Does IPSS-R down staging before transplantation improve the prognosis of patients with Myelodysplastic neoplasms?

In MDS patients higher IPSS-R at transplant is associated with worse transplant outcome. Thus, it may seem beneficial to improve IPSS-R by therapeutic intervention prior to transplantation in order to "down-stage" the disease risk. However, there is no evidence to date to support this approach. A retrospective analysis of the EBMT transplant registry was performed to investigate the role of therapeutic interventions prior to transplantation with regard to changes in IPSS-R and transplant outcomes. A total of 1482 MDS patients with sufficient data to calculate IPSS-R at diagnosis and at time of transplantation were selected and analysed for transplant outcome in a multivariable Cox model including IPSS-R at diagnosis, treatment intervention, change in IPSS-R before transplant and several patient and transplant variables. Transplant outcome was unaffected by IPSS-R change in untreated patients and moderately superior in chemotherapy-treated patients with improved IPSS-R at transplant. Improved IPSS-R after hypomethylating agents (HMA) or other therapies showed no beneficial effect. However, when IPSS-R progressed after chemotherapy, (HMA) or other therapies, transplant outcome was worse than without any prior treatment. Similar results were found when reduction or increase in bone marrow (BM) blasts between diagnosis and transplantation was considered. The results show a limited benefit of IPSS-R down staging or reduction of BM blasts after chemotherapy and no benefit for HMA or other treatments and thus question the role of prior therapy in MDS patients scheduled for transplantation. The model-based survival estimates should help inform decision making for both doctors and patients.

Sequence not salvage

Chimeric antigen receptor T-cell (CAR-T) therapy for the treatment of multiple myeloma (MM) has fundamentally changed the relapsed and refractory therapeutic landscape, but the disease remains incurable. Two CAR-T products, idecabtagene vicleucel (ide-cel; Abecma) and ciltacabtagene autoleucel (cilta-cel, Carvykti), have been FDA- and EMA-approved for the treatment of relapsed/refractory MM (RRMM); both target B-cell maturation antigen (BCMA), a surface glycoprotein highly expressed on MM cells. Despite deep and durable responses following CAR-T therapy, most patients will need subsequent treatment, and the optimal next-line therapy is presently unclear. Commentary on: Liu et al. Outcomes in patients with multiple myeloma receiving salvage treatment after BCMA-specific CAR-T therapy: A retrospective analysis of LEGEND-2. Br J Haematol 2024;204:1780-1789.

Mismatched related donor allogeneic haematopoietic cell transplantation compared to other donor types for Ph+ chronic myeloid leukaemia: A retrospective analysis from the Chronic Malignancies Working Party of the EBMT

Allogeneic haematopoietic cell transplantation (allo-HCT) remains an option for tyrosine kinase inhibitor-resistant chronic myeloid leukaemia (CML) in first chronic phase (CP1) and high-risk patients with advanced disease phases. In this European Society for Blood and Marrow Transplantation (EBMT) registry-based study of 1686 CML patients undergoing first allo-HCT between 2012 and 2019, outcomes were evaluated according to donor type, particularly focusing on mismatched related donors (MMRDs). Median age at allo-HCT was 46 years (IQR 36-55). Disease status was CP1 in 43%, second CP (CP2) or later in 27%, accelerated phase in 12% and blast crisis in 18%. Donor type was matched related (MRD) in 39.2%, MMRD in 8.1%, matched unrelated (MUD) in 40.2%, and mismatched unrelated (MMUD) in 12.6%. In 4 years, overall survival (OS) for MRD, MMRD, MUD and MMUD was 61%, 56%, 63% and 59% (p = 0.21); relapse-free survival (RFS) was 48%, 42%, 52% and 46% (p = 0.03); cumulative incidence of relapse (CIR) was 33%, 37%, 27% and 30% (p = 0.07); non-relapse mortality (NRM) was 19%, 21%, 21% and 24% (p = 0.21); and graft-versus-host disease (GvHD)-free/relapse-free survival (GRFS) was 16%, 18%, 22% and 15% (p = 0.05) respectively. On multivariate analysis, MMRD use associated with longer engraftment times and higher risk of graft failure compared to MRD or MUD. There was no statistical evidence that MMRD use associated with different OS, RFS and incidence of GvHD compared to other donor types.

In the era of Bortezomib-based Induction, intensification of Melphalan-based conditioning with Bortezomib does not improve Survival Outcomes in newly diagnosed Multiple Myeloma: a study from the Chronic Malignancies Working Party of the EBMT

Bortezomib (Vel)- Melphalan 200 mg/m2 (Mel200) (Vel-Mel) has been utilised to intensify conditioning in autologous hematopoietic stem cell transplantation (AHCT) for multiple myeloma (MM). This EBMT registry-based study compared Vel-Mel with Mel200 during upfront AHCT. Between 2010 and 2017, MM patients who received Vel-Mel (n = 292) conditioning were compared with 4,096 Mel200 patients in the same 58 centres. Pre-AHCT, compared to Mel200 patients, Vel-Mel patients had similar International Staging System (ISS) scores and cytogenetic risk profiles; a similar proportion had received bortezomib-based induction (85% and 87.3%, respectively) though they were younger with a better performance status. Vel-Mel patients were more likely to achieve CR post-induction (40.6% vs 20.3%, p < 0.001) and by day 100 of AHCT (CR/VGPR: 70.2 % vs. 57.2%, p < 0.001). There was no difference in 3-year PFS (49% vs 46%, p = 0.06) or early post-AHCT mortality. In multivariable analysis, Vel-Mel associated with inferior PFS (HR: 1.69 (1.27-2.25, p < 0.001) and OS (HR:1.46 (1.14-1.86,p = 0.002), similar to negative effects on PFS of advanced ISS (HR:1.56 (1.33-1.83, p < 0.001), high-risk cytogenetics (HR:1.43(1.18-1.74, p < 0.001) and poor post-induction response(<=PR)(HR: 1.43(1.25-1.62, p < 0.001) Overall, despite superior pre- and post-AHCT responses, there was no improvement in PFS or OS following Vel-Mel. This data supports the findings of the smaller prospective IFM study.

