Systematic Review and Meta-analysis: The Association Between Serum Ustekinumab Trough Concentrations and Treatment Response in Inflammatory Bowel Disease.

BACKGROUND: Optimizing therapy and monitoring response are integral aspects of inflammatory bowel disease treatment. We conducted a systematic review and meta-analysis to determine whether serum ustekinumab trough concentrations during maintenance therapy were associated with ustekinumab treatment response in patients with inflammatory bowel disease. METHODS: A systematic review was performed to March 21, 2022, to identify studies using MEDLINE, EMBASE, and the Cochrane library. We included studies that reported the association between serum ustekinumab trough concentrations with clinical or endoscopic remission. Outcome measures were combined across studies using the random-effects model with an odds ratio (OR) for binary outcomes of endoscopic and clinical remission. RESULTS: We identified 14 observational studies that were included in the analysis for clinical remission (919 patients, 63% with Crohn's disease) or endoscopic remission (290 patients, all with Crohn's disease). Median ustekinumab trough concentrations were higher amongst individuals achieving clinical remission compared with those not achieving remission (mean difference, 1.6 ug/mL; 95% confidence interval [CI], 0.21-3.01 ug/mL). Furthermore, individuals with median serum trough concentration in the fourth quartile were significantly more likely to achieve clinical (OR, 3.61; 95% CI, 2.11-6.20) but not endoscopic remission (OR, 4.67; 95% CI, 0.86-25.19) compared with those with first quartile median trough concentrations. CONCLUSION: Based on the results of this meta-analysis primarily relating to patients with Crohn's disease on maintenance ustekinumab treatment, it appears that there is an association between higher ustekinumab trough concentration and clinical outcomes. Prospective studies are required to determine whether proactive dose adjustments of ustekinumab therapy provides additional clinical benefit.

This meta-analysis of 14 observational studies found an association between better clinical outcomes and higher trough ustekinumab levels for maintenance treatment in inflammatory bowel disease.

Protein kinase C{gamma} mediates regulation of proliferation by the serotonin 5-hydroxytryptamine receptor 2B.

Activation of the 5-hydroxytryptamine receptor 2B (5-HT(2B)), a G(q/11) protein-coupled receptor, results in proliferation of various cell types. The 5-HT(2B) receptor is also expressed on the pacemaker cells of the gastrointestinal tract, the interstitial cells of Cajal (ICC), where activation triggers ICC proliferation. The goal of this study was to characterize the mitogenic signal transduction cascade activated by the 5-HT(2B) receptor. All of the experiments were performed on mouse small intestine primary cell cultures. Activation of the 5-HT(2B) receptor by its agonist BW723C86 induced proliferation of ICC. Inhibition of phosphatidylinositol 3-kinase by LY294002 decreased base-line proliferation but had no effect on 5-HT(2B) receptor-mediated proliferation. Proliferation of ICC through the 5-HT(2B) receptor was inhibited by the phospholipase C inhibitor U73122 and by the inositol 1,4,5-trisphosphate receptor inhibitor Xestospongin C. Calphostin C, the alpha, beta, gamma, and micro protein kinase C (PKC) inhibitor Gö6976, and the alpha, beta, gamma, delta, and zeta PKC inhibitor Gö6983 inhibited 5-HT(2B) receptor-mediated proliferation, indicating the involvement of PKC alpha, beta, or gamma. Of all the PKC isoforms blocked by Gö6976, PKCgamma and micro mRNAs were found by single-cell PCR to be expressed in ICC. 5-HT(2B) receptor activation in primary cell cultures obtained from PKCgamma(-/-) mice did not result in a proliferative response, further indicating the requirement for PKCgamma in the proliferative response to 5-HT(2B) receptor activation. The data demonstrate that the 5-HT(2B) receptor-induced proliferative response of ICC is through phospholipase C, [Ca(2+)](i), and PKCgamma, implicating this PKC isoform in the regulation of cellular proliferation.

Treatment options for hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is frequently diagnosed at advanced stages and has a high mortality rate. With improved survival of patients with cirrhotic liver disease and increased prevalence of chronic hepatitis C viral infections, a rise in the number of HCC cases is being reported worldwide. Early diagnosis and treatment can significantly improve the prognosis of patients with HCC. Although surgical resection is an important potentially curative therapy for liver tumors, in appropriately selected patients, liver transplantation has been shown to achieve excellent survival rates for a solid tumor. Locally ablative and locoregional therapies in the form of percutaneous ethanol injection, radiofrequency ablation, transcatheter arterial chemoembolization and transcatheter arterial radioembolization (TheraSphere) are viable options in patients with unresectable HCC. Unfortunately, the role of systemic therapy has been very limited in the treatment of these patients. Novel treatment options based on an improved understanding of the molecular pathogenesis of HCC are being explored. These targeted molecular therapies are aimed at growth factors and their receptors, intracellular signal transduction and cell cycle control. A substantial improvement in outcomes of intermediate and advanced stage HCC is expected with the advent of these targeted therapies, used in combination with surgical or locoregional therapies. Recent positive results from a large Phase III study of the receptor tyrosine kinase inhibitor, sorafenib, hold great promise in the treatment of HCC.