Cannabidiol promotes apoptosis via regulation of XIAP/Smac in gastric cancer

Network pharmacology‑based analysis and in vitro experimental verification of the inhibitory role of luteoloside on gastric cancer cells via the p53/p21 pathway

The present study aimed to investigate the inhibitory effect of luteoloside on the proliferation, migration and invasion of gastric cancer (GC) cells based on network pharmacology and in vitro experiments. GC-associated targets were obtained from the GeneCards and Online Mendelian Inheritance in Man databases. Gene Ontology functional enrichment analysis and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis were performed using the Database for Annotation, Visualization and Integrated Discovery. Protein-protein interaction (PPI) networks and herb-active ingredient-target gene-signaling pathway networks were constructed using the Search Tool for the Retrieval of Interacting Genes and proteins and Cytoscape software to analyze core target genes and pathways. In addition, the alkaline comet assay was performed to assess DNA damage, demonstrating that luteoloside induces DNA double-strand breaks in a concentration-dependent manner, as indicated by increased comet tail lengths. γ-H2AX detection through western blot analysis further corroborated these findings, showing significant upregulation of this DNA damage marker in luteoloside-treated GC cells. The human GC cell line NCI-N87 was utilized for in vitro experiments to investigate the impact of different doses of luteoloside on cell proliferation, invasion and migration using Cell Counting Kit-8, scratch-wound and Transwell assays, respectively. The underlying molecular mechanism of luteoloside was explored using western blot analysis. The successfully constructed PPI network revealed the p53, Akt1, Bcl-2 and Caspase-3 proteins as the core targets, all of which showed good binding activity with luteoloside. The in vitro experiments demonstrated that luteoloside treatment significantly inhibited GC-cell proliferation, migration and invasion. The western blot results showed notable concentration-dependent upregulation of p53 and p21 protein expression and downregulation of Bcl-2 protein expression following luteoloside treatment. Overall, luteoloside inhibited the proliferation, migration and invasion of GC cells by activating the p53/p21 signaling pathway.

Full-spectrum cannabidiol reduces UVB damage through the inhibition of TGF-β1 and the NLRP3 inflammasome

The thermodynamic characteristics, antioxidant potential, and photoprotective benefits of full-spectrum cannabidiol (FS-CBD) against UVB-induced cellular death were examined in this study. In silico analysis of CBD showed antioxidant capacity via proton donation and UV absorption at 209.09, 254.73, and 276.95 nm, according to the HAT and SPLET methodologies. FS-CBD protected against UVB-induced bacterial death for 30 min. FS-CBD protected against UVB-induced cell death by 42% (1.5 μg/mL) and 35% (3.5 μg/mL) in an in vitro keratinocyte cell model. An in vivo acute irradiated CD-1et/et mouse model (UVB-irradiated for 5 min) presented very low photoprotection when FS-CBD was applied cutaneously, as determined by histological analyses. In vivo skin samples showed that FS-CBD regulated inflammatory responses by inhibiting the inflammatory markers TGF-β1 and NLRP3. The docking analysis showed that the CBD molecule had a high affinity for TGF-β1 and NLRP3, indicating that protection against inflammation might be mediated by blocking these proinflammatory molecules. This result was corroborated by the docking interactions between CBD and TGF-β1 and NLRP3, which resulted in a high affinity and inhibition of both proteins The present work suggested a FS-CBD moderate photoprotective agent against UVB light-induced skin damage and that this effect is partially mediated by its anti-inflammatory activity.

Cannabidiol Enhances Atezolizumab Efficacy by Upregulating PD-L1 Expression via the cGAS-STING Pathway in Triple-Negative Breast Cancer Cells

The treatment of patients with triple-negative breast cancer (TNBC) relies on cytotoxic therapy. Currently, atezolizumab and chemotherapy can be combined in patients with TNBC. However, this approach is not effective for all patients, with many tumors showing low responsiveness to atezolizumab. As there is a lack of alternative treatment options, new anticancer drugs are urgently needed to enhance atezolizumab activity against TNBC. Recent strategies have focused on regulating the expression of programmed cell death ligand 1 (PD-L1) or enhancing immune response activation by combining anticancer drugs with immune checkpoint inhibitors. Cannabidiol (CBD), a cannabinoid component derived from the cannabis plant, has been reported to have anticancer therapeutic potential because of its capacity to induce apoptotic cell death in tumor cells while avoiding cytotoxicity in normal cells. Previous studies have demonstrated the effects of CBD on apoptosis in various cancer cell types. However, the potential role of CBD as an immune modulator in the regulation of PD-L1 expression and anticancer immune responses remains to be explored. In this study, we found that CBD stimulated PD-L1 expression in TNBC cells and that this occurred downstream of CBD-mediated cyclic guanosine monophosphate-adenosine monophosphate synthase-stimulator of interferon genes (cGAS-STING) pathway activation. Taken together, we have demonstrated that the combination of CBD and anti-PD-L1 enhances the anticancer immune responses in in vitro and in vivo experiments. Our findings identified the mechanism of PD-L1 regulation by CBD in TNBC cells and suggested that CBD could be a potential candidate for the development of new combinatorial strategies with immune checkpoint inhibitors in patients with TNBC.

LINC02139 interacts with and stabilizes XIAP to regulate cell proliferation and apoptosis in gastric cancer

Previous reports showed that long non-coding RNA (lncRNA) participates in the development and progression of tumors. Nevertheless, the effect of LINC02139 and its mechanism on gastric cancer (GC) is still unknown. We revealed that LINC02139 is upregulated in GC cell lines and tissues and high LINC02139 expression was correlated with the advancement of GC in patients. Functionally, overexpression of LINC02139 promoted, while knockdown of LINC02139 impaired GC cell proliferation, migration, and invasion in vitro and impeded tumorigenesis in a tumor xenograft model in vivo. Mechanistically, LINC02139 directly bound to XIAP and increased the protein level by maintaining its protein stability through inhibition of the ubiquitination and proteasome-dependent degradation pathway. Importantly, the regulatory function of XIAP in LINC02139-mediated oncogenic effects was demonstrated. Both in vitro and in vivo experiments showed that LINC02139 and XIAP collaboratively modulate GC cell growth and apoptosis. Analysis of clinical GC tissues further confirmed the upregulation of XIAP and the positive association between LINC02139 and XIAP expression. These findings established LINC02139 as a driver of tumorigenesis and highlighted the crucial involvement of the LINC02139-XIAP axis in GC progression, suggesting its potential as a promising therapeutic target for combating GC advancement.

The molecular anti-metastatic potential of CBD and THC from Lebanese Cannabis via apoptosis induction and alterations in autophagy

The medicinal plant Cannabis sativa L. (C. sativa) is currently being extensively studied to determine the full extent of its therapeutic pharmacological potential. Δ9-tetrahydocannabinol (THC) and cannabidiol (CBD) are the most thoroughly investigated compounds. We aimed to explore the anticancer activity of cannabinoids mixture isolated from the Lebanese C. sativa plant in ratios comparable to the local medicinal plant, to elucidate its mechanism of action in breast cancer cells in vitro. Cells were subjected to cytotoxicity assay, cell cycle analysis, Annexin V/PI dual staining, cell death ELISA, immunofluorescence, in addition to western blot analysis of apoptotic and autophagy markers. We further evaluated the anti-metastatic effect of cannabinoids on MDA-MB-231 using the scratch wound-healing, trans-well migration and invasion assays. Our results revealed the promising therapeutic benefits of CBD/THC on inhibiting the growth of breast cancer cells by promoting cellular fragmentation, phosphatidylserine translocation to the outer membrane leaflet and DNA fragmentation in both cell lines while inhibiting the motility of the triple negative breast cancer cells. In our study, CBD/THC mixture was found to exhibit a pro-apoptotic activity via the activation of the mitochondrial apoptotic pathway, independent from ROS production while also suggesting the activation of a caspase-dependent apoptotic pathway. Even though autophagy was altered upon exposure to the cannabinoid mixture, our data suggested that it is not the mechanism responsible of inducing cell death. In conclusion, our study demonstrates the promising therapeutic benefits of CBD and THC isolated from the Lebanese C. sativa plant on breast cancer cells in vitro.