Graft-versus-Host Disease Prophylaxis with Post- Transplantation Cyclophosphamide in Chronic Myeloid Leukemia Patients Undergoing Allogeneic Hematopoietic Cell Transplantation from an Unrelated or Mismatched Related Donor: A Comparative Study from the Chronic Malignancies Working Party of the EBMT (CMWP-EBMT)

Outcomes following allogeneic hematopoietic cell transplantation (allo-HCT) for chronic myeloid leukemia (CML) with post-transplantation cyclophosphamide (PTCy) using an unrelated donor (UD) or a mismatched related donor (MMRD) remain unknown. We report a retrospective comparison of PTCy-based allo-HCT from a UD, non-PTCy allo-HCT from a UD, and PTCy allo-HCT from an MMRD. Inclusion criteria were adult patients with CML undergoing first allo-HCT between 2012 and 2019 from a UD with either PTCy or non-PTCy graft-versus-host disease (GVHD) prophylaxis or from an MMRD using PTCy. The primary endpoint was GVHD-free/relapse-free survival (GRFS). A total of 1341 patients were included (82% in the non-PTCy UD cohort). With a median follow-up of 34.9 months, the 3-year GRFS was 43% in the non-PTCy cohort, 37% in the PTCy-UD cohort, and 39% PTCy-MMRD cohort (P = .15). Multivariable analyses revealed no significant differences among the 3 cohorts in terms of overall survival (OS), progression-free survival, RI, and nonrelapse mortality. Factors independently associated with worse OS in the overall cohort were Karnofsky Performance Status <90 (hazard ratio [HR], 1.86; 95% confidence interval [CI], 1.41 to 2.45; P < .001), older age (HR, 1.24, 95% CI, 1.11 to 1.38; P < .001), and disease stage (compared to chronic phase [CP] 1): blast phase (HR, 2.25; 95% CI, 1.60 to 3.16; P < .001), accelerated phase (HR, 1.63; 95% CI, 1.05 to 2.54; P = .03), and CP >2 (HR, 1.58; 95% CI, 1.15 to 2.17; P = .005). These results suggest that allo-HCT in patients with CML using either a UD or an MMRD with PTCy-based GVHD prophylaxis are feasible transplantation, platforms and that the disease stage at allo-HCT remains a major prognostic factor, highlighting the importance of closely monitoring CML patients and proposing transplantation when indicated when still in CP1.

Carfilzomib, lenalidomide and dexamethasone followed by a second ASCT is an effective strategy in first relapse multiple myeloma: a study on behalf of the Chronic malignancies working party of the EBMT

In the setting of a first relapse of multiple myeloma (MM), a second autologous stem cell transplant (ASCT) following carfilzomib-lenalidomide-dexamethasone (KRd) is an option, although there is scarce data concerning this approach. We performed a retrospective study involving 22 EBMT-affiliated centers. Eligible MM patients had received a second-line treatment with KRd induction followed by a second ASCT between 2016 and 2018. Primary objective was to estimate progression-free survival (PFS) and overall survival (OS). Secondary objectives were to assess the response rate and identify significant variables affecting PFS and OS. Fifty-one patients were identified, with a median age of 62 years. Median PFS after ASCT was 29.5 months while 24- and 36-months OS rates were 92.1% and 84.5%, respectively. Variables affecting PFS were an interval over four years between transplants and the achievement of a very good partial response (VGPR) or better before the relapse ASCT. Our study suggests that a relapse treatment with ASCT after KRd induction is an effective strategy for patients with a lenalidomide-sensitive first relapse. Patients with at least four years of remission after a frontline ASCT and who achieved at least a VGPR after KRd induction appear to benefit the most from this approach.

An early post-transplant relapse prediction score in multiple myeloma: a large cohort study from the chronic malignancies working party of EBMT

Early relapse (ER) following Autologous Hematopoietic Cell Transplantation (AHCT) confers a poor prognosis. We therefore developed a novel scoring system to predict ER. A total of 14,367 AHCT-1 patients were transplanted between 2014 and 2019, and were conditioned with Melphalan 200 mg/m2 (Mel200) (n = 7228; 2014-2017) (training cohort); Mel200 (n = 5616; 2018-2019) or Mel140 (n = 1523; 2018-2019) (validation cohorts). PFS-12 and the Cumulative Incidence of Relapse at 12 months were 84.1% and 14.7% (training Mel200), 87.2% and 11.6% (validation Mel200), and 80.3% and 16.9% (validation Mel140), respectively. The points in the risk score were: 0, 1,2 for ISS stages I, II, and III; Disease status: 0 (CR/VGPR); 1 (PR); 2 (SD/MR); 4 (Relapse/Progression); and 1 for Karnofsky ≤ 70. The distribution of scores: 0 (24%), 1 (33.9%), 2 (29.6 %), 3 (9.5%), and ≥4 (2.7%). The score separated PFS-12, with the lowest risk group (n = 1752) having a PFS-12 of 91.7% and the highest risk group (n = 195) 57.1%. This also applied in cytogenetically high-risk patients. If the pre-score baseline risks are 15% (standard risk) and 25% (high-risk), a score of ≥4 confers calculated risks of 38% and 54%, respectively. This novel EBMT ER score, therefore, allows for the identification of five discrete prognostic groups.

Impact of newly diagnosed extramedullary myeloma on outcome after first autograft followed by maintenance: A CMWP-EBMT study

BACKGROUND

No adequate data exist on the impact of multiple myeloma (MM) with extramedullary disease (EMD) after autograft and maintenance therapy.

METHODS

We identified 808 patients with newly diagnosed MM who received first autograft, of whom 107 had EMD (83 paraskeletal and 24 organ involvement), and who had been reported to the EBMT registry December 2018. Distribution according to type of involvement was similar between the treatment groups (p = .69). For EMD, 46 (40%) received thalidomide, 59 (51%) lenalidomide, and 11 (10%) bortezomib.

RESULTS

The median follow-up from maintenance start was 44 months. Three-year progression-free survival (PFS) was 52% (48%-57%) for no EMD, 56% (44%-69%) for paraskeletal involvement, and 45% (22%-68%) for organ involvement (p = .146). Early PFS (within first year) appeared to be significantly worse for organ involvement (hazard ratio, 3.40), while no significant influence was found after first year from maintenance start. Three-year overall survival (OS) was 81% (77%-84%), 88% (80%-96%), and 68% (47%-89%; p = .064), respectively. With thalidomide as reference, lenalidomide was significantly associated with better PFS and OS, whereas bortezomib appeared to improve outcome specifically in EMD.

CONCLUSION

Lenalidomide maintenance is standard of care for MM without EMD, whereas extramedullary organ involvement remains a significant risk factor for worse outcome, especially for early events after maintenance start.

The European landscape on allogeneic haematopoeietic cell transplantation in Chronic Lymphocytic Leukaemia between 2009 and 2019: a perspective from the Chronic Malignancies Working Party of the EBMT

Allogeneic transplantation (allo-HCT) is a curative treatment in CLL whose efficacy including the most severe forms had led to the 2006 EBMT recommendations. The advent after 2014 of targeted therapies has revolutionized CLL management, allowing prolonged control to patients who have failed immunochemotherapy and/or have TP53 alterations. We analysed the pre COVID pandemic 2009-2019 EBMT registry. The yearly number of allo-HCT raised to 458 in 2011 yet dropped from 2013 onwards to an apparent plateau above 100. Within the 10 countries who were under the EMA for drug approval and performed 83.5% of those procedures, large initial differences were found but the annual number converged to 2-3 per 10 million inhabitants during the 3 most recent years suggesting that allo-HCT remains applied in selected patients. Long-term follow-up on targeted therapies shows that most patients relapse, some early, with risk factors and resistance mechanisms being described. The treatment of patients exposed to both BCL2 and BTK inhibitors and especially those with double refractory disease will become a challenge in which allo-HCT remains a solid option in competition with emerging therapies that have yet to demonstrate their long-term effectiveness.

