الفهرس 
Introduction and aim of workOnly 14 pages are availabe for public view
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Abstract
Mammary carcinoma is the most prevalent malignancy worldwide (Katsura et al. 2022). Mammalian a high skill to easily spread to other organs in the body with easy recurrence. The high metastatic activity and recurrence rate make cancer more resistant to treatments and worsens prognosis and survival (Barzaman et al. 2020).
Pregnane glycosides (Russeliosides A-C) are the major natural compounds isolated from methanol extract of Caralluma tuberculata herb that belongs to the subfamily Asclepiadaceae and family Apocynaceae. Caralluma tuberculata and other members of Asclepiadaceae family are known as a rich natural source of pregnane glycosides, which are reported to have potential anti-tumour possessions contrary to different lines (Panda et al. 2006). Pregnane glycosides have structural similarities to estrogen agonists, therefore considered an attractive natural source for the detection of a new treatment for breast cancer (Waheed et al. 2011). In addition, the methanol and ethanol extracts of Caralluma tuberculata were reported to have an anti-proliferative effect against Cac-2 (Waheed et al. 2011). Furthermore, there are several reports regarding the anti-inflammatory effect of Russelioside B and its relationship with reducing blood levels of NF-B and IL-6, but no activity on tumor cells has been reported until now (El-Shiekh, El-Mekkawy, et al. 2021; El-Shiekh, Salama, et al. 2021).
This study aimed to study the effect of those pregnane glycosides on inflammatory mediated breast cancer in addition to detecting the possible mechanism of action by which they possess their activities.
Murine breast cancer cells (4T1-Luc2 and 4T1-NFB-Luc2) and human breast cancer cells (MDA-MB-231) were used. Cell proliferation was assessed using WST-8 kit at time points 24, 48 and 72 h. NF-B activity was measured on 4T1-NFB-Luc2 cells using a luciferase gene reporter assay. Western blot was used in evaluating the protein expression of NF-B (p65) and its phosphorylated form (P-p65). The metastatic feature was measured using a trans-well migration assay, trans-well invasion assay and wound healing assay. ELISA was used to estimate the level of the pro-inflammatory cytokine (IL-6). The expression of MMP-9 and VEGF-b were evaluated by quantitative real-time PCR. Finally, to test the anti-metastatic efficacy of the three drugs, researchers used a lung metastases paradigm in vivo.
Our study proposed that all three pregnane glycosides can inhibit breast cancer cell proliferation, invasion and migration in vitro, but only Russelioside A inhibits the in vivo breast cancer lung metastasis. The anti-tumor and anti-metastatic activities of the three Russeliosides A-C are found to be mediated through inhibition of the cell-intrinsic NF-B activity and the expression of its downstream target products, such as IL-6, MMP-9 and VEGF-b in TNBCs at different inhibitory points. The inhibitory effect of Russelioside A on triple-negative breast cancer metastasis is likely mediated through the blockade of NF-B (p65) phosphorylation activity but for the others through inhibition of NF-B binding activity to promotor sites. Therefore, we hereby demonstrated novel anti-cancer and anti-metastatic actions of Russeliosides A-C by inhibiting cell-intrinsic NF-B activity in breast cancer cells. Although additional extensive pre-clinical and although further clinical testing is necessary to determine their safety and efficacy in humans, Russeliosides A-C are promising phytochemicals for blocking the intrinsic propagation of oncogenes in cancer cells NF-B-dependent cancer-promoting inflammatory signals and a novel striking candidate for the treatment of breast cancer growth and metastasis.
In conclusion, our presented study demonstrated, for the first time, that methanol extract of Caralluma tuberculata herb and its extracted pregnane glycosides (Russelioside A, Russelioside B and Russelioside C) have potent and anti-inflammatory, actions against triple-negative breast cancer cell lines in mice and humans, inhibiting their ability to divide and spread in vitro. In addition, Russelioside A provides a potent anti-metastatic activity in vivo using the experimental lung metastasis model.