Toxicity of cannabidiol and its metabolites in TM3 mouse Leydig cells: a comparison with primary human Leydig cells

Cannabidiol (CBD), one of the major components extracted from the plant Cannabis sativa L., has been used as a prescription drug to treat seizures in many countries. CBD-induced male reproductive toxicity has been reported in animal models; however, the underlying mechanisms remain unclear. We previously reported that CBD induced apoptosis in primary human Leydig cells, which constitute the primary steroidogenic cell population in the testicular interstitium. In this study, we investigated the effects of CBD and its metabolites on TM3 mouse Leydig cells. CBD, at concentrations below 30 µM, reduced cell viability, induced G1 cell cycle arrest, and inhibited DNA synthesis. CBD induced apoptosis after exposure to high concentrations (≥ 50 µM) for 24 h or a low concentration (20 µM) for 6 days. 7-Hydroxy-CBD and 7-carboxy-CBD, the main CBD metabolites of CBD, exhibited the similar toxic effects as CBD. In addition, we conducted a time-course mRNA-sequencing analysis in both primary human Leydig cells and TM3 mouse Leydig cells to understand and compare the mechanisms underlying CBD-induced cytotoxicity. mRNA-sequencing analysis of CBD-treated human and mouse Leydig cells over a 5-day time-course indicated similar responses in both cell types. Mitochondria and lysosome dysfunction, oxidative stress, and autophagy were the major enriched pathways in both cell types. Taken together, these findings demonstrate comparable toxic effects and underlying mechanisms in CBD-treated mouse and primary human Leydig cells.

Melanoma and cannabinoids: A possible chance for cancer treatment

The endocannabinoid system is composed by a complex and ubiquitous network of endogenous lipid ligands, enzymes for their synthesis and degradation, and receptors, which can also be stimulated by exogenous compounds, such as those derived from the Cannabis sativa. Cannabis and its bioactive compounds, including cannabinoids and non-cannabinoids, have been extensively studied in different conditions. Recent data have shown that the endocannabinoid system is responsible for maintaining the homeostasis of various skin functions such as proliferation, differentiation and release of inflammatory mediators. Because of their role in regulating these key processes, cannabinoids have been studied for the treatment of skin cancers and melanoma; their anti-tumour effects regulate skin cancer progression and are mainly related to the inhibition of tumour growth, proliferation, invasion and angiogenesis, through apoptosis and autophagy induction. This review aims at summarising the current field of research on the potential uses of cannabinoids in the melanoma field.

Advances and Challenges in Modeling Cannabidiol Pharmacokinetics and Hepatotoxicity

Cannabidiol (CBD) is a pharmacologically active metabolite of cannabis that is US Food and Drug Administration approved to treat seizures associated with Lennox-Gastaut syndrome, Dravet syndrome, and tuberous sclerosis complex in children aged 1 year and older. During clinical trials, CBD caused dose-dependent hepatocellular toxicity at therapeutic doses. The risk for toxicity was increased in patients taking valproate, another hepatotoxic antiepileptic drug, through an unknown mechanism. With the growing popularity of CBD in the consumer market, an improved understanding of the safety risks associated with CBD is needed to ensure public health. This review details current efforts to describe CBD pharmacokinetics and mechanisms of hepatotoxicity using both pharmacokinetic models and in vitro models of the liver. In addition, current evidence and knowledge gaps related to intracellular mechanisms of CBD-induced hepatotoxicity are described. The authors propose future directions that combine systems-based models with markers of CBD-induced hepatotoxicity to understand how CBD pharmacokinetics may influence the adverse effect profile and risk of liver injury for those taking CBD. SIGNIFICANCE STATEMENT: This review describes current pharmacokinetic modeling approaches to capture the metabolic clearance and safety profile of cannabidiol (CBD). CBD is an increasingly popular natural product and US Food and Drug Administration-approved antiepileptic drug known to cause clinically significant enzyme-mediated drug interactions and hepatotoxicity at therapeutic doses. CBD metabolism, pharmacokinetics, and putative mechanisms of CBD-induced liver injury are summarized from available preclinical data to inform future modeling efforts for understanding CBD toxicity.

Cannabinoids induce cell death in leukaemic cells through Parthanatos and PARP-related metabolic disruptions

BACKGROUND

Several studies have described a potential anti-tumour effect of cannabinoids (CNB). CNB receptor 2 (CB2) is mostly present in hematopoietic stem cells (HSC). The present study evaluates the anti-leukaemic effect of CNB.

METHODS

Cell lines and primary cells from acute myeloid leukaemia (AML) patients were used and the effect of the CNB derivative WIN-55 was evaluated in vitro, ex vivo and in vivo.

RESULTS

We demonstrate a potent antileukemic effect of WIN-55 which is abolished with CB antagonists. WIN-treated mice, xenografted with AML cells, had better survival as compared to vehicle or cytarabine. DNA damage-related genes were affected upon exposure to WIN. Co-incubation with the PARP inhibitor Olaparib prevented WIN-induced cell death, suggesting PARP-mediated apoptosis which was further confirmed with the translocation of AIF to the nucleus observed in WIN-treated cells. Nicotinamide prevented WIN-related apoptosis, indicating NAD+ depletion. Finally, WIN altered glycolytic enzymes levels as well as the activity of G6PDH. These effects are reversed through PARP1 inhibition.

CONCLUSIONS

WIN-55 exerts an antileukemic effect through Parthanatos, leading to translocation of AIF to the nucleus and depletion of NAD+, which are reversed through PARP1 inhibition. It also induces metabolic disruptions. These effects are not observed in normal HSC.

Research Progress on the Mechanism of the Antitumor Effects of Cannabidiol

Cannabidiol (CBD), a non-psychoactive ingredient extracted from the hemp plant, has shown therapeutic effects in a variety of diseases, including anxiety, nervous system disorders, inflammation, and tumors. CBD can exert its antitumor effect by regulating the cell cycle, inducing tumor cell apoptosis and autophagy, and inhibiting tumor cell invasion, migration, and angiogenesis. This article reviews the proposed antitumor mechanisms of CBD, aiming to provide references for the clinical treatment of tumor diseases and the rational use of CBD.

Construction and validation of a novel tumor necrosis factor-related apoptosis-inducing ligand mutant MuR5S4-TR

AIM

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) can selectively kill tumor cells but has no significant effect on normal cells. However, the use of TRAIL is limited for resistance by more than 50% of the tumor cell lines. It's very important to develop a more efficient form of TRAIL for cancer treatment.

METHODS

The N-terminal in soluble fragments (114-281aa) of TRAIL was redesigned to construct a novel TRAIL mutant-MuR5S4-TR. The Cell Counting Kit-8 method to explore the antitumor effects. The potential mechanisms were also explored.

RESULTS

Novel TRAIL mutant with cell-penetrating peptides (CPP) like and Second mitochondria-derived activator of caspases (Smac) like structure-MuR5S4-TR was successfully constructed. The prokaryotic expression system was successfully built, and the MuR5S4-TR was purified and reconfirmed by western blot. MuR5S4-TR could enhance the antitumor effects of TRAIL in most of the cancer cell lines significantly, NCI-H460 lung cancer cell line, for instance. After MuR5S4-TR treatment, the expressions of death receptor 4 (DR4), DR5, Caspase-8, and cleaved Caspase-3 were remarkably increased, however, there was no significant difference in X-linked inhibitor of apoptosis expression.

CONCLUSION

We constructed a novel TRAIL mutant with CPP-like and Smac-like structure-MuR5S4-TR. The MuR5S4-TR showed significantly stronger antitumor effects than TRAIL in many tumor cell lines. The MuR5S4-TR showed strong antitumor effects both in vitro and in vivo. This preliminary study implies that MuR5S4-TR may be a more efficient form of TRAIL for cancer therapy.

Cannabidiol Disrupts Mitochondrial Respiration and Metabolism and Dysregulates Trophoblast Cell Differentiation

Trophoblast differentiation is a crucial process in the formation of the placenta where cytotrophoblasts (CTs) differentiate and fuse to form the syncytiotrophoblast (ST). The bioactive components of cannabis, such as Δ9-THC, are known to disrupt trophoblast differentiation and fusion, as well as mitochondrial dynamics and respiration. However, less is known about the impact of cannabidiol (CBD) on trophoblast differentiation. Due to the central role of mitochondria in stem cell differentiation, we evaluated the impact of CBD on trophoblast mitochondrial function and differentiation. Using BeWo b30 cells, we observed decreased levels of mRNA for markers of syncytialization (GCM1, ERVW1, hCG) following 20 µM CBD treatment during differentiation. In CTs, CBD elevated transcript levels for the mitochondrial and cellular stress markers HSP60 and HSP70, respectively. Furthermore, CBD treatment also increased the lipid peroxidation and oxidative damage marker 4-hydroxynonenal. Mitochondrial membrane potential, basal respiration and ATP production were diminished with the 20 µM CBD treatment in both sub-lineages. mRNA levels for endocannabinoid system (ECS) components (FAAH, NAPEPLD, TRPV1, CB1, CB2, PPARγ) were altered differentially by CBD in CTs and STs. Overall, we demonstrate that CBD impairs trophoblast differentiation and fusion, as well as mitochondrial bioenergetics and redox homeostasis.

