Physical exercise recommendations for patients with chronic myeloid leukemia based on individual preferences identified in a large international patient survey study of the East German Study Group for Hematology and Oncology (OSHO #97)

Background

Tyrosine kinase inhibitors (TKIs) have significantly lowered mortality of chronic myeloid leukemia (CML) patients adjusting life expectancy to that of the standard population. However, CML and its treatment with TKIs causes a high disease burden. Physical exercise (PE) could be a non-pharmacological approach to reducing these and improving quality of life.

Purpose

The aim of this study was to determine the individual disease burden as well as PE preferences of CML patients and to deduce thereof specific PE recommendations.

Methods

This multicenter survey was conducted in cooperation with the LeukaNET/Leukemia-patient network including CML patients aged ≥18 years (German Registry of Clinical Trials, DRKS00023698). The severity of selected symptoms was assessed using the adapted Myeloproliferative Neoplasms Symptom Assessment Form: 0 (absent), 1-30 (mild), 31-70 (moderate), or 71-100 (severe). Information about patients' PE needs and preferences depending on their motivation was recorded.

Results

A total of 212 questionnaires were analyzed (52% female, median age 54 years). The prevalence of moderate-to-severe symptoms was 49% for fatigue, 40% for musculoskeletal pain, and 37% for concentration problems. Other commonly reported symptoms included skin reactions (42%) and weight gain (24%). The proportion of overweight/obese patients was 52%. Half of all respondents requested more information regarding PE. Patients with CML preferred individual training (82%), located outdoors (71%), at home (47%), or in an indoor swimming pool (31%). Regarding the training frequency, sports-inactive patients preferred a frequency of 1-2 training sessions per week, whereas sports-active patients preferred 3-4 sessions per week (p <0.001). Sports-inactive patients preferred a training time of 15-45 minutes, while sports-active patients preferred 30-60 minutes (p = 0.002). Subsequently, PE recommendations were developed for patients with CML. Combined resistance and endurance training (moderate intensity twice per week for 30 minutes) was recommended for beginners. Obese patients should prioritize joint-relieving sports. To reduce the risk of skin reactions, direct sunlight and possibly water sports should be avoided, and UV protection should be used.

Conclusion

Counseling and motivation of CML patients to be physically active should be part of the standard of care as well as support for implementation.

Cross-Species Comparison of the Pan-RAF Inhibitor LY3009120's Anti-Tumor Effects in Equine, Canine, and Human Malignant Melanoma Cell Lines

Malignant melanomas (MMs) are the abnormal proliferation of melanocytes and are one of the lethal skin cancers in humans, equines, and canines. Accordingly, MMs in companion animals can serve as naturally occurring animal models, completing conventional cancer models. The common constitutive activation of the MAPK and PI3K pathways in MMs has been described in all three species. Targeting the related pathways is considered a potential option in comparative oncologic approaches. Herein, we present a cross-species comparative analysis exposing a set of ten melanoma cell lines (one human, three equine, and six canine) derived from primary tumors or metastasis to a pan-RAF and RAF dimer inhibitor (LY3009120). Cellular response (proliferation, biomass, metabolism, early and late apoptosis/necrosis, and morphology) and the presence of pathogenic single-nucleotide variants (SNVs) within the mutational hotspot genes BRAF exon 11 and 15, NRAS exon 2 and 3, KRAS exon 2, and KIT exon 11 were analyzed. This study showed that equine malignant melanoma (EMM) cells (MelDuWi) harbor the KRAS p.Q61H mutation, while canine malignant melanoma (CMM) cells (cRGO1 and cRGO1.2) carry NRAS p.G13R. Except for EMM metastasis cells eRGO6 (wild type of the above-mentioned hotspot genes), all melanoma cell lines exhibited a decrease in dose dependence after 48 and 72 h of exposure to LY3009120, independent of the mutation hotspot landscape. Furthermore, LY3009120 caused significant early apoptosis and late apoptosis/necrosis in all melanoma cell lines except for eRGO6. The anti-tumor effects of LY3009120 were observed in nine melanoma cell lines, indicating the potential feasibility of experimental trials with LY3009120. The present study reveals that the irradiation-resistant canine metastasis cells (cRGO1.2) harboring the NRAS p.G13R mutation are significantly LY3009120-sensitive, while the equine metastases-derived eRGO6 cells show significant resistance to LY3009120, which make them both valuable tools for studying resistance mechanisms in comparative oncology.

Abdominal venous thromboses: detection of the JAK2 p.V617F mutation by next-generation ultradeep sequencing-A prevalence study of patients in Mecklenburg-West Pomerania (2017-2021)

Background

Abdominal venous thromboses are rare thrombotic events with heterogeneous etiologies. They are related to myeloproliferative neoplasms (MPNs) in some patients and can occur as first signs of the disease. MPNs are characterized by mutations in the genes of Janus kinase 2 (JAK2), myeloproliferative leukemia virus oncogene (MPL), and calreticulin (CALR).

Methods

Within the prospective trial "Prevalence of JAK2 mutations in patients with abdominal venous thromboses" (JAK2 MV study; German Clinical Trials Register: DRKS00026943), the peripheral blood of patients with abdominal venous thromboses in Mecklenburg-West Pomerania, a federal state located in north-east Germany, was analyzed by next-generation ultradeep sequencing for MPN-associated mutations. Clinical characteristics and blood cell counts were also of interest. The primary endpoint was the detection of the mutation JAK2 p.V617F. Secondary endpoints were the detection of other acquired variants of JAK2, as well as MPL and CALR.

Results

A total of 68 patients with abdominal venous thromboses were included from February 2017 to January 2021, with splanchnic veins affected in 65 patients. The mutation JAK2 p.V617F was present in 13 patients (19%), with four patients showing low variant allele frequencies (VAF 0.1% to 1.9%). The time interval from the thrombotic event to analysis was longer for patients with the mutation. The mutation MPL p.W515R was detected in three cases, all of them with low VAF. One patient among them had a concurrent mutation of JAK2 p.V617F. The mutations CALR type I or type II were not found.

Discussion

By analyzing peripheral blood for the mutation JAK2 p.V617F, an important cause of these rare thrombotic events can be identified. The development of a diagnostic workup with next-generation ultradeep sequencing for the analysis of the JAK2 p.V617F mutation and further mutations has the potential to better understand the etiology of abdominal venous thromboses in individual patients in regional clinical care, as abdominal venous thromboses are diagnosed by various medical disciplines.

Exploring Thiazolopyridine AV25R: Unraveling of Biological Activities, Selective Anti-Cancer Properties and In Silico Target and Binding Prediction in Hematological Neoplasms

Thiazolopyridines are a highly relevant class of small molecules, which have previously shown a wide range of biological activities. Besides their anti-tubercular, anti-microbial and anti-viral activities, they also show anti-cancerogenic properties, and play a role as inhibitors of cancer-related proteins. Herein, the biological effects of the thiazolopyridine AV25R, a novel small molecule with unknown biological effects, were characterized. Screening of a set of lymphoma (SUP-T1, SU-DHL-4) and B- acute leukemia cell lines (RS4;11, SEM) revealed highly selective effects of AV25R. The selective anti-proliferative and metabolism-modulating effects were observed in vitro for the B-ALL cell line RS4;11. Further, we were able to detect severe morphological changes and the induction of apoptosis. Gene expression analysis identified a large number of differentially expressed genes after AV25R exposure and significant differentially regulated cancer-related signaling pathways, such as VEGFA-VEGFR2 signaling and the EGF/EGFR pathway. Structure-based pharmacophore screening approaches using in silico modeling identified potential biological AV25R targets. Our results indicate that AV25R binds with several proteins known to regulate cell proliferation and tumor progression, such as FECH, MAP11, EGFR, TGFBR1 and MDM2. The molecular docking analyses indicates that AV25R has a higher binding affinity compared to many of the experimentally validated small molecule inhibitors of these targets. Thus, here we present in vitro and in silico analyses which characterize, for the first time, the molecular acting mechanism of AV25R, including cellular and molecular biologic effects. Additionally, this predicted the target binding of the molecule, revealing a high affinity to cancer-related proteins and, thus, classified AVR25 for targeted intervention approaches.

The TiHoCL panel for canine lymphoma: a feasibility study integrating functional genomics and network biology approaches for comparative oncology targeted NGS panel design

Targeted next-generation sequencing (NGS) enables the identification of genomic variants in cancer patients with high sensitivity at relatively low costs, and has thus opened the era to personalized human oncology. Veterinary medicine tends to adopt new technologies at a slower pace compared to human medicine due to lower funding, nonetheless it embraces technological advancements over time. Hence, it is reasonable to assume that targeted NGS will be incorporated into routine veterinary practice in the foreseeable future. Many animal diseases have well-researched human counterparts and hence, insights gained from the latter might, in principle, be harnessed to elucidate the former. Here, we present the TiHoCL targeted NGS panel as a proof of concept, exemplifying how functional genomics and network approaches can be effectively used to leverage the wealth of information available for human diseases in the development of targeted sequencing panels for veterinary medicine. Specifically, the TiHoCL targeted NGS panel is a molecular tool for characterizing and stratifying canine lymphoma (CL) patients designed based on human non-Hodgkin lymphoma (NHL) research outputs. While various single nucleotide polymorphisms (SNPs) have been associated with high risk of developing NHL, poor prognosis and resistance to treatment in NHL patients, little is known about the genetics of CL. Thus, the ~100 SNPs featured in the TiHoCL targeted NGS panel were selected using functional genomics and network approaches following a literature and database search that shielded ~500 SNPs associated with, in nearly all cases, human hematologic malignancies. The TiHoCL targeted NGS panel underwent technical validation and preliminary functional assessment by sequencing DNA samples isolated from blood of 29 lymphoma dogs using an Ion Torrent™ PGM System achieving good sequencing run metrics. Our design framework holds new possibilities for the design of similar molecular tools applied to other diseases for which limited knowledge is available and will improve drug target discovery and patient care.

