RESUMO
Head and Neck Squamous Cell Carcinoma (HNSCC) remains a cancer with a poor prognosis, with a 5-year survival rate of less than 50%. Although epidermal growth factor receptor (EGFR) is almost always overexpressed, targeted anti-EGFR therapies have modest efficacy and are mainly used in palliative care. Growth factors such as Nerve Growth Factor (NGF) and its precursor proNGF have been shown in our laboratory to play a role in tumor growth and aggressiveness. Interestingly, an interaction between Sortilin, a proNGF receptor, and EGFR has been observed. This interaction appears to interfere with the pro-oncogenic signaling of EGF and modulate the membrane expression of EGFR. The aim of this study was to characterize this interaction biologically, to assess its impact on clinical prognosis and to analyze its role in the cellular trafficking of EGFR. Using immunohistochemical staining on tumor sections from patients treated at our university center and PLA (Proximity Ligation Assay) labeling, we showed that Sortilin expression is significantly associated with reduced 5-year survival. However, when Sortilin was associated with EGFR, this association was not found. Using the Cal-27 and Cal-33 cancer cell lines, we observed that proNGF reduces the effects of EGF on cell growth by inducing the internalization of its receptor. These results therefore suggest a regulatory role for Sortilin in the degradation or renewal of EGFR on the membrane. It would be interesting in future work to show the intracellular fate of EGFR and the role of (pro)neurotrophins in these mechanisms.
RESUMO
Intranasal corticosteroid drugs are widely used in chronic rhinosinusitis with nasal polyps (CRSwNP). In contrast to classical delivery with nasal pump sprays, pulsating aerosols can deliver significant doses into superior and posterior sinonasal spaces. A case-control study was designed to assess the efficacy of corticosteroid transnasal nebulization on short-term mucosal recovery and quality of life (QoL) following endoscopic sinus surgery in CRSwNP. Thirty patients were prospectively enrolled to receive either 1-month budesonide nasal pump spray or 1-month budesonide 100-Hz acoustic pulsating nebulization at the first postoperative visit (day 8). Patients were evaluated with Lund-Kennedy endoscopic score at day 8 (D8) and 1 month later (M1). CRS-related QoL questionnaires (SNOT22 and RhinoQOL) were fulfilled at M1. The Lund-Kennedy endoscopic scores compared between D8 and M1 were suggestively improved in the group treated with budesonide nebulization (mean difference between groups, - 18.28 units; 95%CI, - 31.29 to - 5.28 units, p = 0.014). QoL measurements were comparable at M1 between the groups of patients. No unexpected adverse event was described with both budesonide delivery protocols. In the early postoperative period, patients with CRswNP may benefit from pulsating nebulization. Large studies should be conducted to confirm the results. Safety profile related to systemic steroid absorption and bioavailability in chronic respiratory diseases also need to be addressed for further use.