A case report of hepatocellular carcinoma (Vp4)--an attempt to reduce residual tumor thrombus using combination therapy (hepatic arterial infusion, hepatic arterial embolization and radiation)

A 57-year-old man was found to have elevated levels of HCC markers during an observation of chronic hepatitis C. Diffused hepatoma was involved in the posterior lobe, and tumor thrombus extended into the main portal vein (Vp4). Posterior segmentectomy and tumor thrombectomy were performed. But, CT scan 45 days after the operation showed an enhancement at the residual tumor thrombus in the posterior branch. The patient received a hepatic arterial infusion of 5-FU, followed by hepatic arterial embolization. Then, we chose radiation therapy to the tumor thrombus. The most recent CT showed no enhancement at the reduced tumor thrombus. There have been almost no reports of treatment for residual portal thrombus. Careful observations are necessary in such patients.     

Clinical significant of semiquantificating DNA topoisomerase- I mRNA in colorectal cancer

PURPOSE: To examine the clinical significance of determining the expression levels of DNA topoisomerase- I (topo-I) mRNA of colorectal cancer. METHODS: The relative expression levels of topo-I mRNA in primary colorectal cancer and adjacent normal mucosa were semiquantificated by the RT-PCR method. The relative expression of thymidylate synthase (TS) mRNA of the primary lesions was also examined. RESULTS: The topo- I mRNA expression was higher in the tumorous tissue than in the normal mucosa (n=22, p<0.01). The topo- I mRNA expression did not significantly correlate with 9 clinicopathological variables examined (n=22). In patients who received irinotecan hydrochloride (CPT-11) following the failure of 5-fluorouracil-based treatment, the topoI mRNA expression did not differ nor correlate with the response to CPT-11 (PR, n=14; SD, n=11; PR; n=24) (p=0.91). In these patients, there was no relationship between the topo I mRNA expression and the TS mRNA expression (p=0.22, r=0.18). In addition, the efficacy of CPT-11 did not correlate with combinations subdivided according to the expression levels of topo- I mRNA and TS mRNA. CONCLUSIONS: Determination of topo- I mRNA levels of primary colorectal cancer may not be useful for predicting the efficacy of CPT-11 treatment alone or in combination with TS mRNA levels.     

Significance of HDAC6 regulation via estrogen signaling for cell motility and prognosis in estrogen receptor-positive breast cancer

Histone deacetylase (HDAC) 6 is a subtype of the HDAC family; it deacetylates alpha-tubulin and increases cell motility. Here, we investigate the impact of an alteration of HDAC6 expression in estrogen receptor alpha (ER)-positive breast cancer MCF-7 cells, as we identified that HDAC6 is a novel estrogen-regulated gene. MCF-7 treated with estradiol showed increased expression of HDAC6 mRNA and protein and a four-fold increase in cell motility in a migration assay. Cell motility was increased to the same degree by stably transfecting the HDAC6 expression vector into MCF-7 cells. In both cases, the cells changed in appearance from their original round shape to an axon-extended shape, like a neuronal cell. This HDAC6 accumulation caused the deacetylation of alpha-tubulin. Either the selective estrogen receptor modulator tamoxifen (TAM) or the pure antiestrogen ICI 182,780 prevented estradiol-induced HDAC6 accumulation and deacetylation of alpha-tubulin, leading to reduced cell motility. Tubacin, an inhibitory molecule that binds to the tubulin deacetylation domain of HDAC6, also prevented estradiol-stimulated cell migration. Finally, we evaluated HDAC6 protein expression in 139 consecutively archived human breast cancer tissues by immunohistochemical staining. The prognostic analyses for these patients revealed no significant differences based on HDAC6 expression. However, subset analysis of ER-positive patients who received adjuvant treatment with TAM (n = 67) showed a statistically significant difference in relapse-free survival and overall survival in favor of the HDAC6-positive group (P < 0.02 and P < 0.05, respectively). HDAC6 expression was an independent prognostic indicator by multivariate analysis (odds ratio = 2.82, P = 0.047). These results indicate the biological significance of HDAC6 regulation via estrogen signaling.     

