Carvacrol, a major monoterpenoid phenol from Origanum and Thymus species, has been shown to exhibit antiproliferative and anticancer properties in a few recent studies. Nevertheless, detailed mechanism of the action of this compound in prostate cancer has not been elucidated yet. Therefore, in the current study, we examined the anticancer activity and mechanism of the action of carvacrol against human prostate cancer cells. It was found that the treatment of DU145 cells with carvacrol decreased cell viability in a concentration and time-dependent manner. The antiproliferative action of carvacrol leads to induction of apoptosis as confirmed by nuclear condensation, Annexin V-FITC/PI positive cells, and caspase-3 activation. In addition, carvacrol augmented reactive oxygen species generation and disruption in the mitochondrial membrane potential which has not been reported in the previous studies of carvacrol with prostate cancer. Moreover, carvacrol-induced apoptosis of prostate cancer cells was also accompanied by significant amount of growth arrest at the G0/G1 phase of the cell cycle which has also not been documented previously. To sum up, this study has established that carvacrol could be a promising chemotherapeutic agent and could have a direct practical implication and translational relevance to prostate cancer patients as Origanum consumption may retard prostate cancer progression.

Andrographolide, a diterpenoid lactone and a major constituent of Andrographis paniculata Nees, exhibits remarkable anticancer activity. However, the effect of andrographolide on colon cancer has not been completely elucidated yet. Thus, we investigated the chemopreventive potential of andrographolide in colon cancer HT-29 cells. The cytotoxic potential of andrographolide on HT-29 cells was determined by MTT assay, trypan blue exclusion assay, colony formation assay, and morphological analysis; and apoptotic property by DAPI and Hoechst staining, FITC-Annexin V assay, DNA fragmentation assay and caspase-3 activity assay. To elucidate andrographolide action, intracellular reactive oxygen species (ROS) level was determined by DCFDA dye; change in mitochondrial potential by Rhodamine123 and Mito Tracker Red CMXRos dye; and cell cycle modulatory property by flow cytometric analysis. Results of the study have shown that andrographolide decreased cell viability of HT-29 cells in a dose- and time-dependent manner. Furthermore, andrographolide induced apoptosis in HT-29 cells which seemed to be linked with augmented intracellular ROS level and disruption of mitochondrial membrane potential. Interestingly, andrographolide caused significant cell cycle arrest in G2/M phase at lower doses, but, in G0/G1 phase at higher doses. In summary, our results indicated that andrographolide exhibited antiproliferative and apoptotic properties against colon cancer HT-29 cells.

Cervical cancer is the fourth most common cancer among women worldwide and is a major cause of morbidity and mortality. High-risk Human Papilloma Virus (mostly type 16 & 18) infection is the primary risk factor for the development of cervical carcinoma. The quest for strong, safe and cost effective natural antiproliferative agents that could reduce cervical cancer have been focussed now a day. Recently, glycyrrhizin, a triterpene glycoside (saponin) from licorice (Glycyrrhiza glabra Linn.), has been shown to exhibit potent antiproliferative and anticancer properties in a few preliminary studies. However, potential of this compound in cervical cancer has not been elucidated yet. Therefore the objective of this study was to analyze the antiproliferative and apoptotic properties of glycyrrhizin in human cervical cancer HeLa cells. Our results showed that glycyrrhizin exposure significantly reduced the cell viability of HeLa cells with a concomitant increase in nuclear condensation and DNA fragmentation in a dose dependent manner. The intracellular ROS generation assay showed dose-related increment in ROS production induced by glycyrrhizin. Glycyrrhizin also induced apoptosis in cervical cancer cells by exerting mitochondrial depolarization. Cell cycle study showed that glycyrrhizin induced cell cycle arrest in G₀/G1 phase of cell cycle in a dose dependent manner. Thus, this study confirms the efficacy of glycyrrhizin in cervical cancer cells which could be an adjunct in the better prevention and management of cervical cancer worldwide.

Autophagy is a process essential for cellular energy consumption, survival, and defense mechanisms. The role of autophagy in several types of human cancers has been explicitly explained; however, the underlying molecular mechanism of autophagy in glioblastoma remains ambiguous. Autophagy is thought to be a “double-edged sword”, and its effect on tumorigenesis varies with cell type. On the other hand, autophagy may play a significant role in the resistance mechanisms against various therapies. Therefore, it is of the utmost importance to gain insight into the molecular mechanisms deriving the autophagy-mediated therapeutic resistance and designing improved treatment strategies for glioblastoma. In this review, we discuss autophagy mechanisms, specifically its pro-survival and growth-suppressing mechanisms in glioblastomas. In addition, we try to shed some light on the autophagy-mediated activation of the cellular mechanisms supporting radioresistance and chemoresistance in glioblastoma. This review also highlights autophagy’s involvement in glioma stem cell behavior, underlining its role as a potential molecular target for therapeutic interventions.