of AFP-producing gastric cancer with multiple liver metastases, and propose that combining surgery with chemotherapeutic agents such as paclitaxel may lead to a better prognosis in such cases.

Solitary Intraperitoneal Recurrence of α-Fetoprotein-Producing Gastric Carcinoma : Report of a Case

AbstactA solitary recurrence of gastric carcinoma in the peritoneal cavity is extremely rare. We herein present a case of solitary intraperitoneal recurrence in a patient with α-fetoprotein (AFP)-producing gastric carcinoma. As far as we can determine, this is the first report of such a form of recurrence in a patient with gastric carcinoma who underwent a successful resection. A review of our eight patients who had AFP-producing gastric carcinoma showed a frequent association with hepatic metastasis and a poor prognosis as has been reported previously. Our patient received intra-arterial chemotherapy with low-dose cisplatin and 5-fluorouracil to prevent hepatic recurrence, but eventually developed multiple hepatic metastases after ceasing this therapy. Therefore, adjuvant intra-arterial chemotherapy may have altered the site of first recurrence in this patient.

Successful combination chemotherapy with irinotecan hydrochloride and cisplatin for primary gastric small cell carcinoma: report of a case

Primary gastric small cell carcinoma is a rare and aggressive malignant disease with a poor prognosis that was first reported in 1976 by Matsusaka et al. The incidence is very low and the clinicopathological features are similar to those of small cell lung carcinoma.We herein report a case of successful treatment by combination chemotherapy consisting of irinotecan hydrochloride and cisplatin for primary gastric small cell carcinoma. The patient was a 71-year-old male who was admitted to a local hospital with anemia. Gastrointestinal endoscopy revealed the presence of advanced gastric carcinoma at the upper region of the stomach. The patient underwent surgery, and the pathological diagnosis was small cell carcinoma due to the presence of the typical features of small round cells with scant cytoplasm that were positive for synaptophysin and chromogranin A in the resected specimen. The patient underwent subsequent combination chemotherapy, which provided him with over 1 year of survival and a good quality of life. We also present a review of the literature regarding chemotherapy for primary gastric small cell carcinoma.

Advanced Gastric Cancer Identified during Acute Myocardial Infarction: Report of a Case

A 71-year-old man was admitted for acute myocardial infarction. The occluded right coronary artery was immediately reperfused by balloon angioplasty during percutaneous coronary intervention and plans were made to stent the left anterior descending artery and circumflex branch at a later date. Anti-platelet therapy was started after intervention. Ten days after intervention, the patient developed hematemesis. An advanced gastric cancer was identified as the source of the bleed. Although an urgent gastrectomy was indicated, the remaining coronary artery stenoses complicated surgical management. The decision was made to perform the second intervention prior to gastrectomy and to treat the remaining stenoses with bare metal stents. Two months after the second intervention, a total gastrectomy was performed under general anesthesia. No severe cardiac complications occurred during the postoperative period.