Differential expression of glutathione S-transferases in germ cell tumors of human testes

Glutathione S-transferase (GST) isoenzymes alfa, mu and pi were assessed by Western blotting in normal testes, seminomas and non-seminomatous germ cell tumors (NSGCTs). GST alfa and mu were strongly expressed in all normal specimens (n = 6), the pi isoform, however, could not or barely be detected. Ten (92%) of 11 seminomas had GST pi and only 2 (16%) showed alfa expression. In contrast, twelve (80%) of 15 NSGCTs showed a significant level of GST alfa and only 2 (13%) had GST pi expression. The absence or paucity of mu isoform was characteristic for all neoplastic testicular tissues. A statistically significant relationship (P = 0.021) could be established between GST alfa and stages of disease, i.e., alfa isoform was prevalent in the later stage (IIB, III) NSGCT tumors. These results suggest that the poor prognosis of the later stage NSGCTs may be due to their high GST alfa content, while the GST pi does not seem to have role in this relation.

Reversible S-nitrosation of creatine kinase by nitric oxide in adult rat ventricular myocytes

We have previously demonstrated that the nitric oxide (NO) donor S-nitroso-N-acetylcysteine (SNAC) reversibly decreases the activity of creatine kinase (CK) in an isolated rat heart preparation, markedly suppressing myocardial contractile responsiveness to an inotropic challenge. We wished to further examine the role of exogenous and endogenous sources of NO species on S-nitrosation of CK and subsequent enzyme activity in adult rat ventricular myocytes (ARVM). Two S-nitrosothiol groups were formed in the CK dimer after nitrosation of rabbit skeletal muscle CK in solution. CK inactivation due to S-nitrosation was time- and concentration-dependent in solution and in ARVM lysate for both NO donors S-nitroso-N-acetylpenicillamine (SNAP) and SNAC, and was rapidly reversible with the sulfhydryl dithiothreitol (DTT). Similarly, SNAC or SNAP dose-dependently decreased CK activity in intact ARVM, which was further attenuated by increasing the metabolic activity of the cells with electrical pacing for 1 h. Co-cultures of ARVM with interleukin 1 beta (IL-1 beta)- and interferon gamma (IFN gamma)-pretreated cardiac microvascular endothelial cells (CMEC) caused no detectable decline in myocyte CK activity. Increasing GSH levels attenuated the decline in myocyte CK activity with SNAC, while decreases in myocyte GSH levels enhanced the inhibitory effect of SNAC on intact myocyte CK activity. These data indicate that the degree of inhibition of cardiac myocyte CK by NO is dependent on the extent of myocyte metabolic activity and the intracellular GSH content.

[A lump in the breast. A rare first symptom of ovarian cancer]

The breast is an uncommon site for metastasis from extramammary primaries. A 43-year-old woman presented with a lump in the left breast. A tumour with atypical microcalcifications was seen on the mammogram. Needle aspiration cytology revealed adenocarcinoma cells. The final histological diagnosis was papillary adenocarcinoma with psammoma bodies, probably secondary to an ovarian carcinoma. A bilateral carcinoma of the ovaries was subsequently diagnosed and treated. A mammary tumour with an atypical growth pattern and the absence of in situ carcinoma should always prompt the pathologist to considering the possibility of a metastatic tumour even though this is a rare occurrence. Earlier recognition of metastatic tumours to the breast may result in initiation of appropriate therapy and will preclude unnecessary surgical procedures.

Do metallothioneins affect the response to treatment in testis cancers?

PURPOSE

Data on the involvement of elevated metallothionein (MT) expression in resistance to some of the commonly used anticancer treatments are scattered and conflicting. This encouraged us to examine further the contribution of metallothionein expression to the development of this resistance phenotype.

PATIENTS AND METHODS

Formalin-fixed, paraffin-embedded blocks of primary untreated germ cell testicular tumor specimens, obtained from 77 patients following radical orchiectomy, were examined for their MT expression using monoclonal antibody and immunohistochemistry. Clinical staging, the chemotherapeutic schedule and evaluation of response to treatment (defining objective response) were performed according to UICC criteria.

RESULTS

All tumor types, including seminomas and nonseminomas, expressed MT, regardless of their histology and clinical stage. The immunoreactivity of MT showed a significant positive correlation with the clinical sensitivity of cancer to antitumor therapy (P = 0.0001).

CONCLUSION

In patients with germ cell testicular tumors, high MT expression, as detected by immunohistochemistry, predicts a better response rate to chemotherapy whereas tumors lacking or demonstrating low MT expression show a worse prognosis. These data do not support the hypothesis that MT overexpression contributes to cisplatinum resistance, at least in this tumor type.

Measurement of renal vein blood flow in rats by high-field magnetic resonance

The aim of the present study was to examine whether magnetic resonance imaging (MRI) based method for non-invasive in vivo measurement of vein blood flow in rats could be used to estimate renal blood flow (RBF). Measurements were performed using a high-field (7 Tesla) MRI scanner with a short echo time phase contrast velocity measurement pulse sequence. The method was evaluated in vitro by flow measurements in an acrylic pipe and in vivo by recording left renal vein blood flow in normal and unilaterally nephrectomized rats. In a subset of animals RBF was measured by a direct method using 14C-tetraethylammoniumbromide. In vitro a high accuracy was found between applied and MRI measured flow rates in the range from 0.5 to 33 ml/min (r = 0.997; P < 0.001). In vivo the MRI measured left renal vein blood flow was 70% higher in unilaterally nephrectomized animals compared to control animals (3.4 +/- 0.4 ml/min/ 100 g body wt vs. 2.0 +/- 0.1 ml/min/100 g body wt, P < 0.001). Direct measurements of RBF revealed comparable values (3.4 +/- 0.3 ml/min/100 g body wt vs. 2.3 +/- 0.4 ml/min/100 g body wt, P = 0.05). In addition, the left kidney volume was recorded by MRI with an increase amounting to 40% (1.18 +/- 0.05 ml vs. 0.84 +/- 0.02 ml; P < 0.001) in the nephrectomized group compared to controls. Finally, a positive correlation was seen between left renal vein blood flow and MRI measured renal volume (r = 0.91; P < 0.001). In summary, MRI is a non-invasive tool by which measurement of renal vein blood flow can be performed, and it is concluded that MRI-based renal vein flow measurements can be used to estimate RBF in small rodents.