Allogeneic hematopoietic cell transplantation in patients with chronic phase chronic myeloid leukemia in the era of third generation tyrosine kinase inhibitors: A retrospective study by the chronic malignancies working party of the EBMT

Following the introduction of tyrosine kinase inhibitors (TKI), the number of patients undergoing allogeneic hematopoietic cell transplantation (allo-HCT) for chronic phase (CP) chronic myeloid leukemia (CML) has dramatically decreased. Imatinib was the first TKI introduced to the clinical arena, predominantly utilized in the first line setting. In cases of insufficient response, resistance, or intolerance, CML patients can subsequently be treated with either a second or third generation TKI. Between 2006 and 2016, we analyzed the impact of the use of 1, 2, or 3 TKI prior to allo-HCT for CP CML in 904 patients. A total of 323-, 371-, and 210 patients had 1, 2, or 3 TKI prior to transplant, respectively; imatinib (n = 778), dasatinib (n = 508), nilotinib (n = 353), bosutinib (n = 12), and ponatinib (n = 44). The majority had imatinib as first TKI (n = 747, 96%). Transplants were performed in CP1, n = 549, CP2, n = 306, and CP3, n = 49. With a median follow-up of 52 months, 5-year OS for the entire population was 64.4% (95% CI 60.9-67.9%), PFS 50% (95% CI 46.3-53.7%), RI 28.7% (95% CI 25.4-32.0%), and NRM 21.3% (95% CI 18.3-24.2%). No difference in OS, PFS, RI, or NRM was evident related to the number of TKI prior to allo-HCT or to the type of TKI (p = ns). Significant factors influencing OS and PFS were > CP1 versus CP1 and Karnofsky performance (KPS) score > 80 versus ≤80, highlighting CP1 patients undergoing allo-HCT have improved survival compared to >CP1 and the importance of careful allo-HCT candidate selection.

Allogeneic hematopoietic cell transplant for hairy cell leukemia: EBMT experience

Not available.

Phase 2 studies of lenalidomide, subcutaneous bortezomib, and dexamethasone as induction therapy in patients with newly diagnosed multiple myeloma

There are limited prospective data on lenalidomide, subcutaneous bortezomib, and dexamethasone (RsqVd) in transplant-eligible/transplant-ineligible patients with newly diagnosed multiple myeloma. Reliable biomarkers for efficacy and toxicity are required to better tailor therapy. Two parallel studies were conducted by Cancer Trials Ireland (CTI; NCT02219178) and the Dana-Farber Cancer Institute (DFCI; NCT02441686). Patients received four 21-day cycles of RsqVd and could then receive either another 4 cycles of RsqVd or undergo autologous stem cell transplant. Postinduction/posttransplant, patients received lenalidomide maintenance, with bortezomib included for high-risk patients. The primary endpoint was overall response rate (ORR) after 4 cycles of RsqVd. Eighty-eight patients were enrolled and 84 treated across the two studies; median age was 64.7 (CTI study) and 60.0 years (DFCI study), and 59% and 57% had stage II-III disease. Pooled ORR after 4 cycles in evaluable patients was 93.5%, including 48.1% complete or very good partial responses (CTI study: 91.9%, 59.5%; DFCI study: 95.0%, 37.5%), and in the all-treated population was 85.7% (44.0%). Patients received a median of 4 (CTI study) and 8 (DFCI study) RsqVd cycles; 60% and 31% of patients (CTI study) and 33% and 51% of patients (DFCI study) underwent transplant or received further RsqVd induction, respectively. The most common toxicity was peripheral neuropathy (pooled: 68%, 7% grade 3-4; CTI study: 57%, 7%; DFCI study: 79%, 7%). Proteomics analyses indicated elevated kallikrein-6 in good versus poor responders, decreased midkine in good responders, and elevated macrophage inflammatory protein 1-alpha in patients who stopped treatment from neurotoxicity, suggesting predictive biomarkers warranting further investigation.

Management of adults and children receiving CAR T-cell therapy: 2021 best practice recommendations of the European Society for Blood and Marrow Transplantation (EBMT) and the Joint Accreditation Committee of ISCT and EBMT (JACIE) and the European Haematology Association (EHA)

BACKGROUND

Several commercial and academic autologous chimeric antigen receptor T-cell (CAR-T) products targeting CD19 have been approved in Europe for relapsed/refractory B-cell acute lymphoblastic leukemia, high-grade B-cell lymphoma and mantle cell lymphoma. Products for other diseases such as multiple myeloma and follicular lymphoma are likely to be approved by the European Medicines Agency in the near future.

DESIGN

The European Society for Blood and Marrow Transplantation (EBMT)-Joint Accreditation Committee of ISCT and EBMT (JACIE) and the European Haematology Association collaborated to draft best practice recommendations based on the current literature to support health care professionals in delivering consistent, high-quality care in this rapidly moving field.

RESULTS

Thirty-six CAR-T experts (medical, nursing, pharmacy/laboratory) assembled to draft recommendations to cover all aspects of CAR-T patient care and supply chain management, from patient selection to long-term follow-up, post-authorisation safety surveillance and regulatory issues.

CONCLUSIONS

We provide practical, clinically relevant recommendations on the use of these high-cost, logistically complex therapies for haematologists/oncologists, nurses and other stakeholders including pharmacists and health sector administrators involved in the delivery of CAR-T in the clinic.

Autologous hematopoietic cell transplantation for relapsed multiple myeloma performed with cells procured after previous transplantation-study on behalf of CMWP of the EBMT

Autologous hematopoietic cell transplantation (auto-HCT) may be performed in multiple myeloma (MM) patients relapsing after a previous auto-HCT. For those without an adequate dose of stored stem cells, remobilization is necessary. This retrospective study included patients who, following disease relapse after the first auto-HCT(s), underwent stem cell remobilization and auto-HCT performed using these cells. There were 305 patients, 68% male, median age at salvage auto-HCT was 59 years. The median time to relapse after the first-line penultimate auto-HCT(s) was 30.6 months, the median follow-up after salvage auto-HCT 31 months. The 2- and 4-year non-relapse mortality (NRM) after the salvage auto-HCT was 5 and 9%, the relapse incidence 56 and 76%, respectively. Overall survival (OS) after 2 and 4 years was 76 and 52%, progression-free survival (PFS) 39 and 15%. In multivariable analysis an increasing interval between the penultimate auto-HCT and relapse was associated with better OS and PFS, later calendar year of salvage auto-HCT with better OS. In conclusion, salvage auto-HCT performed with cells remobilized after a previous auto-HCT was associated with acceptable NRM. The leading cause of failure was disease progression of MM, which correlated with a shorter interval from the penultimate auto-HCT to the first relapse.