Addendum to the German Consensus Recommendations on Ponatinib in the Treatment of Chronic Myeloid Leukemia

BACKGROUND

Based on the new data from the primary analysis of the OPTIC (Optimizing Ponatinib Treatment in CP-CML) trial on dose optimization of ponatinib in patients with chronic phase (CP)-CML, the German consensus paper on ponatinib published in 2020 (Saussele S et al., Acta Haematol. 2020) has been updated in this addendum.

SUMMARY

Focus is on the update of efficacy and safety of ponatinib, reflecting the new data set, as well as the update of the benefit-risk assessment and recommendations for ponatinib starting dose in CP-CML - provided that the decision to use ponatinib has already been made. Furthermore, based on OPTIC and additional empirical data, the expert panel collaborated to develop a decision tree for ponatinib dosing, specifically for intolerant and resistant patients. The recommendations on cardiovascular management have also been updated based on the most recent 2021 guidelines of the European Society of Cardiology (ESC) on cardiovascular disease prevention in clinical practice.

KEY MESSAGES

The OPTIC data confirm the high efficacy of ponatinib in patients with CP-CML and provide the basis for individualized dose adjustment during the course of treatment.

Origin of breath isoprene in humans is revealed via multi-omic investigations

Plants, animals and humans metabolically produce volatile isoprene (C5H8). Humans continuously exhale isoprene and exhaled concentrations differ under various physio-metabolic and pathophysiological conditions. Yet unknown metabolic origin hinders isoprene to reach clinical practice as a biomarker. Screening 2000 individuals from consecutive mass-spectrometric studies, we herein identify five healthy German adults without exhaled isoprene. Whole exome sequencing in these adults reveals only one shared homozygous (European prevalence: <1%) IDI2 stop-gain mutation, which causes losses of enzyme active site and Mg2+-cofactor binding sites. Consequently, the conversion of isopentenyl diphosphate to dimethylallyl diphosphate (DMAPP) as part of the cholesterol metabolism is prevented in these adults. Targeted sequencing depicts that the IDI2 rs1044261 variant (p.Trp144Stop) is heterozygous in isoprene deficient blood-relatives and absent in unrelated isoprene normal adults. Wild-type IDI1 and cholesterol metabolism related serological parameters are normal in all adults. IDI2 determines isoprene production as only DMAPP sources isoprene and unlike plants, humans lack isoprene synthase and its enzyme homologue. Human IDI2 is expressed only in skeletal-myocellular peroxisomes and instant spikes in isoprene exhalation during muscle activity underpins its origin from muscular lipolytic cholesterol metabolism. Our findings translate isoprene as a clinically interpretable breath biomarker towards potential applications in human medicine.

Physical exercise recommendations for patients with polycythemia vera based on preferences identified in a large international patient survey study of the East German Study Group for Hematology and Oncology (OSHO #97)

BACKGROUND

Exercise therapy during cancer treatment reduces symptom burden and improves quality of life (QoL). Polycythemia vera (PV) is a myeloproliferative neoplasia associated with good overall survival (up to decades) but a significant symptom burden, including thromboembolic events and dysesthesias. There are no specific exercise recommendations for patients with PV. Thus, we aimed to determine the exercise preferences of patients with PV and to derive specific recommendations based on the most commonly reported symptoms.

METHODS

This multicenter survey included patients with PV ≥18 years old. Demographic, clinical, and disease burden data were collected. The severity of selected symptoms was assessed using the adapted Myeloproliferative Neoplasms Symptom Assessment Form: 0 (absent), 1-30 (mild), 31-70 (moderate), or 71-100 (severe). The patients' information needs about physical activity (PA) and exercise preferences were recorded depending on their motivation and analyzed with regard to demographic aspects.

RESULTS

The sample comprised 182 patients (68% female, 61 ± 12 years). The prevalence of moderate-to-severe symptoms was 60% for fatigue, 44% for concentration problems, and 35% for bone/muscle pain. Other commonly reported symptoms included skin reactions (49%), splenomegaly (35%), and increased bleeding tendency (28%). Overall, 67% of respondents requested more information regarding PA. Patients with PV preferred individual training (79%) located outdoors (79%) or at home (56%). Regarding the amount of training, sports-inactive patients preferred a frequency of 1-2 times/week and session durations of 15-45 min, whereas sports-active patients preferred 3-4 times/week and 30-60 min (p < 0.001). Higher sport-inactiveness was observed in patients with lower educational level compared to patients with higher educational level (69% vs. 50%, p = 0.021). For beginners, combined resistance-endurance (circuit) training two times/week, which can be performed outdoors or at home, should be recommended. In the case of splenomegaly or bleeding symptoms, exercises with a low injury risk should be chosen.

CONCLUSION

PA is important for patients with PV; therefore, counseling should be integrated into the treatment plan. Specifically, patients with low educational level should be addressed. Prospective studies are warranted to evaluate the effects of the novel exercise recommendations.

Short-term immune-checkpoint inhibition partially rescues perturbed bone marrow hematopoiesis in mismatch-repair deficient tumors

Wide-spread cancer-related immunosuppression often curtails immune-mediated antitumoral responses. Immune-checkpoint inhibitors (ICIs) have become a state-of-the-art treatment modality for mismatch repair-deficient (dMMR) tumors. Still, the impact of ICI-treatment on bone marrow perturbations is largely unknown. Using anti-PD1 and anti-LAG-3 ICI treatments, we here investigated the effect of bone marrow hematopoiesis in tumor-bearing Msh2loxP/loxP;TgTg(Vil1-cre) mice. The OS under anti-PD1 antibody treatment was 7.0 weeks (vs. 3.3 weeks and 5.0 weeks, control and isotype, respectively). In the anti-LAG-3 antibody group, OS was 13.3 weeks and thus even longer than in the anti-PD1 group (p = 0.13). Both ICIs induced a stable disease and reduced circulating and splenic regulatory T cells. In the bone marrow, a perturbed hematopoiesis was identified in tumor-bearing control mice, which was partially rescued by ICI treatment. In particular, B cell precursors and innate lymphoid progenitors were significantly increased upon anti-LAG-3 therapy to levels seen in tumor-free control mice. Additional normalizing effects of ICI treatment were observed for lin-c-Kit+IRF8+ hematopoietic stem cells, which function as a "master" negative regulator of the formation of polymorphonuclear-myeloid-derived suppressor cell generation. Accompanying immunofluorescence on the TME revealed significantly reduced numbers of CD206+F4/80+ and CD163+ tumor-associated M2 macrophages and CD11b+Gr1+ myeloid-derived suppressor cells especially upon anti-LAG-3 treatment. This study confirms the perturbed hematopoiesis in solid cancer. Anti-LAG-3 treatment partially restores normal hematopoiesis. The interference of anti-LAG-3 with suppressor cell populations in otherwise inaccessible niches renders this ICI very promising for subsequent clinical application.

Uncoupling protein 2 deficiency of non-cancerous tissues inhibits the progression of pancreatic cancer in mice

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is a disease of the elderly mostly because its development from preneoplastic lesions depends on the accumulation of gene mutations and epigenetic alterations over time. How aging of non-cancerous tissues of the host affects tumor progression, however, remains largely unknown.

METHODS

We took advantage of a model of accelerated aging, uncoupling protein 2-deficient (Ucp2 knockout, Ucp2 KO) mice, to investigate the growth of orthotopically transplanted Ucp2 wild-type (WT) PDAC cells (cell lines Panc02 and 6606PDA) in vivo and to study strain-dependent differences of the PDAC microenvironment.

RESULTS

Measurements of tumor weights and quantification of proliferating cells indicated a significant growth advantage of Panc02 and 6606PDA cells in WT mice compared to Ucp2 KO mice. In tumors in the knockout strain, higher levels of interferon-γ mRNA despite similar numbers of tumor-infiltrating T cells were observed. 6606PDA cells triggered a stronger stromal reaction in Ucp2 KO mice than in WT animals. Accordingly, pancreatic stellate cells from Ucp2 KO mice proliferated at a higher rate than cells of the WT strain when they were incubated with conditioned media from PDAC cells.

CONCLUSIONS

Ucp2 modulates PDAC microenvironment in a way that favors tumor progression and implicates an altered stromal response as one of the underlying mechanisms.

Vector-based SARS-CoV-2 vaccination is associated with improved T-cell responses in hematological neoplasia

In order to elucidate mechanisms for SARS-CoV-2 vaccination success in hematological neoplasia, we herein provide a comprehensive characterization of the spike-specific T-cell and serological immunity induced in 130 patients in comparison to 91 healthy controls. We studied 121 distinct T-cell subpopulations and the vaccination schemes as putative response predictors. In patients with lymphoid malignancies an insufficient IgG response was accompanied by a normal CD4+ T-cell function. Compared to controls, a spike-specific CD4+ response was detectable in fewer patients with myeloid neoplasia whereas the seroconversion rate was normal. In-depth immunophenotyping demonstrated in particular, that CD4+ T-cells and naïve CD4+ T-cells were reduced in both patient cohorts without differences between the groups. Vaccination-induced CD4+ responses were associated to CD8+ and IgG responses. Vector-based AZD1222 vaccine induced more frequently detectable specific CD4+ responses in study participants across all cohorts (27/28, 96%), whereas fully mRNA based vaccination schemes resulted in measurable CD4+ cells in 102/168 participants only (61%, p<0.0001). A similar benefit of vector-based vaccination was observed for the induction of spike-specific CD8+ T-cells. Multivariable models confirmed vaccination schemes that incorporated at least one vector-based vaccination as key feature to mount both a spike-specific CD4+ (odds ratio 10.67) and CD8+ response (odds ratio 6.56). Multivariable analyses identified a specific CD4+ response, but not the vector-based immunization as beneficial for a strong specific IgG titer. Our study reveals factors associated with a T-cell response in patients with hematologic neoplasia and might pave the way towards tailored vaccination schemes for vaccinees suffering from these diseases. The study is registered at the German Clinical Trials Register (DRKS00027372).

