Deletion of chromosomal region 8p21 confers resistance to Bortezomib and is associated with upregulated Decoy trail receptor expression in patients with multiple myeloma

Loss of the chromosomal region 8p21 negatively effects survival in patients with multiple myeloma (MM) that undergo autologous stem cell transplantation (ASCT). In this study, we aimed to identify the immunological and molecular consequences of del(8)(p21) with regards to treatment response and bortezomib resistance. In patients receiving bortezomib as a single first line agent without any high-dose therapy, we have observed that patients with del(8)(p21) responded poorly to bortezomib with 50% showing no response while patients without the deletion had a response rate of 90%. In vitro analysis revealed a higher resistance to bortezomib possibly due to an altered gene expression profile caused by del(8)(p21) including genes such as TRAIL-R4, CCDC25, RHOBTB2, PTK2B, SCARA3, MYC, BCL2 and TP53. Furthermore, while bortezomib sensitized MM cells without del(8)(p21) to TRAIL/APO2L mediated apoptosis, in cells with del(8)(p21) bortezomib failed to upregulate the pro-apoptotic death receptors TRAIL-R1 and TRAIL-R2 which are located on the 8p21 region. Also expressing higher levels of the decoy death receptor TRAIL-R4, these cells were largely resistant to TRAIL/APO2L mediated apoptosis. Corroborating the clinical outcome of the patients, our data provides a potential explanation regarding the poor response of MM patients with del(8)(p21) to bortezomib treatment. Furthermore, our clinical analysis suggests that including immunomodulatory agents such as Lenalidomide in the treatment regimen may help to overcome this negative effect, providing an alternative consideration in treatment planning of MM patients with del(8)(p21)

Natural killer cell based therapies targeting cancer: Possible strategies to gain and sustain anti-tumor activity

Natural killer (NK) cells were discovered 40 years ago, by their ability to recognize and kill tumor cells without the requirement of prior antigen exposure. Since then NK cells have been seen as promising agents for cell-based cancer therapies. However, NK cells represent only a minor fraction of the human lymphocyte population. Their skewed phenotype and impaired functionality during cancer progression necessitates the development of clinical protocols to activate and expand to high numbers ex vivo to be able to infuse sufficient numbers of functional NK cells to the cancer patients. Initial NK cell-based clinical trials suggested that NK cell-infusion is safe and feasible with almost no NK cell-related toxicity, including graft-versus-host disease (GvHD). Complete remission and increased disease free survival is shown in a small number of patients with hematological malignances. Furthermore, successful adoptive NK cell based therapies from haploidentical donors have been demonstrated. Disappointingly, only limited anti-tumor effects have been demonstrated following NK cell infusion in patients with solid tumors. While NK cells have great potential in targeting tumor cells, the efficiency of NK cell functions in the tumor microenvironment is yet unclear. The failure of immune surveillance may in part be due to sustained immunological pressure on tumor cells resulting in the development of tumor escape variants that are invisible to the immune system. Alternatively, this could be due to the complex network of immune suppressive compartments in the tumor microenvironment, including myeloid-derived suppressor cells, tumor associated macrophages, and regulatory T cells. Although the negative effect of the tumor microenvironment on NK cells can be transiently reverted by ex vivo-expansion and long-term activation, the abovementioned NK cell/tumor microenvironment interactions upon reinfusion are not fully elucidated. Within this context, genetic modification of NK cells may provide new possibilities for developing effective cancer immunotherapies by improving NK cell responses and making them less susceptible to the tumor microenvironment.Within this review we will discuss clinical trials using NK cells with a specific reflection on novel potential strategies, such as genetic modification of NK cells and complementary therapies aimed at improving the clinical outcome of NK cell-based immune therapies

Characterization of zika virus infection of human fetal cardiac mesenchymal stromal cells.

Zika virus (ZIKV) is a single-stranded RNA virus belonging to the family Flaviviridae. ZIKV predominantly enters cells using the TAM-family protein tyrosine kinase receptor AXL, which is expressed on a range of cell types, including neural progenitor cells, keratinocytes, dendritic cells, and osteoblasts. ZIKV infections have been associated with fetal brain damage, which prompted the World Health Organization to declare a public health emergency in 2016. ZIKV infection has also been linked to birth defects in other organs. Several studies have reported congenital heart defects (CHD) in ZIKV infected infants and cardiovascular complications in adults infected with ZIKV. To develop a better understanding of potential causes for these pathologies at a cellular level, we characterized ZIKV infection of human fetal cardiac mesenchymal stromal cells (fcMSCs), a cell type that is known to contribute to both embryological development as well as adult cardiac physiology. Total RNA, supernatants, and/or cells were collected at various time points post-infection to evaluate ZIKV replication, cell death, and antiviral responses. We found that ZIKV productively infected fcMSCs with peak (~70%) viral mRNA detected at 48 h. Use of an antibody blocking the AXL receptor decreased ZIKV infection (by ~50%), indicating that the receptor is responsible to a large extent for viral entry into the cell. ZIKV also altered protein expression of several mesenchymal cell markers, which suggests that ZIKV could affect fcMSCs' differentiation process. Gene expression analysis of fcMSCs exposed to ZIKV at 6, 12, and 24 h post-infection revealed up-regulation of genes/pathways associated with interferon-stimulated antiviral responses. Stimulation of TLR3 (using poly I:C) or TLR7 (using Imiquimod) prior to ZIKV infection suppressed viral replication in a dose-dependent manner. Overall, fcMSCs can be a target for ZIKV infection, potentially resulting in CHD during embryological development and/or cardiovascular issues in ZIKV infected adults

Correction: Characterization of zika virus infection of human fetal cardiac mesenchymal stromal cells.

