Chemotherapeutic effect of Zerumbone on melanoma cells through mitochondria-mediated pathways

Tumor-Inhibitory Effects of Zerumbone Against HT-29 Human Colorectal Cancer Cells

Colorectal cancer (CRC) is the second cause of cancer-associated death globally. Recently, herbal medicinal products and, in particular, zerumbone have been widely studied and used for cancer treatment as they induce significant anti-cancer effects. However, there is limited information about the anti-cancer effects of zerumbone in CRC. Therefore, we aimed to investigate the in vitro anti-cancer effects of the zerumbone in CRC, focusing on cell apoptosis and migration. Anti-proliferative and anti-migratory effects of zerumbone on HT-29 cells were evaluated using MTT and scratch wound healing assay, respectively. Quantitative real-time PCR (qRT-PCR) was performed to determine the mRNA expression levels of migration and apoptosis-related genes. Apoptosis and cell cycle distribution were evaluated by flow cytometry. The intracellular level of reactive oxygen species (ROS) was measured using a ROS assay kit. Additionally, matrix metalloproteinase-2/-9 (MMP-2/-9) activity was determined using gelatin zymography. Zerumbone suppressed the viability of the HT-29 cells dose-dependently while having less cytotoxicity on normal NIH/3T3 cells. Zerumbone induced apoptosis in HT-29 cells and arrested the cell cycle in the G2/M phase. These effects were associated with alteration in the expression of apoptosis-related genes (up-regulation of Bax and down-regulation of Bcl-2 genes). Zerumbone also enhanced the generation of ROS in HT-29 cells. Furthermore, zerumbone significantly inhibited the migration of HT-29 cells and decreased MMP-2/-9 mRNA expression and activity. Our findings provide a potential use for zerumbone to induce apoptosis and suppress metastasis in HT-29 cells; thus, it could be developed as a promising natural agent for future CRC therapy.

Bioactive Compounds from Zingiber montanum and Their Pharmacological Activities with Focus on Zerumbone

The genus Zingiber consists of about 85 species and many of these species are used as food, spices, and medicines. One of the species, Zingiber montanum (J. Koenig) Link ex A. Dietr. is native to Southeast Asia and has been extensively used as traditional medicines and food. The aim of this review was to collect and critically analyze the scientific information about the bioactive compounds and pharmacological activities of Z. montanum with focus on one of the main components, zerumbone (ZER). Various studies have reported the analysis of volatile constituents of the essential oils from Z. montanum. Similarly, many phenylbutanoids, flavonoids and terpenes were also isolated from rhizomes. These essential oils, extracts and compounds showed potent antimicrobial, anti-inflammatory and antioxidant activities among others. Zerumbone has been studied widely for its anticancer, anti-inflammatory, and other pharmacological activities. Future studies should focus on the exploration of various pharmacological activities of other compounds including phenylbutanoids and flavonoids. Bioassay guided isolation may result in the separation of other active components from the extracts. Z. montanum could be a promising source for the development of pharmaceutical products and functional foods.

Anti-Cancer and Anti-Angiogenesis Activities of Zerumbone Isolated from Zingiber Zerumbet - A Systematic Review

Significant number of literatures has demonstrated the antiproliferative effect of Zerumbone and its role as anti-angiogenesis. The aims of this systematic review were to assess the anti-cancer effects of Zerumbone and the role of its antiangiogenic properties in treating cancer. Relevant articles were selected based on specific inclusion criteria. Articles chosen for this systematic review were between January 2008 and December 2018. Relevant articles were identified through an extensive search in Science Direct, PubMed, Google Scholar and Scopus. The literature searches of the electronic databases combined the following key words: anti-angiogenic, anticancer, Zerumbone and Zingiber zerumbet. Studies chosen for this review includes the following designs in vitro, in vivo and ex vivo. The initial literature search obtained a total of 352 related records and the final number of studies that met the inclusion criteria in the current review was 43 studies. In vitro studies were the commonest study design. Evidently, Zerumbone demonstrate a potential antiproliferative and antiangiogenic. The antiproliferative activities of Zerumbone was shown to induce by different signalling pathway. Zerumbone through its antiangiogenic effect play a great role in reducing invasion and metastasis. Some selected studies on Zerumbone were found to plague with limitation such as lack of toxic threshold value which may be needed for the clinical trials on this compound.

Essential Oils and Their Main Chemical Components: The Past 20 Years of Preclinical Studies in Melanoma

Simple Summary

In the last years, targeted therapy and immunotherapy modified the landscape for metastatic melanoma treatment. These therapeutic approaches led to an impressive improvement in patients overall survival. Unfortunately, the emergence of drug resistance and side effects occurring during therapy strongly limit the long-term efficacy of such treatments. Several preclinical studies demonstrate the efficacy of essential oils as antitumoral agents, and clinical trials support their use to reduce side effects emerging during therapy. In this review we have summarized studies describing the molecular mechanism through which essential oils induce in vitro and in vivo cell death in melanoma models. We also pointed to clinical trials investigating the use of essential oils in reducing the side effects experienced by cancer patients or those undergoing anticancer therapy. From this review emerged that further studies are necessary to validate the effectiveness of essential oils for the management of melanoma.

