Disordered signaling in myeloproliferative neoplasms

Association between COX-2 -1195G>A polymorphism and gastrointestinal cancer risk: A meta-analysis

AIM

To perform a meta-analysis to investigate the association between cyclooxygenase-2 (COX-2) -1195G>A gene polymorphism and gastrointestinal cancers.

METHODS

Publications related to the COX-2 -1195G>A gene polymorphism and gastrointestinal cancers published before July 2016 were retrieved from PubMed, EMBASE, Web of Science, China Biological Medicine Database, China National Knowledge Infrastructure, and CQVIP Database. Meta-analysis was performed using Stata11.0 software. The strength of the association was evaluated by calculating the combined odds ratios (ORs) and the corresponding 95%CIs. The retrieved publications were excluded or included one by one for sensitivity analysis. In addition, the funnel plot, Begg’s rank correlation test, and Egger’s linear regression method were applied to analyse whether the included publications had publication bias.

RESULTS

A total of 24 publications related to the COX-2 -1195G>A gene polymorphism were included, including 28 studies involving 11043 cases and 18008 controls. The meta-analysis results showed that the COX-2 -1195G>A gene polymorphism significantly correlated with an increased risk of gastrointestinal cancers, particularly gastric cancer (A vs G: OR = 1.35; AA/AG vs GG: OR = 1.54; AA vs GG/AG: OR = 1.43; AA vs GG: OR = 1.80; AG vs GG: OR = 1.35). Compared to the Caucasian population in America and Europe, the COX-2 -1195G>A gene polymorphism in the Asian population (A vs G: OR = 1.30; AA/AG vs GG: OR = 1.50; AA vs GG/AG: OR = 1.35; AA vs GG: OR = 1.71; AG vs GG: OR = 1.37) significantly increased gastrointestinal cancer risk. The sensitivity analysis (P < 0.05) and the false positive report probability (P < 0.2) confirmed the reliability of the results.

CONCLUSION

The results showed that the COX-2 -1195G>A gene polymorphism might be a potential risk factor for gastrointestinal cancers. Further validation by a large homogeneous study is warranted.

N, Kuppusamy P, Purandare AV. Discovery of a Highly Selective JAK2 Inhibitor, BMS-911543, for the Treatment of Myeloproliferative Neoplasms

JAK2 kinase inhibitors are a promising new class of agents for the treatment of myeloproliferative neoplasms and have potential for the treatment of other diseases possessing a deregulated JAK2-STAT pathway. X-ray structure and ADME guided refinement of C-4 heterocycles to address metabolic liability present in dialkylthiazole 1 led to the discovery of a clinical candidate, BMS-911543 (11), with excellent kinome selectivity, in vivo PD activity, and safety profile.

Discovery of 1-methyl-1H-imidazole derivatives as potent Jak2 inhibitors

Structure based design, synthesis, and biological evaluation of a novel series of 1-methyl-1H-imidazole, as potent Jak2 inhibitors to modulate the Jak/STAT pathway, are described. Using the C-ring fragment from our first clinical candidate AZD1480 (24), optimization of the series led to the discovery of compound 19a, a potent, orally bioavailable Jak2 inhibitor. Compound 19a displayed a high level of cellular activity in hematopoietic cell lines harboring the V617F mutation and in murine BaF3 TEL-Jak2 cells. Compound 19a demonstrated significant tumor growth inhibition in a UKE-1 xenograft model within a well-tolerated dose range.

Investigational Janus kinase inhibitors

INTRODUCTION

Dysregulation of the Janus kinase-signal transducer and activator of transcription (JAK-STAT) pathway is central to the pathophysiology of myeloproliferative neoplasms (MPN). Small molecule inhibitors of JAK family members are currently under investigation for the treatment of MPN. Of these, ruxolitinib has received approval for clinical use in myelofibrosis in the United States and Europe.

AREAS COVERED

The clinical results and future development program of major JAK inhibitors, including ruxolitinib, CYT387, SAR302503, lestaurtinib, pacritinib, XL-019, LY2784544, BMS-911453, AZD1480 and NS-018 are reviewed.

EXPERT OPINION

JAK inhibitors are effective in relieving organomegaly (splenomegaly and hepatomegaly) and constitutional symptoms of myelofibrosis and some modulate inflammatory cytokines. However, they have little impact on disease burden and bone marrow fibrosis. The relationship between clinical efficacy, toxicity profile and specificity of JAK family member inhibition (i.e., JAK2 specific vs JAK1/JAK2 active) is poorly defined. Novel resistance mechanisms including heterodimerization of JAK2 with other JAK family members have been described. It is likely that the future lies in the use of rational drug combinations that target multiple signaling pathways.