Cannabidiol - Help and hype in targeting mucosal diseases

Cannabidiol (CBD) is one of the most commonly utilised phytocannabinoids due to its non-psychoactive and multiple potential therapeutic properties and its non-selective pharmacology. Recent studies have demonstrated efficacy of CBD in some types of drug resistant epilepsies in combination with other therapies; comparative efficacy to other agents or placebo has been hoped for anxiety, chronic pain, and inflammatory disorders based on animal data. Although CBD products are generally treated as a restricted substance, these are being eased, partially in response to significant growth in CBD product usage and increased production but more due to emerging evidence about its safety and pharmacological properties. Currently, only one CBD product (Epidiolex®) has been approved by the Australian Therapeutic Goods Administration and US Food and Drug Administration. CBD has demonstrated promise in alleviating gut and lung diseases in vitro; however, its physicochemical properties pose a significant barrier to achieving pharmacological effects in in vivo and clinical trials. Improving CBD formulations and delivery methods using technologies including self-emulsifying emulsion, nano and micro particles could overcome these shortfalls and improve its efficacy. This review focuses on the therapeutic potential of CBD in gastrointestinal and lung diseases from the available in vitro, in vivo, and clinical research. We report on identified research gaps and obstacles in the development of CBD-based therapeutics, including novel delivery methods.

Cannabidiol attenuates inflammatory impairment of intestinal cells expanding biomaterial-based therapeutic approaches

Cannabis-based biomaterials have the potential to deliver anti-inflammatory therapeutics specifically to desired cells, tissues, and organs, enhancing drug delivery and the effectiveness of anti-inflammatory treatment while minimizing toxicity. As a major component of Cannabis, Cannabidiol (CBD) has gained major attention in recent years because of its potential therapeutic properties, e.g., for restoring a disturbed barrier resulting from inflammatory conditions. The aim of this study was to test the hypothesis that CBD has beneficial effects under normal and inflammatory conditions in the established non-transformed intestinal epithelial cell model IPEC-J2. CBD induced a significant increase in transepithelial electrical resistance (TER) values and a decrease in the paracellular permeability of [³H]-D-Mannitol, indicating a strengthening effect on the barrier. Under inflammatory conditions induced by tumor necrosis factor alpha (TNFα), CBD stabilized the TER and mitigated the increase in paracellular permeability. Additionally, CBD prevented the barrier-disrupting effects of TNFα on the distribution and localization of sealing TJ proteins. CBD also affected the expression of TNF receptors. These findings demonstrate the potential of CBD as a component of Cannabis-based biomaterials used in the development of novel therapeutic approaches against inflammatory pathogenesis.

Targeting Nrf2 Signaling Pathway in Cancer Prevention and Treatment: The Role of Cannabis Compounds

The development and progression of cancer are associated with the dysregulation of multiple pathways involved in cell proliferation and survival, as well as dysfunction in redox balance, immune response, and inflammation. The master antioxidant pathway, known as the nuclear factor erythroid 2-related factor 2 (Nrf2) pathway, regulates the cellular defense against oxidative stress and inflammation, making it a promising cancer prevention and treatment target. Cannabinoids have demonstrated anti-tumor and anti-inflammatory properties, affecting signaling pathways, including Nrf2. Increased oxidative stress following exposure to anti-cancer therapy prompts cancer cells to activate antioxidant mechanisms. This indicates the dual effect of Nrf2 in cancer cells-influencing proliferation and apoptotic processes and protecting against the toxicity of anti-cancer therapy. Therefore, understanding the complex role of cannabinoids in modulating Nrf2 might shed light on its potential implementation as an anti-cancer support. In this review, we aim to highlight the impact of cannabinoids on Nrf2-related factors, with a focus on cancer prevention and treatment. Additionally, we have presented the results of several research studies that combined cannabidiol (CBD) with other compounds targeting Nrf2. Further studies should be directed toward exploring the anti-inflammatory effects of cannabinoids in the context of cancer prevention and therapy.

Proteome-Wide Profiling Using Sample Multiplexing of a Human Cell Line Treated with Cannabidiol (CBD) and Tetrahydrocannabinol (THC)

Cannabis has been used historically for both medicinal and recreational purposes, with the most notable cannabinoids being cannabidiol (CBD) and tetrahydrocannabinol (THC). Although their therapeutic effects have been well studied and their recreational use is highly debated, the underlying mechanisms of their biological effects remain poorly defined. In this study, we use isobaric tag-based sample multiplexed proteome profiling to investigate protein abundance differences in the human neuroblastoma SH-SY5Y cell line treated with CBD and THC. We identified significantly regulated proteins by each treatment and performed a pathway classification and associated protein-protein interaction analysis. Our findings suggest that these treatments may lead to mitochondrial dysfunction and induce endoplasmic reticulum stress. These data can potentially be interrogated further to investigate the potential role of CBD and THC in various biological and disease contexts, providing a foundation for future studies.

Exploring potential anti-inflammatory effects of medicinal cannabis

PURPOSE

Inflammation is thought to play a key role in malignant disease and may play a significant part in the expression of cancer-related symptoms. Cannabidiol (CBD) is a bioactive compound in cannabis and is reported to have significant anti-inflammatory properties.

METHOD

Serial C-reactive protein (CRP) levels were measured in all participants recruited to a randomised controlled trial of CBD versus placebo in patients with symptoms related to advanced cancer. A panel of inflammatory cytokines was measured over time in a subset of these patients.

RESULTS

There was no difference between the two arms in the trajectory of CRP or cytokine levels from baseline to day 28.

CONCLUSION

We were unable to demonstrate an anti-inflammatory effect of CBD in cancer patients.

TRIAL REGISTRATION

ANZCTR 26180001220257, registered 20/07/2018.

Exosomal delivery of cannabinoids against cancer

Exosomes are extracellular vesicles (EVs) originating from endosomes that play a role in cellular communication. These vesicles which mimic the parental cells that release them are promising candidates for targeted drug delivery and therapeutic applications against cancer because of their favorable biocompatibility, specific targeting, low toxicity, and immunogenicity. Currently, Delta-9-tetrahydrocannabinol (THC), cannabidiol (CBD) and other cannabinoids (e.g., CBG, THCV, CBC), are being explored for their anticancer and anti-proliferative properties. Several mechanisms, including cell cycle arrest, proliferation inhibition, activation of autophagy and apoptosis, inhibition of adhesion, metastasis, and angiogenesis have been proposed for their anticancer activity. EVs could be engineered as cannabinoid delivery systems for tumor-specificity leading to superior anticancer effects. This review discusses current techniques for EV isolation from various sources, characterization and strategies to load them with cannabinoids. More extensively, we culminate information available on different sources of EVs that have anticancer activity, mechanism of action of cannabinoids against various wild type and resistant tumors and role of CBD in histone modifications and cancer epigenetics. We have also enumerated the role of EVs containing cannabinoids against various tumors and in chemotherapy induced neuropathic pain.

Antitumor mechanism of cannabidiol hidden behind cancer hallmarks

Cannabinoids have been utilized for recreational and therapeutic purposes for over 4,000 years. As the primary ingredient in exogenous cannabinoids, Cannabidiol (CBD) has drawn a lot of interest from researchers due to its negligible psychotropic side effects and potential tumor-suppressing properties. However, the obscure mechanisms that underlie them remain a mystery. Complex biological mechanisms are involved in the progression of cancer, and malignancies have a variety of acquired biological capabilities, including sustained proliferation, death evasion, neovascularization, tissue invasion and metastasis, immune escape, metabolic reprogramming, induction of tumor-associated inflammation, cancerous stemness and genomic instability. Nowadays, the role of CBD hidden in these hallmarks is gradually revealed. Nevertheless, flaws or inconsistencies in the recent studies addressing the anti-cancer effects of CBD still exist. The purpose of this review is to evaluate the potential mechanisms underlying the role of CBD in a range of tumor-acquired biological capabilities. We propose potential drugs that may have a synergistic effect with CBD and provide optional directions for future research.

