Classical cannabinoid receptors as target in cancer-induced bone pain: a systematic review, meta-analysis and bioinformatics validation.

To test the hypothesis that genetic and pharmacological modulation of the classical cannabinoid type 1 (CB1) and 2 (CB2) receptors attenuate cancer-induced bone pain, we searched Medline, Web of Science and Scopus for relevant skeletal and non-skeletal cancer studies from inception to July 28, 2022. We identified 29 animal and 35 human studies. In mice, a meta-analysis of pooled studies showed that treatment of osteolysis-bearing males with the endocannabinoids AEA and 2-AG (mean difference [MD] - 24.83, 95% confidence interval [95%CI] - 34.89, - 14.76, p < 0.00001) or the synthetic cannabinoid (CB) agonists ACPA, WIN55,212-2, CP55,940 (CB1/2-non-selective) and AM1241 (CB2-selective) (MD - 28.73, 95%CI - 45.43, - 12.02, p = 0.0008) are associated with significant reduction in paw withdrawal frequency. Consistently, the synthetic agonists AM1241 and JWH015 (CB2-selective) increased paw withdrawal threshold (MD 0.89, 95%CI 0.79, 0.99, p < 0.00001), and ACEA (CB1-selective), AM1241 and JWH015 (CB2-selective) reduced spontaneous flinches (MD - 4.85, 95%CI - 6.74, - 2.96, p < 0. 00001) in osteolysis-bearing male mice. In rats, significant increase in paw withdrawal threshold is associated with the administration of ACEA and WIN55,212-2 (CB1/2-non-selective), JWH015 and AM1241 (CB2-selective) in osteolysis-bearing females (MD 8.18, 95%CI 6.14, 10.21, p < 0.00001), and treatment with AM1241 (CB2-selective) increased paw withdrawal thermal latency in males (mean difference [MD]: 3.94, 95%CI 2.13, 5.75, p < 0.0001), confirming the analgesic capabilities of CB1/2 ligands in rodents. In human, treatment of cancer patients with medical cannabis (standardized MD - 0.19, 95%CI - 0.35, - 0.02, p = 0.03) and the plant-derived delta-9-THC (20 mg) (MD 3.29, CI 2.24, 4.33, p < 0.00001) or its synthetic derivative NIB (4 mg) (MD 2.55, 95%CI 1.58, 3.51, p < 0.00001) are associated with reduction in pain intensity. Bioinformatics validation of KEGG, GO and MPO pathway, function and process enrichment analysis of mouse, rat and human data revealed that CB1 and CB2 receptors are enriched in a cocktail of nociceptive and sensory perception, inflammatory, immune-modulatory, and cancer pathways. Thus, we cautiously conclude that pharmacological modulators of CB1/2 receptors show promise in the treatment of cancer-induced bone pain, however further assessment of their effects on bone pain in genetically engineered animal models and cancer patients is warranted.

TRAF6 as a potential target in advanced breast cancer: a systematic review, meta-analysis, and bioinformatics validation.

TRAF6 has emerged as a key regulator of breast cancer (BCa). However, the TRAF family constitutes of seven members that exhibit distinct and overlapping functions. To explore which TRAF represents a potential druggable target for BCa treatment, we searched Medline, Web of Science and Scopus for relevant studies from inception to June 27, 2021. We identified 14 in vitro, 11 in vivo and 4 human articles. A meta-analysis of pharmacological studies showed that in vitro inhibition of TRAF2/4 (mean difference (MD): - 57.49, 95% CI: - 66.95, - 48.02, P < 0.00001) or TRAF6 (standard(Std.)MD: - 4.01, 95% CI: - 5.75, - 2.27, P < 0.00001) is associated with reduction in BCa cell migration. Consistently, inhibition of TRAF2/4 (MD: - 51.08, 95% CI: - 64.23, - 37.94, P < 0.00001) and TRAF6 (Std.MD: - 2.80, 95% CI: - 4.26, - 1.34, P = 0.0002) is associated with reduced BCa cell invasion, whereas TRAF2/4 inhibition (MD: - 40.54, 95% CI: - 52.83, - 28.26, P < 0.00001) is associated with reduced BCa cell adhesion. Interestingly, only inhibition of TRAF6 (MD: - 21.46, 95% CI: - 30.40, - 12.51, P < 0.00001) is associated with reduced cell growth. In animal models of BCa, administration of pharmacological inhibitors of TRAF2/4 (Std.MD: - 3.36, 95% CI: - 4.53, - 2.18, P < 0.00001) or TRAF6 (Std.MD: - 4.15, 95% CI: - 6.06, - 2.24, P < 0.0001) in mice is associated with reduction in tumour burden. In contrast, TRAF6 inhibitors (MD: - 2.42, 95% CI: - 3.70, - 1.14, P = 0.0002) reduced BCa metastasis. In BCa patients, high expression of TRAF6 (Hazard Ratio: 1.01, CI: 1.01, 1.01, P < 0.00001) is associated with poor survival rate. Bioinformatics validation of clinical and pathway and process enrichment analysis in BCa patients confirmed that gain/amplification of TRAF6 is associated with secondary BCa in bone (P = 0.0079), and poor survival rate (P < 0.05). Overall, TRAF6 inhibitors show promise in the treatment of metastatic BCa. However, low study number and scarcity of evidence from animal and human studies may limit the translation of present findings into clinical practice.

