We designed, synthesized, and characterized a novel nucleoside analog, (1
,3
,5
)-3-(2-amino-6-oxo-1,6-dihydro-9H-purin-9-yl)-5-hydroxy-1-(hydroxymethyl)-2-methylene-cyclopentanecarbonitrile, or ...4'-cyano-methylenecarbocyclic-2'-deoxyguanosine (CMCdG), and evaluated its anti-hepatitis B virus (anti-HBV) activity, safety, and related features. CMCdG's
activity was determined using quantitative PCR and Southern blotting assays, and its cytotoxicity was determined with a 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide assay, while its
activity and safety were determined in human liver-chimeric mice infected with wild-type HBV genotype Ce (HBV
) and an entecavir (ETV)-resistant HBV variant containing the amino acid substitutions L180M, S202G, and M204V (HBV
). CMCdG potently inhibited HBV production in HepG2.2.15 cells (50% inhibitory concentration IC
, ∼30 nM) and HBV
plasmid-transfected Huh7 cells (IC
, 206 nM) and efficiently suppressed ETV-resistant HBV
(IC
, 2,657 nM), while it showed no or little cytotoxicity (50% cytotoxic concentration, >500 μM in most hepatocytic cells examined). Two-week peroral administration of CMCdG (1 mg/kg of body weight/day once a day q.d.) to HBV
-infected human liver-chimeric mice reduced the level of viremia by ∼2 logs. CMCdG also reduced the level of HBV
viremia by ∼1 log in HBV
-infected human liver-chimeric mice, while ETV (1 mg/kg/day q.d.) completely failed to reduce the viremia. None of the CMCdG-treated mice had significant drug-related changes in body weights or serum human albumin levels. Structural analyses using homology modeling, semiempirical quantum methods, and molecular dynamics revealed that although ETV triphosphate (TP) forms good van der Waals contacts with L180 and M204 of HBV
reverse transcriptase (RT), its contacts with the M180 substitution are totally lost in the HBV
RT complex. However, CMCdG-TP retains good contacts with both the HBV
RT and HBV
RT complexes. The present data warrant further studies toward the development of CMCdG as a potential therapeutic for patients infected with drug-resistant HBV and shed light on the further development of more potent and safer anti-HBV agents.
Adrenocortical carcinoma (ACC) is a rare malignancy with an overall unfavorable prognosis. Clinicians treating patients with ACC have noted accelerated growth in metastatic liver lesions that ...requires rapid intervention compared to other metastatic locations. This study measured and compared the growth rates of metastatic ACC lesions in the lungs, liver, and lymph nodes using volumetric segmentation. A total of 12 patients with metastatic ACC (six male; six female) were selected based on their medical history. Computer tomography (CT) exams were retrospectively reviewed and a sampling of ≤5 metastatic lesions per organ were selected for evaluation. Lesions in the liver, lung, and lymph nodes were measured and evaluated by volumetric segmentation. Statistical analyses were performed to compare the volumetric growth rates of the lesions in each organ system. In this cohort, 5/12 had liver lesions, 7/12 had lung lesions, and 5/12 had lymph node lesions. A total of 92 lesions were evaluated and segmented for lesion volumetry. The volume doubling time per organ system was 27 days in the liver, 90 days in the lungs, and 95 days in the lymph nodes. In this series of 12 patients with metastatic ACC, liver lesions showed a faster growth rate than lung or lymph node lesions.
