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.

LAIR1 drives glioma progression by nuclear focal adhesion kinase dependent expressions of cyclin D1 and immunosuppressive chemokines/cytokines.

Leukocyte-associated immunoglobulin-like receptor-1 (LAIR1), an immune receptor containing immunoreceptor tyrosine-based inhibiory motifs (ITIMs), has emerged as an attractive target for cancer therapy. However, the intrinsic function of LAIR1 in gliomas remains unclear. In this study, the poor prognosis of glioma patients and the malignant proliferation of glioma cells in vitro and in vivo were found to be closely correlated with LAIR1. LAIR1 facilitates focal adhesion kinase (FAK) nuclear localization, resulting in increased transcription of cyclin D1 and chemokines/cytokines (CCL5, TGFß2, and IL33). LAIR1 specifically supports in the immunosuppressive glioma microenvironment via CCL5-mediated microglia/macrophage polarization. SHP2Q510E (PTP domain mutant) or FAKNLM (non-nuclear localizing mutant) significantly reversed the LAIR1-induced growth enhancement in glioma cells. In addition, LAIR1Y251/281F (ITIMs mutant) and SHP2Q510E mutants significantly reduced FAK nuclear localization, as well as CCL5 and cyclin D1 expression. Further experiments revealed that the ITIMs of LAIR1 recruited SH2-containing phosphatase 2 (SHP2), which then interacted with FAK and induced FAK nuclear localization. This study uncovered a critical role for intrinsic LAIR1 in facilitating glioma malignant progression and demonstrated a requirement for LAIR1 and SHP2 to enhance FAK nuclear localization.

A novel mechanism of 6-methoxydihydroavicine in suppressing ovarian carcinoma by disrupting mitochondrial homeostasis and triggering ROS/ MAPK mediated apoptosis.

Introduction: Alkaloids derived from M. cordata (Papaveraceae family), have been found to display antineoplastic activity in several types of cancer. However, the antitumor effects and mechanisms of a new alkaloid extracted from the fruits of M. cordata, named 6-Methoxydihydroavicine (6-ME), remains unclear in the case of ovarian cancer (OC). Methods: CCK-8 assay was employed to analyze the cell viabilities of OC cells. RTCA, and colony-formation assays were performed to measure OC cell growth. Alterations in apoptosis and ROS levels were detected by flow cytometry in accordance with the instructions of corresponding assay kits. A Seahorse XFe96 was executed conducted to confirm the effects of 6-ME on cellular bioenergetics. Western blot and q-RT-PCR were conducted to detect alterations in target proteins. The subcutaneous xenografted tumor model of OC was used to further validate the anti-tumor activity of 6-ME in vivo. Results: Here, we reported for the first time that 6-ME inhibits OC cells growth in vitro and in vivo. Meanwhile, we found that 6-ME showed great antineoplastic activities by disrupting mitochondria homeostasis and promoting apoptosis in OC cells. Further investigation of the upstream signaling of apoptosis revealed that 6-ME-triggered apoptosis was induced by reactive oxygen species (ROS)-mediated mitogen-activated protein kinase (MAPK) activation and mitochondria dysfunction in OC cells. Furthermore, we found oxaloacetic acid (OAA), a crucial metabolite has been proved to be related to NADPH production, can block the cytotoxicity and accumulation of ROS caused by 6-ME in OC cells. Discussion: In summary, our data show that 6-ME exhibits cytotoxicity to OC cells in a ROS-dependent manner by interrupting mitochondrial respiration homeostasis and inducing MAPK-mediated apoptosis. This evidence suggests that 6-ME is a promising remedy for OC intervention.

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 Efficacy of Drug Injection in the Treatment of Pathological Scar: A Network Meta-analysis.

BACKGROUND: Pathological scars mainly include hyperplastic scars and keloids, and there is no uniform treatment standard for the treatment of pathological scar in clinic now. Drug injection in the treatment of pathological scar is widely used because of its advantages of less trauma and simple operation. Therefore, we used a network meta-analysis to compare the curative effect of four kinds of drugs which are commonly used in the treatment of pathological scar such as botulinum toxin type A, corticosteroids (including diprospan and triamcinolone acetonide (TAC)), verapamil and 5-fluorouracil (5-FU), systematically. It is hoped that our study will provide evidence for the choice of drugs in the treatment of pathological scar by injection. METHODS: Relevant articles from Wanfang, VIP, CNKI, PubMed, Cochrane Library and Embase databases were extracted by us. They were included into a network meta-analysis to compare the four kinds of drugs which are commonly used in the treatment of pathological scar. RESULTS: The network meta-analysis included a total of 1513 patients from 23 studies. Through meta-analysis, we found that the efficacy of botulinum toxin type A combined with corticosteroid drugs was best in the treatment of pathological scar by injection. There was no significant difference between botulinum toxin type A, corticosteroids combined with 5 Fu, verapamil and 5-FU. The efficacy of corticosteroids combined with 5-FU was better than that of corticosteroids alone and verapamil alone, but there was no significant difference between them and 5-FU. Further, the order of efficacy predicted by the SUCRA curve was as follows: botulinum toxin type A combined with corticosteroids > corticosteroids combined with 5-FU > botulinum toxin type A > corticosteroids > 5-FU > verapamil. Moreover, no publication bias was found in the funnel diagram. CONCLUSION: In the injection treatment of pathological scar, we recommend the combined injection of two drugs, especially botulinum toxin type A combined with corticosteroids. The effective treatment of botulinum toxin type A combined with corticosteroids in the treatment of pathological scar is as follows: Patients were treated once monthly with intralesional injection of TAC (0.1 ml/cm3) mixed with botulinum toxin type A (2.5 IU/cm3) for a total of 3 treatments. However, there are still limitations in this network meta-analysis, and its conclusion still needs to be further confirmed by more randomized controlled trials. LEVEL OF EVIDENCE III: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Methylation status of the PTEN gene in adenoid cystic carcinoma cells.

The tumor suppressor phosphatase and tensin homolog deleted on chromosome 10 (PTEN) is deficient in various types of human tumors due to mutations or epigenetic alterations. PTEN promoter hypermethylation is a major epigenetic silencing mechanism leading to self-repression in these tumors. The present study aimed to investigate whether PTEN promoter methylation is involved in the regulation of the PTEN gene in adenoid cystic carcinoma (ACC) cells. The expression of PTEN in ACC-2 cells was found to be significantly lower than that in normal salivary gland epithelial cells using RT-PCR analysis. The existence of CpG island methylation in the PETN promoter region in ACC-2 cells was demonstrated by methylation-specific PCR (MSP) analysis and direct sequencing of MSP product. RT-PCR, Western blot analysis and luciferase assay showed that mRNA and protein expression and the promoter activity of PTEN in ACC-2 cells treated with the DNA methylation inhibitor 5-aza-2-deoxycytidine were significantly up-regulated in a time-dependent manner. These results indicate that the hypermethylation of the PTEN promoter region leads to lower expression of PTEN gene in ACC cells, which aids in the development of PTEN as a molecular marker for the early diagnosis of this carcinoma.