Lonidamine induces apoptosis in drug-resistant cells independently of the p53 gene

Lonidamine, a dichlorinated derivative of indazole-3-carboxylic acid, was shown to play a significant role in reversing or overcoming multidrug resistance. Here, we show that exposure to 50 microg/ml of lonidamine induces apoptosis in adriamycin and nitrosourea-resistant cells (MCF-7 ADR(r) human breast cancer cell line, and LB9 glioblastoma multiform cell line), as demonstrated by sub-G1 peaks in DNA content histograms, condensation of nuclear chromatin, and internucleosomal DNA fragmentation. Moreover, we find that apoptosis is preceded by accumulation of the cells in the G0/G1 phase of the cell cycle. Interestingly, lonidamine fails to activate the apoptotic program in the corresponding sensitive parental cell lines (ADR-sensitive MCF-7 WT, and nitrosourea-sensitive LI cells) even after long exposure times. The evaluation of bcl-2 protein expression suggests that this different effect of lonidamine treatment in drug-resistant and -sensitive cell lines might not simply be due to dissimilar expression levels of bcl-2 protein. To determine whether the lonidamine-induced apoptosis is mediated by p53 protein, we used cells lacking endogenous p53 and overexpressing either wild-type p53 or dominant-negative p53 mutant. We find that apoptosis by lonidamine is independent of the p53 gene.

[Induratio penis plastica: the diagnostic possibilities of gradient-echo sequences (magnetic resonance angiography)]

The authors investigated the diagnostic capabilities of gradient echo sequences (magnetic resonance angiography) in the study of induratio penis plastica. Twenty patients (mean age: 39 years) were examined. MRA was performed with a superconductive magnet (1.5 T) and a Helmoutz coil; the dynamic test with PGE (20-40 mg) was also carried out. The images acquired on the axial and sagittal planes were processed according to the MIP. The FLASH 2D sequence was used with the following parameters: FA 18 degrees, TR 40 ms, TE ms, MA 256 x 256, slice thickness 5 mm. A multiple choice card was filled in by a reader with the following diagnostic information: identification and localization of the plaques and involvement by the plaques of the albuginea, corpora cavernosa, septum and dorsal vein; surgery was the gold standard. MRA showed 10/11 plaques ranging 8-30 mm in diameter and missed a 5-mm plaque. Moreover, MRA depicted the infiltration of the albuginea in 10/10 cases, of the septum in 3/3 cases, of the dorsal vein in 4/4 cases and of the corpora cavernosa in 9/9 cases. Our preliminary experience shows that in the study of induratio penis plastica, the gradient echo sequence (MRA) permits better depiction of the plaques and of the infiltration of the corpora cavernosa, septum and albuginea.

[The peripheral circulation: ECG-gated magnetic resonance angiography]

This work was aimed at comparing magnetic resonance angiography (MRA) with and without ECG gating in the study of peripheral vessels. Ten volunteers, mean age 27.8 years, were examined with MRA of the femoral, popliteal and tibial segments. MRA was performed with a 1.5-T superconductive magnet, a transmit head coil and the TOF 2D technique. In all cases MRA was performed without cardiac gating and with different times of trigger delay (0, 20, 40, 70 and 200 ms). When comparing the different acquisitions, the number of vessels and the signal-to-noise (S/N) ratio were calculated. In the femoral segment, MRA without cardiac gating showed a mean of 7.7 vessels with 2.79 S/N ratio; MRA with 0 ms of trigger delay showed a mean of 13.1 vessels with 1.51 S/N ratio; MRA with 20 ms trigger delay showed a mean of 13.1 vessels with 1.52 S/N ratio; MRA with 40 ms trigger delay showed a mean of 13.2 vessels with 1.52 S/N ratio; MRA with 70 ms trigger delay showed a mean of 13.5 vessels with 1.50 S/N ratio; finally, MRA with 200 ms trigger delay showed a mean of 13.4 vessels with 1.50 S/N ratio. In the popliteal segment, the corresponding values were 6.4 vessels and 2.51 S/N ratio, 11.4 vessels with 1.54 S/N ratio, 11.3 vessels and 1.54 S/N ratio, 11.6 vessels and 1.52 S/N ratio, 11.8 vessels and 1.52 S/N ratio and, finally, 11.9 vessels and 1.52 S/N ratio. In the tibial segment, the corresponding values were 8.5 vessels and 1.84 S/N ratio, 14.4 vessels and 1.14 S/N ratio, 14.5 vessels and 1.17 S/N ratio, 14.5 vessels and 1.14 S/N ratio, 14.3 vessels and 1.17 S/N ratio and, finally, 14.5 vessels and 1.19 S/N ratio. To conclude, MRA with cardiac gating better visualized peripheral vessels whatever the trigger delay.