A novel mechanism of cannabidiol in suppressing ovarian cancer through LAIR-1 mediated mitochondrial dysfunction and apoptosis

Cannabidiol (CBD) is a nonpsychoactive cannabinoid compound. It has been shown that CBD can inhibit the proliferation of ovarian cancer cells, but the underlying specific mechanism is unclear. We previously presented the first evidence for the expression of leukocyte-associated immunoglobulin-like receptor 1 (LAIR-1), a member of the immunosuppressive receptor family, in ovarian cancer cells. In the present study, we investigated the mechanism by which CBD inhibits the growth of SKOV3 and CAOV3 ovarian cancer cells, and we sought to understand the concurrent role of LAIR-1. In addition to inducing ovarian cancer cell cycle arrest and promoting cell apoptosis, CBD treatment significantly affected the expression of LAIR-1 and inhibited the PI3K/AKT/mTOR signaling axis and mitochondrial respiration in ovarian cancer cells. These changes were accompanied by an increase in ROS, loss of mitochondrial membrane potential, and suppression of mitochondrial respiration and aerobic glycolysis, thereby inducing abnormal or disturbed metabolism and reducing ATP production. A combined treatment with N-acetyl-l-cysteine and CBD indicated that a reduction in ROS production would restore PI3K/AKT/mTOR pathway signaling and ovarian cancer cell proliferation. We subsequently confirmed that the inhibitory effect of CBD on the PI3K/AKT/mTOR signal axis and mitochondrial bioenergy metabolism was attenuated by knockdown of LAIR-1. Our animal studies further support the in vivo anti-tumor activity of CBD and suggest its mechanism of action. In summary, the present findings confirm that CBD inhibits ovarian cancer cell growth by disrupting the LAIR-1-mediated interference with mitochondrial bioenergy metabolism and the PI3K/AKT/mTOR pathway. These results provide a new experimental basis for research into ovarian cancer treatment based on targeting LAIR-1 with CBD.

The endocannabinoid system, a new gatekeeper in the pharmacology of human hepatocellular carcinoma

Despite numerous prevention methodologies and treatment options, hepatocellular carcinoma (HCC) still remains as the third leading life-threatening cancer. It is thus pertinent to develop new treatment modality to fight this devastating carcinoma. Ample recent studies have shown the anti-inflammatory and antitumor roles of the endocannabinoid system in various forms of cancers. Preclinical studies have also confirmed that cannabinoid therapy can be an optimal regimen for cancer treatments. The endocannabinoid system is involved in many cancer-related processes, including induction of endoplasmic reticulum (ER) stress-dependent apoptosis, autophagy, PITRK and ERK signaling pathways, cell invasion, epithelial-mesenchymal transition (EMT), and cancer stem cell (CSC) phenotypes. Moreover, changes in signaling transduction of the endocannabinoid system can be a potential diagnostic and prognostic biomarker for HCC. Due to its pivotal role in lipid metabolism, the endocannabinoid system affects metabolic reprogramming as well as lipid content of exosomes. In addition, due to the importance of non-coding RNAs (ncRNAs), several studies have examined the relationship between microRNAs and the endocannabinoid system in HCC. However, HCC is a pathological condition with high heterogeneity, and therefore using the endocannabinoid system for treatment has faced many controversies. While some studies favored a role of the endocannabinoid system in carcinogenesis and tumor induction, others exhibited the anticancer potential of endocannabinoids in HCC. In this review, specific studies delineating the relationship between endocannabinoids and HCC are examined. Based on collected findings, detailed studies of the molecular mechanism of endocannabinoids as well as preclinical studies for investigating therapeutic or carcinogenic impacts in HCC cancer are strongly suggested.

Tetrahydrocannabivarin (THCV) Protects Adipose-Derived Mesenchymal Stem Cells (ASC) against Endoplasmic Reticulum Stress Development and Reduces Inflammation during Adipogenesis

The endoplasmic reticulum (ER) fulfills essential duties in cell physiology, and impairment of this organelle's functions is associated with a wide number of metabolic diseases. When ER stress is generated in the adipose tissue, it is observed that the metabolism and energy homeostasis of the adipocytes are altered, leading to obesity-associated metabolic disorders such as type 2 diabetes (T2D). In the present work, we aimed to evaluate the protective effects of Δ9-tetrahydrocannabivarin (THCV, a cannabinoid compound isolated from Cannabis sativa L.) against ER stress in adipose-derived mesenchymal stem cells. Our results show that pre-treatment with THCV prevents the subcellular alteration of cell components such as nuclei, F-actin, or mitochondria distribution, and restores cell migration, cell proliferation and colony-forming capacity upon ER stress. In addition, THCV partially reverts the effects that ER stress induces regarding the activation of apoptosis and the altered anti- and pro-inflammatory cytokine profile. This indicates the protective characteristics of this cannabinoid compound in the adipose tissue. Most importantly, our data demonstrate that THCV decreases the expression of genes involved in the unfolded protein response (UPR) pathway, which were upregulated upon induction of ER stress. Altogether, our study shows that the cannabinoid THCV is a promising compound that counters the harmful effects triggered by ER stress in the adipose tissue. This work paves the way for the development of new therapeutic means based on THCV and its regenerative properties to create a favorable environment for the development of healthy mature adipocyte tissue and to reduce the incidence and clinical outcome of metabolic diseases such as diabetes.

Cannabidiol and Cannabis Sativa as a potential treatment in vitro prostate cancer cells silenced with RBBp6 and PC3 xenograft

BACKGROUND

Prostate cancer is the second most frequently occurring carcinoma in males worldwide and one of the leading causes of death in men around the world. Recent studies estimate that over 1.4 million males are diagnosed with prostate cancer on an annual basis, with approximately 375,000 succumbing to the disease annually. With current treatments continuing to show severe side effects, there is a need for new treatments. In this study we looked at the effect of cannabis sativa extract, cannabidiol and cisplatin on prostate cancer cells, PC3.

METHODS

In addressing the above questions, we employed the MTT assay to measure the antiproliferative effect on PC3 cells following treatment with varying concentrations of Cannabis sativa extract, cisplatin and cannabidiol. xCELLigence was also used to confirm the IC50 activity in which cells were grown in a 16 well plate coated with gold and monitor cell attachment. Caspase 3/7 activity was also measured using 96 well-plate following treatment. Western-blot and qRT-PCR was also used to measure the gene expression of tumour suppressor genes, p53, Bax and Bcl2. Animal studies were employed to measure the growth of PC3-mouse derived cancer to evaluate the effect of compounds in vivo.

RESULTS

From the treatment with varying concentrations of Cannabis sativa extract, cannabidiol and cisplatin, we have observed that the three compounds induced antiproliferation of PC3 cancer cell lines through the activation of caspase 3/7 activity. We also observed induction of apoptosis in these cells following silencing of retinoblastoma binding protein 6 (RBBP6), with upregulation of p53 and bax mRNA expression, and a reduction in Bcl2 gene expression. The growth of tumours in the mouse models were reduced following treatment with cisplatin and cannabidiol.

CONCLUSION

We demonstrated that cannabidiol is a viable therapy to treat prostate cancer cells, in combination with silencing of RBBP6. This suggests that cannabidiol rather Cannabis sativa extract may play an important role in reducing cancer progression.

Beyond Pain Relief: A Review on Cannabidiol Potential in Medical Therapies

The phytocannabinoid cannabidiol (CBD) is receiving increasing attention due to its pharmacological properties. Although CBD is extracted from Cannabis sativa, it lacks the psychoactive effects of Δ9-tetrahydrocannabinol (THC) and has become an attractive compound for pharmacological uses due to its anti-inflammatory, antioxidant, anticonvulsant, and anxiolytic potential. The molecular mechanisms involved in CBD's biological effects are not limited to its interaction with classical cannabinoid receptors, exerting anti-inflammatory or pain-relief effects. Several pieces of evidence demonstrate that CBD interacts with other receptors and cellular signaling cascades, which further support CBD's therapeutic potential beyond pain management. In this review, we take a closer look at the molecular mechanisms of CBD and its potential therapeutic application in the context of cancer, neurodegeneration, and autoimmune diseases.

A nanoformulation for immunosuppression reversal and broad-spectrum self-amplifying antitumor ferroptosis-immunotherapy

The efficacy of immunotherapy combined with other therapeutic modalities in the management of cancer has been extensively studied. However, no effective strategy to improve the antitumor effects of immunotherapy at the tumor site has been developed. In this study, we describe a nanoformulation (CP) that integrates ferroptosis-inducing cannabinoid nanoparticles with immunostimulatory Poly(I:C) to enhance antitumor immune responses by activating ferroptosis-immunotherapy pathways. The results indicated that CP nanoformulation effectively induced ferroptosis, cellular immunogenic death, and anti-tumor immune responses which initiate T cell responses leading to the inhibition of established tumors. In addition, CP nanoformulations reversed the tumor immunosuppressive microenvironment and promoted tumor ferroptosis. These results indicated that the self-amplifying nanoformulation may be an effective strategy for broad-spectrum cancer immunotherapy.

