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Blood Jun 2024T-prolymphocytic leukemia (T-PLL) is a mature T-cell neoplasm associated with marked chemotherapy resistance and continued poor clinical outcomes. Current treatments,...
T-prolymphocytic leukemia (T-PLL) is a mature T-cell neoplasm associated with marked chemotherapy resistance and continued poor clinical outcomes. Current treatments, i.e. the CD52-antibody alemtuzumab, offer transient responses, with relapses being almost inevitable without consolidating allogeneic transplantation. Recent more detailed concepts of T-PLL's pathobiology fostered the identification of actionable vulnerabilities: (i) altered epigenetics, (ii) defective DNA damage responses, (iii) aberrant cell-cycle regulation, and (iv) deregulated pro-survival pathways, including TCR and JAK/STAT signaling. To further develop related pre-clinical therapeutic concepts, we studied inhibitors of (H)DACs, BCL2, CDK, MDM2, and clas-sical cytostatics, utilizing (a) single-agent and combinatorial compound testing in 20 well-characterized and molecularly-profiled primary T-PLL (validated by additional 42 cases), and (b) 2 independent murine models (syngeneic transplants and patient-derived xenografts). Overall, the most efficient/selective single-agents and combinations (in vitro and in mice) in-cluded Cladribine, Romidepsin ((H)DAC), Venetoclax (BCL2), and/or Idasanutlin (MDM2). Cladribine sensitivity correlated with expression of its target RRM2. T-PLL cells revealed low overall apoptotic priming with heterogeneous dependencies on BCL2 proteins. In additional 38 T-cell leukemia/lymphoma lines, TP53 mutations were associated with resistance towards MDM2 inhibitors. P53 of T-PLL cells, predominantly in wild-type configuration, was amenable to MDM2 inhibition, which increased its MDM2-unbound fraction. This facilitated P53 activa-tion and down-stream signals (including enhanced accessibility of target-gene chromatin re-gions), in particular synergy with insults by Cladribine. Our data emphasize the therapeutic potential of pharmacologic strategies to reinstate P53-mediated apoptotic responses. The identified efficacies and their synergies provide an informative background on compound and patient selection for trial designs in T-PLL.
PubMed: 38941598
DOI: 10.1182/blood.2023022884 -
Gastric Cancer : Official Journal of... Jun 2024The contribution of the tumor microenvironment and extracellular matrix to the aggressive biology of Gastric Cancer (GC) has been recently characterized; however, the...
BACKGROUND
The contribution of the tumor microenvironment and extracellular matrix to the aggressive biology of Gastric Cancer (GC) has been recently characterized; however, the role of EMILIN-1 in this context is unknown. EMILIN-1 is an essential structural element for the maintenance of lymphatic vessel (LV) integrity and displays anti-proliferative properties as demonstrated in skin and colon cancer. Given the key role of LVs in GC progression, the aim of this study was to investigate the role of EMILIN-1 in GC mouse models.
METHODS
We used the syngeneic YTN16 cells which were injected subcutaneously and intraperitoneally in genetically modified EMILIN-1 mice. In alternative, carcinogenesis was induced using N-Methyl-N-nitrosourea (MNU). Mouse-derived samples and human biopsies were analyzed by IHC and IF to the possible correlation between EMILIN-1 expression and LV pattern.
RESULTS
Transgenic mice developed tumors earlier compared to WT animals. 20 days post-injection tumors developed in EMILIN-1 mutant mice were larger and displayed a significant increase of lymphangiogenesis. Treatment of transgenic mice with MNU associated with an increased number of tumors, exacerbated aggressive lesions and higher levels of LV abnormalities. A significant correlation between the levels of EMILIN-1 and podoplanin was detected also in human samples, confirming the results obtained with the pre-clinical models.
CONCLUSIONS
This study demonstrates for the first time that loss of EMILIN-1 in GC leads to lymphatic dysfunction and proliferative advantages that sustain tumorigenesis, and assess the use of our animal model as a valuable tool to verify the fate of GC upon loss of EMILIN-1.
PubMed: 38941035
DOI: 10.1007/s10120-024-01528-z -
Small (Weinheim An Der Bergstrasse,... Jun 2024Increased expression of immune check point genes, such as PD-L1, is one of the main reasons for immunosuppression, especially for colon cancer. Development of novel...
