A novel cell line panel reveals non-genetic mediators of platinum resistance and phenotypic diversity in high grade serous ovarian cancer.

OBJECTIVES: Resistance to cancer therapy is an enduring challenge and accurate and reliable preclinical models are lacking. We interrogated this unmet need using high grade serous ovarian cancer (HGSC) as a disease model. METHODS: We created five in vitro and two in vivo platinum-resistant HGSC models and characterised the entire cell panel via whole genome sequencing, RNASeq and creation of intraperitoneal models. RESULTS: Mutational signature analysis indicated that platinum-resistant cell lines evolved from a pre-existing ancestral clone but a unifying mutational cause for drug resistance was not identified. However, cisplatin-resistant and carboplatin-resistant cells evolved recurrent changes in gene expression that significantly overlapped with independent samples obtained from multiple patients with relapsed HGSC. Gene Ontology Biological Pathways (GOBP) related to the tumour microenvironment, particularly the extracellular matrix, were repeatedly enriched in cisplatin-resistant cells, carboplatin-resistant cells and also in human resistant/refractory samples. The majority of significantly over-represented GOBP however, evolved uniquely in either cisplatin- or carboplatin-resistant cell lines resulting in diverse intraperitoneal behaviours that reflect different clinical manifestations of relapsed human HGSC. CONCLUSIONS: Our clinically relevant and usable models reveal a key role for non-genetic factors in the evolution of chemotherapy resistance. Biological pathways relevant to the extracellular matrix were repeatedly expressed by resistant cancer cells in multiple settings. This suggests that recurrent gene expression changes provide a fitness advantage during platinum therapy and also that cancer cell-intrinsic mechanisms influence the tumour microenvironment during the evolution of drug resistance. Candidate genes and pathways identified here could reveal therapeutic opportunities in platinum-resistant HGSC.

Immune checkpoint inhibitor treatment of a first cancer is associated with a decreased incidence of second primary cancer.

BACKGROUND: Second primary cancers (SPCs) are diagnosed in over 5% of patients after a first primary cancer (FPC). We explore here the impact of immune checkpoint inhibitors (ICIs) given for an FPC on the risk of SPC in different age groups, cancer types and treatments. PATIENTS AND METHODS: The files of the 46 829 patients diagnosed with an FPC in the Centre Léon Bérard from 2013 to 2018 were analyzed. Structured data were extracted and electronic patient records were screened using a natural language processing tool, with validation using manual screening of 2818 files of patients. Univariate and multivariate analyses of the incidence of SPC according to patient characteristics and treatment were conducted. RESULTS: Among the 46 829 patients, 1830 (3.9%) had a diagnosis of SPC with a median interval of 11.1 months (range 0-78 months); 18 128 (38.7%) received cytotoxic chemotherapy (CC) and 1163 (2.5%) received ICIs for the treatment of the FPC in this period. SPCs were observed in 7/1163 (0.6%) patients who had received ICIs for their FPC versus 437/16 997 (2.6%) patients receiving CC and no ICIs for the FPC versus 1386/28 669 (4.8%) for patients receiving neither CC nor ICIs for the FPC. This reduction was observed at all ages and for all histotypes analyzed. Treatment with ICIs and/or CC for the FPC are associated with a reduced risk of SPC in multivariate analysis. CONCLUSION: Immunotherapy with ICIs alone and in combination with CC was found to be associated with a reduced incidence of SPC for all ages and cancer types.

European LeukemiaNet 2020 recommendations for treating chronic myeloid leukemia.

The therapeutic landscape of chronic myeloid leukemia (CML) has profoundly changed over the past 7 years. Most patients with chronic phase (CP) now have a normal life expectancy. Another goal is achieving a stable deep molecular response (DMR) and discontinuing medication for treatment-free remission (TFR). The European LeukemiaNet convened an expert panel to critically evaluate and update the evidence to achieve these goals since its previous recommendations. First-line treatment is a tyrosine kinase inhibitor (TKI; imatinib brand or generic, dasatinib, nilotinib, and bosutinib are available first-line). Generic imatinib is the cost-effective initial treatment in CP. Various contraindications and side-effects of all TKIs should be considered. Patient risk status at diagnosis should be assessed with the new EUTOS long-term survival (ELTS)-score. Monitoring of response should be done by quantitative polymerase chain reaction whenever possible. A change of treatment is recommended when intolerance cannot be ameliorated or when molecular milestones are not reached. Greater than 10% BCR-ABL1 at 3 months indicates treatment failure when confirmed. Allogeneic transplantation continues to be a therapeutic option particularly for advanced phase CML. TKI treatment should be withheld during pregnancy. Treatment discontinuation may be considered in patients with durable DMR with the goal of achieving TFR.

