Update on the rational use of 90Y-ibritumomab tiuxetan in the treatment of follicular lymphoma

The development of radiolabeled antibodies against CD20 has facilitated targeted treatment of follicular lymphoma (FL). By using 90Y-ibritumomab tiuxetan (Zevalin®), a radionuclide (yttrium-90, linked by the chelator tiuxetan to the antibody ibritumomab) is brought into the vicinity of lymphoma cells. By the so-called cross-fire effect, this beta emitter has the capacity to destroy not only the lymphoma cells having bound the antibody, but also neighboring lymphoma cells. Currently this antibody is licensed in the European Union for use in relapsed or refractory FL. It is anticipated that this drug will also be approved for use as consolidation therapy after successful first-line treatment. Here we first will review the published literature supporting the use of 90Y-ibritumomab tiuxetan in the aforementioned indications and emerging data showing applicability of ibritumomab tiuxetan as sole first-line therapy for FL, as well as in the transplant setting. Possible strategies of incorporating ibritumomab tiuxetan into the treatment algorithm of FL are discussed

Holographic two-point functions for 4d log-gravity

We compute holographic one- and two-point functions of critical higher-curvature gravity in four dimensions. The two most important operators are the stress tensor and its logarithmic partner, sourced by ordinary massless and by logarithmic non-normalisable gravitons, respectively. In addition, the logarithmic gravitons source two ordinary operators, one with spin-one and one with spin-zero. The one-point function of the stress tensor vanishes for all Einstein solutions, but has a non-zero contribution from logarithmic gravitons. The two-point functions of all operators match the expectations from a three-dimensional logarithmic conformal field theory.Comment: 35 pages; v2: typos corrected, added reference; v3: shorter introduction, minor changes in the text in section 3, added reference; published versio

Short-cut to new anomalies in gravity duals to logarithmic conformal field theories

Various massive gravity theories in three dimensions are conjecturally dual to logarithmic conformal field theories (LCFTs). We summarise the status of these conjectures. LCFTs are characterised by the values of the central charges and the so-called "new anomalies". We employ a short-cut to calculate these new anomalies in generalised massive gravity and in the recently proposed higher-derivative gravity theories with holographic c-theorem. Both cases permit LCFTs exhibiting intriguing features, like rank three Jordan cells or non-zero central charges. Finally, as an example we discuss in some detail the partially massless version of new massive gravity, a theory with several special properties that we call "partially massless gravity".Comment: 34 pages, 2 figures; v2: added references; v3: Several rewordings in the introduction and section 2, added references. Matches published versio

SLiM CRAB criteria revisited: temporal trends in prognosis of patients with smoldering multiple myeloma who meet the definition of ‘biomarker-defined early multiple myeloma’—a systematic review with meta-analysisResearch in context

Summary: Background: Biomarker-defined patients with smoldering multiple myeloma (SMM) were included in the diagnostic category of multiple myeloma (MM) by the International Myeloma Working Group (IMWG) in 2014. This includes ≥60% bone marrow plasma cells (BMPCs), free light chain ratio (FLCratio) ≥100, and >1 MRI-defined ≥5 mm focal lesion, also called SLiM CRAB MM. We examined whether the risk of progression of SLiM CRAB MM patients to CRAB positive MM described in recent studies differs from that reported in earlier studies published before the introduction of the new diagnostic criteria. Methods: We conducted a systematic review with meta-analysis, and included studies on Embase and PubMed (01/01/2010–01/11/2022), selecting studies with digitizable progression curves. Inconsistent studies were excluded. We created forest plots using random effects models from digitized and published data and Kaplan–Meier curves. Main outcomes were median time to progression (TTP), 2-year progression risk, and odds ratios (ORs) comparing 2-year progression risks. Findings: Our meta-analysis including 11 studies with 3482 patients found an approximately 3-fold longer TTP and 50% lower 2-year progression risk of SliM CRAB MM patients in recent (published after 2014) compared with earlier studies. Median TTP in patients with ≥60% BMPCs was 30.31 months [18.71–62.93] in recent compared with 9.20 months [6.02–15.56] in earlier studies; the 2-year progression risk was 45.45% [20.12–62.75] compared with 86.21% [65.74–94.45] in the respective time periods. In patients with a FLCratio ≥ 100, the median TTP was 48.06 months [40.51–64.91] vs. 15.33 months [9.38–19.10], and the 2-year progression risk was 31.61% [25.30–37.39] vs. 73.00% [62.39–80.62] in recent and earlier studies, respectively. Tests for heterogeneity showed that the two time periods differed significantly in their ORs when comparing patients who met the high-and low risk criteria. No appropriate recent studies on focal lesions have been published. Interpretation: Recent studies show significantly improved prognosis of biomarker-defined MM with ≥60% BMPCs and FLCratio ≥ 100. This warrants careful evaluation for signs of progression before treatment initiation. Funding: Funding was provided by the Austrian Forum against Cancer

Targeting of BMI-1 with PTC-209 shows potent anti-myeloma activity and impairs the tumour microenvironment

