Interstitial flow potentiates TGF-ß/Smad-signaling activity in lung cancer spheroids in a 3D-microfluidic chip.

Within the tumor microenvironment (TME), cancer cells use mechanotransduction pathways to convert biophysical forces to biochemical signals. However, the underlying mechanisms and functional significance of these pathways remain largely unclear. The upregulation of mechanosensitive pathways from biophysical forces such as interstitial flow (IF), leads to the activation of various cytokines, including transforming growth factor-ß (TGF-ß). TGF-ß promotes in part via a Smad-dependent signaling pathway the epithelial-mesenchymal transition (EMT) in cancer cells. The latter process is linked to increased cancer cell motility and invasion. Current research models have limited ability to investigate the combined effects of biophysical forces (such as IF) and cytokines (TGF-ß) in a 3D microenvironment. We used a 3D-matrix based microfluidic platform to demonstrate the potentiating effect of IF on exogenous TGF-ß induced upregulation of the Smad-signaling activity and the expression of mesenchymal marker vimentin in A549 lung cancer spheroids. To monitor this, we used stably integrated fluorescent based reporters into the A549 cancer cell genome. Our results demonstrate that IF enhances exogenous TGF-ß induced Smad-signaling activity in lung cancer spheroids embedded in a matrix microenvironment. In addition, we observed an increased cell motility for A549 spheroids when exposed to IF and TGF-ß. Our 3D-microfluidic model integrated with real-time imaging provides a powerful tool for investigating cancer cell signaling and motility associated with invasion characteristics in a physiologically relevant TME.

Evaluation of Novel Targets, Including CC-Chemokine Receptor 4, in Adult T-Cell Acute Lymphoblastic Leukemia/Lymphoma: A Mayo Clinic Clinical and Pathologic Study.

CONTEXT.­: Unlike B-cell acute lymphoblastic leukemia/lymphoma (ALL/LBL), there have been few therapeutic advances in T-cell ALL (T-ALL)/LBL, an aggressive ALL/LBL subtype. OBJECTIVE.­: To perform a focused tissue array study to elucidate tumor markers of therapeutic potential in T-ALL/LBL. DESIGN.­: Using immunohistochemistry, we evaluated expression of leukemic antigens of interest, specifically CC-chemokine receptor 4 (CCR4), among others, on available remnant diagnostic material, including tumor tissue slides obtained from formalin-fixed, paraffin-embedded preserved tissues. RESULTS.­: Our analysis identified, for the first time, expression of CCR4 in T-ALL/LBL in 11 of 27 cases (40.7%) and confirmed common expression of BCL2, CD38, and CD47, as reported previously. We also identified the expression of CD123 in 4 of 26 cases (15.4%), whereas BCL6 and PDL1 were expressed in a small number of T-ALL/LBL cases. The potential novel target CCR4 was significantly more common in the Pre/Pro-T immunophenotypic subtype, 6 of 9 (66.7%, P = .01). No additional differences in clinical and epidemiologic variables were noted among positive or negative CCR4 cases. CONCLUSIONS.­: These findings support preclinical and clinical testing of therapies targeting CCR4, CD47, BCL2, CD38, and CD123 in T-ALL/LBL, and may help guide the development of targeted clinical trials in T-ALL/LBL, a rare disease in urgent need of novel therapies.

SOHO State of the Art Updates and Next Questions | Philadelphia Chromosome Positive Acute Lymphoblastic Leukemia in Adults: Therapeutic Options and Challenges in 2023.

The therapeutic landscape of Philadelphia chromosome positive acute lymphoblastic leukemia (ALL) for adults has dramatically changed over the past 2 decades; the emergence of newer generations of tyrosine kinase inhibitors and incorporation of targeted immunotherapies into front-line therapy have significantly improved outcomes to the point where an argument can be made that this entity may no longer be considered a high-risk ALL subgroup. In this review article, we discuss different front-line regimens (both intensive and deintensified regimens including chemotherapy-free regimens). We also review disease monitoring strategies, discuss the role of allogeneic hematopoietic stem cell transplantation, and discuss the rapidly changing therapeutic landscape for patients with relapsed disease.

Outcomes of Patients with Thrombocytopenia Evaluated at Hematology Subspecialty Clinics.