Increased expression of immune check point genes, such as PD-L1, is one of the main reasons for immunosuppression, especially for colon cancer. Development of novel therapeutic strategies is of great importance to improve the prognosis. In this study, outer membrane vesicles (OMV) derived from Gram-negative bacteria are engineered to immune checkpoint blockade nanosystem for efficient elicitation of anti-tumor immunity. Briefly, the OMVs are engineered with Lyp1-Traptavidin (S52G, R53D mutant of streptavidin) fusion protein displayed on the surface. The Lyp-1 endows the OMV with the capacity to target tumor tissues, while the Traptavidin ensures easy decoration of biotinylated anti-PD-L1 and biotinylated M6P (mannose 6-phosphate). The simultaneously anchored anti-PD-L1 and M6P (ligand for cation-independent mannose 6-phosphate receptor) on the engineered OMVs coordinately direct the membrane PD-L1 to lysosome for degradation, and thus unleash the anti-tumor immunity. With syngeneic tumor model, the engineered OMVs are confirmed to boost immunity, inhibit cancer growth, and thus prolong survival. Together, A proposed OMV-based modular nanosystem that enables assembly of biotinylated anti-PD-L1 and M6P on the surface for tumor-targeted immune checkpoint blockade.
PubMed: 38934533
DOI: 10.1002/smll.202400770 -
Kidney Research and Clinical Practice Jun 2024The aim of this study is to investigate the specific pathway involved in human leukocyte antigen (HLA) sensitization using single-cell RNA-sequencing analysis and an...
BACKGROUND
The aim of this study is to investigate the specific pathway involved in human leukocyte antigen (HLA) sensitization using single-cell RNA-sequencing analysis and an allo-sensitized mouse model developed with an HLA.A2 transgenic mouse.
METHODS
For sensitization, wild-type C57BL/6 mouse received two skin grafts from C57BL/6-Tg(HLA-A2.1)1Enge/J mouse (allogeneic mouse, ALLO). For syngeneic control (SYN), skin grafts were transferred from C57BL/6 to C57BL/6. We performed single-cell RNA-sequencing analysis on splenocytes isolated from ALLO and SYN and compared the gene expression between them.
RESULTS
We generated 9,190 and 8,890 single-cell transcriptomes from ALLO and SYN, respectively. Five major cell types (B cells, T cells, natural killer cells, macrophages, and neutrophils) and their transcriptome data were annotated according to the representative differentially expressed genes of each cell cluster. The percentage of B cells was higher in ALLO than it was in SYN. Kyoto Encyclopedia of Genes and Genomes enrichment analyses indicated that the highly expressed genes in the B cells from ALLO were mainly associated with antigen processing and presentation pathways, allograft rejection, and the Th17 cell differentiation pathway. Upregulated genes in the T cells of ALLO were involved in the interleukin (IL)-17 signaling pathway. The ratio of Th17 cluster and Treg cluster was increased in the ALLO. On flow cytometry, the percentage of Th17 (IL-17+/CD4+ T) cells was higher and regulatory T cells (FOXP3+/CD4+ T) was lower in the ALLO compared to those in the SYN.
CONCLUSION
Our results indicate that not only the B cell lineage but also the Th17 cells and their cytokine (IL-17) are involved in the sensitization to HLA.
PubMed: 38934039
DOI: 10.23876/j.krcp.23.317 -
Vaccines Jun 2024Therapeutic modified mRNAs are being developed for a broad range of human diseases. However, the impact of potential miscoding of modified mRNAs on self-tolerance...