Is p53 expression, detected by immunohistochemistry, an important parameter of response to treatment in testis cancer?

BACKGROUND

Several prior studies revealed positive p53 expression via immunohistochemistry (IHC) in a large percentage of germ cell testicular cancers (GCTTs). However, the predicting and prognostic value of this protein remains to be defined. Therefore, the aim of our study was to further clarify the role of p53 protein in GCTTs and to look for correlations between its gene expression and other disease parameters, including histological subtype, stage and clinical resistance sensitivity. Furthermore, we correlated p53 protein expression with that of MDRI gene product protein (Pgp) in order to examine the interrelationship between these two markers.

PATIENTS AND METHODS

77 untreated patients with GCTTs were investigated for their p53 expression using monoclonal antibody and immunohistochemistry in paraffin-embedded specimens. There were 34 patients with stage I, 16 with stage II, 27 with stage III disease.

RESULTS

All tumor types, except differentiated teratomas, were immunoreactive for p53 to a various extent ranging from scarcely positive to homogeneously stained tumor cells. Seminomas (S) and embryonal carcinoma (EC) components showed the most positive nuclear staining. p53 expression showed a significant inverse correlation with the stage of disease (P < 0.0003). There was a significant positive relationship between p53 immunoreactivity and response to treatment (P = 0.0012), i.e. high levels of p53 expression correlated with clinical sensitivity of the tumors to chemotherapy. We could demonstrate a statistically significant opposite relationship between p53 and Pgp immunoreactivity (P < 0.0005).

CONCLUSION

Our results show that p53 status in tumor cells may be a strong determinate of susceptibility to chemotherapy and that p53 overexpression has a favorable prognosis in terms of response to treatment in GCTTs. Moreover, the findings provide clinical evidence for the presense of significant relationship between p53 and MDR1/Pgp immunoreactivity. They also suggest that patients resistant to chemotherapy and lacking p53 expression might benefit from an alternative appropriately designed chemotherapeutic regimen to achieve further successful treatment in GCTTs.

Arthritis in a patient with homozygous familial hypercholesterolemia

Familial hypercholesterolemia is a disorder of lipoprotein metabolism characterized by elevated cholesterol, low-density lipoprotein cholesterol, xanthomas and early onset atherosclerosis. Tendinitis and arthritis have been reported in patients with familial hypercholesterolemia. A report is presented of a 9-year-old girl with an acute arthritic attack who was diagnosed as homozygote familial hypercholesterolemia with hypercholesterolemic arthritis.

REPULSION, A Novel Approach to Efficient Powder Averaging in Solid-State NMR

A novel approach to efficient powder averaging in magnetic resonance is presented. The method relies on a simple numerical procedure which based on a random set of crystallite orientations through simulation of fictive intercrystallite repulsive forces iteratively determines a set of orientations uniformly distributed over the unit sphere. The so-called REPULSION partition scheme is compared to earlier methods with respect to the distribution of crystallite orientations, solid angles, and powder averaging efficiency. It is demonstrated that powder averaging using REPULSION converges faster than previous methods with respect to the number of crystallite orientations involved in the averaging. This feature renders REPULSION particularly attractive for calculation of magic-angle-spinning solid-state NMR spectra using a minimum of crystallite orientations. For numerical simulation of powder spectra, the reduced number of required crystallite orientations translates into shorter computation times and simulations less prone to systematic errors induced by finite sets of nonuniformly distributed crystallite orientations.

[Metallothionein expression as a marker of therapeutic sensitivity in the early stages of testicular cancer]

Data concerning the involvement of elevated metallothionein (MT) expression in drug resistance are obviously scattered and contrasting. The presence of the MT gene product protein was screened in 51 untreated human germ cell testicular tumours, furthermore a relationship between MT expression and clinical resistance was investigated. Using monoclonal antibody and immunoenzyme staining elevated MT level could be demonstrated in nuclei and cytoplasm of both seminomas and non seminomatous germ cell testis tumours. Thirty-one tumours (61%) showed extensive, 15 (29%) focal positive staining. In contrast teratomas expressed this antigen negatively or scarcely. The highest level of MT was stated in early stages (I, IIA) compared with progressed stages (IIB, III) (p = 0.0004). Between the high level of MT and clinical resistance a converse correlation could be shown because the resistant tumours expressed no or low, while the sensitive tumours significantly high level of MT protein which can be used as an useful marker to identify patient subgroups sensitive to anticancer therapy, at least in testis tumours.

Cytobrush and endocervical curettage in the diagnosis of dysplasia and malignancy of the uterine cervix

BACKGROUND

The validity of cytobrush and endocervical curettage combined with colposcopically directed biopsies in the diagnosis of cervical dysplasia and malignancy has not been evaluated in randomized trials. We aimed to elucidate the diagnostic validity of the two methods.

METHODS

A prospective, randomized study of 180 consecutive patients. All patients were examined without anesthesia by colposcopically directed biopsies of the ectocervix and randomly assigned to either cytobrush or endocervical curettage. Patients with < or = CIN 1 were investigated with the alternative method three months later. Patients with > or = CIN 2 had a cone biopsy.

RESULTS

One hundred and thirty-one patients were evaluable. The sensitivity of cytobrush and endocervical curettage combined with colposcopically directed biopsies of the ectocervix was 96% and 84% (p = 0.08), respectively. The specificities of the two investigations were 95% and 88%, respectively (p = 0.78). All cytobrush specimens were evaluable but because of a low recovery of endocervical material a diagnosis could not be made in 12% of the patients examined by endocervical curettage.

