Regulation of renal cytochrome P450s by thyroid hormone in diabetic rats

Effects of thyroid hormone treatment on renal P450 expression in the diabetic rats were investigated. Diabetes produced by streptozotocin induced CYP4A2 and P450 K-2 (similar form with CYP2C23) but not P450 K-4 (similar form with CYP4A8) and induced lauric acid hydroxylation activity. The serum thyroid hormone level was decreased with diabetes. Treatment of diabetic rats with thyroid hormone (T3) as well as with insulin reversed the increase in the levels of CYP4A2 and P450 K-2. Thyroidectomy also induced CYP4A2 and P450 K-2 in the rat kidney. The increase was reversed by treatment of thyroidectomized rats with T3. These findings suggest that expression of CYP4A2 and P450 K-2 in rat kidney is suppressively regulated by thyroid hormone and the decrease in thyroid hormone level in the diabetic state affects the levels of CYP4A2 and P450 K-2.

Complete cDNA sequence and cDNA-directed expression of CYP4A11, a fatty acid omega-hydroxylase expressed in human kidney

A cDNA was isolated from a human kidney lambda gt10 library using the rat CYP4A3 cDNA as a probe. The cDNA-deduced amino acid sequence encoded a protein of 519 amino acids that was designated CYP4A11 (Nelson et al., 1993) and exhibited 76%, 72%, 80%, and 53% similarities to rat CYP4A1, rat CYP4A3, rabbit CYP4A6, and human CYP4B1, respectively. The deduced amino-terminal amino acid sequence of this cDNA agreed with the amino-terminal amino acid sequence of a major P450 protein purified from human renal microsomes. A second variant form of CYP4A11 cDNA, designated CYP4A11v, was isolated from the same library and had a deletion of a single adenine residue, thereby extending the reading frame and resulting in a protein of 591 amino acids. CYP4A11v is probably encoded by a rare allelic variant of CYP4A11, since no mutant alleles were uncovered in 15 normal individuals, as determined by a polymerase chain reaction (PCR) diagnostic test. Baculovirus-mediated cDNA expression of CYP4A11 yielded a P450 protein having a lambda max of 452 nm when reduced and complexed with carbon monoxide. The expressed enzyme efficiently catalyzed omega-hydroxylation of lauric acid. No detectable activity was uncovered toward arachidonic acid and prostaglandin E1. The cDNA-expressed variant, CYP4A11v, was found to be unstable and not to efficiently metabolize lauric acid, as assessed by both baculovirus and monkey kidney COS cell cDNA expression systems. These studies indicate that CYP4A11 is a major fatty acid-metabolizing P450 that is expressed in human kidney.

Increased CYP1A2 content and capacity to activate Glu-P-1 and Trp-P-2 in liver microsomes of scorbutic ODS rats

Osteogenic Disorder Shionogi (ODS) rats, which cannot synthesize ascorbic acid due to a deficiency of L-gulonolactone oxidase, become scorbutic when not supplied with dietary ascorbic acid. We used the deficient rats to study the effects of ascorbic acid on the amount of cytochrome P450 enzymes in liver microsomes. The total amount of hepatic cytochrome P450 in ODS rats deprived of ascorbic acid was lower by approximately 40%, whereas ODS rats fed with ascorbic acid and the wild strain had the same level of total hepatic cytochrome P450. Western blot analysis for various forms of cytochrome P450 in liver microsomes indicated that the amount of CYP1A2 was significantly higher in ascorbic acid deficient rats. On the other hand, amounts of CYP2B2 and 3A were lower, and those of CYP2E1 and CYP2C6/11 were unaffected. In accordance with the higher amount of CYP1A2, Northern blot analysis showed increased expression of CYP1A2 mRNA. The capacity of microsomes to produce mutagens from 2-amino-6-methyl-dipyrido[1,2-a:3',2'-d]imidazole acetate (Glu-P-1) and 3-amino-1-methyl-5H-pyrido[4,3-b]indole acetate (Trp-P-2) was higher in scorbutic ODS rats by the Ames test. These results indicate that the effects of ascorbic acid deficiency on the expression of cytochrome P450 in ODS rat livers are form-specific and that the increased CYP1A2 is associated with increased metabolic activation of promutagens in the scorbutic state.