Trends in autologous stem cell transplantation for newly diagnosed multiple myeloma: Changing demographics and outcomes in European Society for Blood and Marrow Transplantation centres from 1995 to 2019

Multiple myeloma (MM) accounts for 10% of haematological malignancies. Overall survival (OS) has improved in recent years due to increased use of autologous stem cell transplantation (ASCT) in the treatment of newly diagnosed MM and the advent of novel agents, including proteasome inhibitors, immunomodulatory drugs and monoclonal antibodies. To assess trends in ASCT including patient selection, choice of induction regimen, depth of response and survival, we performed a retrospective analysis of all patients undergoing first ASCT for MM in European Society for Blood and Marrow Transplantation centres between 1995 and 2019. A total of 117 711 patients across 575 centres were included. The number of transplants performed increased sevenfold across the study period. The median age increased from 55 to 61 years, and the percentage of patients aged >65 years rose from 7% to 30%. Use of chemotherapy-based induction fell significantly, being largely replaced by bortezomib-based regimens. The two-year complete response rate increased from 22% to 42%. The five-year progression-free survival and OS rates increased from 28% to 31% and from 52% to 69%, respectively. Transplant mortality fell from 5.9% to 1.5%. Ongoing advances in MM treatment may challenge the future role of ASCT. However, at the current time, ASCT remains central to the MM treatment paradigm.

A novel aryl-guanidinium derivative, VP79s, targets the signal transducer and activator of transcription 3 signaling pathway, downregulates myeloid cell leukaemia-1 and exhibits preclinical activity against multiple myeloma

AIMS

We have recently described a novel guanidinium-based compound, VP79s, which induces cytotoxicity in various cancer cell lines. Here, we aim to investigate the activity of VP79s and associated mechanisms of action in multiple myeloma (MM) cells in vitro and ex vivo.

MAIN METHODS

The effects of VP79s on cell viability and induction of apoptosis was examined in a panel of drug-sensitive and drug-resistant MM cell lines, as well as ex vivo patient samples and normal donor lymphocytes and platelets. Cell signaling pathways associated with the biological effects of VP79s were analysed by immunoblotting and flow cytometry. Gene expression changes were assessed by quantitative real-time PCR analysis.

KEY FINDINGS

VP79s was found to rapidly inhibit both constitutively active and IL-6-induced STAT3 signaling with concurrent downregulation of the IL-6 receptors, CD130 and CD126. VP79s induced a rapid and dose-dependent downregulation of anti-apoptotic Bcl-2 family member, myeloid cell leukaemia-1 (MCL-1). VP79s enhanced bortezomib induced cell death and was also found to overcome bone marrow stromal cell induced drug resistance. VP79s exhibited activity in ex vivo patient samples at concentrations which had no effect on peripheral blood mononuclear cells, lymphocytes and platelets isolated from healthy donors.

SIGNIFICANCE

As VP79s resulted in rapid inhibition of the key IL-6/STAT3 signaling pathway and downregulation of MCL-1 expression with subsequent selective anti-myeloma activity, VP79s may be a potential therapeutic agent with a novel mechanism of action in MM cells.

Post-Transplantation Cyclophosphamide for Graft-versus- Host Disease Prophylaxis in Multiple Myeloma Patients Who Underwent Allogeneic Hematopoietic Cell Transplantation: First Comparison by Donor Type. A Study from the Chronic Malignancies Working Party of the European Society for Blood and Marrow Transplantation

Graft-versus-host disease (GVHD) remains among the major causes of treatment failure in patients with multiple myeloma (MM) undergoing allogeneic hematopoietic cell transplantation (allo-HCT). The use of post-transplantation cyclophosphamide (PT-Cy) is now a well-established and widely used method for GVHD prophylaxis after HLA haploidentical HCT. However, the rationale for using PT-Cy in the setting of matched donor transplantation is less apparent, given the lesser degree of bidirectional alloreactivity. In this retrospective study, we investigated the role of PT-Cy as GVHD prophylaxis in patients with multiple myeloma underoing allo-HCT, among different donor types, to determine cumulative incidence of acute and chronic GVHD and impact on engraftment, progression-free survival (PFS), GVHD-free/relapse- free survival (GRFS), overall survival (OS), and NRM A total of 295 patients with MM underwent allo-HCT using grafts from a matched related donor (MRD; n = 67), matched unrelated donor (MUD; n = 72), mismatched related or unrelated donor (MMRD/MMUD, 1 antigen; n = 27), or haploidentical donor (haplo; n = 129) using PT-Cy between 2012 and 2018. In addition to PT-Cy, agents used in GVHD prophylaxis included calcineurin inhibitors in 239 patients (81%), with mycophenolate mofetil in 184 of those 239 (77%). For grade II-IV acute GVHD, the cumulative incidence at day +100 was 30% (95% confidence interval [CI], 25% to 36%), 9% (95% CI, 5% to 12%) for grade III-IV acute GVHD, and 27% (95% CI, 21% to 32%) for chronic GVHD (limited, 21%; extensive, 6%), with no differences by donor type. The median time to neutrophil engraftment was 19d (95% CI, 18-19), with no significant difference by donor type. The median time to platelet engraftment was delayed in haploidentical donor graft recipients (27 days versus 21 days; P < .001). Two-year OS, PFS, GRFS, and NRM were 51% (95% CI, 45% to 58%), 26% (95% CI, 20% to 32%), 24% (95% CI, 18% to 30%), and 19% (95% CI, 14% to 24%), respectively, with no significant difference between different donor types. In multivariable analyses, compared with the haplo donors, the use of MRDs was associated with significantly better OS (hazard ratio [HR], 0.6; 95% CI, 0.38 to 0.95; P = .029), and the use of MUDs was associated with a significantly higher GRFS (HR, 0.63; 95% CI, 0.42 to 0.97; P = .034). There was a trend toward improved PFS with use of MUDs (HR, 0.69; 95% CI, 0.46 to 1.04; P = .08). Our data show that PT-Cy in MM patients undergoing allo-HCT resulted in low rates of acute and chronic GVHD and led to favorable survival, especially in the matched related donor setting. © 2021 American Society for Transplantation and Cellular Therapy. Published by Elsevier Inc.

Outcomes following second allogeneic haematopoietic cell transplantation in patients with myelofibrosis: a retrospective study of the Chronic Malignancies Working Party of EBMT

Therapeutic management of patients with primary or secondary myelofibrosis (MF) who experience relapse or graft failure following allogeneic haematopoietic cell transplantation (allo-HCT) remains heterogeneous. We retrospectively analyzed 216 patients undergoing a second allo-HCT for either relapse (56%) or graft failure (31%) between 2010 and 2017. Median age was 57.3 years (range 51-63). The same donor as for the first allo-HCT was chosen in 66 patients (31%) of whom 19 received an HLA-identical sibling donor, whereas a different donor was chosen for 116 patients (54%). Median follow-up was 40 months. Three-year overall survival (OS) and relapse-free survival (RFS) were 42% and 39%, respectively. Three-year non-relapse mortality (NRM) and relapse rates were 36% and 25%, respectively. Grade II-IV and III-IV acute GVHD occurred in 25% and 11% of patients, respectively, and the 3-year incidence of chronic GVHD was 33% including 14% for extensive grade. Graft-failure incidence at 1 year was 14%. In conclusion, our data suggest that a second allo-HCT is a potential option for patients failing first allo-HCT for MF albeit careful patient assessment is fundamental to identify individual patients who could benefit from this approach.

