A transcriptomic based deconvolution framework for assessing differentiation stages and drug responses of AML.

The diagnostic spectrum for AML patients is increasingly based on genetic abnormalities due to their prognostic and predictive value. However, information on the AML blast phenotype regarding their maturational arrest has started to regain importance due to its predictive power for drug responses. Here, we deconvolute 1350 bulk RNA-seq samples from five independent AML cohorts on a single-cell healthy BM reference and demonstrate that the morphological differentiation stages (FAB) could be faithfully reconstituted using estimated cell compositions (ECCs). Moreover, we show that the ECCs reliably predict ex-vivo drug resistances as demonstrated for Venetoclax, a BCL-2 inhibitor, resistance specifically in AML with CD14+ monocyte phenotype. We validate these predictions using LUMC proteomics data by showing that BCL-2 protein abundance is split into two distinct clusters for NPM1-mutated AML at the extremes of CD14+ monocyte percentages, which could be crucial for the Venetoclax dosing patients. Our results suggest that Venetoclax resistance predictions can also be extended to AML without recurrent genetic abnormalities and possibly to MDS-related and secondary AML. Lastly, we show that CD14+ monocytic dominated Ven/Aza treated patients have significantly lower overall survival. Collectively, we propose a framework for allowing a joint mutation and maturation stage modeling that could be used as a blueprint for testing sensitivity for new agents across the various subtypes of AML.

Evaluation of circulating tumor cells in colorectal cancer using flow cytometry.

OBJECTIVE: We aimed to evaluate the prognostic value of circulating tumor cells (CTCs) and the impact of intraoperative tumor manipulation on CTCs in colorectal cancer (CRC) patients. METHODS: We performed a prospective study on 40 patients with CRC stages I to IV who received curative surgery using the no-touch technique. Flow cytometry was used to identify CTCs in peripheral blood samples (4 mL/sample) collected at two surgical moments: skin incision (T1) and after surgical resection (T2). A threshold of ≥4 CTCs/4 mL blood was established for considering patients CTC positive. RESULTS: In the univariate analysis, CTC evaluation at T2 was correlated with female sex, vascular invasion, tumor localization in the colon and metastatic lymph nodes. In the multivariate analysis, only female sex and colon cancer maintained statistical significance. At a medium follow-up of 15 months (1-25 months), the mortality rate was 10% (n = 4), with no significant differences between the overall survival of T1 or T2 CTC-positive and CTC-negative patients. CONCLUSIONS: Flow cytometry is a feasible CTC identification technique in CRC, and although surgical manipulation has no influence on CTC numbers, CTCs may serve as a prognostic and predictive factor.

The MHC-II antigen presentation machinery and B7 checkpoint ligands display distinctive patterns correlated with acute myeloid leukaemias blast cells HLA-DR expression.

Acute Myeloid Leukaemia (AML) is a neoplasia characterised by rapid proliferation and an increased rate of relapses. The AML blasts display features of antigen-presenting cells (APC), and thus can directly modulate the anti-tumour T cell responses. The bone marrow of a group consisting of 30 newly diagnosed patients and four healthy donors (HD) was investigated for the expression of HLA-DR, several molecules involved in MHC-II antigen-presentation and MHC-II groove editing, like HLA-DM, CD74 and CLIP, as well as a set of immune checkpoint ligands, like ICOS-L, B7.2, PD-L2 and B7-H3. The patients were further characterised for their genetic anomalies and distributed to favourable, intermediate and adverse ELN risk categories. We were able to show that while 23% of our patients displayed a low level of HLA-DR surface expression, all patients displayed higher HLA-DM and CD74 expression compared to HD. However, a higher CLIP expression was noticed only in the HLA-DR low patients. The co-inhibitory PD-L2 and B7-H3 molecules were increased in the cases with normal HLA-DR expression; oppositely, the co-stimulatory ICOS-L and the dual function B7.2 were significantly increased in the cases with HLA-DR low expression. Furthermore, no favourable ELN risk cases were found within the HLA-DR low group. All in all, these data show that the AML with low versus normal HLA-DR expression display different profiles of MHC class II machinery molecules and B7 ligands, which are correlated with distinct ELN stratification. Furthermore, as our study included healthy individuals, it offers valuable information about the expression levels that should be considered as normal for these markers known to cause differences in peptide repertoires, reflected further in distinct T-cells polarisation pathways.

B7-Positive and B7-Negative Acute Myeloid Leukemias Display Distinct T Cell Maturation Profiles, Immune Checkpoint Receptor Expression, and European Leukemia Net Risk Profiles.