Different treatment strategies versus a common standard arm (CSA) in patients with newly diagnosed AML over the age of 60 years: a randomized German inter-group study

A randomized inter-group trial comparing more intensive treatment strategies to a common standard arm 3 + 7 (CSA) was conducted in patients with non-M3 AML. Untreated patients ≥ 60 years were allocated to the CSA (n = 132) or to the study group arms (n = 1154) of the AMLCG (TAD/HAM versus HAM/HAM ± G-CSF followed by TAD and maintenance) and the OSHO (intermediate-dose ara-C/mitoxantrone followed by ara-C/mitoxantrone). Median age of the 1147 eligible patients was 69 (range 60-87) years. CR/CRi status at 90 days was not significantly different between the CSA (54% (95%CI: 45-64)) and the study group arms (53% (95%CI: 47-60) and 59% (95%CI: 58-63)). The five-year event-free survival (EFS) probability (primary endpoint) was 6.2% (95%CI: 2.7-14.0) in the CSA, 7.6% (95%CI: 4.5-12.8) in study group A and 11.1% (95%CI: 9.0-13.7) in B. The 5-year OS was 17.2% (95%CI: 11.0-26.9), 17.0% (95%CI: 2.0-23.9), and 19.5% (95%CI: 16.7-22.8) in CSA, study group A and B, respectively. Neither study group differed significantly from the CSA regarding EFS, OS, or relapse-free survival. In multivariate analyses, allocation to the treatment strategy was not significantly associated with the time-to-event endpoints. The evaluation of more intensive treatment strategies did not show clinically relevant outcome differences when compared to CSA.

Anxieties, age and motivation influence physical activity in patients with myeloproliferative neoplasms - a multicenter survey from the East German study group for hematology and oncology (OSHO #97)

Background

Physical activity (PA) is a non-pharmacological approach to alleviate symptom burden and improve health-related quality of life (HrQoL) in cancer patients (pts). Whether pts with myeloproliferative neoplasms (MPN) PA behavior changes due to symptom burden and/or knowledge of the putative beneficial effects of PA has not yet been investigated.

Methods

We performed a large questionnaire study in MPN pts. Self-reported PA behavior and potential influencing factors of 634 MPN pts were analyzed. Questionnaires were used to assess demographics, anxiety, severity of symptoms, HrQoL, current level of everyday and sports activities, and the level of information regarding the importance/possibilities of PA. According to their PA, the pts were assigned to the three groups: "inactive", "non-targeted active", and "sporty active" and compared with each other.

Results

Key findings are that in 73% of the pts, the disease had an impact on PA, with 30% of pts reducing their PA. The prevalence of anxieties (e.g., occurrence of thrombosis and bleeding) regarding PA was 45%. Sporty active pts had a lower symptom burden and better HrQoL (p ≤ 0.001) compared to the other groups. Inactive pts were significantly older and had a higher body mass index than sporty active pts. Inactive and non-targeted active pts felt less informed about the importance/possibilities of PA (p = 0.002).

Conclusion

Our results suggest that especially older and non-sporty MPN pts could benefit from motivational as well as disease-specific PA information. This study was registered at the German Registry of Clinical Trials, DRKS00023698.

CDK4/6 blockade provides an alternative approach for treatment of mismatch-repair deficient tumors

Mismatch repair-deficient (dMMR) tumors show a good response toward immune checkpoint inhibitors (ICI), but developing resistance impairs patients’ outcomes. Here, we compared the therapeutic potential of an α-PD-L1 antibody with the CDK4/6 inhibitor abemaciclib in two preclinical mouse models of dMMR cancer, focusing on immune-modulatory effects of either treatment. Abemaciclib monotherapy significantly prolonged overall survival of Mlh1^−/− and Msh2^{loxP/loxP;TgTg(Vil1-cre)} mice (Mlh1^−/−: 14.5 wks vs. 9.0 wks (α-PD-L1), and 3.5 wks (control); Msh2^{loxP/loxP;TgTg(Vil1-cre)}: 11.7 wks vs. 9.6 wks (α-PD-L1), and 2.0 wks (control)). The combination was not superior to either monotherapy. PET/CT imaging revealed individual response profiles, with best clinical responses seen with abemaciclib mono- and combination therapy. Therapeutic effects were accompanied by increasing numbers of tumor-infiltrating CD4⁺/CD8⁺ T-cells and lower numbers of M2-macrophages. Levels of T cell exhaustion markers and regulatory T cell counts declined. Expression analysis identified higher numbers of dendritic cells and neutrophils within tumors together with high expression of DNA damage repair genes as part of the global stress response. In Mlh1^−/− tumors, abemaciclib suppressed the PI3K/Akt pathway and led to induction of Mxd4/Myc. The immune-modulatory potential of abemaciclib renders this compound ideal for dMMR patients not eligible for ICI treatment.

Association Between Cancer-Related Fatigue and Falls in Patients With Myeloproliferative Neoplasms: Results of a Multicenter Cross-Sectional Survey From the East German Study Group for Hematology and Oncology (OSHO #97)

OBJECTIVE

This study retrospectively examined the association between cancer-related fatigue (CrF) and the number of falls during the last 12 months in patients with myeloproliferative neoplasms (MPNs).

METHODS

A multicenter, 1-time anonymous survey was conducted using analog and digital questionnaires. Sex-stratified multinomial logistic regression analysis was applied to investigate the association between CrF and number of falls. All analyses were adjusted for age, school education, body mass index, MPN subtype, and quality of life.

RESULTS

The final sample comprised 688 patients (mean age 57.4 ± 13.8, 62.4% women). The fall rate was 16.2% in women and 12.2% in men (P = .153). There were no differences between women and men in terms of CrF between individuals with more than 1 fall, whereas women with 1 fall had a higher CrF compared to those without a fall (RRR = 1.019; 95% CI [1.002-1.039]), respectively.

CONCLUSION

CrF increases the risk of falls in women with MPN. Physicians should evaluate and manage CrF symptoms and implement fall prevention strategies for those who are at increased risk. Further research is needed to better understand the effects of CrF on gait performance and associated fall risk.

Versorgungsforschung im letzten Lebensjahr

Mit den Fortschritten der Medizin und dem demographischen Wandel wird nicht nur die Lebensspanne in der Bevölkerung verlängert, sondern bei dem zunehmenden Anteil von alten und hochaltrigen Menschen auch immer häufiger die letzte Lebenszeit mit Multimorbidität, Demenz oder mit schweren beeinträchtigenden Erkrankungen verbracht. Daraus resultiert ein wachsender Bedarf an palliativer Versorgung, der auch mit einer zunehmenden Relevanz qualitativ hochwertiger Versorgungsforschung auf diesem Gebiet einhergeht. Über die letzten Jahrzehnte hat die Forschung zu palliativer Versorgung und ihren Besonderheiten enorm zugenommen, so dass mittlerweile ein beachtlicher Korpus an empirischen Erkenntnissen dazu entstanden ist. Eine strukturierte, systematische Übersicht und Bewertung der verwendeten Methoden in diesem Bereich liegt jedoch im deutschsprachigen Raum bisher noch nicht vor. Das Memorandum zur „Versorgungsforschung im letzten Lebensjahr“ will diese Lücke schließen.

[DNVF Memorandum: Health Services Research in the Last Year of Life]

This memorandum outlines current issues concerning health services research on seriously ill and dying people in the last year of their lives as well as support available for their relatives. Patients in the last phase of life can belong to different disease groups, they may have special characteristics (e. g., people with cognitive and complex impairments, economic disadvantage or migration background) and be in certain phases of life (e. g., parents of minor children, (old) age). The need for a designated memorandum on health services research in the last year of life results from the special situation of those affected and from the special features of health services in this phase of life. With reference to these special features, this memorandum describes methodological and ethical specifics as well as current issues in health services research and how these can be adequately addressed using quantitative, qualitative and mixed methods. It has been developed by the palliative medicine section of the German Network for Health Services Research (DNVF) according to the guidelines for DNVF memoranda.

Inhibition of KRAS, MEK and PI3K Demonstrate Synergistic Anti-Tumor Effects in Pancreatic Ductal Adenocarcinoma Cell Lines

Kirsten rat sarcoma virus (KRAS) mutations are widespread in pancreatic ductal adenocarcinoma (PDAC) and contribute significantly to tumor initiation, progression, tumor relapse/resistance, and prognosis of patients. Although inhibitors against KRAS mutations have been developed, this therapeutic approach is not routinely used in PDAC patients. We investigated the anti-tumor efficacy of two KRAS inhibitors BI-3406 (KRAS::SOS1 inhibitor) and sotorasib (KRAS G12C inhibitor) alone or in combination with MEK1/2 inhibitor trametinib and/or PI3K inhibitor buparlisib in seven PDAC cell lines. Whole transcriptomic analysis of combined inhibition and control groups were comparatively analyzed to explore the corresponding mechanisms of inhibitor combination. Both KRAS inhibitors and corresponding combinations exhibited cytotoxicity against specific PDAC cell lines. BI-3406 enhance the efficacy of trametinib and buparlisib in BXPC-3, ASPC-1 and MIA PACA-2, but not in CAPAN-1, while sotorasib enhances the efficacy of trametinib and buparlisib only in MIA PACA-2. The whole transcriptomic analysis demonstrates that the two triple-inhibitor combinations exert antitumor effects by affecting related cell functions, such as affecting the immune system, cell adhesion, cell migration, and cytokine binding. As well as directly involved in RAF/MEK/ERK pathway and PI3K/AKT pathway affect cell survival. Our current study confirmed inhibition of KRAS and its downstream pathways as a potential novel therapy for PDAC and provides fundamental data for in vivo evaluations.

