Growth inhibition and transformation of a human fetal tracheal epithelial cell line by long-term exposure to diethylnitrosamine

In order to obtain more information on the in vitro transformationof human cells, a human fetal tracheal epithelial cell line(FHET16/5) was exposed for a long time to diethylnitrosamine(DEN). In 20 passages, this cell line (diploid, male) maintainedstrong immunohistochemical reactivity for carcino-embryonnicantigen and wool merokeratin; it was negative for vimentin.The cells contained PAS-positive mucous substances and ultrastructurallywere found to have desmosomelike attachments. Treatment of thecells was with 0.3% dimethyl sulphoxide (DMSO), or DMSO with150, 450, 1000 or 2000 µg/ml of DEN. It was started atthe ninth passage and continued for six passages over 9 weeksfor the control (DMSO) and the three lowest control doses ofDEN, and for three passages over 9 weeks for the 2000 µg/mlDEN group. Cells grown for 13 days after the end of treatmentwere plated in soft agar and injected subcutaneously in nudemice. The frequency of anchorage-independent colonies grownin soft agar was directly related to DEN dose. Colony-formingefficiency, as an expression of toxic effect, was also dosedependent. Autoradiographically detected unscheduled DNA synthesisindicated an association between anchorage-independent transformationand DNA alterations induced by DEN. Cells injected into nudemice did not produce tumours during a 6-month period, but invasivenesswas observed when cells from the 2000 µg/ml DEN groupwere transplanted on the dermis of cultured chick embryo skin.The results indicate that DEN causes anchorage-independent transformationaccompanied by unscheduled DNA synthesis in a fetal human trachealepithelial cell line.     

Inhibitory effects of procaine on the contractile responses of the guinea-pig Taenia caecum to acetylcholine,substance P and potassium chloride

Summary The effect of procaine on the contractile responses to acetylcholine, substance P and KCl was investigated using the isolated guinea-pig taenia caecum. In normal Tyrode solution (37°C), procaine (10–100 mol/l) caused a parallel shift to the right of only the dose-response curve of acetylcholine (pA₂ value, 5.11). The pA₂ value of procaine against acetylcholine was not significantly affected by increasing the Ca concentration in the bathing solution from 0.9 to 7.2 mmol/l. On the other hand, a high concentration of procaine (10 mmol/l) caused a transient contraction of the taenia caecum, but completely suppressed contractions to all concentrations of the agonists. In K-depolarized preparations, procaine (1–10 mmol/l) shifted the dose-response curve for the CaCl₂-induced contraction to the right. Substance P (3 mol/l)-induced contraction of the taenia caecum incubated with Ca-free EGTA (0.1 mmol/l) solution (20°C) was markedly reduced by procaine (10 mmol/l). Using the single sucrose-gap technique, it was found that procaine (10 mmol/l) produced a membrane depolarization and increases in both amplitude and frequency of spontaneous spike discharge. These potential changes were still observed even after the procaine-induced contraction had disappeared. The spike discharges and contraction caused by procaine were abolished in the presence of a Ca-entry blocker, verapamil (10 mol/l). From these observations, it is concluded that at low concentrations procaine acts as a competitive antagonist of muscarinic receptors in the guinea-pig taenia caecum while high concentrations of procaine may depress the contractile responses to acetylcholine, substance P and KCl by inhibiting the Ca-induced Ca release from the intracellular store site or by reducing the transmembrane Ca influx during depolarization.     

Can random bladder biopsies be eliminated after bacillus Calmette–Guérin therapy against carcinoma in situ?

Purpose

Intravesical bacillus Calmette–Guérin (BCG) is the standard of care for bladder carcinoma in situ (CIS). The response to BCG therapy against CIS is generally assessed by random bladder biopsy (RBB). In this study, we examined the necessity of routine RBB after BCG therapy.

Methods

We retrospectively identified 102 patients who were initially diagnosed with CIS with or without papillary tumor and received subsequent 6–8-week BCG therapy. Thereafter, all patients underwent voiding cytology analysis, cystoscopy, and RBB to evaluate the effects of BCG therapy. We evaluated the association between clinical parameters (voiding cytology and cystoscopy findings) and the final pathological results by RBB specimens.

