“Chemotherapy resistance is an insurmountable problem in clinical anticancer therapy. Although Oxaliplatin is an effective chemotherapeutic agent for the treatment of colorectal cancer (CRC), it still suffers from serious toxicities as well as drug resistance. In this work, three Oxaliplatin tetravalent platinum prodrugs(O1-O3) and three novel mixed ammine/amine analogs(C1-C3) were constructed, introducing cannabidiol with anti-tumor activity in their axial position.

All Pt(IV) prodrugs exhibited potent antitumor effects in a variety of tumor cell lines, especially in HCT-116 cells, where complex O3 showed strong inhibitory effects with the half maximal inhibitory concentrations (IC₅₀) value of 6.02 ± 0.69 μM and about 2.6 times higher than that of Oxaliplatin. Further studies revealed that complex O3 decreased cellular mitochondrial membrane potential in a concentration-dependent manner and enhanced reactive oxygen species (ROS) accumulation by decreasing the expression of catalase, superoxide dismutase 2 (SOD2) and superoxide dismutase 3 (SOD3). Complex O3 induces mitochondrial dysfunction and upregulates the pro-apoptotic protein Noxa, ultimately leading to severe DNA damage. The upregulation of Phosphorylated histone protein H2AX (γ-H2AX) expression is clear evidence. In addition, O3 inhibits the expression of RAD51 protein and prevents DNA damage repair, thus overcoming drug resistance.

This strategy of combining bioactive molecules cannabidiol with platinum drugs to improve therapeutic efficacy and overcome drug resistance has been proven to be very effective and deserves further investigation.”

https://pubmed.ncbi.nlm.nih.gov/38490045/

“The cannabidiol was introduced into the platinum antitumor drugs, and the Pt(IV) complexes O1-O3 and C1- C3 were synthesized.

•Complex O3 is highly cytotoxic to all cancer cells and cannabidiol exerts a synergistic antitumor effect with Oxaliplatin.”

https://www.sciencedirect.com/science/article/abs/pii/S0162013424000382?via%3Dihub

“Mitogen-activated protein kinase (MAPK) activation by natural compounds is known to be involved in the induction of apoptosis, paraptosis, and autophagy.

Cannabidiol (CBD), a bioactive compound found in Cannabis sativa, is endowed with many pharmacological activities. We investigated the cytotoxic effect of CBD in a panel of colorectal cancer (CRC) cells (HT-29, SW480, HCT-116, and HCT-15).

CBD induced significant cytotoxicity as evidenced by the results of MTT assay, live-dead assay, and flow cytometric analysis. Since CBD displayed cytotoxicity against CRC cells, we examined the effect of CBD on apoptosis, paraptosis, and autophagy. CBD decreased the expression of antiapoptotic proteins and increased the Annexin-V-positive as well as TUNEL-positive cells suggesting that CBD induces apoptosis. CBD increased the expression of ATF4 (activating transcription factor 4) and CHOP (CCAAT/enhancer-binding protein homologous protein), elevated endoplasmic reticulum stress, and enhanced reactive oxygen species levels indicating that CBD also promotes paraptosis. CBD also induced the expression of Atg7, phospho-Beclin-1, and LC3 suggesting that CBD also accelerates autophagy.

Since, the MAPK pathway is a common cascade that is involved in the regulation of apoptosis, paraptosis, and autophagy, we investigated the effect of CBD on the activation of JNK, p38, and ERK pathways. CBD activated all the forms of MAPK proteins and pharmacological inhibition of these proteins reverted the observed effects.

Our findings implied that CBD could induce CRC cell death by activating apoptosis, paraptosis, and autophagy through the activation of the MAPK pathway.”

https://pubmed.ncbi.nlm.nih.gov/38358093/

https://onlinelibrary.wiley.com/doi/10.1002/jcb.30537

“Cannabidiol (CBD) is a chemical obtained from Cannabis sativa; it has therapeutic effects on anxiety and cognition and anti-inflammatory properties. Although pharmacological applications of CBD in many types of tumors have recently been reported, the mechanism of action of CBD is not yet fully understood. In this study, we perform an mRNA-seq analysis to identify the target genes of CBD after determining the cytotoxic concentrations of CBD using an MTT assay. CBD treatment regulated the expression of genes related to DNA repair and cell division, with metallothionein (MT) family genes being identified as having highly increased expression levels induced by CBD. It was also found that the expression levels of MT family genes were decreased in colorectal cancer tissues compared to those in normal tissues, indicating that the downregulation of MT family genes might be highly associated with colorectal tumor progression. A qPCR experiment revealed that the expression levels of MT family genes were increased by CBD. Moreover, MT family genes were regulated by CBD or crude extract but not by other cannabinoids, suggesting that the expression of MT family genes was specifically induced by CBD. A synergistic effect between CBD and MT gene transfection or zinc ion treatment was found. In conclusion, MT family genes as novel target genes could synergistically increase the anticancer activity of CBD by regulating the zinc ions in human colorectal cancer cells.”

https://pubmed.ncbi.nlm.nih.gov/38068944/

“In conclusion, CBD requires the expression of MT family genes for its anticancer activity during cancer treatment, suggesting that CBD can affect the expression of genes involved in zinc homeostasis via MT family gene expression. These current results suggest that the regulation of zinc levels could play an important role in allowing CBD to exert enhanced anticancer effects. Although CBD treatment has shown anticancer effects on many types of cancers, its molecular mechanism remains unclear. In this study, we explained the possible interactions of MT genes, metal ions, and CBD for anticancer effects. The results of this study might provide an important clue for uncovering the mechanisms involved in the anticancer effects of CBD, such as through the regulation of intracellular homeostasis of metal ions.”

