Clonal analysis of regenerative nodules in hepatitis C virus-induced liver cirrhosis

BACKGROUND/AIMS

Based on histological criteria, regenerative nodules in cirrhotic liver have been generally considered to result from hyperplastic proliferation of hepatocytes. Whether these nodules are hyperplastic or neoplastic has not been determined definitively. This study examined the issue by clonal analysis of each nodule.

METHODS

The method for clonal analysis was based on restriction fragment length polymorphism of the X chromosome-linked phosphoglycerokinase gene and on random inactivation of the gene by methylation.

RESULTS

Clonality of hepatocellular carcinoma (n = 7) and regenerative nodules (n = 76) induced by hepatitis C virus infection was analyzed. All carcinomas were monoclonal. Clonal analysis of regenerative nodules showed that 43% (33 of 76) were monoclonal in origin. Adjacent monoclonal nodules showed inactivation of the same allele of phosphoglycerokinase gene. Because the gene allele is inactivated at random, it is unlikely that each nodule happens to inactivate the same allele; it is more likely that monoclonal cell expansion is initiated before the nodule is established by septum formation.

CONCLUSIONS

Monoclonal cell expansion is seen in a considerable number of regenerative nodules in cirrhotic liver. The results indicate that certain genetic changes, which are required for hepatocarcinogenesis, have already occurred in these nodules.

Induction of cytochrome P450 isozymes in rat renal microsomes by cyclosporin A

To examine the effects of cyclosporin A (CsA) on renal cytochrome P450 forms, CsA was administered to rats, and the renal levels of P450 were determined by immunoblotting. CsA treatment for 17 days increased total renal P450 content by 40% with a concomitant elevation of the omega- and (omega-1)-hydroxylation activities of lauric acid. Arachidonic acid omega-hydroxylation activity was also induced 2-fold by treatment with CsA for 17 days. Among the P450 forms, CYP4A2 was induced significantly, whereas CYP2C23, CYP4A1 and CYP4A8 were unaffected. These changes were accompanied by slight but significant increases in blood urea nitrogen and systolic blood pressure. These data suggest that CsA increased arachidonic acid omega-hydroxylation activity by the induction of CYP4A2. The specific induction of CYP4A2 may be related to CsA-induced nephrotoxicity and elevated blood pressure, because omega-hydroxyarachidonic acid is a potent vasoconstrictor.

Liver perfusion chemotherapy via both the hepatic artery and portal vein to prevent hepatic metastasis after extended pancreatectomy for adenocarcinoma of the pancreas

Since hepatic metastasis is a common cause of treatment failure after curative pancreatectomy for adenocarcinoma of the pancreas, we developed a new method of postoperative hepatic perfusion chemotherapy via both the hepatic artery and portal vein. The present study was conducted to determine if this method decreases the hepatic recurrence and improves the survival rate. Following extended pancreatectomy with wide lymphatic and connective tissue clearance for pancreatic cancer, one catheter was placed in the hepatic artery and one in the portal vein. Immediately after surgery, 5-fluorouracil (125 mg/d) was continuously infused via these two routes simultaneously for 28 to 35 days. There were no treatment-related complications in the 20 patients who survived surgery. The 3-year survival rate was 54%, and the cumulative rate of death from hepatic metastasis was 8%. These figures were significantly better than those of our historical control groups. We conclude that this method should be evaluated in a prospective, randomized controlled study.

Is the long-term survival rate improved by preoperative irradiation prior to Whipple's procedure for adenocarcinoma of the pancreatic head?

OBJECTIVE

To determine whether or not both regional control and long-term survival rate were improved by preoperative irradiation prior to curative pancreatectomy for adenocarcinoma of the pancreatic head.

DESIGN

Retrospective study of recorded medical data from 1985 to 1989.

SETTING

The Center for Adult Diseases, Osaka, one of the major cancer centers in Japan.

PATIENTS AND INTERVENTION

Fifty-four consecutive patients in whom pancreatic head cancer had been judged to be resectable by preoperative diagnostic techniques. A total of 50 Gy per 10 MeV of x-ray was irradiated preoperatively to the wide field, including the pancreatic head area, in 23 patients (group A) but not in the 31 remaining patients (group B). The background factors before treatment did not differ between these two groups.