Abstract Background The polycomb complex protein BMI-1 (BMI-1) is a putative oncogene reported to be overexpressed in multiple myeloma (MM). Silencing of BMI-1 was shown to impair the growth and survival of MM cells. However, therapeutic agents specifically targeting BMI-1 were not available so far. Here, we investigated PTC-209, a novel small molecule inhibitor of BMI-1, for its activity in MM. Methods BMI-1 expression was analysed in human MM cell lines and primary MM cells by using publically available gene expression profiling (GEP) data. The anti-MM activity of PTC-209 was investigated by viability testing, cell cycle analysis, annexin V and 7-AAD staining, quantification of cleaved poly(ADP-ribose) polymerase (PARP), JC-1 as well as colony formation assays. Deregulation of central myeloma growth and survival genes was studied by quantitative PCR and flow cytometry, respectively. In addition, the impact of PTC-209 on in vitro osteoclast, osteoblast and tube formation was analysed. Results We confirmed overexpression of BMI-1 in MM patients by using publically available GEP datasets. Of note, BMI-1 expression was further increased at relapse which translated into significantly shorter overall survival in relapsed/refractory patients treated with bortezomib or dexamethasone. Treatment with PTC-209 significantly decreased viable cell numbers in human MM cell lines, induced a G1 cell cycle arrest, promoted apoptosis and demonstrated synergistic activity with pomalidomide and carfilzomib. The anti-MM activity of PTC-209 was accompanied by a significant decrease of cyclin D1 (CCND1) and v-myc avian myelocytomatosis viral oncogene homolog (MYC) expression as well as upregulation of cyclin-dependent kinase inhibitor 1A (CDKN1A) and cyclin-dependent kinase inhibitor 1B (CDKN1B). We also observed upregulation of NOXA (up to 3.6 ± 1.2-fold induction, P = 0.009) and subsequent downregulation of myeloid cell leukemia 1 (MCL-1) protein levels, which likely mediates the apoptotic effects of PTC-209. Importantly, the anti-MM activity was upheld in the presence of stromal support or myeloma growth factors insulin-like growth factor 1 (IGF-1) and interleukin 6 (IL-6). In the MM microenvironment, PTC-209 impaired tube formation, impaired osteoclast development and decreased osteoblast formation in a dose-dependent manner (P < 0.01 at 1 μM, respectively). The latter might be attributed to an induction of DKK1 and was reversed by concurrent anti-DKK1 antibody treatment. Conclusions We confirmed overexpression of BMI-1 in MM highlighting its role as an attractive drug target and reveal therapeutic targeting of BMI-1 by PTC-209 as a promising novel therapeutic intervention for MM

Maternal embryonic leucine zipper kinase is a novel target for proliferation associated high-risk myeloma.

Treatment of high-risk patients is a major challenge in multiple myeloma. This is especially true for patients assigned to the gene-expression-profiling defined proliferation subgroup. Although recent efforts have identified some key players of proliferative myeloma, genetic interactions and players that can be targeted with clinically effective drugs have to be identified to overcome the poor prognosis of these patients. We therefore examined maternal embryonic leucine zipper kinase (MELK) for its implications in hyper-proliferative myeloma and analysed the activity of the MELK inhibitor OTSSP167 in vitro and in vivo. MELK was found to be significantly overexpressed in the proliferative subgroup of myeloma. This finding translated into poor overall survival in patients with high vs. low MELK expression. Enrichment analysis of upregulated genes in myeloma cells of MELKhigh patients confirmed the strong implications in myeloma cell proliferation. Targeting of MELK with OTSSP167 impaired the growth and survival of myeloma cells, thereby affecting central survival factors such as MCL-1 and IRF4. This activity was also observed in the 5TGM.1 murine model of myeloma. OTSSP167 reduced bone marrow infiltration and serum paraprotein levels in a dose-dependent manner. In addition, we revealed a strong link between MELK and other proliferation associated high-risk genes (PLK-1, EZH2, FOXM1, DEPDC1) and MELK inhibition also impaired the expression of those genes. We therefore conclude that MELK is an essential component of a proliferative gene signature and that pharmacological inhibition of MELK represents an attractive novel approach to overcome the poor prognosis of high-risk patients with a proliferative expression pattern

Patterns of somatic mutations in VH genes reveal pathways of clonal transformation from MGUS to multiple myeloma

Monoclonal gammopathy of undetermined significance (MGUS) can transform to multiple myeloma (MM). In myeloma, mutated VH genes with sequence homogeneity reveal a postfollicular origin. Previously, some MGUS cases showed mutated VH genes with intraclonal variation, indicating an earlier stage of arrest. We investigated progression from 2 of 2 MGUS to MM, in which VH genes confirmed clonal evolution. In one MGUS case, intraclonal heterogeneity was evident, and transformation to myeloma occurred rapidly with apparent homogeneity in the emergent clone. However, residual MGUS-derived sequences were detectable at this time. Heterogeneity in MGUS does not associate with benign disease, but it indicates an origin from a tumorigenic cell, most likely surface immunoglobulin+, undergoing somatic mutation. The remaining case displayed intraclonal homogeneity at the MGUS stage, conceivably resulting from a self-cloning outgrowth from MGUS with heterogeneity. Transformation can occur at either MGUS stage, but it involves a single cell in which somatic mutation is then silent