A randomised phase II trial of hydroxychloroquine and imatinib versus imatinib alone for patients with chronic myeloid leukaemia in major cytogenetic response with residual disease.

In chronic-phase chronic myeloid leukaemia (CP-CML), residual BCR-ABL1+ leukaemia stem cells are responsible for disease persistence despite TKI. Based on in vitro data, CHOICES (CHlorOquine and Imatinib Combination to Eliminate Stem cells) was an international, randomised phase II trial designed to study the safety and efficacy of imatinib (IM) and hydroxychloroquine (HCQ) compared with IM alone in CP-CML patients in major cytogenetic remission with residual disease detectable by qPCR. Sixty-two patients were randomly assigned to either arm. Treatment 'successes' was the primary end point, defined as ≥0.5 log reduction in 12-month qPCR level from trial entry. Selected secondary study end points were 24-month treatment 'successes', molecular response and progression at 12 and 24 months, comparison of IM levels, and achievement of blood HCQ levels >2000 ng/ml. At 12 months, there was no difference in 'success' rate (p = 0.58); MMR was achieved in 80% (IM) vs 92% (IM/HCQ) (p = 0.21). At 24 months, the 'success' rate was 20.8% higher with IM/HCQ (p = 0.059). No patients progressed. Seventeen serious adverse events, including four serious adverse reactions, were reported; diarrhoea occurred more frequently with combination. IM/HCQ is tolerable in CP-CML, with modest improvement in qPCR levels at 12 and 24 months, suggesting autophagy inhibition maybe of clinical value in CP-CML.

Chronic disseminated candidiasis and acute leukemia: Impact on survival and hematopoietic stem cell transplantation agenda.

OBJECTIVES: To study the management of chronic disseminated candidiasis (CDC) in patients presenting with acute leukemia. PATIENTS AND METHODS: Single-center retrospective study of acute leukemia patients (2006-2015) to investigate three aspects of CDC: its impact on the time interval between diagnosis and hematopoietic stem cell transplantation, when required (non-parametric Wilcoxon-Mann-Whitney test); its impact on overall survival (Cox proportional hazard regression model); antifungal therapeutic strategies implemented. RESULTS: A total of 639 patients presenting with acute leukemia were included; 144 were transplanted and 29 developed CDC. CDC did not significantly increase the time interval between diagnosis and transplantation, nor did it impact the overall survival of recipients. An improved overall survival was observed in non-transplanted acute leukemia patients presenting with CDC. CONCLUSION: CDC should not postpone transplantation if antifungal treatment is optimized.

Revealing stiffening and brittling of chronic myelogenous leukemia hematopoietic primary cells through their temporal response to shear stress.

Cancer cell transformation is often accompanied by a modification of their viscoelastic properties. When capturing the stress-to-strain response of primary chronic myelogenous leukemia (CML) cells, from two data sets of CD34+ hematopoietic cells isolated from healthy and leukemic bone marrows, we show that the mean shear relaxation modulus increases upon cancer transformation. This stiffening of the cells comes along with local rupture events, detected as reinforced sharp local maxima of this modulus, suggesting that these cancer cells respond to a local mechanical stress by a cascade of local brittle failure events.

A matched case-control study of toxoplasmosis after allogeneic haematopoietic stem cell transplantation: still a devastating complication.