Molecular Characterization of the Response to Conventional Chemotherapeutics in Pro-B-ALL Cell Lines in Terms of Tumor Relapse

Little is known about optimally applying chemotherapeutic agents in a specific temporal sequence to rapidly reduce the tumor load and to improve therapeutic efficacy. The clinical optimization of drug efficacy while reducing side effects is still restricted due to an incomplete understanding of the mode of action and related tumor relapse mechanisms on the molecular level. The molecular characterization of transcriptomic drug signatures can help to identify the affected pathways, downstream regulated genes and regulatory interactions related to tumor relapse in response to drug application. We tried to outline the dynamic regulatory reprogramming leading to tumor relapse in relapsed MLL-rearranged pro-B-cell acute lymphoblastic leukemia (B-ALL) cells in response to two first-line treatments: dexamethasone (Dexa) and cytarabine (AraC). We performed an integrative molecular analysis of whole transcriptome profiles of each treatment, specifically considering public knowledge of miRNA regulation via a network-based approach to unravel key driver genes and miRNAs that may control the relapse mechanisms accompanying each treatment. Our results gave hints to the crucial regulatory roles of genes leading to Dexa-resistance and related miRNAs linked to chemosensitivity. These genes and miRNAs should be further investigated in preclinical models to obtain more hints about relapse processes.

The OUTREACH study: oncologists of German university hospitals in rotation on a palliative care unit-evaluation of attitude and competence in palliative care and hospice

PURPOSE

The effect of the duration of an educational rotation presented at a palliative care unit on the palliative care knowledge gain and the increase of palliative care self-efficacy expectations are unclear.

METHODS

This national prospective multicenter pre-post survey conducted at twelve German University Comprehensive Cancer Centers prospectively enrolled physicians who were assigned to training rotations in specialized palliative care units for three, six, or twelve months. Palliative care knowledge [in %] and palliative care self-efficacy expectations [max. 57 points] were evaluated before and after the rotation with a validated questionnaire.

RESULTS

From March 2018 to October 2020, questionnaires of 43 physicians were analyzed. Physicians participated in a 3- (n = 3), 6- (n = 21), or 12-month (n = 19) palliative care rotation after a median of 8 (0-19) professional years. The training background of rotating physicians covered a diverse spectrum of specialties; most frequently represented were medical oncology (n = 15), and anesthesiology (n = 11). After the rotation, median palliative care knowledge increased from 81.1% to 86.5% (p < .001), and median palliative care self-efficacy expectations scores increased from 38 to 50 points (p < .001). The effect of the 12-month rotation was not significantly greater than that of the 6-month rotation.

CONCLUSION

An educational rotation presented in a specialized palliative care unit for at least six months significantly improves palliative care knowledge and palliative care self-efficacy expectations of physicians from various medical backgrounds.

Relatives Experience More Psychological Distress Due to COVID-19 Pandemic-Related Visitation Restrictions Than In-Patients

Background

The COVID-19 pandemic led to visiting restrictions (VRs) of patients in hospitals. Social contacts between patients' relatives play an important role in convalescence. Isolation may cause new psychological comorbidity. The present study investigated the psychological distress of VR in in-patients and their relatives.

Methods

From April 1, 2020 to May 20, 2020, 313 in-patients (≥14 years) of the University Medical Center Rostock were interviewed by questionnaires and 51 relatives by phone. Subjective psychological distress was assessed by a distress thermometer [0 (not at all)−100 (extreme)]. The study also investigated stressors due to VR, psychological distress in dependence on demographic or disease-related data, currently used communication channels and desired alternatives and support.

Results

Relatives were more psychologically distressed by VR than in-patients (59 ± 34 vs. 38 ± 30, p = 0.002). Loss of direct physical contact and facial expressions/gestures resulted in the most distress. Psychological distress due to VR was independent of demographics and indicates small positive correlations with the severity of physical restriction and the general psychological distress of in-patients. The most frequent ways of communication were via phone and social media. Frequently requested alternatives for patients were other interlocutors and free phone/tablet use, for relatives visiting rooms with partitions.

Conclusion

VRs are a stressor for patients and their relatives. The establishment of visiting rooms with partitions and the free use of phones/tablets could reduce the additional distress.

COVID-19: Challenges and solutions for the provision of care to seriously ill and dying people and their relatives during SARS-CoV-2 pandemic - perspectives of pandemic response team members: A qualitative study on the basis of expert interviews (part of PallPan)

BACKGROUND

During the SARS-CoV-2 pandemic's initial waves, bans on visiting and isolation measures placed limits on providing services for seriously ill and dying people and their relatives. Pandemic response teams at governmental level (macro), at federal state and municipal level (meso) and in healthcare facilities (micro) played their role in pandemic management procedures.

AIM

To explore pandemic-related challenges and solutions of pandemic response teams regarding the provision of care to seriously ill and dying people and their relatives. Findings were to be integrated into a national strategy (PallPan).

DESIGN

Semi-structured expert interviews (10/2020-2/2021) analysed via structured content analysis.

SETTINGPARTICIPANTS

We interviewed 41 members, who discussed the work of 43 German pandemic response teams (micro n = 23; meso n = 20; no members were available at macro level) from 14 German federal states.

RESULTS

Twenty-nine of 43 teams took account of the needs of seriously ill and dying. Their main challenges resulted from pandemic-related legal requirements in hospitals and long-term care facilities. The implementation of such was in the remits of the meso level. Dysfunctional or non-existent communication between the levels was reported to be challenging. To foster patient-related solutions the micro level pandemic response teams supported individual decisions to enable patient-relative contact for example, visiting and saying goodbye outside, meeting via digital solutions.

CONCLUSIONS

Pandemic response teams evidently struggled to find appropriate solutions to ease pandemic-related impact on the care of seriously ill and dying patients and their relatives. We recommend bringing palliative care expertise on board.

Effective tumor cell abrogation via Venetoclax-mediated BCL-2 inhibition in KMT2A-rearranged acute B-lymphoblastic leukemia

Dysregulation of the intrinsic BCL-2 pathway-mediated apoptosis cascade is a common feature of hematological malignancies including acute B-lymphoblastic leukemia (B-ALL). The KMT2A-rearranged high-risk cytogenetic subtype is characterized by high expression of antiapoptotic protein BCL-2, likely due to the direct activating binding of KMT2A fusion proteins to the BCL2 gene. The BCL-2 inhibitor venetoclax (VEN) has proven great clinical value in other blood cancers, however, data on B-ALL is sparse and past studies have not so far described the effects of VEN on gene and protein expression profiles. Using cell lines and patient-derived in vivo xenograft models, we show BCL-2 pathway-mediated apoptosis induction and decelerated tumor cell counts in KMT2A-rearranged B-ALL but not in other cytogenetic subtypes. VEN treatment of cell line- and patient-derived xenografts reduced blast frequencies in blood, bone marrow, and spleen, and tumor cell doubling times were increased. Growth rates are further correlated with VEN concentrations in blood. In vitro incubation with VEN resulted in BCL-2 dephosphorylation and targeted panel RNA sequencing revealed reduced gene expression of antiapoptotic pathway members BCL2, MCL1, and BCL2L1 (BCL-XL). Reinforced translocation of BAX proteins towards mitochondria induced caspase activation and cell death commitment. Prolonged VEN application led to upregulation of antiapoptotic proteins BCL-2, MCL-1, and BCL-XL. Interestingly, the extrinsic apoptosis pathway was strongly modulated in SEM cells in response to VEN. Gene expression of members of the tumor necrosis factor signaling cascade was increased, resulting in canonical NF-kB signaling. This possibly suggests a previously undescribed mechanism of BCL-2-independent and NF-kB-mediated upregulation of MCL-1 and BCL-XL. In summary, we herein prove that VEN is a potent option to suppress tumor cells in KMT2A-rearranged B-ALL in vitro and in vivo. Possible evasion mechanisms, however, must be considered in subsequent studies.

Preclinical Head and Neck Squamous Cell Carcinoma Models for Combined Targeted Therapy Approaches

This study aimed to refine combined targeted approaches on well-characterized, low-passage tumor models. Upon in vivo xenografting in immunodeficient mice, three cell lines from locally advanced or metastatic HNSCC were established. Following quality control and basic characterization, drug response was examined after therapy with 5-FU, Cisplatin, and cyclin-dependent kinase inhibitors (abemaciclib, THZ1). Our cell lines showed different in vitro growth kinetics, morphology, invasive potential, and radiosensitivity. All cell lines were sensitive to 5-FU, Cisplatin, and THZ1. One cell line (HNSCC48 P0 M1) was sensitive to abemaciclib. Here, Cyto-FISH revealed a partial CDKN2a deletion, which resulted from a R58* mutation. Moreover, this cell line demonstrated chromosome 12 polysomy, accompanied by an increase in CDK4-specific copy numbers. In HNSCC16 P1 M1, we likewise identified polysomy-associated CDK4-gains. Although not sensitive to abemaciclib per se, the cell line showed a G1-arrest, an increased number of acidic organelles, and a swollen structure. Notably, intrinsic resistance was conquered by Cisplatin because of cMYC and IDO-1 downregulation. Additionally, this Cisplatin-CDKI combination induced HLA-ABC and PD-L1 upregulation, which may enhance immunogenicity. Performing functional and molecular analysis on patient-individual HNSCC-models, we identified CDK4-gains as a biomarker for abemaciclib response prediction and describe an approach to conquer intrinsic CDKI resistance.