[This corrects the article DOI: 10.1371/journal.pone.0239238.]

Boosting Natural Killer Cell Therapies in Glioblastoma Multiforme Using Supramolecular Cationic Inhibitors of Heat Shock Protein 90

Allogeneic natural killer (aNK) cell adoptive therapy has the potential to dramatically impact clinical outcomes of glioblastoma multiforme (GBM). However, in order to exert therapeutic activity, NK cells require tumor expression of ligands for activating receptors, such as MHC Class I peptide A/B (MICA/B) and ULBPs. Here, we describe the use of a blood–brain barrier (BBB) permissive supramolecular cationic drug vehicle comprising an inhibitor of the chaperone heat shock protein 90 (Hsp90), which sustains a cytotoxic effect on GBM cells, boosts the expression of MICA/B and ULBPs on the residual population, and augments the activity of clinical-grade aNK cells (GTA002). First, we identify Hsp90 mRNA transcription and gain of function as significantly upregulated in GBM compared to other central nervous system tumors. Through a rational chemical design, we optimize a radicicol supramolecular prodrug containing cationic excipients, SCI-101, which displays &amp;gt;2-fold increase in relative BBB penetration compared to less cationic formulations in organoids, in vitro. Using 2D and 3D biological models, we confirm SCI-101 sustains GBM cytotoxicity 72 h after drug removal and induces cell surface MICA/B protein and ULBP mRNA up to 200% in residual tumor cells compared to the naked drug alone without augmenting the shedding of MICA/B, in vitro. Finally, we generate and test the sequential administration of SCI-101 with a clinical aNK cell therapy, GTA002, differentiated and expanded from healthy umbilical cord blood CD34+ hematopoietic stem cells. Using a longitudinal in vitro model, we demonstrate &amp;gt;350% relative cell killing is achieved in SCI-101–treated cell lines compared to vehicle controls. In summary, these data provide a first-of-its-kind BBB-penetrating, long-acting inhibitor of Hsp90 with monotherapy efficacy, which improves response to aNK cells and thus may rapidly alter the treatment paradigm for patients with GBM.</jats:p

Quantitative RT-PCR analysis of gene expression in MM patients with or without del(8)(p21).

<p>TLDA cards were used to analyze mRNA levels in patients with (n = 19) and without (n = 6) del(8)(p21). For the analysis, GAPDH and ACTB genes were used as endogenous controls while RNA samples from K562 and U266 cell lines were used as calibrators. (*p<0.05, unpaired t test) (A) The mRNA level relative expression of TRAIL receptors in patients with and without the deletion. TRAIL-R1,-R2 and–R3 did not show any change while TRAIL-R4 was expressed at significantly higher levels in patients carrying the deletion. (B) Genes on or near 8p21 <b>(C)</b> other analyzed genes located elsewhere in the chromosome that show at least two-fold differential expression in MM cells with the deletion. Depicted are the gene expression levels in MM cells carrying the deletion, normalized to samples without the deletion.</p

Additional file 3 of Natural killer cells in clinical development as non-engineered, engineered, and combination therapies

Additional file 3: Table S3. List of clinical trials with non-engineered combination NK cell therapies. N = 62 clinical trials (Phase I, II, or I/II) evaluating the infusion of non-engineered allogeneic NK cells in combination with other agents were registered on ClinicalTrials.gov until 31–12–2021. Studies are sorted by types of combination therapy (NK cell priming agents, Adoptive cell therapy, Antibodies, Co-stimulation, Multiple combinations, Molecular inhibitors and NK cell engagers). Details of the combination approach and the clinical trial design and outcome (when available) are presented. Trial status is updated to August 2022

Additional file 4 of Natural killer cells in clinical development as non-engineered, engineered, and combination therapies

Additional file 4: Table S4. List of clinical trials with engineered combination NK cell therapies. N = 34 clinical trials (Phase I, II, or I/II) evaluating the infusion of engineered allogeneic NK cells in combination with other agents were registered on ClinicalTrials.gov until 31–12–2021. Studies are sorted by types of combination therapy (Antibodies, Multiple combinations). Details of the combination approach and the clinical trial design and outcome (when available) are presented. Trial status is updated to August 2022

Patients with del(8)(p21) fail to upregulate pro-apoptotic TRAIL receptor expression upon bortezomib treatment.

<p>Relative expression of TRAIL receptors of 5 MM patients with del(8)(p21) and 7 MM patients without deletion is determined by flow cytometry. Cell surface Expression levels are normalized to corresponding isotype controls. <b>(A)</b> TRAIL-R1, <b>(B)</b> TRAIL-R2, <b>(C)</b> TRAIL-R3, <b>(D)</b> TRAIL-R4. Effect of bortezomib treatment on TRAIL receptor expression is analyzed by paired t-test.</p