OUTCOME MEASURES

Resectability, postoperative survival, and modes of cancer recurrence.

RESULTS

At laparotomy, curative pancreatectomy was possible in 17 patients (74%) in group A and 19 (61%) in group B (not significant). In patients undergoing resection, the 1-year survival rate was 75% in group A and 43% in group B (P < .05). However, 3- and 5-year survival rates were almost the same in both groups (28% vs 32% and 22% vs 26%, respectively). With regard to the cause of death after pancreatectomy, group A had a significantly lower incidence of deaths due to regional recurrence within 1.5 postoperative years compared with group B, whereas deaths due to hepatic metastasis were markedly higher after 1 postoperative year in group A compared with group B.

CONCLUSIONS

Preoperative irradiation prior to pancreatectomy succeeded in reducing the incidence of early deaths due to regional recurrence. However, owing to the next barrier--death due to hepatic metastasis after 1 postoperative year--long-term (3- and 5-year) survival rate was not improved at all.

Expression of autocrine motility factor receptor in colorectal cancer as a predictor for disease recurrence

BACKGROUND

New biologic prognostic factors are needed to guide the treatment of patients with colorectal cancer. The prognostic value of the altered expression of the cell surface glycoprotein gp78, which has been implicated in tumor-cell invasion and metastasis as an autocrine motility factor (AMF) receptor, was evaluated.

METHODS

The level of expression of AMF receptor gp78 was analyzed immunohistochemically in tumor specimens from 118 patients who had undergone surgery for colorectal cancer. Multivariate analysis was used to determine whether gp78 expression status was correlated with patient prognosis.

RESULTS

Among the 118 patients studied, the 5-year survival rate for the 51 patients who had gp78-positive tumors was significantly poorer that that of the 67 patients who had gp78-negative tumors (49.8% vs. 89%). The incidence of gp78 positivity was correlated with tumor progression as reflected by histologic type, depth of invasion, lymph node metastasis, vessel invasion, and tumor stage. Among the 101 patients who underwent curative resection, the difference in disease free survival between patients with gp78-positive tumors and those with gp78-negative tumors was significant. This significant difference remained among patients who had Stage II tumors. Multivariate analysis with the Cox regression model indicated that gp78 positivity was a good predictor of disease recurrence, ranking with extent of tumor invasion (T classification) and lymph node status (N classification).

CONCLUSIONS

Increased expression of gp78 is correlated with a high incidence of recurrence and, consequently, with decreased survival of patients with colorectal cancer. Expression of gp78 might be of prognostic value in these patients.

The prognostic significance of surgical margin in liver resection of patients with hepatocellular carcinoma

OBJECTIVE

To evaluate the prognostic significance of surgical margin in liver resection of patients with hepatocellular carcinoma.

DESIGN

Retrospective study.

SETTING

The Center for Adult Diseases, Osaka, Japan, between 1980 and 1989.

PATIENTS

One hundred eighty-five patients with hepatocellular carcinoma who underwent liver resection with complete extirpation.

MAIN OUTCOME MEASURE

Cumulative survival rate.

RESULTS

The patients were divided into a wide surgical margin group, in which the lesion was excised with a margin of 1.0 cm or more, and a narrow surgical margin group, in which the margin was less than 1.0 cm. No significant differences could be detected in survival rates for 3 years or longer. Mean +/- SE tumor sizes were 3.4 +/- 0.4 cm and 4.4 +/- 0.3 cm, respectively, in the wide and narrow surgical margin groups. The patients were divided into three groups according to tumor size: group 1, 2.0 cm or less in diameter; group 2, greater than 2.0 cm but 5.0 cm or less in diameter; and group 3, greater than 5.0 cm in diameter. In groups 2 and 3, no significant differences in survival rates were found between the wide and narrow surgical margin groups. In group 1, the survival rate was significantly higher in the wide surgical margin group than in the narrow surgical margin group (P < .05).