Acute myeloid leukemia (AML) is generally considered a poorly immunogenic malignancy, displaying a "non-inflamed" leukemia microenvironment (LME), leading to T cell tolerance. However, the immune landscape of AML is much more heterogeneous. Since B7 expression is regarded as a consequence of an interferon-mediated "inflammatory" phenotype, we have investigated by flow cytometry the B7 checkpoint ligands B7.1, B7.2, programmed death ligand 1 (PD-L1), PD-L2, ICOS-L, B7-H3, and B7-H4 on the AML blasts of 30 newly diagnosed patients and their corresponding receptors [cytotoxic T lymphocyte-associated protein 4 (CTLA-4), programmed death 1 (PD-1), and inducible T cell costimulator (ICOS)] on bone marrow (BM) T cell maturation populations. We could thus evidence B7-negative and B7-positive leukemias either with an isolated expression or part of eight different checkpoint ligand "signatures" that always included an inhibitory B7 molecule. B7-positive AMLs encompassed intermediate and adverse European Leukemia Net (ELN) risk cases and displayed mainly central memory CD4+ T cells with high ICOS levels and effector CD8+ T cells with high PD-1 expression. B7-negative cases were rather classified as AML with recurrent genetic anomalies and displayed predominantly naive T cells, with the exception of NPM1 mutated AMLs, which expressed B7-H3. These different B7 immune profiles suggest that specific immunotherapies are required to target the distinct immune evasion strategies of this genetically heterogeneous disease.

CONCENTRATIONS OF VITREAL CYTOKINES IN RHEGMATOGENOUS RETINAL DETACHMENT.

UNLABELLED: Proliferative vitreoretinopathy (PVR) is one of the most frequent causes of failure of rhegmatogenous retinal detachment (RRD) surgery. AIM: To measure the vitreous levels of granulocyte colony stimulating factor (G-CSF) and monocyte chemoattractant protein 1 (MCP-1) in eyes with RRD and in a control group. MATERIAL AND METHODS: A prospective study of 40 patients operated for RRD (study group) and 20 patients with epiretinal membrane or macular holes (selected as control group since they needed vitrectomy but had attached retinas). Vitreous samples were collected during vitrectomy and were assessed for the presence of cytokines using a fluorescent bead-based multiplex assay. RESULTS: The concentration of G-CSF (8.59 pg/ml) and MCP-1 (1615.2 pg/ml) were significantly increased in the study group, when compared to the control group (0 and 469.13 pg/ml, respectively). MCP-1 was also significantly increased in the subgroup of patients with PVR compared to the patients with uncomplicated RRD. CONCLUSIONS: The levels of these biomarkers support the idea that proliferative vitreoretinopathy has an inflammatory component.

Optimization of culture conditions for bone marrow stromal cells in RPMI-1640 medium.

UNLABELLED: Bone marrow mesenchymal stem cells are important for both research and clinical purpose. A number of culture methods for these cells are available on the market, many of them consisting of specialized growing media in combination with growth factors. Our goal was to optimize a less expensive culture method for bone marrow mesenchymal cells. MATERIAL AND METHODS: Eight samples of bone marrow aspirates from patients were used. Out these 8 samples 2 were from healthy people, 3 from chronic granulocytic leukemia patients, 2 from multiple myeloma patients and 2 from patients with myelodysplastic syndrome. Bone aspirates from healthy people were used to optimize the culture method and the rest were used for testing the optimized method. Two methods were tried: 1. Cell culture starting from whole bone marrow, 2) cell culture after bone marrow separation in density gradient with Histopaque. RESULTS: Cell culture starting from whole bone marrow gives better yields for mesenchymal stem cells than methods which include gradient density separation of mononuclear cells with Ficoll-Histopaque. CONCLUSIONS: We have optimised a less expensive cell culture method for bone marrow mesenchymal cells.

[Prognostic significance of leukemia-associated phenotype in correlation with other biologic markers in acute myeloid leukemia patients]. / Identificarea semnificatiei prognostice a fenotipului asociat leucemiei in corelatie cu alti markeri biologici la pacientii cu leucemie acuta mieloblastica.

UNLABELLED: Leukemic cells have unique aberrant phenotypes, which permit identification of this cells at diagnose and in evolution of the disease. Signaling molecules with other cells and bone marrow stroma are part of the leukemic cells phenotype. Genetic and molecular abnormalities have the main prognostic significance and confer the leukemic cell status. The main aim of the current study is to identify correlation between recognized prognostic factors in acute myeloid leukemia (AML) patients and other phenotypic markers. MATERIAL AND METHOD: Imunophenotypic analysis (BDFACS CantoII, FACSDiva Software) was performed on peripheral blood/bone marrow aspirate samples of 56 patients diagnosed with AML (9 M0, 3 M1, 10 M2, 4 M3, 28 M4/M5, 1 M6, 1 M7) between 2007-2009 in Hematology Department of "Sf. Spiridon" Hospital Iasi. We used an extended panel of monoclonal antibodies and we determined the level of expression of cytokines receptors (IL3Ra, IL7R) and chemokines (CXCR4, CKR5). RESULTS: In our study, IL7R expression on AML blasts was significant correlate with low WBC count at diagnosis (p = 0.04) and with multilinear displasia (p = 0.01), high CXCR4 expression was correlate (p = 0.05) with lack of response at first induction therapy and CD123 (IL3Ra) expression was correlate with M4 FAB phenotype. Survival was negative influenced by presence of IL3R on AML blasts, but flt3 mutations, CXCR4, IL7R expression on leukemic cells, other phenotypic aberrancies did not influenced treatment response and survival in our patients population. CONCLUSION: Complete investigation of leukemic cells phenotype extended with cytokines/chemokines receptors at diagnostic is useful for correct characterization of the disease, for discover new prognostic categories and for better identification of minimal residual disease.

