11C-harmine as a potential PET tracer for ductal pancreas cancer: in vitro studies

Molecular Imaging of Monoamine Oxidase A Expression in Highly Aggressive Prostate Cancer: Synthesis and Preclinical Evaluation of Positron Emission Tomography Tracers

The role of monoamine oxidase A (MAO-A) in the aggressiveness of prostate cancer (PCa) has been established in recent years. The molecular imaging of MAO-A expression could offer a noninvasive tool for the visualization and quantification of highly aggressive PCa. This study reports the synthesis and preclinical evaluation of 11C- and 18F-labeled MAO-A inhibitors as positron emission tomography (PET) tracers for proof-of-concept studies in animal models of PCa. Good manufacturing practice production and quality control of these radiotracers using an automated platform was achieved. PET imaging was performed in an LNCaP tumor model with high MAO-A expression. The tumor-to-muscle (T/M) uptake ratio of [11C]harmine (4.5 ± 0.5) was significantly higher than that for 2-[18F]fluoroethyl-harmol (2.3 ± 0.7) and [11C]clorgyline (2.0 ± 0.1). A comparable ex vivo biodistribution pattern in all radiotracers was observed. Furthermore, the tumor uptake of [11C]harmine showed a dramatic reduction (T/M = 1) in a PC3 tumor model with limited MAO-A expression, and radioactivity uptake in LNCaP tumors was blocked in the presence of nonradioactive harmine. Our findings suggest that [11C]harmine may serve as an attractive PET probe for the visualization of MAO-A expression in highly aggressive PCa. These radiotracers have the potential for clinical translation and may aid in the development of personalized therapeutic strategies for PCa patients.

New developments in the early diagnosis of pancreatic cancer

Pancreatic cancer is an aggressive carcinoma of the digestive system and radical resection, which is available to very few patients, is the only possibility for cure. Since therapeutic choices are limited at the advanced stage, screening and early diagnostic tools are indispensable for a better prognosis. Areas covered: This review illustrates serologic and imaging examinations, and carbohydrate antigens, microRNAs, methylation biomarkers, molecules in exosomes, ultrasound, computed tomography, magnetic resonance imaging, positron emission tomography and endoscopic retrograde cholangiopancreatography, among other topics. No matter which approach is used, the accuracy of early diagnosis is extremely low. Combining different methods greatly improves the accuracy of early diagnosis. This review was conducted utilizing PubMed with key search words pancreatic cancer, early diagnosis, biomarkers and imaging. Expert commentary: Appropriate combination of biomarkers and imaging technologies will become standard practice in the future. Because the incidence of and mortality from pancreatic cancer is rising, further study of new approaches for the early detection of pancreatic tumors is essential.

Harmine hydrochloride inhibits Akt phosphorylation and depletes the pool of cancer stem-like cells of glioblastoma

Harmine hydrochloride (Har-hc), a derivative from Harmine which is a natural extractive from plants, has been considered for treatment of kinds of cancers and cerebral diseases. In this study, we found that Har-hc clearly decreased cell viability, induced apoptosis and inhibited Akt phosphorylation in glioblastoma cell lines. Moreover, Har-hc had the ability to inhibit self-renewal and promote differentiation of glioblastoma stem like cells (GSLCs) accompanied by inhibition of Akt phosphorylation. Especially, we demonstrated that Har-hc inhibited neurosphere formation of human primary GSLCs. In vivo test also confirmed Har-hc decreased the tumorigenicity of GSLCs. Thus we conclude that Har-hc has potent anti-cancer effects in glioblastoma cells, which is at least partially via inhibition of Akt phosphorylation. Administration of Har-hc may act as a new approach to glioblastoma treatment.

Overview of image-guided radiation therapy

Radiation therapy has gone through a series of revolutions in the last few decades and it is now possible to produce highly conformal radiation dose distribution by using techniques such as intensity-modulated radiation therapy (IMRT). The improved dose conformity and steep dose gradients have necessitated enhanced patient localization and beam targeting techniques for radiotherapy treatments. Components affecting the reproducibility of target position during and between subsequent fractions of radiation therapy include the displacement of internal organs between fractions and internal organ motion within a fraction. Image-guided radiation therapy (IGRT) uses advanced imaging technology to better define the tumor target and is the key to reducing and ultimately eliminating the uncertainties. The purpose of this article is to summarize recent advancements in IGRT and discussed various practical issues related to the implementation of the new imaging techniques available to radiation oncology community. We introduce various new IGRT concepts and approaches, and hope to provide the reader with a comprehensive understanding of the emerging clinical IGRT technologies. Some important research topics will also be addressed.