Inhibition of the invasion and migration of renal carcinoma 786-o-si3 cells in vitro and in vivo by Koelreuteria formosana extract

Anticancer Activity of Rutin and Its Combination with Ionic Liquids on Renal Cells

The renal cell carcinoma (RCC) is the most common type of kidney cancer. Identifying novel and more effective therapies, while minimizing toxicity, continues to be fundamental in curtailing RCC. Rutin, a bioflavonoid widely found in nature, has shown promising anticancer properties, but with limited applicability due to its poor water solubility and pharmacokinetics. Thus, the potential anticancer effects of rutin toward a human renal cancer cell line (786-O), while considering its safety in Vero kidney cells, was assessed, as well as the applicability of ionic liquids (ILs) to improve drug delivery. Rutin (up to 50 µM) did not show relevant cytotoxic effects in Vero cells. However, in 786-O cells, a significant decrease in cell viability was already observed at 50 µM. Moreover, exposure to rutin caused a significant increase in the sub-G1 population of 786-O cells, reinforcing the possible anticancer activity of this biomolecule. Two choline-amino acid ILs, at non-toxic concentrations, enhanced rutin’s solubility/loading while allowing the maintenance of rutin’s anticancer effects. Globally, our findings suggest that rutin may have a beneficial impact against RCC and that its combination with ILs ensures that this poorly soluble drug is successfully incorporated into ILs–nanoparticles hybrid systems, allowing controlled drug delivery.

Thymoquinone suppresses the proliferation of renal cell carcinoma cells via reactive oxygen species-induced apoptosis and reduces cell stemness

Thymoquinone is a phytochemical compound isolated from Nigella sativa and has various biological effects, including anti-inflammation, antioxidation, and anticancer. Here, we further investigated the anticancer effects and associated molecular mechanism of 2-methyl-5-isopropyl-1,4-benzoquinone (thymoquinone) on human renal carcinoma cell lines 786-O and 786-O-SI3 and transitional carcinoma cell line BFTC-909. Results showed that thymoquinone significantly reduced cell viability, inhibited the colony formation of renal cancer cells, and induced cell apoptosis and mitochondrial membrane potential change in both cancer cells. In addition, thymoquinone also triggered the production of reactive oxygen species (ROS) and superoxide and the activation of apoptotic and autophagic cascade. ROS inhibition suppressed the caspase-3 activation and restored the decreased cell viability of 786-O-SI3 in response to thymoquinone. Autophagy inhibition did not restore the cell viability of 786-O-SI3 suppressed by thymoquinone. Moreover, thymoquinone suppressed the cell sphere formation and the expression of aldehyde dehydrogenase, Nanog, Nestin, CD44, and Oct-4 in 786-O-SI3 cells. The tumor-bearing model showed that thymoquinone in vivo inhibited the growth of implanted 786-O-SI3 cell. All these findings indicate that thymoquinone inhibits the proliferation of 786-O-SI3 and BFTC-909 cell possibly due to the induction of ROS/superoxide and the consequent apoptosis, suggesting that thymoquinone may be a potential anticancer supplement for genitourinary cancer.

Thymoquinone inhibits metastasis of renal cell carcinoma cell 786-O-SI3 associating with downregulation of MMP-2 and u-PA and suppression of PI3K/Src signaling

Phytochemicals represent an important source of novel anticancer and chemotherapeutic agents. Thymoquinone (TQ) is the major bioactive phytochemical derived from the seeds of Nigella sativa and has shown potent anticancer activities. In this study, we aimed to investigate the anticancer activity of Thymoquinone on the human renal carcinoma cell 786-O-SI3 and the underlying mechanism. By using cell proliferation assay, wound healing, and invasion assay, we found that Thymoquinone did not affect the viability of 786-O-SI3 and human kidney-2, but clearly inhibited the migration and invasion of 786-O-SI3. Further zymography and immunoblotting analysis showed that Thymoquinone downregulated the activity and expression of matrix metalloproteinase (MMP)-2 and urokinase-type plasminogen activator (u-PA) and attenuated the adhesion of 786-O-SI3 to type I and type IV collagen. Kinase cascade assay indicated that Thymoquinone inhibited the phosphorylation of phosphatidylinositol 3-kinase, Akt, Src, and Paxillin. In addition, Thymoquinone also decreased the level of fibronectin, N-cadherin, and Rho A. In parallel, Thymoquinone dose-dependently suppressed the transforming growth factor (TGF)-β-promoted u-PA activity and expression, as well as the cell motility and invasion of 786-O-SI3. Furthermore, tumor xenograft model revealed that Thymoquinone in vivo inhibited the 786-O-SI3 metastasizing to the lung. Collectively, these findings indicate that Thymoquinone inhibits the metastatic ability of 786-O-SI3, suggesting that Thymoquinone might be beneficial to promote the chemotherapy for renal cell carcinoma.

