Plain language summary of zanubrutinib or ibrutinib in chronic lymphocytic leukemia that is resistant to treatment or has come back after treatment.

What is this summary about? This is a plain language summary of a research study called ALPINE. The study involved people who had been diagnosed with, and previously treated at least once for, relapsed or refractory chronic lymphocytic leukemia (CLL) or small lymphocytic lymphoma (SLL).Lymphocytes help to find and fight off viruses and infections in the body, but when someone has CLL or SLL, the body creates abnormal lymphocytes, leaving the patient with a weakened immune system and susceptible to illness. In CLL, these lymphocytes are in the bone marrow and bloodstream, whereas for SLL, they are mostly found in the lymph nodes, such as those in the neck.How was the research done? The ALPINE study was designed to directly compare the cancer-fighting effects and side effects of zanubrutinib and ibrutinib as treatment for patients with relapsed or refractory CLL/SLL.What were the results? After 30 months, zanubrutinib was more effective than ibrutinib at reducing and keeping the cancer from coming back. Clinical Trial Registration: NCT03734016 (ClinicalTrials.gov).

Pericyte derivation and transplantation for blood-CNS barrier reconstitution in CNS disorders.

Disruption of the blood-central nervous system barrier (BCB) is increasingly recognized as a pathological factor in diseases and trauma of the central nervous system. Despite the neuropathological impact, current treatment modalities do not target the BCB; strategies to reconstitute the impaired BCB have been restricted to nutritional and dietary remedies. As an integral cell type in the neurovascular unit, pericytes are crucial to the development, maintenance, and repair of the BCB. As such, pericytes are well poised as cellular agents for reconstitution of the impaired BCB. Here, we summarize recent revelations regarding the role of BCB disruption in diseases and trauma of the central nervous system and highlight how pericytes are harnessed to provide targeted therapeutic effect in each case. This review will also address how recent advances in pericyte derivation strategies can serve to overcome practical hurdles in the clinical use of pericytes.

Differential Target Multiplexed Spinal Cord Stimulation for the Treatment of Chronic Intractable Upper Limb Pain: 12-Month Results From a Prospective, Multicenter Study.

OBJECTIVES: This prospective, open-label, single-arm, multicenter study evaluated the use of differential target multiplexed (DTM) spinal cord stimulation (SCS) therapy for chronic upper limb pain (ULP). MATERIALS AND METHODS: A total of 58 candidates for SCS who had chronic ULP were enrolled at 11 sites in the USA. The safety and effectiveness of DTM SCS for treating chronic intractable ULP were evaluated over 12 months. The primary end point was the percentage of responders (≥50% ULP relief versus baseline) to treatment at three months after device activation. This study also evaluated the extent of disability, patient satisfaction, and patient global impression of change with DTM SCS therapy. RESULTS: The mean baseline pain score (10-cm visual analog scale [VAS-10]) for ULP was 7.2 cm, with a mean age of 56 years and mean ULP duration of ten years; 47 subjects were assessed at the primary end point. The percentage of ULP responders was 92% at three months, which was consistent at six (91%) and 12 months (86%). Significant ULP relief (81% reduction in VAS-10) was observed at the primary end point and sustained throughout the study duration. Significant improvements in disability in addition to high levels (>95%) of satisfaction and feelings of improvement were reported. Frequency of study-related anticipated adverse events was in line with expectations of SCS therapy. CONCLUSION: In this patient population with difficult-to-treat conditions with limited clinical evidence of the effectiveness of SCS, subjects reported significant reduction in chronic ULP in response to treatment with DTM SCS.

Improved efficacy and safety of zanubrutinib versus ibrutinib in patients with relapsed/refractory chronic lymphocytic leukemia (R/R CLL) in China: a subgroup of ALPINE.

Chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) has different epidemiology in Chinese vs. Western patients, but there are few studies of CLL/SLL in large populations of Chinese patients. ALPINE is a global phase 3 trial investigating Bruton tyrosine kinase inhibitors zanubrutinib vs. ibrutinib to treat relapsed/refractory (R/R) CLL/SLL. Here we report results from the subgroup of Chinese patients. Adults with R/R CLL/SLL were randomized 1:1 to receive zanubrutinib (160 mg twice-daily) or ibrutinib (420 mg once-daily) until disease progression or unacceptable toxicity. Endpoints included overall response rate (ORR), progression-free survival (PFS), overall survival (OS), and safety. Data were analyzed descriptively. Ninety patients were randomized in China (zanubrutinib, n = 47; ibrutinib, n = 43). Baseline characteristics were balanced between groups, with fewer male patients in the zanubrutinib vs. ibrutinib group (55.3% vs. 69.8%). Median age was 60.5 years, 11% had del(17p) mutation, and 32% had tumor protein 53 (TP53) mutation. With median 25.3 months follow-up, ORR was 80.9% with zanubrutinib vs. 72.1% with ibrutinib. PFS was improved with zanubrutinib vs. ibrutinib (HR = 0.34 [95% CI, 0.15, 0.77]), and the HR for OS was 0.45 (95% CI, 0.14, 1.50). Rates of Grade ≥ 3 treatment-emergent adverse events (TEAEs; 64.4% vs. 72.1%), AEs leading to discontinuation (6.4% vs. 14.0%), and serious TEAEs (35.6% vs. 51.2%) were lower with zanubrutinib vs. ibrutinib. Zanubrutinib demonstrated improved ORR, PFS, and OS vs. ibrutinib and a more favorable safety profile in patients with R/R CLL/SLL in China. These results are consistent with the full global population of ALPINE. ClinicalTrials.gov: NCT03734016, registered November 7, 2018.