BACKGROUND: Thrombocytopenia is a frequently encountered laboratory abnormality and a common reason for hematology referrals. Workup for thrombocytopenia is not standardized and frequently does not follow an evidence-based algorithm. We conducted a systematic analysis to evaluate the laboratory testing and outcomes of patients evaluated for thrombocytopenia at hematology clinics in a tertiary referral center between 2013 and 2016. PATIENT AND METHODS: We performed a comprehensive chart review for patients evaluated for thrombocytopenia during the study period. Patients were followed for 1 year from the initial hematology evaluation and assessed for the development of a hematologic malignancy, rheumatologic, or infectious diseases among other clinical outcomes. RESULTS: We evaluated 472 patients with a median (range) age of 61 (17-94) years. The majority (63.8%) had mild thrombocytopenia. Within 1 year of follow-up, 14 patients (3.0%) were diagnosed with a hematologic malignancy. A higher likelihood of developing a hematologic malignancy was noted in patients with concurrent leukopenia (hazard ratio [HR] 9.97, 95% confidence interval [CI] 3.28-30.32, p < .01) and increasing age (HR per 10-year deciles 1.52, 95% CI 1.03-2.25, p = .03). In patients with asymptomatic isolated mild thrombocytopenia, laboratory testing did not reveal any significant positive findings and patients did not receive any new major diagnosis during the follow-up period. CONCLUSION: Our findings provide basis and call for development of an evidence-based algorithmic approach for evaluation of patients with thrombocytopenia, testing, and referrals. It also supports a conservative approach mainly driven by physical exam signs, symptoms, and other laboratory findings for patients with isolated mild thrombocytopenia.

Predictors and Management of Relapse to Axicabtagene Ciloleucel in Patients with Aggressive B-cell Lymphoma.

OBJECTIVE/BACKGROUND: Despite the success of chimeric antigen receptor (CAR) T-cell therapy in patients with aggressive non-Hodgkin lymphoma (aNHL), some patients still fail treatment, and their prognosis is dismal. METHODS: We performed a retrospective study of aNHL patients treated with axicabtagene ciloleucel (axi-cel) at two Mayo Clinic centers between 2018 and 2020. We evaluated predictive factors, toxicities, and responses to salvage regimens after CAR T-cell therapy. RESULTS: Thirty-four patients received axi-cel with a median length of hospitalization of 14 days. Cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome of any grade occurred in 91% and 41% of patients, respectively. Furthermore, 71% of patients responded to therapy, with 53% achieving a complete response (CR). The CRS grade and absolute lymphocyte count at leukapheresis (ALCLeuk) correlated with CR and overall survival (OS), respectively. After a median follow-up of 6.8 months (interquartile range [IQR] 4.6-14.9), 15 patients (44%) showed progressive disease (PD). Most patients (60%) progressed during the first 3 months and had persistent CD19 tumor expression. Elevated C-reactive protein at baseline increased the risk of PD, whereas elevated ferritin increased PD and mortality risk. Twelve patients received salvage therapy, but only three responded. Median OS of relapsed/refractory patients to axi-cel was 3 months (IQR 1.3-5.1). CONCLUSION: The grade of CRS and ALCLeuk correlated with better outcomes to axi-cel therapy. In addition, elevated inflammatory markers at baseline were associated with PD and shorter survival. Relapses after treatment frequently occur within months after axi-cel infusion; they confer a poor prognosis and create an urgent need for novel and effective treatment options in this patient population.

Microfluidic evidence of synergistic effects between mesenchymal stromal cell-derived biochemical factors and biomechanical forces to control endothelial cell function.

A functional vascular system is a prerequisite for bone repair as disturbed angiogenesis often causes non-union. Paracrine factors released from human bone marrow derived mesenchymal stromal cells (BMSCs) have angiogenic effects on endothelial cells. However, whether these paracrine factors participate in blood flow dynamics within bone capillaries remains poorly understood. Here, we used two different microfluidic designs to investigate critical steps during angiogenesis and found pronounced effects of endothelial cell proliferation as well as chemotactic and mechanotactic migration induced by BMSC conditioned medium (CM). The application of BMSC-CM in dynamic cultures demonstrates that bioactive factors in combination with fluidic flow-induced biomechanical signals significantly enhanced endothelial cell migration. Transcriptional analyses of endothelial cells demonstrate the induction of a unique gene expression profile related to tricarboxylic acid cycle and energy metabolism by the combination of BMSC-CM factors and shear stress, which opens an interesting avenue to explore during fracture healing. Our results stress the importance of in vivo - like microenvironments simultaneously including biochemical, biomechanical and oxygen levels when investigating key events during vessel repair. STATEMENT OF SIGNIFICANCE: Our results demonstrate the importance of recapitulating in vivo - like microenvironments when investigating key events during vessel repair. Endothelial cells exhibit enhanced angiogenesis characteristics when simultaneous exposing them to hMSC-CM, mechanical forces and biochemical signals simultaneously. The improved angiogenesis may not only result from the direct effect of growth factors, but also by reprogramming of endothelial cell metabolism. Moreover, with this model we demonstrated a synergistic impact of mechanical forces and biochemical factors on endothelial cell behavior and the expression of genes involved in the TCA cycle and energy metabolism, which opens an interesting new avenue to stimulate angiogenesis during fracture healing.