Results

According to the pathological results of RBB, 30 (29%) patients had BCG-unresponsive disease (remaining urothelial carcinoma was confirmed pathologically) and 20 were diagnosed with CIS. Positive/suspicious voiding cytology and positive cystoscopy findings were well observed in patients who had BCG-unresponsive disease compared with their counterparts (p?=?0.116, and p?<?0.001, respectively). The sensitivity (Sen.), specificity (Spe.), positive predictive value (PPV), and negative predictive value (NPV) of voiding cytology were 50%, 68%, 39%, and 77%, respectively. The values for cystoscopy findings were as follows: Sen.: 87%, Spe.: 57%, PPV: 46%, and NPV: 91%. The values for their combination (having either of them) were as follows: Sen.: 100%, Spe.: 44%, PPV: 43%, and NPV: 100%.

Conclusion

RBB after BCG therapy for patients with negative voiding cytology and negative cystoscopy may be omitted because their risk of BCG-unresponsive disease is significantly low (NPV: 100%).

     

A comparative study of portal vein embolization versus radiation lobectomy with Yttrium-90 micropheres in preparation for liver resection for initially unresectable hepatocellular carcinoma

BackgroundPortal vein embolization before liver resection is considered the therapy of choice for patients with inadequate future liver remnants. The concept of radioembolization with Yttrium-90 to achieve the same goal has limited data.MethodsWe retrospectively compared patients who underwent portal vein embolization and Yttrium-90 lobectomy before resection of hepatocellular carcinoma in patients with chronic liver disease.ResultsSeventy-three patients underwent portal vein embolization and 22 patients underwent Yttrium-90. Forty-seven percent of patients before portal vein embolization required additional procedures for tumor control, and 27% of patients after Yttrium-90 required additional procedure to mainly induce further hypertrophy. Both therapies achieved the goal of future liver remnants >40%, but the degree of hypertrophy was significantly higher in Yttrium-90 patients (63% for Yttrium-90, 36% for portal vein embolization, P < .01). Tumor response was significantly better with Yttrium-90, achieving complete response in 50% of patients. Resectability rate was higher after portal vein embolization (85% for portal vein embolization, 64% for Yttrium-90, P = .03). Tumor progression was the most common reason precluding surgery. Complete tumor control was the reason not to pursue surgery in 18% of patients after Yttrium-90.ConclusionBoth preoperative portal vein embolization and Yttrium-90, increases liver resectability rates by inducing hypertrophy of future liver remnants in patients with hepatocellular carcinoma and chronic liver disease. Yttrium-90 lobectomy achieved better tumor control and provided more time to assess therapy response, optimizing the indication for surgery.     

Assessment of high-energy phosphorus compounds in the rat kidney by in situ31P nuclear magnetic resonance spectroscopy: effect of ischemia and furosemide

Summary ³¹P nuclear magnetic resonance (NMR) spectroscopy of the in situ rat kidney was performed by a surface coil method, and the effects of ischemia and furosemide infusion were assessed.³¹P NMR spectra of the kidney subjected to 30 min of ischemia returned completely to the pre-ischemic level after 60 min of reperfusion. But the³¹P NMR spectra after 60 min of ischemia did not recover, even after 120 min of reperfusion. Levels of -ATP and inorganic phosphate (Pi) decreased and the chemical shift of Pi increased after intravenous infusion of furosemide. This increase in chemical shift might signal an alkalotic change in intracellular pH. Furosemide infusion prior to ischemia is thought to protect the kidney from injury induced by 60 min of warm ischemia. The chemical shift of Pi returned to the pre-ischemic level earlier than -ATP and Pi. In conclusion, according to the findings of³¹P NMR spectroscopy, furosemide infusion prior to ischemia may be effective in protecting the kidney against ischemic injury. But the change in Pi peak and the causes of the dissociation of Pi and -ATP should be examined further.     

Influence of ETR-p1/f1 antisense peptide on endothelin-induced constriction in rat renal arcuate arteries