Neutrophils are the most abundant leukocyte and play a critical role in the initial response to an Ag. Recently, their ability to contribute to adaptive immunity has been highlighted. We evaluated ...the ability of neutrophils from blood to contribute to the adaptive immune response in a preclinical rhesus macaque SIV vaccine trial. Replication-competent adenovirus-SIV recombinants induced neutrophil activation, B cell help markers, and enhanced ability to generate reactive oxygen species. Boosting with SIV vaccines (adjuvant together with ALVAC or DNA plus envelope protein) elicited significant neutrophil responses. Serum cytokine and chemokine levels induced correlated with the frequency of neutrophil subsets expressing IL-21, myeloperoxidase, and CD64. Post-SIV infection, neutrophils exhibited dysfunction, both phenotypically and functionally. B cells from protected and infected macaques cocultured with autologous polymorphonuclear cells, consisting primarily of neutrophils, were activated, underwent class switching, and produced Abs. This B cell help was not aided by addition of IL-10 and was largely contact dependent. Numerous genes associated with inflammation, Ab production, and chemotaxis were upregulated in the cocultured B cells. We conclude that immune stimulation by vaccination or antigenic exposure imparts a greater ability of neutrophils to contribute to the adaptive immune response. Harnessing this granulocytic response has the potential to improve vaccine efficacy.
Fracture Risk in Pediatric Patients With MEN2B Li, Iris; Hartley, Iris R; Klubo-Gwiedzdzinska, Joanna ...
The journal of clinical endocrinology and metabolism,
11/2022, Letnik:
107, Številka:
12
Journal Article
Recenzirano
Odprti dostop
The skeletal phenotype of patients with MEN2B has been described but fracture risk in these patients has not yet been evaluated.
This work aims to better delineate fracture risk in patients with ...multiple endocrine neoplasia type 2B (MEN2B).
This case series with chart review was conducted at the National Institutes of Health, Pediatric Oncology Branch. A total of 48 patients with MEN2B were identified, with an age range of 5 to 36 years, median of 19; 24 of 48 (50%) patients were female. Medical records, demographic information, available imaging, and laboratory results were reviewed. History up to age 19 was included in the statistical analyses.
Of the 48 patients with MEN2B, 20 patients experienced at least one fracture. The majority (n = 18) experienced their first fracture at or before age 19. The observed frequency of fracture occurrence throughout childhood (0-19 years) was 38%, with very little difference between males and females. This frequency is higher than the 9.47 to 36.1 fractures per 1000 persons per year that has been reported in healthy pediatric cohorts in the United States. Less common sites of fracture including vertebral compression fracture and pelvic fractures were observed in patients with MEN2B.
In this group of patients with MEN2B, there was an increased overall risk of fracture compared to general pediatric cohorts in the United States. Less common sites of fracture were also observed. This suggests a possible effect of an activating RET mutation on bone physiology and warrants further investigation.
•Murine allogeneic anti-CD19 CAR T cells integrated before or early after PTCy for allo-HCT can clear leukemia without added toxicity.•Clinical translation of this approach would combine the activity ...of both CAR T cells and polyclonal alloreactive T cells to reduce relapse.
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Relapse limits the therapeutic efficacy both of chimeric antigen receptor (CAR) T cells and allogeneic hematopoietic cell transplantation (allo-HCT). Patients may undergo these therapies sequentially to prevent or treat relapsed malignancy. However, direct integration of the 2 therapies has been avoided over concerns for potential induction of graft-versus-host disease (GVHD) by allogeneic CAR T cells. We have shown in murine T-cell-replete MHC-haploidentical allo-HCT that suppressive mechanisms induced immediately after posttransplant cyclophosphamide (PTCy), given on days +3/+4, prevent GVHD induction by alloreactive T cells infused as early as day +5. Therefore, we hypothesized that allogeneic CAR T cells given in a similarly integrated manner in our murine MHC-haploidentical allo-HCT model may safely exert antitumor effects. Indeed, allogeneic anti-CD19 CAR T cells given early after (day +5) PTCy or even prior to (day 0) PTCy cleared leukemia without exacerbating the cytokine release syndrome occurring from the MHC-haploidentical allo-HCT or interfering with PTCy-mediated GVHD prevention. Meanwhile, CAR T-cell treatment on day +9 or day +14 was safe but less effective, suggesting a limited therapeutic window. CAR T cells infused before PTCy were not eliminated, but surviving CAR T cells continued to proliferate highly and expand despite PTCy. In comparison with infusion on day +5, CAR T-cell infusion on day 0 demonstrated superior clinical efficacy associated with earlier CAR T-cell expansion, higher phenotypic CAR T-cell activation, less CD4+CD25+Foxp3+ CAR T-cell recovery, and transcriptional changes suggesting increased activation of CD4+ CAR T cells and more cytotoxic CD8+ CAR T cells. This study provides mechanistic insight into PTCy’s impact on graft-versus-tumor immunity and describes novel approaches to integrate CAR T cells and allo-HCT that may compensate for deficiencies of each individual approach.