Cannabinoid-mediated targeting of mitochondria on the modulation of mitochondrial function and dynamics

Mitochondria play a critical role in the regulation of several biological processes (e.g., programmed cell death, inflammation, neurotransmission, cell differentiation). In recent years, accumulating findings have evidenced that cannabinoids, a group of endogenous and exogenous (synthetic and plant-derived) psychoactive compounds that bind to cannabinoid receptors, may modulate mitochondrial function and dynamics. As such, mitochondria have gained increasing interest as central mediators in cannabinoids' pharmacological and toxicological signatures. Here, we review the mechanisms underlying the cannabinoids' modulation of mitochondrial activity and dynamics, as well as the potential implications of such mitochondrial processes' disruption on cell homeostasis and disease. Interestingly, cannabinoids may target different mitochondrial processes (e.g., regulation of intracellular calcium levels, bioenergetic metabolism, apoptosis, and mitochondrial dynamics, including mitochondrial fission and fusion, transport, mitophagy, and biogenesis), by modulating multiple and complex signaling pathways. Of note, the outcome may depend on the experimental models used, as well as the chemical structure, concentration, and exposure settings to the cannabinoid, originating equivocal data. Notably, this interaction seems to represent not only an important feature of cannabinoids' toxicological signatures, with potential implications for the onset of distinct pathological conditions (e.g., cancer, neurodegenerative diseases, metabolic syndromes), but also an opportunity to develop novel therapeutic strategies for such pathologies, which is also discussed in this review.

Role of Cannabidiol for Improvement of the Quality of Life in Cancer Patients: Potential and Challenges

There is currently a growing interest in the use of cannabidiol (CBD) to alleviate the symptoms caused by cancer, including pain, sleep disruption, and anxiety. CBD is often self-administered as an over-the-counter supplement, and patients have reported benefits from its use. However, despite the progress made, the mechanisms underlying CBD’s anti-cancer activity remain divergent and unclear. Herein, we provide a comprehensive review of molecular mechanisms to determine convergent anti-cancer actions of CBD from pre-clinical and clinical studies. In vitro studies have begun to elucidate the molecular targets of CBD and provide evidence of CBD’s anti-tumor properties in cell and mouse models of cancer. Furthermore, several clinical trials have been completed testing CBD’s efficacy in treating cancer-related pain. However, most use a mixture of CBD and the psychoactive, tetrahydrocannabinol (THC), and/or use variable dosing that is not consistent between individual patients. Despite these limitations, significant reductions in pain and opioid use have been reported in cancer patients using CBD or CBD+THC. Additionally, significant improvements in quality-of-life measures and patients’ overall satisfaction with their treatment have been reported. Thus, there is growing evidence suggesting that CBD might be useful to improve the overall quality of life of cancer patients by both alleviating cancer symptoms and by synergizing with cancer therapies to improve their efficacy. However, many questions remain unanswered regarding the use of CBD in cancer treatment, including the optimal dose, effective combinations with other drugs, and which biomarkers/clinical presentation of symptoms may guide its use.

Cannabidiol (CBD) Protects Adipose-Derived Mesenchymal Stem Cells (ASCs) against Endoplasmic Reticulum Stress Development and Its Complications

BACKGROUND

Recent studies suggested that individuals with metabolic disorders have altered function of adipocytes and adipose stem cell subpopulations, which impairs tissue homeostasis, promoting insulin resistance and diabetes development. The non-psychoactive phytocannabinoid CBD was found to modulate adipose tissue metabolism, however, its exact role in controlling ASCs' fate is still poorly understood.

OBJECTIVES

This investigation aimed to elucidate whether pretreatment of ASCs with CBD can protect against ER stress development and maintain the cytophysiological properties of cells.

METHODS

Human ASCs were cultured under control and adipogenic conditions. Prior to the experiments, cells in the experimental group were pretreated with CBD following the addition of an ER stress inducer-tunicamycin. After the experiments, the cells were subsequently tested for expression of the apoptotic, ER stress, and anti-inflammatory-related genes using RT-qPCR. Oxidative stress was analysed with flow cytometric assays.

RESULTS

Cells pretreated with CBD displayed decreased apoptosis and enhanced proliferation rate. Additionally, the expression of pro-inflammatory cytokines and miRNAs was significantly reduced. The obtained results also demonstrated an obvious reduction in intracellular accumulated ROS and NO, as well as mitigated ER stress through the down-regulation of IRE-1, PERK, CHOP, and ATF6 transcripts upon CBD treatment.

CONCLUSION

The presented data provide the evidence that CBD protects ASCs against ER stress development and its complications and, thus, offers new insights for the management of obesity through the regulation of adipose tissue dynamics.

Controversial Link between Cannabis and Anticancer Treatments-Where Are We and Where Are We Going? A Systematic Review of the Literature

Simple Summary

In the field of oncology, preclinical research has shown that cannabis and cannabinoids modulate signaling pathways involved in cell proliferation, migration, invasion, angiogenesis, programmed cell death, and metastasis. Based on these findings, as medical cannabis becomes legal in more and more countries, cancer patients and their families are increasingly interested in the potential benefits of herbal medicine as an element of complementary and alternative medicine in their treatment. Although its clinical efficacy has been demonstrated in preclinical studies, clinical trials with cancer patients are lacking. To draw clear conclusions, we await the results of further prospective and randomized studies on this clinically relevant topic.

Abstract

Background and Objectives: Cannabinoids are currently used in cancer patients primarily for their pain-relieving and antiemetic properties. The aim of our review was to synthesize all available data of studies evaluating the therapeutic efficacy of cannabis in combination with oncological treatments in cancer patients and to explore ongoing studies with different goals and medical areas registered in the field of oncology worldwide. Materials and Methods: This study was performed in accordance with the PRISMA guidelines. A search using MEDLINE/PubMed database was performed between 1 January 2006 and 1 March 2022. Search terms included the following: cannabidiol, cannabis, CBD, dronabinol, endocannabinoids, medical marijuana, nabiximols, nabilone, THC, and cancer. All studies that examined the efficacy of cannabis administered during oncological treatments, regardless of cancer localization, subtype, and sample size, were considered eligible. Results: In three studies, cannabis was administered to patients with glioblastoma, and in two other studies, cannabis was used in combination with immunotherapy in various cancer subgroups. The results of the clinical trials in cancer patients are not sufficient to draw conclusions at this time. Interestingly, several other studies addressing the systemic effects of cannabinoids in cancer patients are currently listed in the U.S. National Library of Medicine’s registry on the ClinicalTrials.gov website. However, only one of the registered studies examined the efficacy of cannabinoids as a potential option for systemic cancer treatment. Conclusions: Although cannabis is touted to the public as a cancer cure, clinical trials need to clarify which combinations of chemotherapeutic agents with cannabinoids are useful for cancer patients.

Cannabidiol inhibits invasion and metastasis in colorectal cancer cells by reversing epithelial-mesenchymal transition through the Wnt/β-catenin signaling pathway

Colorectal cancer (CRC) is the leading cause of cancer deaths worldwide, wherein distant metastasis is the main reason for death. The non-psychoactive phytocannabinoid cannabidiol (CBD) effectively induces the apoptosis of CRC cells. We investigated the role of CBD in the migration and metastasis of CRC cells. CBD significantly inhibited proliferation, migration, and invasion of colon cancer cells in a dose- or time-dependent manner. CBD could also inhibit epithelial-mesenchymal transition (EMT) by upregulating epithelial markers such as E-cadherin and downregulating mesenchymal markers such as N-cadherin, Snail, Vimentin, and HIF-1α. CBD could suppress the activation of the Wnt/β-catenin signaling pathway, inhibit the expression of β-catenin target genes such as APC and CK1, and increase the expression of Axin1. Compared to the control group, the volume and weight of orthotopic xenograft tumors significantly decreased after the CBD treatment. The results demonstrated that CBD inhibits invasion and metastasis in CRC cells. This was the first study elucidating the underlying molecular mechanism of CBD in inhibiting EMT and metastasis via the Wnt/β-catenin signaling pathway in CRC cells. The molecular mechanism by which CBD inhibits EMT and metastasis of CRC cells was shown to be through the Wnt/β-catenin signaling pathway for the first time.