Abstract

The last two decades have seen the development of effective therapies, which have saved the lives of a large number of melanoma patients. However, therapeutic options are still limited for patients without BRAF mutations or in relapse from current treatments, and severe side effects often occur during therapy. Thus, additional insights to improve treatment efficacy with the aim to decrease the likelihood of chemoresistance, as well as reducing side effects of current therapies, are required. Natural products offer great opportunities for the discovery of antineoplastic drugs, and still represent a useful source of novel molecules. Among them, essential oils, representing the volatile fraction of aromatic plants, are always being actively investigated by several research groups and show promising biological activities for their use as complementary or alternative medicine for several diseases, including cancer. In this review, we focused on studies reporting the mechanism through which essential oils exert antitumor action in preclinical wild type or mutant BRAF melanoma models. We also discussed the latest use of essential oils in improving cancer patients’ quality of life. As evidenced by the many studies listed in this review, through their effect on apoptosis and tumor progression-associated properties, essential oils can therefore be considered as potential natural pharmaceutical resources for cancer management.

Oxidative stress and antioxidants in the pathophysiology of malignant melanoma

The high number of somatic mutations in the melanoma genome associated with cumulative ultra violet (UV) exposure has rendered it one of the most difficult of cancers to treat. With new treatment approaches based on targeted and immune therapies, drug resistance has appeared as a consistent problem. Redox biology, including reactive oxygen and nitrogen species (ROS and RNS), plays a central role in all aspects of melanoma pathophysiology, from initiation to progression and to metastatic cells. The involvement of melanin production and UV radiation in ROS/RNS generation has rendered the melanocytic lineage a unique system for studying redox biology. Overall, an elevated oxidative status has been associated with melanoma, thus much effort has been expended to prevent or treat melanoma using antioxidants which are expected to counteract oxidative stress. The consequence of this redox-rebalance seems to be two-fold: on the one hand, cells may behave less aggressively or even undergo apoptosis; on the other hand, cells may survive better after being disseminated into the circulating system or after drug treatment, thus resulting in metastasis promotion or further drug resistance. In this review we summarize the current understanding of redox signaling in melanoma at cellular and systemic levels and discuss the experimental and potential clinic use of antioxidants and new epigenetic redox modifiers.

Gingers and Their Purified Components as Cancer Chemopreventative Agents

Chemoprevention by ingested substituents is the process through which nutraceuticals and/or their bioactive components antagonize carcinogenesis. Carcinogenesis is the course of action whereby a normal cell is transformed into a neoplastic cell. This latter action involves several steps, starting with initiation and followed by promotion and progression. Driving these stages is continued oxidative stress and inflammation, which in turn, causes a myriad of aberrant gene expressions and mutations within the transforming cell population and abnormal gene expressions by the cells within the surrounding lesion. Chemoprevention of cancer with bioreactive foods or their extracted/purified components occurs primarily via normalizing these inappropriate gene activities. Various foods/agents have been shown to affect different gene expressions. In this review, we discuss how the chemoprevention activities of gingers antagonize cancer development.

Potential of Zerumbone as an Anti-Cancer Agent

Cancer is still a major risk factor to public health globally, causing approximately 9.8 million deaths worldwide in 2018. Despite advances in conventional treatment modalities for cancer treatment, there are still few effective therapies available due to the lack of selectivity, adverse side effects, non-specific toxicities, and tumour recurrence. Therefore, there is an immediate need for essential alternative therapeutics, which can prove to be beneficial and safe against cancer. Various phytochemicals from natural sources have been found to exhibit beneficial medicinal properties against various human diseases. Zerumbone is one such compound isolated from Zingiber zerumbet Smith that possesses diverse pharmacological properties including those of antioxidant, antibacterial, antipyretic, anti-inflammatory, immunomodulatory, as well as anti-neoplastic. Zerumbone has shown its anti-cancer effects by causing significant suppression of proliferation, survival, angiogenesis, invasion, and metastasis through the molecular modulation of different pathways such as NF-κB, Akt, and IL-6/JAK2/STAT3 (interleukin-6/janus kinase-2/signal transducer and activator of transcription 3) and their downstream target proteins. The current review briefly summarizes the modes of action and therapeutic potential of zerumbone against various cancers.

Essential oils: from prevention to treatment of skin cancer

The increasing incidence of cutaneous malignancies signifies the need for multiple treatment options. Several available reviews have emphasized the potential role of various botanical extracts and naturally occurring compounds as anti-skin-cancer agents. Few studies relate to the role of chemoprevention and therapeutic activity of essential oils (EOs) and EO components. The present review summarizes an overview of chemopreventive, anti-melanoma and anti-nonmelanoma activities of EOs from various plants and EO components in in vitro and in vivo models with special emphasis on skin cancer. Also, the mechanisms by which EOs and EO components exert their effects to induce cell death are presented.