Carsten Müller-Tidow

Chimeric antigen receptor transduced T cells - Tuning up for the next generation

Chimeric antigen receptor (CAR) T cell therapy has recently achieved impressive clinical outcome in patients with CD19‐positive hematologic malignancies. Extrapolation of CAR T cell treatment to solid tumors, however, has not yet yielded similar results. This might be due to intrinsic causes, e.g. insufficient CAR T cell activation or CAR toxicity as well as extrinsic factors displaying an unfavorable tumor environment for CAR T cells by raising physical and chemical barriers. In this review, we discuss the advantages as well as major obstacles of CAR T cell therapy, particularly in the context of solid tumors, and focus on efforts and novel strategies in CAR T cell development.

Prognostic factors of resected node-positive lung cancer: location, extent of nodal metastases, and multimodal treatment

Objective: To investigate the prognostic significance of location and extent of lymph node metastasis in resected non-small cell lung cancer (NSCLC), and to weigh up the influence of treatment modalities on survival. Patients and method: On exploratory analysis, patients were grouped according to location and time of diagnosis of nodal metastasis: group I, pN2-disease in the aortopulmonary region (N=14); group II, pN2-disease at other level (N=30); group III, cN2-disease with response to induction treatment (ypN0; N=21); group IV, cN2-disease without response to induction treatment (ypN1-2; N=27); group V, pN1-disease (N=66). Results: From 1999 to 2005, 158 patients (median age: 64 years) with node-positive NSCLC were treated at our institution either by neoadjuvant chemo-radiotherapy plus surgery or by surgery plus adjuvant therapy (chemotherapy, radiotherapy, or both). Operative mortality and major morbidity rates were 2% and 15%. Five-year survival rates were 19% for group I, 12% for group II, 66% for group III, 15% for group IV, and 29% for group V (P<.05). On multivariate analysis, time of N+-diagnosis, extent of nodal involvement and therapy approach were significantly linked to prognosis. Conclusion: The survival of patients with node-positive NSCLC does not depend on anatomical location of nodal disease, but strongly correlates to extent of nodal metastases and treatment modality. Combined therapy approaches including chemotherapy and surgery may improve long-term survival.

Differences in Expansion Potential of Naive Chimeric Antigen Receptor T Cells from Healthy Donors and Untreated Chronic Lymphocytic Leukemia Patients

Introduction Therapy with chimeric antigen receptor T (CART) cells for hematological malignancies has shown promising results. Effectiveness of CART cells may depend on the ratio of naive (TN) vs. effector (TE) T cells, TN cells being responsible for an enduring antitumor activity through maturation. Therefore, we investigated factors influencing the TN/TE ratio of CART cells. Materials and methods CART cells were generated upon transduction of peripheral blood mononuclear cells with a CD19.CAR-CD28-CD137zeta third generation retroviral vector under two different stimulating culture conditions: anti-CD3/anti-CD28 antibodies adding either interleukin (IL)-7/IL-15 or IL-2. CART cells were maintained in culture for 20 days. We evaluated 24 healthy donors (HDs) and 11 patients with chronic lymphocytic leukemia (CLL) for the composition of cell subsets and produced CART cells. Phenotype and functionality were tested using flow cytometry and chromium release assays. Results IL-7/IL-15 preferentially induced differentiation into TN, stem cell memory (TSCM: naive CD27+ CD95+), CD4+ and CXCR3+ CART cells, while IL-2 increased effector memory (TEM), CD56+ and CD4+ T regulatory (TReg) CART cells. The net amplification of different CART subpopulations derived from HDs and untreated CLL patients was compared. Particularly the expansion of CD4+ CARTN cells differed significantly between the two groups. For HDs, this subtype expanded >60-fold, whereas CD4+ CARTN cells of untreated CLL patients expanded less than 10-fold. Expression of exhaustion marker programmed cell death 1 on CARTN cells on day 10 of culture was significantly higher in patient samples compared to HD samples. As the percentage of malignant B cells was expectedly higher within patient samples, an excessive amount of B cells during culture could account for the reduced expansion potential of CARTN cells in untreated CLL patients. Final TN/TE ratio stayed <0.3 despite stimulation condition for patients, whereas this ratio was >2 in samples from HDs stimulated with IL-7/IL-15, thus demonstrating efficient CARTN expansion. Conclusion Untreated CLL patients might constitute a challenge for long-lasting CART effects in vivo since only a low number of TN among the CART product could be generated. Depletion of malignant B cells before starting CART production might be considered to increase the TN/TE ratio within the CART product.

