Leukemia Therapy Research Articles

Lysosome-Disrupting Agents in Combination with Venetoclax Increase Apoptotic Response in Primary Chronic Lymphocytic Leukemia (CLL) Cells Mediated by Lysosomal Cathepsin D Release and Inhibition of Autophagy.

Venetoclax and obinutuzumab are becoming frontline therapies for chronic lymphocytic leukemia (CLL) patients. Unfortunately, drug resistance still occurs, and the combination could be immunosuppressive. Lysosomes have previously been identified as a target for obinutuzumab cytotoxicity in CLL cells, but the mechanism remains unclear. In addition, studies have shown that lysosomotropic agents can cause synergistic cell death in vitro when combined with the BTK inhibitor, ibrutinib, in primary CLL cells. This indicates that targeting lysosomes could be a treatment strategy for CLL. In this study, we have shown that obinutuzumab induces lysosome membrane permeabilization (LMP) and cathepsin D release in CLL cells. Inhibition of cathepsins reduced obinutuzumab-induced cell death in CLL cells. We further determined that the lysosomotropic agent siramesine in combination with venetoclax increased cell death in primary CLL cells through an increase in reactive oxygen species (ROS) and cathepsin release. Siramesine treatment also induced synergistic cytotoxicity when combined with venetoclax. Microenvironmental factors IL4 and CD40L or incubation with HS-5 stromal cells failed to significantly protect CLL cells from siramesine- and venetoclax-induced apoptosis. We also found that siramesine treatment inhibited autophagy through reduced autolysosomes. Finally, the autophagy inhibitor chloroquine failed to further increase siramesine-induced cell death. Taken together, lysosome-targeting drugs could be an effective strategy in combination with venetoclax to overcome drug resistance in CLL.

Advancements in small interfering RNAs therapy for acute lymphoblastic leukemia: promising results and future perspectives.

Acute lymphoblastic leukemia (ALL) is the most common type of cancer among children, presenting significant healthcare challenges for some patients, including drug resistance and the need for targeted therapies. SiRNA-based therapy is one potential solution, but problems can arise in administration and the need for a delivery system to protect siRNA during intravenous injection. Additionally, siRNA encounters instability and degradation in the reticuloendothelial system, off-target effects, and potential immune system stimulation. Despite these limitations, some promising results about siRNA therapy in ALL patients have been published in recent years, showing the potential for more effective and precise treatment, reduced side effects, and personalized approaches. While siRNA-based therapies demonstrate safety and efficacy, addressing the mentioned limitations is crucial for further optimization. Advancements in siRNA-delivery technologies and combination therapies hold promise to improve treatment effectiveness and overcome drug resistance. Ultimately, despite its challenges, siRNA therapy has the potential to revolutionize ALL treatments and improve patient outcomes.

Association of Vitamin A and D Deficiencies with Infectious Outcomes in Children Undergoing Intensive Induction Therapy for Acute Lymphoblastic Leukemia

To evaluate the association between deficiency of vitamin A or D at diagnosis of pediatric acute lymphoblastic leukemia (ALL) and subsequent infectious complications during induction therapy. We conducted an institutional review board-approved, retrospective cohort study of children with newly diagnosed ALL from 2007 to 2017 at St. Jude Children's Research Hospital. We measured vitamin D, vitamin D binding protein, retinol binding protein as a surrogate for vitamin A, and immunoglobulin isotypes in serum obtained at ALL diagnosis, and we assessed the association between vitamin deficiencies or levels and infection-related complications during the 6-week induction phase using Cox regression models. Among 378 evaluable participants, vitamin A and D deficiencies were common (43% and 17%, respectively). Vitamin D deficiency was associated with higher risks of febrile neutropenia (adjusted hazard ratio [aHR], 1.7; P=.0072), clinically documented infection (aHR, 1.73; P=.025), and likely bacterial infection (aHR, 1.86; P=.008). Conversely, vitamin A deficiency was associated solely with a lower risk of sepsis (aHR, 0.19; P=.027). In this retrospective study, vitamin D deficiency was associated with an increased risk of common infection-related complications during induction therapy for ALL. Additional studies are warranted to evaluate whether vitamin D supplementation could mitigate this effect.

CXCR4-Mediated Codelivery of FLT3 and BCL-2 Inhibitors for Enhanced Targeted Combination Therapy of FLT3-ITD Acute Myeloid Leukemia.

Acute myeloid leukemia (AML) is often associated with poor prognosis and survival. Small molecule inhibitors, though widening the treatment landscape, have limited monotherapy efficacy. The combination therapy, however, shows suboptimal clinical outcomes due to low bioavailability, overlapping systemic toxicity and drug resistance. Here, we report that CXCR4-mediated codelivery of the BCL-2 inhibitor venetoclax (VEN) and the FLT3 inhibitor sorafenib (SOR) via T22 peptide-tagged disulfide cross-linked polymeric micelles (TM) achieves synergistic treatment of FLT3-ITD AML. TM-VS with a VEN/SOR weight ratio of 1/4 and T22 peptide density of 20% exhibited an extraordinary inhibitory effect on CXCR4-overexpressing MV4-11 AML cells. TM-VS at a VEN/SOR dosage of 2.5/10 mg/kg remarkably reduced leukemia burden, prolonged mouse survival, and impeded bone loss in orthotopic MV4-11-bearing mice, outperforming the nontargeted M-VS and oral administration of free VEN/SOR. CXCR4-mediated codelivery of BCL-2 and FLT3 inhibitors has emerged as a prospective clinical treatment for FLT3-ITD AML.

