Surgical excision promotes tumor growth and metastasis by promoting expression of MMP-9 and VEGF in a breast cancer model

Surgery is still the main curative therapeutic modality for breast cancer. Although surgery often results in the successful removal of the primary tumor, its process could increase the risk of metastases of residual cancer cells. Understanding of the connection between breast cancer metastasis and surgical wound will lead to the establishment of a proper treatment strategy for postoperative cancer patient. Aim: To study the influence of surgical procedure on the metastasis of primary breast cancer. Methods: We established MDA-MB-435 human breast cancer xenograft model. Levels of Pro-matrix metalloproteinase 9 (Pro-MMP-9) and vascular endothelial growth factor (VEGF) in host serum and tumors were tested at different time points with ELISA and zymography and correlated to tumor growth and postoperative metastasis. Results: Our study demonstrated surgical wound had promoting effect on tumor growth and pulmonary metastasis of human breast cells, if tumor cells remain in bodies. This effect might be related to the postoperative interaction of cancer and host cells, which resulted in expression of Pro-MMP-9. Surgical process could also increase the VEGF expression in tumor tissues. Conclusions: Surgical wound-produced host Pro-MMP-9 and tumor cell VEGF might be important mediators leading to metastasis of residual breast cancer after surgery.Хирургическое лечение до сих пор остается главным терапевтическим подходом при лечении больных раком молочной железы. Хотя хирургическое удаление опухоли в большинстве случаев достаточно эффективно, в то же время оно может увеличить риск метастазирования остаточных опухолевых клеток. Понимание связи между метастазированием при раке молочной железы и операционной раной позволит выбрать наилучшую стратегию постоперационного лечения. Цель: определить влияние хирургического вмешательства на метастазирование опухоли. Методы: была создана модель рака молочной железы человека в виде ксенотрансплантата MDA-MB-435. Уровень Pro-матричной металлопротеиназы 9 (Pro-MMP-9) и фактора роста эндотелия сосудов (VEGF) в сыворотке реципиента и опухолях оценивались в разные временные промежутки методом ELISA и зимографии. При этом определяли наличие корелляции между этими показа- и зимографии. При этом определяли наличие корелляции между этими показа и зимографии. При этом определяли наличие корелляции между этими показателями, ростом опухоли и постоперационными метастазами. Результаты: было показано, что операционная рана способствует росту опухоли молочной железы и ее метастазированию в легкие в случае, когда при удалении опухоли в ране остаются опухолевые клетки. Это может быть связано с постоперационным взаимодействием опухолевых и окружающих их нормальных клеток, которое приводит к экспрессии Pro-MMP-9. Удаление опухоли может также способствовать увеличению экспрессии VEGF опухолевыми клетками. Выводы: Pro-MMP-9, экспрессируемый нормальными клетками, окружающими постоперационную рану, а также VEGF, продуцируемый опухолевыми клетками, могут быть важными медиаторами метастазирования остаточных опухолевых клеток после хирургического вмешательства

Measurement of the Atmospheric Muon Spectrum from 20 to 3000 GeV

The absolute muon flux between 20 GeV and 3000 GeV is measured with the L3 magnetic muon spectrometer for zenith angles ranging from 0 degree to 58 degree. Due to the large exposure of about 150 m2 sr d, and the excellent momentum resolution of the L3 muon chambers, a precision of 2.3 % at 150 GeV in the vertical direction is achieved. The ratio of positive to negative muons is studied between 20 GeV and 500 GeV, and the average vertical muon charge ratio is found to be 1.285 +- 0.003 (stat.) +- 0.019 (syst.).Comment: Total 32 pages, 9Figure

Generalized Second Law of Thermodynamics in f(T)f(T) Gravity with Entropy Corrections

We study the generalized second law (GSL) of thermodynamics in $f(T)$ cosmology. We consider the universe as a closed bounded system filled with $n$ component fluids in the thermal equilibrium with the cosmological boundary. We use two different cosmic horizons: the future event horizon and the apparent horizon. We show the conditions under which the GSL will be valid in specific scenarios of the quintessence and the phantom energy dominated eras. Further we associate two different entropies with the cosmological horizons: with a logarithmic correction term and a power-law correction term. We also find the conditions for the GSL to be satisfied or violated by imposing constraints on model parameters.Comment: 17 pages, no figure, title changed, version accepted for publication in Astrophysics and Space Scienc

Unveiling the ultrafast optoelectronic properties of 3D Dirac semi-metal Cd3As2

We employ ultrafast optical-pump terahertz-probe spectroscopy and ultrafast THz emission spectroscopy to investigate the ultrafast charge carrier dynamics in the 3D Dirac semi-metal CdAs. We extract the temperature-dependent electron mobility (16,000cmVs at 5K) for CdAs nanowire ensemble. We also demonstrate strong THz emission from both CdAs single crystal and nanowires, whose polarity depends strongly on incident angle and pump polarisation

Analysis of drug transporter expression in human intestinal Caco-2 cells by real-time PCR.

International audienceExpression of drug transporters corresponds to a crucial parameter in intestinal Caco-2 cells widely used for investigating drug absorption. In order to characterize it in an accurate, reproducible and comparative manner, we analyzed mRNA levels of 19 influx and efflux drug transporters through real-time quantitative polymerase chain reaction assays combined with the use of a total RNA reference standard. Profiles of transporter expression were found to be significantly correlated in two independent Caco-2 cell clones and in human small intestine, which may support the use of Caco-2 cells for investigating intestinal drug transport. Several transporters were nevertheless quantitatively expressed at higher (MRP2, MRP3, MRP4, MRP5, MRP6, OATP-A, OATP-B, OCT1 and MCT1) or lower (BCRP) levels in Caco-2 cells comparatively to small intestine. Moreover, MDR1, MRP2, OATP-A and PEPT1 mRNA relative expression were found to differ in the two analyzed Caco-2 cell clones by at least a twofold factor, highlighting that some variations in transporter expression may occur in Caco-2 cells depending on cell origin, and therefore underlining the interest of carefully characterizing transporter levels in any Caco-2 cell clone before its use for drug transport assays