Structural insights into non-hotspot KRAS mutations and their potential as targets for effective cancer therapies.

Kirsten rat sarcoma virus protein (KRAS) is a protein that plays a central role in signal transduction using extracellular signal regulated kinase (ERK) and mitogen activated protein kinase (MAPK) cellular signaling pathway. KRAS is a frequently mutated oncogene and plays a pivotal role in tumor initiation and progression. Hotspot mutations on codon 12, 13 and 61 in KRAS are well-known for their role in drug resistance and non-hotspot mutations also play a significant part in contributing to resistance mechanisms. The understanding of how these non-hotspot mutations might affect the signal transduction of KRAS and their contribution towards drug resistance is understudied. Here we provide structural insights into the interaction of non-hotspot KRAS mutants with GTP (the native ligand) using a molecular docking and molecular dynamics simulation approach. Extensive molecular docking and simulation studies suggest that non-hotspot mutations (E31D and E63K) show stable interaction with native ligand using all five trajectories, as evidenced by root mean square of distance (RMSD), root mean square of fluctuation (RMSF), radius of gyration (RoG), coulomb short-range energy and MMGBSA analysis. These results suggest that non-hotspot mutations do not undermine the oncogenic nature of KRAS. This observation is consistent with previous findings where overexpressing E31D and E63K mutations share phenotypic features with G12D and G13D transfected cells, including increased proliferative capacity, actin cytoskeleton organization, and migration rates. We further test whether FDA-approved KRAS inhibitors sotorasib and adagrasib successfully inhibit the E31D and E63K mutants. Results suggest that these two non-hotspot mutants can be inhibited by both drugs with following trend of structural stability (E31D > E63K > wild-KRAS > Q61H > G12C). Based on sharp coherence in trajectories between wild KRAS and non-hotspot mutants, it is suggested that these novel mutants do not contribute to drug resistance mechanism. Overall, we provide a comprehensive understanding of the impact of non-hotspot mutations on KRAS and their potential as targets for effective cancer therapies.Communicated by Ramaswamy H. Sarma.

The EEG Oscillations and Psychology Propensities of Autonomous Sensory Meridian Response.

Autonomous sensory meridian response is believed as a perceptual phenomenon to specific sensory stimuli. To explore the underlying mechanism and emotional effect, the EEG under video and audio triggers of autonomous sensory meridian response was analyzed. The differential entropy and power spectral density by Burg method on δ, θ, α, ß, γ and high γ frequencies were employed as quantitative features. The results indicate that the modulation of autonomous sensory meridian response on brain activities is broadband. Video trigger owns better performance of autonomous sensory meridian response than other triggers. Moreover, the results also reveal that autonomous sensory meridian response has a close relationship with neuroticism and its three sub-dimensions, anxiety, self-consciousness and vulnerability, with the scores of self-rating depression scale, but without emotions, happiness, sadness, or fear. This suggests that the responders of autonomous sensory meridian response may have the tendencies of neuroticism and depressive disorder.

Ferulic acid attenuates high glucose-induced apoptosis in retinal pigment epithelium cells and protects retina in db/db mice.

Background: Herein, we aimed to present evidence that Ferulic acid (FA), a phenolic acid, can alleviate high glucose (HG)-induced retinal pigment epithelium (RPE) cell apoptosis and protect retina in db/db mice. Methods: ARPE-19 cells (a human RPE cell line) were divided into four groups: control group; HG group (30 mmol/L glucose); HG+FA group (30 mmol/L glucose and 10 mmol/L FA). Cell viability and apoptosis were detected using CCK-8 and Annexin-5 staining, respectively. Apoptosis-related markers including P53, BAX and Bcl2 were examined by RT-qPCR, western blot and immunohistochemistry. Totally, 30 male db/db mice were randomly divided into db/db group (5 ml/kg saline) and FA group (0.05 g/kg FA). After treatment for 2 months, retinal samples were subjected to hematoxylin and eosin (H&E) and Masson staining. Moreover, immunofluorescence was used to detect apoptosis-related markers. Blood samples were collected for measuring cholesterol, triglyceride (TG), low-density lipoprotein (LDL) and high-density lipoprotein (HDL) levels. Results: FA treatment markedly increased cell viability and suppressed cell apoptosis of ARPE-19 cells compared to the HG-exposed group. Furthermore, FA ameliorated the abnormal expression levels of P53, BAX and Bcl2 in HG-induced ARPE-19 cells. In animal models, FA attenuated pathological changes in the retina tissues of diabetic mice. Consistent with in vitro models, FA significantly ameliorated the expression of apoptosis-related markers in retina tissues. Biochemical test results showed that FA reduced hyperlipidemia in diabetic mice. Conclusion: Our findings suggest that FA alleviates HG-induced apoptosis in RPE cells and protects retina in db/db mice, which can be associated with P53 and BAX inactivation and Bcl2 activation.