Characterization of two P-450 isozymes placed in the rat CYP2D subfamily

Two P-450s with debrisoquine 4-hydroxylation activity, designated P-450 UT-7 and UT-7b, were purified and partially purified, respectively, from hepatic microsomes of untreated male rats. Both purified P-450s with an apparent molecular weight of 49,000, were associated with another protein with an apparent molecular weight of 29,000 which was designated 29 k-protein. The CO-reduced spectra of both P-450 UT-7 and UT-7b showed a peak at 448 nm. The NH2-terminal amino acid sequences of P-450 UT-7 and UT-7b were the same as the amino acid sequences of CYP2D1 and CYP2D2 deduced from the cDNA, respectively, except for the lack of a terminal methionine for P-450 UT-7b. In a reconstituted systems, P-450 UT-7 and UT-7b catalyzed lidocaine 3-hydroxylation and N-deethylation in the presence of the 29 k-protein. The Km and Vmax values for lidocaine 3-hydroxylation were 3.6 microM and 0.50 nmol/min/nmol of P-450 for P-450 UT-7, and 3.6 microM and 0.93 nmol/min/nmol of P-450 for P-450 UT-7b, respectively. Antibody against P-450 UT-7, which also cross-reacted with P-450 UT-7b, inhibited lidocaine 3-hydroxylation in liver microsomes from untreated male rats, but had little effect on lidocaine N-deethylation. These findings suggested that lidocaine 3-hydroxylation in hepatic microsomes from untreated male rats was catalyzed by P-450 UT-7 and/or UT-7b.P-450 UT-7 not containing 29 k-protein was obtained as the non-absorbed fraction from hydroxylapatite HPLC. The activities of debrisoquine 4-hydroxylation as well as lidocaine 3-hydroxylation and N-deethylation in a reconstituted system with P-450 UT-7 without 29 k-protein were one-fifth of those of P-450 UT-7 containing 29 k-protein at the same substrate concentration. These findings suggested that the 29 k-protein was essential to express the maximal metabolic activities. However, the lidocaine metabolic activity in a reconstituted system with P-450 UT-7 containing 29 k-protein and in hepatic microsomes were not inhibited by 29 k-protein antibody.

Identification of CYP2C23 expressed in rat kidney as an arachidonic acid epoxygenase

A cDNA was isolated from a rat kidney cDNA library using mixed probes of CYP (cytochrome P450) 2C6, 2C7, 2C8, 2C9 and 2C18 cDNAs. The 3'-terminal and 5'-terminal regions of the cDNA were sequenced and were identical with those of cytochrome P450 2C23 (CYP2C23) except for a one-base deletion and a one-base addition in coding region. These changes caused a frame shift and changed the deduced amino acid sequence relative to the previously published sequence. This cDNA was expressed using a baculovirus expression system, and the resultant P450 had a lambda max of 450 nm when reduced and complexed with carbon monoxide. Specific content of the expressed P450 ranged from 0.27 to 0.43 nmol/mg of cell lysate protein. Arachidonic acid metabolism catalyzed by expressed CYP2C23 indicated that CYP2C23 efficiently produced epoxyeicosatrienoic acids (EETs). These EETs were characterized further by gas-liquid chromatography/negative ion chemical ionization mass spectrometry (GC/NCIMS) and were found to include 8,9-EET, 11,12-EET and 14,15-EET in a ratio of 1:2:1. No 5,6-EET was detected. A low rate of lauric acid hydroxylation at the (omega-1)-position was found, but the enzyme was unable to metabolize prostaglandin E1. These studies suggest that CYP2C23 is responsible, in part, for the production of EETs in rat kidney.