Spirooxindol‐1,3‐oxazine alkaloids: highly potent and selective antitumor agents evolved from iterative structure optimization

Spirooxindole‐1,3‐oxazines are a small and structurally unique class of spirooxindole alkaloids. To date, only four of these compounds have been isolated from natural sources, and their biological properties remained unknown thus far. Dioxyreserpine is a synthetic spirooxindole‐1,3‐oxazine, that can readily be prepared from the Rauvolfia alkaloid (–)‐reserpine by catalytic photooxygenation. While dioxyreserpine itself was now identified as a moderately effective antitumoral agent, structurally modified analogs of it emerged as a new class of highly potent and selective growth inhibitors of various human cancers, including pancreatic cancers. Systematic structural optimization ultimately led to an inhibitor displaying low‐micromolar IC₅₀‐values against six cancer cell lines as well as selective apoptosis induction in vitro.

Inhibitory Response to CK II Inhibitor Silmitasertib and CDKs Inhibitor Dinaciclib Is Related to Genetic Differences in Pancreatic Ductal Adenocarcinoma Cell Lines

Casein kinase II (CK2) and cyclin-dependent kinases (CDKs) frequently interact within multiple pathways in pancreatic ductal adenocarcinoma (PDAC). Application of CK2- and CDK-inhibitors have been considered as a therapeutic option, but are currently not part of routine chemotherapy regimens. We investigated ten PDAC cell lines exposed to increasing concentrations of silmitasertib and dinaciclib. Cell proliferation, metabolic activity, biomass, and apoptosis/necrosis were evaluated, and bioinformatic clustering was used to classify cell lines into sensitive groups based on their response to inhibitors. Furthermore, whole exome sequencing (WES) and RNA sequencing (RNA-Seq) was conducted to assess recurrent mutations and the expression profile of inhibitor targets and genes frequently mutated in PDAC, respectively. Dinaciclib and silmitasertib demonstrated pronounced and limited cell line specific effects in cell death induction, respectively. WES revealed no genomic variants causing changes in the primary structure of the corresponding inhibitor target proteins. RNA-Seq demonstrated that the expression of all inhibitor target genes was higher in the PDAC cell lines compared to non-neoplastic pancreatic tissue. The observed differences in PDAC cell line sensitivity to silmitasertib or dinaciclib did not depend on target gene expression or the identified gene variants. For the PDAC hotspot genes kirsten rat sarcoma virus (KRAS) and tumor protein p53 (TP53), three and eight variants were identified, respectively. In conclusion, both inhibitors demonstrated in vitro efficacy on the PDAC cell lines. However, aberrations and expression of inhibitor target genes did not appear to affect the efficacy of the corresponding inhibitors. In addition, specific aberrations in TP53 and KRAS affected the efficacy of both inhibitors.

The Inhibitory Response to PI3K/AKT Pathway Inhibitors MK-2206 and Buparlisib Is Related to Genetic Differences in Pancreatic Ductal Adenocarcinoma Cell Lines

The aberrant activation of the phosphoinositide 3-kinase (PI3K)/ protein kinase B (AKT) pathway is common in pancreatic ductal adenocarcinomas (PDAC). The application of inhibitors against PI3K and AKT has been considered as a therapeutic option. We investigated PDAC cell lines exposed to increasing concentrations of MK-2206 (an AKT1/2/3 inhibitor) and Buparlisib (a pan-PI3K inhibitor). Cell proliferation, metabolic activity, biomass, and apoptosis/necrosis were evaluated. Further, whole-exome sequencing (WES) and RNA sequencing (RNA-seq) were performed to analyze the recurrent aberrations and expression profiles of the inhibitor target genes and the genes frequently mutated in PDAC (Kirsten rat sarcoma virus (KRAS), Tumor protein p53 (TP53)). MK-2206 and Buparlisib demonstrated pronounced cytotoxic effects and limited cell-line-specific effects in cell death induction. WES revealed two sequence variants within the direct target genes (PIK3CA c.1143C > G in Colo357 and PIK3CD c.2480C > G in Capan-1), but a direct link to the Buparlisib response was not observed. RNA-seq demonstrated that the expression level of the inhibitor target genes did not affect the efficacy of the corresponding inhibitors. Moreover, increased resistance to MK-2206 was observed in the analyzed cell lines carrying a KRAS variant. Further, increased resistance to both inhibitors was observed in SU.86.86 carrying two TP53 missense variants. Additionally, the presence of the PIK3CA c.1143C > G in KRAS-variant-carrying cell lines was observed to correlate with increased sensitivity to Buparlisib. In conclusion, the present study reveals the distinct antitumor effects of PI3K/AKT pathway inhibitors against PDAC cell lines. Aberrations in specific target genes, as well as KRAS and TP53, individually or together, affect the efficacy of the two PI3K/AKT pathway inhibitors.

Longitudinal Humoral and Cellular Immune Responses Following SARS-CoV-2 Vaccination in Patients with Myeloid and Lymphoid Neoplasms Compared to a Reference Cohort: Results of a Prospective Trial of the East German Study Group for Hematology and Oncology (OSHO)

Purpose: To assess humoral responses longitudinally and cellular immunogenicity following SARS-CoV-2-vaccination in patients with hematologic and oncologic malignancies receiving checkpoint-inhibitors. Methods: This prospective multicenter trial of the East-German-Study-Group-for-Hematology-and-Oncology, enrolled 398 adults in a two (patients; n = 262) to one (controls; n = 136) ratio. Pre-vaccination, day 35 (d35), and day 120 (d120) blood samples were analyzed for anti-spike antibodies and d120 IL-2+IFNγ+TNFα+-CD4+- and CD8+-cells. Laboratories were blinded for patients and controls. Results: Patients belonged to the myeloid (n = 131), lymphoid (n = 104), and checkpoint-inhibitor (n = 17) cohorts. While d35 seroconversion was higher in controls (98%) compared to patients (68%) (p < 0.001), d120 seroconversion improved across all patient cohorts [checkpoint-inhibitors (81% to 100%), myeloid (82% to 97%), lymphoid (48% to 66%)]. CD4+- and CovCD8+-cells in the lymphoid (71%/31%) and control (74%/42%) cohorts were comparable but fewer in the myeloid cohort (53%, p = 0.003 /24%, p = 0.03). In patients with hematologic malignancies, no correlation between d120 humoral and cellular responses was found. A sizeable fraction of lymphoid patients demonstrated T-cell responses without detectable spike-specific-IgGs. Conclusions: Evidence of vaccine-elicited humoral and/or cellular immunogenicity in most patients is provided. Both humoral and cellular responses are crucial to determine which patients will generate/maintain immunity. The findings have implications on public health policy regarding recommendations for SARS-CoV-2 booster doses.

Establishment and Characterization of FusionRed Stable Transfected Canine Prostate Adenocarcinoma and Transitional Cell Carcinoma Cells

BACKGROUND/AIM

Cancer cell inoculation is routinely used to evaluate novel therapeutic approaches in vivo. However, without reporter genes enabling deep tissue imaging, study of early tumor progression and therapeutic responses is often limited. We describe the establishment and characterization of two canine cancer cell lines stably expressing red fluorescence proteins as tools for later in vivo imaging.

MATERIALS AND METHODS

Two red fluorescence cell lines were generated by plasmid transfection. Fluorescence protein expression was confirmed by flow cytometry and microscopy. Deep tissue imaging was demonstrated in mice using a NightOWL LB 983. Gene expression changes after transfection were analyzed by RNAseq.

RESULTS

Both cell lines were detectable in vivo by subcutaneous injection of 1×106 cells. RNAseq revealed up to 2005 transfection-induced differentially expressed genes but no significant changes in cellular key pathways.

CONCLUSION

The fluorescent cell lines provide a solid basis for future in vivo studies on canine cancer.

Role and responsibility of oncologists in assisted suicide. Practice and views among members of the German Society of Haematology and Medical Oncology

Background

Physician-assisted suicide (PAS) is a controversial practice and regulatory frameworks differ regarding assigned physicians' roles. This study explores clinical experience and views of German oncologists concerning ethically and legally relevant aspects of PAS after change of the law.

Materials and methods

An online survey was conducted among members of the German Society of Haematology and Medical Oncology (DGHO) in March 2021. Descriptive analysis, bivariate and multivariable logistic regression of quantitative data on determinants related to (un)willingness to assist with suicide as well qualitative analysis of free-text comments were carried out.

Results

Seven hundred and forty-five of 3588 DGHO members responded (20.8%). Of these, 29.9% reported requests for a lethal drug and 3.0% (n = 22) reported to have assisted with suicide. Almost half of them (47.0%, n = 350) objected to providing PAS, whereas 45.9% indicated a willingness at least under certain conditions. Of those respondents who did not object to PAS, 25.4% would also consider assistance if those willing to die had a psychiatric disease and 10.2% if requestors had no disease at all. A majority viewed a role for physicians regarding different tasks associated with assisted suicide. Respondents with <10 years of professional experience, working in hospital with religious affiliation and with subspecialisation in palliative care were significantly less frequently willing to assist suicide.