Toxoplasmosis (TXP) is a life-threatening complication of allogeneic haematopoietic stem cell transplantation (AHSCT). Little is known about the risk factors and there is no consensus on prophylactic measures. To investigate the risk factors, we conducted a single-centre, retrospective matched case-control study among adults who underwent AHSCT from January 2006 to March 2015 in our hospital. TXP cases were identified from the prospectively maintained hospital's database. The 1:2 control population consisted of the two patients who received an AHSCT immediately before and after each case with similar donor relationship (related, unrelated) but who did not develop TXP. Risk factors were identified by conditional logistic regression. Clinical features and outcome of TXP were examined. Twenty-three (3.9%) cases of TXP (20 diseases, three infections) were identified among 588 AHSCT recipients. Twenty (87%) cases had a positive pre-transplant Toxoplasma gondii serology. In comparison with 46 matched control patients, risk factors were the absence of effective anti-Toxoplasma prophylaxis (odds ratio (OR) 11.95; 95% CI 3.04-46.88; p <0.001), high-grade (III-IV) acute graft-versus-host-disease (OR 3.1; 95% CI 1.04-9.23; p 0.042) and receipt of the tumour necrosis factor-α blocker etanercept (OR 12.02; 95% CI 1.33-108.6; p 0.027). Mortality attributable to TXP was 43.5% (n = 10). Non-relapse mortality rates during the study period of cases and controls were 69.6% (n = 16) and 17.4% (n = 8), respectively. Lung involvement was the dominant clinical feature (n = 14). Two cases were associated with graft failure, one preceded by haemophagocytic syndrome. Given TXP-related morbidity and attributable mortality, anti-Toxoplasma prophylaxis is essential for optimized management of seropositive AHSCT recipients.

Actinomycosis after allogeneic hematopoietic stem cell transplantation despite penicillin prophylaxis.

Actinomycosis is a rare chronic and multifaceted disease caused by Actinomyces species frequently mimicking malignancy or other chronic granulomatous lung diseases. We report 4 original presentations of actinomycosis arising under supposed penicillin prophylaxis in allogeneic stem cell transplantation recipients.

The BMI1 polycomb protein represses cyclin G2-induced autophagy to support proliferation in chronic myeloid leukemia cells.

The BMI1 polycomb protein regulates self-renewal, proliferation and survival of cancer-initiating cells essentially through epigenetic repression of the CDKN2A tumor suppressor locus. We demonstrate here for the first time that BMI1 also prevents autophagy in chronic myeloid leukemia (CML) cell lines, to support their proliferation and clonogenic activity. Using chromatin immunoprecipitation, we identified CCNG2/cyclin G2 (CCNG2) as a direct BMI1 target. BMI1 downregulation in CD34+ CML cells by PTC-209 pharmacological treatment or shBMI1 transduction triggered CCNG2 expression and decreased clonogenic activity. Also, ectopic expression of CCNG2 in CD34+ CML cells strongly decreased their clonogenicity. CCNG2 was shown to act by disrupting the phosphatase 2A complex, which activates a PKCζ-AMPK-JNK-ERK pathway that engages autophagy. We observed that BMI1 and CCNG2 levels evolved inversely during the progression of CML towards an acute deadly phase, and therefore hypothesized that BMI1 could support acute transformation of CML through the silencing of a CCNG2-mediated tumor-suppressive autophagy response.

Subcutaneous omacetaxine mepesuccinate in patients with chronic myeloid leukemia in tyrosine kinase inhibitor-resistant patients: review and perspectives.

The treatment of chronic myelogenous leukemia (CML) has been revolutionized by the introduction of tyrosine kinase inhibitors (TKI), however, with the exception of ponatinib, none of the existing licensed agents seem to eradicate the reservoir of Philadelphia positive stem cells, thus sustaining the disease over time, and retaining activity in cells and patients harboring an ABL T315I mutation. Omacetaxine mepesuccinate (OMA), formerly known as homoharringtonine, is a cephalotaxus alkaloid derivative and an inhibitor of protein synthesis without tyrosine kinase activity developed 35 years ago by Chinese investigators in the treatment of leukemia. This compound demonstrates specific activity in CML and has been recently commercialized in the U.S. for the treatment of patients in chronic or accelerated phase CML with resistance and/or intolerance to two or more tyrosine kinase inhibitors or harboring a T315I ABL mutation. CML patients with a T315I mutation experienced poor overall survival rates in the pre-ponatinib era (median for CP CML 24 months). Recent studies demonstrate the activity of OMA even in such a poor prognosis population. We hereby detail the development of OMA as an effective agent in CML in these patients.

High burden of BK virus-associated hemorrhagic cystitis in patients undergoing allogeneic hematopoietic stem cell transplantation.

