Anti-spike antibody response to the COVID vaccine in lymphoma patients.

Patients with hematologic malignancies have poor outcomes from COVID infection and are less likely to mount an antibody response after COVID infection. This is a retrospective study of adult lymphoma patients who received the COVID vaccine between 12/1/2020 and 11/30/2021. The primary endpoint was a positive anti-COVID spike protein antibody level following the primary COVID vaccination series. The primary vaccination series was defined as 2 doses of the COVID mRNA vaccines or 1 dose of the COVID adenovirus vaccine. Subgroups were compared using Fisher's exact test, and unadjusted and adjusted logistic regression models were used for univariate and multivariate analyses. A total of 243 patients were included in this study; 72 patients (30%) with indolent lymphomas; 56 patients (23%) with Burkitt's, diffuse large B-cell lymphoma (DLBCL), and primary mediastinal B-cell lymphoma (PMBL) combined; 55 patients (22%) with chronic lymphocytic leukemia or small lymphocytic lymphoma (CLL/SLL); 44 patients (18%) with Hodgkin and T-cell lymphomas (HL/TCL) combined; 12 patients (5%) with mantle cell lymphoma; and 4 patients (2%) with other lymphoma types. One-hundred fifty-eight patients (65%) developed anti-COVID spike protein antibodies after completing the primary COVID vaccination series. Thirty-eight of 46 (83%) patients who received an additional primary shot and had resultant levels produced anti-COVID spike protein antibodies. When compared to other lymphoma types, patients with CLL/SLL had a numerically lower seroconversion rate of 51% following the primary vaccination series whereas patients with HL/TCL appeared to have a robust antibody response with a seropositivity rate of 77% (p = 0.04). Lymphoma patients are capable of mounting a humoral response to the COVID vaccines. Further studies are required to confirm our findings, including whether T-cell immunity would be of clinical relevance in this patient population.

Improved Survival of Lymphoma Patients with COVID-19 in the Modern Treatment and Vaccination Era.

Lymphoma patients are at greater risk of severe consequences from COVID-19 infection, yet most reports of COVID-19-associated outcomes were published before the advent of COVID-19 vaccinations and monoclonal antibodies (mAbs). In this retrospective study, we report the real-world outcomes of 68 lymphoma or CLL patients who developed COVID-19 infection during the omicron surge in the US. We found that 34% of patients were hospitalized as a result of COVID-19 infection. The death rate due to COVID-19 was 9% (6/68) in the overall population and 26% (6/23) in hospitalized patients. During the preintervention COVID-19 era, the mortality rate reported in cancer patients was 34%, which increased to 60.2% in hospitalized patients. Thus, the death rates in our study were much lower when compared to those in cancer patients earlier in the pandemic, and may be attributed to modern interventions. In our study, 60% (18/30) of patients with serology data available did not develop anti-COVID-19 spike protein antibodies following vaccination. Most patients (74%, 17/23) who were hospitalized due to COVID-19 infection did not receive COVID-19 mAb treatment. Our results pointed to the importance of humoral immunity and the protective effect of COVID-19 mAbs in improving outcomes in lymphoma patients.

Phase I/II trial of pimasertib plus gemcitabine in patients with metastatic pancreatic cancer.

The selective MEK1/2 inhibitor pimasertib has shown anti-tumour activity in a pancreatic tumour model. This phase I/II, two-part trial was conducted in patients with metastatic pancreatic adenocarcinoma (mPaCa) (NCT01016483). In the phase I part, oral pimasertib was given once daily discontinuously (5 days on/2 days off treatment) or twice daily continuously (n = 53) combined with weekly gemcitabine (1,000 mg/m2 ) in 28-day cycles to identify the recommended phase II dose (RP2D) of pimasertib. In the phase II part, patients were randomised to pimasertib (RP2D) or placebo plus weekly gemcitabine (n = 88) to investigate progression-free survival (PFS), overall survival (OS) and safety. The RP2D was determined to be 60 mg BID. PFS and OS outcomes did not indicate any treatment benefit for pimasertib over placebo in combination with gemcitabine (median PFS 3.7 and 2.8 months, respectively, HR = 0.91, 95% CI: 0.58-1.42: median OS 7.3 vs. 7.6 months, respectively). KRAS status did not influence PFS or OS. The incidence of grade ≥3 adverse events was 91.1% and 85.7% for pimasertib/gemcitabine and placebo/gemcitabine respectively, but there was a higher incidence of ocular events with pimasertib/gemcitabine (28.9% vs. 4.8% for placebo/gemcitabine). In conclusion, no clinical benefit was observed with first-line pimasertib plus gemcitabine compared with gemcitabine alone in patients with mPaCa.

Trends in high-throughput and functional neuroimaging in Caenorhabditis elegans.