CONCLUSIONS

Small hepatocellular carcinomas of 2.0 cm or less in diameter should be resected with an adequate surgical margin. However, surgical margin was not a significant factor in the resection of hepatocellular carcinomas larger than 2.0 cm.

[A case of huge liver metastasis from jejunal leiomyosarcoma completely controlled by intra-arterial and intra-portal vein infusion chemotherapy following hepatectomy]

A 39-year-old woman was found to have intrapelvic tumor and multiple liver metastases by abdominal computed tomography. Although laparotomy was done under the diagnosis of ovarian cancer with liver metastases, the histological diagnosis of the tumor during the operation was jejunal leiomyosarcoma. Only the primary lesion was removed at the same time. Three weeks later, right lobectomy of the liver and catheterization of the hepatic artery and the portal vein were carried out for liver metastases. Following the procedure, intra-arterial and intra-portal vein infusion chemotherapy of epirubicin was performed every 2 weeks. The patient has been well for 1 year and 11 months with complete remission.

["Wrapping therapy" for hepatocellular carcinomas with collateral feeders]

A new treatment method to intercept collaterals with silicone rubber sheeting, called "wrapping therapy", was used for 18 patients with advanced hepatocellular carcinomas having collateral feeders from other organs surrounding the liver. Chemoembolization in 17 of the 18 patients in whom it had been conducted more than once, had proven ineffective. Obvious collateral feeders (parasitic branches) to the tumors were recognized on hepatic angiograms in two-thirds of the patients. This procedure was followed by regional chemotherapy and/or chemoembolization. The 3- and 4-year survival rates of the patients after "wrapping therapy" were 54% and 54%, respectively. This therapy is worth using for hepatocellular carcinomas uncontrolled by arterial therapy because of development of collateral feeders.

The detection of breast carcinoma micrometastases in axillary lymph nodes by means of reverse transcriptase-polymerase chain reaction

BACKGROUND

The development of a sensitive method for the detection of breast carcinoma micrometastases in axillary lymph nodes is reported.

METHODS

The method was based on amplification of MUC1 mRNA, which encodes a core protein of polymorphic epithelial mucin, by a reverse transcriptase-polymerase chain reaction (RT-PCR). Total RNA, which was extracted from a breast carcinoma cell line (MCF-7), primary breast carcinomas, and axillary lymph nodes, was subjected to analysis of MUC1 mRNA expression by the RT-PCR method.

RESULTS

MUC1 mRNA expression was detected by RT-PCR in MCF-7 cells and in all 15 primary breast carcinomas but not in control lymph nodes taken from patients with benign diseases. A serial dilution study revealed that MUC1 RT-PCR was a very sensitive method, detecting one MCF-7 cell per 1,000,000 lymph node cells. The detection sensitivity of MUC1 RT-PCR method was compared with that of immunohistochemical staining of an epithelial marker (polymorphic epithelial mucin). Fifty axillary lymph nodes were obtained from 15 patients with primary breast carcinomas, and metastasis in each lymph node was investigated by both methods. The immunohistochemical method demonstrated metastasis in nine lymph nodes, and MUC1 mRNA was detected in all of them. Of the 41 lymph nodes that were diagnosed to be devoid of metastasis by immunohistochemistry, MUC1 mRNA was expressed by 6 but not by the other 35, indicating the presence of micrometastases in these 6 lymph nodes that could be detected only by the MUC1 RT-PCR method.

CONCLUSIONS

The MUC1 RT-PCR method is more sensitive than immunohistochemistry for the detection of micrometastases in axillary lymph nodes. This new method would be of practical value in selecting the patients at high risk for relapse from those who are histologically lymph node negative.

[Promotion of hematogenous metastasis in relation to endothelial cell injury by treatment with anticancer drugs]

It has been reported that anticancer drugs at high concentration increase experimental hematogenous metastasis owing to endothelial injury. In this study, we evaluate the effects of anticancer drugs at clinical doses on endothelial cells in the process of metastasis. To do so, we have developed in vitro assay methods which can assess endothelial cell retraction and barrier function against invasion by tumor cells. 5-FU at clinical doses caused neither retraction nor decreasing barrier function, however, ADR and MMC caused retraction of endothelial cells and increased invasion by tumor cells. These effects reached maximum 12 hours after treatment with ADR or MMC, and the number of liver metastases was also significantly increased in in vivo study when tumor cells were injected via portal vein at 12 hours after administration of ADR. It was suggested that some kinds of anticancer drugs at the clinical dose may increase hematogenous metastasis in treatments.

