C-erbB-2 or mutant Ha-ras induced malignant transformation of immortalized human ovarian surface epithelial cells in vitro

Ovarian cancer is believed to develop from the ovarian surface epithelium through the accumulation of aberrations of oncogenes and/or tumor suppressor genes. However, it is unclear how the gene abnormalities are involved in ovarian carcinogenesis. To elucidate the process, we transfected genes reported to show their abnormalities in human ovarian cancers into human ovarian surface epithelial cells. Immortalization of the cells was achieved by the transfection of SV40 large T antigen (LT) and human telomerase reverse transcriptase (hTERT); however, the resultant cells showed no tumorigenesis. Additional transfection of either c-erbB-2 or mutant Ha-ras into the immortalized cells showed the anchorage-independent growth and tumorigenesis in mice with the incidence of 50% and 40%, respectively. Histologically, all the tumours were undifferentiated. In association with the tumorigenesis, the cells expressing c-erbB-2 or mutant Ha-ras demonstrated increased vascular endothelial growth factor secretion under hypoxia and enhanced resistance to apoptosis compared with the immortalized cells. Collectively, the introduction of either c-erbB-2 or mutant Ha-ras in the cells, which were efficiently immortalized by the transfection of LT and hTERT, showed tumorigenicity, suggesting that c-erbB-2 or mutant Ha-ras genes might be involved in ovarian carcinogenesis.

Visual deprivation stimulates the exchange of the fibrous sclera into the cartilaginous sclera in chicks

Form deprivation myopia in chicks is a widely accepted model to study visually-regulated postnatal ocular growth. The chick sclera has a cartilaginous layer as well as the fibrous layer found in mammals. It appears that a dynamic relationship exists between these two layers during visual deprivation-induced growth. The changes in the fibrous sclera of myopic eyes, however, have not been previously described. This investigation is focused on the comparative morphological analyses of the cartilaginous and fibrous scleral changes in myopic chick eyes. The fibrous scleral changes in the posterior segment of myopic eyes were examined in detail using light and electron microscopy, and the expression of growth factors was analysed by immunohistochemistry. In the posterior segment of myopic eyes the border between the cartilaginous and fibrous layers was indistinct because of collagen bundles of the fibrous sclera that spread into the cartilaginous sclera, whereas in control eyes the distinction was clear. Various types of transitional cells, from fibroblast-like mesenchymal cells to chondrocytes, were found in the border between the cartilaginous and fibrous layers. Collagen fibrillar diameters of the fibrous sclera in the posterior segment of myopic eyes were smaller than in control, whereas those in the equatorial segment were almost the same in myopic and control eyes although the distribution of sizes was obviously different. Thus, changes in the fibrous sclera in myopic eyes of chicks seem to be similar to scleral changes in myopic eyes of mammals. The cells in the posterior sclera of myopic eyes were more intensely immunostained for TGF-beta and IGF-II than control, whereas no immunoreaction of TGF-alpha could be detected in either control or myopic eyes. These results suggest that the structural characteristics of the posterior sclera are different from those of the anterior and equatorial segments. Undifferentiated mesenchymal cells might be concentrically distributed exclusively in the innermost layer of posterior fibrous sclera. TGF-beta and IGF-II might influence cell growth, differentiation, and migration in the exaggerated scleral growth accompanying myopia.

Krukenberg tumor from an occult appendiceal adenocarcinoid: a case report and review of the literature

Appendiceal neoplasms with ovarian metastasis are rare. A 35-year-old woman with a left ovarian tumor underwent left salpingo-oophorectomy, partial resection of the right ovary, and a total hysterectomy. Pathological diagnosis of both ovaries was typical, Krukenberg tumor with signet-ring cells, and the second laparotomy revealed an occult appendiceal tumor to be the primary lesion. The appendix showed no evidence of malignant change of the mucosa, but the tumor cells were observed infiltrating from the basiglandular region into the underlying stroma, associated with mucocele. Although, argentaffin and argyrophil staining were negative, a few tumor cells showed immunohistochemical positivity for Chromogranin A. Accordingly, the tumor was diagnosed as adenocarcinoid rather than adenocarcinoma of the appendix. A review of the literature showed less than 40 cases of metastatic ovarian tumor from appendiceal primary, one-third of which were occult and could be detected at the second laparotomy. Cisplatin-based chemotherapy may have partial effect in the treatment of patient with adenocarcinoid tumor.