The nervous system of Caenorhabditis elegans is an important model system for understanding the development and function of larger, more complex nervous systems. It is prized for its ease of handling, rapid life cycle, and stereotyped, well-cataloged development, with the development of all 302 neurons mapped all the way from zygote to adult. The combination of easy genetic manipulation and optical transparency of the worm allows for the direct imaging of its interior with fluorescent microscopy, without physically compromising the normal physiology of the animal itself. By expressing fluorescent markers, biologists study many developmental and cell biology questions in vivo; by expressing genetically encoded fluorescent calcium indicators within neurons, it is also possible to monitor their dynamic activity, answering questions about the structure and function of neural microcircuitry in the worm. However, to successfully image the worm it is necessary to overcome a number of experimental challenges. It is necessary to hold worms within the field of view, collect images efficiently and rapidly, and robustly analyze the data obtained. In recent years, a trend has developed toward imaging a large number of worms or neurons simultaneously, directly exploiting the unique properties of C. elegans to acquire data on a scale, which is not possible in other organisms. Doing this has required the development of new experimental tools, techniques, and data analytic approaches, all of which come together to open new perspectives on the field of neurobiology in C. elegans, and neuroscience in general. WIREs Syst Biol Med 2017, 9:e1376. doi: 10.1002/wsbm.1376 For further resources related to this article, please visit the WIREs website.

Phase I trial of MEK 1/2 inhibitor pimasertib combined with mTOR inhibitor temsirolimus in patients with advanced solid tumors.

Background Dual inhibition of activated MAPK and mTOR signaling pathways may enhance the antitumor efficacy of the MEK 1/2 inhibitor pimasertib and the mTOR inhibitor temsirolimus given in combination. Methods In this phase I study, patients with refractory advanced solid tumors (NCT01378377) received once-weekly temsirolimus plus once-daily oral pimasertib in 21-day cycles in a modified 3 + 3 dose-escalation design. The maximum tolerated dose (MTD) and recommended phase 2 dose (RP2D) of pimasertib in combination with temsirolimus, safety and pharmacokinetics (PK) were investigated. Results Of 33 patients evaluated, all experienced ≥1 treatment-emergent adverse event (TEAE) and 31 had treatment-related TEAEs, most frequently stomatitis and thrombocytopenia. TEAEs were reversible. No deaths were attributed to treatment. Nine patients had dose-limiting toxicities (stomatitis, thrombocytopenia, serum creatinine phosphokinase increase, visual impairment) and the MTD was determined as 45 mg/day pimasertib plus 25 mg/week temsirolimus. However, due to overlapping toxicities no further investigations were performed and the RP2D was not defined. PK profiles of both agents were not adversely affected. Seventeen patients (17/26 patients) had a best response of stable disease; five had stable disease lasting >12 weeks. Conclusions The RP2D was not defined and the pimasertib plus temsirolimus combination investigated did not warrant further study.

Autoinhibition of a Neuronal Kinesin UNC-104/KIF1A Regulates the Size and Density of Synapses.

Kinesin motor proteins transport intracellular cargoes throughout cells by hydrolyzing ATP and moving along microtubule tracks. Intramolecular autoinhibitory interactions have been shown for several kinesins in vitro; however, the physiological significance of autoinhibition remains poorly understood. Here, we identified four mutations in the stalk region and motor domain of the synaptic vesicle (SV) kinesin UNC-104/KIF1A that specifically disrupt autoinhibition. These mutations augment both microtubule and cargo vesicle binding in vitro. In vivo, these mutations cause excessive activation of UNC-104, leading to decreased synaptic density, smaller synapses, and ectopic localization of SVs in the dendrite. We also show that the SV-bound small GTPase ARL-8 activates UNC-104 by unlocking the autoinhibition. These results demonstrate that the autoinhibitory mechanism is used to regulate the distribution of transport cargoes and is important for synaptogenesis in vivo.

An integrated platform for large-scale data collection and precise perturbation of live Drosophila embryos.

Understanding the fundamental principles governing embryogenesis is a key goal of developmental biology. Direct observation of embryogenesis via in vivo live imaging is vital to understanding embryogenesis; yet, tedious sample preparation makes it difficult to acquire large-scale imaging data that is often required to overcome experimental and biological noises for quantitative studies. Furthermore, it is often difficult, and sometimes impossible, to incorporate environmental perturbation for understanding developmental responses to external stimuli. To address this issue, we have developed a method for high-throughput imaging of live embryos, delivering precise environmental perturbations, and unbiased data extraction. This platform includes an optimized microfluidic device specifically for live embryos and also for precise perturbations in the microenvironment of the developing embryos. In addition, we developed software for simple, yet accurate, automated segmentation of fluorescent images, and automated data extraction. Using a quantitative assessment we find that embryos develop normally within the microfluidic device. Finally, we show an application of the high-throughput assay for monitoring developmental responses to external stimuli: anoxia-induced developmental arrest in Drosophila embryos. With slight modifications, the method developed in this work can be applied to many other models of development and other stimulus-response behaviors during development.

Behavioral relevance helps untangle natural vocal categories in a specific subset of core auditory cortical pyramidal neurons.