Prognostic impact of early-versus-late responses to different induction regimens in patients with myeloma undergoing autologous hematopoietic cell transplantation: Results from the CALM study by the CMWP of the EBMT

BACKGROUND

In autologous stem cell transplant (ASCT)-eligible myeloma patients, prolonged induction does not necessarily improve the depth of response.

METHOD

We analyzed 1222 ASCT patients who were classified based on (a) the interval between induction and stem cell collection, (b) the type of induction regimen: BID (Bortezomib, IMiDs, and Dexamethasone), Bortezomib-based, or CTD (Cyclophosphamide, Thalidomide, and Dexamethasone), and (c) the time to best response (Early ie, best response within 4 or 5 months, depending on the regimen vs Late; Good ie, VGPR or better vs Poor).

RESULTS

The length of induction treatment required to achieve a Good response did not affect PFS (P = .65) or OS (P = .61) post-ASCT. The three types of regimen resulted in similar outcomes: median PFS 31, 27.7 and 30.8 months (P = .31), and median OS 81.7, 92.7, and 77.4 months, respectively (P = .83). On multivariate analysis, neither the type nor the duration of the induction regimen affected OS and PFS, except for Early Good Responders who had a better PFS compared to Early Poor Responders (HR = 1.21, P-value = .02). However, achieving a Good response at induction was associated with a better response (≥VGPR) post-transplant.

CONCLUSION

The kinetics of response did not affect outcomes.

Special review series on 3D organotypic culture models: Introduction and historical perspective

Three dimensional (3D) organ-like (organotypic) culture models are a rapidly advancing area of in vitro biological science. In contrast to monolayer cell culture methods which were developed to achieve proliferation of animal cells in the beginning of in vitro biology, the advancements in 3D culture methods are designed to promote cellular differentiation, and to achieve in vivo–like 3D structure and organotypic functions. This project was conceived through the Society for In Vitro Biology to draw on the expertise of individual scientists with special expertise in organotypic cultures of selected tissues or associated interrogation methods to prepare individual-focused reviews in this series. This introductory manuscript will review the early achievements of animal cell culture in monolayer culture and the limitations of that approach to reproduce functioning organ systems. Among these are the nature and 3D architecture of the substrate on which or in which the cells are grown, physical and mechanical clues from the substrate, cell-cell interactions, and defined biochemical factors that trigger the induction of the 3D organotypic differentiation. The organoid culture requires a source of cells with proliferative capacity (ranging from tissue-derived stem or immortalized cells to the iPSC cultures), a suitable substrate or matrix with the mechanical and stimulatory properties appropriate for the organotypic construct and the necessary stimulation of the culture to drive differentiation of the cell population to form the functioning organotypic construct. Details for each type of organotypic construct will be provided in the following papers.

Are Autologous Stem Cell Transplants Still Required to Treat Myeloma in the Era of Novel Therapies? A Review from the Chronic Malignancies Working Party of the EBMT

Melphalan at a myeloablative dose followed by autologous stem cell transplantation (ASCT) remains the standard of care for transplant-eligible patients with myeloma. However, therapies such as new immunomodulatory drugs and proteasome inhibitors and, more recently, monoclonal antibodies and chimeric antigen receptor T cells are challenging the traditional role of ASCT. Which patients benefit from ASCT? Can its use be delayed until first relapse? The field is moving rapidly as novel agents lead to new patient care strategies. The place of ASCT in this changing landscape will be reviewed and reassessed.

Management of adults and children undergoing chimeric antigen receptor T-cell therapy: best practice recommendations of the European Society for Blood and Marrow Transplantation (EBMT) and the Joint Accreditation Committee of ISCT and EBMT (JACIE)

Chimeric antigen receptor (CAR) T cells are a novel class of anti-cancer therapy in which autologous or allogeneic T cells are engineered to express a CAR targeting a membrane antigen. In Europe, tisagenlecleucel (Kymriah™) is approved for the treatment of refractory/relapsed acute lymphoblastic leukemia in children and young adults as well as relapsed/refractory diffuse large B-cell lymphoma, while axicabtagene ciloleucel (Yescarta™) is approved for the treatment of relapsed/refractory high-grade B-cell lymphoma and primary mediastinal B-cell lymphoma. Both agents are genetically engineered autologous T cells targeting CD19. These practical recommendations, prepared under the auspices of the European Society of Blood and Marrow Transplantation, relate to patient care and supply chain management under the following headings: patient eligibility, screening laboratory tests and imaging and work-up prior to leukapheresis, how to perform leukapheresis, bridging therapy, lymphodepleting conditioning, product receipt and thawing, infusion of CAR T cells, short-term complications including cytokine release syndrome and immune effector cell-associated neurotoxicity syndrome, antibiotic prophylaxis, medium-term complications including cytopenias and B-cell aplasia, nursing and psychological support for patients, long-term follow-up, post-authorization safety surveillance, and regulatory issues. These recommendations are not prescriptive and are intended as guidance in the use of this novel therapeutic class.

Conditioning-based outcomes after allogeneic transplantation for myeloma following a prior autologous transplant (1991-2012) on behalf of EBMT CMWP

OBJECTIVES

The aim of this study was to compare the effect of the intensity of conditioning approaches used in allogeneic transplantation in myeloma-reduced intensity conditioning (RIC), non-myeloablative (NMA), myeloablative conditioning (MAC) or Auto-AlloHCT-on outcomes in patients who had had a prior autologous transplant.

METHODS

A retrospective analysis of the EBMT database (1991-2012) was performed.

RESULTS

A total of 344 patients aged between 40 and 60 years at the time of alloHCT were identified: 169 RIC, 69 NMA, 65 MAC and 41 Auto-Allo transplants. At a median follow-up of 54 months, the probabilities of overall survival (OS) at 5 years were 39% (95% CI 31%-47%), 45% (95% CI 32%-57%), 19% (95% CI 6%-32%) and 34% (95% CI 17%-51%), respectively. Status at allogeneic HCT other than CR or PR conferred a 70% higher risk of death and a 40% higher risk of relapse. OS was markedly lower in the MAC group (P = .004). MAC alloHCT was associated with a higher risk of death than RIC alloHCT until 2002 (HR = 4.1, P < .001) but not after 2002 (HR = 1.2, P = .276).

CONCLUSION

From 1991 to 2002, MAC was associated with poorer OS. Between 2003 and 2012, there were no significant differences in outcomes based on these different approaches.

Sorafenib for relapsed FLT3-ITD-positive acute myeloid leukemia postallogeneic stem cell transplantation presenting as leukemia cutis

Relapse of FLT3-mutated acute myeloid leukemia (AML) following allogeneic stem cell transplantation is associated with poor survival. The clinical utility of sorafenib monotherapy in this setting is described in a patient presenting as leukemia cutis.

An international survey on the management of patients receiving CAR T-cell therapy for haematological malignancies on behalf of the Chronic Malignancies Working Party of EBMT

PURPOSE OF THE STUDY

Two chimeric antigen receptor (CAR) T-cell therapies - Tisagenlecleucel (Kymriah^™) and Axicabtagene ciloleucel (Yescarta^™) - have been approved for commercial use. In order to inform forthcoming EBMT guidelines on the management of adults and children undergoing autologous CAR T-cell therapy, we undertook a survey of experienced clinicians.