[A case of hepatocellular carcinoma implantation to chest wall by percutaneous ethanol injection therapy]

A 62-year-old male patient with hepatocellular carcinoma (HCC) received percutaneous ethanol injection therapy (PEIT) four times following fine needle biopsy (FNB). Six months later, he underwent partial hepatic resection because of the insufficient anti-cancer effect of PEIT. One year and five months after PEIT, a subcutaneous tumor, which appeared to be a needle tract seeding by PEIT, was recognized in the 9th intercostal space of the right chest wall. A curative resection of the partial chest wall, including IXth and Xth ribs, was carried out with reconstruction using dexon mesh five months later. The tumor was 3.5 cm in size, and the histology was moderately-differentiated HCC. PEIT is a useful treatment for small HCCs. When PEIT is carried out, due care should be taken for neoplastic needle-tract seedings as one of the possible complications.

Changes in content of P450 isozymes in hepatic and renal microsomes of the male rat treated with cis-diamminedichloroplatinum

1. The changes in the activity of drug-metabolizing enzymes and in the content of P450 isozymes in renal and hepatic microsomes after treatment of the male Sprague-Dawley rat with cis-diamminedichloroplatinum (Cisplatin, CDDP) were examined. 2. NADPH-P450 reductase activity in renal microsomes was significantly increased by treatment with CDDP, but lauric acid omega- and (omega-1)-hydroxylation activities of renal microsomes were not increased. 3. The level of P4502C23 was increased significantly and levels of P4504A2 and 4A8 tended to increase in renal microsomes. 4. In hepatic microsomes, lauric acid omega-hydroxylation activity was increased, but (omega-1)-hydroxylation activity was not. Levels of P4502C11 and 3A2, which are male-specific forms, were decreased, whereas levels of P4502A1, 2C7 and 2E1 were increased in hepatic microsomes. The levels of P4504A2 and 4A3 were increased by CDDP and the level of P4504A1 was not changed. Changes in the protein levels of P450 by CDDP were consistent with those in the mRNA levels reported previously (LeBlanc et al. 1992). 5. Male-specific forms in rat liver such as P4502C11 were decreased by CDDP, but those in the kidney such as P4504A2 was not. Therefore, CDDP has different influences on the regulation of hepatic and renal P450s.

[Adjuvant chemo-endocrine chemotherapy with gastrin antagonist after resection of liver metastasis in colorectal cancer]

This study was designed to determine whether or not chemo-endocrine therapy after the resection of liver metastasis from colorectal cancer would prevent re-recurrence in the liver. Postoperatively, seven patients received proglumide gastrin antagonist (1,200 mg/day) +5'-DFUR (800 mg/day) orally for 2 years. MMC 6-10 mg and ADR 20 mg were infused every two weeks alternately for 1 year via catheter in the common hepatic artery. After median follow-up of 39 months, re-recurrence rate in the remnant liver after hepatic resection was 14% (1/7) for patients with chemo-endocrine therapy and 52% (24/46) for the controls. These results suggest the possibility that chemo-endocrine therapy is effective to prevent re-recurrence of liver metastasis in patients with colorectal cancer.

Necrosis of hepatocellular carcinoma caused by spontaneously arising arterial thrombus

This paper describes a 65-year-old Japanese man with hepatocellular carcinoma (HCC) in whom the alpha-fetoprotein level decreased remarkably without any treatment. Plain computed tomography disclosed a low-density area in the left lateral segment. Liver scintigraphy revealed a filling defect with 99mTc-Sn colloid and increased uptake of 67Ga-citrate. The latter was smaller in area than the former. This indicates that non-necrotic HCC was still present at this time. There was no hypervascular lesion in the hepatic angiogram obtained 22 days after liver scintigraphy. The tumor was resected by partial hepatectomy 24 days after hepatic angiography. The histological section showed almost complete necrotization of the tumor, and the necrotic change consisted of old and recent necrosis. An arterial thrombus was formed in non-tumor liver tissue. It was presumed that coagulative necrosis was produced by interruption of the blood supply due to the spontaneous formation of an arterial thrombus.

