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Background: Transoral surgery (TOS) has been widely applied for early T‐stage head and neck cancer (HNC). The resection is performed with a minimum safety margin for function preservation under a limited surgical field; therefore, it is difficult to have a strong conviction about the complete resection. This study aims to evaluate the completeness of the initial TOS procedure; possibility of primary control by TOS alone; and predictive factors in patients with early T‐stage laryngeal, oropharyngeal, and hypopharyngeal cancer. Methods: Patients were treated by TOS at the primary site with or without neck dissection. The patients were divided into two groups based on the pathological evaluation of their surgical specimens: the control (observation) group, in that the resection was considered complete and the intervention (second‐look procedure) group, in that incomplete tumor resection was suspected. The predictive factors for the possibility and/or limitations of complete resection by TOS were then analyzed. Results: The study enrolled 26 and 25 patients in the control and intervention group, respectively. The success rate for single resection was 66% and the predictive factor was tumor depth obtained by enhanced computed tomography (CT) examination (odds ratio, 7.870, P = .0243). The success rate for definitive therapy by TOS alone was 83% and the predictive factor was poor differentiation observed on pathological examination (odds ratio, 6.800, P = .0248). Conclusions: TOS has the potential for both definitive resection and function preservation with minimal invasiveness. Identification of the risk factors for TOS is advantageous for accurate treatment selection in patients with early T‐stage HNC. [ABSTRACT FROM AUTHOR]

Avicins, a class of electrophilic triterpenoids with pro-apoptotic, anti-inflammatory and antioxidant properties, have been shown to induce redox-dependant post-translational modification of cysteine residues to regulate protein function. Based on (a) the cross-talk that occurs between redox and phosphorylation processes, and (b) the role of Stat3 in the process of apoptosis and carcinogenesis, we chose to study the effects of avicins on the processes of phosphorylation/ dephosphorylation in Stat3. Avicins dephosphorylate Stat3 in a variety of human tumor cell lines, leading to a decrease in the transcriptional activity of Stat3. The expression of Stat3-regulated proteins such as c-myc, cyclin D1, Bcl2, survivin and VEGF were reduced in response to avicin treatment. Underlying avicin-induced dephosphorylation of Stat3 was dephosphorylation of JAKs, as well as activation of protein phosphatase-1. Downregulation of both Stat3 activity and expression of Stat 3-controlled pro-survival proteins, contributes to the induction of apoptosis in avicin treated tumor cells. Based on the role of Stat3 in inflammation and wounding, and the in vivo inhibition of VEGF by avicins in a mouse skin carcinogenesis model, it is likely that avicin-induced inhibition of Stat3 activity results in the suppression of the proinflammatory and pro-oxidant stromal environment of tumors. Activation of PP-1, which also acts as a cellular economizer, combined with the redox regulation by avicins, can aid in redirecting metabolism from growth promoting anabolic to energy sparing pathways. [ABSTRACT FROM AUTHOR]

Avicins are a recently discovered family of plant-derived terpenoid molecules that possess proapoptotic, antiinflammatory, and cyto- protective properties in mammalian cells. Previous work demonstrating that avicins can exert their effects by suppressing or activating the redox-sensitive transcription factors NF-kB and nu- clear factor-erythroid 2 p45-related factor (Nrf2), respectively, has raised the idea that they may react with critical cysteine residues. To understand the molecular mechanism through which avicins regulate protein function, we examined their effects on the paradigmatic redox-responsive transcriptional activator, OxyR of Escherichia coli, which protects bacterial cells against oxidative and nitrosative stresses. In vitro transcription assays demonstrated that avicins activate OxyR and its target genes katG and oxyS in a DTT-reversible manner. In addition, katG-dependent hydroperoxidase I activity was enhanced in avicin-treated bacteria. Mass spectro metric analysis of activated OxyR revealed thioesterification of the critical regulatory cysteine, Cys-199, to an avicin fragment comprising the outer monoterpene side chain. Our results indicate that avicinylation can induce adaptive responses that protect cells against oxidative or nitrosative stress. More generally, transesterification may represent a previously undescribed thiol-directed posttranslational modification, which extends the code for redox regulation of protein function. [ABSTRACT FROM AUTHOR]

Avicins are proapoptotic and anti-inflammatory triterpene electrophiles isolated from an Australian desert tree, Acacia victoriae. The presence of two α,β unsaturated carbonyl groups (Michael reaction sites) in the side chain of the avicin molecule prompted us to study its effects on NF-E2-related factor 2 (Nrf2), a redox-regulated transcription factor that controls the expression of a battery of detoxification and antioxidant proteins via its binding to antioxidant response element (ARE). Avicin D-treated Hep G2 cells showed translocation of Nrf2 into the nucleus and a time-dependent increase in ARE activity. These properties were sensitive to DTT, suggesting that avicins affect one or more critical cysteine residues, probably on the Keapl molecule. Downstream of ARE, an activation of a battery of stress-induced proteins occurred. The implications of these findings were evaluated in vivo in mouse skin exposed to an ancient stressor, UV light. Avicins inhibited epidermal hyperplasia, reduced p53 mutation, enhanced apoptosis, decreased generation of 8-hydroxy-2′-deoxyguanosine, and enhanced expression of NADPH:quinone oxidoreductase 1 and heme oxygenase-1. These data, combined with our earlier published work, demonstrate that avicins represent a new class of plant stress metabolites capable of activating stress adaptation and suppressing proinflammatory components of the innate immune system in human cells by redox regulation. The relevance for treatment of clinical diseases in which stress responses are dysfunctional or deficient is discussed. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the predictive and prognostic value of pretreatment metabolic tumor volume (MTV) in patients with treated by radiotherapy (RT) or concurrent chemoradiotherapy (CCRT). Methods: We reviewed the records of 118 patients with newly diagnosed laryngeal carcinoma, who had been treated by RT or CCRT. Pretreatment positron emission tomography (PET) was performed, and MTV values were obtained by contouring margins of standardized uptake value. Clinical factors and MTV were analyzed for their association with survival. Results: Patients with residual disease showed a significantly higher MTV than those with a complete response (CR) after primary treatment. Univariate analysis showed that the patients with a high MTV had a significantly lower disease-free survival (DFS) (p < 0.001). Subsite (p = 0.010), T-stage (p < 0.001), nodal metastasis (p < 0.001) and clinical stage (p < 0.001) also correlated significantly with DFS. In the multivariate analysis, MTV and clinical stage were both found to be independent prognostic factors for DFS (p = 0.001, p = 0.034, respectively). The 3-year DFS for patients with a high MTV were significantly poorer than those with a low MTV (p < 0.001). Conclusions: MTV of the primary tumor is a significant prognostic factor for DFS in patients with laryngeal carcinoma treated by RT or CCRT. The results imply that MTV could be an important factor when planning treatment and follow-up for patients with laryngeal carcinoma. [ABSTRACT FROM AUTHOR]