In vitro early changes in intercellular junctions by treatment with a chemical carcinogen

To examine early intercellular junction changes caused by treatmentwith 9, 10-dimethyl-l, 2-benzanthracene (DMBA), rat lingualepithelium was cultivated in isolation and observed by electrophysiological,freeze-fracture and whole-mount electron microscopy. Electrophysiologicalmeasurements showed a transient decrease in membrane potentialof -10.2 mV 6 h after the treatment. It returned to almost thesame level as that of the control group 1 day later. Six hoursafter treatment, input resistance decreased rapidly to 5.3 Mbut increased to 18.0 M 12 h after treatment. Transient reductionof input resistance and membrane potential occurred prior tothe decrease in the coupling ratio 6 h after treatment withDMBA. In freeze-fracture replicas, the number of gap junctionsdecreased by 45% of the control value 6 h after treatment withDMBA. At 12 h and thereafter, the number and area of gap junctionssubsequently decreased by 60–80% of the control value.Alterations in the number and area of desmosomes were similarto those of the gap junctions. The formation of epithelial cytoskeletons,partially devoid of the 2–4 and 5–8 nm filamentswas also observed. A decrease in the density of filament networksbeneath the plasma membranes was especially apparent. Treatmentwith a carcinogen brought about morphological cellular changesas early as 6 h after treatment, and such early changes mighttrigger metabolic cellular abnormalities. Affected cells appearto move away from normal cells in a process of repeated destructionand revision of intercellular junctions, and cytoskeletons.     

Therapeutic effects of the combined androgen blockade therapy versus luteinizing hormone-releasing hormone analog monotherapy in patients with hormone naïve metastatic prostate cancer: a multi-institutional comparative analysis

BackgroundThe clinical benefit of the combined androgen blockade (CAB) therapy over luteinizing hormone-releasing hormone analog (LH-RHa) monotherapy for hormone naïve metastatic prostate cancer (mHNPC) is unclear. Therefore, we retrospectively compare the effectiveness of CAB with the LH-RHa monotherapy on the prognosis of Japanese patients with mHNPC.MethodsWe retrospectively evaluated the prognosis of 517 patients diagnosed with mHNPC between August 2001 and May 2017. The patients’ data were obtained from the Michinoku Urological Cancer Research Group database and Hirosaki University-related hospitals. Patients were divided into the CAB and LH-RHa monotherapy groups based on primary androgen deprivation therapy (ADT). Overall survival (OS), cancer-specific survival (CSS), and castrate-resistant prostate cancer-free survival (CRPC-FS) were compared between the two groups using the Kaplan-Meier curve analysis. Inverse probability of treatment weighting (IPTW)-adjusted Cox hazard proportional analyses was performed to investigate the effect of primary ADT on oncological outcomes.ResultsThe median age was 73 years old. The numbers of patients in the CAB and LH-RHa monotherapy groups were 447 and 70, respectively. The Kaplan-Meier curve analysis showed no significant differences in either 5-year OS (56.7% vs. 52.5%, P=0.277), CSS (61.1% vs. 56.4%, P=0.400), and CRPC-FS (33.1% vs. 31.1%, P=0.529) between the groups. IPTW-adjusted multivariate Cox hazard proportional analyses showed no significant differences in OS, CSS, and CRPC-FS between the two groups.ConclusionsNo significant differences in oncological outcomes were observed between the CAB and LH-RHa monotherapy groups in patients with mHNPC.     

Osteosarcoma occurring in osteogenesis imperfecta

We describe a case history of a 24-year-old male with osteogenesis imperfecta (OI) who developed osteosarcoma of the left thigh. High-dose ifosfamide therapy caused marked tumor regression of multiple lung metastases. Immunohistochemically, the tumor cells were diffusely positive for the p53 protein. Mutation of the p53 gene was not detected by direct genomic sequencing of exons 4–8. The radiographic characteristics, including irregularly distributed osteolytic lesions and cortical discontinuity, should not be confused with hyperplastic callus formation, a benign process. A biopsy is critical to establish the differential diagnosis between osteosarcoma and common hyperplastic callus formation in OI; however, it must be applied with great care.     

Growth suppression of non-small cell lung carcinoma cells by the introduction of the p16(INK4A) gene

The p16(INK4A) gene is frequently inactivated in nonsmall cell lung carcinoma (NSCLC) by either mutations, deletions or DNA methylations. To assess the biological significance of p16(INK4A) inactivation in the development of NSCLC, full-length p16(INK4A) cDNA was introduced into NSCLC cell lines, A549 and H322, in which p16(INK4A) was homozygously deleted. NSCLC cells transfected with the p16(INK4A) expression vector formed colonies in 20-68% of those with a control vector, and exogenous p16(INK4A) protein was expressed in 4 of 68 A549-derived clones and none of 29 H322-derived clones, respectively. A549-derived clones which stably expressed the exogenous p16(INK4A) gene showed significant decrease in growth rate in vitro and tumorigenicity in vivo in proportion to the level of p16(INK4A) expression. Furthermore, the cell cycle of these cells significantly delayed with accumulation of cells in G1 phase. Micro-injection of p16(INK4A) expression vector also revealed that p16(INK4A) blocked S phase entry in both A549 and H322 cells. These results suggest that the restoration of the p16(INK4A) function suppresses the growth of NSCLC cells by induction of G1 arrest in the cells. Therefore, inactivation of p16(INK4A) may play an important role in the enhancement of unregulated NSCLC growth in vivo.     

