Biomedical subjects

Takehide Asano

Publications and source records attributed to Takehide Asano.

23 records · Page 2Linked to original sources

PubMedDate not supplied

Modified radiosensitivity of pancreatic cancer xenografts by farnesyl protein transferase inhibitor and MEK inhibitor.

We investigated the effects of the farnesyl transferase inhibitor (FTI) manumycin and the MEK inhibitor PD98059 on growth of human pancreatic cancer, with mutant (SUIT2) or wild-type (BxPC-3) K-ras, xenografted into nude mice. Tumor growth was not reduced by either of the agents at a dose of 3 mg/kg without irradiation. Growth of SUIT2 irradiated at 15 Gy or 30 Gy was reduced by manumycin and PD98059: at 15 Gy, tumor volume doubling time (TVDT) increased from 18.6+/-3.8 to 36.3+/-14.2 days with PD98059 (p<0.05); at 30 Gy, TVDT increased from 32.8+/-6.8 to 70.5+/-10.5 days and 70.7+/-1.5 days, respectively. Manumycin tended to reduce growth of BxPC-3, but the difference in TVDT was not statistically significant. PD98059 significantly increased the TVDT of BxPC-3 at 30 Gy from 34.4+/-18 to 62.6+/-9.8 at 30 Gy. The present results suggest that Ras signaling pathways are potential targets for manipulation of radiosensitivity, and that induction of an alternative pathway may enhance radiosensitivity of pancreatic cancer.

Alkyl and Aryl Transferases↗

PubMedDate not supplied

Radiofrequency ablation therapy for bone metastasis from hepatocellular carcinoma: case report.

BACKGROUND: Radiofrequency ablation (RFA) is one of the standard percutaneous therapies for hepatocellular carcinoma (HCC), but RFA has not been applied to treat bone metastasis from HCC. CASE: A 65-year-old male patient, who underwent hepatectomy for HCC two and a half years previously, complained of pain in his right thigh. Imaging modalities and a needle biopsy revealed metastatic HCC in his right acetabulum. The first RFA therapy was attempted under computed tomography (CT) guidance with 42 Gy radiation therapy. The second RFA therapy was performed for tumor recurrence in his pelvis at 4 years after the first RFA. CONCLUSION: RFA is a safe, easy, repeatable and effective therapy and should be one of the most important therapeutic modalities for bone metastasis from HCC.

Bone Neoplasms↗

PubMedDate not supplied

Intraductal papillary-mucinous tumors of the pancreas.

BACKGROUND/AIMS: To elucidate the risk of malignancy and the morphological alterations associated with malignancy. METHODOLOGY: Thirty cases of intraductal papillary-mucinous tumors and 5 papillary-mucinous carcinomas (invasive intraductal papillary-mucinous tumors) of the pancreas were clinicopathologically and histopathologically analyzed. RESULTS: The invasive carcinoma developed on the basis of severe dysplasia-carcinoma in situ changes and never from mild or moderate dysplasia changes. However, tumor cell projections of intraductal papillary-mucinous tumors encroached into the duct wall and/or the stroma introduced just beneath the epithelium and "intraductal" tumor cells sometimes came in direct contact with the "extraductal" connective tissues even in adenomas. The frankly invasive adenocarcinoma components of invasive intraductal papillary-mucinous tumors were characterized by the lack or poor formation of their own basement membrane and were usually surrounded by the extensive collagenous proliferation, desmoplastic reaction. Such stromal alterations never developed around the "extraductal" components of non-invasive intraductal papillary-mucinous tumors. CONCLUSIONS: The risk of malignancy for an individual intraductal papillary-mucinous tumor was increased with the degree of cellular and/or structural atypia. The desmoplastic reaction with poor formation of the basement membrane is the sine qua non of the "true invasion".

Adenocarcinoma, Mucinous↗

PubMedDate not supplied

Evaluation of CT during arterial portography for preoperative diagnosis of intrahepatic cholangiocarcinoma.

BACKGROUND/AIMS: To evaluate computed tomography during arterial portography for preoperative evaluation in patients with intrahepatic cholangiocarcinoma. METHODOLOGY: Computed tomography during arterial portography was performed in 11 intrahepatic cholangiocarcinoma patients undergoing hepatectomy. Segmental perfusion defect, sensitivity of the main tumor, and sensitivity of intrahepatic metastasis on computed tomography during arterial portography were retrospectively evaluated. RESULTS: In 9 of 11 patients (81.8%), a segmental perfusion defect was seen. The sensitivities for detecting the main tumor and intrahepatic metastasis were 81.8% and 20%, respectively. In 2 patients, the main tumors existed in segmental perfusion defects and thus were not depicted. In 4 false-negative cases, intrahepatic metastatic lesions existed in the segments that were the counterparts of segmental perfusion defects on computed tomography during arterial portography. CONCLUSIONS: The sensitivity of computed tomography during arterial portography for diagnosing intrahepatic cholangiocarcinoma and its intrahepatic metastasis was low due to segmental perfusion defect. It is necessary for intrahepatic cholangiocarcinoma to be subjected to systematic segmentectomy including all areas corresponding to the segmental perfusion defect.

Adult↗

PubMedDate not supplied

Up-regulated expression of the uridine phosphorylase gene in human gastric tumors is correlated with a favorable prognosis.

Uridine phosphorylase (UP) is one of the enzymes involved in 5-fluorouracil (5-FU) activation. The expression was compared in paired specimens from cancerous and non-cancerous regions of gastric, colon and lung cancer patients. Among 28 paired gastric samples, 20 cases showed greater expression in tumors than in normal surrounding tissues and 8 cases showed equal or lower expression levels in tumors. All the gastric patients received 5-FU before and/or after the surgical resection and the prognosis of the patients, whose UP tumor expression increased, was relatively better than that of the patients with equal or less UP gene tumor expression. In contrast, most of the colon (22 cases in total) and all the lung cancer patients (14 in total) did not receive 5-FU and the majority of the colon (12 cases) and lung (10 cases) specimens showed lower expression in the cancerous region. The differential expression between cancerous and non-cancerous regions in colon and lung cancers was not linked with the prognosis. These data suggest that the paired expression level of the UP gene in gastric cancer is a possible prognostic marker for the patients who received 5-FU.

Aged↗