UFD2a mediates the proteasomal turnover of p73 without promoting p73 ubiquitination

p73 protein level is kept extremely low in mammalian cultured cells and its stability may be regulated by not only the ubiquitin/proteasome-dependent proteolysis but also through other unidentified mechanisms. Here, we found for the first time that p73 is physically as well as functionally associated with the U-box-type E3/E4 ubiquitin ligase UFD2a. The immunoprecipitation experiments demonstrated that this interaction is mediated by the COOH-terminal region of p73alpha containing SAM domain. During the cisplatin-induced apoptosis in SH-SY5Y neuroblastoma cells, p73alpha accumulated at a protein level, whereas the endogenous UFD2a was significantly reduced in response to cisplatin. Ectopic expression of UFD2a decreased the half-life of p73alpha in association with a significant inhibition of the p73alpha-mediated transactivation as well as proapoptotic activity. Downregulation of endogenous UFD2a by antisense strategy resulted in a remarkable accumulation of p73alpha. Unexpectedly, UFD2a-mediated degradation of p73alpha was sensitive to the proteasomal inhibitor, however, UFD2a did not affect the ubiquitination levels of p73alpha. Taken together, our present findings imply that UFD2a might promote the proteasomal turnover of p73 in a ubiquitination-independent manner, and also suggest that UFD2a might play an important role in the regulation of cisplatin-induced apoptosis mediated by p73.     

Glucose transporter-1 expression in the thyroid gland: clinicopathological significance for papillary carcinoma

Glucose transporter-1 (GLUT-1) expression was immunohistochemically analysed in a total of 268 cases of thyroid gland disease, including 129 cases of papillary carcinoma (PC), 60 cases of follicular carcinoma (FC), 57 cases of follicular adenoma, and 22 cases of adenomatous goitre. Seventy-one percent (91/129) of PC cases showed GLUT-1 expression, semi-quantitatively evaluated as: +, 21 cases (16%); 2+, 37 cases (29%); 3+, 33 cases (26%); and negative, 38 cases (29%). These positive cases were divided into two groups: 'membrane-like' pattern in 24 cases (19%), and 'cytoplasm-predominance' pattern in 67 cases (52%). GLUT-1 expression was observed in 5% (3/60) of FC cases, but all follicular adenomas and adenomatous goitres were negative for GLUT-1 (PC vs. FC, p<0.0001). Membrane-like expression was observed more frequently in non-organ-confined PCs (pT4) than in organ-confined PCs (pT1, 2, and 3) (p=0.0056). Seventy-five percent (18/24) of PC cases showing membrane-like expression were non-organ-confined. The membrane-like pattern was observed more frequently in PCs with lymph node (LN) metastasis compared to those without (p=0.0036). Ninety-two percent (22/24) of PC cases showing the membrane-like pattern were not organ-confined. Semi-quantitative analysis of glut-1 mRNA by RT-PCR showed a tendency toward higher expression in PCs compared to FCs, follicular adenomas and adenomatous goitres, and the mRNA expression in PCs with a membrane-like pattern was higher than those showing cytoplasm-predominance. We concluded that: 1) GLUT-1 is immunohistochemically useful in distinguishing PC from FC and benign diseases; 2) GLUT-1 may play an important role in the advancement of PC and LN metastasis, and its membrane-like expression is of more clinical significance than the cytoplasm-predominance pattern; and 3) glut-1 mRNA expression corresponds with the immunohistochemical expression profile.     

