In-vitro Chemopreventive Potential of a Chromone from Bomarea setacea (ALSTROEMERIACEAE) against Colorectal Cancer

Dodonaea viscosa Jacq. induces cytotoxicity, antiproliferative activity, and cell death in colorectal cancer cells via regulation of caspase 3 and p53

Colorectal cancer (CRC) is the third most common cancer diagnosed worldwide and is the second leading cause of cancer-related death due to an insufficiency prognosis and is generally diagnosed in the last step of development. The Peruvian flora has a wide variety of medicinal plants with therapeutic potential in several diseases. Dodonaea viscosa Jacq. is a plant used to treat inflammatory process as well as gastrointestinal diseases. The aim of this study was to examine the cytotoxic, antiproliferative, and cell death-inducing effects of D. viscosa on colorectal cancer cells (SW480 and SW620). The hydroethanolic extract was obtained by maceration at 70% ethanol, the phytochemical constituents were identified by LC-ESI-MS. D. viscosa revealed 57 compounds some of them are: isorhamnetin, kaempferol, quercetin, methyl dodovisate B, hardwickiic acid, viscosol, and dodonic acid. Regarding the antitumoral activity, D. viscosa induced cytotoxic and antiproliferative activity in both SW480 and SW620 cancer cells, accompanied with, important changes in mitochondrial membrane potential, formation of the Sub G0/G1 population and increasing levels of apoptotic biomarkers (caspase 3 and the tumor suppressor protein p53) in the metastatic derivative cell line (SW620), suggesting an intrinsic apoptotic process after the treatment with the hydroethanolic extract of D. viscosa.

Froriepia subpinnata Leaf Extract-Induced Apoptosis in the MCF-7 Breast Cancer Cell Line by Increasing Intracellular Oxidative Stress

Background

Froriepia subpinnata is one of the plants used in the diet of Iranian people. Previous studies have investigated the antioxidant and antibacterial effects of this plant extract, but no study has been conducted on its anticancer properties.

Objectives

In this study, we investigated the effect of F. subpinnata extract on MCF-7 breast cancer cells.

Methods

The inhibitory effect of F. subpinnata leaf extract was determined on the growth of cancer cells by the MTT test. The ROS (reactive oxygen species) test was used to investigate the impact of the extract on intracellular oxidative stress. Flow cytometry and real-time PCR tests were used to investigate the apoptosis-related molecular processes. The GC-MS analysis was performed to determine the most abundant components.

Results

The GC-MS analysis showed that phytol, mono-ethylhexyl phthalate (MEHP), cinnamaldehyde, and neophytadiene constituted 60% of the extracted content. The MTT assay demonstrated that F. subpinnata leaf extract caused 50% lethality at a 400 μg/mL dose in MCF7 cells. The F. subpinnata extract at low doses decreased the ROS level for 24 hours in MCF-7, but by increasing the concentration, the ROS levels increased. At the IC50 dose (inhibitory concentration (IC) associated with 50% impact), the ROS level increased 3.5 times compared to the control group. Examining the effect of N-acetyl cysteine (NAC) showed that this antioxidant agent could prevent the lethal impact of the extract and eliminate the ROS increase in MCF7 cells. Flow cytometry and real-time PCR results showed that the extract specifically induced apoptosis through the internal apoptosis pathway in this cancer cell line.

Conclusions

The F. subpinnata extract induced apoptosis by increasing ROS in MCF-7 cancer cells and can be considered for further studies.

Synthesis and Chemopreventive Potential of 5-FU/Genistein Hybrids on Colorectal Cancer Cells

A series of 5-FU-Genistein hybrids were synthesized and their structures were elucidated by spectroscopic analysis. The chemopreventive potential of these compounds was evaluated in human colon adenocarcinoma cells (SW480 and SW620) and non-malignant cell lines (HaCaT and CHO-K1). Hybrid 4a displayed cytotoxicity against SW480 and SW620 cells with IC₅₀ values of 62.73 ± 7.26 µM and 50.58 ± 1.33 µM, respectively; compound 4g induced cytotoxicity in SW620 cells with an IC₅₀ value of 36.84 ± 0.71 µM. These compounds were even more selective than genistein alone, the reference drug (5-FU) and the equimolar mixture of genistein plus 5-FU. In addition, hybrids 4a and 4g induced time- and concentration-dependent antiproliferative activity and cell cycle arrest at the S-phase and G2/M. It was also observed that hybrid 4a induced apoptosis in SW620 cells probably triggered by the extrinsic pathway in response to the activation of p53, as evidenced by the increase in the levels of caspases 3/8 and the tumor suppressor protein (Tp53). Molecular docking studies suggest that the most active compound 4a would bind efficiently to proapoptotic human caspases 3/8 and human Tp53, which in turn could provide valuable information on the biochemical mechanism for the in vitro cytotoxic response of this compound in SW620 colon carcinoma cell lines. On the other hand, molecular dynamics (MD) studies provided strong evidence of the conformational stability of the complex between caspase-3 and hybrid 4a obtained throughout 100 ns all-atom MD simulation. Molecular mechanics Poisson-Boltzmann surface area (MM-PBSA) analyses of the complex with caspase-3 showed that the interaction between the ligand and the target protein is stable. Altogether, the results suggest that the active hybrids, mainly compound 4a, might act by modulating caspase-3 activity in a colorectal cancer model, making it a privileged scaffold that could be used in future investigations.