BK virus (BKV) reactivation has been increasingly associated with the occurrence of late-onset hemorrhagic cystitis (HC) after allogeneic hematopoietic SCT (allo-HSCT) resulting in morbidity and sometimes mortality. We investigated the incidence, risk factors and outcome of BKV-HC in 323 consecutive adult patients undergoing allo-HSCT over a 5-year period. BK viremia values for HC staging were evaluated, as well as the medico-economic impact of the complication. Forty-three patients developed BKV-HC. In univariate analysis, young age (P=0.028), unrelated donor (P=0.0178), stem cell source (P=0.0001), HLA mismatching (P=0.0022) and BU in conditioning regimen (P=0.01) were associated with a higher risk of developing BKV-HC. In multivariate analysis, patients receiving cord blood units (CBUs) (P=0.0005) and peripheral blood stem cells (P=0.011) represented high-risk subgroups for developing BKV-HC. BK viremia was directly correlated to HC severity (P=0.011) with a 3 to 6-log peak being likely associated with grades 3 or 4 HC. No correlation was found between BKV-HC and acute graft versus host disease or mortality rate. Patients with BKV-HC required a significantly longer duration of hospitalization (P<0.0001), more RBC (P=0.0003) and platelet transfusions (P<0.0001). Over the 5-year study period, the financial cost of the complication was evaluated at \[euro]2 376 076 ($3 088 899). Strategies to prevent the occurrence of late-onset BKV-HC after allo-HSCT are urgently needed, especially in CBU and peripheral blood stem cell recipients. BK viremia correlates with the severity of the disease. Prospective studies are required to test prophylactic approaches.

[History of chronic myeloid leukemia: a paradigm in the treatment of cancer]. / Historique de la leucémie myéloïde chronique : un paradigme de traitement du cancer.

During two centuries, advances in medicine and medical research have helped to understand the pathophysiology of chronic myelogenous leukemia (CML). This hematologic malignancy is a unique model of oncogenesis where a single molecular hit, causing cell proliferation and survival, was identified. The chromosomal abnormality first highlighted by P. Nowell and D. Hungerford in 1960, and characterized as the reciprocal translocation t(9;22)(q34;q11), the Philadelphia chromosome, discovered in leukemic cells, by J. Rowley in 1973. At the end of the 20th century, the contribution of molecular biology techniques was crucial by the discovery of the BCR-ABL1 hybrid oncogene derived from the t(9;22), responsible for the translation of an aberrant protein tyrosine kinase. This BCR-ABL1 kinase deregulates signaling pathways that control normal cell cycle and survival in primitive hematopoietic cells and is thus responsible for malignant cell accumulation observed in CML. It was then only necessary to develop a targeted treatment adapted to this molecular hit. Recently, tyrosine kinase inhibitors, by their specific inhibitory activity of BCR-ABL, have revolutionized the treatment of CML, allowing rates of haematological, cytogenetic and molecular responses never seen to date, and has significantly improved the overall survival and the quality of life of patients.

A successful renal transplantation for renal failure after dasatinib-induced thrombotic thrombocytopenic purpura in a patient with imatinib-resistant chronic myelogenous leukaemia on nilotinib.

Second-generation tyrosine kinase inhibitors (TKI2) often induce molecular remission, and prolonged survival with a better tolerance in imatinib-resistant chronic myelogenous leukaemia (CML) patients. We report the case of a CML in first chronic phase who was diagnosed in August 2003 in a young 24 year-old Caucasian woman. Our patient received first imatinib and then dasatinib and nilotinib. Imatinib was well tolerated and she developed TTP/HUS on dasatinib without documented evolution of CML and finally obtained MR5.0 with nilotinib and without any side effect. This case also illustrates the absence of cross-resistance and side-effects between the different TKIs and the feasibility of kidney transplantation associated with a nilotinib treatment of CML allowing a continuing MR5.0 and no further side effects.

A phase 2 trial of ponatinib in Philadelphia chromosome-positive leukemias.