[Some problems of TS measurement after administration of fluoropyrimidines in colorectal cancer. Kinki Cooperative Study Group of Chemotherapy for Colorectal Carcinoma]

A joint multicenter comparative study of carmofur (HCFU) alone or HCFU+dipyridamole (DP) concurrent administration was conducted by the Kinki Colorectal Cancer Chemotherapy Society. In this study, the drugs were administered five days prior to surgery, and thymidylate synthetase (TS) inhibition rate at the primary lesion of colorectal cancer was determined. In addition, the effect of time after resection of the primary lesion before specimen cooling on the TS inhibition rate was investigated. The subjects were 87 registered patients who received colorectal cancer surgery during 4 months from October 1991 to January 1992. The time before postsurgical cooling was divided into four group; within 10 min (n = 67), 11-20 min (n = 8), 21-30 min (n = 7), and 31 min or longer (n = 5). The TS inhibition rates (mean +/- SD) were 0.45 +/- 0.22, 0.38 +/- 0.19, 0.30 +/- 0.21, and 0.04 +/- 0.05 respectively. The longer the time after resection of the primary lesion before specimen cooling, the more TS inhibition rate decreased. When the time before specimen cooling exceeds 30 min, the major part of TS combined with FdUMP exists in a free state. Therefore, it was considered not suitable as the material for the measurement.

Mitochondrial NADPH-linked aquacobalamin reductase is distinct from the NADPH-linked enzyme from microsomal membranes in rat liver

Mitochondrial NADPH-linked aquacobalamin reductase was purified and characterized to clarify its enzymatic properties. The enzyme was purified about 360-fold over rat liver mitochondrial membranes in a yield of 7.5%. The purified enzyme was homogenous in SDS-PAGE. The molecular mass (M(r)) of the enzyme was calculated to be 65 kDa by SDS-PAGE and by Toyopearl HW55 gel filtration, indicating that the enzyme is a monomeric polypeptide with M(r) of 65 kDa. The enzyme was a flavoprotein containing 1 mol of FAD and FMN per mole of the enzyme. The enzyme was specific for NADPH as electron donor and had the ability to reduce cytochrome c (15.4 mumol.min-1 x mg protein-1), potassium ferricyanide (4.9 mumol.min-1 x mg protein-1) and 2,6-dichlorophenolindophenol (16.8 mumol.min-1.mg protein-1) as well as aquacobalamin (6.4 mumol.min-1 x mg protein-1). Although the enzyme immunoreacted with an antibody against NADPH-cytochrome P-450 reductase, which had the activity of the NADPH-linked aquacobalamin reductase in rat liver microsomes, the mitochondrial enzyme and the microsomal enzyme had different enzymological properties.

Surgical resection of potentially curable pancreatic cancer with improved preservation of endocrine function--further evaluation of intraoperative cytodiagnosis

Very early detection of pancreas cancer is most desirable, since it permits less invasive surgery which has a correspondingly greater chance of success. The present study investigated both surgical outcome and postsurgical quality of life in 8 patients whose occult neoplasms were successfully treated. In all 8 patients, cytology of the pancreatic secretion obtained during endoscopic retrograde pancreatography (ERP) was positive, although no pancreatic tumor was detected by ERP, other examinations or intraoperative inspection. In these 8 patients, our method of intraoperative cytodiagnosis to locate occult neoplasms of the pancreas (Surgery 1992; 111: 294-300) was used (1). Using this method of cytodiagnosis, we were able to avoid total pancreatectomy in 6 patients (75%; 3 pancreatoduodenectomies and 3 caudal pancreatectomies), but not in the other 2 patients. Histopathological study of the resected specimens indicated that the extent of pancreatic resection was quite appropriate in all 8 patients. There were 6 minimally invasive carcinomas, one carcinoma in situ and one borderline lesion. Neither nodal involvement nor severe invasion was found on microscopic inspection, and all have been disease-free for 23 +/- 13 months after surgery. In the 6 patients with partial pancreatectomies, both postoperative quality of life and general health were good, with no insulin-dependent diabetes developing. Thus, our cytology-guided surgical technique is very useful not only for locating occult and potentially curable neoplasms, but also for avoiding blind resection of the entire pancreas, permitting better preservation of pancreatic endocrine function.

