The Chromone Alkaloid, Rohitukine, Affords Anti-Cancer Activity via Modulating Apoptosis Pathways in A549 Cell Line and Yeast Mitogen Activated Protein Kinase (MAPK) Pathway

Abstract

The field of cancer research and treatment has made significant progress, yet we are far from having completely safe, efficient and specific therapies that target cancer cells and spare the healthy tissues. Natural compounds may reduce the problems related to cancer treatment. Currently, many plant products are being used to treat cancer. In this study, Rohitukine, a natural occurring chromone alkaloid extracted from Dysoxylum binectariferum, was investigated for cytotoxic properties against budding yeast as well as against lung cancer (A549) cells. We endeavored to specifically study Rohitukine in S. cerevisiae in the context of MAPK pathways as yeast probably represents the experimental model where the organization and regulation of MAPK pathways are best understood. MAPK are evolutionarily conserved protein kinases that transfer extracellular signals to the machinery controlling essential cellular processes like growth, migration, differentiation, cell division and apoptosis. We aimed at carrying out hypothesis driven studies towards targeting the important network of cellular communication, a critical process that gets awry in cancer. Employing mutant strains of genetic model system Saccharomyces cerevisiae. S. cerevisiae encodes five MAPKs involved in control of distinct cellular responses such as growth, differentiation, migration and apoptosis. Our study involves gene knockouts of Slt2 and Hog1 which are functional homologs of human ERK5 and mammalian p38 MAPK, respectively. We performed cytotoxicity assay to evaluate the effect of Rohitukine on cell viability and also determined the effects of drug on generation of reactive oxygen species, induction of apoptosis and expression of Slt2 and Hog1 gene at mRNA level in the presence of drug. The results of this study show a differential effect in the activity of drug between the WT, Slt2 and Hog1 gene deletion strain indicating involvement of MAPK pathway. Further, we investigated Rohitukine induced cytotoxic effects in lung cancer cells and stimulated the productions of ROS after exposure for 24 hrs. Results from western blotting suggest that Rohitukine triggered apoptosis in A549 cell line through upregulation of p53, caspase9 and down regulation of Bcl-2 protein. The scope of this study is to understand the mechanism of anticancer activity of Rohitukine to increase the repertoire of anticancer drugs, so that problem created by emergence of resistance towards standard anticancer compounds can be alleviated.

SPARCL1 suppresses cell migration and invasion in renal cell carcinoma

“…MAPK pathways are crucial in regulating cell differentiation (24)(25)(26), proliferation (27)(28)(29)(30) and survival (31)(32)(33). Mutations of the MAPK pathway proteins have been reported to be associated with several types of human cancer (34)(35)(36)(37)(38).…”

Fungal Endophytes as Efficient Sources of Plant-Derived Bioactive Compounds and Their Prospective Applications in Natural Product Drug Discovery: Insights, Avenues, and Challenges

“…However, the removal of bark poses a threat to the survival of the source medicinal plant. Rohitukine exhibits anticancer activity through the up-regulation of p53 and caspase-9 and down-regulation of Bcl-2 protein [ 95 ]. In 2012, Kumara and his group isolated an endophyte Fusarium proliferatum from D. binectariferum that produces host-derived rohitukine [ 66 ].…”

Emerging Cytotoxic Alkaloids in the Battle against Cancer: Overview of Molecular Mechanisms

“…Similarly, rohitukine (isolated from Dysoxylum binectariferum Hook.f. ), had significant cytotoxicity against breast cancer, ovarian cancer, and lung cancer via ROS generation [ 41 ]. Topotecan, a commonly used chemotherapeutic agent and topoisomerase inhibitor, acts against many cancers, mainly cervical cancer and small cell lung cancer, by creating double-stranded DNA damage [ 56 ].…”

“…Therefore, many anticancer drugs have been designed to modify and complement these disruptions. Two emerging alkaloids, rohitukine and hirsutine ( Figure 1 ), activate p38 MAPKs leading to a dose-dependent cytotoxicity against breast cancer, ovarian, and lung cancer [ 41 , 43 ]. On the other hand, β-carboline alkaloid ( Figure 3 ), isolated from Peganum harmala L., was found to exert its anticancer potential against human promyelocytic leukemia, prostate cancer, and gastric cancer by increasing the levels of Phosphatase and Tensin Homolog (PTEN) and decreasing the levels of ERK [ 45 ].…”