Conclusions

Respondents are divided in their personal attitudes towards PAS but a majority supports involvement of physicians regarding different tasks related to assisted suicide. Data about the practice and envisaged professional role may inform development of an acceptable ethico-legal framework for a controversial practice.

•

In Germany, as in other countries, assisted suicide has become lawful more recently.

•

To be able to develop guidance on the highly controversial subject, empirical data on practice and related aspects are needed.

•

30% of responding oncologists report requests for lethal drugs by their patients and 3% have assisted with suicide.

•

Compared with 2015, significantly more oncologists report requests for lethal drugs and willingness to assist with suicide.

•

Palliative care qualification and less professional experience were negatively associated with willingness to assist suicide.

Engraftment Effects after Intra-Bone Marrow versus Intravenous Allogeneic Stem Cell Transplantation in a Reduced-Intensity Conditioning Dog Leukocyte Antigen-Identical Canine Model

Following conventional i.v. hematopoietic stem cell transplantation (IV-HSCT), most of the hematopoietic stem cells get trapped in peripheral organs and do not reach the bone marrow niche. A promising approach to overcome this cell loss during the homing process seems to be the infusion of hematopoietic stem cells directly into the bone marrow cavity (intra-bone marrow [IBM]-HSCT). This study aimed to investigate the engraftment efficiency of IBM-HSCT compared with IV-HSCT following reduced-intensity conditioning in a canine HSCT model. Furthermore, the impact of 2 different graft infusion rates during IBM-HSCT on the engraftment was evaluated. Dogs received 4.5 Gy total body irradiation for conditioning at day -1 and 15 mg/kg cyclosporin A twice daily at days -1 to +35 as immunosuppression. The IV-HSCT group (n = 7) received unmodified bone marrow. The IBM-HSCT cohorts received buffy coat-enriched bone marrow that was applied into the humerus and femur simultaneously with an infusion time of either 10 minutes (IBM10; n = 8) or 60 minutes (IBM60; n = 7). Statistical analyses were performed using the Kruskal-Wallis test followed by the Mann-Whitney U test with Bonferroni correction for multiple comparisons. Statistical significance was declared at Bonferroni-adjusted P < .017. All dogs initially engrafted. One dog of the IBM10 cohort died at day +15 from infection. All 21 evaluable dogs developed a durable mixed donor chimerism over the course of 112 days. Engraftment kinetics did not differ significantly across the 3 groups. Leukocyte and platelet nadirs, as well as the durations of leukopenia and thrombocytopenia, were comparable in the 3 groups. Signs of toxicity for ingestion, body temperature, activity, and defecation did not show statistically significant differences among the 3 groups; only weight loss was greater in the IBM60 group compared with the IV group. IBM-HSCT following reduced-intensity conditioning resulted in an engraftment efficiency and hematopoietic recovery comparable to that seen with conventional IV-HSCT. In addition, modification of the graft infusion rate had no impact on engraftment and hematopoietic recovery in the canine IBM-HSCT model.

Novel chemotherapeutic agent FX-9 activates NF-κB signaling and induces G1 phase arrest by activating CDKN1A in a human prostate cancer cell line

Background

The aminoisoquinoline FX-9 shows pro-apoptotic and antimitotic effects against lymphoblastic leukemia cells and prostate adenocarcinoma cells. In contrast, decreased cytotoxic effects against non-neoplastic blood cells, chondrocytes, and fibroblasts were observed. However, the actual FX-9 molecular mode of action is currently not fully understood.

Methods

In this study, microarray gene expression analysis comparing FX-9 exposed and unexposed prostate cancer cells (PC-3 representing castration-resistant prostate cancer), followed by pathway analysis and gene annotation to functional processes were performed. Immunocytochemistry staining was performed with selected targets.

Results

Expression analysis revealed 0.83% of 21,448 differential expressed genes (DEGs) after 6-h exposure of FX-9 and 0.68% DEGs after 12-h exposure thereof. Functional annotation showed that FX-9 primarily caused an activation of inflammatory response by non-canonical nuclear factor-kappa B (NF-κB) signaling. The 6-h samples showed activation of the cell cycle inhibitor CDKN1A which might be involved in the secondary response in 12-h samples. This secondary response predominantly consisted of cell cycle-related changes, with further activation of CDKN1A and inhibition of the transcription factor E2F1, including downstream target genes, resulting in G1-phase arrest. Matching our previous observations on cellular level senescence signaling pathways were also found enriched. To verify these results immunocytochemical staining of p21 Waf1/Cip1 (CDKN1A), E2F1 (E2F1), PAI-1 (SERPNE1), and NFkB2/NFkB p 100 (NFKB2) was performed. Increased expression of p21 Waf1/Cip1 and NFkB2/NFkB p 100 after 24-h exposure to FX-9 was shown. E2F1 and PAI-1 showed no increased expression.

Conclusions

FX-9 induced G1-phase arrest of PC-3 cells through activation of the cell cycle inhibitor CDKN1A, which was initiated by an inflammatory response of noncanonical NF-κB signaling.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08836-y.

Allogeneic hematopoietic stem cell transplantation improves long-term outcome for relapsed AML patients across all ages: results from two East German Study Group Hematology and Oncology (OSHO) trials

Relapse of acute leukemia is a frequent complication with uncertain outcome and poorly defined risk factors. From 1621 patients entered into two prospective clinical trials (AML02; n = 740 and AML04; n = 881), 74.2% reached complete remission (CR) 1 after induction(s) and 59 patients after additional induction ± hematopoietic cell transplantation (HCT). Of the non-refractory patients, 48.4% with a median age of 63 (range 17-85) years relapsed. Relapses occurred within 6 months after CR in 46.5%, between 7 and 18 months in 38.7%, and after 18 months in 14.8% of patients. Relapse treatment resulted in CR2 in 39% of patients depending upon age (54.5% of ≤ 60 and 28.6% of > 60 years), duration of CR1, and treatment of relapse. Overall survival (OS) was 10.9 (7.4-16.2) %, but OS after HCT ± intensive chemotherapy (ICT) was 39.3% (31.8-48.6) at 5 years and not different in younger and older patients. Donor lymphocyte infusion ± chemotherapy and ICT alone resulted only in OS of 15.4% and of 5%, respectively. Independent favorable factors for OS were long CR1 duration, and HCT, while non-monosomal disease was beneficial for OS in elderly patients. Leukemia-free survival [LFS; 24.9 (19.5-31.7) % at 10 years] was affected by similar risk factors. In a competing risk model, the relapse incidence at 5 years was 53.5 ± 3.5% and the non-relapse mortality rate 21.7 ± 2.9%. Lower relapse incidence was observed in patents with HCT, long CR1 duration, and female gender. Risk factors for non-relapse mortality were HCT in younger and type of AML in elderly patients. In conclusion, allogeneic HCT ± IC improved the results in relapsed AML in younger and elderly patients. Increasing CR2 rates and HCT frequency will be the challenge for the next years. Relapse of the disease remains the major problem.

Long-term survivor of metastatic squamous-cell head and neck carcinoma with occult primary after cetuximab-based chemotherapy: A case report

BACKGROUND

Cancer of unknown primary (CUP) is a histological proven malignant tumor whose origin cannot be detected despite careful examination. Most cervical lymph node metastases in CUP (80%) will originate from head and neck sites, and 15% show infiltration of squamous carcinoma cells. The survival rates of CUP are poor: The 5-year-survival rate ranges from 10% to 15%. First-line treatment recommendation for advanced, inoperable squamous cell carcinoma of head/neck (HNSCC) was cetuximab plus platinum-fluorouracil chemotherapy until recently, when checkpoint inhibitors proved clinically beneficial therapies.

CASE SUMMARY

Here, we report a case of a 42-year-old female patient with cervical and abdominal lymph node and distant bone metastases of an occult primary of the head and neck (squamous cell carcinoma, human papillomavirus positive). The cancer was diagnosed during pregnancy 10 years ago, and after giving birth, the patient was treated with cetuximab plus platinum-fluorouracil chemotherapy achieving complete remission (CR). CR lasted 26 mo when new metastases (abdominal lymph node, lumbar vertebral body) emerged. Both manifestations were irradiated. From then on, the patient has not received any further treatment, and her disease has remained controlled. Ten years after the initial cancer diagnosis, the patient is still alive and in good health, representing an exceptional case of HNSCC.

CONCLUSION

This case illustrates the exceptional clinical course and benefits of combined therapy approaches in advanced metastatic HNSCC with occult primary.

Establishment and characterization of patient-derived head and neck cancer models from surgical specimens and endoscopic biopsies

Background

Head and neck squamous cell carcinoma (HNSCC) is heterogeneous in etiology, phenotype and biology. Patient-derived xenografts (PDX) maintain morphology and molecular profiling of the original tumors and have become a standard “Avatar” model for human cancer research. However, restricted availability of tumor samples hindered the widespread use of PDX. Most PDX-projects include only surgical specimens because reliable engraftment from biopsies is missing. Therefore, sample collection is limited and excludes recurrent and metastatic, non-resectable cancer from preclinical models as well as future personalized medicine.

Methods

This study compares the PDX-take rate, -growth, histopathology, and molecular characteristics of endoscopic specimens with surgical specimens. HNSCC samples (n = 55) were collected ad hoc, fresh frozen and implanted into NOD.Cg-Prkdc^scidIl2rg^tm1Wjl/SzJ mice.