Sound categorization is essential for auditory behaviors like acoustic communication, but its genesis within the auditory pathway is not well understood-especially for learned natural categories like vocalizations, which often share overlapping acoustic features that must be distinguished (e.g., speech). We use electrophysiological mapping and single-unit recordings in mice to investigate how representations of natural vocal categories within core auditory cortex are modulated when one category acquires enhanced behavioral relevance. Taking advantage of a maternal mouse model of acoustic communication, we found no long-term auditory cortical map expansion to represent a behaviorally relevant pup vocalization category-contrary to expectations from the cortical plasticity literature on conditioning with pure tones. Instead, we observed plasticity that improved the separation between acoustically similar pup and adult vocalization categories among a physiologically defined subset of late-onset, putative pyramidal neurons, but not among putative interneurons. Additionally, a larger proportion of these putative pyramidal neurons in maternal animals compared with nonmaternal animals responded to the individual pup call exemplars having combinations of acoustic features most typical of that category. Together, these data suggest that higher-order representations of acoustic categories arise from a subset of core auditory cortical pyramidal neurons that become biased toward the combination of acoustic features statistically predictive of membership to a behaviorally relevant sound category.

The interaction of CRM1 and the nuclear pore protein Tpr.

While much has been devoted to the study of transport mechanisms through the nuclear pore complex (NPC), the specifics of interactions and binding between export transport receptors and the NPC periphery have remained elusive. Recent work has demonstrated a binding interaction between the exportin CRM1 and the unstructured carboxylic tail of Tpr, on the nuclear basket. Strong evidence suggests that this interaction is vital to the functions of CRM1. Using molecular dynamics simulations and a newly refined method for determining binding regions, we have identified nine candidate binding sites on CRM1 for C-Tpr. These include two adjacent to RanGTP--from which one is blocked in the absence of RanGTP--and three next to the binding region of the cargo Snurportin. We report two additional interaction sites between C-Tpr and Snurportin, suggesting a possible role for Tpr import into the nucleus. Using bioinformatics tools we have conducted conservation analysis and functional residue prediction investigations to identify which parts of the obtained binding sites are inherently more important and should be highlighted. Also, a novel measure based on the ratio of available solvent accessible surface (RASAS) is proposed for monitoring the ligand/receptor binding process.

An online bioinformatics tool predicts zinc finger and TALE nuclease off-target cleavage.

Although engineered nucleases can efficiently cleave intracellular DNA at desired target sites, major concerns remain on potential 'off-target' cleavage that may occur throughout the genome. We developed an online tool: predicted report of genome-wide nuclease off-target sites (PROGNOS) that effectively identifies off-target sites. The initial bioinformatics algorithms in PROGNOS were validated by predicting 44 of 65 previously confirmed off-target sites, and by uncovering a new off-target site for the extensively studied zinc finger nucleases (ZFNs) targeting C-C chemokine receptor type 5. Using PROGNOS, we rapidly interrogated 128 potential off-target sites for newly designed transcription activator-like effector nucleases containing either Asn-Asn (NN) or Asn-Lys (NK) repeat variable di-residues (RVDs) and 3- and 4-finger ZFNs, and validated 13 bona fide off-target sites for these nucleases by DNA sequencing. The PROGNOS algorithms were further refined by incorporating additional features of nuclease-DNA interactions and the newly confirmed off-target sites into the training set, which increased the percentage of bona fide off-target sites found within the top PROGNOS rankings. By identifying potential off-target sites in silico, PROGNOS allows the selection of more specific target sites and aids the identification of bona fide off-target sites, significantly facilitating the design of engineered nucleases for genome editing applications.

An open-label, single-arm, phase 2 trial of the Polo-like kinase inhibitor volasertib (BI 6727) in patients with locally advanced or metastatic urothelial cancer.

BACKGROUND: Polo-like kinases (Plks) control multiple steps during the cell cycle, and Plk1 is overexpressed in urothelial cancer (UC). Volasertib (BI 6727), a Plk inhibitor, has demonstrated antitumor activity in several malignancies, including UC. In this phase 2 trial, the authors investigated volasertib as a second-line treatment in advanced/metastatic UC. METHODS: Patients who progressed within 2 years of 1 prior chemotherapy regimen received 300 mg volasertib on day 1 every 3 weeks. The dose was escalated to 350 mg in cycle 2 if volasertib was tolerated in cycle 1. The primary endpoint was tumor response, which was assessed every 6 weeks; secondary endpoints were progression-free survival, overall survival, duration of response, safety, and pharmacokinetics. RESULTS: Fifty patients were enrolled, and the median patient age was 68.5 years (range, 52-83 years). All patients had received prior platinum, 94% of patients had relapsed ≤2 years after prior therapy, 36% had liver metastases, and 54% had lung metastases. The median number of treatment cycles was 2 (range, 1-27 treatment cycles), and 23 patients were dose escalated at cycle 2. Seven patients (14%) had a partial response, 13 (26%) had stable disease, and 30 (60%) progressed within 6 weeks. The median response duration was 41 weeks (range, 29.1-77.3 weeks). The median progression-free survival was 1.4 months, and the median overall survival was 8.5 months. The most frequent grade 3 and 4 adverse events were neutropenia (28%), thrombocytopenia (20%), and anemia (16%). No cumulative toxicity was observed. CONCLUSIONS: Volasertib as second-line treatment for advanced/metastatic UC had an acceptable safety profile but demonstrated insufficient antitumor activity for further evaluation as a monotherapy.