Home > General Information > Abstract    Nanomedicine in Oncology: global status and perspective Nanotechnology and nanomedicine are relatively new fields of scientific research. Nanotechnology has been used to describe research that involves the structure of anything below 100 nanometers in size. Nanomedicine consists of the application of nanotechnologies to human health including ex-vivo diagnostic tools (DNA chips, protein chips), molecular imaging, and the use of smart in vivo devices for physiological monitoring from molecules to electrophysiology, as well as therapeutic tools including nanovectors for drug delivery or micro/nanotools for surgery. Nanomedicine also includes the new understanding of human patholophysiology using all these innovative tools which will be crucial to individualize new therapeutical modalities. We are still practicing medicine using theoretical framework adopted more than 2 centuries ago, using so called anatomo-clinical medicine. Symptoms, physical signs as well as the connected radiological images bring us to the pathological location: If necessary, surgery or biopsy provides us the precise anatomopathological diagnosis after microscopic examination. An adequate therapy is then delivered, whose efficacy is monitored by the same macroscopic and microscopic indicators, including clinical symptoms, physical examination and radiological imaging. In oncology chemotherapy, radiotherapy and surgery remains the standard therapy, and we still wait disease recurrence to know if therapy was effective. Early diagnosis, therapeutical response prediction and monitoring are a major application fields for nanotechnologies. Nanotechnology provides a miniaturization, increasing sensitivity thanks to photolithography, cantevilar detection or the use of nano-reporter for exemple. This increase in sensitivity as well as the integration of sample processing in lab-on chips is major opportunity for the finding and validation of better and innovative biomarkers. Nanoparticles have been already used to increase the sensitivity of classical imaging modalities but also to implement molecular imaging in vivo. Strategies for a non invasive in vivo functional imaging have been validated for exemple for apoptosis or proliferation providing feasibility to characterize the molecular targets in absence of biopsy and to monitor the molecular and cellular pathway triggered by a specific therapy. Therapy benefited also from nanoparticles, providing a better specific targeting of therapeutical agents, crossing-over physiological barriers and with an increased concentration in tumor tissues. Innovative vectors have been validating bringing similar efficacy compared to virus. Smaller tools for diagnosis mean lower invasivity, and fewer side-effects, supporting the innovative concept of nano-invasive diagnosis. Detection of a smaller disease makes it more accessible to therapy because smaller. Nanomedicine not only implies a different dimension level compared to the macro/microsized classical anatomo-pathological medicine. It also implies new paradigms for diagnosis moving from histological to molecular paradigms such as transcriptomic or proteomic profiles. The validation of these molecular tools and their better efficacy for diagnosis, prognostic evaluation and to predict therapeutic response or bring out new curative strategies has been shown especially in oncology. To date, these molecular tools have been applied to macroscopic diseases, demonstrating that anatomopathological analysis can be supplemented by molecular analysis. Early detection means that the disease will be detected at molecular size before becoming macroscopic. This implies the conception of future "smart devices" devoted to in vivo nanodetection and therapy as well as imaging monitoring. Nanomedicine implies also the introduction of personalized medicine, simply meaning the prescription of specific therapeutics best suited for an individual based on pharmacogenetic and pharmacogenomic information. The introduction of pharmacogenomics into clinical trials is reducing the chances of failed clinical trials and increasing the prospects of safer and more effective therapies for specific groups of patients. Nanolevel disease detection and therapy alters medical philosophy and practice and generates some ethical concerns. Ethical concerns are preceded by a fundamental epistemological issue. Is the concept of nanodisease valid: are we sure that the molecular abnormalities proceeding macrodiseases are always followed by pathological states? We must first validate molecular profiles with robust pathological meaning and to eliminate carefully reversible molecular abnormalities. For example, in systematic autopsy in women more than 40 years old a much higher percentage of breast cancers was reported than actually clinically detected. This means that numerous cancerous cells are eliminated in so called healthy women. Initiation of antitumoral therapy at that stage would be a mistake. We will need to validate a specific signature for “resistant” cancerous cells in the organism. In other words, we will have to re-invent a new nano-patho-semiology. Application of nanomedicine concepts not fully validated would be a dangerous mistake. The validation process begins with technological validation. Any technology used at the bedside needs to be unquestionable. For these reasons many recent papers have questioned the validity of DNA and protein chips. The validation process also includes prospective validation in a significant number of patients. This is time and cost consuming and requires much more energy than, for example, the publication of a specific molecular profile in 30 to 40 patients. Thus, the demonstration of the concept of nanomedicine has to be done carefully in prospective trials, which should be, in an optimistic view, supported by the decreased in cost also provided by nanotechnology translated at the industrial level. The main ethical issues are related to the problem of disease detection in "healthy patients", the non medical use of nanotechnologies, and at least some acceptance of what could be potentially uncontrollable modifications of the human body and society. In conclusion, applications of nanotechnologies to oncology open crucial perspectives for a better diagnosis and therapy. This modification in pathological level from macro to nanodisease, which is intrinsic to a better efficacy, also necessitates a major conceptual modification of our current medical practice. Early detection means, in classical macromedical words, "disease therapy before the disease" and may generate potential patient and public misunderstanding from absence of freedom to eugenic suspicion. To avoid irrational reactions, it will be crucial to inform public about the state of the art in nanomedicine and about the existing regulations highly protective for society as well as individual. Supporting to continue investment and research in this field, nanomedecine is already validated at the bedside, strongly demonstating the emergence of a new medical practice based on new epistemological relationship with the illness wich should be compared to the anatomo-clinical revolution several centuries ago.