I attended the 2nd Annual conference of Japanese Society for Molecular Imaging held on 28th and 29th June 2007 at Fukui, Japan. This was the second time a major conference was held here at Fukui, my present city of abode. We were the organizers cum hosts of this meeting and my chief supervisor Prof. Fujibayashi is the president of the society. Though this society is still in infancy celebrating its first anniversary this year, the growth and interest were felt overwhelming among the researchers. The first day morning comprised of symposium sessions from the eminent speakers of US and Europe. The opening keynote lecture by Dr. Jurie Gelovani (University of Texas, MD Anderson Cancer center) was on ‘molecular-genetic imaging in cancer diagnosis and therapy’. He stressed on the importance of developing effective strategies to image tumor biomarkers in facilitating early and accurate diagnosis. Imaging can not only play a major role in tumor profiling but also in therapy assessment in terms of dose, duration and tumor prognosis. He also presented the evaluation of fluoroacetate-PET in multitumor model conducted in rats and EGFR expression by PET imaging. The recent research progress on imaging the activity of HDAC (using Fluorine-18 labeled FAHA) in tumors was quite interesting. The dynamic biodistribution of PET radiotracer over the entire duration of emission scan was highly impressive. Progress in myocardial stem cell implant and imaging by HSV-tk expression was also mentioned. His forecast for the future imaging strategies included multiple radiotracers for imaging tumor-specific tissue biomarkers (‘imageable biomarkers’), development of more C-11 tracers, more sensitive PET systems with longer Z-axis and use of PET/MRI or PET/CT+MRI imaging systems.
The title of next speaker Dr. Timothy J McCarthy (from Pfizer R&D) was ‘Imaging as a key enabling tool in drug development’. He emphasized particularly on how molecular imaging plays a key role in new drug development and evaluation. Few examples given were discovery and validation of a PET tracer for the 5-HT1B-receptor, F-18 labeled galacto-RGD tracer evaluation for tumor imaging, checkpoint kinase inhibition by FLT, development and evaluation of sutent in tumor treatment and MR image contrast mechanisms (imaging methemoglobin) in various diseases. He also highlighted about the importance of upcoming Joint Molecular Imaging Conference in this year and emphasized that partnerships at all levels are critical to the future of molecular imaging.
The third speaker was Dr. Hisataka Kobayashi (National Cancer Institute, NIH), who spoke on ‘Multiplexed in vivo cancer imaging’. Initially he described the current status of molecular imaging in NIH (USA). Molecular Imaging forms one of the five NCI 2015 core projects (others are Genomic, Proteomic, Molecular targeting and Nanotechnology). He also mentioned salient features from Dr. Zerhouni’s lecture on ‘Bioscience in 21st century’ from NIBIB’s fifth anniversary symposium. His talk focused on multi-parametric imaging where in multi-color probes, activatable “smart” agents and multi-modal agents can be utilized. Using 2-color fluorescent probes, both time and spectrally resolved dynamic image can be simultaneously obtained. Use of pH sensitive probes (activatable GSA-BDP) enabling targeted tumor imaging even in the presence of ascites was well demonstrated.
The next talk by Dr. J.L. Coll (University of Grenoble, France) was on molecular imaging in the European community specifically focused on optical imaging strategies for detection, medical imaging and cancer treatment. He described the attributes of regioselectively addressable functionalized template (RAFT) presenting four cyclic RGD peptides linked to Cy5 (a fluorescence quencher) as an effective probe for imaging tumors and in vivo RGD-mediated internalization. He also highlighted the utility of 2D-fluorescence reflectance imaging (FRI) and 3D imaging in vivo using fluorescence diffuse optical tomography (FDOT).
The evening plenary talk was delivered by Dr. Roderic I Pettigrew (Director, NIBIB). He stressed the future of molecular medicine depends on developments occurring in three core fields – genomics, nanotechnology and bioimaging systems analysis. Current molecular imaging technologies can detect molecular complexes, proteins, enzymes and even gene expression but little it can do in delineating intracellular molecular movement, transient assemblies and temporal-spatial relationships. Few interesting research findings discussed were – use of molecular beacons to view tadpole “tail” mRNA migration, multi-isotope mass spectrometry imaging which provides high resolution imaging of protein metabolism, control of sweet preference in transgenic mice at the level of sweet taste receptors, photonic crystal tear glucose sensing, MR guided optical fluorescence measurement and so on. Probe sensitivity needs to be amplified to label individual molecules or detect individual molecular events in single cells and in the order of 1000-fold to that of original signal. He also highlighted that the future research perspective should aim at focusing on system of targets (not a target) and understanding disease pathways in terms of fundamental disease mechanisms such as inflammation, protein action, apoptosis or cell signaling. There is also a need for more precise, quantitative and accessible new research tools such as animal models, novel probes, preclinical biomarkers and targeted delivery systems.
In the evening banquet ceremony, I was surprised and elated to know that my poster was awarded as one of the three best posters in the current meeting. It was a glorious moment worth cherishing for a long time to come when I received the award by none other than my chief supervisor, Prof. Fujibayashi.
In the next day , there were some interesting presentations from eminent Japanese researchers. Dr. Okano Hideyuki of Keio University presented “Imaging techniques in regenerative medicine”, where in he discussed the mechanisms of regeneration of neurons by neuroblast activation. Visualization of CSF flow can be facilitated by using 7.4 Tesla MRI and Mn2+ ion. Visualization of CNS tracts in the intact cervical spinal cord of marmosets using diffusion tensor tractography was also demonstrated which could be applicable to real time evaluation of axonal degeneration. The use of bioluminescence imaging for quantitative assessment of estrogen dependent growth was also discussed.
Dr Takahiro Ochiya of National Cancer Research Institute delivered lecture on “imaging molecular targets for cancer therapy” where in he elaboratively described interference (RNAi), siRNA/atelocollagen complex and various microRNA (miRNA) groups currently discovered as molecular targets for cancer therapy.
The talk by Dr Eiji Kobayashi of Jichi medical university was titled “In vivo imaging using dual colored Tg rats for innovative medical research”. His group have developed various colored Tg rats (of different fluorescence or luminescence) using transgenic technology. Many other oral sessions were also stimulating but couldn’t comprehend completely due to language barrier. Overall, the 2nd JSMI meeting was a successful outcome especially with our group being the hosts of the big event.