Neonatal GABAergic transmission primes vestibular gating of output for adult spatial navigation.

GABAergic interneurons are poised with the capacity to shape circuit output via inhibitory gating. How early in the development of medial vestibular nucleus (MVN) are GABAergic neurons recruited for feedforward shaping of outputs to higher centers for spatial navigation? The role of early GABAergic transmission in assembling vestibular circuits for spatial navigation was explored by neonatal perturbation. Immunohistochemistry and confocal imaging were utilized to reveal the expression of parvalbumin (PV)-expressing MVN neurons and their perineuronal nets. Whole-cell patch-clamp recording, coupled with optogenetics, was conducted in vitro to examine the synaptic function of MVN circuitry. Chemogenetic targeting strategy was also employed in vivo to manipulate neuronal activity during navigational tests. We found in rats a neonatal critical period before postnatal day (P) 8 in which competitive antagonization of GABAergic transmission in the MVN retarded maturation of inhibitory neurotransmission, as evidenced by deranged developmental trajectory for excitation/inhibition ratio and an extended period of critical period-like plasticity in GABAergic transmission. Despite increased number of PV-expressing GABAergic interneurons in the MVN, optogenetic-coupled patch-clamp recording indicated null-recruitment of these neurons in tuning outputs along the ascending vestibular pathway. Such perturbation not only offset output dynamics of ascending MVN output neurons, but was further accompanied by impaired vestibular-dependent navigation in adulthood. The same perturbations were however non-consequential when applied after P8. Results highlight neonatal GABAergic transmission as key to establishing feedforward output dynamics to higher brain centers for spatial cognition and navigation.

Yeast heterochromatin stably silences only weak regulatory elements by altering burst duration.

Transcriptional silencing in Saccharomyces cerevisiae involves the generation of a chromatin state that stably represses transcription. Using multiple reporter assays, a diverse set of upstream activating sequence enhancers and core promoters were investigated for their susceptibility to silencing. We show that heterochromatin stably silences only weak and stress-induced regulatory elements but is unable to stably repress housekeeping gene regulatory elements, and the partial repression of these elements did not result in bistable expression states. Permutation analysis of enhancers and promoters indicates that both elements are targets of repression. Chromatin remodelers help specific regulatory elements to resist repression, most probably by altering nucleosome mobility and changing transcription burst duration. The strong enhancers/promoters can be repressed if silencer-bound Sir1 is increased. Together, our data suggest that the heterochromatic locus has been optimized to stably silence the weak mating-type gene regulatory elements but not strong housekeeping gene regulatory sequences.

Monoubiquitination empowers ubiquitin chain elongation.

Ubiquitination often generates lysine 48-linked polyubiquitin chains that signal proteolytic destruction of the protein target. A significant subset of ubiquitination proceeds by a priming/extending mechanism, in which a substrate is first monoubiquitinated with a priming E2-conjugating enzyme or a set of E3 ARIH/E2 enzymes specific for priming. This is then followed by ubiquitin (Ub) chain extension catalyzed by an E2 enzyme capable of elongation. This report provides further insights into the priming/extending mechanism. We employed reconstituted ubiquitination systems of substrates CK1α (casein kinase 1α) and ß-catenin by Cullin-RING E3 Ub ligases (CRLs) CRL4CRBN and CRL1ßTrCP, respectively, in the presence of priming E2 UbcH5c and elongating E2 Cdc34b (cell division cycle 34b). We have established a new "apyrase chase" strategy that uncouples priming from chain elongation, which allows accurate measurement of the decay rates of the ubiquitinated substrate with a defined chain length. Our work has revealed highly robust turnover of monoubiquitinated ß-catenin that empowers efficient polyubiquitination. The results of competition experiments suggest that the interactions between the ubiquitinated ß-catenin and CRL1ßTrCP are highly dynamic. Moreover, ubiquitination of the Ub-modified ß-catenin appeared more resistant to inhibition by competitors than the unmodified substrate, suggesting tighter binding with CRL1ßTrCP. These findings support a role for conjugated Ub in enhancing interactions with E3.