Little is known about how to optimally sequence allogeneic stem cell transplants (allo-HCT) and CAR T-cell therapy. Using murine models, Patterson et al demonstrate that allo-HCT with posttransplantation cyclophosphamide can be combined effectively with allogeneic CD19 CAR T-cell treatment. The authors highlight that CAR T cells given just before or shortly after cyclophosphamide graft-versus-host disease prophylaxis exert stronger antileukemic effects than CAR T cells administered later, suggesting a strategy to leverage the complementary antileukemic effects of polyclonal alloreactive T cells and antigen-specific CAR T cells.
PurposeBintrafusp alfa is a bifunctional agent consisting of an anti-human PD-L1 antibody linked to two TGFβRII. It is designed to act both as a checkpoint inhibitor and to ‘trap’ TGFβ in the tumor ...microenvironment. Phase I and II clinical studies demonstrated clinical activity in patients with a range of human papillomavirus (HPV)-associated cancers. The purpose of the studies reported here was the interrogation of various aspects of the peripheral immunome in patients with HPV-associated cancers, both prior to and early in the treatment regimen of bintrafusp alfa to better understand the mode of action of the agent and to help define which patients are more likely to benefit from bintrafusp alfa treatment.Patients and methodsThe peripheral immunome of patients (n=65) with HPV+ malignancies was analyzed both prior to treatment with bintrafusp alfa and day 14 post-treatment for levels and changes in (1) 158 different immune cell subsets, (2) multiple plasma soluble factors including analytes reflecting immune stimulatory and inhibitory status, (3) complete blood counts, and in a subset of patients (4) TCR diversity and (5) HPV-specific T-cell responses.ResultsInterrogation of the peripheral immunome prior to bintrafusp alfa treatment revealed several factors that associated with clinical response, including (1) higher levels of sCD27:sCD40L ratios, (2) lower levels of TGFβ1 and 12 additional factors associated with tumor mesenchymalization, and (3) higher CD8+ T cell:MDSC ratios. Analysis at 2 weeks post bintrafusp alfa revealed that eventual clinical responders had fewer increases in IL-8 levels and the neutrophil to lymphocyte ratio, and higher levels of HPV-16 specific CD8+ T cells. This study also provided information concerning differences in the peripheral immunome for patients who were naïve versus refractory to prior checkpoint inhibition therapy. While preliminary, two multivariate models developed predicted clinical benefit with 76%–91% accuracy.ConclusionsThese studies add insight into the mechanism of action of bintrafusp alfa and provide evidence that the interrogation of both cellular and soluble components of the peripheral immunome of patients with HPV-associated malignancies, either prior to or early in the therapeutic regimen, can provide information as to which patients are more likely to benefit with bintrafusp alfa therapy.