Combination effect of adenovirus-mediated pro-apoptotic bax gene transfer with cisplatin or paclitaxel treatment in ovarian cancer cell lines

To develop a novel therapeutic strategy for ovarian cancer, we constructed a recombinant adenovirus which highly expresses pro-apoptotic Bax protein and examined its therapeutic effect on a series of ovarian cancer cell lines: A2780, A2780/cDDP, OVCAR-3 and SK-OV-3. A recombinant adenovirus carrying the Bax-alpha gene (AxCALNKYbax) induced high expression of the Bax-alpha protein in all the cell lines. The cytotoxic effect of Bax was observed in three ovarian cancer cell lines: the per cent reduction in the number of cells was 40.0% for cisplatin-sensitive A2780, 50.0% for cisplatin-resistant A2780/cDDP, and 64.8% for marginally cisplatin-resistant OVCAR-3. In contrast, it was only 12.3% for cisplatin-resistant SK-OV-3. Cisplatin-resistant A2780/cDDP had a p53 mutation and exhibited attenuated Bax induction after cisplatin treatment, which may explain why supplementation of Bax was effective in this chemoresistant ovarian cancer. Combination with cisplatin or paclitaxel enhanced the cytotoxic effect of Bax induction in all but one cell line including cisplatin-resistant A2780/cDDP. It appears that adenovirus-mediated Bax induction, with or without combination with conventional chemotherapy, useful strategy for the treatment of ovarian cancer.

Human ovarian surface epithelial (OSE) cells express LH/hCG receptors, and hCG inhibits apoptosis of OSE cells via up-regulation of insulin-like growth factor-1

Gonadotropins including luteinizing hormone (LH) or human chorionic gonadotropin (hCG) have been implicated as playing an important role in the development of epithelial ovarian carcinomas, most of which are believed to originate from the ovarian surface epithelium (OSE). To address this issue, we examined the expression of LH/hCG receptors and the influence of hCG on cell proliferation and on the apoptosis of cultured human OSE cells. RT-PCR and binding assay revealed that OSE cells express the LH/hCG receptor mRNA and have specific binding activity for hCG. Treatment with hCG stimulated the proliferation of OSE cells in a dose-dependent manner. In addition, hCG treatment inhibited the apoptosis of OSE cells induced by serum deprivation. Among the apoptosis-related genes, hCG treatment did not change the mRNA levels of bcl-2, bax and IGF-1 receptor but significantly increased that of IGF-1. Treatment with IGF-1 alone also suppressed the apoptosis of OSE cells, and treatment by hCG along with neutralization antibody against IGF-1 receptor reversed the anti-apoptotic effect of hCG. Accordingly, LH/hCG signaling followed by up-regulation of IGF-1 is involved in the inhibition of apoptosis of OSE cells, the possible histogenetic origin of epithelial ovarian carcinomas.