METHODS

An online survey with a dual focus on (1) 'real world' patient eligibility criteria and (2) models of care for patient follow-up was sent to experienced physicians.

RESULTS

There were 41 respondents (10 countries) and 93% worked in FACT-JACIE-accredited transplant centres. Most felt that a history of malignancy (57%), prior allo-HCT for B-NHL (78%-81%) and prior treatment with anti-CD19/CD3 BiTE antibodies (76%-86%) do not constitute contra-indications to CAR T therapy. Clinicians were divided as to whether CNS involvement represented an exclusion criterion. There was agreement that patients with viral infections (HIV, Hepatitis B or Hepatitis C) are not eligible. There is no common model of care for long-term follow-up. Most respondents believed that patients should attend the hospital two (43%) to three (33%) times weekly during the first month following discharge. A majority (69%) of respondents work in centres where there is an MDT meeting with a specific focus on follow-up following CAR T Therapy. Follow-up care is currently delivered either in HCT or haematology-oncology outpatient clinics.

CONCLUSION

The responses reveal wide variation in perceived patient eligibility criteria and highlight the need for consensus guidelines. The findings also illustrate the embryonic nature of current follow-up arrangements.

Prevalidation of an Acute Inhalation Toxicity Test Using the EpiAirway In Vitro Human Airway Model

Introduction: Knowledge of acute inhalation toxicity potential is important for establishing safe use of chemicals and consumer products. Inhalation toxicity testing and classification procedures currently accepted within worldwide government regulatory systems rely primarily on tests conducted in animals. The goal of the current work was to develop and prevalidate a nonanimal (in vitro) test for determining acute inhalation toxicity using the EpiAirway™ in vitro human airway model as a potential alternative for currently accepted animal tests.

Materials and Methods: The in vitro test method exposes EpiAirway tissues to test chemicals for 3 hours, followed by measurement of tissue viability as the test endpoint. Fifty-nine chemicals covering a broad range of toxicity classes, chemical structures, and physical properties were evaluated. The in vitro toxicity data were utilized to establish a prediction model to classify the chemicals into categories corresponding to the currently accepted Globally Harmonized System (GHS) and the Environmental Protection Agency (EPA) system.

Results: The EpiAirway prediction model identified in vivo rat-based GHS Acute Inhalation Toxicity Category 1–2 and EPA Acute Inhalation Toxicity Category I–II chemicals with 100% sensitivity and specificity of 43.1% and 50.0%, for GHS and EPA acute inhalation toxicity systems, respectively. The sensitivity and specificity of the EpiAirway prediction model for identifying GHS specific target organ toxicity-single exposure (STOT-SE) Category 1 human toxicants were 75.0% and 56.5%, respectively. Corrosivity and electrophilic and oxidative reactivity appear to be the predominant mechanisms of toxicity for the most highly toxic chemicals.

Conclusions: These results indicate that the EpiAirway test is a promising alternative to the currently accepted animal tests for acute inhalation toxicity.

Management of high-risk Myeloma: an evidence-based review of treatment strategies

INTRODUCTION

Despite the progress made in the treatment of patients with multiple myeloma over recent decades, a significant cohort with high-risk disease as defined by specific clinical and genetic criteria continue to respond poorly to standard treatment. These patients represent a particular challenge to the treating physician and require early identification as well as personalized treatment strategies.

AREAS COVERED

In this review, we discuss the prognostic impact of adverse clinical, radiological and genetic factors, evaluate available scoring systems and highlight key aspects of the therapeutic management of high-risk myeloma. MEDLINE and recent scientific meetings' databases were searched for the keywords 'high-risk' and 'multiple myeloma' and relevant studies relating to both diagnostic and therapeutic approaches were identified. Expert commentary: A case is made for intensive induction using combinations of novel agents, early high-dose therapy supported by autologous stem cell transplantation and the widespread use of maintenance therapies. Novel therapeutic options, especially in the field of immunotherapy, are currently explored in clinical trials and have the potential to further improve outcomes for patients with high-risk multiple myeloma.

Lenalidomide as a novel treatment for refractory acquired von Willebrand syndrome associated with monoclonal gammopathy

Essentials Treatment options are limited for refractory bleeding in acquired von Willebrand Syndrome (AVWS). Lenalidomide therapy was studied in two patients with AVWS due to monoclonal gammopathy (MG). Lenalidomide increased von Willebrand factor (VWF), lowered VWF clearance and resolved bleeding. Lenalidomide is a potential treatment option for refractory bleeding in AVWS secondary to MG.

SUMMARY

Background Acquired von Willebrand syndrome (AVWS) is associated with lymphoproliferative disorders, including monoclonal gammopathy (MG) of undetermined significance (MGUS) and multiple myeloma. Patients commonly present with significant bleeding complications that are difficult to manage, owing to a markedly reduced von Willebrand factor (VWF) half-life. Objectives To investigate the use of the immunomodulatory drug lenalidomide in two patients with severe refractory bleeding caused by AVWS associated with MGs. Results In both patients, lenalidomide treatment resulted in significant clinical improvement, and marked increases in plasma VWF antigen (VWF:Ag) and VWF ristocetin cofactor levels. This normalization in plasma VWF levels was sustained for > 2 years in both patients. Furthermore, in one patient, plasma VWF levels remain normal for at least 14 months following discontinuation of lenalidomide treatment. To investigate the molecular mechanisms underlying these observations, VWF propeptide (VWFpp)/VWF:Ag ratios were analyzed to assess VWF clearance. At enrolment, plasma VWFpp/VWF:Ag ratios were significantly elevated in both patients. Importantly, lenalidomide treatment resulted in normalization of VWFpp/VWF:Ag ratios in both patients. These novel data suggest that lenalidomide functions to attenuate enhanced VWF clearance in AVWS. Interestingly, in a patient with MGUS, lenalidomide treatment was associated with a significant increase in plasma VWF levels, despite no major change in paraprotein level. Conclusions Collectively, our findings suggest that lenalidomide constitutes a novel therapeutic option for the management of AVWS associated with MG. The biological mechanism(s) through which lenalidomide causes a sustained increase in plasma VWF levels in AVWS independently of paraprotein level requires further study, but is in part modulated through inhibition of enhanced VWF clearance.

Bortezomib for the treatment of multiple myeloma

BACKGROUND

Multiple myeloma is a malignancy of plasma cells accounting for approximately 1% of cancers and 12% of haematological malignancies. The first-in-class proteasome inhibitor, bortezomib, is commonly used to treat newly diagnosed as well as relapsed/refractory myeloma, either as single agent or combined with other therapies.

OBJECTIVES

We conducted a systematic review and meta-analysis to assess the effects of bortezomib on overall survival (OS), progression-free survival (PFS), response rate (RR), health-related quality of life (HRQoL), adverse events (AEs) and treatment-related death (TRD).

SEARCH METHODS

We searched MEDLINE, the Cochrane Central Register of Controlled Trials and EMBASE (till 27 January 2016) as well as conference proceedings and clinical trial registries for randomised controlled trials (RCTs).