Results

Engraftment was successful in both sample types. However, engraftment rate was lower (21 vs. 52%) and growth delayed (11.2 vs. 6.7 weeks) for endoscopic biopsies. Following engraftment, growth kinetic was similar. Comparisons of primary tumors and corresponding PDX models confirmed preservation of histomorphology (HE histology) and molecular profile (Illumina Cancer Hotspot Panel) of the patients’ tumors. Accompanying flow cytometry on primary tumor specimens revealed a heterogeneous tumor microenvironment among individual cases and identified M2-like macrophages as positive predictors for engraftment. Vice versa, a high PD-L1 expression (combined positive score on tumor/immune cells) predicted PDX rejection.

Conclusion

Including biopsy samples from locally advanced or metastatic lesions from patients with non-surgical treatment strategies, increases the availability of PDX for basic and translational research. This facilitates (pre-) clinical studies for individual response prediction based on immunological biomarkers.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13046-021-02047-w.

Histopathological Features and Ann Arbor Stage in Periocular Lymphoma

BACKGROUND

To evaluate biodata, symptoms/signs, lymphoma type, localization, stage level, treatment choice and outcome of ocular adnexal lymphoma (OAL).

PATIENTS AND METHODS

A single-center retrospective analysis of 56 patients with OAL was performed from 1998 to 2018.

RESULTS

OAL involved the orbit in 44.6%, the conjunctiva in 32.1%, the lacrimal apparatus in 14.3% and the eyelid in 8.93%. Extranodal marginal zone B-cell lymphoma (EMZL) was found in 60.7%, follicular lymphoma (FL) in 21.4%, diffuse large B-cell lymphoma in 7.14%, mantle cell lymphoma in 5.36% and chronic lymphatic leukaemia in 5.36% patients. No relapse was seen in 76%. EMZL and FL had a significantly better overall survival compared to other lymphoma types (p=0.002). Patients with Ann Arbor stage IE had a significantly better prognosis than those with stages higher than IE (p=0.048).

CONCLUSION

Our data suggest that clinicopathological features such as Ann Arbor stage influence survival.

FOLFOX plus panitumumab or FOLFOX alone as additive therapy following R0/1 resection of RAS wild-type colorectal cancer liver metastases: The PARLIM trial (AIO KRK 0314)

3553

Background: This trial investigates the addition of panitumumab to chemotherapy with fluorouracil/ folinic acid and oxaliplatin (FOLFOX) in a 2:1 randomized, controlled, open label, phase II trial in RAS wild-type colorectal cancer patients with R0/1-resected liver metastases. Methods: The primary endpoint was progression-free survival (PFS) two years after randomisation. The experimental arm (12 wks of biweekly mFOLFOX6 plus panitumumab followed by 12 wks of panitumumab alone) was considered active if the 2-year-PFS rate was ≥65%. Based on historical data, a 2-year-PFS rate of 50% was estimated in the control arm (12 wks of biweekly FOLFOX). The trial was performed with a power of 80% and an alpha of 0.05. Secondary endpoints included overall survival (OS) and toxicity. The trial is registered with ClinicalTrials.gov, NCT01384994. Results: The full analysis set consists of 70 patients (pts) in the experimental arm and 36 pts in the control arm. The 2-year-PFS rate was 34.3% with FOLFOX plus panitumumab and failed to meet the primary endpoint. The 2-year-PFS rate in the control arm was 25%. In the experimental arm, a more favourable outcome was observed with regard to PFS (HR: 0.72, 95%CI 0.45-1.17; P = 0.18) and OS (HR: 0.76 (95% CI 0.34-1.71, P = 0.51) which did, however, not reach the level of significance. Updated data including toxicity and subgroup analyses might be presented at the meeting Conclusions: The PARLIM trial clearly failed to demonstrate a PFS rate of 65% after resection of colorectal liver metastases 2 years after randomisation, potentially indicating that the generally high frequency of recurrence and the choice of primary endpoint did not correspond in this study population. However, a trend for improved PFS and OS by the addition of panitumumab to 12 wks of FOLFOX followed by 12 wks panitumumab maintenance therapy may support future trials with ant-EGFR antibodies in this specific treatment setting. Clinical trial information: NCT01384994.

The Individual Effects of Cyclin-Dependent Kinase Inhibitors on Head and Neck Cancer Cells-A Systematic Analysis

Cyclin-dependent kinase inhibitors (CDKi´s) display cytotoxic activity against different malignancies, including head and neck squamous cell carcinomas (HNSCC). By coordinating the DNA damage response, these substances may be combined with cytostatics to enhance cytotoxicity. Here, we investigated the influence of different CDKi´s (palbociclib, dinaciclib, THZ1) on two HNSCC cell lines in monotherapy and combination therapy with clinically-approved drugs (5-FU, Cisplatin, cetuximab). Apoptosis/necrosis, cell cycle, invasiveness, senescence, radiation-induced γ-H2AX DNA double-strand breaks, and effects on the actin filament were studied. Furthermore, the potential to increase tumor immunogenicity was assessed by analyzing Calreticulin translocation and immune relevant surface markers. Finally, an in vivo mouse model was used to analyze the effect of dinaciclib and Cisplatin combination therapy. Dinaciclib, palbociclib, and THZ1 displayed anti-neoplastic activity after low-dose treatment, while the two latter substances slightly enhanced radiosensitivity. Dinaciclib decelerated wound healing, decreased invasiveness, and induced MHC-I, accompanied by high amounts of surface-bound Calreticulin. Numbers of early and late apoptotic cells increased initially (24 h), while necrosis dominated afterward. Antitumoral effects of the selective CDKi palbociclib were weaker, but combinations with 5-FU potentiated effects of the monotherapy. Additionally, CDKi and CDKi/chemotherapy combinations induced MHC I, indicative of enhanced immunogenicity. The in vivo studies revealed a cell line-specific response with best tumor growth control in the combination approach. Global acting CDKi's should be further investigated as targeting agents for HNSCC, either individually or in combination with selected drugs. The ability of dinaciclib to increase the immunogenicity of tumor cells renders this substance a particularly interesting candidate for immune-based oncological treatment regimens.

Longitudinal observation of anxiety and depression among palliative care cancer patients

BACKGROUND

Anxiety and depressive symptoms are commonly reported to have a high prevalence in advanced cancer patients. However, whether the severity of the symptoms change during a stay in a palliative care unit (PCU) and after discharge home has not been studied thus far. This prospective, longitudinal, single-center study screened for anxiety and depression as measured on the German version of Hospital Anxiety and Depression Scale (HADS-D) in a palliative care (PC) cancer cohort at three different time points.

METHODS

Consecutive patients (N=206) admitted to a PCU were evaluated of whom N=102 could be enrolled. Patients were screened for anxiety and depression using the HADS-D questionnaire: 24 h after admittance (P1), within 24 h before discharge (P2) and 2 weeks after discharge (P3). Longitudinal changes and influencing factors were determined.

RESULTS

Nearly 80% of all patients had at least at one time point a HADS score ≥8 indicating a clinically meaningful symptom burden. The P1 mean scores were 7.1±3.3 (anxiety) and 8.9±4.6 (depression). Depression was associated with underlying cancer type (P<0.05). Anxiety and depression stabilized during hospitalization (P2). However, a significant deterioration after discharge (P3) was observed (anxiety P=0.046; depression P=0.003), in particular in older patients (>65 years) and higher ECOG status (≥3). Patients with a short time since first diagnosis (<1 year) had significantly higher symptom burden compared to patients with a longer disease course. Participation was 50% emphasizing the difficulty to study PC patients. Most patients had advanced cancers (99%). Underlying cancer types consisted of a broad variety of solid tumors including 15% hematological cases. Median survival was 1.1 months.

CONCLUSIONS

The high prevalence of anxiety and depressive symptoms points to the need for psychological support. All PC patients should be screened for psychological distress to identify those in need of further assessment and treatment. The deterioration at home suggests the need for improved outpatient management, including home-based psychological support. Caregivers should be aware of the psychological vulnerability of newly diagnosed cancer patients, patients with lower functional status and higher age.

Cyclin-dependent kinase inhibitors in head and neck cancer and glioblastoma-backbone or add-on in immune-oncology?

Cyclin-dependent kinases (CDK) control the cell cycle and play a crucial role in oncogenesis. Pharmacologic inhibition of CDK has contributed to the recent clinical approval of dual CDK4/6 inhibitors for the treatment of breast and small cell lung cancer. While the anticancer cell effects of CDK inhibitors are well-established, preclinical and early clinical studies describe additional mechanisms of action such as chemo- and radiosensitization or immune stimulation. The latter offers great potential to incorporate CDK inhibitors in immune-based treatments. However, dosing schedules and accurate timing of each combination partner need to be respected to prevent immune escape and resistance. In this review, we provide a detailed summary of CDK inhibitors in the two solid cancer types head and neck cancer and glioblastoma multiforme; it describes the molecular mechanisms of response vs. resistance and covers strategies to avoid resistance by the combination of immunotherapy or targeted therapy.

PDA Indolylmaleimides Induce Anti-Tumor Effects in Prostate Carcinoma Cell Lines Through Mitotic Death

Castrate resistant prostate cancer in men shares several characteristics with canine prostate cancer (PCa). Due to current insufficient therapies, evaluating novel therapeutic agents for late-stage PCa is of considerable interest for both species. PDA indolylmaleimides showed anticancer effects in several neoplastic cell lines. Herein, a comparative characterization of PDA-66 and PDA-377 mediated effects was performed in human and canine PCa cell lines, which is also the first detailed characterization of these agents on cells derived from solid tumors in general. While PDA-377 showed only weak growth inhibition on human PCa cell lines, PDA-66 inhibited proliferation and induced apoptosis in human and canine cell lines with concentrations in the low micromolar range. Morphological characterization and whole transcriptome sequencing revealed that PDA-66 induces mitotic death through its microtubule-depolymerizing ability. PDA-66 appears to be a worthwhile anti-mitotic agent for further evaluation. The similarities in cellular and molecular response observed in the cell lines of both origins form a solid basis for the use of canine PCa in vivo models to gain valuable interchangeable data to the advantage of both species.

