Hormonal-receptor positive (HRP) breast cancer patients with positive metastatic axillary lymph nodes are characterized by poor prognosis and increased mortality rate. The mechanisms by which cancer cells invade lymph nodes have not yet been fully explored. Several studies have shown that expression of IL-6 and the proteolytic enzyme cathepsin B (CTSB) was associated with breast cancer poor prognosis. In the present study, the effect of different concentrations of recombinant human IL-6 on the invasiveness capacity of HRP breast cancer cell line MCF-7 was tested using an in vitro invasion chamber assay. The impact of IL-6 on expression and activity of CTSB was also investigated. IL-6 treatment promoted the invasiveness potential of MCF-7 cells in a dose-dependent manner. Furthermore, MCF-7 cells displayed elevated CTSB expression and activity associated with loss of E-cadherin and upregulation of vimentin protein levels upon IL-6 stimulation. To validate these results in vivo, the level of expression of IL-6 and CTSB in the carcinoma tissues of HRP-breast cancer patients with positive and negative axillary metastatic lymph nodes (pLNs and nLNs) was assessed. Western blot and immunohistochemical staining data showed that expression of IL-6 and CTSB was higher in carcinoma tissues in HRP-breast cancer with pLNs than those with nLNs patients. ELISA results showed carcinoma tissues of HRP-breast cancer with pLNs exhibited significantly elevated IL-6 protein levels by approximately 2.8-fold compared with those with nLNs patients (P < 0.05). Interestingly, a significantly positive correlation between IL-6 and CTSB expression was detected in clinical samples of HRP-breast cancer patients with pLNs (r = 0.78, P < 0.01). Collectively, this study suggests that IL-6-induced CTSB may play a role in lymph node metastasis, and that may possess future therapeutic implications for HRP-breast cancer patients with pLNs. Further studies are necessary to fully identify IL-6/CTSB axis in different molecular subtypes of breast cancer.

Cancer is still one of the deadly diseases worldwide and the need for naturally-derived effectors is a pursued aim in health research. With the outstanding ability to bypass the host’s various defense mechanisms, tick saliva constitutes an interesting rich source for the discovery of therapeutically-valuable molecules. Therefore, the present work aimed to evaluate the anti-tumor potential of Hyalomma dromedarii salivary glands extract (SGE). Three cell lines were used in this study, namely HCT116 (colorectal cancer), A549 (lung cancer) and HFB4 (normal skin) cells. MTT assay and light microscopy revealed significant dose-dependent inhibition of proliferation with obvious morphological changes in tested cell lines. Colon cells exhibited more sensitivity than lung ones, therefore they were selected for further investigations. Although cytotoxic effects were observed in treated-HFB4 cells, its IC50 value was much higher than that of HCT116 cells. Flow cytometry analysis of treated HCT116 cells showed accumulation of cellular DNA at the G2/M phase and induction of apoptosis. In addition, RT-qPCR indicated down-regulation in the expression of vascular endothelial growth factor (VEGF), fibroblast growth factor-2 (FGF-2), transforming growth factor-β (TGF-β) and interleukin-4 (IL-4) genes. These results demonstrated that H. dromedarii SGE has anti-proliferative, apoptotic and anti-angiogenic potential. Also, they open perspectives for characterization of effective molecules that could be used in developing treatments for colorectal cancer. Further investigations are required to identify the mechanisms, molecules and signaling pathways involved in the inhibitory effect of the SGE.

This article extensively investigates the calculations of the compensation factor of the thyristor-controlled series compensator (TCSC), which are used to accurately evaluate the negative impacts of the TCSC on the performance of conventional distance relays. To broadly evaluate the distance protection performance, the TCSC was adapted to the IEEE 9-bus system as one of the interconnected transmission networks that are increasingly spreading to improve service reliability, reduce reserve capacity, and enhance system efciency. In addition, IEEE 39-bus system, as a large interconnected system, is also examined to generalize the TCSC impact on different interconnected systems. To determine the precise impact, the impedance of the TCSC was calculated based on its practical design parameters. The impedance of the TCSC was examined as a function of transmission line impedance and ring angle. Both Mho and Quadrilateral distance relays were tested using the MATLAB/Simulink environment for different types of faults, fault locations, fault resistances, and ring angles for capacitive, inductive, and blocking modes of TCSC operation. In addition, distance relay performance was evaluated during power swing phenomenon in the presence of the TCSC. Simulation tests indicated the negative impacts of the TCSC on distance relay operation, which are not limited to over-reach and under-reach in faulty conditions but also to maloperation in dynamic disturbances that cause power swing phenomena on the protected line.