RESUMO
Ionizing radiation, a standard therapeutic approach for lung cancer, often leads to cellular senescence and the induction of epithelial-mesenchymal transition (EMT), posing significant challenges in treatment efficacy and cancer progression. Overcoming these obstacles is crucial for enhancing therapeutic outcomes in lung cancer management. This study investigates the effects of ionizing radiation and gemcitabine on lung cancer cells, with a focus on induced senescence, EMT, and apoptosis. Human-derived A549, PC-9, and mouse-derived Lewis lung carcinoma cells exposed to 10 Gy X-ray irradiation exhibited senescence, as indicated by morphological changes, ß-galactosidase staining, and cell cycle arrest through the p53-p21 pathway. Ionizing radiation also promoted EMT via TGFß/SMAD signaling, evidenced by increased TGFß1 levels, altered EMT marker expressions, and enhanced cell migration. Gemcitabine, a first-line lung cancer treatment, was shown to enhance apoptosis in senescent cells caused by radiation. It inhibited cell proliferation, induced mitochondrial damage, and triggered caspase-mediated apoptosis, thus mitigating EMT in vitro. Furthermore, in vivo studies using a lung cancer mouse model revealed that gemcitabine, combined with radiation, significantly reduced tumor volume and weight, extended survival, and suppressed malignancy indices in irradiated tumors. Collectively, these findings demonstrate that gemcitabine enhances the therapeutic efficacy against radiation-resistant lung cancer cells, both by inducing apoptosis in senescent cells and inhibiting EMT, offering potential improvements in lung cancer treatment strategies.
Assuntos
Antimetabólitos Antineoplásicos , Senescência Celular , Desoxicitidina , Transição Epitelial-Mesenquimal , Gencitabina , Neoplasias Pulmonares , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Senescência Celular/efeitos dos fármacos , Senescência Celular/efeitos da radiação , Animais , Humanos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos da radiação , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/metabolismo , Camundongos , Antimetabólitos Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Camundongos Endogâmicos C57BL , Células A549 , Radiação Ionizante , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiaçãoRESUMO
In this paper, a distributed bearing-based formation control scheme with finite-time convergency is proposed for multiple underactuated surface vessels (USVs). By virtue of the guide point-based model transformation method, the dimension of underactuated tracking error dynamics can be reduced from three to two. This allows us to convert the actuator model to a fully form that matches dimension-reduced tracking error dynamics. Further, to reduce the computation complexity, a finite-time recruited filter is designed according to first-order Levant differentiator. At meanwhile, auxiliary error compensation signals are introduced to address unknowns stemming from filter process and system dynamics. Since merely relative-distances and inner bearings are utilized in the proposed bearing-based formation approaches, the proposed control scheme provides a feasible solution to achieve formation control under body-fixed frame. Finally, theoretical analysis and numerical simulations are presented to demonstrate the efficacy.
RESUMO
PURPOSE: This study aims to appraise the therapeutic effectiveness of intravitreal injections anti-vascular endothelial growth factor (anti-VEGF) vs alternative therapies in managing radiation retinopathy (RR). DESIGN: Systematic review and meta-analysis. METHODS: We obtained comprehensive data retrieval using PubMed, Embase, Web of Science, Scopus, and the Cochrane Library from their inception until December 15, 2023. This review included randomized controlled trials (RCTs) and nonrandomized studies (NRSs) reporting on best-corrected visual acuity (BCVA) among RR patients treated with intravitreal anti-VEGF. Study selection and data extraction were meticulously performed by 2 independent reviewers. The Cochrane Risk of Bias Tool 2.0 (RoB 2.0) and Risk of Bias in Nonrandomized Studies of Interventions (ROBINS-I) scales were utilized for bias risk assessment. Quantification of heterogeneity was executed using Q, H, and I2 statistics. The primary endpoint was the BCVA at the final observation point of each study. Secondary endpoints included central retinal thickness (CRT), foveal avascular zone (FAZ) area, and capillary density (CD) at the level of superficial capillary plexus. Subgroup analyses were undertaken to explore potential heterogeneity sources possibly due to treatment duration and study design. Sensitivity analyses were conducted to ascertain result stability. RESULTS: This analysis incorporated 7 studies (including 3 RCTs) encompassing 922 patients afflicted with RR. Relative to other treatment modalities, intravitreal anti-VEGF therapy was associated with a statistically significant mean decrease in BCVA of -0.34 logMAR (95% CI, -0.39 to -0.30 logMAR; I2 = 87.70%; P < .001), and a substantial reduction in CRT of -34.65 µm (95% CI, -50.70 to -18.60 µm; I2 = 30.40%; P < .001). Additionally, a reduction in the FAZ area by -0.69 mm² (95% CI, -0.91 to -0.46 mm², I2 = 0%; P < .001) was observed. A positive tendency was noted in CD at the superficial capillary plexus between anti-VEGF and other therapeutic interventions. CONCLUSIONS: Intravitreal anti-VEGF injections, in comparison to other treatments, demonstrate superior efficacy in enhancing BCVA and reducing CRT, thereby underscoring the potential of anti-VEGF in ameliorating radiation retinopathy outcomes. However, the conclusions are constrained by the incorporation of data from some NRSs and the small sample sizes.