humulene and Colonic-Neoplasms

The present study is designed to find out if sesquiterpenes, α-humulene (HUM), valencene (VAL), β-caryphyllene-oxide (CAO) and trans-nerolidol (NER), are able to improve the antiproliferative effect of classical cytostatic drugs, 5-fluorouracil (FU) and oxaliplatin (1,2-diaminocyclohexaneoxalato-platinum, OxPt), in colon cancer cell lines Caco-2 and SW-620. In addition, the possible mechanisms of sesquiterpene action are studied. The results show significant ability of HUM and especially of CAO to enhance the anti-proliferative effects of FU and OxPt in cancer cell lines Caco-2 and SW-620. On the other hand, VAL and NER are ineffective. The action of CAO could be partly based on its ability to disrupt the mitochondrial membrane potential and to activate initiator caspases, but other mechanisms are probably also involved. Based on these results, CAO seems to have the potential for combination therapy of colon cancers and deserves further study.

Topics: Caco-2 Cells; Cell Line, Tumor; Cell Proliferation; Colonic Neoplasms; Fluorouracil; Humans; Membrane Potential, Mitochondrial; Monocyclic Sesquiterpenes; Oxaliplatin; Polycyclic Sesquiterpenes; Sesquiterpenes

Colon cancer is a major public health problem. Cannabis-based medicines are useful adjunctive treatments in cancer patients. Here, we have investigated the effect of a standardized Cannabis sativa extract with high content of cannabidiol (CBD), here named CBD BDS, i.e. CBD botanical drug substance, on colorectal cancer cell proliferation and in experimental models of colon cancer in vivo.. Proliferation was evaluated in colorectal carcinoma (DLD-1 and HCT116) as well as in healthy colonic cells using the MTT assay. CBD BDS binding was evaluated by its ability to displace [(3)H]CP55940 from human cannabinoid CB1 and CB2 receptors. In vivo, the effect of CBD BDS was examined on the preneoplastic lesions (aberrant crypt foci), polyps and tumours induced by the carcinogenic agent azoxymethane (AOM) as well as in a xenograft model of colon cancer in mice.. CBD BDS and CBD reduced cell proliferation in tumoral, but not in healthy, cells. The effect of CBD BDS was counteracted by selective CB1 and CB2 receptor antagonists. Pure CBD reduced cell proliferation in a CB1-sensitive antagonist manner only. In binding assays, CBD BDS showed greater affinity than pure CBD for both CB1 and CB2 receptors, with pure CBD having very little affinity. In vivo, CBD BDS reduced AOM-induced preneoplastic lesions and polyps as well as tumour growth in the xenograft model of colon cancer.. CBD BDS attenuates colon carcinogenesis and inhibits colorectal cancer cell proliferation via CB1 and CB2 receptor activation. The results may have some clinical relevance for the use of Cannabis-based medicines in cancer patients.

Topics: Animals; Azoxymethane; Cannabidiol; Cannabinoid Receptor Antagonists; Cannabis; Carcinogenesis; Carcinoma; Cell Proliferation; Cell Survival; CHO Cells; Colonic Neoplasms; Cricetinae; Cricetulus; Epithelial Cells; HCT116 Cells; Humans; Male; Mice, Inbred ICR; Phytotherapy; Plant Extracts; Random Allocation; Receptors, Cannabinoid; Xenograft Model Antitumor Assays

Cannabigerol (CBG) is a safe non-psychotropic Cannabis-derived cannabinoid (CB), which interacts with specific targets involved in carcinogenesis. Specifically, CBG potently blocks transient receptor potential (TRP) M8 (TRPM8), activates TRPA1, TRPV1 and TRPV2 channels, blocks 5-hydroxytryptamine receptor 1A (5-HT1A) receptors and inhibits the reuptake of endocannabinoids. Here, we investigated whether CBG protects against colon tumourigenesis. Cell growth was evaluated in colorectal cancer (CRC) cells using the 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyl tetrazolium bromide and 3-amino-7-dimethylamino-2-methylphenazine hydrochloride assays; apoptosis was examined by histology and by assessing caspase 3/7 activity; reactive oxygen species (ROS) production by a fluorescent probe; CB receptors, TRP and CCAAT/enhancer-binding protein homologous protein (CHOP) messenger RNA (mRNA) expression were quantified by reverse transcription-polymerase chain reaction; small hairpin RNA-vector silencing of TRPM8 was performed by electroporation. The in vivo antineoplastic effect of CBG was assessed using mouse models of colon cancer. CRC cells expressed TRPM8, CB1, CB2, 5-HT1A receptors, TRPA1, TRPV1 and TRPV2 mRNA. CBG promoted apoptosis, stimulated ROS production, upregulated CHOP mRNA and reduced cell growth in CRC cells. CBG effect on cell growth was independent from TRPA1, TRPV1 and TRPV2 channels activation, was further increased by a CB2 receptor antagonist, and mimicked by other TRPM8 channel blockers but not by a 5-HT1A antagonist. Furthermore, the effect of CBG on cell growth and on CHOP mRNA expression was reduced in TRPM8 silenced cells. In vivo, CBG inhibited the growth of xenograft tumours as well as chemically induced colon carcinogenesis. CBG hampers colon cancer progression in vivo and selectively inhibits the growth of CRC cells, an effect shared by other TRPM8 antagonists. CBG should be considered translationally in CRC prevention and cure.

Topics: Animals; Apoptosis; Azoxymethane; Blotting, Western; Cannabinoids; Cannabis; Carcinogens; Cell Proliferation; Cells, Cultured; Colon; Colonic Neoplasms; Flow Cytometry; Humans; Immunoenzyme Techniques; Male; Mice; Mice, Inbred ICR; Mice, Nude; Reactive Oxygen Species; Real-Time Polymerase Chain Reaction; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; RNA, Small Interfering; TRPM Cation Channels; Xenograft Model Antitumor Assays

It is well known that various cytokines such as interleukin-8 (IL-8) and tumor necrosis factor-alpha (TNF-alpha are expressed and secreted from intestinal epithelial cells and that these cytokines affect the immune cells beneath the intestinal epithelial monolayers. As the secretion of these cytokines is likely to be regulated by food-derived substances, we focused on those food substances which regulate the secretion of IL-8 in human intestinal epithelial Caco-2 cells. 72 food samples extracted with 40% ethanol were tested, and the extracts of peppermint and dokudami significantly increased the IL-8 secretion. Among the compounds known to be contained in peppermint and dokudami, alpha-humulene substantially increased the IL-8 secretion.alpha-Humulene had no significant effect on the secretion of such other soluble factors as TNF-alpha, IL-1beta, IL-6, or NGF, suggesting that the effect of alpha-humulene was specific for IL-8 secretion. The expression level of IL-8 mRNA was significantly increased by treating with alpha-humulene. These results suggest that the secretion of IL-8 by alpha-humulene is regulated at the transcriptional level.

Topics: Cell Line, Tumor; Colonic Neoplasms; Food Analysis; Gene Expression Regulation, Neoplastic; Humans; Interleukin-8; Intestinal Mucosa; Monocyclic Sesquiterpenes; Sesquiterpenes