Therapeutic modified mRNAs are being developed for a broad range of human diseases. However, the impact of potential miscoding of modified mRNAs on self-tolerance remains unknown. Additionally, more studies are needed to explore the effects of nucleoside alkylation on translation. While all six tested modifications are tolerated as substrates by T7 RNA polymerase and inhibited mRNA immunogenicity, the translation efficiency varied significantly depending on the type of modification. In contrast to methylation, ethylation at the N1 position of pseudouridine (Ψ) hindered translation, suggesting that the C5-C1' glycosidic bond alone is not a critical element for high translation. Inhibition of mRNA translation was also observed with 5-methoxyuridine modification. However, this inhibition was partially alleviated through the optimization of mRNA coding sequences. BALB/c mice immunized with syngeneic ψ-modified mRNA encoding for Wilms' tumor antigen-1 (WT1) developed a low but significant level of anti-WT1 IgG antibodies compared to those immunized with either unmodified or N1-methyl ψ-modified mRNA. Overall, the data indicate that adding a simple ethyl group (-CHCH) at the N1 position of ψ has a major negative effect on translation despite its reduced immunogenicity. Additionally, mRNA containing Ψ may alter translation fidelity at certain codons, which could lead to a breakdown of immune tolerance to self-antigens. This concern should be taken into account during gene replacement therapies, although it could benefit mRNA-based vaccines by generating a diverse repertoire of antigens.
PubMed: 38932353
DOI: 10.3390/vaccines12060624 -
Journal For Immunotherapy of Cancer Jun 2024Despite continuous improvements in the new target and construction of chimeric antigen receptor (CAR)-T, relapse remains a significant challenge following CAR-T therapy....
BACKGROUND
Despite continuous improvements in the new target and construction of chimeric antigen receptor (CAR)-T, relapse remains a significant challenge following CAR-T therapy. Tumor microenvironment (TME) strongly correlates with the efficacy of CAR-T therapy. V-domain Ig suppressor of T-cell activation (VISTA), which exerts a multifaceted and controversial role in regulating the TME, acts not only as a ligand on antigen-presenting cells but also functions as a receptor on T cells. However, the characteristics and underlying mechanisms governing endogenous T-cell activation by VISTA, which are pivotal for reshaping the TME, remain incompletely elucidated.
METHODS
The immunocompetent B acute lymphoblastic leukemia (B-ALL), lymphoma, and melanoma murine models were employed to investigate the characteristics of endogenous T cells within the TME following CD19 and hCAIX CAR-T cell therapy, respectively. Furthermore, we examined the role of VISTA controlled by interferon (IFN)-γ signaling in regulating endogenous T-cell activation and functionality in B-ALL mice.
RESULTS
We demonstrated that the administration of CD19 CAR-T or hCAIX CAR-T cell therapy elicited augmented immune responses of endogenous T cells within the TME of B-ALL, lymphoma, and melanoma mice, thereby substantiating the efficacy of CAR-T cell efficacy. However, in the TME lacking IFN-γ signaling, VISTA levels remained elevated, resulting in attenuated cytotoxicity of endogenous T cells and reduced B-ALL recipient survival. Mice treated with CD19 CAR-T cells exhibited increased proportions of endogenous memory T cells during prolonged remission, which possessed the tumor-responsive capabilities to protect against B-ALL re-challenge. Compared with wild-type (WT) CAR-T treated mice, the administration of IFN-γ CAR-T to both WT and IFN-γ recipients resulted in a reduction in the numbers of endogenous CD4 and CD8 effectors, while exhibiting increased populations of naïve-like CD4 T and memory CD8 T cells. VISTA expression consistently remained elevated in resting or memory CD4 T cells, with distinct localization from programmed cell death protein-1 (PD-1) expressing T subsets. Blocking the VISTA signal enhanced dendritic cell-induced proliferation and cytokine production by syngeneic T cells.
CONCLUSION
Our findings confirm that endogenous T-cell activation and functionality are regulated by VISTA, which is associated with the therapeutic efficiency of CAR-T and provides a promising therapeutic strategy for relapse cases in CAR-T therapy.
Topics: Animals; Mice; Interferon-gamma; Immunotherapy, Adoptive; Antigens, CD19; Tumor Microenvironment; T-Lymphocytes; Humans; Cell Line, Tumor; Disease Models, Animal; B7 Antigens; Lymphocyte Activation; Receptors, Chimeric Antigen; Membrane Proteins
PubMed: 38925679
DOI: 10.1136/jitc-2023-008364 -
Cancer Research Jun 2024Two recent papers document that responses to immunotherapy are circadian and peak at the end of resting phase (evening) of mice with syngeneic and genetic models of...
