HypoSens is strategically designed to offer a minimally-invasive alternative to the Sentinel Lymph Node Biopsy, the current surgical procedure for breast cancer staging.
Cancer metastasis occurs when highly aggressive tumour cells escape from the primary tumour mass and travel through the blood and/or lymphatic systems towards a target organ. In particular, breast cancer metastasis develops mostly via the lymphatic system. The lymph node that is closest to the tumour is called the sentinel lymph node (SLN). Diagnosing the presence of cancerous cells within the SLN is therefore critical for patient stratification, accurate prognosis, and for providing optimum treatment plans.
Currently, the SLN is identified by injecting dyed radionuclide tracers near the tumour. These tracers accumulate in the SLN and are detected visually and/or with a device that detects radioactivity. The sentinel node is removed (SLN biopsy (SLNB)) and checked for cancer cells by histopathological analysis, which can take up to 2 weeks. A negative SLNB result suggests that cancer has not spread to other organs. A positive SLNB result indicates potential metastasis to regional lymph nodes and potentially to other organs. This is considered a strong predictor of recurrences and survival, and help oncologists to diagnose the cancer stage, give some prognostic indications, and define the appropriate treatment schedule.
However, current SLNB procedure is invasive, induces allergies or lymphedema, requires skilled clinical personnel, is quite expensive, and takes about 2 weeks of time to render results. All these facts negatively impact the patients, the oncologists and other health professionals, and the public health system.
The HypoSens prognostic system consists of a minimally-invasive near-infrared (NIR) device able to register signals through the skin, that process data collected by tumour-targeted nanoparticles containing specific sensors able to determine local oxygen (O2) concentration and local temperature (T) distribution in the SLN.
The initial target of the project is metastatic breast cancer, with potential later involvement in other cancer indications via the use of different tumour-targeting moieties.
The technical objectives for the HypoSens project were:
• To design organic molecules to serve as T & O2 sensing tools; and to develop enhanced synthesis, encapsulation and decoration processes to produce necessary amounts of nanoconfined sensors.
• To design, develop, construct, and optimize an ultra-sensitive and time-resolved all-optical ratiometric sensing technique for local T and local O2 level measurement.
• To validate the nanosensors and the photonic device on preclinical in vitro and in vivo tumour xenograft models, and on clinical SLNB ex vivo.
After 36 months of execution, HypoSens project has overcome difficult scientific and technical challenges, being able to fulfil most of the initial goals. Importantly, HypoSens nano-confined sensing system is the first of its kind to simultaneously monitor local T and O2 concentration from a single object after injection in mouse models. Furthermore, the fact that HypoSens employs tumour-targeted technologies opens a wide spectrum for future market applications of the biophotonics imaging system.