iNKT cells are CD1d-restricted T cells recognizing lipid antigens. The prototypic iNKT cell-agonist α-galactosylceramide (α-GalCer) alongside compounds with similar structures induces robust ...proliferation and cytokine production of iNKT cells and protects against cancer
. Monoclonal antibodies (mAbs) that detect CD1d-α-GalCer complexes have provided critical information for understanding of antigen presentation of iNKT cell agonists. Although most iNKT cell agonists with antitumor properties are α-linked glycosphingolipids that can be detected by anti-CD1d-α-GalCer mAbs, β-ManCer, a glycolipid with a β-linkage, induces strong antitumor immunity via mechanisms distinct from those of α-GalCer. In this study, we unexpectedly discovered that anti-CD1d-α-GalCer mAbs directly recognized β-ManCer-CD1d complexes and could inhibit β-ManCer stimulation of iNKT cells. The binding of anti-CD1d-α-GalCer mAb with β-ManCer-CD1d complexes was also confirmed by plasmon resonance and could not be explained by α-anomer contamination. The binding of anti-CD1d-α-GalCer mAb was also observed with CD1d loaded with another β-linked glycosylceramide, β-GalCer (C26:0). Detection with anti-CD1d-α-GalCer mAbs indicates that the interface of the β-ManCer-CD1d complex exposed to the iNKT cell TCR can assume a structure like that of CD1d-α-GalCer, despite its disparate carbohydrate structure. These results suggest that certain β-linked monoglycosylceramides can assume a structural display similar to that of CD1d-α-GalCer and that the data based on anti-CD1d-α-GalCer binding should be interpreted with caution.
Selumetinib was recently approved for the treatment of inoperable symptomatic plexiform neurofibromas (PNs) in children with neurofibromatosis type 1 (NF1). This parallel phase II study determined ...the response rate to selumetinib in children with NF1 PN without clinically significant morbidity.
Children with NF1 and inoperable PNs, which were not yet causing clinically significant morbidity but had the potential to cause symptoms, received selumetinib at 25 mg/m2 orally twice daily (1 cycle = 28 days). Volumetric magnetic resonance imaging analysis and outcome assessments, including patient-reported (PRO), observer-reported, and functional outcome measures were performed every 4 cycles for 2 years, with changes assessed over time. A confirmed partial response (cPR) was defined as PN volume decrease of ≥20% on at least 2 consecutive scans ≥3 months apart.
72% of subjects experienced a cPR on selumetinib. Participants received selumetinib for a median of 41 cycles (min 2, max 67) at data cutoff. Approximately half of the children rated having some target tumor pain at baseline, which significantly decreased by pre-cycle 13. Most objectively measured baseline functions, including visual, motor, bowel/bladder, or airway function were within normal limits and did not clinically or statistically worsen during treatment.
Selumetinib resulted in PN shrinkage in most subjects with NF1 PN without clinically significant morbidity. No new PN-related symptoms developed while on selumetinib, and PRO measures indicated declines in tumor-related pain intensity. This supports that selumetinib treatment may prevent the development of PN-related morbidities, though future prospective studies are needed to confirm these results.
ClinicalTrials.gov NCT01362803.
Immunomodulatory imide drugs (IMiDs) play a crucial role in the treatment landscape across various stages of multiple myeloma. Despite their evident efficacy, some patients may exhibit primary ...resistance to IMiD therapy, and acquired resistance commonly arises over time leading to inevitable relapse. It is critical to develop novel therapeutic options to add to the treatment arsenal to overcome IMiD resistance. We designed, synthesized, and screened a new class of polyfluorinated thalidomide analogs and investigated their anti-cancer, anti-angiogenic, and anti-inflammatory activity using in vitro and ex vivo biological assays. We identified four lead compounds that exhibit potent anti-myeloma, anti-angiogenic, anti-inflammatory properties using three-dimensional tumor spheroid models, in vitro tube formation, and ex vivo human saphenous vein angiogenesis assays, as well as the THP-1 inflammatory assay. Western blot analyses investigating the expression of proteins downstream of cereblon (CRBN) reveal that Gu1215, our primary lead candidate, exerts its activity through a CRBN-independent mechanism. Our findings demonstrate that the lead compound Gu1215 is a promising candidate for further preclinical development to overcome intrinsic and acquired IMiD resistance in multiple myeloma.
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