Discrimination between multicentric and multifocal carcinomas of the breast through clonal analysis

BACKGROUND

An unanswered, important question concerning multiple breast carcinomas is whether they arise independently in the breast (multicentric) or are metastatic deposits from a single, primary carcinoma (multifocal). This issue was studied by clonal analysis of each focus of multiple breast carcinomas.

METHODS

First, the clonality of 30 breast carcinomas was analyzed by the method based on restriction fragment length polymorphism of the X-chromosome-linked phosphoglycerokinase (PGK) gene and on random inactivation of the gene. Second, the clonality of each focus of three multiple breast carcinomas was analyzed by the same method.

RESULTS

Clonal analysis of the 30 breast carcinomas revealed that every carcinoma was monoclonal in origin, and one of two alleles of the PGK gene was inactivated at random in these carcinomas. Three patients with multiple breast carcinomas had three, three, and four histologically separate foci of carcinoma in the breast, respectively. Clonal analysis showed that each focus was monoclonal in origin and, in addition, the same allele of the PGK gene was inactivated consistently at each focus in every patient.

CONCLUSIONS

The thesis that multiple carcinoma foci arise independently is unlikely to be true, because the probability that every independent focus happens to inactivate the same allele of PGK gene in every patient is very low. It seems more likely that a single primary carcinoma spreads throughout the breast to culminate in multiple secondary carcinoma foci. Therefore, it is concluded that multiple breast carcinomas are multifocal and not multicentric in origin.

Clonal analysis of solitary intraductal papilloma of the breast by means of polymerase chain reaction

Clonality of solitary intraductal papillomas of the breast was analyzed using a method based on restriction fragment length polymorphism of the X-chromosome-linked phosphoglycerokinase (PGK) gene and on random inactivation of the gene by methylation. The application of polymerase chain reaction to this method enabled clonal analysis of such a small intraductal lesion as papilloma. Clonal analysis of DNA samples obtained from the nine solitary intraductal papillomas and adjacent normal breast tissues showed that all of the papillomas were monoclonal and all the normal breast tissues were polyclonal in origin. When DNA samples were obtained from four widely separated sites in the papillomas, clonal analysis showed that all were monoclonal and, in addition, the same allele of PGK gene was inactivated in each case. These results demonstrate that solitary intraductal papilloma arises as a single monoclonal tumor and extends along the ducts rather than occurring as multicentric monoclonal tumors and merging together subsequently. Immunohistochemical staining of smooth muscle alpha-actin, a marker protein of myoepithelial cells, revealed that solitary intraductal papilloma was composed of approximately equal mixtures of luminal epithelial and myoepithelial cells. Since solitary intraductal papillomas were shown to be monoclonal in origin, it was suggested that this disease originates from a common precursor that could differentiate into both luminal epithelial and myoepithelial cells.

Analysis of factors affecting uptake of Tc-99m Sn-N-pyridoxyl-5-methyltryptophan by hepatocellular carcinoma

We performed Tc-99m PMT imaging in 176 patients with HCC and evaluated factors affecting 99mTc-PMT uptake by HCC with a logistic model. The probability of HCC showing increase in uptake of the radioisotope was 104.6 times higher in patients with the Ed I type than in those with the Ed III type and 12.1 times higher in patients with a tumor diameter of 5.0-7.9 cm than in those with a tumor diameter of 2.0-5.0 cm. Among the other variables, the serum AFP level and sex were suggested to have effects similar to those of the tumor size on Tc-99m PMT uptake by HCC. The grade of morphological differentiation of the tumor was therefore most markedly related to Tc-99m PMT uptake.