Quantification of number of CD38 sites on bone marrow plasma cells in patients with light chain amyloidosis and smoldering multiple myeloma: NUMBER OF CD38 SITES ON BONE MARROW PLASMA CELLS

Recent approaches in multiple myeloma (MM) treatment have targeted CD38. As antigen expression levels on plasma cells (PCs) were demonstrated to affect response to monoclonal antibody (mAb) treatment, a precise characterization of PC phenotype is warranted.

DNMTi/HDACi combined epigenetic targeted treatment induces reprogramming of myeloma cells in the direction of normal plasma cells

BackgroundMultiple myeloma (MM) is the second most common hematologic malignancy. Aberrant epigenetic modifications have been reported in MM and could be promising therapeutic targets. As response rates are overall limited but deep responses occur, it is important to identify those patients who could indeed benefit from epigenetic-targeted therapy.MethodsSince HDACi and DNMTi combination have potential therapeutic value in MM, we aimed to build a GEP-based score that could be useful to design future epigenetic-targeted combination trials. In addition, we investigated the changes in GEP upon HDACi/DNMTi treatment.ResultsWe report a new gene expression-based score to predict MM cell sensitivity to the combination of DNMTi/HDACi. A high Combo score in MM patients identified a group with a worse overall survival but a higher sensitivity of their MM cells to DNMTi/HDACi therapy compared to a low Combo score. In addition, treatment with DNMTi/HDACi downregulated IRF4 and MYC expression and appeared to induce a mature BMPC plasma cell gene expression profile in myeloma cell lines.ConclusionIn conclusion, we developed a score for the prediction of primary MM cell sensitivity to DNMTi/HDACi and found that this combination could be beneficial in high-risk patients by targeting proliferation and inducing maturation.

Successful collection of peripheral blood stem cells upon VIDE chemomobilization in sarcoma patients

In patients with Ewing sarcoma and some distinct subgroups of soft tissue sarcoma (STS), a quantitatively sufficient autologous peripheral blood stem cell (PBSC) collection for stem cell support might facilitate treatment continuation, dose‐intensification, and high‐dose chemotherapy. Here, we provide a detailed evaluation of PBSC collection upon vincristine, ifosfamide, doxorubicin, and etoposide (VIDE) chemomobilization.

Metastatic Triple Negative Breast Cancer patient with TP53 tumor mutation experienced 11 months progression-free survival on bortezomib monotherapy without adverse events after ending standard treatments with grade 3 adverse events

A triple-negative breast cancer patient had no hereditary BRCA1, BRCA2, or TP53 risk variants. After exhaustion of standard treatments, she underwent experimental treatments and whole-exome sequencing of tumor, blood, and a metastasis. Well-tolerated experimental bortezomib monotherapy was administered for a progression-free period of 11 mo. After progression, treatments were changed and the exome data were evaluated, expanded with RNA and exome sequencing of a late-stage metastasis. In the final stage, eribulin alone and in combination with anthracyclines were administered. While suffering from grade 3 adverse events, skin metastases progressed. She lived 51 mo after initial diagnosis. Toxicity from anthracyclines and cisplatin may have been due to associated germline variants CBR3 C4Y and V224M and GSTP1 I105V, respectively. Somatic mutations predicted or reported as pathogenic were detected in 38 genes in tumor tissues. All tumor samples harbored the heterozygous TP53 Y220C variant, known to destabilize p53 and down-regulate p53-mediated apoptosis. The success of bortezomib may be explained by the previously reported up-regulation of caspase-mediated apoptosis, which is p53-independent. Phylogenetic analysis of blood, primary tumor, and two metastases inferred an ancestral tumor cell with 12 expressed tumor mutations from which all three tumors may have evolved. Although our first urgent analysis could only include 40 genes, postmortem analysis uncovered the aggressiveness and suggested experimental therapies including 16 actionable targets, partly validated by immunohistochemistry. Exome and transcriptome analyses yielded comprehensive therapy-relevant information and should be considered for patients at first diagnosis.