Case Report: Brachydactyly Type A1 Induced by a Novel Variant of in-Frame Insertion in the IHH Gene.

Brachydactyly type A1 (BDA1) is an autosomal dominant inherited disease characterized by the shortness/absence of the middle phalanges, which can be induced by mutations in the Indian hedgehog gene (IHH). Rheumatoid arthritis (RA) is a chronic, systemic autoimmune disease characterized by joint destruction, synovitis, and the presence of autoantibodies. In this study, the proband was diagnosed with both BDA1 and RA. We performed whole-exome sequencing in a four-generation Chinese family to investigate their inherited causal mutation to BDA1. A novel in-frame insertion variant in IHH: NM_002,181.4: c.383_415dup/p.(R128_H138dup) was identified in the BDA1 pedigree. This insertion of 11 amino acids was located in the highly conserved amino-terminal signaling domain of IHH and co-segregated with the disease status. This adds one to the total number of different IHH mutations found to cause BDA1. Moreover, we found a potential causal germline variant in CRY1 for a molecular biomarker of RA (i.e., a high level of anti-cyclic citrullinated peptide). Collectively, we identified novel variants in IHH for inherited BDA1, which highlights the important role of this gene in phalange development.

Anti-inflammatory, but not osteoprotective, effect of the TRAF6/CD40 inhibitor 6877002 in rodent models of local and systemic osteolysis.

NFκB plays a key role in inflammation and skeletal disorders. Previously, we reported that pharmacological inhibition of NFκB at the level of TRAF6 suppressed RANKL, CD40L and IL1ß-induced osteoclastogenesis and attenuated cancer-induced bone disease. TNFα is also known to regulate TRAF6/NFκB signalling, however the anti-inflammatory and osteoprotective effects associated with inhibition of the TNFα/TRAF6/NFκB axis have not been investigated. Here, we show that in vitro and ex vivo exposure to the verified small-molecule inhibitor of TRAF6, 6877002 prevented TNFα-induced NFκB activation, osteoclastogenesis and calvarial osteolysis, but it had no effects on TNFα-induced apoptosis or growth inhibition in osteoblasts. Additionally, 6877002 disrupted T-cells support for osteoclast formation and synoviocyte motility, without affecting the viability of osteoblasts in the presence of T-cells derived factors. Using the collagen-induced arthritis model, we show that oral and intraperitoneal administration of 6877002 in mice reduced joint inflammation and arthritis score. Unexpectedly, no difference in trabecular and cortical bone parameters were detected between vehicle and 6877002 treated mice, indicating lack of osteoprotection by 6877002 in the arthritis model described. Using two independent rodent models of osteolysis, we confirmed that 6877002 had no effect on trabecular and cortical bone loss in both osteoporotic rats or RANKL- treated mice. In contrast, the classic anti-osteolytic alendronate offered complete osteoprotection in RANKL- treated mice. In conclusion, TRAF6 inhibitors may be of value in the management of the inflammatory component of bone disorders, but may not offer protection against local or systemic bone loss, unless combined with anti-resorptive therapy such as bisphosphonates.

Association of cannabinoid receptor modulation with normal and abnormal skeletal remodelling: A systematic review and meta-analysis of in vitro, in vivo and human studies.