CONCLUSION

The sensitivity of the combined use of cytobrush and biopsies of the ectocervix was equal to or higher than the sensitivity of endocervical curettage and ectocervical biopsies. The specificities of the two investigations were much alike. All cytobrush specimens were evaluable but a diagnosis could not be performed in 12% of the endocervical curettage specimens because of too little endocervical material. Furthermore, cytobrush is less inconvenient to the patient. Therefore, in the follow-up of patients with cervical dysplasia endocervical curettage may be replaced with cytobrush.

Multidrug resistance of testis cancers: the study of clinical relevance of P-glycoprotein expression

Germ cell testicular tumors (GCTTs) are very sensitive to anticancer treatment. However some patients ultimately die of their disease due to tumor resistance. Multidrug resistance is mediated by the mdr1 gene product P-glycoprotein (P-gp) which is one important mechanism of drug resistance. This study attempted to examine the correlation between P-gp and tumor progression and to evaluate the clinical relevance of P-gp immunoreactivity in patients with GCTT. Expression of the P-glycoprotein was screened in 48 primary human GCTTs, that have not been treated with chemotherapy, using monoclonal antibody (C219) and immunoenzyme staining. Of the samples from 14 seminomatous germ cell testicular tumors (SGCT, 2 seminomas (14%), and of 34 non-seminomatous tumors (NSGCT) 18 (53%) showed high expression of P-glycoprotein. This difference proved to be significant (P = 0.006). The expression of P-gp showed a statistically significant positive correlation with cancers of advanced stages (P = 0.003) and cancers that showed resistance to chemotherapy (P = 0.0052). Detection of P-gp expression in patients with GCTTs before the application of anti-cancer treatment can be used as a useful prognostic marker to isolate patient subgroups with worse prognosis and less susceptibility to chemotherapy.

Nodular intra-abdominal panniculitis: an accompaniment of colorectal carcinoma and diverticular disease

Intra-abdominal panniculitis is a tumour-like inflammatory condition of adipose tissue. The aetiology and pathogenesis of the disease is unknown, but a number of associated diseases have been recorded. It has been customary to deal with only primary cases in the literature. This study was undertaken in order to describe the entire spectrum of the disease including primary as well as secondary cases. Eleven patients are reported, nine of which had an associated colorectal disease in direct continuity with areas of intra-abdominal panniculitis. It is concluded that intra-abdominal panniculitis should not be regarded as a specific nosological entity but merely a result of injury to the fat cells. Intra-abdominal panniculitis is seen more often as a secondary local phenomenon than as a primary condition, and in both cases it is associated with considerable differential diagnostic problems. Primary diseases involved are, among others, colorectal carcinoma and diverticulosis. The aetiologic agent(s) are still unknown, but substances liberated from a damaged bowel might play a pathogenetic role.

[Correlation between p-53 expression and clinical resistance in testicular cancer]

One of the most common cellular gene which negatively regulates the cell cycle, thus functioning as tumour suppressor gene, is the p-53 gene. The presence of this mutated gene has been correlated with, the aggressiveness of several malignant neoplasmas. Expression of the p-53 gene product protein was screened in 55 untreated human germ cell testicular tumours, furthermore a relationship between p-53 expression and clinical resistance was investigated. Using monoclonal antibody and immunoenzyme staining elevated p-53 level could be demonstrated in nuclei of embryonal carcinoma (84%) and seminoma components (56%). Most of the choriocarcinoma cases showed positive staining. Teratomas expressed this antigen negatively or scarcely. In seminomas the highest level of p-53 was stated in stage I. In contrast the opposite tendency could be demonstrated in embryonal carcinomas where p-53 was ++ positive in stage III. Between the high level of p-53 and clinical resistance a converse correlation could be stated because the resistant tumours expressed no or low, the sensitive tumours high level of p-53 protein (P 0.01). These results suggest that elevated p-53 expression could be a prognostic marker of sensitivity in testis cancer.

[Chronic pancreatitis and upper gastrointestinal hemorrhage]

A 46 year-old woman with a history of chronic pancreatitis, upper epigastric pain and upper gastrointestinal bleeding of obscure origin is presented. A haemoductal pancreatitis was the source of bleeding due to erosion of the splenic artery with bleeding into a pancreatic pseudocyst communicating with the pancreatic duct. This case was special, because there was no aneurysmal dilatation of the splenic artery. This rare entity must always be considered in the diagnosis of gastrointestinal haemorrhage of obscure origin. The appropriate investigation to confirm the diagnosis is visceral angiography, if necessary followed by CT-scan of the abdomen.

Glutathione related enzymes in human testicular germ cell tumors and normal testes

In this study, the activity of the glutathione related enzymes, namely glutathione S-transferase (GST), glutathione reductase (GSSG-R), Selenium-dependent and -independent glutathione peroxidase (GPX) of various TGC tumors (n = 18) obtained from untreated patients, was compared to that of the corresponding enzymes of normal testicular tissues (n = 5). The enzymes of all tumorous tissues except teratomas were significantly less active, than the corresponding enzymes of nontumorous tissues. The GST was in seminomas 4.3-20-, in embryonal carcinomas 47-, and in mixed tumors 13-47-fold less active than in the normal testes. The GST activity of teratomas was about half of that of the normal tissues. The Se-independent GPX, component of GST alfa class, comprised about 90 percent of the total GPX activity in normal testis; however it was absent or barely detectable in all TGC tumors except teratomas. The latter had about the same GPX activity as the tumor-free testicular tissues. Apart from the teratoma, the GSSG-R activity of all TGC tumors was also suppressed to about one third of that of the normal testis. The insufficient function of glutathione related enzymes of TGC tumors may contribute to their sensitivity against treatment. The poorer prognosis of teratomas, however, may be explained by the relatively higher activity of their detoxifying enzymes.