Surgical treatment of adrenal metastasis following pulmonary resection for lung cancer: comparison of adrenalectomy with palliative therapy

Although adrenal metastases from lung cancer are frequently detected during the late clinical stage or at autopsy, they are rarely surgically treated following pulmonary resection for lung cancer. We detected adrenal lesions as initial clinical recurrence in 9 (1%) of 904 patients who underwent pulmonary resection for lung cancer at our institute between 1980 and 1992. Adrenalectomy was performed in five who had developed unilateral adrenal metastasis. One underwent simultaneous operation for primary and metastatic lesions, and 4 underwent adrenal surgery following pulmonary resection. The adrenal tumor was removed via laparotomy in three patients, and via posterolateral non laparotomic approach in two. Co-metastatic lesions which were detected incidentally at operation included intestinal metastasis in two patients and regional lymph node metastasis in two; these were simultaneously resected. Following adrenalectomy, all these patients were treated with adjuvant chemotherapy or radiotherapy. Two patients have remained free of relapse for 40 and 26 months, respectively, after adrenal surgery, while three died of other distant metastases more than 9 months after adrenalectomy. In contrast, the four patients who received chemotherapy or radiation therapy died less than 6 months after palliative therapy. Thus, we consider that surgical treatment for adrenal metastases following pulmonary resection for lung cancer is effective in selected cases. The indications for adrenalectomy are presented in comparison with those for palliative therapy, and several difficulties in the surgical management of adrenal metastases are discussed.

Clonal analysis of predominantly intraductal carcinoma and precancerous lesions of the breast by means of polymerase chain reaction

Clonality of predominantly intraductal carcinoma (PIC) and precancerous lesions of the breast was analyzed by a method based on restriction fragment length polymorphism of the X-chromosome-linked phosphoglycerokinase gene and on random inactivation of the gene by methylation. The application of polymerase chain reaction to this method enabled clonal analysis of small lesions. In order to eliminate the contamination by normal stromal cells, intraductal components were microdissected from the frozen sections of PIC under a dissection microscope. Clonal analysis of the intraductal components from seven PICs revealed that all were monoclonal in origin. In three PICs with intraductal spreading of carcinoma cells over nearly a whole breast gland, the intraductal components were collected from eight widely separated sites in each case. Clonal analysis of these samples showed that every sample was monoclonal and the same allele of the phosphoglycerokinase gene was consistently inactivated in each case. These results suggest that PIC arises as a single monoclonal carcinoma and spreads through the ducts over the gland rather than having multicentric origins. Clonality of precancerous lesions such as atypical ductal hyperplasia and intraductal papilloma arising in the terminal ducts was also studied. Intraductal components were microdissected from the paraffin sections of these lesions and subjected to clonal analysis. Both atypical ductal hyperplasia and intraductal papilloma were found to be monoclonal in origin, suggesting that certain genetic changes had already occurred in the precancerous lesions. A further study is needed to elucidate these genetic changes, which would greatly help our understanding of the mechanism of carcinogenesis.

Clonal analysis of parathyroid adenomas by means of the polymerase chain reaction

Clonality of parathyroid adenomas and normal parathyroid glands was analyzed by a method based on restriction fragment length polymorphism of the X-chromosome-linked phosphoglycerokinase (PGK) gene and on random inactivation of the gene by methylation. Through the introduction of the polymerase chain reaction to this method, clonal analysis could be performed on small DNA samples prepared from cryostat sections of these specimens. Every normal parathyroid gland was found to be polyclonal while every parathyroid adenoma was found to be monoclonal. When DNA samples obtained from four widely separated sites of an adenoma were independently analyzed, each sample was found to be monoclonal and, in addition, the same allele of PGK gene was inactivated. These results suggest that parathyroid adenoma, which has a single cell origin, is a true neoplasm and that its pathogenesis is probably different from that of parathyroid hyperplasia which is polyclonal in origin.

Differentiation of primary and secondary breast cancer with clonal analysis

BACKGROUND

It is often difficult to draw a firm conclusion as to whether the second breast cancer is primary or secondary (metastasis from the initial breast cancer) in a patient with metachronous bilateral breast cancer. In this study we have applied clonal analysis of breast cancer to distinguish whether the second breast cancer is primary or secondary.

