RESUMEN
Infection with human papillomaviruses (HPVs), in particular with HPV type 16, is now considered to be a key risk factor for the development of a subset of oropharyngeal squamous cell carcinomas (OPSCC) that show different epidemiological, clinical, and prognostic characteristics from HPV-negative (HPV-) OPSCCs. So far, extensive research efforts aiming to distinguish these two distinct entities have not identified specific biomarkers, nor led to different therapies. Previous research has shown that HPV16 E6 oncoprotein binds NHERF2, inducing its proteasomal degradation, and consequently increasing cell proliferation; we therefore aimed to investigate how this might be reflected in human histological samples. We analyzed NHERF2 expression patterns in HPV16-positive (HPV16+) and HPV- OPSCC samples, to investigate any potential differences in NHERF2 pattern. Interestingly, we observed a statistically significant decrease in NHERF2 levels in HPV16+ and poorly differentiated HPV- OPSCCs, compared with healthy tissue. Furthermore, we observed a significant reduction in the percentage of NHERF2 immunoreactive cancer cells in HPV16+ tumors, compared with well and moderately differentiated HPV- OPSCCs, suggesting the importance of 16E6's targeting of NHERF2 in HPV-driven oncogenesis in the head and neck area.
RESUMEN
The aim of this work was to explore the application of sulfate radical based advanced oxidation processes: photooxidation (UV/PMS/PS), sonooxidation (US/PMS/PS) and combined sono-photooxidation (US/UV/PMS/PS) for the mineralization of simulated dyehouse effluent (WW); using peroxymonosulfate (PMS) and persulfate (PS) as oxidants. Experiments were performed in a reaction vessel of a defined geometry and axially positioned source of UV-C radiation, all placed in the ultrasonic bath (35 kHz). Mathematical model of the process was developed according to the proposed degradation scheme. Decomposition of dyestuff (C.I. Reactive Violet 2, RV2 and C.I. Reactive Blue 7, RB7), surfactant (linear alkylbenzene sulfonate; hereafter: LAS) and auxiliary organic components was explored in three types of model wastewater: WW, simulated effluent excluding inorganic species (WW-IS) and model solution that consists of a specific compound (hereafter: compound model solutions). The influence of inorganic matrix (Cl(-), CO(3)(2-)/HCO(3)(-)) was studied due to the corresponding quenching affinity toward HO and SO(4)(-) radicals. The efficiency of applied processes was evaluated and the response to combined phenomena (cavitation and irradiation) was quantified as synergy index, f(Syn). Sono-photooxidative treatment (US/UV/PMS/PS) of WW resulted in a partial mineralization and partial decolourization; approximately 40% of initial TOC and 30% of initial RB7 remained after 60 min of treatment, while RV2 and LAS molecule were completely decomposed. Circumstantially, the combined process increased the mineralization efficiency by a factor of 3 (f(Syn) = 3.026).