[Changes of serum interleukin 6 (IL6) and acute phase protein after hepatectomy in patients with chronic liver disease]

We examined the changes in serum levels of interleukin 6 (s-IL6) and acute phase protein (APP) during perioperative periods in patients with or without chronic liver disease (CLD) who underwent hepatectomy or other surgeries. The elevation of s-IL6 on the first postoperative day was only correlated with preoperative values of indocyanine green retention test (ICG-R15) (r = 0.56, p < 0.01), and not concerned with any operative factors. We divided the patients into the following three groups; the patients with CLD undergoing hepatectomy (n = 21, group A), the patients without CLD undergoing hepatectomy (n = 7, group B), and the patients without CLD undergoing surgeries other than hepatectomy (n = 7, group C). The values of s-IL6 on preoperative day, 1st, 4th, and 7th days after surgery in group A were significantly higher than the corresponding values in group C (p < 0.05). Among the hepatectomy groups, the serum levels of APP on the 4th day after surgery were significantly higher than those on preoperative day. We concluded that the changes in s-IL6 after hepatectomy were strongly concerned with preoperative liver function, especially with values of ICG-R15. However, it seemed that the induction of APP was negatively correlated with the preoperative liver function.

Clinicopathological features and prognostic significance of nucleoside diphosphate kinase/nm23 gene product in human pancreatic exocrine neoplasms

Expression levels of nucleoside diphosphate (NDP) kinase/nm23 gene product in the surgically resected 59 human pancreatic exocrine neoplasms were examined immunohistochemically using antiNDP kinase antibody. Immunoreactivity for NDP kinase varied from one tumor to the other. Out of the 47 invasive pancreatic duct cell carcinomas examined, 31 (66%) tumors showed strong immunoreactivity for NDP kinase, whereas ten (83%) of 12 benign or less invasive tumors (in situ adenocarcinoma and mucin-producing tumor) showed negative or weak immunoreactivity (p < 0.01; Chi-square test). Overall survival of invasive pancreatic duct cell carcinomas with strong immunoreactivity for NDP kinase was poorer than those with negative or weak immunoreactivity (p < 0.03; generalized Wilcoxon test). Strong immunoreactivity for NDP kinase was associated with the type of histological differentiation, the presence of lymph node metastases (p < 0.05, respectively; Chi-square test), and the number of argyrophilic nucleolar organizer regions (p < 0.01; Student's t-test). These results suggest that NDP kinase/nm23 gene product expression was positively associated with tumor aggressiveness and poor survival of patients in human pancreatic exocrine neoplasms. They also suggest that NDP kinase expression is related to cell proliferation activity represented by the number of argyrophilic nucleolar organizer regions. Therefore, examining the level of NDP kinase/nm23 gene product could serve as a marker for malignant potentiality of pancreatic exocrine neoplasms.

Cytochrome P450 isozymes catalyzing the hepatic microsomal oxidation of 9-anthraldehyde to 9-anthracene carboxylic acid in adult male rats

Microsomal aldehyde oxygenase (MALDO) activity for 9-anthraldehyde (9-AA) was significantly higher in the male than in the female adult rat liver. 9-AA MALDO activity was also significantly enhanced by pretreatment with dexamethasone and phenobarbital, whereas it was not significantly changed by 3-methylcholanthrene or acetone. Several cytochrome P450 isozymes purified from rat hepatic microsomes were able to catalyze the oxidation of 9-AA to 9-anthracene carboxylic acid (9-ACA) in the presence of NADPH, NADPH-cytochrome P450 reductase and dilauroylphosphatidylcholine. Under the ordinary conditions of the reconstituted system, the catalytic activities (nmol/min/nmol P450) of cytochrome P450s, 2A1, 2B2, 2C6, 2C11 and 3A2 were 1.53 (1.37 in the presence of cytochrome b5), 1.20 (2.06), 4.87 (7.75), 18.0 (21.6) and 0.90 (1.17), respectively. Cytochrome P450 2C11 (CYP 2C11) showed the highest catalytic activity of the cytochromes examined. In the reconstituted system using the lipids extracted from microsomes, CYP 3A2 more effectively catalyzed the oxidation of 9-AA to 9-ACA, and its catalytic activity (nmol/min/nmol P450) was 3.33 or 6.61 in the absence or presence of cytochrome b5, respectively. The antibody against CYP 2C11 inhibited by 90% the hepatic microsomal oxidation of 9-AA MALDO activity in adult male rats, but the activity was not inhibited by antibody against CYP 3A2. These results show that the individual forms of cytochrome P450 have a catalytic activity for the oxidation of 9-AA to 9-ACA, and that CYP 2C11 is the major constitutive catalyst of 9-AA MALDO activity in untreated adult male rat liver.