Preferential changes in hepatosplanchnic hemodynamics in patients with borderline hypertension

To investigate changes in systemic and regional hemodynamics during the development of human hypertension, we simultaneously measured cardiac index (CI) by the indocyanine green (ICG) dye dilution method, hepatosplanchnic blood flow (HBF) by the ICG clearance method using a two-compartment model, and renal blood flow (RBF) by the p-aminohippurate clearance method in patients with borderline and essential hypertension. In patients with borderline hypertension (BH, n = 27), HBF (435 +/- 15 ml/min/m2) and HBF/CI (16 +/- 1%) were significantly (p < 0.05) lower than in age-matched normotensive controls (528 +/- 21 and 19 +/- 1, respectively, n = 21), while CI, RBF and RBF/CI were similar. In patients with essential hypertension (EH, n = 32), HBF, RBF, and RBF/CI were all significantly (p < 0.01) lower than in the control subjects. Hepatosplanchnic vascular resistance (HVR) in patients with BH was preferentially increased, while total peripheral resistance (TPR) and renal vascular resistance (RVR) remained in the normal range. In patients with EH, TPR, HVR, and RVR were all increased. These results indicate that hemodynamic changes in patients with BH do not occur uniformly among the various regional circulations and suggest that hemodynamic changes in the hepatosplanchnic region precede those in other organ circulations during the development of human hypertension.

Regional scleral changes in form-deprivation myopia in chicks

Similar neurochemical events appear to be involved in the development of myopia in chicks and mammals. The rapid post-hatching development of the chick is ideal for studying experimental myopia. In this investigation, one eye of 2-day-old chicks was deprived of form vision for 2 weeks and then compared to the fellow, non-deprived eye by immunohistochemistry and light and electron microscopy. All deprived eyes showed a high refractive error and ocular enlargement. In deprived eyes, the posterior cartilaginous sclera was thicker and the fibrous sclera of the same section was thinner than the control. Scleral morphological changes were restricted to a central button 6-7 mm in diameter (the posterior pole) within the posterior hemisphere, further divided into posterotemporal and posteronasal parts. The most enlarged, posterior cartilaginous structure of deprived sclera could be divided into an inner and an outer zone. The inner zone had many unevenly-arranged chondrocytes, each having a well-developed granular endoplasmic reticulum and Golgi complex and a very irregular cell surface. Numerous S-phase cells and isogenous groups were detected in the outer zone. Hypertrophic chondrocytes were often observed in the innermost region of the outer zone and the outermost region of the inner zone. The boundary between the outer fibrous sclera and the cartilaginous sclera was irregular and obscured in myopic eyes. Spindle-shaped chondrocytes were seen to be in contact with each other. Thick collagen fibrils, usually seen only in the outer fibrous sclera, were present among the chondrocytes. Results of this morphological study suggest an increased proliferation of chondrocytes and active synthesis of extracellular matrix in visually deprived eyes. The elongation of the ocular axis that accompanies myopia is caused primarily by an active remodeling and differentiation in a restricted section of the posterior scleral cartilage. These facts indicate the posterior scleral cartilage may be more immature than cartilage in anterior and lateral segments.

Two cases of malignant pheochromocytoma treated with cyclophosphamide, vincristine and dacarbazine in a combined chemotherapy

Two patients with malignant pheochromocytoma were treated with a combination chemotherapy regimen consisting of cyclophosphamide vincristine, and dacarbazine (CVD). With the first few cycles of the treatment, one patient, a 29-year-old man had a marked improvement of clinical symptoms and decreases in tumor size and catecholamine levels in plasma and urine. He had been in a clinically stable condition for 18 months but died 34 months after starting of this treatment because the CVD regimen became ineffective and rapid growth of the metastatic tumors occurred. The other patient, a 35-year-old man showed no significant change in tumor size but decreases in hormonal levels in response to CVD regimen. The patient has been in clinically stable condition in a follow-up of 24 months. The combined chemotherapy with CVD appears to be effective for advanced malignant pheochromocytoma.

