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Salmenniemi, U.

Publications and source records attributed to Salmenniemi, U..

3 recordsLinked to original sources

Automated and closed clinical-grade manufacturing protocol produces potent NK cells against neuroblastoma cells and AML blasts

Natural killer (NK) cells have great potential as allogeneic immune cell therapy due to their natural ability to recognize and kill tumor cells, and due to their apparent safety. This study describes the development of an immunotherapy option tailored for high-risk acute myeloid leukemia (AML) in adults and neuroblastoma in children. A GMP-compliant manufacturing protocol for the local production of functionally potent NK cells is detailed in the study, including a comprehensive description of the quality control strategy and considerations for product batch specifications in early clinical development. The protocol is based on the closed, automated CliniMACS Prodigy(R) platform (Miltenyi Biotec) and a modified Natural Killer Cell Transduction (NKCT) process without transduction and expansion. NK cells are isolated from leukapheresis through CD3 depletion and CD56 enrichment, followed by a 12-hour activation with cytokines (500 IU/ml IL-2, 140 IU/ml IL-15). Three CliniMACS Prodigy(R) NKCT processes were executed, demonstrating the feasibility and consistency of the modified NKCT process. A three-step process without expansion, however, compromised the NK cell yield. T cells were depleted effectively, indicating excellent safety of the product for allogeneic use. Phenotypic and functional characterization of the NK cells before and after cytokine activation revealed a notable increase in the expression of activation markers, particularly CD69, consistent with enhanced functionality. Intriguingly, even following a brief 12-hour activation period, the NK cells exhibited increased killing efficacy against CD33+ AML blasts isolated from patients and against SH-SY5Y neuroblastoma (NBL) target cells in vitro, suggesting a potential therapeutic benefit for AML and NBL patients.

immunology↗

Discovery of NOvel CIP2A VAriant (NOCIVA) and its clinical relevance in myeloid leukemias

Cancerous inhibitor of PP2A (CIP2A) is a prevalent human oncoprotein that inhibits tumor suppressor PP2A-B56a. However, CIP2A mRNA and protein variants remain uncharacterized. Here, we report discovery of a CIP2A splicing variant NOCIVA (NOvel CIp2a VAriant). NOCIVA contains CIP2A exons 1-13 fused to a continuous stretch of 349 nucleotide from CIP2A intron 13. Intriguingly, the first 39 nucleotides of the NOCIVA specific sequence are in coding frame with exon 13 of CIP2A, and codes for a 13 amino acid peptide tail unhomologous to any known human protein sequence. Therefore, NOCIVA translates to a unique human protein. NOCIVA retains the capacity to bind to B56a, but whereas CIP2A is predominantly a cytoplasmic protein, NOCIVA translocates to nucleus. Indicative of prevalent alternative splicing from CIP2A to NOCIVA in myeloid malignancies, acute myeloid leukemia (AML) and chronic myeloid leukemia (CML) patient samples overexpress NOCIVA, but not CIP2A mRNA. In AML, high NOCIVA mRNA expression is a marker for adverse overall survival. In CML, high NOCIVA expression associates with inferior event free survival among imatinib treated patients, but not among patients treated with dasatinib or nilotinib. Collectively, we describe discovery of a novel variant of oncoprotein CIP2A, and its clinical relevance in myeloid leukemias. Key PointsO_LIDiscovery and characterization of a first mRNA variant of one of the most prevalently deregulated human oncoproteins CIP2A C_LIO_LIUnlike CIP2A, NOCIVA mRNA is overexpressed in AML and CML patient samples and associates with poor clinical response in both myeloid cancers C_LI

cancer biology↗

ARPP19 promotes MYC expression and associates with patient relapse in acute myeloid leukemia

Despite of extensive genetic analysis of acute myeloid leukemia (AML), we still do not understand comprehensively mechanism that promote disease relapse from standard chemotherapy. Based on recent indications for non-genomic inhibition of tumor suppressor protein phosphatase 2A (PP2A) in AML, we examined mRNA expression of PP2A inhibitor proteins in AML patient samples. Notably, out of examined PP2A inhibitor proteins, overexpression of ARPP19 mRNA was found independent of current AML risk classification. Functionally, ARPP19 promoted AML cell viability and expression of oncoproteins MYC, CDK1, and another PP2A inhibitor CIP2A. Clinically, ARPP19 mRNA expression was significantly lower at diagnosis (p=0.035) in patients whose disease did not relapse after standard chemotherapy. ARPP19 was an independent predictor for relapse both in univariable (p=0.007) and in multivariable analyses (p=0.0001); and gave additive information to EVI1 expression and risk group status (additive effect, p=0.005). Low ARPP19 expression also associated with better patient outcome in TCGA LAML cohort (p=0.019). In addition, in matched patient samples from diagnosis, remission and relapse phases, ARPP19 expression associated with disease activity (p=0.034).\n\nTogether, these data identify ARPP19 as a novel oncogenic PP2A inhibitor protein in AML, and demonstrate its risk group independent role in predicting AML patient relapse tendency.

cancer biology↗