Cannabidiol Regulates PPARγ-Dependent Vesicle Formation as well as Cell Death in A549 Human Lung Cancer Cells

Extracts of phytocannabinoids from Cannabis sativa have been studied for therapeutic purposes. Although nonpsychoactive CBD has been studied as a promising anticancer drug because it induces apoptosis in many cancer cells, it is also known to induce several physiological changes. In this study, we clarify the functional role it plays in the morphological characteristics of intracellular vesicle formation as well as apoptosis in A549 human lung cancer cells. CBD treatment shows growth inhibition at concentrations above 20 μM, but FACS analysis shows low efficacy in terms of cell death. Microscopic observations suggest that multiple vesicles were detected in the cytoplasmic region of CBD-treated A549 cells. CBD treatment upregulates apoptosis-related proteins, such as p53, PARP, RIP1, RIP3, Atg12, and Beclin, indicating that CBD regulates several types of cell death. CBD treatment also induced E-cadherin, PPARγ, clathrin, β-adaptin, and Tsg101, also known to be cellular-differentiation inducers or vesicle-formation components. Treatment combining CBD with GW9662, a PPARγ inhibitor, reduced CBD-induced cytoplasmic vesicle formation. This indicates that PPARγ regulates the vesicle-formation mechanism. However, CBD-treated E-cad KO clones did not show this regulatory mechanism. These results elucidate the pharmacological and molecular networks associated with CBD in PPARγ-dependent vesicle formation and the induction of apoptosis.

The Combination of Δ9-Tetrahydrocannabinol and Cannabidiol Suppresses Mitochondrial Respiration of Human Glioblastoma Cells via Downregulation of Specific Respiratory Chain Proteins

Simple Summary

Cannabidiol (CBD) is a phytocannabinoid from Cannabis sativa L. that exhibits no psychoactivity and, like the psychoactive cannabinoid Δ⁹-tetrahydrocannabinol (THC), shows anticancer effects in preclinical cell and animal models. Previous studies have indicated a stronger cancer-targeting effect when THC and CBD are combined. Here, we investigated how the combination of THC and CBD in a 1:1 ratio affects glioblastoma cell survival. The compounds were found to synergistically enhance cell death, which was attributed to mitochondrial damage and disruption of energy metabolism. A detailed look at the mitochondrial electron transfer chain showed that THC/CBD selectively decreased certain subunits of complexes I and IV. These data highlight the fundamental changes in cellular energy metabolism when cancer cells are exposed to a mixture of cannabinoids and underscore the potential of combining cannabinoids in cancer treatment.

Abstract

Phytocannabinoids represent a promising approach in glioblastoma therapy. Previous work has shown that a combined treatment of glioblastoma cells with submaximal effective concentrations of psychoactive Δ⁹-tetrahydrocannabinol (THC) and non-psychoactive cannabidiol (CBD) greatly increases cell death. In the present work, the glioblastoma cell lines U251MG and U138MG were used to investigate whether the combination of THC and CBD in a 1:1 ratio is associated with a disruption of cellular energy metabolism, and whether this is caused by affecting mitochondrial respiration. Here, the combined administration of THC and CBD (2.5 µM each) led to an inhibition of oxygen consumption rate and energy metabolism. These effects were accompanied by morphological changes to the mitochondria, a release of mitochondrial cytochrome c into the cytosol and a marked reduction in subunits of electron transport chain complexes I (NDUFA9, NDUFB8) and IV (COX2, COX4). Experiments with receptor antagonists and inhibitors showed that the degradation of NDUFA9 occurred independently of the activation of the cannabinoid receptors CB₁, CB₂ and TRPV1 and of usual degradation processes mediated via autophagy or the proteasomal system. In summary, the results describe a previously unknown mitochondria-targeting mechanism behind the toxic effect of THC and CBD on glioblastoma cells that should be considered in future cancer therapy, especially in combination strategies with other chemotherapeutics.

Down-regulated HSA_circ_0003528 inhibits hepatocellular carcinoma aggressiveness via the miR-212-3p/XIAP axis

Hepatocellular carcinoma (HCC) is characterized by a high mortality rate. Dysregulated circular RNAs (circRNAs) play a vital role in HCC. We aimed to study the role of circ_0003528 in HCC and its fundamental molecular mechanisms. HSA_circ_0003528 was identified through bioinformatics dataset analysis. The binding sites between mRNA and miRNA were predicted using online bioinformatics tools. The interaction between miR-212-3p and X-linked inhibitor of apoptosis protein (XIAP) or circ_0003528 was confirmed through the luciferase reporter assay. RT-qPCR and western blot assays were used to analyze the expression of all miRNAs/mRNAs and proteins. Cellular functions were evaluated using the MTT and TUNEL assays. A xenograft model was established to evaluate the function of circ_0003528 in vivo. Circ_0003528 was dramatically overexpressed in HepG2 and HUH7 cells. However, knockdown of circ_0003528 suppressed the aggressiveness of HCC cells and tumor growth both in vitro and in vivo. Furthermore, binding of miR-212-3p to circ_0003528 and XIAP was verified. Downregulation of miR-212-3p abrogated the effects of si-circ_0003528 on cell viability and apoptosis, and upregulation of XIAP antagonized the functions of the miR-212-3p mimic in HCC cells. circ_0003528 contributes to the development of HCC in vitro and in vivo via the miR-212-3p/XIAP axis. Hence, circ_0003528 knockdown may be a potential therapeutic strategy for HCC treatment.

Cannabidiol on the Path from the Lab to the Cancer Patient: Opportunities and Challenges

Cannabidiol (CBD), a major non-psychotropic component of cannabis, is receiving growing attention as a potential anticancer agent. CBD suppresses the development of cancer in both in vitro (cancer cell culture) and in vivo (xenografts in immunodeficient mice) models. For critical evaluation of the advances of CBD on its path from laboratory research to practical application, in this review, we wish to call the attention of scientists and clinicians to the following issues: (a) the biological effects of CBD in cancer and healthy cells; (b) the anticancer effects of CBD in animal models and clinical case reports; (c) CBD's interaction with conventional anticancer drugs; (d) CBD's potential in palliative care for cancer patients; (e) CBD's tolerability and reported side effects; (f) CBD delivery for anticancer treatment.

Anti-Microbial Activity of Phytocannabinoids and Endocannabinoids in the Light of Their Physiological and Pathophysiological Roles

Antibiotic resistance has become an increasing challenge in the treatment of various infectious diseases, especially those associated with biofilm formation on biotic and abiotic materials. There is an urgent need for new treatment protocols that can also target biofilm-embedded bacteria. Many secondary metabolites of plants possess anti-bacterial activities, and especially the phytocannabinoids of the Cannabis sativa L. varieties have reached a renaissance and attracted much attention for their anti-microbial and anti-biofilm activities at concentrations below the cytotoxic threshold on normal mammalian cells. Accordingly, many synthetic cannabinoids have been designed with the intention to increase the specificity and selectivity of the compounds. The structurally unrelated endocannabinoids have also been found to have anti-microbial and anti-biofilm activities. Recent data suggest for a mutual communication between the endocannabinoid system and the gut microbiota. The present review focuses on the anti-microbial activities of phytocannabinoids and endocannabinoids integrated with some selected issues of their many physiological and pharmacological activities.

PSMC2 knockdown inhibits the progression of oral squamous cell carcinoma by promoting apoptosis via PI3K/Akt pathway

Proteasome 26S subunit, ATPase 2 (PSMC2) is a recently identified gene which is potentially associated with human carcinogenesis. However, the effects of PSMC2 on oral squamous cell carcinoma (OSCC) is still unclear. Here, we investigated PSMC2 expression in OSCC tissues and explored its effects on the biological behaviors of OSCC cells. PSMC2 expression was evaluated by immunohistochemistry in a tissue microarray containing 60 OSCC tissues and 9 normal tissues. PSMC2 was knocked down through lentivirus infection in OSCC cell lines. MTT, colony formation, flow cytometry, transwell, and scratch assays were performed to detect effects of PSMC2 knockdown on phenotypes of OSCC cells. Human apoptosis antibody array was used to screen potential downstream of PSMC2 in OSCC. Finally, the effects of PSMC2 knockdown on tumor growth were assessed in a tumor xenograft model using BALB/c nude mice. PSMC2 expression was significantly upregulated in OSCC tissues compared with normal tissues and correlated with poor prognosis. PSMC2 knockdown significantly suppressed cell proliferation, migration, but promoted apoptosis of OSCC cells. Additionally, we confirmed that PSMC2 knockdown can increase the expression of pro-apoptotic proteins. Furthermore, we found that PSMC2 knockdown downregulated expression of p100, p-Akt, CDK6, and upregulated of MAPK9. Xenograft experiments revealed that PSMC2 knockdown can suppress OSCC tumor growth and promote apoptosis. This study demonstrated that PSMC2 plays a critical role in OSCC progression through affecting pro-apoptotic protein expression and apoptosis pathways. It indicated that targeting PSMC2 might be a promising strategy for OSCC treatment.