https://www.mdpi.com/1422-0067/24/23/16621

“Phenolic compounds from Cannabis sativa L. (Cannabaceae family), in particular cannflavins, are known to possess several biological properties. However, their antiproliferative activity, being of great interest from a medicinal chemistry point of view, has not been deeply investigated so far in the literature. In the light of this, the aim of this study was to obtain an enriched fraction of polyphenols (namely PEF) from inflorescences of a non-psychoactive C. sativa (hemp) variety and to evaluate its antiproliferative activity against cancer cells, capitalizing on a new and selective extraction method for hemp polyphenols, followed by preparative flash column chromatography. Untargeted metabolomics, using a new method based on ultra-high-performance liquid chromatography coupled with high-resolution mass spectrometry (UHPLC-HRMS), was applied here for the first time to fully characterize PEF. Then, the main phenolic compounds were quantified by HPLC-UV. The antiproliferative activity of PEF and of the isolated compounds was assessed in vitro for the first time against Caco-2 and SW480 human colon adenocarcinoma cell lines providing promising IC₅₀ values, in comparison with the reference drug used in therapy for this cancer type. Based on these results, PEF can be considered as a new highly potential therapeutic product to be further investigated against colorectal cancer, thanks to the possible synergistic interaction of its compounds.”

https://pubmed.ncbi.nlm.nih.gov/37748359/

https://www.sciencedirect.com/science/article/pii/S0731708523004922?via%3Dihub

“Colorectal tumors often create an immunosuppressive microenvironment that prevents them from responding to immunotherapy.

Cannabidiol (CBD) is a non-psychoactive natural active ingredient from the cannabis plant that has various pharmacological effects, including neuroprotective, antiemetic, anti-inflammatory, and antineoplastic activities.

This study aimed to elucidate the specific anticancer mechanism of CBD by single-cell RNA sequencing (scRNA-seq) and single-cell ATAC sequencing (scATAC-seq) technologies.

Here, we report that CBD inhibits colorectal cancer progression by modulating the suppressive tumor microenvironment (TME).

Our single-cell transcriptome and ATAC sequencing results showed that CBD suppressed M2-like macrophages and promoted M1-like macrophages in tumors both in strength and quantity. Furthermore, CBD significantly enhanced the interaction between M1-like macrophages and tumor cells and restored the intrinsic anti-tumor properties of macrophages, thereby preventing tumor progression. Mechanistically, CBD altered the metabolic pattern of macrophages and related anti-tumor signaling pathways.

We found that CBD inhibited the alternative activation of macrophages and shifted the metabolic process from oxidative phosphorylation and fatty acid oxidation to glycolysis by inhibiting the phosphatidylinositol 3-kinase-protein kinase B signaling pathway and related downstream target genes. Furthermore, CBD-mediated macrophage plasticity enhanced the response to anti-programmed cell death protein-1 (PD-1) immunotherapy in xenografted mice.

Taken together, we provide new insights into the anti-tumor effects of CBD.”

https://pubmed.ncbi.nlm.nih.gov/37577382/

“CBD shapes the TME to prevent tumor progression.”

https://www.sciencedirect.com/science/article/pii/S2095177923000746?via%3Dihub

“Although it has been established that cannabidiol (CBD), the major non-psychoactive constituent of cannabis, exerts antitumoral activities, the exact mechanism(s) via which tumor cells are killed by CBD are not well understood.

This study provides new insights into the potential mechanisms of CBD-induced mutual antagonism of apoptosis and macroautophagy using wild type (HCT116 p53wt, LS174T p53wt), knockout (HCT116 p53^-/-) and mutant (SW480 p53mut) human colorectal cancer cells (CRC).

CBD causes a more pronounced loss in the viability of p53wt cells than p53^-/- and p53mut cells, and a 5-week treatment with CBD reduced the volume of HCT116 p53wt xenografts in mice, but had no effect on the volume of HCT116 p53^-/- tumors.

Mechanistically, we demonstrate that CBD only significantly elevates ROS production in cells harboring wild-type p53 (HCT116, LS174T) and that this is associated with an accumulation of PARP1. CBD-induced elevated ROS levels trigger G0/G1 cell cycle arrest, a reduction in CDK2, a p53-dependent caspase-8/9/3 activation and macroautophagy in p53wt cells. The ROS-induced macroautophagy which promotes the activation of keap1/Nrf2 pathway might be positively regulated by p53wt, since inhibition of p53 by pifithrin-α further attenuates autophagy after CBD treatment.

Interestingly, an inhibition of heat shock protein 70 (Hsp70) expression significantly enhances caspase-3 mediated programmed cell death in p53wt cells, whereas autophagy-which is associated with a nuclear translocation of Nrf2-was blocked.

Taken together, our results demonstrate an intricate interplay between apoptosis and macroautophagy in CBD-treated colorectal cancer cells, which is regulated by the complex interactions of p53wt and Hsp70.”

https://pubmed.ncbi.nlm.nih.gov/37542074/

https://www.nature.com/articles/s41420-023-01578-9