Effects of shear stresses and antioxidant concentrations on the production of reactive oxygen species in lung cancer cells

Abstract

Reactive oxygen species (ROS) are known to be a key factor in the development of cancer, and many exogenous sources are supposed to be related to the formation of ROS. In this paper, a microfluidic chip was developed for studying the production of ROS in lung cancer cells under different chemical and physical stimuli. This chip has two unique features: (1) five relative concentrations of 0, 1/8, 1/2, 7/8, and 1 are achieved in the culture regions; (2) a shear stress gradient is produced inside each of the five culture areas. Lung cancer cells were seeded inside this biocompatible chip for investigating their response to different concentrations of H 2 O 2 , a chemical stimulus known to increase the production of ROS. Then the effect of shear stress, a physical stimulus, on lung cancer cells was examined, showing that the production of ROS was increased in response to a larger shear stress. Finally, two antioxidants, a-tocopherol and ferulic acid, were used to study their effects on reducing ROS. It was found that high-dose a-tocopherol was not able to effectively eliminate the ROS produced inside cells. This counter effect was not observed in cells cultured in a traditional chamber slide, where no shear stress was present. This result suggests that the current microfluidic chip provides an in vitro platform best mimicking the physiological condition where cells are under circulating conditions. V C 2013 AIP Publishing LLC. [http://dx

Hypoxia and free radicals: Role in tumor progression and the use of engineering-based platforms to address these relationships

“…Regarding ROS expression from tumor cells, Bischel et al [106] co-cultured prostate cancer cells with bone marrow stromal cells in a microfluidic device and discovered that the bone marrow stromal cells facilitated invasive prostate cancer cell behaviors as a result of increased tumoral ROS expression. Lo et al [107] seeded lung cancer cells in a microfluidic device and examined ROS expression in response to shear stress, reporting that high levels of shear stress resulted in proportionately higher levels of cellular ROS expression.…”

Design and Fabrication of a Microfluidic Viscometer Based on Electrofluidic Circuits

“…The third layer had two symmetric parts serving for sample pretreatment (see the green part in Figure 1 b), with each part consisting of two inlets and a continuous zigzag microchannel for mixing and diluting liquid samples. This zigzag structure is very commonly used in microfluidics for mixing and diluting purposes [ 27 , 28 , 29 , 30 , 31 , 32 ]. Compared to a straight microchannel, the total length of mixing is significantly increased in a zigzag microchannel.…”

“…Firstly, the sample-pretreatment layer can be used to mix and/or dilute liquid samples. By redesigning this device to have multiple samples of different concentrations [ 27 , 28 , 29 ], with each corresponding to one electrofluidic sensing region, it can serve as a platform for measurements of fluidic viscosity in a fast, accurate, and high-throughput manner. Secondly, cells can be cultured inside this microfluidic chip for monitoring their responses to fluidic shear stress and viscosity.…”

Morphological plasticity of bacteria—Open questions

“…6(b)) and establish the gradients of temperature 46 ( Fig. 7(a)), reactive oxidative species, 47 or pH 48 ( Fig. 7(b)) have been demonstrated to investigate cellular responses to parametric changes in these environmental factors.…”

“…10). First, ascribing to microfluidic devices enabling graded control of respective environmental cues [45][46][47][48] (Figs. 6(b), 7(a), and 7(b)), integration of multi-level, multi-factor controls in the system could elicit combinations of system inputs in FSC strategy, which is aimed to search optimized combinations of environmental cues that support long-term maintenance of specific morphological variants (goal 1 in Fig.…”