Microfluidics meets 3D cancer cell migration.

An early step of metastasis requires a complex and coordinated migration of invasive tumor cells into the surrounding tumor microenvironment (TME), which contains extracellular matrix (ECM). It is being appreciated that 3D matrix-based microfluidic models have an advantage over conventional in vitro and animal models to study tumor progression events. Recent microfluidic models have enabled recapitulation of key mechanobiological features present within the TME to investigate collective cancer cell migration and invasion. Microfluidics also allows for functional interrogation and therapeutic manipulation of specific steps to study the dynamic aspects of tumor progression. In this review, we focus on recent developments in cancer cell migration and how microfluidic strategies have evolved to address the physiological complexities of the TME to visualize migration modes adapted by various tumor cells.

Incidence of thrombosis in relapsed/refractory B-cell lymphoma treated with axicabtagene ciloleucel: Mayo Clinic experience.

Chimeric antigen receptor (CAR) T-cell therapy is effective in relapsed/refractory large B-cell lymphoma and results in a unique toxicity profile, namely cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome. The hyper-inflammatory state associated with these toxicities has been suggested to increase the risk of thrombosis. We conducted a retrospective analysis of patients treated with axicabtagene ciloleucel (axi-cel) to assess the rate of thrombosis with axi-cel therapy from the time of CAR T-cell infusion until the end of hospitalization, when performed in the inpatient setting, or up to day +30 when performed in the outpatient setting. Ninety-two (95%) of 97 patients were hospitalized during axi-cel therapy and 85 (88%) developed CRS. Fifty-five patients (57%) received concurrent anticoagulation (53 as prophylaxis). Patients with prior VTE did not have progression or evidence of new VTE. Only 2 (2.1%) patients developed VTE. These results demonstrate a low-risk for thrombosis in axi-cel recipients.

Spectrometric Analysis of the Wear from Metallic and Ceramic Dental Implants following Insertion: An In Vitro Study.

Titanium wear is a growing area of interest within dental implantology. This study aimed to investigate titanium and zirconium wear from dental implants at the time of insertion using X-ray-fluorescence spectrometry (XRF) and an in vitro protocol utilizing artificial bovine bone plates. Five groups were analyzed using XRF-spectrometry: groups 1-4 (titanium implants) and group 5 (zirconia implants). The implants were inserted into two bone blocks held together by a vice. The blocks were separated, and the insertion sites were analyzed for titanium (Ti) and zirconium (Zr). Statistical descriptive analyses of Ti and Zr concentrations in the coronal, middle and apical bone interface were performed. A comparative analysis confirmed differences between the implant's surface stability and Ti accumulation within the insertion sites of the bone block. There was a direct relationship between implant length and the quantity of titanium found on the bone block. The data generally indicates greater quantities of titanium in the coronal thirds of the implants, and less in the apical thirds. The titanium and zirconium found in the bone samples where the group 5 implants were inserted was not of statistical significance when compared to control osteotomies. The results of this study confirm wear from metallic, but not ceramic, dental implants at the time of insertion.

Gilteritinib clinical activity in relapsed/refractory FLT3 mutated acute myeloid leukemia previously treated with FLT3 inhibitors.