Purification and characterization of a form of P450 from horse liver microsomes

A form of P450 [termed P450(h-1)] was purified from the liver microsomes of a male horse to electrophoretic homogeneity. The specific content of the final P450(h-1) preparation was 14.8 nmol/mg of protein and the recovery was 0.38% of the microsomal P450. The apparent molecular weight of P450(h-1) was 52,000 Da. The absorption spectra of P450(h-1) indicated that P450(h-1) was a low- and high-spin mixed type P450 in the oxidized form. The reconstituted system containing P450(h-1) could catalyze benzphetamine N-demethylation, 7-ethoxycoumarin O-deethylation, and testosterone 16 alpha-hydroxylation. In the horse hepatic microsomes, aniline p-hydroxylation and testosterone 6 beta-hydroxylation, in addition to the above reactions, were detected. The N-terminal amino acid sequence of P450(h-1) was highly homologous to that of rat P450 2C11. Western blot analysis using anti-P450(h-1) antibody revealed that this antibody most strongly recognized P450 2C13 among ten rat P450s belonging to eight different subfamilies involved in hepatic drug metabolism. This anti-P450(h-1) antibody inhibited the testosterone 16 alpha-hydroxylase activity in horse liver microsomes. These results suggest that P450(h-1) belongs to the P450 2C subfamily and contributes to the testosterone 16 alpha-hydroxylation in horse liver microsomes.

[Survey for primary tumor site in patients with initial clinical presentation of bone metastasis]

Among the patients who were examined with bone scintigraphy between April 1985 and March 1991, there were 27 patients whose initial clinical manifestation was bone metastasis and who were surveyed for the primary tumor site. The primary tumor site could be identified in 20 patients (74%), consisting of 9 patients with lung cancer, 3 with prostate cancer, 3 with hepatoma, 2 with renal cancer, and one each with thyroid cancer, adrenal cancer, and pleural malignant mesothelioma. In 17 of the 20 patients, the primary site had been detected within two months after presentation. Examinations which were helpful in identifying the primary site included chest radiography, sputum cytology, abdominal sonography, serum prostatic acid phosphatase level and pathologic examination of biopsy specimens. 99mTc-PMT scintigraphy was useful in the diagnosis of the hepatoma when accumulation was observed at the metastatic sites. In 2 patients, lung cancer had been recognized using follow-up chest radiography 3 and 6 months after presentation, respectively. One patient was diagnosed at autopsy as having adrenal cancer. In 7 patients the primary site remains unknown. Histology examination of the biopsy specimen performed in 6 of these patients revealed 4 to be adenocarcinoma and 2 undifferentiated carcinoma. The average survival period of the 17 patients who died was 9.5 months. Four patients are alive, and the outcome in the remaining 6 could not be determined.

Clonal analysis of fibroadenoma and phyllodes tumor of the breast

Clonality of fibroadenoma and phyllodes tumor of the breast was analyzed by means of the polymerase chain reaction using small DNA samples prepared from cryostat sections. The method of clonal analysis was based on restriction fragment length polymorphism of X-chromosome-linked phosphoglycerokinase gene and on differential methylation of the gene. Specimens from 10 fibroadenomas and 5 phyllodes tumors heterozygous for the BstXI polymorphism of PGK gene were subjected to clonal analysis. It was found that fibroadenoma was polyclonal, but phyllodes tumor was made up of both monoclonal and polyclonal cell components. Since these tumors contained both epithelial and stromal components, clonality of each component was analyzed separately. Analysis of clonality of each cell component showed that both the epithelial and stromal cells were polyclonal in fibroadenoma and that the epithelial cells were polyclonal, but the stromal cells were monoclonal in phyllodes tumor. When DNA samples were prepared from widely separated sites of phyllodes tumors, every sample was found to contain a monoclonal stromal cell component. These results demonstrate that fibroadenoma is a hyperplastic lesion rather than a neoplasm, and that phyllodes tumor is a neoplasm of the stromal cells.

