Indole curcumin combats metastatic HBV-positive hepatocellular carcinoma by inhibiting cell proliferation, migration, and matrix metalloproteinase-9 activity

Cytotoxic potential of an indole-conjugated Oleanolic acid analogue: suppression of NSCLC proliferation through modulation of mitochondrial apoptotic dynamics

Pre-clinical toxicological investigations are pivotal in the development of safer and more efficacious chemotherapeutic agents. Oleanolic acid (OA), a naturally occurring pentacyclic triterpenoid, has demonstrated anticancer potential but is often limited by the toxic side effects of its derivatives. In the current study, we carried out the facile synthesis of a modified OA analogue, OD2, and studied its cytotoxicity and efficacy analysis across several cell lines. Mechanistic toxicology was explored through fluorescence-based assays. Annexin-V/Propidium Iodide (A-V/PI) staining and TUNEL assays were used to confirm apoptosis. OD2 exhibited dose-dependent cytotoxicity, with a pronounced effect on A549 lung cancer cells compared to other cancerous and non-cancerous cell lines. Apoptosis was found to be the predominant mode of cell death, evidenced by Fluorescence imaging analysis of chromatin condensation and mitochondrial dysfunction. This was further validated by an increase in Annexin-V-positive and TUNEL-positive cells in treated groups. OD2 activated the intrinsic mitochondrial apoptotic pathway as evidenced by increased Bax and decreased Bcl-2 protein abundance levels. While the current study showcases the therapeutic potential of the selective toxicological activity of OD2, future studies will focus on the deconvolution of its potential polypharmacological mode of action and decoding the basis of its selective action, so as to glean important lessons that can be applied in the development of chemotherapeutic agents with favorable toxicological profiles.

An in-vitro study of active targeting & anti-cancer effect of folic acid conjugated chitosan encapsulated indole curcumin analogue nanoparticles

Natural compounds like Curcumin with anti-cancer, anti-inflammatory and anti-bacterial properties are good target for drug development but its poor aqueous solubility, bioavailability, and low retention properties makes it a poor drug candidate in clinical settings. Here in this study, we have used an indole curcumin analogue (ICA) that has better bioavailability and enhanced permeability and retention (EPR) effect than curcumin. To make an active targeting drug we have designed folic acid conjugated chitosan-based nanoparticles encapsulating Indole curcumin analogue (CS-FA-ICA-np). The physical characteristics of CS-FA-ICA-np were evaluated by DLS, SEM, FTIR, XPS, XRD and TGA. Anti-cancer activity was analyzed using MTT, Fluorescence staining, Flow cytometry, comet assay, DNA fragmentation assay, wound healing, gelatin zymography, chick chorioallantoic membrane (CAM) assay and hemolysis assay. The size of CS-FA-ICA-nps were found to be 111 nm, and spherical in shape as observed in SEM. In-vitro assays show that CS-FA-ICA np has IC50 of 90 μg/mL in MDA-MB-231, increases ROS concentration, arrests cell cycle in G2-M phase, reduces matrix metalloproteinase-9 (MMP-9) activity and initiates apoptosis in cancer cells. Our results indicate that encapsulation of ICA increases its anti-cancer effect, drug stability, enhanced drug delivery to cancer microenvironment.

Downregulation of MMP-9 by epicatechin can improve the radiosensitivity of non-small cell lung cancer

BACKGROUND AND PURPOSE

Radiation therapy is a crucial treatment for nonsmall cell lung cancer (NSCLC), but its effectiveness is limited by the resistance of tumor cells to radiation. This study aimed to evaluate the effect of epicatechin (EC) on radiosensitivity in NSCLC and to determine its relationships with matrix metalloproteinase (MMP)-9.

METHODS

MMP-9 expression was detected by Western blotting, and the expression of the DNA damage marker protein was detected by immunofluorescence. Cell viability was assessed using the CCK-8 assay, and cell proliferation was evaluated using the clonogenesis assay. Flow cytometry was used to determine the cell apoptosis, whereas cell migration and invasion were detected using the transwell assays. The cells were treated with ionizing radiation (IR) and EC to verify the sensitizing effect of EC on radiation therapy.

RESULTS

MMP-9 expression was elevated in the NSCLC cells and tissues. DNA damage and cell apoptosis were increased, whereas cell vigor, proliferation, migration, and invasion were significantly decreased after IR. MMP-9 knockdown strengthened the impact of IR on the biological behaviors of the cells. EC + IR had the best effect on promoting DNA damage and the biological behaviors of the NSCLC cells; alternatively, the overexpression of MMP-9 weakened the role of EC.

CONCLUSIONS

This study shows that EC can downregulate MMP-9 expression, promote DNA damage, reduce cell viability, proliferation, migration, and invasion, and facilitate cell apoptosis, thus, showing potential as a radiosensitizer for NSCLC.

Research status of indole-modified natural products

Indole is a heterocyclic compound formed by the fusion of a benzene ring and pyrrole ring, which has rich biological activity. Many indole-containing compounds have been sold on the market due to their excellent pharmacological activity. For example, vincristine and reserpine have been widely used in clinical practice. The diverse structures and biological activities of natural products provide abundant resources for the development of new drugs. Therefore, this review classifies natural products by structure, and summarizes the research progress of indole-containing natural product derivatives, their biological activities, structure-activity relationship and research mechanism which has been studied in the past 13 years, so as to provide a basis for the development of new drug development.