Gilteritinib is approved for the treatment of relapsed/refractory (R/R) acute myeloid leukemia (AML) with an FLT3-mutation (FLT3mut+ ). However, the gilteritinib phase 3 ADMIRAL study (Perl et al NEJM 2019) was conducted prior to widespread adoption of either midostaurin as a component of standard intensive induction and consolidation or posttransplant FLT3 inhibitor maintenance. We performed a retrospective analysis using data from 11 US centers and where we identified 113 patients who received gilteritinib alone or as combination therapy for the treatment of R/R FLT3mut+ AML. The composite complete remission (CR) rate (CRc, defined as CR + CRi + CR with incomplete platelet recovery [CRp]) was 48.7% (n = 55). The CRc rate after treatment with gilteritinib in patients who were treated with only prior 7+3 and midostaurin with or without consolidation was 58% with a median survival of 7.8 months. Survival was longest in patients who obtained a CR, particularly a cMRD (clinical minimal or measurable residual disease) negative response; this remained significant after censoring at the time of stem cell transplant. The mitogen-activated protein kinase pathway activating mutations that are known for gilteritinib resistance (NRAS, KRAS, and PTPN11) had lower CRc (35% vs. 60.5%) and lower median overall survival than patients' whose leukemia did not express these mutations (4.9 months vs. 7.8 months) (HR 2.4; 95% CI 1. 5.4) p value <.01.

Comparative study of therapy-related and de novo adult b-cell acute lymphoblastic leukaemia.

We report a comparative analysis of patients with therapy-related acute lymphoblastic leukaemia (tr-ALL) vs de novo ALL. We identified 331 patients with B-ALL; 69 (21%) were classified as tr-ALL. The most common prior malignancies were breast (23·2%) and plasma cell disorders (20·3%). Patients with tr-ALL were older (median 63·2 vs. 46·2 years, P < 0.001), more often female (66·7% vs. 43·5%, P < 0·001), and more likely to have hypodiploid cytogenetics (18·8% vs. 5·0%, P < 0·001). In multivariable analysis, patients with tr-ALL were less likely to achieve complete remission [odds ratio (OR) = 0·16, P < 0·001] and more likely to be minimal residual disease-positive (OR = 4·86, P = 0·01) but had similar OS after diagnosis and allo-haematopoietic cell transplantation.

Primary peritoneal myeloid sarcoma in association with CBFB/MYH11 fusion.

Myeloid sarcoma, also known as chloroma or granulocytic sarcoma is an extramedullary disease process that typically presents in association with acute myeloid leukemia during initial presentation or at relapse. Often associated with cytogenetic mutations, including t(8;21)(q22;q22); RUNX1/RUNX1T1, and less frequently with inv(16)(p13.1q22) or t(16;16)(p13.1;q22); CBFB/MYH11, myeloid sarcoma is most commonly discovered in skin, soft tissue, bone, and connective tissue. In rare circumstances, myeloid sarcoma can present without any evidence of bone marrow or leukemic involvement. These cases of de novo myeloid sarcoma are rare, and are commonly misdiagnosed due to similarities with other entities. We report an unusual case of a primary de novo peritoneal myeloid sarcoma, in association with inv(16)(p13;q22) and clonal heterogeneity at different sites of involvement, that has responded well to AML induction therapy and consolidation treatment with gemtuzumab ozogamicin and high dose cytarabine. Cytogenetics, immunophenotyping, and chromosomal analysis, were each critical in establishing a proper diagnosis as well as helping to develop appropriate therapeutic strategies for this rare entity.

Impact of Novel Targeted Therapies and Cytogenetic Risk Groups on Outcome After Allogeneic Transplantation for Adult ALL.

Novel high-risk groups have recently been identified in adult acute lymphoblastic leukemia (ALL), including Philadelphia-like, therapy-related, and measurable residual disease after induction therapy. Furthermore, modern targeted therapies have recently been incorporated into ALL management; rituximab for CD20-positive and blinatumomab for measurable residual disease after induction therapy or relapsed or refractory disease. Allogeneic hematopoietic cell transplantation (allo-HCT) is recommended as consolidation therapy for high-risk ALL; however, its relative benefit for these high-risk groups and after novel therapies is unclear. We performed an analysis of posttransplantation outcomes in a cohort of 261 consecutive patients who underwent allo-HCT for ALL at the 3-site Mayo Clinic Cancer Center (January 1, 2008-December 31, 2018). With a median (range) follow-up of 22.4 months (0.5-135.0), the 100-day and 5-year cumulative incidences of nonrelapse mortality rates were 6.5% and 26.7%, respectively. The 5-year cumulative incidences of relapse and death were 22.6% and 46.2%, respectively. The 1-year estimate of the composite endpoint of graft-versus-host disease/relapse-free survival was 39.3%. We observed no associations of novel high-risk groups or modern targeted therapies with overall survival, nonrelapse mortality, or relapse in multivariable analysis. An increased risk of relapse was observed with T-ALL (hazard ratio, 2.16; 95% confidence interval, 1.14-4.09; P = .02) and hypodiploidy/near-triploidy (hazard ratio, 2.84; 95% confidence interval, 1.06-7.62; P = .04). Our analysis suggests that novel high-risk groups derive a similar benefit from allo-HCT as traditional high-risk adult ALL and that novel targeted therapies do not seem to independently predict for posttransplantation outcomes. It also calls for further exploration of maintenance strategies after Allo-HCT to prevent relapse in high-risk subgroups.

