The main aim of the present project is to contribute to the improvement of diagnostic and prognostic routine methodologies for Head and Neck Squamous Cell Carcinoma (HNSCC).
The identification of predictive early biomarkers from blood-derived Circulating Tumour Cells (CTCs) combined with non-invasive methodology, like liquid biopsy is crucial for patients screening and represent a powerful platform for future personalized therapy to improve survival rate and decrease the incidence of recidivating tumours.
Unfortunately, no prognostic markers are currently available for HNSCC because of low number of CTCs and low sensitivity and false negative results arising from traditional approaches based on surface adhesion molecules, including EpCAM, citokeratin and beta-catenin.
To overcome these limitations, we propose the development and validation of TripleQuad/SelexION-based high-throughput and high-sensitivity mass spectrometry approaches to implement the analytical and regulatory detection of key determinants in blood derived CTCs from HNSCC.
Based on our previous works and current literature, we hypothesize that the receptors for the mature nerve growth factor (NGF) and its precursor form (proNGF), namely p75 neurotrophic receptor (p75NTR) and Tyrosine kinase A (TrkA), are involved in cancer cells survival, proliferation, and spreading, and represent a promising marker in squamous tumour, like HNSCC.
In line with this working hypothesis, our preliminary results showed increased level of p75NTR and of cancer-associated TrkA variant TrkAIII in tumour tissues from a small group of LSCC patients, as compared to the healthy controls.
Overall, based on the promising data hereby collected, and combining classical biochemical methods with the most advanced proteomic analysis, we envisage a significant correlation between NGF receptor variants with tumour aggressiveness, pinpointing their potential as specific and novel blood biomarkers for HNSCC personalized therapy.
Unlikely the HNSCC, the squamocellular carcinoma that affect different parts of the patients bodies (i.e. skin) can be detected and monitored because the related specific diagnostic, prognostic and follow-up markers have been found. Therefore, the identification of head and neck tumoral specific markers, as well as the hypothesis of the potential involvement of neurotrophins in that process, might represent per se a great innovative tool in clinical and research fields to improve the detection of HNSCC and the condition of patients affected by the pathology.
Specifically:
1. The hypothesis that p75NTR cleavage and TrkAIII might be involved in the regulation of CSCs survival and behaviour leads to a new prospect in terms of managing the pathology, predicting tumoral progression using the liquid biopsy, and improving the quality of patient¿s life even when affected by a late tumoral stage.
2. The prospect that the NGF specific pathway is an accurately regulated process in physiological and pathological epithelium, detecting the p75NTR and TrkA mediated signal by the inhibition and/or the use of specific enzymes, could represent a novel and promising approach to squamocellular carcinoma therapy.
3. The proteomic-quantitative profile of p75NTR fragments and TrkA in rare cellular populations, as the CTCs, in limited volume of physiological fluid using the integrated platform TripleQuad/SelexION (SCIEX) will allow the high sensitive and specific analysis of hundreds of samples compared to the traditional technology.
4. The chance that TrkAIII isoform might promote the detection of the HNSCC patient¿s profile could potentially lead to novel understandings of early diagnosis as well as to the identifications of new agents specific to the therapy.
5. This last point seems to be greatly relevant in order to open new perspectives related to genetic and epigenetic studies related to HNSCC research, which are, at now, still poorly investigated.
6. In addition, since the standard isolation of CTCs by EpCAM, cytokeratine, and ß-catenin show false negatives, bringing to critical limitations in studying CTCs/CSCs ratio in HNSCC, the validation of a novel isolation method based on the expression of NGF and its receptors in CSCs/CTCs could serve as an efficient enrichment of CTCs from blood, and potentially provide new analytes to implement liquid biopsy in head and neck cancer. Indeed, at present, there is a lack of prognostic and predictive markers for HNSCC, and the use of liquid biopsy is limited to Epstein-Barr virus (EBV) and papillomavirus (HPV) detection.