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Oral lichen planus (OLP) is a particularly prevalent oral disorder with the potential to progress to oral squamous cell carcinoma (OSCC). SRY‐box transcription factor 11 (Sox11) has been reported to serve as a prognostic marker for various cancers. However, the role and mechanism of Sox11 in OLP‐related OSCC are unknown. Our results indicated that Sox11 was highly expressed, and that Sox11 promoter methylation was significantly reduced in OLP‐associated OSCC tissues. High Sox11 expression and Sox11 promoter hypomethylation indicate a poor patient prognosis. According to in vivo and in vitro experiments, the knockdown of Sox11 inhibited proliferation, invasion, and migration while driving its apoptotic death in OSSC cells; Sox11 overexpression exerted the opposite effect as Sox11 knockdown. Mechanistically, knockdown of Sox11 inhibited PI3K/AKT and glycolysis pathway, and overexpression of Sox11 enhanced the PI3K/AKT and glycolysis pathways in OSCC cells. In addition, we demonstrated that Sox11 overexpression accelerated the progression of OSCC, at least in part by promoting PI3K/AKT pathway activation. In conclusion, our data indicated that the DNA hypomethylation‐associated upregulation of Sox11 could promote oncogenic transformation via the PI3K/AKT pathway in OLP‐associated OSCC. Therefore, Sox11 might be a reliable biomarker for predicting the progression of precancerous oral tissues. [ABSTRACT FROM AUTHOR]

Fractures and defects in wellbore cement can lead to increased possibilities of CO2 leakage from abandoned wells during geological carbon sequestration. To investigate the physicochemical response of defective wellbore cement to CO2-rich brine, we carried out a reactive flow-through experiment using an artificially fractured cement sample at a length of 224.8 mm. A brine solution with dissolved CO2 at a pH of approximately 3.9 was injected through the sample at a constant rate of 0.0083 cm3/s. Surface optical profilometry analysis and 3-D X-ray microtomography imaging confirmed fracture closure and self-healing behavior consistent with the measured permeability decrease. Visual inspection of the reacted fracture surface showed the development of reactive patterns mapping the flow velocity field inside the fracture, as well as restricted flow toward the sample outlet. The postexperiment permeability of the core sample was measured at half of its initial permeability. A reactive transport model was developed with parameters derived from the experiment to further examine property evolution of fractured cement under dynamic flow of CO2-rich brine. Sensitivity analysis showed that residence time and the size of initial fracture aperture are the key factors controlling the tendency to self-healing or fracture opening behavior and therefore determine the long-term integrity of the wellbore cement. Longer residence time and small apertures promote mineral precipitation, fracture closure, and therefore flow restriction. This work also suggests a narrow threshold separating the fracture opening and self-sealing behavior. [ABSTRACT FROM AUTHOR]

The interaction between wellbore cement and CO2 has the potential to alter cement properties and form preferential leakage pathways during geological carbon sequestration. This work investigates changes in wellbore cement integrity during continuous flooding of CO2-saturated brine. We created composite cement-sandstone core samples with a continuous gap in the cement zone in order to represent defects such as fractures and voids in wellbore cement. Volumetric and structural changes in the cement zone were monitored and quantified using X-ray Micro-Computed Tomography imaging. During an 8 day dynamic flow-through period, the fracture/void aperture increased significantly, whereas the host sandstone remained unaltered. The void volume increased at a faster rate in the early stage of the flow-through period than it did toward the end of the period. Compared to the apertures close to the core outlet, those located near the core inlet experienced more severe cement degradation, accompanied by a decrease in specific surface area, constituting evidence of a smoothing effect. Contrary to previous observations of the self-healing behavior of cement fractures, the in situ permeability on a parallel experiment increased by a factor of 8 after 10 days of flooding. Findings from this work will provide valuable insights applicable to the development of predictive models and for risk assessment under conditions relevant to CO2 sequestration. [ABSTRACT FROM AUTHOR]