Modulation of Cullin-RING E3 ubiquitin ligase-dependent ubiquitination by small molecule compounds.

Cullin (CUL)-RING (Really Interesting New Gene) E3 ubiquitin (Ub) ligases (CRLs) are the largest E3 family. The E3 CRL core ligase is a subcomplex formed by the CUL C-terminal domain bound with the ROC1/RBX1 RING finger protein, which acts as a hub that mediates and organizes multiple interactions with E2, Ub, Nedd8, and the ARIH family protein, thereby resulting in Ub transfer to the E3-bound substrate. This report describes the modulation of CRL-dependent ubiquitination by small molecule compounds including KH-4-43, #33, and suramin, which target the CRL core ligases. We show that both KH-4-43 and #33 inhibit the ubiquitination of CK1α by CRL4CRBN. However, either compound's inhibitory effect on this reaction is significantly reduced when a neddylated form of CRL4CRBN is used. On the other hand, both #33 and KH-4-43 inhibit the ubiquitination of ß-catenin by CRL1ß-TrCP and Nedd8-CRL1ß-TrCP almost equally. Thus, neddylation of CRL1ß-TrCP does not negatively impact the sensitivity to inhibition by #33 and KH-4-43. These findings suggest that the effects of neddylation to alter the sensitivity of CRL inhibition by KH-4-43/#33 is dependent upon the specific CRL type. Suramin, a compound that targets CUL's basic canyon, can effectively inhibit CRL1/4-dependent ubiquitination regardless of neddylation status, in contrast to the results observed with KH-4-43/#33. This observed differential drug sensitivity of KH-4-43/#33 appears to echo CUL-specific Nedd8 effects on CRLs as revealed by recent high-resolution structural biology efforts. The highly diversified CRL core ligase structures may provide opportunities for specific targeting by small molecule modulators.

CRL4b Inhibition Ameliorates Experimental Autoimmune Encephalomyelitis Progression.

Multiple sclerosis, and its murine model experimental autoimmune encephalomyelitis (EAE), is a neurodegenerative autoimmune disease of the CNS characterized by T cell influx and demyelination. Similar to other autoimmune diseases, therapies can alleviate symptoms but often come with side effects, necessitating the exploration of new treatments. We recently demonstrated that the Cullin-RING E3 ubiquitin ligase 4b (CRL4b) aided in maintaining genome stability in proliferating T cells. In this study, we examined whether CRL4b was required for T cells to expand and drive EAE. Mice lacking Cul4b (Cullin 4b) in T cells had reduced EAE symptoms and decreased inflammation during the peak of the disease. Significantly fewer CD4+ and CD8+ T cells were found in the CNS, particularly among the CD4+ T cell population producing IL-17A, IFN-γ, GM-CSF, and TNF-α. Additionally, Cul4b-deficient CD4+ T cells cultured in vitro with their wild-type counterparts were less likely to expand and differentiate into IL-17A- or IFN-γ-producing effector cells. When wild-type CD4+ T cells were activated in vitro in the presence of the recently developed CRL4 inhibitor KH-4-43, they exhibited increased apoptosis and DNA damage. Treatment of mice with KH-4-43 following EAE induction resulted in stabilized clinical scores and significantly reduced numbers of T cells and innate immune cells in the CNS compared with control mice. Furthermore, KH-4-43 treatment resulted in elevated expression of p21 and cyclin E2 in T cells. These studies support that therapeutic inhibition of CRL4 and/or CRL4-related pathways could be used to treat autoimmune disease.

Evaluating proxies for motion sickness in rodent.

Motions sickness (MS) occurs when the brain receives conflicting sensory signals from vestibular, visual and proprioceptive systems about a person's ongoing position and/or motion in relation to space. MS is typified by symptoms such as nausea and emesis and implicates complex physiological aspects of sensations and sensorimotor reflexes. Use of animal models has been integral to unraveling the physiological causality of MS. The commonly used rodents (rat and mouse), albeit lacking vomiting reflex, reliably display phenotypic behaviors of pica (eating of non-nutritive substance) and conditioned taste aversion (CTAver) or avoidance (CTAvoi) which utilize neural substrates with pathways that cause gastrointestinal malaise akin to nausea/emesis. As such, rodent pica and CTAver/CTAvoi have been widely used as proxies for nausea/emesis in studies dealing with neural mechanisms of nausea/emesis and MS, as well as for evaluating therapeutics. This review presents the rationale and experimental evidence that support the use of pica and CTAver/CTAvoi as indices for nausea and emesis. Key experimental steps and cautions required when using rodent MS models are also discussed. Finally, future directions are suggested for studying MS with rodent pica and CTAver/CTAvoi models.