BACKGROUND: Ponatinib is a potent oral tyrosine kinase inhibitor of unmutated and mutated BCR-ABL, including BCR-ABL with the tyrosine kinase inhibitor-refractory threonine-to-isoleucine mutation at position 315 (T315I). We conducted a phase 2 trial of ponatinib in patients with chronic myeloid leukemia (CML) or Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph-positive ALL). METHODS: We enrolled 449 heavily pretreated patients who had CML or Ph-positive ALL with resistance to or unacceptable side effects from dasatinib or nilotinib or who had the BCR-ABL T315I mutation. Ponatinib was administered at an initial dose of 45 mg once daily. The median follow-up was 15 months. RESULTS: Among 267 patients with chronic-phase CML, 56% had a major cytogenetic response (51% of patients with resistance to or unacceptable side effects from dasatinib or nilotinib and 70% of patients with the T315I mutation), 46% had a complete cytogenetic response (40% and 66% in the two subgroups, respectively), and 34% had a major molecular response (27% and 56% in the two subgroups, respectively). Responses were observed regardless of the baseline BCR-ABL kinase domain mutation status and were durable; the estimated rate of a sustained major cytogenetic response of at least 12 months was 91%. No single BCR-ABL mutation conferring resistance to ponatinib was detected. Among 83 patients with accelerated-phase CML, 55% had a major hematologic response and 39% had a major cytogenetic response. Among 62 patients with blast-phase CML, 31% had a major hematologic response and 23% had a major cytogenetic response. Among 32 patients with Ph-positive ALL, 41% had a major hematologic response and 47% had a major cytogenetic response. Common adverse events were thrombocytopenia (in 37% of patients), rash (in 34%), dry skin (in 32%), and abdominal pain (in 22%). Serious arterial thrombotic events were observed in 9% of patients; these events were considered to be treatment-related in 3%. A total of 12% of patients discontinued treatment because of an adverse event. CONCLUSIONS: Ponatinib had significant antileukemic activity across categories of disease stage and mutation status. (Funded by Ariad Pharmaceuticals and others; PACE ClinicalTrials.gov number, NCT01207440 .).

Phase 2 study of subcutaneous omacetaxine mepesuccinate for chronic-phase chronic myeloid leukemia patients resistant to or intolerant of tyrosine kinase inhibitors.

Omacetaxine mepesuccinate (omacetaxine) is a first-in-class cephalotaxine with a unique mode of action, independent of BCR-ABL, that has shown promising activity in patients with chronic myeloid leukemia (CML). This multicenter, noncomparative, open-label phase 2 study evaluated the efficacy and safety of subcutaneous omacetaxine in CML patients with resistance or intolerance to two or more tyrosine kinase inhibitors (TKIs); results in patients in chronic phase are reported here. Patients received subcutaneous omacetaxine 1.25 mg/m² twice daily days 1-14 every 28 days until hematologic response (up to a maximum of six cycles), then days 1-7 every 28 days as maintenance. Primary endpoints were rates of hematologic response lasting >8 weeks and major cytogenetic response (MCyR). Forty-six patients were enrolled: all had received imatinib, 83% had received dasatinib, and 57% nilotinib. A median 4.5 cycles of omacetaxine were administered (range, 1-36). Hematologic response was achieved or maintained in 31 patients (67%); median response duration was 7.0 months. Ten patients (22%) achieved MCyR, including 2 (4%) complete cytogenetic responses. Median progression-free survival was 7.0 months [95% confidence interval (CI), 5.9-8.9 months], and overall survival was 30.1 months (95% CI, 20.3 months-not reached). Grade 3/4 hematologic toxicity included thrombocytopenia (54%), neutropenia (48%), and anemia (33%). Nonhematologic adverse events were predominantly grade 1/2 and included diarrhea (44%), nausea (30%), fatigue (24%), pyrexia (20%), headache (20%), and asthenia (20%). Subcutaneous omacetaxine may offer clinical benefit to patients with chronic-phase CML with resistance or intolerance to multiple TKI therapies.

Peripheral artery occlusive disease in chronic phase chronic myeloid leukemia patients treated with nilotinib or imatinib.