[Diagnostic pitfalls in magnetic resonance angiography]

The authors report on their clinical experience with Magnetic Resonance angiography (MRA) pitfalls. January, 1989, to February, 1995, six hundred MRA examinations were performed in different vascular districts, with a 1.5-T superconductive magnet, the time-of-flight (TOF) technique and 2D and 3D acquisitions. Intracranial arteries, epiaortic vessels and renal arteries were studied with FISP 3D sequences; intracranial veins, thoracic vessels, vena cava and pelvic vessels were studied with FISP 2D sequences. Pitfalls were observed in 56 of 600 MRA exams (9.3%). Of 56 pitfalls, 26 (46.4%) were in epiaortic vessels, 15 (26.7%) in intracranial vessels, 6 (10.7%) in renal arteries, 6 (10.7%) in thoracic vessels, 1 (1.7%) in the inferior vena cava and 2 (3.5%) in iliac vessels. Stenoses were overestimated in 21 patients and underestimated in three; 16 patients were misdiagnosed and 16 were false positives. As for cerebral vascular lesions, 5 aneurysms and 7 transverse sinus thromboses were false positives, while 3 lesions were misdiagnosed as venous angiomas. As for 26 MRA exams of thoracic vessels, stenoses were overestimated in 16 patients and underestimated in 10 patients with subclavian steal syndrome, where the left vertebral artery was misinterpreted as occluded. In 6 MRA exams of thoracic vessels, 1 patient was misdiagnosed as having an aneurysm and 5 patients were misdiagnosed as having lung cancer infiltrating aorta and superior vena cava. As for renal vessels, 2 normal renal arteries were misdiagnosed as false positives and 4 stenoses were overestimated. In the inferior vena cava, a partial agenesis was misinterpreted as thrombosis. In 2 MRA exams of iliac vessels, a stenosis and a thrombosis were misinterpreted as false positives. Our experience suggests that MRA pitfalls are caused by the incorrect use of the various techniques. The pitfalls we observed can be classified as caused by three types of artifacts: saturation, turbulence and paramagnetic substance artifacts.

DNA ploidy, proliferative index, and epidermal growth factor receptor: expression and prognosis in patients with gastric cancers

BACKGROUND

The 5-year survival rate of patients with stomach cancer is usually around 20%. The clinico-pathological features that are presently used to assess patient prognosis are not sufficient to define gastric tumor behavior. Therefore, an accurate analysis of different biological characteristics of gastric cancer cells could allow the course of disease to be predicted and may help to improve treatment strategies.

EXPERIMENTAL DESIGN

The prognostic values of DNA ploidy, proliferative activity and epidermal growth factor receptor (EGF-R) expression were studied in gastric tumors from a series of 63 patients. DNA ploidy and proliferative activity, evaluated in terms of DNA index (DI) and proliferative index (PI), respectively, were determined by flow cytometry on paraffin-embedded tumor tissues. EGF-R expression was detected by immunohistochemistry on paraffin-embedded tumor sections of the same specimens. The clinico-pathological and the biological parameters were then correlated, and the patients overall survival was calculated using a chi-square test and the Kaplan-Meier method.

RESULTS

DNA ploidy abnormal cell clones were found in 44% of cases (median DI = 1.4, range 1.04-2.5). Aneuploid tumors showed high PI more frequently than diploids (71% versus 36%, p = 0.01). The analysis of the expression of EGF-R revealed that 88% of aneuploid tumors were positive for receptor expression. On the contrary, diploid tumors showed the presence of EGF-R only in 56% of cases (p = 0.01). DI, PI, and EGF-R expression were not related to histological grade. Conversely, the three biological parameters were significantly correlated to clinical stage and tumor invasion. The Kaplan-Meier survival curves showed a 73% 5-year survival rate in patients with diploid tumors whereas only 33% of patients with aneuploid lesions had a good prognosis (p = 0.001).