To address the inconsistent findings from studies that used different models to explore the role of classical cannabinoid type 1 (CB1) and 2 (CB2) receptors in skeletal remodelling, we searched Medline, Web of Science and Embase for relevant studies from inception to June 23, 2020. We identified 38 in vitro, 34 in vivo and 9 human studies. A meta-analysis of in vitro studies showed that exposure to the inverse-agonists AM251 (mean difference [MD]:-26.75, 95% confidence interval [CI]:-45.36,-8.14, p = 0.005), AM630 (standardised[std.] MD:-3.11, CI:-5.26,-0.97, p = 0.004; SR144528, std.MD:-4.88, CI -7.58,-2.18, p = 0.0004) and CBD (std.MD:-1.39, CI -2.64,-0.14, p = 0.03) is associated with reduced osteoclastogenesis, whereas the endocannabinoid 2-AG (std.MD:2.00, CI:0.11-3.89, p = 0.04) and CB2-selective agonist HU308 (MD:19.38, CI:11.75-27.01, p < 0.00001) were stimulatory. HU308 also enhanced osteoblast differentiation (std.MD:2.22, CI:0.95-3.50, p = 0.0006) and activity (std.MD:2.97, CI:1.22-4.71, p = 0.0008). In models of bone loss, CB1/2 deficiency enhanced peak bone volume (std.MD:3.70, CI:1.77-5.63, p = 0.0002) but reduced bone formation (std.MD:-0.54, CI:-0.90,-0.17, p = 0.004) in female mice. In male rats, CB1/2 deficiency (std.MD:2.31, CI:0.30-4.33, p = 0.02) and AM251 or CBD treatments (std.MD:2.19, CI:0.46-3.93, p = 0.01) enhanced bone volume. CB1/2 deficiency (std.MD:9.78, CI:4.96-14.61, p < 0.0001) and AM251 or AM630 treatments (std.MD:28.19, CI:19.13-37.25, p < 0.0001) were associated with osteoprotection. The CB2-selective agonists JWH133 and 4Q3C enhanced bone volume in arthritic rodents (std.MD:14.45, CI:2.08-26.81, p = 0.02). In human, CB2 SNPs (AA:rs2501431, MD:-0.28, CI:-0.55,-0.01, p = 0.04; CC:rs2501432, MD:-0.29, CI:-0.56,-0.02, p = 0.03) were associated with reduced bone mineral density, however the association of Marijuana use remains unclear. Thus, CB1/2 modulation is associated with altered bone metabolism, however findings are confounded by low study number and heterogenicity of models.

Presence and diagnostic value of circulating tsncRNA for ovarian tumor.

tRNA-derived small non-coding RNAs (tsncRNAs), a class of newly defined small non-coding RNA, have been considered to be involved in various cellular biological processes through regulating gene expression at both transcriptional and post-transcriptional level. However, the presence of circulating tsncRNAs and their diagnostic potential is largely unclear. In this study, we investigate the serum-derived public transcriptome data from ovarian tumor patients and non-cancer controls, and find that circulating tsncRNAs cover a high proportion of total small RNA and are non-random degradation products in serum (ranging from 2.5-29.4%), which are enriched in several specific types of related tRNA (e.g., Gly-tRNA). Particularly, four tsncRNAs are differentially expressed in serum from cancer patients compared to those from healthy controls, and can predict abnormal cell proliferation with high accuracy. Our results reveal the ubiquitous presence of circulating tsncRNAs in serum, and diagnostic potential of specific tsncRNAs for ovarian tumor.

Regulatory Network and Prognostic Effect Investigation of PIP4K2A in Leukemia and Solid Cancers.

Germline variants of PIP4K2A impact susceptibility of acute lymphoblastic leukemia (ALL) through inducing its overexpression. Although limited reports suggested the oncogenic role of PIP4K2A in cancers, regulatory network and prognostic effect of this gene remains poorly understood in tumorigenesis and leukemogenesis. In this study, we conducted genome-wide gene expression association analyses in pediatric B-ALL cohorts to discover expression associated genes and pathways, which is followed by the bioinformatics analyses to investigate the prognostic role of PIP4K2A and its related genes in multiple cancer types. 214 candidates were identified to be significantly associated with PIP4K2A expression in ALL patients, with known cancer-related genes rankings the top (e.g., RAC2, RBL2, and TFDP1). These candidates do not only tend to be clustered in the same types of leukemia, but can also separate the patients into novel molecular subtypes. PIP4K2A is noticed to be frequently overexpressed in multiple other types of leukemia and solid cancers from cancer cohorts including TCGA, and associated with its candidates in subtype-specific and cancer-specific manners. Interestingly, the association status varied in tumors compared to their matched normal tissues. Moreover, PIP4K2A and its related candidates exhibit stage-independent prognostic effects in multiple cancers, mostly with its lower expression significantly associated with longer overall survival (p < 0.05). Our findings reveal the transcriptional regulatory network of PIP4K2A in leukemia, and suggest its potentially important role on molecular subtypes of multiple cancers and subsequent treatment outcomes.