Changes in amounts of cytochrome P450 isozymes and levels of catalytic activities in hepatic and renal microsomes of rats with streptozocin-induced diabetes

Hepatic microsomal cytochrome P450s, which are involved in the metabolism of drugs, hormones, prostaglandins and fatty acids, change when animals develop diabetes. We studied changes in cytochrome P450 isozymes in both hepatic and renal microsomes of rats with diabetes caused by streptozocin, and compared the results with changes in catalytic activities in the microsomes. In hepatic microsomes of diabetic rats, the amount of cytochrome P450 2E1, an acetone-inducible isozyme, was two and a half times that of control rats, and that of P450 4A2, a major renal isozyme, was three times that in the controls. The amounts of cytochrome P450s 2A1, 2C6, 2C7, 3A2 and 4A3 increased in hepatic microsomes of diabetic rats, and P450 2C11 decreased. Treatment with insulin restored these to the levels in the controls. The catalytic activities of aniline hydroxylation, 7-ethoxycoumarin O-dealkylation, testosterone 2 beta, 6 beta, 7 alpha, and 16 beta-hydroxylation, and omega-, (omega-1)-hydroxylation of lauric acid were high in the hepatic microsomes of diabetic rats, and testosterone 2 alpha and 16 alpha-hydroxylation activities were low. In renal microsomes of diabetic rats, cytochrome P450s 2E1, 4A2 and K-4 were induced, and omega- and (omega-1)-hydroxylation activities were high. These changes were reversed by insulin treatment. The induction and suppression of cytochrome P450 isozymes in diabetic rats were consistent with the changes in the catalytic activities. In both hepatic and renal microsomes, P450s 2E1 and 4A2 were induced, altered metabolism of ketones and fatty acids in diabetes may contribute to these changes.

Increased expression of sialyl Lewisx antigen correlates with poor survival in patients with colorectal carcinoma: clinicopathological and immunohistochemical study

We have previously shown that sialyl Lewisx antigen (sLex) (NeuAc alpha 2-3Gal beta 1-4(Fuc alpha 1-3)GlcNAC-R) has an important functional role in defining the invasion and metastasis of human colorectal carcinoma. The results were derived from the clinical specimens obtained at surgery or experimental metastasis of human colon carcinoma variant expressing different levels of sLex in nude mice. In the present study, we immunohistochemically examined 132 human colorectal carcinomas for the expression of sLex to investigate whether this antigen expression could serve as a prognostic parameter. The tumors were divided into two groups: sLex positive and sLex negative. The incidence of sLex positive was correlated with the depth of tumor invasion, the presence of the lymph node metastasis, lymphatic invasion, and the disease stage. The difference was statistically significant (P = 0.0026; P = 0.0002; P = 0.003; P = 0.0013; respectively). Based on the data on 114 patients who underwent curative resections, incidence of the disease recurrence was assessed. The sLex-positive patients had higher incidence of recurrence in distant organs, especially in the liver, than that of the sLex-negative patients. The 5-year disease free survival rates of sLex-positive and -negative patients were 57.7 and 89.1%, respectively (P = 0.0002). The difference of 5-year overall survival rates between the two were also significant (sLex positive, 58.3%; sLex negative, 93.0%: P < 0.0001). By Cox multivariate analysis, sLex expression levels remained the best discriminant of disease-free survival (P = 0.035) and overall survival (P = 0.0081). These results suggest that increased expression of sLex is correlated with the extent of malignancy and high incidence of recurrence and consequently with survival of colorectal carcinoma patients. Thus sLex may prove to be a potent marker of recurrence in colorectal carcinoma patients.

[Evaluation of intra-arterial infusion chemotherapy and radical pancreatectomy in patients with locally advanced pancreatic cancer]

This is a retrospective study to evaluate arterial infusion chemotherapy and resection for locally advanced pancreatic cancer involving retro-peritoneal organs or large vessels such as superior mesenteric artery or celiac trunks. Intra-arterial chemotherapy was performed for 19 patients, and 15 underwent pancreatectomy. Patients in the intra-arterial chemotherapy group could live 11 months out of the hospital, against 4 months in the resected cases (p < 0.05). The period of over 2nd degree in performance status was 11 months in the arterial chemotherapy group and 3 months in resected groups (p < 0.05). The survival rates were 53, 18 and 9% at 1, 2 and 3 years in the patients with arterial chemotherapy, respectively, against 22, 15 and 15% in the resected patients (p < 0.05). These results suggested that intra-arterial chemotherapy was significantly effective in prolonging the survival period with a better quality of life.