The prognostic and predictive value of IKZF1 and IKZF3 expression in T-cells in patients with multiple myeloma

ABSTRACT Purpose: While recent studies described the role of IKZF1/3 proteins in multiple myeloma (MM) cells, few have highlighted the significance of IKZF1/3 expression in T-cells. In this study we examine the prognostic and predictive value of IKZF1/3 expression in T-cells in patients with MM stage III. Experimental design: We analysed the IKZF1/3 expression levels in T-cells from 45 MM stage I (MMI) and 50 newly diagnosed MM stage III (MMIII) patients, according to Durie-Salmon staging system, by flow cytometry to examine their prognostic and predictive value. We also combined in vivo observations with in vitro assays to determine the effect of IKZF1/3 expression on the T-cell immunophenotype and anti-tumour T-cell response in 162 MMIII patients. Results: We found that high IKZF3, but not IKZF1, expression in T-cells correlates with superior overall survival in MMIII patients treated with immunomodulatory drugs (thalidomide, lenalidomide and pomalidomide). Moreover, we show that higher IKZF3 expression in T-cells inhibits myeloma-specific T-cell response in vitro and that the immunophenotype of patients with high IKZF3 expression shows features that are contrary to the changes induced by immunomodulatory drugs. Although we observed higher IKZF3 expression levels in T-cells from patients with MMIII compared to MMI, IKZF3 expression was unaffected by the tumour microenvironment. Conclusion: In conclusion, IKZF3 expression in T-cells is a predictive value for clinical outcome in MMIII patients treated with immunomodulatory drugs due to its profound modulation of T-cell functionality.

Improving consolidation therapy in acute myeloid leukemia - a tough nut to crack

After intensive induction therapy, 60% to 80% of younger (≤60 years) and 40% to 60% of older (>60 years) patients with acute myeloid leukemia (AML) achieve a complete remission.[1][1] However, despite intensive consolidation therapy including intensive chemotherapy, autologous or allogeneic

Reptin drives tumour progression and resistance to chemotherapy in nonsmall cell lung cancer

While targeted nonsmall cell lung cancer (NSCLC) therapies have improved the outcome of defined disease subtypes, prognosis for most patients remains poor. We found the AAA+ ATPase Reptin to be highly expressed in the vast majority of 278 NSCLC tumour samples. Thus, the objective of the study was to assess the role of Reptin in NSCLC. Survival analyses of 1145 NSCLC patients revealed that high RNA expression levels of Reptin are associated with adverse outcome. Knockdown of Reptin in human NSCLC cells impaired growth ex vivo and eliminated engraftment in a xenograft model. Reptin directly interacted with histone deacetylase 1 (HDAC1) as the critical mechanism driving NSCLC tumour progression. Pharmacological disruption of the Reptin/HDAC1 complex resulted in a substantial decrease in NSCLC cell proliferation and induced significant sensitisation to cisplatin. Our results identify Reptin as a novel independent prognostic factor and as a key regulator mediating proliferation and clonal growth of human NSCLC cells ex vivo and in vivo. We unveil a Reptin/HDAC1 protein complex whose pharmacological disruption sensitises NSCLC cells to cisplatin, suggesting this approach for application in clinical trials. The AAA+ ATPase Reptin confers tumour progression, resistance to chemotherapy and poor outcome in NSCLC patients http://ow.ly/dLxW30kaUVu