1. This study set out to examine the endothelin receptor subtypes mediating vasoconstriction in the rat renal arcuate artery. This was done in isolated vessels 120–200 μm in diameter, incubated with a selective agonist and the novel ‘antisense'' peptide to part of the human endothelin_A receptor.
2. Groups of vessels (n=6) were incubated with increasing concentrations of endothelin-1 (ET-1), from 1 to 100 nM, which caused a 65% maximal contraction at the highest dose with an pEC₅₀ of 8.16±0.11 M. By contrast, in six other vessels sarafotoxin 6c over the same dose range gave a minimal contraction (around 5% of maximum).
3. Preincubation of six vessels with the antisense peptide ETR p₁/f1 at 1 μM had no effect on the ET-1 induced vasoconstriction, in terms of displacement of the concentration-response curve or the maximal tension achieved by the agonist. In the six vessels exposed to 4 μM ETR p₁/f1, there was a significant shift of the concentration-response curve and a lower pEC₅₀ at 7.78±0.09 M (P<0.05). At the highest concentrations of ETR p₁/f1, there was a marked suppression of all responses to ET-1, which at the maximal concentrations tested, 0.1 μM, only reached some 10% of the maximal achievable contraction.
4. Increasing ET-1 concentrations up to 2 μM in vessels incubated with 40 μM ETR-p₁/f1 showed that the blockade could be overcome and that the relationship was shifted to the right (P<0.001) by approximately one log unit with a pEC₅₀ of 7.13±0.11 M. A Schild plot of the data indicated the antagonist to be acting competitively at a single population of receptors.
5. At the highest concentrations tested, 40 μM, ETR-p₁/f1 had no effect on noradrenaline-induced contractions, indicating a lack of non-specific actions.
6. Together, these data suggest that at the rat renal arcuate artery the endothelin_A receptor is the predominant functional receptor mediating contraction. Furthermore, this study has shown the potential usefulness of this novel type of ‘antisense'' peptide in blocking receptor activation.

     

Influence of 1 alpha,25-dihydroxyvitamin D-3 on growth regulation through epidermal growth factor receptor in human breast cancer cell lines

We investigated the relationship between epidermal growth factor (EGF) dependent cell growth and antiproliferative effects of 1 alpha,25-dihydroxyvitamin D-3 (1,25(OH)(2)D-3) in hormone responsive breast cancer cell lines in vitro. MCF-7 breast cancer cells and GMC-M, which is a serum-independent, hormone receptor-positive subtype derived from MCF-7, were used in this study. EGF stimulated the growth Of both cell lines, and 1,25(OH)(2)D-3 inhibited the EGF-stimulated cell growth in a dose dependent fashion. But treatment with 1,25(OH)(2)D-3 did not change the EGF receptor (EGFR) level significantly in either cell line. GMC-M had a higher level of EGFR and was more sensitive to EGF than MCF-7. These results suggest that other mechanisms of action, which are different from EGFR modulation, concern with the growth inhibitory effect of 1,25(OH)(2)D-3, and that 1,25(OH)(2)D-3 will be a new effective treatment for breast cancer irrespective of EGFR.     

Computer-aided diagnosis in full digital mammography

RATIONALE AND OBJECTIVES: The authors clarify the detection rates for breast cancerous tumors and clustered microcalcifications with computer-aided diagnosis (CAD) based on Fuji Computed Radiography. The authors also determine whether mammographic reading with CAD contributes to the discovery of breast cancer. METHODS: Data acquired by Fuji Computed Radiography 9000, which consisted of 4148 digital mammograms including 267 cases of breast cancer, was transferred directly to an analysis workstation where an original software program determined extraction rates for breast tumors and clustered microcalcifications. Furthermore, using another 344 mammograms from 86 women, observer performance studies were conducted on five doctors for receiver operating characteristic (ROC) analysis. RESULTS: Sensitivity to breast cancerous tumors and clustered microcalcifications were 89.9% and 92.8%, respectively false-positive rates were 1.35 and 0.40 per image, respectively. The observer performance studies indicate that an average Az value for the five doctors was greater with the CAD system than with a film-only reading without CAD, and that a reading with CAD was significantly superior at P < 0.022. CONCLUSIONS: It has been shown that CAD based on Fuji Computed Radiography offers good detection rates for both breast cancerous tumors and clustered microcalcifications, and that the reading of mammograms with this CAD system would provide potential improvement in diagnostic accuracy for breast cancer.     

Effects of long-term treatment with trandolapril on augmented vasoconstriction in rats with chronic heart failure

Background:

Despite the clinical relevance of angiotensin I-converting enzyme (ACE)inhibitors, their effects on impaired vascular function in patients and animals with chronic heart failure (CHF) have not been fully understood. This study was undertaken to determine whether long-term treatment with an ACE inhibitor improved the altered contractile properties of vessels from rats with CHF.