Two recent papers document that responses to immunotherapy are circadian and peak at the end of resting phase (evening) of mice with syngeneic and genetic models of cancers. The circadian effect is attributed to diurnal T cell trafficking through the endothelium on the one hand, and to the circadian expression of PD-L1 on myeloid suppressors on the other. Overall, it appears that tumor immunity as a system, including dendritic cell function, behaves in a circadian manner that is also observed in patients in cancer immunotherapy clinical trials. Importantly, these observations uncover time-of-day as an unforeseen variable for cancer immunotherapy responses. This insight on the immune circadian clock should be further explored to enhance immunotherapy responses in the clinic.
PubMed: 38924465
DOI: 10.1158/0008-5472.CAN-24-2083 -
Cells Jun 2024Serine/threonine kinase AKT isoforms play a well-established role in cell metabolism and growth. Most pancreatic adenocarcinomas (PDACs) harbor activation mutations of...
Serine/threonine kinase AKT isoforms play a well-established role in cell metabolism and growth. Most pancreatic adenocarcinomas (PDACs) harbor activation mutations of KRAS, which activates the PI3K/AKT signaling pathway. However, AKT inhibitors are not effective in the treatment of pancreatic cancer. To better understand the role of AKT signaling in mutant-KRAS pancreatic tumors, this study utilized proteolysis-targeting chimeras (PROTACs) and CRISPR-Cas9-genome editing to investigate AKT proteins. The PROTAC down-regulation of AKT proteins markedly slowed the growth of three pancreatic tumor cell lines harboring mutant KRAS. In contrast, the inhibition of AKT kinase activity alone had very little effect on the growth of these cell lines. The concurrent genetic deletion of all AKT isoforms (AKT1, AKT2, and AKT3) in the KPC (; ; ) pancreatic cancer cell line also dramatically slowed its growth in vitro and when orthotopically implanted in syngeneic mice. Surprisingly, insulin-like growth factor-1 (IGF-1), but not epidermal growth factor (EGF), restored KPC cell growth in serum-deprived conditions, and the IGF-1 growth stimulation effect was AKT-dependent. The RNA-seq analysis of AKT1/2/3-deficient KPC cells suggested that reduced cholesterol synthesis may be responsible for the decreased response to IGF-1 stimulation. These results indicate that the presence of all three AKT isoforms supports pancreatic tumor cell growth, and the pharmacological degradation of AKT proteins may be more effective than AKT catalytic inhibitors for treating pancreatic cancer.
Topics: Proto-Oncogene Proteins c-akt; Pancreatic Neoplasms; Animals; Cell Line, Tumor; Mice; Humans; Down-Regulation; Proto-Oncogene Proteins p21(ras); Mutation; Cell Proliferation; Signal Transduction; Gene Expression Regulation, Neoplastic
PubMed: 38920688
DOI: 10.3390/cells13121061 -
Diseases (Basel, Switzerland) Jun 2024Due to the rich ethnobotanical and growing evidence-based medicine records, the , i.e., the upper parts of the Lady's mantle ( L.), was used for the assessment of...
Due to the rich ethnobotanical and growing evidence-based medicine records, the , i.e., the upper parts of the Lady's mantle ( L.), was used for the assessment of antimelanoma activity. The ethanolic extract of strongly suppressed the viability of B16F1, B16F10, 518A2, and Fem-X cell lines. In contrast to the in vitro study, where the B16F1 cells were more sensitive to the treatment than the more aggressive counterpart B16F10, the results obtained in vivo using the corresponding syngeneic murine model were quite the opposite. The higher sensitivity of B16F10 tumors in vivo may be attributed to a more complex response to the extract compared to one triggered in vitro. In addition, the strong immunosuppressive microenvironment in the B16F1 model is impaired by the treatment, as evidenced by enhanced antigen-presenting potential of dendritic cells, influx and activity of CD4 T and CD8 T lymphocytes, decreased presence of T regulatory lymphocytes, and attenuation of anti-inflammatory cytokine production. All these effects are supported by the absence of systemic toxicity. extract treatment results in a sustained and enhanced ability to reduce melanoma growth, followed by the restoration of innate and adopted antitumor immunity without affecting the overall physiology of the host.
PubMed: 38920557
DOI: 10.3390/diseases12060125 -
Frontiers in Immunology 2024[This corrects the article DOI: 10.3389/fimmu.2023.1152035.].
[This corrects the article DOI: 10.3389/fimmu.2023.1152035.].
PubMed: 38919618
DOI: 10.3389/fimmu.2024.1430460