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that compared i) bortezomib versus no bortezomib with the same background therapy in each arm; ii) bortezomib versus no bortezomib with different background therapy in each arm or compared to other agent(s) and iii) bortezomib dose comparisons and comparisons of different treatment administrations and schedules.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted outcomes data and assessed risk of bias. We extracted hazard ratios (HR) and their confidence intervals for OS and PFS and odds ratios (OR) for response rates, AEs and TRD. We contacted trial authors to provide summary statistics if missing. We estimated Logrank statistics which were not available. We extracted HRQoL data, where available.

MAIN RESULTS

We screened a total of 3667 records, identifying 16 relevant RCTs involving 5626 patients and included 12 trials in the meta-analyses. All trials were randomised and open-label studies. Two trials were published in abstract form and therefore we were unable to assess potential risk of bias in full.There is moderate-quality evidence that bortezomib prolongs OS (four studies, 1586 patients; Peto OR 0.77, 95% CI 0.65 to 0.92) and PFS (five studies, 1855 patients; Peto OR 0.65, 95% CI 0.57 to 0.74) from analysing trials of bortezomib versus no bortezomib with the same background therapy in each arm.There is high-quality evidence that bortezomib prolongs OS (five studies, 2532 patients; Peto OR 0.76, 95% CI 0.67 to 0.88) but low-quality evidence for PFS (four studies, 2489 patients; Peto OR 0.67, 95% CI 0.61 to 0.75) from analysing trials of bortezomib versus no bortezomib with different background therapy in each arm or compared to other agent(s).Four trials (N = 716) examined different doses, methods of administrations and treatment schedules and were reviewed qualitatively only.We identified four trials in the meta-analysis that measured time to progression (TTP) and were able to extract and analyse PFS data for three of the studies, while in the case of one study, we included TTP data as PFS data were not available. We therefore did not analyse TTP separately in this review.Patients treated with bortezomib have increased risk of thrombocytopenia, neutropenia, gastro-intestinal toxicities, peripheral neuropathy, infection and fatigue with the quality of evidence highly variable. There is high-quality evidence for increased risk of cardiac disorders from analysing trials of bortezomib versus no bortezomib with different background therapy in each arm or versus other agents. The risk of TRD in either comparison group analysed is uncertain due to the low quality of the evidence.Only four trials analysed HRQoL and the data could not be meta-analysed.Subgroup analyses by disease setting revealed improvements in all outcomes, whereas for therapy setting, an improved benefit for bortezomib was observed in all outcomes and subgroups except for OS following consolidation therapy.

AUTHORS' CONCLUSIONS

This meta-analysis found that myeloma patients receiving bortezomib benefited in terms of OS, PFS and response rate compared to those who did not receive bortezomib. This benefit was observed in trials of bortezomib versus no bortezomib with the same background therapy and in trials of bortezomib versus no bortezomib with different background therapy in each arm or compared to other agent(s). Further evaluation of newer proteasome inhibitors is required to ascertain whether these agents offer an improved risk-benefit profile, while more studies of HRQoL are also required.

Comprehensive evaluation of poly(I:C) induced inflammatory response in an airway epithelial model

Respiratory viruses invade the upper airway of the lung, triggering a potent immune response that often exacerbates preexisting conditions such as asthma and COPD. Poly(I:C) is a synthetic analog of viral dsRNA that induces the characteristic inflammatory response associated with viral infection, such as loss of epithelial integrity, and increased production of mucus and inflammatory cytokines. Here, we explore the mechanistic responses to poly(I:C) in a well-defined primary normal human bronchial epithelial (NHBE) model that recapitulates in vivo functions and responses. We developed functional and quantifiable methods to evaluate the physiology of our model in both healthy and inflamed states. Through gene and protein expression, we validated the differentiation state and population of essential cell subtypes (i.e., ciliated, goblet, club, and basal cells) as compared to the human lung. Assays for total mucus production, cytokine secretion, and barrier function were used to evaluate in vitro physiology and response to viral insult. Cells were treated apically with poly(I:C) and evaluated 48 h after induction. Results revealed a dose-dependent increase in goblet cell differentiation, as well as, an increase in mucus production relative to controls. There was also a dose-dependent increase in secretion of IL-6, IL-8, TNF-α, and RANTES. Epithelial barrier function, as measured by TEER, was maintained at 1501 ± 355 Ω*cm² postdifferentiation, but dropped significantly when challenged with poly(I:C). This study provides first steps toward a well-characterized model with defined functional methods for understanding dsRNA stimulated inflammatory responses in a physiologically relevant manner.

DNA photoprotection conveyed by sunscreen

INTRODUCTION

Skin photoaging is the consequence of solar UV exposure, and DNA damage is an important part of this process. The objective of the current work was to demonstrate that in vitro skin models can be utilized to confirm that DNA damage protection is provided by sunscreens.

METHODS

Skin equivalents were exposed to full-spectrum UV light administered with a standard research solar simulator with and without pre-application of sunscreen. Cyclopyrimidine dimer (CPD) and sunburn cell (SBC) formation as well as CPD quantitation were evaluated to determine DNA damage protection provided by the sunscreen.

RESULTS

Marked decreases in both CPDs and SBCs were observed when sunscreen was applied prior to UV exposure.

CONCLUSIONS

Sunscreen application prior to full-spectrum solar UV exposure protects DNA from photodamage measured by CPD and SBC formation. This can be expected to lessen the risk of photoaging and malignant transformation.

CaMKII is essential for the proasthmatic effects of oxidation

Increased reactive oxygen species (ROS) contribute to asthma, but little is known about the molecular mechanisms connecting increased ROS with characteristic features of asthma. We show that enhanced oxidative activation of the Ca(2+)/calmodulin-dependent protein kinase (ox-CaMKII) in bronchial epithelium positively correlates with asthma severity and that epithelial ox-CaMKII increases in response to inhaled allergens in patients. We used mouse models of allergic airway disease induced by ovalbumin (OVA) or Aspergillus fumigatus (Asp) and found that bronchial epithelial ox-CaMKII was required to increase a ROS- and picrotoxin-sensitive Cl(-) current (ICl) and MUC5AC expression, upstream events in asthma progression. Allergen challenge increased epithelial ROS by activating NADPH oxidases. Mice lacking functional NADPH oxidases due to knockout of p47 and mice with epithelial-targeted transgenic expression of a CaMKII inhibitory peptide or wild-type mice treated with inhaled KN-93, an experimental small-molecule CaMKII antagonist, were protected against increases in ICl, MUC5AC expression, and airway hyperreactivity to inhaled methacholine. Our findings support the view that CaMKII is a ROS-responsive, pluripotent proasthmatic signal and provide proof-of-concept evidence that CaMKII is a therapeutic target in asthma.