Bauhinia variegata candida Fraction Induces Tumor Cell Death by Activation of Caspase-3, RIP, and TNF-R1 and Inhibits Cell Migration and Invasion In Vitro

Metastasis remains the most common cause of death in cancer patients. Inhibition of metalloproteinases (MMPs) is an interesting approach to cancer therapy because of their role in the degradation of extracellular matrix (ECM), cell-cell, and cell-ECM interactions, modulating key events in cell migration and invasion. Herein, we show the cytotoxic and antimetastatic effects of the third fraction (FR3) from Bauhinia variegata candida (Bvc) stem on human cervical tumor cells (HeLa) and human peripheral blood mononuclear cells (PBMCs). FR3 inhibited MMP-2 and MMP-9 activity, indicated by zymogram. This fraction was cytotoxic to HeLa cells and noncytotoxic to PBMCs and decreased HeLa cell migration and invasion. FR3 is believed to stimulate extrinsic apoptosis together with necroptosis, assessed by western blotting. FR3 inhibited MMP-2 activity in the HeLa supernatant, differently from the control. The atomic mass spectrometry (ESI-MS) characterization suggested the presence of glucopyranosides, D-pinitol, fatty acids, and phenolic acid. These findings provide insight suggesting that FR3 contains components with potential tumor-selective cytotoxic action in addition to the action on the migration of tumor cells, which may be due to inhibition of MMPs.

In vitro polyphenol effects on apoptosis: An update of literature data

Polyphenols are secondary plant metabolites which have been studied extensively for their health-promoting properties, and which could also exert pharmacological activities ranging from anti-inflammatory effects, to cytotoxic activity against cancer cells. The main mechanism for programmed cell death is represented by apoptosis, and its dysregulation is involved in the etiopathology of cancer. As such, substances able to induce apoptosis in cancer cells could be used as new anticancer agents. The aim of this paper is to review literature data on the apoptotic effects of polyphenols and the molecular mechanisms through which they induce these effects in cancer cells. In addition, a brief summary of the new delivery forms used to increase the bioavailability, and clinical impact of polyphenols is provided. The studies reported show that many polyphenol rich plant extracts, originating from food and herbal medicine, as well as isolated polyphenols administered individually or in combination, can regulate cell apoptosis primarily through intrinsic and extrinsic mechanisms of action in in vitro conditions. Due to these promising results, the use of polyphenols in the treatment of cancer should therefore be deeply investigated. In particular, because of the low number of clinical trials, further studies are required to evaluate the anticancer activity of polyphenols in in vivo conditions.

Koelreuteria Formosana Extract Induces Growth Inhibition and Cell Death in Human Colon Carcinoma Cells via G2/M Arrest and LC3-II Activation-Dependent Autophagy

Autophagy is a self-destructive process that degrades cytoplasmic constituents. In our previous study, Koelreuteria formosana ethanolic extract (KFEE), which is obtained from natural plants endemic to Taiwan, has inhibited cell metastasis in renal carcinoma cells. However, the anticancer effects of KFEE on colon cancer remain unclear. In this study, KFEE exerted a strong cytotoxic effect on DLD-1 and COLO 205 human colorectal cancer cell lines. KFEE effectively inhibited cancer cell proliferation, induced G2/M-phase arrest associated with downregulaton of cyclin E, cyclin B and cdc25C and upregulation of p21, and induced cell death by activating autophagy but did not cause apoptotic cell death. Exposed KFEE cells showed increased levels of acridine orange, autophagic vacuoles, and LC3-II proteins, which are specific autophagic markers. Bcl-2, p-Akt, and p-mTOR levels, which have been implicated in autophagic downregulation, were decreased after KFEE treatment. Autophagy inhibitor 3-methyladenosine and bafilomycin-A1 and genetic silencing of LC3 attenuated KFEE-induced growth inhibition. These findings suggested that KFEE causes cytostatic effect through autophagy. In xenograft studies, oral administration of KFEE had significantly inhibited the tumor growth in nude mice that had received subcutaneous injection of DLD-1 cells. KFEE is a promising candidate in phytochemical-based, mechanistic, and pathway-targeted cancer prevention strategies.

The Topoisomerase 1 Inhibitor Austrobailignan-1 Isolated from Koelreuteria henryi Induces a G2/M-Phase Arrest and Cell Death Independently of p53 in Non-Small Cell Lung Cancer Cells

Koelreuteria henryi Dummer, an endemic plant of Taiwan, has been used as a folk medicine for the treatment of hepatitis, enteritis, cough, pharyngitis, allergy, hypertension, hyperlipidemia, and cancer. Austrobailignan-1, a natural lignan derivative isolated from Koelreuteria henryi Dummer, has anti-oxidative and anti-cancer properties. However, the effects of austrobailignan-1 on human cancer cells have not been studied yet. Here, we showed that austrobailignan-1 inhibited cell growth of human non-small cell lung cancer A549 and H1299 cell lines in both dose- and time-dependent manners, the IC₅₀ value (48 h) of austrobailignan-1 were 41 and 22 nM, respectively. Data from flow cytometric analysis indicated that treatment with austrobailignan-1 for 24 h retarded the cell cycle at the G2/M phase. The molecular event of austrobailignan-1-mediated G2/M phase arrest was associated with the increase of p21^Waf1/Cip1 and p27^Kip1 expression, and decrease of Cdc25C expression. Moreover, treatment with 100 nM austrobailignan-1 for 48 h resulted in a pronounced release of cytochrome c followed by the activation of caspase-2, -3, and -9, and consequently induced apoptosis. These events were accompanied by the increase of PUMA and Bax, and the decrease of Mcl-1 and Bcl-2. Furthermore, our study also showed that austrobailignan-1 was a topoisomerase 1 inhibitor, as evidenced by a relaxation assay and induction of a DNA damage response signaling pathway, including ATM, and Chk1, Chk2, γH2AX phosphorylated activation. Overall, our results suggest that austrobailignan-1 is a novel DNA damaging agent and displays a topoisomerase I inhibitory activity, causes DNA strand breaks, and consequently induces DNA damage response signaling for cell cycle G2/M arrest and apoptosis in a p53 independent manner.