Expression of class II MHC molecules in the rat pineal gland during development and effects of treatment with carbon tetrachloride

Cells expressing major histocompatibility complex (MHC) class II (Ia) antigen have been examined during the development of rat pineals and in the pineal gland of adult rats treated with carbon tetrachloride. Cells positive for MHC class II are first detected in the pineal gland of the 7-day-old rat. These positive cells increase in number gradually during development, MHC class II immunoreactivity reaching adult levels at 4 weeks after birth. The MHC class II antigen is intensely labeled on the cell surface, and labeled cells are distributed throughout the organ, several positive cells being gathered into groups. The positive cells are small (7-12 microm in diameter), irregular in shape, and frequently exhibit one or more processes. At the electron-microscopic level, the cytoplasm of positive cells contains few organelles, variously sized empty vacuoles, and a few electron-dense lysosome-like structures. Pinealocytes with synaptic ribbons have been found adjacent to immunoreactive cells. Double-immunoperoxidase staining for MRC OX6, MRC OX42, and ED1 results in OX6(-)/ED1(+)/OX42(+), OX6(-)/ED1(-)/OX42(+), and OX6(+)/ED1(-)/OX42(- )cells. These findings suggest that OX6-positive cells in the pineal can be considered as peripheral dendritic cells. The number of cells expressing MHC class II (Ia) antigen significantly increases in the pineal gland of rats after treatment with carbon tetrachloride (P<0.005). Our results indicate that at least some of the OX6-positive cells migrate into the gland from the circulation under these conditions.

Two cases of pheochromocytoma diagnosed histopathologically as mixed neuroendocrine-neural tumor

We treated two rare cases of pheochromocytoma which were histopathologically diagnosed as mixed neuroendocrine-neural tumor (MNNT): a 35-year-old male patient associated with ganglioneuroblastoma and cutaneous neurofibromatosis and a 42-year-old male patient with ganglioneuroma. Both patients showed typical clinical manifestations of pheochromocytoma without any familial traits. Although each of the diseases has its own entity and clinical features, these tumors are all derived from the neural crest tissues. The tumorigenesis of MNNT is still unknown. Here, a brief review of the recent literature on this subject is discussed.

Plasma free dopamine: physiological variability and pathophysiological significance

Dopamine (DA) is the most abundant catecholamines in human plasma and exists mostly in the sulfo-conjugated form (DA sulfate), a biologically inactive metabolite. The paucity of unconjugated DA (PDA) in plasma throws doubt on its physiological significance. However, PDA, when measured with a highly sensitive radioenzymatic method, showed quite different features from norepinephrine and epinephrine in some types of clinical hypertension, lower in essential hypertension and higher in primary aldosteronism and pheochromocytoma. There was a weak but significant correlation between the values of PDA and DA sulfate measured in the same specimens, but DA sulfate was more susceptible to impaired renal function. Upright posture, high salt diets and an intravenous injection of metoclopramide (MCP, 10 mg), a DA receptor antagonist, induced a slight but significant increase in PDA in normal and hypertensive subjects. An intravenous dexamethasone (2 mg) caused a gradual increase in PDA over 150 min after medication, which was completely blocked by concomitant administration of alpha-methyl-p-tyrosine, a tyrosine hydroxylase inhibitor. The responses of PDA to both high salt diets and MCP were blunted in salt-sensitive patients with uncomplicated essential hypertension. The results suggest that DA is not only a precursor of norepinephrine biosynthesis but also plays an inherent role as an active neurotransmitter in the peripheral sympathoadrenal system, and that PDA is a sensitive marker of peripheral dopaminergic activity, which may operate to modulate the cardiovascular and endocrine functions and participate in the pathogenesis of some types of hypertension.

Effect of dexamethasone on plasma free dopamine: dopaminergic modulation in hypertensive patients

To investigate the peripheral dopaminergic modulation in the pathogenesis of human hypertension, we examined the responses of plasma free dopamine (DA) to dexamethasone (Dx) administration, which is suggested to activate dopaminergic activity. We administered Dx 2 mg intravenously to patients with primary aldosteronism (PA), essential hypertension (EH), and normotensive controls (NT). Plasma free DA was increased significantly in all groups and the responses were more remarkable in PA than in EH and NT. Plasma epinephrine (E) showed a gradual increase while plasma norepinephrine (NE) tended to decrease in all groups. The responses of both plasma DA and E were completely blocked by 250 mg of alpha-methyl-p-tyrosine, a tyrosine hydroxylase (TH) inhibitor, suggesting that Dx may stimulate peripheral dopaminergic activity by increasing catecholamine synthesizing enzyme (probably TH) activities. These data suggest that DA itself plays an inherent role in the sympathoadrenal regulation rather than only as a precursor of NE and that dopaminergic hyperresponses may be involved in the pathophysiology of PA.