Expression Profiles and Prognostic Value of Multiple Inhibitory Checkpoints in Head and Neck Lymphoepithelioma-Like Carcinoma.

Background: Inhibitory checkpoints are promising antitumor targets and predictive biomarkers in a variety of cancers. We aimed to identify the expression levels and prognostic value of multiple inhibitory checkpoints supported by preclinical and clinical evidence in head and neck lymphoepithelioma-like carcinoma (HNLELC). Methods: The expression of seven inhibitory checkpoints were evaluated in the tumor nest (TN) and tumor stroma (TS) of 102 HNLELC specimens using immunohistochemistry and digital pathology, and an inhibitory checkpoint-based signature (ICS) was subsequently constructed using the LASSO Cox regression model. Results: PD-L1, B7H3, and IDO-1 were mostly expressed in the TN, with median H-score of TN vs TS: 63.6 vs 14.6; 8.1 vs 1.0; 61.5 vs 34.7 (all P < 0.001), whereas PD-1, TIM-3, LAG-3, and VISTA were mainly observed in the TS, with median H-score of TN vs TS: 0.2 vs 12.4, 3.4 vs 7.1, 6.2 vs 11.9, 16.4 vs 47.2 (all P < 0.001), respectively. The most common simultaneously expressed combinations consisted of PD-L1 + B7H3 + IDO-1 + TIM-3 + LAG-3 + VISTA and B7H3 + IDO-1 + TIM-3 + LAG-3 in the TN (both occurring in 8.8% of patients) and PD-L1 + B7H3 + IDO-1 in the TS (4.9%). In addition, high-ICS patients had shorter 5-year disease-free (40.6% vs 81.7%; P < 0.001), regional recurrence-free (63.5% vs 88.2%; P = 0.003), and overall survival (73.5% vs 92.9%; P = 0.006) than low-ICS patients. Multivariate analysis revealed that ICS represented an independent predictor, which could significantly complement the predictive performance of TNM stage for 3-year (AUC 0.724 vs 0.619, P = 0.014), 5-year (AUC 0.727 vs 0.640, P = 0.056), and 10-year disease-free survival (AUC 0.815 vs 0.709, P = 0.023). Conclusions: The expression of inhibitory checkpoints and ICS classifier may increase the prognostic value of the TNM staging system and guide the rational design of personalized inhibitory checkpoint blockade therapy in HNLELC.

Epstein-Barr virus microRNA BART10-3p promotes dedifferentiation and proliferation of nasopharyngeal carcinoma by targeting ALK7.

Non-keratinizing nasopharyngeal carcinoma, the major subtype of nasopharyngeal carcinoma, is characterized by low differentiation and a close relation to Epstein-Barr virus infection, which indicates a link between Epstein-Barr virus oncogenesis and loss of differentiation, and raises our interest in investigating the involvement of Epstein-Barr virus in nasopharyngeal carcinoma dedifferentiation. Our previous study showed abundant expression of an Epstein-Barr virus-encoded microRNA, BART10-3p, in nasopharyngeal carcinoma tissues, but the association between BART10-3p and nasopharyngeal carcinoma differentiation remains unknown. Here, we examined the expression and prognostic value of BART10-3p, and undertook bioinformatics analysis and functional assays to investigate the influence of BART10-3p on nasopharyngeal carcinoma differentiation and proliferation and the underpinning mechanism. Microarray analysis identified BART10-3p as the most significantly upregulated Epstein-Barr virus-encoded microRNA in nasopharyngeal carcinoma tissues and the upregulation was confirmed in two public datasets. The expression of BART10-3p was an independent unfavorable prognosticator in nasopharyngeal carcinoma and its integration with the clinical stage showed improved prognosis predictive performance. Bioinformatics analysis suggested a potential role of BART10-3p in tumor differentiation and progression. Functional assays demonstrated that BART10-3p could promote nasopharyngeal carcinoma cell dedifferentiation, epithelial-mesenchymal transition, and proliferation in vitro, and tumorigenicity in vivo. Mechanistically, BART10-3p directly targeted the 3'UTR of ALK7 and suppressed its expression. Reconstitution of ALK7 rescued BART10-3p-induced malignant phenotypes. Overall, our study demonstrates that BART10-3p promotes dedifferentiation and proliferation of nasopharyngeal carcinoma by targeting ALK7, suggesting a promising therapeutic opportunity to reverse the malignant phenotypes of nasopharyngeal carcinoma.