Magnetic resonance imaging-histologic correlation of small hepatocellular carcinomas adenomatous hyperplasias

RATIONALE AND OBJECTIVES

Hepatocellular carcinomas (HCCs) usually consist of components of different histologic grade. Using surgically resected specimens, the authors obtained high-resolution magnetic resonance (MR) images and studied the relationship between histologic grade of HCCs and MR signal intensity.

METHOD

In vitro MRI was performed on 15 small (less than 20-mm diameter) HCCs and 2 patients with adenomatous hyperplasia (AH) within 1 hour of surgical resection. In these 17 lesions, 24 macroscopic nodular components corresponding to MR images were recognized pathologically. The difference in MR signal intensity was examined by using tumor/phantom (T/P) signal-intensity ratio. In addition, the correlations between signal intensity on MRI and histologic criteria for grading HCC were studied.

RESULTS

On T2-weighted images, grade II HCCs had significantly greater T/P values than grade I HCCs (P < .01). There is the correlation (r = .88, P < .001) between nucleocytoplasmic (N/C) ratio and signal intensity of small HCCs and AHs on T2-weighted images.

CONCLUSION

The N/C ratio is an important factor relating the signal intensity to the histologic grade of these lesions on T2-weighted images.

Palliative surgical treatment for recurrent and non-resectable hepatocellular carcinoma

Of 275 patients who had a radical hepatic resection for HCC, 143 (52%) experienced recurrences. Of these 143 patients, the liver was the site of first recurrence in 130 patients (91%). The first form of therapy for recurrent patients was transarterial chemoembolization (TACE) in 82 (74%), hepatic resection in 15 (14%) and percutaneous ethanol injection in 6 (5%) of the 111 patients who received regional therapy. Post-recurrent survival rates of TACE and hepatic resection were 37%, 77% at 3 years and 17%, 77% at 5 years, respectively. Wrapping therapy was performed in seven patients, two of whom had received repeat TACE for intrahepatic recurrence; the remaining 5 were unresectable cases. After wrapping therapy, the area of previous collateral feeders was be supplied by the hepatic artery. The high level of AFP decreased dramatically. This procedure resulted in a complete response in 2 patients, a partial response in 3 and no change in 2. Overall survival was 4-54 months, and the median survival was 18 months. Two patients are still alive, 18 and 20 months after the procedure.

["Partial wrapping therapy" for recurrent hepatocellular carcinoma by transthoracic route]

Two patients with recurrent hepatocellular carcinoma close to the diaphragma, underwent TAE following decollateralization using silicone rubber sheeting with thoracotomy. The patients suffered from severe liver cirrhosis. Laparotomy was not carried out for the preservation of hepatic function. After wrapping therapy, serum AFP level was reduced to almost the normal range in one case, but in another case to half because of bilateral lung metastasis. The maximum serum level of postoperative serum total bilirubin in these 2 cases was 2.0 mg/dl and 1.6 mg/dl, respectively. We think wrapping therapy with thoracotomy is readily applicable for patients with severe cirrhosis.

[Composite resection of sciatic nerve for local recurrence of rectal cancer]

Three patients with local recurrence of rectal cancer involving the sciatic nerve underwent radical pelvic exenteration combined with sciatic nerve resection. This surgical procedure resulted in complete relief of intolerable cancer pain in all patients. After the rehabilitation, all could walk unassisted by wearing only a below-the-knee leg brace. The first patient died 16 months postoperatively due to multiple liver metastasis, but no local recurrence was documented. The second patient is alive 13 months postoperatively with bone and liver metastasis and pelvic wall recurrence. The third patient is alive 7 months postoperatively with no evidence of disease. Composite resection of lateral sciatic nerve improved the quality of life in patients who had local recurrence of rectal cancer with sciatic nerve involvement.

[Significance of preoperative TAE as an adjuvant therapy for hepatocellular carcinoma]

In 304 patients with hepatocellular carcinoma who underwent hepatic resection, 162 patients received chemoembolization before surgery (group A) and the remaining 142 patients received no therapy before surgery (group B). The 5-year disease-free survival (DFS) of group A and B were 36% and 21%, respectively, and there were no significant differences between them. In the groups of patients with good liver function (Child A), or patients with solitary tumor, or patients with tumors more than 5 cm in size, DFSs of group A were significantly better than those of group B. The difference of DFS between group A and B was largest in the group of the patients with tumors more than 5 cm in size.