Establishment and characterization of an EBNA-negative human lymphoma cell line (BHL-89)

BACKGROUND

The aim of the work was to establish human malignant lymphomas in culture, in order to study the biological characteristics and drug sensitivity of lymphomas of human lymphoid origin.

MATERIALS AND METHODS

Lymph nodes of patients were explanted and kept in cultures using conventional tissue culture methods. Cytogenetic methods were used for karyotype analysis. Clonogenic assay was applied to test drug sensitivity. The tumorigenic capacity of the cells was determined by inoculating them into immunosuppressed mice. Immunological and other markers were examined with conventional techniques.

RESULTS

A cell line, BHL-89, was established in culture from a patient with B-cell type non-Hodgkin's malignant lymphoma. Cells started to grow after a few days without a feeder layer in stationary suspension. The population doubling time was 48 h. The cells were hyperploid, and non-random aberrations were +1, -15, +14q+. Cloning efficiency in soft agar was found to be as high as 50-60%. The cells expressed markers characteristic of early B cells. The BHL-89 cells were Epstein-Barr nuclear antigen (EBNA) negative. They produced tumors when 10(7) cells were injected into immunosuppressed mice. The cells were sensitive to dibromodulcitol (Elobromol), an alkylating antitumor drug, and resistant to the phorbol ester TPA.

CONCLUSIONS

The established EBNA-negative BHL-89 cell line has a few unique characteristics, e.g. rapid establishment without feeder cells, origin from the lymph node of an adult patient, high clonogenicity in soft agar, and resistance to TPA. The cell line is suitable for studying the nature of B lymphomas and testing compounds against lymphoproliferative disorders.

[Multidrug resistance of testicular cancers. (Detection of P-glycoprotein and MDR1 gene expression and their clinical connection)]

The most frequently reported alteration of multidrug-resistant cells is overexpression of a 170 kD glycoprotein (P-glycoprotein or P-170) encoding by the MDR1 gene family. Expression of the multidrug-resistance gene product P-glycoprotein was screened in 55 untreated human germ cell testicular tumors using monoclonal antibody (C219) and immunoenzyme staining. In samples out of 17 seminomatous germ cell testicular tumors (SGCT) 2 seminomas, and out of 38 non-seminomatous tumors (NSGCT) 20 carcinomas (15 teratomas, 4 embryonal carcinomas, 1 with Yolk sac differentiation and 1 embryonal rhabdomyosarcoma) showed high expression of P-glycoprotein. NSGCT-s, which are more refractory than seminomas to anticancer chemotherapy, frequently expressed P-glycoprotein. These immunohistochemically detected elevated P-170 expressions were correlated by the overexpression of MDR1 mRNA gene sequences. A relationship between clinical resistance and P-glycoprotein expression seems thus to exist in 4 teratomas 3 embryonal carcinomas, and 1 seminomas. A significant correlation (p < 0.02) between P-170 expression and clinical drug resistance in stage II-III germ cell testicular tumors could be demonstrated. The results suggest that a multidrug resistant phenotype may also occur and P-glycoprotein might contribute to drug resistance in testicular tumors.

Renal adaptations to continuous administration of furosemide and bendroflumethiazide in rats

During continuous treatment with diuretics, the kidney adapts to the initial Na loss by activating antinatriuretic mechanisms which serve to prevent further Na and volume losses. To study the renal sites of adaptations to constant diuretic treatment, bendroflumethiazide (4 mg daily), furosemide (8 mg daily) or vehicle (0.24 ml daily) was infused intraperitoneally to female Wistar rats by implanted osmotic minipumps. Half of the animals (groups vol.) were randomized to receive a balanced saline solution to drink in addition to water in order to replace Na, K and volume losses. On the 6th day of treatment, clearances of inulin, Na, and Li were determined during four consecutive 6 hr periods. Circadian changes in renal excretions occurred in all groups with highest excretions of Na, Li and water in the dark period (6 p.m. to 6 a.m.). Renal changes induced by continuous infusion of diuretics were most pronounced in the dark period and would probably not have been disclosed if the clearance experiments had been restricted to the daytime. The average 24-hour clearance for inulin (glomerular filtration rate) was not different among groups, except for a 20% decrease in the furosemide group. The 24-hour fractional Na excretion, being approximately 0.5% in the vehicle group, increased to approximately 0.8% in group (bendroflumethiazide+vol) and to approximately 2.8% in group (furosemide+vol) but was not different from the vehicle group in the diuretic groups without volume replacement.(ABSTRACT TRUNCATED AT 250 WORDS)

Dominant expression of multidrug resistance in intraspecific murine lymphoma hybrid cells

Cultured P388/VCR mouse lymphoma cells resistant to vincristine (VCR) and to 5-bromodeoxyuridine (BUdR) and deficient in thymidine kinase (TK-) were fused with P388/DAG cells resistant to 1.2:5,6-dianhydrogalactitol (DAG), an anticancer alkylating agent, and to 6-thioguanine (6-TG) and deficient in hypoxanthine phosphoribosyl-transferase (HPRT-). The hybrid cells expressed multidrug resistance (MDR), i.e., resistance to VCR and cross-resistance to Adriamycin (ADM) and actinomycin D (Act. D), in a dominant manner. The presence of glycoprotein p170, the MDR gene product, was detected in the hybrid cells. Resistance to DAG was also expressed dominantly, whereas cross-resistance to dibromodulcitol (DBD), a chemically related anticancer drug, was slight.

Thoracic surgery of testicular cancer patients

Between 1 January 1980 and 31 December 1991 the authors treated 1450 patients with malignant testicular tumours. Out of them, in 42 patients aged 18-43 years with stage III non-seminoma germ cell testicular cancer, thoracic surgical interventions took place on 44 occasions since the combined cytostatic treatment did not result in a sufficient regression, or disease progression occurred. In one case the lesion was inoperable. In 43 cases successful resection was performed. In 27 cases unilateral, in two cases bilateral thoracotomy and in 15 cases median sternotomy took place. Solitary lesions were found in 26 and multiple ones in 18 cases, respectively. Two patients died in the direct postoperative phase. Forty patients were followed up for 4 to 130 months. Due to disease progression four and seven patients were lost within 12 and 12-24 months, respectively. Currently, 31 patients are alive 4 to 130 months following surgery (29 of them tumour-free, two with tumour). Based on adequate indications the thoracic surgery is justified both from diagnostic and therapeutic points of view. The metastasectomy might offer an advance in the management of these patients.