An immunophenotypic and molecular diagnosis of composite hairy cell leukaemia and chronic lymphocytic leukaemia

Hairy cell leukaemia (HCL) and chronic lymphocytic leukaemia (CLL) are distinct clinicopathological B cell chronic lymphoproliferative disorders (B-CLPD). Both diseases have characteristic immunophenotypic and molecular features. The co-existence of two B-CLPD is perhaps more common than previously thought but a composite HCL and CLL has been rarely documented. A case is reported in which the morphology, integrated with an extensive immunophenotyping panel, and incorporation of the recently described HCL-associated BRAF V600E mutation, enabled the prompt diagnosis of composite HCL and CLL thus allowing appropriate treatment selection. This case serves to highlight the benefit of a multidisciplinary approach to the diagnosis of bi-clonal B-CLPD.

Full Thickness EpiDerm: a dermal-epidermal skin model to study epithelial-mesenchymal interactions

Unlike previous dermal-epidermal models, Full Thickness EpiDerm is cultured in an easily manipulated cell culture insert, and the tissue extends from wall to wall. In terms of ease of use, these characteristics greatly facilitate the testing of potential allergens or irritants in that direct topical application is possible. Topical exposure to the common surfactant, 1% Triton X-100, resulted in MTT tissue viability dose-response curves that fell within the normal range of the keratinocyte-only tissue, EpiDerm. Currently, in order to produce a standardised, reproducible organotypic tissue, all lots of EpiDerm are compared to a reference database of effective time-50 (ET-50) values, i.e. the time of exposure after which viability is reduced to 50% following exposure to 100 microl of Triton X-100. The database average (184 tissue lots) is 6.74 +/- 0.99 hours (+/- 1 SD); initial lots of the full thickness tissue, tested in an identical manner, averaged 7.79 +/- 1.24 hours (n = 11). Histological cross-sections of the full thickness tissue showed an epidermal layer that is very similar to EpiDerm and native epidermis on a fibroblast-containing collagen matrix dermis-like layer. Irradiation of the tissue with ultraviolet light induced an increase in collagenase (MMP-1) release. Based on these initial results, investigation of the tissue response to stimuli specifically affecting the dermis or epidermal/dermal "cross-talk" will probably prove informative.

Novel technologies and an overall strategy to allow hazard assessment and risk prediction of chemicals, cosmetics, and drugs with animal-free methods

Several alternative methods to replace animal experiments have been accepted by legal bodies. An even larger number of tests are under development or already in use for non-regulatory applications or for the generation of information stored in proprietary knowledge bases. The next step for the use of the different in vitro methods is their combination into integrated testing strategies (ITS) to get closer to the overall goal of predictive "in vitro-based risk evaluation processes." We introduce here a conceptual framework as the basis for future ITS and their use for risk evaluation without animal experiments. The framework allows incorporation of both individual tests and already integrated approaches. Illustrative examples for elements to be incorporated are drawn from the session "Innovative technologies" at the 8th World Congress on Alternatives and Animal Use in the Life Sciences, held in Montreal, 2011. For instance, LUHMES cells (conditionally immortalized human neurons) were presented as an example for a 2D cell system. The novel 3D platform developed by InSphero was chosen as an example for the design and use of scaffold-free, organotypic microtissues. The identification of critical pathways of toxicity (PoT) may be facilitated by approaches exemplified by the MatTek 3D model for human epithelial tissues with engineered toxicological reporter functions. The important role of in silico methods and of modeling based on various pre-existing data is demonstrated by Altamira's comprehensive approach to predicting a molecule's potential for skin irritancy. A final example demonstrates how natural variation in human genetics may be overcome using data analytic (pattern recognition) techniques borrowed from computer science and statistics. The overall hazard and risk assessment strategy integrating these different examples has been compiled in a graphical work flow.

GF-15, a novel inhibitor of centrosomal clustering, suppresses tumor cell growth in vitro and in vivo

In contrast to normal cells, malignant cells are frequently aneuploid and contain multiple centrosomes. To allow for bipolar mitotic division, supernumerary centrosomes are clustered into two functional spindle poles in many cancer cells. Recently, we have shown that griseofulvin forces tumor cells with supernumerary centrosomes to undergo multipolar mitoses resulting in apoptotic cell death. Here, we describe the characterization of the novel small molecule GF-15, a derivative of griseofulvin, as a potent inhibitor of centrosomal clustering in malignant cells. At concentrations where GF-15 had no significant impact on tubulin polymerization, spindle tension was markedly reduced in mitotic cells upon exposure to GF-15. Moreover, isogenic cells with conditional centrosome amplification were more sensitive to GF-15 than parental controls. In a wide array of tumor cell lines, mean inhibitory concentrations (IC(50)) for proliferation and survival were in the range of 1 to 5 μmol/L and were associated with apoptotic cell death. Importantly, treatment of mouse xenograft models of human colon cancer and multiple myeloma resulted in tumor growth inhibition and significantly prolonged survival. These results show the in vitro and in vivo antitumor efficacy of a prototype small molecule inhibitor of centrosomal clustering and strongly support the further evaluation of this new class of molecules.

Abstract 660: Inhibition of centrosomal clustering suppresses tumor growth in vivo

Tumor cells frequently contain multiple centrosomes, associated with the formation of multipolar mitotic spindles and chromosome segregation defects. To allow for bipolar mitotic division, supernumerary centrosomes are clustered into two functional spindle poles (centrosomal clustering). We recently described a phenotype-based small molecule screening strategy directed to induce tumor cells with supernumerary centrosomes to undergo multipolar mitoses, thereby resulting in apoptotic cell death (Rebacz et al., Cancer Res 2007; 67: 6342-6350). We here describe the novel small molecule GF-15, a derivative of griseofulvin and a potent inhibitor of centrosomal clustering, thereby inducing multipolar spindles followed by apoptosis. We tested more than 25 cancer cell lines from hematologic malignancies (including acute and chronic leukemias, lymphomas), solid tumors (including glioblastoma, colon, cervix, and pancreatic cancers) and a wide array of myeloma cell lines. We found mean inhibitory concentrations (IC50) for proliferation and survival in the range of 1-5μM GF-15, associated with activation of caspases 8, 9, and 3. As expected, tumor cell lines displaying only limited centrosomal aberrations or microsatellite instability were less sensitive to treatment with GF-15. Importantly, non-malignant cells without supernumerary centrosomes including PBMCs, immortalized hepatocytes, and bone marrow stromal cells, did not reach their IC50 even at 30μM GF-15. Specifically, cell cycle analysis of synchronized myeloma cells showed marked G2/M arrest, followed by a dramatic increase of the sub-G1 fraction, after treatment with GF-15. In addition, treatment with GF-15 was associated with inhibition of VEGF- and IGF1-triggered myeloma cell migration. Pharmakodynamic studies in vivo revealed rapid renal clearance of GF-15 and metabolites within 6 hours p.i. No acute or chronic toxicity was observed. Finally, both intraperitoneal and oral GF-15 treatment of murine xenograft models of human multiple myeloma resulted in tumor growth inhibition and significantly prolonged survival associated with significant increase of aberrant mitoses in vivo. Taken together, our results demonstrate the in vitro and in vivo anti-tumor efficacy of the first in class small molecule inhibitor of centrosomal clustering with specificity for tumor cells, and strongly support its clinical evaluation to improve patient outcome in both hematologic malignancies and solid tumors.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 660. doi:10.1158/1538-7445.AM2011-660