Transthoracoscopic needle biopsy for indeterminate lung nodules

Background: The usefulness of transthoracoscopic needle biopsy for preoperatively indeterminate intrapulmonary nodules was evaluated. Methods: Thoracoscopy was performed on 38 patients with pulmonary solitary nodules suspected to be primary lung carcinomas. When the nodule was localized by simple observation or tactile sensor, a biopsy specimen of the tumor was obtained by a biopsy needle introduced through a trocar. Results: The nodules were 7 to 55 mm in diameter. All were located in the peripheral region of the lung. Biopsy specimens were obtained even from 17 nodules with no associated pleural changes. By cytology, all the malignant tumors were precisely diagnosed, 29 as primary lung cancers and 3 as metastatic lung neoplasms. Five of the remaining six benign nodules were not precisely diagnosed. However, they were cytologically classified as class I. Conclusions: Transthoracoscopic needle biopsy is feasible for diagnosing small intrapulmonary nodules, particularly those of malignant neoplasms. As compared with thoracoscopic excisional biopsy, transthoracoscopic needle biopsy saves time and may reduce the possibility of tumor dissemination during the procedure. Received: 14 March 1997/Accepted: 31 May 1997     

Suppression of conditioned fear by administration of CCKB receptor antagonist PD135158

In order to examine the involvement of CCK in the formation of anxiety, we have investigated whether CCKB receptor antagonist PD135158 suppressed conditioned fear stress. Rats were individually subjected to 30 min of inescapable electric footshock in a chamber with a grid floor. First, the rats were individually subjected to 30 min of footshock. Twenty-four h after the footshock, the rats were again placed in the chamber and observed for 5 min without shocks. PD135158 was administered 30 min before placing the rats in the chamber again. Secondly, PD135158 was administered 30 min before footshock. Thirdly, PD135158 was administered 5 min after footshock. Administration of PD135158 30 min before conditioned fear stress significantly reduced freezing behavior. Administration of PD135158 30 min before footshock also significantly reduced freezing behavior. But, administration of PD135158 5 min after footshock did not significantly reduce freezing behavior. PD135158 blocked not only the acquisition but also the expression of conditioned fear. These results suggest that the CCKB receptor might play an important role in conditioned fear stress and that it might be related to anxiety.     

Neuroradiologic findings in glutaric aciduria type II

The authors report a 3-year-old male with glutaric aciduria type II, whose magnetic resonance imaging studies revealed agenesis of the cerebellar vermis and hypoplastic temporal lobes. Proton magnetic resonance spectroscopy in the parietal white matter revealed a markedly increased choline/creatine ratio, suggesting a demyelinating process. Gas chromatographic analysis of urinary organic acids should be studied in any patient with agenesis of the cerebellar vermis and cystic renal disease to exclude glutaric aciduria type II.     

Peripheral choriovitreal neovascularization in proliferative diabetic retinopathy: histopathologic and ultrastructural study

We describe the histopathologic and ultrastructural evidence of choriovitreal neovascularization in the peripheral fundus of a non-vitrectomized eye with proliferative diabetic retinopathy (PDR). One eye with PDR was surgically enucleated because of neovascular glaucoma and studied with light and electron microscopy. The eye had neovascular membranes at the ora serrata of the peripheral fundus. The newly formed vessels originated from the choroid, passed through Bruch's membrane and the retina, and extended into the vitreous. These vessels had either developing or mature characteristics. The endothelial cells of the developing vessels contained a bulky cytoplasm with many intracytoplasmic filaments, ribosomes and rough endoplasmic reticulum. Budding endothelial cells were frequently found in the developing vessels. The endothelial cells of the mature vessels had attenuated cytoplasm and fenestrations with diaphragms. These observations suggest that choriovitreal neovascularization in the peripheral fundus is one of the features of PDR.     

Excimer laser-induced hydroxyl radical formation and keratocyte death in vitro

PURPOSE: To characterize the type of reactive oxygen species (ROS) produced by excimer photoablation of aqueous solutions and to show the effects of ROS and antioxidants on corneal stromal cells in vitro. METHODS: Electron spin-resonance spectroscopy was performed using the spin-trapping agent 5,5-dimethyl-1-pyrroline N-oxide (DMPO) for the detection of the superoxide anion and the hydroxyl radical in an acellular DMPO solution irradiated with the excimer laser. Hydroxyl radicals were produced by the Fenton reaction in vitro by the mixture of hydrogen peroxide and ferrous iron (Fe2+), and the effects on cultured corneal fibroblasts were observed by fluorescent microscopy using the cell death marker, propidium iodide (PI) and TdT-mediated dUTP nick-end labeling (TUNEL). RESULTS: Excimer photoablation of a 1% DMPO solution produced a species-specific spin-trapping adduct for the hydroxyl radical ('OH), but not for the superoxide anion or other unidentified free radical. The signals were inhibited dose dependently by the hydroxyl radical scavenger dimethylsulfoxide (DMSO) and an L-ascorbic acid analogue, EPCK-1. The production of *OH in the supernatant of cultured rabbit corneal fibroblasts by the Fenton reaction caused an increase in PI (+) and TUNEL (+) cells by 90 minutes, which was significantly inhibited by the addition of DMSO. CONCLUSIONS: Hydroxyl radicals may be partly responsible for stromal fibroblast cell apoptosis after excimer photoablation.