Cannabidiol Induces Cell Death in Human Lung Cancer Cells and Cancer Stem Cells

Currently, there is no effective therapy against lung cancer due to the development of resistance. Resistance contributes to disease progression, recurrence, and mortality. The presence of so-called cancer stem cells could explain the ineffectiveness of conventional treatment, and the development of successful cancer treatment depends on the targeting also of cancer stem cells. Cannabidiol (CBD) is a cannabinoid with anti-tumor properties. However, the effects on cancer stem cells are not well understood. The effects of CBD were evaluated in spheres enriched in lung cancer stem cells and adherent lung cancer cells. We found that CBD decreased viability and induced cell death in both cell populations. Furthermore, we found that CBD activated the effector caspases 3/7, increased the expression of pro-apoptotic proteins, increased the levels of reactive oxygen species, as well as a leading to a loss of mitochondrial membrane potential in both populations. We also found that CBD decreased self-renewal, a hallmark of cancer stem cells. Overall, our results suggest that CBD is effective against the otherwise treatment-resistant cancer stem cells and joins a growing list of compounds effective against cancer stem cells. The effects and mechanisms of CBD in cancer stem cells should be further explored to find their Achilles heel.

Cannabidiol Decreases Metalloproteinase Activity and Normalizes Angiogenesis Factor Expression in UVB-Irradiated Keratinocytes from Psoriatic Patients

The development of psoriasis is associated with the consequences of oxidative stress and inflammation leading to metabolic changes locally, in the skin cells, and systemically, in the blood. Therefore, the aim of this study was to analyze the effect of psoriasis vulgaris (PsV) and psoriatic arthritis (PsA) on the basal plasma/keratinocyte levels of matrix metalloproteinases (MMPs), tissue inhibitors of matrix metalloproteinases (TIMPs), and angiogenesis factors, as well as to evaluate the effect of CBD on these parameters in keratinocytes isolated from psoriatic/healthy individuals with and without in vitro irradiation by UVB. A quantitative chemiluminescent method of detection based on an ELISA protocol and zymography technique was used during analysis. It was shown that activity levels of MMP-9 and TIMP-2 in PsA plasma were higher than in PsV. Changes in the proteolytic activity were accompanied by an increase in markers of angiogenesis (angiopoietin-2, HGF, VEGF, TNFα, PDGF, FGF), where in the specific case of angiopoietin-2 and TNFα, the overexpression in PsV was significantly stronger than in PsA. CBD application to keratinocytes partially restored levels of MMP-1/2/3/7 and TIMP-1/2 (in an effect which was particularly enhanced by UVB irradiation), as well as levels of the examined angiogenic factors except TNFα (levels of which were increased in psoriatic keratinocytes and decreased in healthy keratinocytes). Presented results indicate that CBD may be suggested as an antiangiogenic factor that reduces the proinflammatory action of UVB in psoriatic keratinocytes and partially has a protective effect for healthy keratinocytes.

Synergistic Interactions of Cannabidiol with Chemotherapeutic Drugs in MCF7 Cells: Mode of Interaction and Proteomics Analysis of Mechanisms

Cannabidiol (CBD), a nonpsychoactive phytocannabinoid, has recently emerged as a potential cytotoxic agent in addition to its ameliorative activity in chemotherapy-associated side effects. In this work, the potential interactions of CBD with docetaxel (DOC), doxorubicin (DOX), paclitaxel (PTX), vinorelbine (VIN), and 7-ethyl-10-hydroxycamptothecin (SN-38) were explored in MCF7 breast adenocarcinoma cells using different synergy quantification models. The apoptotic profiles of MCF7 cells after the treatments were assessed via flow cytometry. The molecular mechanisms of CBD and the most promising combinations were investigated via label-free quantification proteomics. A strong synergy was observed across all synergy models at different molar ratios of CBD in combination with SN-38 and VIN. Intriguingly, synergy was observed for CBD with all chemotherapeutic drugs at a molar ratio of 636:1 in almost all synergy models. However, discording synergy trends warranted the validation of the selected combinations against different models. Enhanced apoptosis was observed for all synergistic CBD combinations compared to monotherapies or negative controls. A shotgun proteomics study highlighted 121 dysregulated proteins in CBD-treated MCF7 cells compared to the negative controls. We reported the inhibition of topoisomerase II β and α, cullin 1, V-type proton ATPase, and CDK-6 in CBD-treated MCF7 cells for the first time as additional cytotoxic mechanisms of CBD, alongside sabotaged energy production and reduced mitochondrial translation. We observed 91 significantly dysregulated proteins in MCF7 cells treated with the synergistic combination of CBD with SN-38 (CSN-38), compared to the monotherapies. Regulation of telomerase, cell cycle, topoisomerase I, EGFR1, protein metabolism, TP53 regulation of DNA repair, death receptor signalling, and RHO GTPase signalling pathways contributed to the proteome-wide synergistic molecular mechanisms of CSN-38. In conclusion, we identified significant synergistic interactions between CBD and the five important chemotherapeutic drugs and the key molecular pathways of CBD and its synergistic combination with SN-38 in MCF7 cells. Further in vivo and clinical studies are warranted to evaluate the implementation of CBD-based synergistic adjuvant therapies for breast cancer.

Cannabidiol Effectively Promoted Cell Death in Bladder Cancer and the Improved Intravesical Adhesion Drugs Delivery Strategy Could Be Better Used for Treatment

Cannabidiol (CBD), a primary bioactive phytocannabinoid extracted from hemp, is reported to possess potent anti-tumorigenic activity in multiple cancers. However, the effects of CBD on bladder cancer (BC) and the underlying molecular mechanisms are rarely reported. Here, several experiments proved that CBD promoted BC cells (T24, 5637, and UM-UC-3) death. For example, T24 cells were treated with 12 µM CBD for 48 h, flow cytometry analysis demonstrated that early and late apoptotic cells were accounted for by 49.91%, indicating CBD enhanced cell apoptosis ability. To deeper explore molecular mechanisms, the CBD-treated T24 cell transcriptome libraries were established. KEGG analysis implied that the significantly changed genes were enriched in the PI3K/Akt pathway. qRT-PCR and Western blot assays verified that CBD regulated BC cells growth and migration and induced apoptosis by inactivating the PI3K/Akt pathway. Meanwhile, the developed chitosan to wrap CBD-loaded PLGA nanoparticles can significantly enhance the adhesion of the material to the mouse bladder wall, and the binding efficiency of mucin to chitosan-PLGA nanoparticles reached 97.04% ± 1.90%. In summary, this work demonstrates that CBD may become a novel reliable anticancer drug and the developed intravesical adhesion system is expected to turn into a potential means of BC chemotherapy drug delivery.

Cannabidiol Induces Apoptosis and Perturbs Mitochondrial Function in Human and Canine Glioma Cells

Cannabidiol (CBD), the major non-psychoactive compound found in cannabis, is frequently used both as a nutraceutical and therapeutic. Despite anecdotal evidence as an anticancer agent, little is known about the effect CBD has on cancer cells. Given the intractability and poor prognoses of brain cancers in human and veterinary medicine, we sought to characterize the in vitro cytotoxicity of CBD on human and canine gliomas. Glioma cells treated with CBD showed a range of cytotoxicity from 4.9 to 8.2 μg/ml; canine cells appeared to be more sensitive than human. Treatment with >5 μg/ml CBD invariably produced large cytosolic vesicles. The mode of cell death was then interrogated using pharmacologic inhibitors. Inhibition of apoptosis was sufficient to rescue CBD-mediated cytotoxicity. Inhibition of RIPK3, a classical necroptosis kinase, also rescued cells from death and prevented the formation of the large cytosolic vesicles. Next, cellular mitochondrial activity in the presence of CBD was assessed and within 2 hours of treatment CBD reduced oxygen consumption in a dose dependent manner with almost complete ablation of activity at 10 μg/ml CBD. Fluorescent imaging with a mitochondrial-specific dye revealed that the large cytosolic vesicles were, in fact, swollen mitochondria. Lastly, calcium channels were pharmacologically inhibited and the effect on cell death was determined. Inhibition of mitochondrial channel VDAC1, but not the TRPV1 channel, rescued cells from CBD-mediated cytotoxicity. These results demonstrate the cytotoxic nature of CBD in human and canine glioma cells and suggest a mechanism of action involving dysregulation of calcium homeostasis and mitochondrial activity.