Effects of angiotensin-converting enzyme inhibition on renal adaptations to acute furosemide administration in conscious rats

During administration of loop diuretics the initial volume depletion activates Na-conserving mechanisms, which reduces glomerular filtration rate (GFR) and stimulates renal tubular reabsorption of Na and water. By i.v. infusion of the angiotensin-converting enzyme inhibitor enalaprilat (100 micrograms bolus; 100 micrograms/h) we examined the role of angiotensin II for the compensatory renal responses occurring during furosemide administration in conscious rats. To evaluate the significance of hydration for the compensatory renal effects of angiotensin II, experiments were performed in groups of rats with or without i.v. replacement of urinary volume losses. Furosemide was administered i.v. (6 mg/kg/h) for 3 1/2 hr. Furosemide infusion produced a short-lasting increase in urine flow rate, Na, Li and K excretion after which the renal excretion rates returned toward pretreatment levels, along with significant reductions in effective renal plasma flow and GFR and increases in effective filtration fraction and effective renal vascular resistance. Sustained increases in urine flow and urinary excretion rates of Na, Li and K were observed in absence of changes in GFR in rats given furosemide with volume replacement. Enalaprilat did not alter the tubular response to furosemide during either euvolemia or volume depletion. However, enalaprilat attenuated the furosemide-induced increases in effective filtration fraction and effective renal vascular resistance. It is concluded that angiotensin II is not essential for the compensatory response of decreased GFR and increased tubular Na reabsorption. However, angiotensin II is an important mediator of renal vasoconstriction during furosemide infusion.

Predisposition to hypertension: risk factor for nephropathy and hypertension in IDDM

Less than a quarter of the patients with juvenile-onset IDDM develop diabetic nephropathy during the first 20 years of diabetes. To study the determinants of this complication, we selected patients who had come with newly diagnosed IDDM to the Joslin Clinic between 1967 to 1972, and we examined them in 1986 to 1988, that is, 15 to 21 years after onset of diabetes. Using a case control design we compared three groups of cases, that is, advanced nephropathy (N = 43), only microalbuminuria (N = 41), and hypertension alone (N = 17), with a group of controls who remained normoalbuminuric and normotensive despite the long duration of IDDM (N = 61). In comparison with controls, patients with advanced nephropathy had more parents with hypertension (odds ratio 3.8), higher Vmax values of Na/Li countertransport in red blood cells (odds ratio 10.0 for the highest tertile), and higher mean arterial pressure during adolescence and early adulthood (odds ratio 3.1 for those above the median). They also had significantly poorer glycemic control during their first 12 years of diabetes. Patients with hypertension alone were similar to those with advanced nephropathy with regard to markers of predisposition to hypertension but differed from them with regard to glycemic control, having the best glycemic control of all the study groups. Patients who developed only microalbuminuria during 15 to 21 years of IDDM (some of whom will progress to overt proteinuria later) did not differ significantly from controls with regard to predisposition to hypertension. In conclusion, predisposition to hypertension is a major risk factor for the development of advanced diabetic nephropathy and essential hypertension during the first 20 years of IDDM.

Amiloride-sensitive lithium reabsorption during doxazosin-induced blood pressure reduction in rats

1. The effects of acute systemic alpha 1-adrenoceptor blockade by doxazosin on glomerular filtration rate, urine flow, sodium clearance and lithium clearance were investigated in acutely prepared conscious rats. 2. Clearance experiments were performed during water diuresis (20 mmol/l NaCl and 110 mmol/l glucose, 3 ml/h). After a control period, animals were randomized to one of the following treatments: time-control (n = 9), doxazosin (50 micrograms primer, 30 micrograms h-1 kg-1) (n = 10), amiloride (1 mg primer; 2.4 mg h-1 kg-1) (n = 10) and doxazosin plus amiloride (n = 9). 3. Doxazosin reduced the mean arterial blood pressure from 125 to 108 mmHg; this was associated with transient reductions in glomerular filtration rate, urine flow and lithium clearance. After the transient antidiuresis, the sodium excretion rate remained reduced in doxazosin-infused animals. Amiloride increased the sodium excretion rate without having effects on other variables. When doxazosin was given together with amiloride, the reduction in lithium clearance observed during the transient reduction in glomerular filtration rate and urine flow, was partly abolished. Thus the fractional lithium excretion was transiently increased in rats given doxazosin plus amiloride (from 29 to 40%), whereas in rats given doxazosin alone a non-significant reduction was observed (from 28 to 25%). The dissociation between lithium clearance and fractional lithium excretion in the two doxazosin-infused groups was only significant during the transient reduction in glomerular filtration rate and urine flow. 4. The results provide evidence for an amiloride-sensitive lithium reabsorption during acute systemic alpha 1-adrenoceptor blockade.(ABSTRACT TRUNCATED AT 250 WORDS)

[Multidrug resistance of malignant tumors]

The development of resistance to chemotherapy is a major problem in the treatment of malignant tumors. Clinically, this is characterized by short periods of remission and failure to respond to subsequent therapy. Multidrug-resistance or pleiotropic resistance describes the simultaneous expression of cellular resistance to a vide range of structurally unrelated drugs (e.g. alkaloids, anthracyclines, antibiotics, etc.). The most frequently reported alteration of multidrug-resistant cells is the overexpression of a 170 kD glycoprotein (P--170 or P-glycoprotein) encoding by the MDR gene family. A great deal of evidence has suggested that the P-glycoprotein is, in fact, an energy-dependent drug efflux pump. Pharmacological overcome of MDR may indicate to circumvent clinically observed drug resistance.