CONCLUSIONS

We demonstrate that DNA ploidy, PI, and EGF-R expression are closely related to some pathological and clinical characteristics in gastric cancer. The close relationship between aneuploidy, EGF-R positive expression, node involvement, and tumor invasion suggests that these parameters may be indicators of high malignancy. Finally, the results also show that aneuploidy and EGF-R-positive expression are indicative of a worse prognosis in gastric cancer patients. The study of these parameters might allow a more accurate stratification of patients, so that a targeted therapeutic protocol may be defined.

Gastric cancer cell DNA content correlates with early and late results after gastrectomy

The DNA content of 59 adenocarcinomas of the stomach in patients who had undergone subtotal or total gastrectomy more than 5 years before was measured. The DNA measurements were done by flow cytometry performed on Propidium Iodide--stained cells disaggregated from paraffin-embedded tissues. Fifty-nine evaluable good quality histograms of DNA ploidy patterns were obtained. The Proliferative Index (PI) was determined in 35 cases. The remaining 24 cases didn't show a reliable reading histograms. Of the 59 tumors, 33 (56%) were diploid and 26 (44%) were aneuploid; 19 showed a high PI (> or = 3.8%) and 16 a lower one. A statistically significant difference was found between the two groups (diploid/aneuploid and low/high PI) compared to the prognostic values known as T, N and Stage. 65% of the T3-T4 cancers, 54% of the N1-N2 lesions and 58% of the stage III and IV were found to be aneuploid. 73.7% of the 19 tumors presenting high PI, showed an aneuploid pattern. A high PI was found in 71.4% of the T3-T4 tumors. 77.4% of patients of the diploid group (any stage) survived at 5 years against 36% of those presenting aneuploid patterns. Patients with PI > or = 3.8% showed a 42.1% 5-year survival rate. A 94.4% 5-year survival rate of diploid and early stage cancers was documented against a 33.5% of aneuploid and advanced stage cancers.

Circulating diphtheria antitoxin levels in children aged 11-14 years in relation to the vaccinal history

Diphtheria antitoxin level in serum samples obtained from 204 healthy children aged 11-14 years was determined by means of an indirect haemagglutination technique and related to the vaccinal history of the subjects. Irrespective of the time since the last toxoid inoculation, the mean antitoxin titre per ml of serum in the individuals who had received incomplete/irregular anti-diphtheria vaccination in childhood was significantly higher when the number of toxoid doses was higher (from two to more than four doses); the same was not observed for individuals given primary vaccination (three toxoid doses) according to the schedule for childhood vaccination in Italy (regular vaccinees) and one or more booster doses. Between 8 and 13 years after the last of three toxoid doses, a significantly negative association between mean antitoxin titre and time was observed only in irregularly vaccinated children (r = -0.82; p less than 0.05); nevertheless, up to thirteen years after the last vaccine dose, more than 95% of the children exhibited protective levels of antitoxin (greater than 0.125 turkey red blood cells passive haemagglutination units per ml). No significant decrease in mean antitoxin titre was observed between 4 and 10 years after the last of four either regularly or irregularly administered toxoid doses.

[Total intravenous anesthesia with propofol vs. propofol/N2O anesthesia]

The authors have compared two groups of 31 patients each, undergone an anaesthesia with propofol-O2/N2O (group I) and propofol-O2/air (group II). The average anaesthetic dosage and the neuromuscular recovery time have been valued, keeping constant the dose of analgesic. The average consumption of propofol (except the inductive dose of 2 mg/kg) was 7.41 +/- 1.71 mg/kg/h in group I, and 7.47 +/- 1.76 in group II (p = 0.88; not significant) and the neuromuscular recovery time 56.12 +/- 34.55 m' and 49.48 +/- 40.50 m' respectively (p = 0.53; not significant). The cardiocirculatory parameters have been compared at the time of induction, surgical incision and for all the operation time, reporting every undesired effect. The awakening has been monitored until 15 m' from the interruption of propofol infusion. The data obtained don't permit to observe significant differences with regard to analgesia, neuromuscular block and awakening time. Therefore the authors put the question of the real necessity to use nitrous oxide, when it has utilized an efficient intravenous anaesthetic as the propofol has proved to be.

[A case of Ramsay Hunt syndrome]

We describe a clinical case of RH syndrome (Auricular Herpes zoster, facial paralysis, hearing loss).