Arsenic Trioxide Enhances the Radiation Sensitivity of Androgen-Dependent and -Independent Human Prostate Cancer Cells

Prostate cancer is the most common malignancy in men. In the present study, LNCaP (androgen-sensitive human prostate cancer cells) and PC-3 cells (androgen-independent human prostate cancer cells) were used to investigate the anti-cancer effects of ionizing radiation (IR) combined with arsenic trioxide (ATO) and to determine the underlying mechanisms in vitro and in vivo. We found that IR combined with ATO increases the therapeutic efficacy compared to individual treatments in LNCaP and PC-3 human prostate cancer cells. In addition, combined treatment showed enhanced reactive oxygen species (ROS) generation compared to treatment with ATO or IR alone in PC-3 cells. Combined treatment induced autophagy and apoptosis in LNCaP cells, and mainly induced autophagy in PC-3 cells. The cell death that was induced by the combined treatment was primarily the result of inhibition of the Akt/mTOR signaling pathways. Furthermore, we found that the combined treatment of cells pre-treated with 3-MA resulted in a significant change in AO-positive cells and cytotoxicity. In an in vivo study, the combination treatment had anti-tumor growth effects. These novel findings suggest that combined treatment is a potential therapeutic strategy not only for androgen-dependent prostate cancer but also for androgen-independent prostate cancer

histologic variants of glioblastoma in Taiwan

Epidemiology of histologic variants of glioblastoma in Taiwa

Mechanisms of Nanotoxicology and the Important Role of Alternative Testing Strategies

Recently, rapid advances in nanotechnology have provided a lot of opportunities for the mass production of engineered nanomaterials of various types of chemicals, including metals and nonmetals, promoting the development of a new generation of industrial and commercial products and the field of nanomedicine [...

The Recent Progress in Nanotoxicology and Nanosafety from the Point of View of Both Toxicology and Ecotoxicology

This editorial aims to summarize the 14 scientific papers contributed to the Special Issue “Nanotoxicology and nanosafety 2.0 from the point of view of both toxicology and ecotoxicology”

Survival of glioblastoma treated with a moderately escalated radiation dose-Results of a retrospective analysis.

Glioblastoma (GBM) has the highest fatality rate among primary malignant brain tumors and typically tends to recur locally just adjacent to the original tumor site following surgical resection and adjuvant radiotherapy. We conducted a study to evaluate the survival outcomes between a standard dose (≤ 60 Gy) and moderate radiation dose escalation (>60 Gy), and to identify prognostic factors for GBM. We retrospectively reviewed the medical records of primary GBM patients diagnosed between 2005 and 2016 in two referral hospitals in Taiwan. They were identified from the cancer registry database and followed up from the date of diagnosis to October 2018. The progression-free survival (PFS) and overall survival (OS) were compared between the two dose groups, and independent factors for survival were analyzed through Cox proportional hazard model. We also affirmed the results using Cox regression with least absolute shrinkage and selection operator (LASSO) approach. From our cancer registry database, 142 GBM patients were identified, and 84 of them fit the inclusion criteria. Of the 84 patients, 52 (62%) were males. The radiation dose ranged from 50.0 Gy to 66.6 Gy, but their treatment volumes were similar to the others. Fifteen (18%) patients received an escalated dose boost >60.0 Gy. The escalated group had a longer median PFS (15.4 vs. 7.9 months, p = 0.01 for log-rank test), and a longer median OS was also longer in the escalation group (33.8 vs. 12.5 months, p 70 (HR = 1.55), diagnosis after 2010 (HR = 1.42), and a larger radiation volume (≥ 250ml; HR = 0.81) were predictors of PFS. The escalated dose (HR = 0.47) and a larger radiation volume (HR = 0.76) were identified as predictors for better OS. Following detailed statistical analysis, a moderate radiation dose escalation (> 60 Gy) was found as an independent factor affecting OS in GBM patients. In conclusion, a moderate radiation dose escalation (> 60 Gy) was an independent predictor for longer OS in GBM patients. However, prospective studies including more patients with more information, such as molecular markers and completeness of resection, are needed to confirm our findings

Calibration of the EBT3 Gafchromic Film Using HNN Deep Learning

To achieve a dose distribution conformal to the target volume while sparing normal tissues, intensity modulation with steep dose gradient is used for treatment planning. To successfully deliver such treatment, high spatial and dosimetric accuracy are crucial and need to be verified. With high 2D dosimetry resolution and a self-development property, the Ashland Inc. product EBT3 Gafchromic film is a widely used quality assurance tool designed especially for this. However, the film should be recalibrated each quarter due to the “aging effect,” and calibration uncertainties always exist between individual films even in the same lot. Recently, artificial neural networks (ANN) are applied to many fields. If a physicist can collect the calibration data, it could be accumulated to be a substantial ANN data input used for film calibration. We therefore use the Keras functional Application Program Interface to build a hierarchical neural network (HNN), with the inputs of net optical densities, pixel values, and inverse transmittances to reveal the delivered dose and train the neural network with deep learning. For comparison, the film dose calculated using red-channel net optical density with power function fitting was performed and taken as a conventional method. The results show that the percentage error of the film dose using the HNN method is less than 4% for the aging effect verification test and less than 4.5% for the intralot variation test; in contrast, the conventional method could yield errors higher than 10% and 7%, respectively. This HNN method to calibrate the EBT film could be further improved by adding training data or adjusting the HNN structure. The model could help physicists spend less calibration time and reduce film usage

IR dose–response survival curves and cytotoxic effects resulting from ATO and IR in LNCaP and PC-3 cells.

<p>(A) Time-course and dose-dependent effects of IR on the viability of LNCaP and PC-3 cells. Cells were treated with 2, 4, 6 or 8 Gy of IR for 6, 12, 18, 24 and 48 hrs. (B) Time-course and concentration-dependent effects of ATO on the viability of LNCaP and PC-3 cells. Cells were treated with 2, 5, 10 or 15 µM of ATO for 12, 24, 36 and 48 hrs. (C) Cytotoxic effects of cells treated with IR (4 Gy) and ATO (5 µM). (D) The radiation dose–response survival curves of LNCaP and PC-3 cells with or without ATO. Data are presented as the mean ± standard deviation from three independent experiments.</p