Methods and Results:

Twelve weeks after coronary artery ligation, the rats were sacrificed and the isometric tension development of thoracic aorta, pulmonary artery, and mesenteric artery with and without endothelium was examined. Contractile responses to norepinephrine and prostaglandin F₂α were augmented in endothelium-intact, but not in endothelium-denuded, thoracic aorta and pulmonary artery segments of the rat with CHF. The contractile response to angiotensin II was augmented in endothelium-denuded mesenteric artery segments of the rat with CHF, which was attenuated by indomethacin or diclofenac sodium but not by bunazosin. Trandolapril (3 mg/kg/d) was administered orally from the 2nd to 12th week after the operation. Treatment with trandolapril reversed the augmented contractile response of the rat with CHF to norepinephrine, prostaglandin F₂α, and angiotensin II almost to the levels in the sham-operated rat.

Conclusions:

The results demonstrate that an ACE inhibitor is capable of reversing altered vascular function in the rat with CHF, suggesting that vascular beds are possible sites of action for ACE inhibitors in the therapy for CHF.     

Hyperthermo-chemotherapy combined with cytoreductive surgery for the treatment of gastric cancer with peritoneal dissemination

Continuous hyperthermic peritoneal perfusion (CHPP) with anticancer agents (mitomycin C and cisplatin) in warm saline was performed in patients with peritoneal dissemination of gastric cancer following resection of the primary lesion. The effect of CHPP was examined by a second-look operation. This study includes 41 cases of gastric cancer with peritoneal dissemination but without liver metastasis treated during the past 6 years. The overall median survival was 14.6 months to 64.2 months from CHPP to death and the 3-year survival rate was 28.5%. Second look surgery revealed a remarkable diminution in the degree of peritoneal dissemination in 7 (50%) of 14 patients with disappearance of ascites after only one course of CHPP in 7 (77.8%) of 9 patients. Long-term 3 year-survival was noted in 4 (9.8%) patients on CHPP. Side effects were renal insufficiency in 2 (5%) patients, leukopenia in 2 (5%) patients, and perforation of the small intestine in 1 (2%) patient. These results suggest the effectiveness of CHPP in the treatment of gastric cancer with peritoneal dissemination.

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Resumen La perfusión hipertérmica continua (PHTC) con agentes anticancerosos (mitocina G y cisplatino) y solutión salina fue realizada en pacientes con cáncer gástrico con diseminación peritoneal después de resección de la lesión primaria, y el efecto de PHTC fue determinado mediante reexploración (operación de second look, OSL). La población de pacientes está constituída por 41 casos de cáncer gástrico con diseminación peritoneal pero sin metástasis hepáticas, tratdos en el curso de los últimos 6 años. La sobrevida media global fue de 437 dias (rango 28 a 1925 días) desde la PHTC hasta la muerte y la tasa de sobrevida a 3 años fue 28.5%. La OSL reveló una notoria disminución de la diseminación peritoneal en 7 (50%) de 14 casos y desaparición de la ascites después de sólo un ciclo de PHTC en 7 de 9 casos con ascitis. Sobrevida de 3 años ocurrió en 4 casos. Los efectos colaterales fueron insuficiencia renal en 2 casos (5%), leucopenia en 2 casos (5%) y perforación del intestino delgado en 1 caso (2%). Los anteriores resultados sugieren que la PHTC es eficaz en el tratamiento del cáncer gástrico con diseminación peritoneal.

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Résumé La perfusion péritonéale continue hyperthermique (PPCH) avec des agents anticancéreux comme le mitomycine C et la cis-platine avec sérum physiologique chauffé a été instaurée lorsqu'une carcinose d'origine gastrique a été trouvée. Les effets de la PCH ont été évalués chez 16 patients lors d'un second-look (SL). Cette étude concerne 41 patients avec carcinose péritonéale sans métastase hépatique observés au cours des 6 dernières années. La survie globale médiane était de 437 jours (extrêmes 28 à 1925 jours): le taux de survie a 3 ans était de 28.5%. Les lésions avaient diminué de façon notable chez 7 (50%) de 14 patients. L'ascite a disparu dans 7 des 9 cas. Une survie à long terme (3 ans) a été notée dans 4 cas. Les effets secondaires ont été une insuffisance rénale dans 2 cas (5%), une leucopénie dans 2 cas (5%) et une perforation de l'intestin grêle dans un cas (2%). Les résultats suggèrent que la PPCH est efficace dans le traitement du cancer gastrique avec dissémination péritonéale.