Combining tumor response and personalized risk assessment: Potential for adaptation of concurrent chemotherapy in locoregionally advanced nasopharyngeal carcinoma in the intensity-modulated radiotherapy era.

BACKGROUND AND PURPOSE: In the intensity-modulated radiotherapy (IMRT) era, the role of concurrent chemoradiotherapy (CCRT) after induction chemotherapy (IC) in locoregionally advanced nasopharyngeal carcinoma (LANPC) is undetermined, while concerns exist about CCRT-associated excessive toxicity. We aimed to combine tumor response and risk assessment to guide decisions about concurrent chemotherapy. MATERIALS AND METHODS: From April 2009 to December 2015, 744 LANPC patients treated with CCRT/IMRT after IC were included. Matching techniques were performed for treatment effect evaluation. Tumor response to IC was used for patient stratification. A nomogram was built based on multivariable Cox regression analysis to predict overall survival (OS). RESULTS: After IC, 508 patients (68.3%) had favorable tumor response (complete or partial response), among whom IC + CCRT achieved significantly superior 5-year disease-free survival and OS than IC + IMRT (82.2% vs. 72.5%, P = 0.025; 89.2% vs. 79.9%, P = 0.025). However, no significant difference was found in patients with unfavorable response (both P > 0.05). For favorable responders, a nomogram was built integrating age, smoking, T category, N category, pretreatment Epstein-Barr virus DNA and treatment modality. The concordance index was 0.713 and calibration was good. The nomogram determined three risk groups with distinct OS. High-risk patients benefited from CCRT after IC regarding disease-free survival, OS and distant metastasis-free survival, whereas low- and intermediate-risk patients did not. CONCLUSIONS: For LANPC patients with unfavorable response to IC, subsequent CCRT seems inadequate, rendering intensification necessary. For favorable responders with low risk, IC + IMRT represents a reasonable de-intensification approach, although confirmation by prospective data is needed.

Prevalence and associated factors of corneal blindness in Ningxia in northwest China.

AIM: To describe the prevalence and demographic characteristics of corneal blindness in an urban and rural region of Ningxia, located in the northwest part of China. METHODS: A stratified, randomized sampling procedure was employed in the study, including urban and rural area of all age group. Visual acuity, anterior segment and ocular fundus were checked. Related factor of corneal disease, including age, gender, education status, ethnic group, location and occupation, were identified according to uniform customized protocol. An eye was defined to be corneal blindness if the visual acuity was <20/400 due to a corneal disease. RESULTS: Three thousand individuals (1290 from urban area and 1710 from rural area) participated in the investigation, with a response rate of 80.380%. The prevalence of corneal blindness was 0.023% in both eyes and 0.733% in at least one eye. The blindness in at least one eye with varied causes was present in 106 participants (3.533%) and in bilateral eyes in 34 participants (1.133%). The corneal diseases accounted for 20.754% of blindness in at least one eye and 20.588% of bilateral blindness. The prevalence of corneal disease was higher in older and Han ethnic group, especially those who occupied in agriculture and outdoor work. People with corneal blindness were more likely to be older and lower education. Rural population were more likely to suffer from bilateral corneal blindness than the urban population in ≥59-year group (χ (2)=6.716, P=0.019). Infectious, trauma and immune corneal disease were the three leading causes of corneal disease. Trauma corneal disease was more likely leading to blindness in one eye. However, infectious and immune corneal diseases make more contribution to the bilateral corneal blindness. CONCLUSION: Corneal blindness is a significant burden of in Ningxia population, encompassing a variety of corneal infections and trauma; the majority of those were avoidable. Health promotion strategies and good hygienic conditions have to be developed.