Flow cytometry-based quantification of cytokine levels in AML patients plasma and cell culture supernatants.

AIM: Bone marrow stromal cells (BMSCs) have been found to support leukemic cell survival; however, the mechanisms responsible are far from being elucidated yet. The main aim of the current study is to identify particular cytokine/chemokine patterns of acute myeloid leukemia (AML) cells, and, on a longer term, to correlate them with the patient outcome and response to therapy. Therefore, the influence of BMSCs on in vitro modulation of cytokine secretion (IL-1beta, TNF-alpha, IL-10, IFN-gamma, IL-4, IL-5, and IL-2) by AML cells as well as the AML cells supportive capacity of BMSCs-derived soluble factors was investigated. MATERIAL AND METHODS: With this purpose, we used an in vitro experimental model consisting in the evaluation of the effect of BMSC confluent layers-conditioning medium (BMSC-CM) on M4/5 AML cell cultures. RESULTS: Our results show that BMSC-CM from both AML patients and healthy subjects conferred a substantial beneficial effect on AML cells throughout the culture (p=0.0002 and 0.0020 respectively at 24 hours and p=0,0013 and 0,0030 respectively at 72 hours), with a temporary increase in AML cell viability conferred by BM plasma from AML patients. Significant differences were observed with respect to IL1 b secretion which was upregulated in AML cell cultures both after 24 and 72 hours following the addition of AML-BMSC-CM, in contrast to control-BMSC-CM. CONCLUSION: Our results suggest the contribution of BMSCs from AML patients to the generation of particular factors which may be key players involved in the in vivo maintenance of the malignant clone.

Characterization of in vitro growth of multiple myeloma cells.

OBJECTIVE: To develop an in vitro culture system for rapid assessment of multiple myeloma (MM) cell growth. METHODS: MM cells lines (MMCLs) L363, U266, and RPMI-8226, and bone marrow (BM)-derived plasma cells (PCs) from MM patients were evaluated for their in vitro growth using various stroma (BMSC, M210-B4, and osteoclasts [OCs]) and cytokine support combinations (combination A: interleukin [IL]-6, vascular endothelial growth factor, insulin-like growth factor-1 vs combination B: A plus hepatocyte growth factor, IL-13 vs combination C: IL-6, insulin-like growth factor -1, stromal-derived growth factor-1, Galectin-1, IL-1alpha). RESULTS: We found a significant effect of stroma, notably affecting growth of L363 cells. Cytokine combination A had the highest growth impact, whereas B and C were of lesser benefit. The contribution of combined cytokines and stroma for MMCL growth was moderate and the viability of MMCLs was best preserved with OCs. One of the most commonly used PC-marker CD138, expressed on all MMCLs on day 0, showed a gradual downmodulation upon all culture conditions, possibly induced as a stroma-triggered phenotypic change, and leading to the ability of MM cells to dedifferentiate into immature, resilient phenotypes. PC-enriched BM samples from 7 of 10 MM patients could be maintained in culture, again profiting from stroma more than cytokines alone. CONCLUSIONS: Our data demonstrate a consistent growth advantage provided by BMSCs on MMCLs and primary MM cells, preserved viability with OCs, and phenotypic and morphologic heterogeneity of primary MM cells during culture. Further identification of key components involved in MM cell growth, coupled with our understanding of drug sensitivity offers the potential to better define the disease pathogenesis and to identify novel therapeutic targets.

[High values of soluble cytokeratin 18 in breast carcinomas may have different meanings]. / Valorile crescute ale citokeratinei 18 serice in neoplasmele mamare pot avea semnificatii diferite.

We have investigated the cellular and serum CK18 in 26 non-treated primary ductal invasive breast carcinomas. The soluble CK18 (TPS) was detected by chemiluminescent assay, and the cellular CK18 and PCNA expression by immunocytochemistry. Flow-cytometry was used to estimate the amount of DNA in malignant cells. There was a significant correlation between soluble CK18 and the pre-menopausal status (p < 0.05), characterized in our group by a PCNA estimated low proliferation index. We have also found a significant correlation between soluble CK18 and the DNA index (p < 0.01). The intracellular CK18 has correlated with the PCNA expression (p < 0.05), while no correlation could be found between cellular and serum CK18. The values of soluble CK18 may offer information about the treatment-induced cell death, if monitored, while isolated measurements should be interpreted cautiously. Elevated levels of serum CK18 in non-treated carcinomas may rather reflect a high tumor turn-over or perhaps a more intensive tumor cell killing.