Down-regulation of transforming growth factor-alpha by tamoxifen in human breast cancer

BACKGROUND

The influence of tamoxifen treatment on transforming growth factor-alpha (TGF-alpha) levels in human breast cancer rarely has been studied in vivo.

METHODS

Postmenopausal patients with estrogen receptor (ER)-positive and progesterone receptor (PR)-positive primary breast cancer underwent two fine-needle aspiration biopsies (FNA) of the tumors. Between the two FNAs, 10 patients received no treatment (control group), and the other 10 patients received tamoxifen (20 mg/day) for 10 (8-12) days (TAM group). TGF-alpha levels in FNA samples were assayed by enzyme immunoassay.

RESULTS

No significant difference was found in TGF-alpha levels between the first and second FNA samples in the control group. On the other hand, in the TAM group, TGF-alpha levels in the second FNA samples (2.5 +/- 0.5; mean +/- SEM ng/mg.DNA) were significantly (P < 0.01) lower than those in the first (4.5 +/- 0.8). Studies on the influence of tamoxifen treatment on TGF-alpha levels in ER-negative and PR-negative breast cancer showed that TGF-alpha levels were not affected by tamoxifen treatment. Positivity of epidermal growth factor receptor (EGFR) was 60% in ER-negative and PR-negative breast cancer and 30% in ER-positive and PR-positive breast cancer.

CONCLUSIONS

Tamoxifen downregulates TGF-alpha levels in ER-positive and PR-positive breast cancers through ER. The significance of TGF-alpha as an autocrine growth factor appears to be more important in ER-negative and PR-negative breast cancer with high EGFR positivity than in ER-positive and PR-positive breast cancer with low EGFR positivity.

Changes in the amounts of cytochromes P450 in rat hepatic microsomes produced by cyclosporin A

1. The effect of cyclosporin A, an immunosuppressive drug, on the levels of individual cytochromes P450 of rat liver was studied by immunoblotting with specific antibodies. Changes in the metabolic activities of the microsomal enzymes were similarly studied. 2. Total P450 was decreased by treatment with cyclosporin A for 17 days. NADPH-P450 reductase activity was also decreased by treatment with cyclosporin A for 10 days and decreased further after 17 days. 3. Cytochromes 2B2 and 2C6 concentrations were decreased by treatment with cyclosporin A for 17 and 10 days, respectively. Administration of cyclosporin A for 17 days also decreased the levels of the male specific cytochromes 2C11 and 3A2, and consequently decreased testosterone 2 alpha-, 16 alpha-, 2 beta- and 6 beta-hydroxylation activities. Shorter periods (7 and 10 days) of cyclosporin A treatment decreased the level of cytochrome 3A2, which metabolizes cyclosporin A. In contrast, the level of cytochrome 2C13 was unchanged.

Delayed washout of intratumor blood flow is associated with good response to intraarterial chemoembolization for liver metastasis of colorectal cancer

BACKGROUND

We studied stagnation of the blood in hepatic metastatic lesions of colorectal cancer.

METHODS

Twenty-two hepatic tumors in 11 patients with liver metastases of colorectal cancers were investigated in this study. With a catheter inserted into the roots of the proper hepatic artery, 5 to 10 mCi 133Xe was injected. The half-time (t1/2) was calculated for the tumor region based on the washout curve by the compartmental method and expressed as the intratumor retention time of the blood.

RESULTS

Transcatheter arterial chemoembolization with iodized oil (Lipiodol) and cisplatin was effective in eight (50%) of 16 tumors that were hypervascular but in only one (17%) of six tumors that were hypovascular (p < 0.05). Regardless of the hypervascular tumor, transcatheter arterial chemoembolization was not effective in tumors that had shown a t1/2 of less than 80 seconds. Seven of eight good-responding lesions that were hypervascular and had a long t1/2 (187 +/- 74.6 seconds) revealed characteristic fireworks-shaped accumulation of Lipiodol.

CONCLUSIONS

Transarterial infusion chemotherapy for liver metastasis of colorectal cancer was considered effective for hypervascular hepatic tumors with a long t1/2.