Genetic analysis of human esophageal tumors from two high incidence geographic areas: frequent p53 base substitutions and absence of ras mutations

Esophageal squamous cell carcinoma (ESC) samples from patients residing in Uruguay and in Normandy, France, where alcoholic beverages and tobacco smoke are major risk factors, were analyzed for point mutations in the p53 tumor suppressor gene. Among 34 tumors (15 from Normandy and 19 from Uruguay) 15 point mutations in the p53 gene that result in amino acid substitutions or chain termination were identified by polymerase chain reaction amplification of exons 5-8 and direct DNA sequencing. Base substitutions in ESC from these high-incidence areas are dispersed over the midregion of the p53 gene. There are differences between ESC and other types of gastrointestinal cancer in the nature of frequent base substitutions. CpG to TpG transitions were far less prevalent in these ESC than in colorectal tumors, whereas G to T transversions, rarely found in colon cancers, were found in one-fourth of the ESC samples. Base substitutions at A:T pairs constitute an important fraction of ESC p53 mutations, in contrast to mutation patterns in most other types of solid tumors. In contrast to the frequent mutation of the p53 gene in these samples, no mutations in the H-, K-, or N-ras genes were found in 16 tumors from Uruguay by direct sequencing of exons in which transforming mutations are known to occur. A previous study on ras mutations in ESC from France was also negative (M. C. Hollstein et al., Cancer Res., 48: 5119-5123, 1988). The role of distinct etiological factors in generating these differences and the potential for linking patient exposure histories with patterns of p53 mutations in high risk populations are considered.

Chromosome number distribution and cellular DNA content in colorectal adenomas from polyposis and nonpolyposis patients

Ploidy analyses of colorectal adenomas were performed by combined flow cytometric DNA analysis of unfixed isolated nuclei and direct chromosome preparation after Colcemid incubation for 9-20 hours. Ten of 18 adenomas from nonpolyposis patients and 4 of 13 adenomas from patients with familial adenomatous polyposis yielded a mean of 25 countable metaphases (range 7-44) per tumor. Of 343 metaphases, only 38% had 46 chromosomes, and 62% were nondiploid. All but one adenoma had diploid or peridiploid modes in the range of 46-50 chromosomes. One adenoma was hyperploid, with a mode of 74 chromosomes and a correspondingly increased nuclear DNA content. In another two adenomas, the DNA analyses showed small hyperploid populations constituting 6% and 2% of the cells. The most striking difference between the DNA analyses and chromosome number distributions was that 13% of all metaphases were hyperploid with chromosome numbers outside the perimodal range but, except in one adenoma, without indication in the DNA histogram of corresponding hyperploid cell populations. We propose that these aberrant metaphases indicate an early acquired genetic instability of the neoplastic epithelium, which may be instrumental in generation of hyperploid, invasive clones, which constitute most colorectal carcinomas.

Suitability of tritiated inulin for determination of glomerular filtration rate

Purity of different batches of [3H]inulin delivered from leading manufacturers was elevated with a chromatographic method (Sephadex G-25 column) that allowed simultaneous analysis of cold inulin, [3H]inulin, and [14C]inulin in the same run. Among four batches of [3H]inulin received within 5 mo, two were found relatively pure, whereas two were partly decomposed to lower-molecular-weight fragments. The chromatographic profile of pure isotopes was not significantly affected by redistribution and freeze drying, nor by subsequent storage in the freeze-dried state at -20 degrees C for up to 5 mo, nor by incubation in aqueous solution at 37 degrees C for 24 h. Three batches of [3H]inulin with different grades of decomposition (noninulin percentages 13%, 38%, and 61%, respectively) were selected for clearance experiments and infused simultaneously with cold and undecomposed [14C]inulin to conscious rats. [14C]inulin had a significantly higher clearance than cold inulin (+7.6 +/- 0.6%) and relatively pure [3H]inulin (+12.4 +/- 0.4%). Decomposed [3H]inulin isotopes progressively underestimated clearance of cold inulin to an extent related to the degree of decomposition. Thus at the end of the 5-h clearance experiment, ratios between clearance of tracer and of cold inulin were 0.92, 0.71, and 0.60 for the three 3H isotopes, respectively. This study indicates that [3H]inulin delivered from leading manufacturers may be decomposed to an extent that invalidates its use as a marker for glomerular filtration rate (GFR). It is thus necessary to check the purity routinely before use. Within the same rat, clearance of undecomposed [3H]inulin and [14C]inulin may differ by 12%, and for this reason they should not be used interchangeably as GFR markers.

Observer reproducibility in grading dysplasia in colorectal adenomas: comparison between two different grading systems

The two most well known and well defined grading systems for dysplasia in colorectal adenomas were compared with regard to reproducibility. The Konishi-Morson system (KMS) operates with several histological and cytological variables and grades of mild, moderate, and severe dysplasia. The Kozuka system is based on the extent of nuclear pseudostratification and also has three grades of dysplasia (III-V). As the group of severe dysplasia is very large in this system, it was extended with two higher grades, similarly based on individual histological criteria, known hereafter as the extended Kozuka system (EKS). Fifty six adenomas were graded by two observers, each observer grading twice according to the KMS criteria and twice according to EKS criteria. Intraobserver reproducibility was excellent for the KMS and moderate for the EKS, but this was not significant. The overall interobserver reproducibility was similar (moderate) for the KMS and for the EKS. Kappa values for interobserver reproducibility on individual categories were excellent for severe dysplasia according to the KMS, but low for all other categories in both systems. By simplifying both systems into two groups a high reproducibility can be obtained, but this implies that all the original grades (III-V) for the EKS must be grouped together. It is therefore recommended that a simplified KMS is used for further studies on the biological importance of dysplasia and for comparison between histological changes and other markers for colorectal neoplasia.