In vitro drug resistance to imatinib and mutation of ABL gene in childhood Philadelphia chromosome-positive (Ph+) acute lymphoblastic leukemia

Imatinib, the ABL kinase inhibitor, is used not only for Philadelphia chromosome-positive (Ph + ) chronic myelogenous leukemia, but also for Ph + acute lymphoblastic leukemia (ALL), although resistance to the drug tends to develop in an early stage of the clinical course. We describe a childhood refractory Ph + ALL patient in whom progressive resistance to imatinib was correlated with the appearance of a mutation in the BCR-ABL kinase domain and in vitro drug resistance to imatinib as determined by the methyl-thiazol-tetrazolium (MTT) assay. A missense mutation of T to C (Y253H) of the ABL gene was identified in the resistant clone, suggesting that this mutation may play an etiological role in the rapid loss of drug sensitivity.     

Regional difference in P-glycoprotein function in rat intestine

It has been reported that inhibition of the P-glycoprotein (P-gp) results in the improved absorption of P-gp substrate in the intestinal tract. In fact, the increased permeability of P-gp substrate across the intestinal epithelium was observed following inhibition of P-gp in in vitro experiments. To develop the formulation containing P-gp inhibitor and P-gp substrate for practical use, it is necessary to know whether the results obtained in the in vitro experiments are reproducible at whole body level. It is also important to find out the regional difference of the P-gp activity in the intestinal tract. In this study, we examined whether verapamil, a specific inhibitor of P-gp, improves the absorption of rhodamine123 (Rho123), a substrate of P-gp, from the jejunum, ileum, and colon of rats using the in situ loop method. The water content in the loop decreased during the experiment, resulting in a significant change of the Rho123 concentration in the loop. Thus, to accurately determine the absorption rate of Rho123, it was necessary to measure the water movement. It was found that there was a regional difference in the water movement, i.e., greatest in colon, followed by ileum. Verapamil did not change the water movement in any intestinal regions. When the concentration of Rho123 in the loop was corrected by water movement, the Rho123 clearance was in the order of ileum (1.15 microL/min/cm), colon (0.83 microL/min/cm) and jejunum (0.47 microL/min/cm). In the presence of verapamil, the Rho123 clearance was significantly increased at jejunum and ileum but not in colon (ileum: 2.08 microL/min/cm, colon: 1.14 microL/min/cm, jejunum: 1.28 microL/min/cm). These results suggest that P-gp inhibits the drug absorption in jejunum and ileum. From these results, it is possible to evaluate the role of P-gp and its regional difference in the in situ experiments. In particular, the inhibition of P-gp results in an increase in absorption of the P-gp substrate limited to jejunum and ileum.     

Estimation of detection limit from slope of B/B0 in competitive ELISA

A method has been proposed for determining the detection limit (L(D)) from the slope of a semilogarithmic plot of a B/B(0) curve in competitive enzyme linked immunosorbent assay (ELISA). As an application, this paper describes a graphic determination of L(D) from analogue data in the literature. The L(D) obtained corresponds to the concentration at which the relative standard deviation of concentration estimates is 30%.     

Nicardipine, a calcium antagonist, does not aggravate intracerebral haemorrhage in an intracerebral haemorrhage model in rats

Despite controversy over their safety in patients with intracerebral haemorrhage, calcium antagonists are widely used in the treatment of hypertensive emergencies. Here, we investigated the effects of nicardipine on haematoma size and neurological deficit in a rat model of collagenase-induced intracerebral haemorrhage. Injection of collagenase (0.014 U) into the striatum induced haematoma (19.9+/-3.4 mm(3)) in the striatum and brain oedema. Drugs were infused from 30 min after collagenase injection for 3 h under conscious conditions. Nicardipine intravenously at 0.1, 1 and 10 microg kg(-1) min(-1) affected neither haematoma size nor the degree of brain oedema. Nicardipine at these doses provided a stable and dose-dependent decrease in mean blood pressure of 6%, 13% and 33%, respectively, with an increase in heart rate that was apparently caused reflexively. Further, nicardipine did not aggravate the neurological deficits in these intracerebral haemorrhage rats, primarily forearm flexion behaviour on suspension by the tail and circling behaviour. These results indicate that nicardipine infusion stably decreased blood pressure without affecting intracerebral haemorrhage in an intracerebral haemorrhage model in rats.