Circ_0006174 promotes colorectal cancer progression by sponging microRNA-142-3p and regulating X-linked inhibitor of apoptosis expression

BACKGROUND

Circular RNAs (circRNAs) are crucial in the regulation of gene expression and biological processes. However, in colorectal cancer, the expression characteristics and biological function of circRNA_0006174 (circ_0006174) is not fully understood. This work is aimed to investigate the biological function of circ_0006174 in colorectal cancer and its molecular mechanism.

METHODS

Circ_0006174, microRNA-142-3p and X-linked inhibitor of apoptosis expression levels were detected in colorectal cancer tissues and cells using quantitative real-time polymerase chain reaction analysis or Western blot. The effects of circ_0006174 on colorectal cancer cell proliferation, apoptosis, migration and invasion were detected using the cell counting kit-8 method, bromodeoxyuridine experiments, flow cytometry analysis and Transwell experiments. The targeting relationship among circ_0006174, microRNA-142-3p and X-linked inhibitor of apoptosis was analysed by bioinformatics prediction, dual-luciferase reporter experiment and RNA immunoprecipitation experiment.

RESULTS

Circ_0006174 was up-regulated in colorectal cancer tissues as well as in cell lines, and its high expression was remarkably associated with enlarged tumour volume and advanced tumour, node, metastasis stage of the patients. Circ_0006174 overexpression enhanced colorectal cancer cell proliferation, migration and invasion, and inhibited colorectal cancer cell apoptosis; while knocking down circ_0006174 caused the opposite effects. Circ_0006174 directly targeted and negatively regulated microRNA-142-3p expression, and X-linked inhibitor of apoptosis, a target gene of microRNA-142-3p, could be indirectly and positively modulated by circ_0006174.

CONCLUSION

Circ_0006174 facilitates colorectal cancer cell proliferation, migration and invasion, and represses colorectal cancer cell apoptosis by regulating microRNA-142-3p/X-linked inhibitor of apoptosis axis.

Design and synthesis of novel mitochondria-targeted CDDO derivatives as potential anti-cancer agents

A large number of derivatives of natural pentacyclic triterpenoid oleanolic acid (OA) with various activities have been reported, including CDDO derivatives (CDDOs). CDDOs show potent antitumor activity, but they lack selectivity for tumor cells which causes serious side effects. In this study, based on the truth that tumor cells display higher mitochondrial membrane potential, to improve their mitochondrial-targeting ability, triphenylphosphine cations (TPP⁺) or tricyclohexylphosphine cations (TCP⁺) were linked to CDDO. Among these compounds, the TPP⁺ derivative 5b exhibited greater activity against the tumor cells than CDDO-Me, and the selectivity for the tumor cells was obviously improved. Further investigation revealed that the uptake of 5b in the mitochondria of MCF-7 cells was increased compared to CDDO-Me. In addition, 5b was able to cause mitochondrial membrane potential decline and cell cycle arrest. Furthermore, 5b caused apoptosis mainly through the mitochondria-mediated intrinsic pathway. Taken together, our study provides a possible solution to the poor selectivity of CDDOs, and regains confidence in the treatment of tumor with CDDOs.

A Novel Mechanism of Cannabidiol in Suppressing Hepatocellular Carcinoma by Inducing GSDME Dependent Pyroptosis

Cannabidiol (CBD), a phytochemical derived from Cannabis sativa L., has been demonstrated to exhibit promising anti-tumor properties in multiple cancer types. However, the effects of CBD on hepatocellular carcinoma (HCC) cells remain unknown. We have shown that CBD effectively suppresses HCC cell growth in vivo and in vitro, and induced HCC cell pyroptosis in a caspase-3/GSDME-dependent manner. We further demonstrated that accumulation of integrative stress response (ISR) and mitochondrial stress may contribute to the initiation of pyroptotic signaling by CBD. Simultaneously, CBD can repress aerobic glycolysis through modulation of the ATF4-IGFBP1-Akt axis, due to the depletion of ATP and crucial intermediate metabolites. Collectively, these observations indicate that CBD could be considered as a potential compound for HCC therapy.

Protective effects of cannabidiol on the membrane proteins of skin keratinocytes exposed to hydrogen peroxide via participation in the proteostasis network

Hydrogen peroxide (H₂O₂) is widely used in clinical practice due to its antiseptic properties and its ability to heal wounds. However, due to its involvement in the formation of ROS, H₂O₂ causes several side effects, including disorders of the metabolism of skin cells and the development of chronic inflammation mediated by oxidative stress. Therefore, this study evaluated the effects of cannabidiol (CBD), a phytocannabinoid known for its antioxidant and anti-inflammatory properties, on the proteome of keratinocyte membranes exposed to H₂O₂. Overall, the hydrogen peroxide caused the levels of several proteins to increase, while the treatment with CBD prevented these changes. Analysis of the protein-protein interaction network showed that the significant changes mainly involved proteins with important roles in the proteasomal activity, protein folding processes (regulatory subunit of the proteasome 26S 6A, beta proteasome subunit type 1, chaperonin 60 kDa), protein biosynthesis (40S ribosomal proteins S16, S2 and ubiquitin-S27a), regulation of the redox balance (carbonyl reductase [NADPH] 1 and NAD(P)H [quinone] 1 dehydrogenase) and cell survival (14-3-3 theta protein). Additionally, CBD reduced the total amount of MDA, 4-HNE and 4-ONE-protein adducts. Therefore, we conclude that CBD partially prevents the changes induced by hydrogen peroxide by reducing oxidative stress and maintaining proteostasis networks. Moreover, our results indicate that combination therapy with CBD may bring a promising approach in the clinical use of hydrogen peroxide by preventing its pro-oxidative and pro-inflammatory effect through potential participation of CBD in membrane mediated molecular signaling.

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CBD prevents H₂O₂-induced changes in keratinocytes membrane proteomic profile.

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Protective effect of CBD could be mediated by alterations in proteostasis network.

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CBD promotes antioxidative and pro-survival cellular response.

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CBD reduces formation of lipid peroxidation products-protein adducts.

Regulatory Effects of Cannabidiol on Mitochondrial Functions: A Review

Cannabidiol (CBD) is part of a group of phytocannabinoids derived from Cannabissativa. Initial work on CBD presumed the compound was inactive, but it was later found to exhibit antipsychotic, anti-depressive, anxiolytic, and antiepileptic effects. In recent decades, evidence has indicated a role for CBD in the modulation of mitochondrial processes, including respiration and bioenergetics, mitochondrial DNA epigenetics, intrinsic apoptosis, the regulation of mitochondrial and intracellular calcium concentrations, mitochondrial fission, fusion and biogenesis, and mitochondrial ferritin concentration and mitochondrial monoamine oxidase activity regulation. Despite these advances, current data demonstrate contradictory findings with regard to not only the magnitude of effects mediated by CBD, but also to the direction of effects. For example, there are data indicating that CBD treatment can increase, decrease, or have no significant effect on intrinsic apoptosis. Differences between studies in cell type, cell-specific response to CBD, and, in some cases, dose of CBD may help to explain differences in outcomes. Most studies on CBD and mitochondria have utilized treatment concentrations that exceed the highest recorded plasma concentrations in humans, suggesting that future studies should focus on CBD treatments within a range observed in pharmacokinetic studies. This review focuses on understanding the mechanisms of CBD-mediated regulation of mitochondrial functions, with an emphasis on findings in neural cells and tissues and therapeutic relevance based on human pharmacokinetics.

Cannabidiol in Neurological and Neoplastic Diseases: Latest Developments on the Molecular Mechanism of Action

As the major nonpsychotropic constituent of Cannabis sativa, cannabidiol (CBD) is regarded as one of the most promising therapeutic agents due to its proven effectiveness in clinical trials for many human diseases. Due to the urgent need for more efficient pharmacological treatments for several chronic diseases, in this review, we discuss the potential beneficial effects of CBD for Alzheimer's disease, epilepsy, multiple sclerosis, and neurological cancers. Due to its wide range of pharmacological activities (e.g., antioxidant, anti-inflammatory, and neuroprotective properties), CBD is considered a multimodal drug for the treatment of a range of neurodegenerative disorders, and various cancer types, including neoplasms of the neural system. The different mechanisms of action of CBD are here disclosed, together with recent progress in the use of this cannabis-derived constituent as a new therapeutic approach.