Pleomorphic (giant cell) carcinoma of the intestine. An immunohistochemical and electron microscopic study

Pleomorphic (giant cell) carcinomas have been described in the lungs, thyroid, pancreas, and gallbladder. Two pleomorphic carcinomas of the small bowel and two of the large bowel are presented. On light microscopic study, the carcinomas were solid, without squamous or glandular differentiation. The tumors were composed of the following three cell types: gemistocytic (giant) cells, smaller polygonal cells, and spindle cells, with identical immunohistochemical reactions. A panel of monoclonal and polyclonal antibodies was applied. All tumors were found to coexpress keratin and vimentin. A positive reaction for neuron-specific enolase (NSE) was found in three tumors and a positive reaction for chromogranin was found in one tumor. On electron microscopic study, intracytoplasmic whorls of intermediate filaments were seen in the perinuclear area. Dense core "neurosecretory" granules were rarely seen. Intestinal pleomorphic carcinomas are histologically identical to pulmonary giant cell carcinomas. The prognosis is poor due to early tumor spread, with only a few months of postoperative survival. The pleomorphic carcinomas have some of the differentiation characteristics of carcinoid tumors and are best regarded as poorly differentiated variants of neuroendocrine carcinomas.

Intrinsic and acquired multidrug resistance in human lung carcinomas grown in nude mice

Human epidermoid lung carcinoma xenografts with intrinsic and induced resistance were analyzed with regarding to different parameters. The xenografts with intrinsic resistance to vincristine (HXL 54) and induced drug-resistance sublines to vincristine (HXL 55/VCR), actinomycin D (HXL 55/AD) and cisplatin (HXL 55/DDP) were characterized in terms of the degree of resistance, cross-resistance, proliferation kinetics, tumorigenicity, keratin and P-glycoprotein expression. The results demonstrate that xenografts with intrinsic or induced resistance to vincristine or actinomycin D exhibit a similar general pattern of cross-resistance to that observed in multidrug-resistant cell lines. The resistance cannot be attributed to differences in proliferation kinetics. Development of resistance is associated with loss of tumorigenicity and features of differentiation, P-glycoprotein is little expressed in the resistant xenograft lines and corresponds well with the low grade of resistance.

P-170 glycoprotein, glutathione and associated enzymes in relation to chemoresistance of primary human renal cell carcinomas

High intrinsic chemoresistance contributes to the dismal outcome of patients with disseminated renal cell carcinoma (RCC). In experimental cell lines, two defined defence mechanisms, P-170 glycoprotein and glutathione metabolism, have been established in multidrug resistance, a cross-resistance to cytotoxic compounds without functional or structural similarities. In 21 primary human RCCs, P-170 expression was examined, glutathione content and activities of related enzymes determined and the results were correlated to the degree of in vitro chemoresistance. P-170 was found in 10 of 17 resistant tumors but in none of the sensitive cases. The glutathione content was significantly higher and the related enzyme distinctively enhanced in resistant RCCs. Both mechanisms occurred independently and may well explain the multidrug resistance of RCC. Therefore, reversal of one or both systems may have a clinical impact on the chemotherapy of RCCs.

Detection of drug resistance and P-glycoprotein in human renal cell carcinomas

Expression of the multidrug-resistance gene product P-glycoprotein (P-170) was screened in 21 untreated human renal cell carcinomas using monoclonal antibodies (265/F4, C219) and immunoperoxidase staining. The inherent drug resistance of the same samples against doxorubicin was established by a short-term chemoresistance test in order to investigate the association between the expression of P-170 and intrinsic drug resistance in kidney cancers. P-glycoprotein could be demonstrated in 10 cases. Using the short-term test for predicting resistance, 17 resistant and 4 sensitive cancers were found. In vitro 10 of 17 resistant tumors revealed an increase of P-glycoprotein. On the other hand, in the sensitive tumor in vitro, an expression of P-glycoprotein could not be demonstrated. This investigation reveals that intrinsic drug resistance exists in many renal cell carcinomas and it is associated at least in part with increased expression of P-glycoprotein. The immunohistochemical results suggest that the presence of the P-glycoprotein may be useful as a marker for screening the multidrug-resistant phenotype in renal cell carcinomas and as an indicator of the therapeutic efficacy of multidrug-resistant kidney cancers.

Pleomorphic (giant cell) carcinoma of the intestine. An immunohistochemical and electron microscopic study

Pleomorphic (giant cell) carcinomas have been described in the lungs, thyroid, pancreas, and gallbladder. Two pleomorphic carcinomas of the small bowel and two of the large bowel are presented. On light microscopic study, the carcinomas were solid, without squamous or glandular differentiation. The tumors were composed of the following three cell types: gemistocytic (giant) cells, smaller polygonal cells, and spindle cells, with identical immunohistochemical reactions. A panel of monoclonal and polyclonal antibodies was applied. All tumors were found to coexpress keratin and vimentin. A positive reaction for neuron-specific enolase (NSE) was found in three tumors and a positive reaction for chromogranin was found in one tumor. On electron microscopic study, intracytoplasmic whorls of intermediate filaments were seen in the perinuclear area. Dense core "neurosecretory" granules were rarely seen. Intestinal pleomorphic carcinomas are histologically identical to pulmonary giant cell carcinomas. The prognosis is poor due to early tumor spread, with only a few months of postoperative survival. The pleomorphic carcinomas have some of the differentiation characteristics of carcinoid tumors and are best regarded as poorly differentiated variants of neuroendocrine carcinomas.

Radiosensitivity of drug-resistant human tumour xenografts

The radiosensitivity of three drug-resistant sublines of a human epidermoid lung carcinoma growing as xenografts in nude mice was investigated. Drug resistance to vincristine, actinomycin D and cisplatin was developed in vivo by repeated drug treatment. It was found that all three drug-resistant tumour lines were not cross-resistant to irradiation.