METHODS

A 54-year-old woman underwent modified radical mastectomy of the right breast as a result of breast cancer. Five years later she had tumors in the right chest wall and left breast. Fine-needle aspiration cytologic examination revealed that both tumors were adenocarcinoma. To elucidate the origin of these tumors, clonal analysis was done on DNA samples prepared from cryostat sections of the initial right breast cancer and from fine-needle aspirates of the tumors in the right chest wall and left breast. The method for clonal analysis was based on restriction fragment length polymorphism of X chromosome-linked phosphoglycerokinase gene and on differential methylation of the gene caused by random inactivation of one of two X chromosomes.

RESULTS

Clonal analysis revealed that clonal origin of the right breast cancer was different from that of the left breast cancer and identical to that of the chest wall tumor. Therefore it was concluded that the left breast cancer was primary and the chest wall tumor was concluded that the left breast cancer was primary and the chest wall tumor was a recurrence of the initial breast cancer.

CONCLUSIONS

Clonal analysis appears to be a useful method in discriminating a primary from a secondary cancer.

Apoptosis of acinar cells in the pancreas of rats fed on a copper-depleted diet

Male Fischer 344 rats weighing 80-90 g were fed on a copper-depleted diet supplemented with 0.6% triethylenetetramine tetrahydrochloride (a copper chelator), and the death of pancreatic acinar cells of these rats was investigated morphologically and biochemically. The weight of the pancreas of these rats decreased from 3 weeks after feeding, and concomitantly the percentage of dead acinar cells increased to the maximum in about the 5th week and decreased subsequently. These dead acinar cells showed light microscopic and electron microscopic characteristics of apoptosis. Furthermore, the electrophoretic pattern of DNAs extracted from the pancreas having many dead acinar cells showed a ladder-like distribution, characteristic of apoptosis. The present results indicate that feeding of rats on a copper-depleted diet supplemented with a copper chelator results in apoptosis of acinar cells of the pancreas.

Trimethadione metabolism, a useful indicator for assessing hepatic drug-oxidizing capacity

The metabolism of trimethadione (TMO), a useful indicator of hepatic drug-oxidizing capacity in rats and humans, was studied using 14 different forms of rat cytochrome P450 (CYP1A1, 1A2, 2A1, 2A2, 2B1, 2B2, 2C6, 2C7, 2C11, 2C12, 2C13, 2E1, 3A2 and 4A2) and three forms of human cytochrome P450 (CYP1A2, 2C and 3A4). TMO N-demethylation was increased by treating rats with phenobarbital. CYP2C11 and 2B1 had high TMO N-demethylase activity, but 1A1 and 1A2 had low activity. Antibodies raised to CYP2C11 and 2B1/2 inhibited TMO N-demethylation in hepatic microsomes of untreated and phenobarbital-treated rats, respectively. In a reconstituted system, human CYP3A4 and 2C produced efficiently dimethadione (DMO), but CYP1A2 did not catalyse TMO N-demethylation. Antibodies raised to CYP3A2 and 2C11 inhibited TMO N-demethylation in human hepatic microsomes. These results indicated that the N-demethylation of TMO is catalysed mainly by CYP2C11 and 2B1 in rat hepatic microsomes, and that human CYP3A4 and an unspecified isoform of the 2C subfamilies contribute to TMO N-demethylation in human liver.

Gastric cancer in young adults: growth accelerating effect of pregnancy and delivery

The relationship between pregnancy and/or delivery (p&d) and the stage of gastric cancer was studied in 64 female and 57 male patients aged 34 or younger with gastric cancer. Gastric cancer diagnosed within 2 years after p&d (group A, 20 patients) was more progressive (unresectable in 20%) than those of the other young female patients with children (group B, 24 patients; 5%) or without children (group C, 20; 0%), or young male patients (group D, 57; 3%) (P < 0.05). The 5-year survival rate in group A (60.0%) was lower than in group B (83.3%) and group C (85.0%) (P < 0.05 between groups A and B). There were no differences in the duration from the onset of subjective symptoms to diagnosis in the four groups. Out of eight patients who were pregnant after gastrectomy for stomach cancer, one died from recurrence immediately after abortion. These results suggest that pregnancy and/or delivery in young females accelerates the growth of stomach cancer.