Impact of hypoalbuminemia on the prognosis of relapsed/refractory B-cell lymphoma treated with axicabtagene ciloleucel.

INTRODUCTION: Hypoalbuminemia is a known adverse prognostic factor in lymphomas. Yet, it is unknown if axicabtagene ciloleucel (axi-cel) overcomes the adverse prognostic impact of hypoalbuminemia in relapsed/refractory large B-cell lymphoma. METHODS: We conducted a retrospective analysis across three Mayo Clinic centers to assess the relationship of hypoalbuminemia (defined as a serum albumin (SA) levels ≤ 3.5 g/dL) on outcomes of patients treated with axi-cel. RESULTS: This analysis included 81 patients. Two patients had no available SA levels preceding axi-cel infusion. Eighteen patients (22.8%) had hypoalbuminemia with a median SA of 3.3 g/dL. Patients with normal SA had a statistically higher ORR than those without hypoalbuminemia (P = .018). There was no difference in 1-year PFS and OS between the group with hypoalbuminemia and the group with normal SA levels (48% vs 49%, P = .81) and (74% vs 73%, P = .97), respectively. There was no difference in the severity or median duration of cytokine release syndrome or neurotoxicity between the two groups. CONCLUSION: Notwithstanding the limitations related to the relatively small sample size, axi-cel therapy appears to overcome the adverse effect of hypoalbuminemia on OS and PFS. Large multicenter clinical studies are certainly needed to validate these findings.

C-reactive protein and ferritin levels and length of intensive care unit stay in patients with B-cell lymphomas treated with axicabtagene ciloleucel.

OBJECTIVE/BACKGROUND: Chimeric antigen receptor (CAR) T-cell is an effective therapy in relapsed/refractory large B-cell lymphomas that, due to its unique toxicities, often requires escalation of care to the intensive care unit (ICU) setting. C-reactive protein (CRP) and ferritin are serum inflammatory markers associated with onset and persistence of CAR T-cell-related toxicity. METHODS: We retrospectively analyzed 34 patients treated with axicabtagene ciloleucel (axi-cel) who were divided into two groups: patients requiring admission to the ICU during initial hospitalization (n = 13, 38%) and those who did not (n = 21, 62%). Primary objective was to examine possible relationships between serum ferritin and/or CRP levels with the need for, and length of, ICU stay between these groups. RESULTS: All 13 patients admitted to the ICU developed cytokine release syndrome (CRS) and 11 of them also developed neurotoxicity (NT). Of the 21 patients in the non-ICU group, 18 developed CRS and 5 patients developed NT. Grade of CRS and NT were higher in ICU versus non-ICU patients (p = .03 and .001, respectively). There was no correlation between CRP levels at time of ICU admission and length of ICU stay (correlation of 0.41, p = .17). Yet, there was an association between serum ferritin levels and length of ICU stay (R2 = 0.73) which did not reach statistical significance (correlation of 0.21, p = .49). CONCLUSION: Notwithstanding the limitations of the small sample size, our study suggests that an elevated ferritin level at the time of escalation of medical care may be possibly indicative of anticipated prolonged ICU hospitalization in patients treated with axi-cel. A large multicenter study is certainly needed to confirm this observation.

Donor cell-derived chronic myelomonocytic leukemia presenting after allogeneic hematopoietic cell transplantation for T-cell acute lymphoblastic leukemia.

Donor cell leukemia is a very rare cause of relapse after allogeneic hematopoietic cell transplantation (alloHCT). Herein, we describe an unprecedented case of donor cell-derived chronic myelomonocytic leukemia (CMML) presenting seven years after a 51-year-old man received a matched-related alloHCT from his 59-year-old brother for T-cell acute lymphoblastic leukemia.