P-glycoprotein expression in treated and untreated human breast cancer

The expression of P-glycoprotein in primary and recurrent human breast cancer was investigated by means of immunohistochemistry, using a monoclonal antibody (C219) and the streptavidin-biotin-peroxidase method. Twelve patients received no chemotherapeutic treatment. The other 11 patients were treated with chemotherapy, and all developed clinical resistance to it. No or only minimal reactivity was found in specimens coming from the untreated patients (12 cases) or from patients treated with substances not involved in the multidrug resistance phenomenon (four cases). In contrast, three out of seven tumours from patients treated with multidrug resistance related substances showed clear reactivity (positive staining in more than 20% of the tumour cells). In one of these cases, where specimens of the tumour could be studied before and after treatment, an association between the latter and expression of P-glycoprotein was suggested. Finally, this marked expression of P-glycoprotein only took place in tumours treated over a longer space of time (five courses or more of multidrug resistance related chemotherapy).

Ultrasonically guided 125iodine seed implantation with external radiation in management of localized prostatic carcinoma

Thirty-three patients with localized prostatic carcinoma (16 poorly differentiated) were treated with transperineal 125Iodine seed implantation (160 Gy) guided by transrectal ultrasonography and subsequent external beam irradiation (47.4 Gy). The observation time was six to sixty-eight months with a median follow-up of thirty-five months. Median change in prostatic volume was a reduction of 35 percent. Re-biopsy or transurethral resection of the prostate was performed in 25 patients after one to two years, revealing still malignant histology in 12 (48%). Development of distant metastases occurred in 14 patients (44%), and 8 have died of prostatic cancer. Fourteen patients suffered from late complications of which surgical intervention was indicated in 3 cases.

[Short-term subcutaneous infusion of insulin using a portable insulin pump in the treatment of diabetes mellitus]

The authors evaluated the effectiveness of treatment by means of constant subcutaneous insulin infusions (CPWI) in patients with diabetes staying in hospital. The infusions were made by means of portable insulin pumps (Microjet Bolus 1, Microjet Bolus 2 and Promedos E 1). The therapy was applied in a group of 15 patients with diabetes admitted to hospital because of symptoms of uncontrolled diabetes, among them 3 patients with diabetes freshly diagnosed. After 2-3 days of infusions 12 patients had glycaemia level approached to the physiological level. Only in one case of diabetes with significant resistance to insulin, the physicians were not able to control the diabetes. After 4-9 days of CPWI, patients who had been given conventional insulin injection had their insulin day demand reduced by 11-33%. In 4 cases the insulin demand had been established by means of Biostator GCIIS, after the introduction of the pumps the demand decreased by 40 +/- 5%, when the open loop system was applied. The above results suggest that the use of constant subcutaneous insulin infusion by means of a dosimeter may be recommended as a method of determining day demand for insulin, significantly shortening hospitalization period in patients with uncontrolled diabetes.

[Morphologic and tumor-marker studies of human planocellular carcinoma of the bronchi in xenografts]

Authors have studied the morphology of 10 human planocellular bronchus carcinoma xenografts parallel with that of the donor tumour. The expression of cytokeratin, epithelial membrane antigen and carcinoembryonic tumour markers was also studied and compared. The histological structure and marker expression of xenografts did not change as compared to the donor tissue. Tumour cells were characterized by cytokeratin rather than epithelial membrane antigen. Carcinoembryonic antigen positivity occurred mainly in well-differentiated tumours. The cellular heterogeneity of human planocellular bronchus carcinomas was found to occur also in xenograft tumours.

Response of the R3327-AT1 Dunning prostate tumor to fast neutrons and cobalt-60

Reasons why neutron therapy may be successful include tumor's rate of proliferation, state of oxygenation at time of onset of radiation and the efficacy of reoxygenation during therapy, inherent radioresistance and repair capacity. In an effort to better understand the action of neutrons on tumor tissues we started studies with the Dunning rat prostate tumor system. This tumor system has sublines available with differing histologies, doubling times, hormone dependency and metastatic potential. The present report pertains to anaplastic carcinoma R3327-AT1 subline. The tumors transplanted into the distal thigh received single doses of 8 through 15 Gy of 14.5 MeV neutrons and 18 through 30 Gy Co-60 after they had reached a volume of about 450 mm3. The tumors exhibited a dose dependent retardation in further growth. An RBE of 3 was estimated by comparing the time required for a tumor to reach a normalized value of five times the initial treatment volume. We plan to extend our studies to include a slower growing well differentiated subline.

Detection of the multidrug resistant phenotype in human tumours by monoclonal antibodies and the streptavidin-biotinylated phycoerythrin complex method

The aim of this study was to find out whether the membrane glycoprotein P-170 can be detected in human tumours with both acquired and intrinsic resistance to chemotherapeutic agents using monoclonal antibodies (265/F4 and C219) and the streptavidin-biotinylated phycoerythrin complex method. Pretreated leukaemia cells and untreated lung and ovarian carcinomas were analysed. Two plasmacytomas and one leukaemia expressed high levels of P-glycoprotein, whereas two leukaemias showed moderate, and three leukaemias no expression of this protein. The intrinsic resistance was analysed with a panel of four human epidermoid lung cancer xenografts grown in nude mice. The expression of P-glycoprotein could be correlated with the degree of resistance. In addition, one out of five ovarian carcinomas revealed a high level of P-glycoprotein.

Detection of P-glycoprotein in human leukemias using monoclonal antibodies

Overexpression of a Mr 170,000 membrane glycoprotein (P-glycoprotein) is consistently associated with multidrug resistance in cell lines. Two monoclonal antibodies (Mab) against P-glycoprotein (265/F4 and C 219) were used to examine tumour samples from patients with leukemias for evidence of P-glycoprotein overexpression. High levels of P-glycoprotein (greater than 5% positive cells) were detected with both antibodies in samples from 3 out of 18 patients suggesting that a multidrug resistant phenotype may also occur in human leukemias.