Several retrospective studies have described the clinical manifestation of peripheral artery occlusive disease (PAOD) in patients receiving nilotinib. We thus prospectively screened for PAOD in patients with chronic phase chronic myeloid leukemia (CP CML) being treated with tyrosine kinase inhibitors (TKI), including imatinib and nilotinib. One hundred and fifty-nine consecutive patients were evaluated for clinical and biochemical risk factors for cardiovascular disease. Non-invasive assessment for PAOD included determination of the ankle-brachial index (ABI) and duplex ultrasonography. A second cohort consisted of patients with clinically manifest PAOD recruited from additional collaborating centers. Pathological ABI were significantly more frequent in patients on first-line nilotinib (7 of 27; 26%) and in patients on second-line nilotinib (10 of 28; 35.7%) as compared with patients on first-line imatinib (3 of 48; 6.3%). Clinically manifest PAOD was identified in five patients, all with current or previous nilotinib exposure only. Relative risk for PAOD determined by a pathological ABI in first-line nilotinib-treated patients as compared with first-line imatinib-treated patients was 10.3. PAOD is more frequently observed in patients receiving nilotinib as compared with imatinib. Owing to the severe nature of clinically manifest PAOD, longitudinal non-invasive monitoring and careful assessment of risk factors is warranted.

Myeloma cells inhibit non-canonical wnt co-receptor ror2 expression in human bone marrow osteoprogenitor cells: effect of wnt5a/ror2 pathway activation on the osteogenic differentiation impairment induced by myeloma cells.

Multiple myeloma (MM) is characterized by the impaired osteogenic differentiation of human mesenchymal stromal cells (hMSCs). Canonical Wnt signaling is critical for the regulation of bone formation, however, recent evidence suggests that the non-canonical Wnt agonist Wnt5a stimulates human osteoblastogenesis through its co-receptor Ror2. The effects of MM cells on non-canonical Wnt signaling and the effect of the activation of this pathway on MM-induced osteoblast exhaustion are not known and were investigated in this study. We found that the osteogenic differentiation of bone marrow hMSCs toward osteoprogenitor cells (PreOB) significantly increased Ror2 expression, and that MM cells inhibit Ror2 expression by PreOB in co-culture by inhibiting the non-canonical Wnt5a signaling. The activation of the non-canonical Wnt pathway in hMSCs by means of Wnt5a treatment and the overexpression of Wnt5 or Ror2 by lentiviral vectors increased the osteogenic differentiation of hMSCs and blunted the inhibitory effect of MM in co-culture. Consistently, Wnt5a inhibition by specific small interfering RNA reduced the hMSC expression of osteogenic markers. Our findings demonstrate that the Wnt5a/Ror2 pathway is involved in the pathophysiology of MM-induced bone disease and that the activation of the non-canonical Wnt5a/Ror2 pathway in hMSCs increases osteogenic differentiation and may counterbalance the inhibitory effect of MM cells.

First-line imatinib mesylate in patients with newly diagnosed accelerated phase-chronic myeloid leukemia.

Imatinib mesylate is the sole BCR-ABL tyrosine kinase inhibitor approved as first-line treatment of accelerated-phase (AP) chronic myeloid leukemia (CML). Indication was based on the STI571 0109 study, in which imatinib favorably compared to historical treatments in patients failing prior therapies. The relevance of these results to currently newly diagnosed AP-CML patients remains unknown. We evaluated the benefit of imatinib in 42 newly diagnosed AP-CML patients. In all, 16 patients had hematological acceleration without chromosomal abnormalities in addition to the Philadelphia chromosome (ACAs; HEM-AP), 16 solely had ACAs (ACA-AP) and 10 had hematological acceleration plus ACAs (HEM-AP + ACA). Major cytogenetic responses were achieved in 93.7% of HEM-AP patients, 75% of patients with ACA-AP (P=NS) and 40% of patients with HEM-AP + ACA (P=0.0053). The 24-month failure-free survival rate was 87.5% in HEM-AP patients, 43.8% in ACA-AP patients and 15% in HEM-AP + ACA patients (P=0.022). The 24-month estimate of progression-free survival was 100% in HEM-AP patients, 92.8% in ACA-AP patients and 58.3% in HEM-AP + ACA patients (P=0.0052). In conclusion, frontline imatinib allows favorable outcomes in HEM-AP and ACA-AP patients but appears insufficient for patients with HEM-AP + ACA. Broader-target and/or more potent BCR-ABL tyrosine kinase inhibitors alone or in combination may be considered in this setting.