Aortic valve and coronary artery bypass surgery in a patient with factor VII deficiency

Congenital factor VII (FVII) deficiency is a rare bleeding disorder (RBD) with phenotypes ranging from asymptomatic state to life threatening bleeding episodes. There is no established recommendation for the perioperative management of patients scheduled for cardiac surgery. We have described the perioperative management of a patient with FVII deficiency treated for aortic valve stenosis, coronary artery disease, and atrial fibrillation. Balancing perioperative bleeding risk and risks of thrombotic events thereafter in such patients is difficult and requires a multidisciplinary approach.

Towards biomarkers for outcomes after pancreatic ductal adenocarcinoma and ischaemic stroke, with focus on (co)-morbidity and ageing/cellular senescence (SASKit): protocol for a prospective cohort study

INTRODUCTION

Ageing-related processes such as cellular senescence are believed to underlie the accumulation of diseases in time, causing (co)morbidity, including cancer, thromboembolism and stroke. Interfering with these processes may delay, stop or reverse morbidity. The aim of this study is to investigate the link between (co)morbidity and ageing by exploring biomarkers and molecular mechanisms of disease-triggered deterioration in patients with pancreatic ductal adenocarcinoma (PDAC) and (thromboembolic) ischaemic stroke (IS).

METHODS AND ANALYSIS

We will recruit 50 patients with PDAC, 50 patients with (thromboembolic) IS and 50 controls at Rostock University Medical Center, Germany. We will gather routine blood data, clinical performance measurements and patient-reported outcomes at up to seven points in time, alongside in-depth transcriptomics and proteomics at two of the early time points. Aiming for clinically relevant biomarkers, the primary outcome is a composite of probable sarcopenia, clinical performance (described by ECOG Performance Status for patients with PDAC and the Modified Rankin Scale for patients with stroke) and quality of life. Further outcomes cover other aspects of morbidity such as cognitive decline and of comorbidity such as vascular or cancerous events. The data analysis is comprehensive in that it includes biostatistics and machine learning, both following standard role models and additional explorative approaches. Prognostic and predictive biomarkers for interventions addressing senescence may become available if the biomarkers that we find are specifically related to ageing/cellular senescence. Similarly, diagnostic biomarkers will be explored. Our findings will require validation in independent studies, and our dataset shall be useful to validate the findings of other studies. In some of the explorative analyses, we shall include insights from systems biology modelling as well as insights from preclinical animal models. We anticipate that our detailed study protocol and data analysis plan may also guide other biomarker exploration trials.

ETHICS AND DISSEMINATION

The study was approved by the local ethics committee (Ethikkommission an der Medizinischen Fakultät der Universität Rostock, A2019-0174), registered at the German Clinical Trials Register (DRKS00021184), and results will be published following standard guidelines.

Ultradeep targeted sequencing reveals low allele frequencies of somatic JAK2 and MPL variants in patients with abdominal vein thromboses: results of an ongoing prospective prevalence study in Mecklenburg-West Pomerania

Myeloproliferative neoplasms are characterized by mutations in JAK2, MPL and CALR genes. Commonly in diagnostics and previous studies mainly sequencing and common PCR techniques under conventional detection limits are used.

Splanchnic vein thromboses are rare, but often appear associated with myeloproliferative neoplasms and represent serious complications.

Herein, blood from patients with abdominal vein thromboses in Mecklenburg-West Pomerania (federal district of northern Germany), included in an ongoing prospective prevalence study, was analyzed by next generation sequencing representing the complete protein coding regions of JAK2, MPL and CALR genes with a coverage of > 2000 reads, therefore an ultradeep targeting approach.

JAK2 V617F mutations were detected in 11/44 patients. In four of these cases allele frequencies ranged below the conventional cut off of 2%. MPL W515R was detected in 3/44 cases in low frequencies.

Very low allele frequencies of JAK2 and MPL variants in patients with abdominal vein thromboses may indicate early manifestations of myeloproliferative neoplasms.

Use of letermovir in off-label indications: Infectious Diseases Working Party of European Society of Blood and Marrow Transplantation retrospective study

Letermovir (LMV) is licensed for prophylaxis of CMV infection in allogeneic hematopoietic cell transplant adult CMV-seropositive patients. Due to its favorable safety profile, LMV brings potential for use in other clinical situations, outside the approved indication. The objective of the study was to analyze the efficacy and safety of the use of LMV in off-label indications in EBMT centers. A total of 49 patients were reported including 44 adults and 5 children. LMV was administered for: secondary prophylaxis (37 adults, 3 children), primary prophylaxis (2 children), pre-emptive treatment (5 adults), and therapy of CMV disease (2 adults; pneumonia, colitis). Cyclosporine was concomitantly used in 26 patients. Overall, LMV was used for a median 112 days (range: 10-473). Cumulative incidence of breakthrough infections during secondary prophylaxis was 10.1% (95% CI = 3.1-21.9). Prophylactic treatment with LMV resulted in 94.9% (95% CI = 81.0-98.7), and 81.9% (95% CI = 65.7-90.9) probability of, respectively, 60 and 120-day survival without CMV infection in patients receiving secondary prophylaxis. During therapy of CMV infection/disease, probability of 60 and 120-day overall survival was 100% and 71.4% (95% CI = 25.8-92.0), respectively. No breakthrough infection occurred in children on LMV prophylaxis. Adverse events were reported in 15/49 (30.4%) patients: the most common being nausea/vomiting (22.4%). In conclusion, the efficacy of the use of LMV as secondary prophylaxis was high, and the preliminary experience with the use of LMV for the treatment of patients with refractory CMV infection/disease was positive. Our data showed that higher dose or prolonged therapy did not result in increased rate of adverse events.

In vivo vaccination with cell line-derived whole tumor lysates: neoantigen quality, not quantity matters

BACKGROUND

Cancer vaccines provide a complex source of neoantigens. Still, increasing evidence reveals that the neoantigen quality rather than the quantity is predictive for treatment outcome.

METHODS

Using the preclinical Mlh1^-/- tumor model, we performed a side-by side comparison of two autologous cell-line derived tumor lysates (namely 328 and A7450 T1 M1) harboring different tumor mutational burden (TMB; i.e. ultra-high: 328; moderate-high: A7450 T1 M1). Mice received repetitive prophylactic or therapeutic applications of the vaccine. Tumor incidence, immune responses and tumor microenvironment was examined.

RESULTS

Both tumor cell lysates delayed tumor formation in the prophylactic setting, with the A7450 T1 M1 lysate being more effective in decelerating tumor growth than the 328 lysate (median overall survival: 37 vs. 25 weeks). Comparable results were achieved in therapeutic setting and could be traced back to antigen-driven immune stimulation. Reactive T cells isolated from A7450 T1 M1-treated mice recognized autologous Mlh1^-/- tumor cells in IFNγ ELISpot, but likewise YAC-1 cells, indicative for stimulation of both arms of the immune system. By deciphering local effects, vaccines shaped the tumor microenvironment differently. While A7450 T1 M1 prophylactically vaccinated tumors harbored low numbers of myeloid-derived suppressor cells (MDSC) and elevated CD8-T cell infiltrates, vaccination with the 328 lysate evoked MDSC infiltration. Similar effects were seen in the therapeutic setting with stable disease induction only upon A7450 T1 M1 vaccination. Untangling individual response profiles revealed strong infiltration with LAG3⁺ and PD-L1⁺ immune cells when treatments failed, but almost complete exclusion of checkpoint-expressing lymphocytes in long-term survivors.

CONCLUSIONS

By applying two tumor cell lysates we demonstrate that neoantigen quality outranks quantity. This should be considered prior to designing cancer vaccine-based combination approaches.

Combination of the PI3K inhibitor Idelalisib with the conventional cytostatics cytarabine and dexamethasone leads to changes in pathway activation that induce anti-proliferative effects in B lymphoblastic leukaemia cell lines

BACKGROUND

The introduction of combined conventional cytostatics and pathway-specific inhibitors has opened new treatment options for several cancer types including hematologic neoplasia such as leukaemias. As the detailed understanding of the combination-induced molecular effects is often lacking, the identification of combination-induced molecular mechanisms bears significant value for the further development of interventional approaches.

METHODS

Combined application of conventional cytostatic agents (cytarabine and dexamethasone) with the PI3K-inhibitor Idelalisib was analysed on cell-biologic parameters in two acute pro-B lymphoblastic leukaemia (B-ALL) cell lines. In particular, for comparative characterisation of the molecular signatures induced by the combined and mono application, whole transcriptome sequencing was performed. Emphasis was placed on pathways and genes exclusively regulated by drug combinations.

RESULTS

Idelalisib + cytostatics combinations changed pathway activation for, e.g., "Retinoblastoma in cancer", "TGF-b signalling", "Cell cycle" and "DNA-damage response" to a greater extent than the two cytostatics alone. Analyses of the top-20 regulated genes revealed that both combinations induce characteristic gene expression changes.

CONCLUSION

A specific set of genes was exclusively deregulated by the drug combinations, matching the combination-specific anti-proliferative cell-biologic effects. The addition of Idelalisib suggests minor synergistic effects which are rather to be classified as additive.