Renal dopamine spillover rate using 3H-dopamine radiotracer technique as an index of renal dopaminergic nerve activity

Renal and total dopamine (DA) spillover rates at rest were measured in 25 conscious rabbits with chronically implanted renal vein catheters. Renal DA spillover rate was calculated from veno-arterial difference in plasma free DA concentrations across the kidney corrected by the fractional extraction of infused 3H-DA. Plasma free DA concentrations were 11.0 +/- 2.7 pg/ml in the artery and 14.3 +/- 3.6 in the renal vein. Renal and total DA spillover rates were 0.51 +/- 0.08, 2.61 +/- 0.30 ng/min, respectively, both of which were significantly (p < 0.001) lower than the respective norepinephrine (NE) spillover rates (renal: 16.3 +/- 1.4, total: 39.6 +/- 1.7). The fractional extraction of 3H-DA across the kidney (55 +/- 3%) and the total DA clearance (285 +/- 31 ml/min) were both significantly (p < 0.05) higher than that of 3H-NE (45 +/- 3) and the total NE clearance (198 +/- 9), respectively. The ratio of renal to the total spillover rate of DA (0.23 +/- 0.05) was significantly (p < 0.05) lower than that of NE (0.41 +/- 0.04). These results demonstrate that DA is released into plasma within the kidney and suggest that the measurement of renal DA spillover rate using 3H-DA radiotracer technique is useful to detect resting renal dopaminergic nerve activity.

Removal of maternal antibodies from a woman with repeated fetal loss due to P blood group incompatibility

BACKGROUND

Plasmapheresis is intended to lower plasma antibody levels in women with blood group incompatible pregnancies.

CASE REPORT

Therapeutic specific antibody removal by using antigen-positive red cells was applied to a blood group p pregnant women who had a high titer (128) of IgG anti-PP1Pk and had lost all six previous fetuses in blood group P-incompatible pregnancies. Plasma was taken from the patient with an intermittent-flow cell separator, mixed with a volume of washed and packed P-positive red cells equivalent to one-fifth of the volume of plasma, and incubated for 10 minutes in an ice water bath. The PP1Pk antibodies were removed, and the autologous plasma was transfused. Treatment by specific antibody removal was started in the seventh week of gestation, and performed one to three times a week for a total of 56 times up to the 34th week. The volume of plasma treated was 2.4 L per procedure on average and totaled 135 L. After each treatment, the antibody titer in the patient's plasma usually decreased by 1 log2, and no deleterious effect on the women was noted. The titers of IgG anti-P and anti-Pk were kept between 4 and 16 after the ninth week of gestation. At the end of the 34th week of gestation, a male infant was delivered by cesarean section. The infant did not require an exchange transfusion and is now a healthy 2-year-old boy.

CONCLUSION

This therapeutic method is very useful in the management of fetomaternal P-incompatibility.

Recurrence of nanophthalmic uveal effusion

A patient with nanophthalmic uveal effusion had a recurrence 7 months after the initial sclerectomies and sclerostomies. The effusion was cured by repeating the procedure. Specimens obtained at the first operation showed interlacing collagen lamellae and thin collagen bundles with an electron-dense deposit in the perifibrillar space. Specimens from the second operation showed disarranged collagen bundles with closely packed thin collagen fibrils. Collagen lamellae were not found. The regenerated scleral tissue was thought to interfere with the transscleral outflow and to block the bypass route, thus resulting in the recurrence of uveal effusion.