Alendronate/lactoferrin-dual decorated lipid nanocarriers for bone-homing and active targeting of ivermectin and methyl dihydrojasmonate for leukemia

Chronic myeloid leukemia is a hematological cancer, where disease relapse and drug resistance are caused by bone-hosted-residual leukemia cells. An innovative resolution is bone-homing and selective-active targeting of anticancer loaded-nanovectors. Herein, ivermectin (IVM) and methyl dihydrojasmonate (MDJ)-loaded nanostructured lipid carriers (IVM-NLC) were formulated then dually decorated by lactoferrin (Lf) and alendronate (Aln) to optimize (Aln/Lf/IVM-NLC) for active-targeting and bone-homing potential, respectively. Aln/Lf/IVM-NLC (1 mg) revealed nano-size (73.67 ± 0.06 nm), low-PDI (0.43 ± 0.06), sustained-release of IVM (62.75 % at 140-h) and MDJ (78.7 % at 48-h). Aln/Lf/IVM-NLC afforded substantial antileukemic-cytotoxicity on K562-cells (4.29-fold lower IC50), higher cellular uptake and nuclear fragmentation than IVM-NLC with acceptable cytocompatibility on oral-epithelial-cells (as normal cells). Aln/Lf/IVM-NLC effectively upregulated caspase-3 and BAX (4.53 and 15.9-fold higher than IVM-NLC, respectively). Bone homing studies verified higher hydroxyapatite affinity of Aln/Lf/IVM-NLC (1 mg; 22.88 ± 0.01 % at 3-h) and higher metaphyseal-binding (1.5-fold increase) than untargeted-NLC. Moreover, Aln/Lf/IVM-NLC-1 mg secured 1.35-fold higher in vivo bone localization than untargeted-NLC, with lower off-target distribution. Ex-vivo hemocompatibility and in-vivo biocompatibility of Aln/Lf/IVM-NLC (1 mg/mL) were established, with pronounced amelioration of hepatic and renal toxicity compared to higher Aln doses. The innovative Aln/Lf/IVM-NLC could serve as a promising nanovector for bone-homing, active-targeted leukemia therapy.

Optimization of In Vitro Th17 Polarization for Adoptive Cell Therapy in Chronic Lymphocytic Leukemia.

Although preclinical investigations have shown notable efficacy in solid tumor models utilizing in vitro-differentiated Th17 cells for adoptive cell therapy (ACT), the potential benefits of this strategy in enhancing ACT efficacy in hematological malignancies, such as chronic lymphocytic leukemia (CLL), remain unexplored. CLL is a B-cell malignancy with a clinical challenge of increased resistance to targeted therapies. T-cell therapies, including chimeric antigen receptor (CAR) T cells, have demonstrated limited success in CLL, which is attributed to CLL-mediated T-cell dysfunction and skewing toward immunosuppressive phenotypes. Herein, we illustrate the feasibility of polarizing CD4+ T cells from the Eμ-TCL1 murine model, the most representative model for human CLL, into Th17 phenotype, employing a protocol of T-cell activation through the inducible co-stimulator (ICOS) alongside a polarizing cytokine mixture. We demonstrate augmented memory properties of in vitro-polarized IL-17-producing T cells, and preliminary in vivo persistence in leukemia-bearing mice. Our findings gain translational relevance through successful viral transduction of Eμ-TCL1 CD4+ T cells with a CD19-targeted CAR construct during in vitro Th17 polarization. Th17 CAR T cells exhibited remarkable persistence upon encountering antigen-expressing target cells. This study represents the first demonstration of the potential of in vitro-differentiated Th17 cells to enhance ACT efficacy in CLL.

Traditional Chinese medicine for acute myelocytic leukemia therapy: exploiting epigenetic targets.

Acute myeloid leukemia (AML) is a heterogeneous hematological malignancy with historically high mortality rates. The treatment strategies for AML is still internationally based on anthracyclines and cytarabine, which remained unchanged for decades. With the rapid advance on sequencing technology, molecular targets of leukemogenesis and disease progression related to epigenetics are constantly being discovered, which are important for the prognosis and treatment of AML. Traditional Chinese medicine (TCM) is characterized by novel pharmacological mechanisms, low toxicity and limited side effects. Several biologically active ingredients of TCM are effective against AML. This review focuses on bioactive compounds in TCM targeting epigenetic mechanisms to address the complexities and heterogeneity of AML.

Induction therapy for acute myeloid leukemia: still nothing beyond 7+3?

Induction therapy for acute myeloid leukemia: still nothing beyond 7+3?

Blinatumomab as frontline therapy for B-cell precursor acute lymphoblastic leukemia in a critically ill young adult: a case report

Blinatumomab as frontline therapy for B-cell precursor acute lymphoblastic leukemia in a critically ill young adult: a case report

Target Selection of CAR-T Therapy in Acute Myeloid Leukemia--Review

Chimeric antigen receptor (CAR) T cell therapy, one of the most promising tumor treatments, combines the targeted recognition of antigen and antibody with the killing effect of T cells. CAR-T has shown a strong therapeutic effect in lymphoid tumors and been applied in clinical practice. However, in the treatment of acute myeloid leukemia (AML), no effective and specific target like CD19 in lymphoid tumors has been found. Therefore, the key research direction is to try multiple probabilities and use optimization strategies to enhance efficacy and reduce toxicity. This review introduces the latest research progress of AML targets in CAR-T therapy in recent years, analyzes the related problems that need to be solved at present, and summarizes the optimization construction strategies mentioned in the research. Hope it can provide reference for related research and clinical application of related product.

Neurocognitive testing to predict ICANS post-CAR T.

e19003 Background: Since the approvals of chimeric antigen receptor T-cell (CAR T) therapy in acute lymphoblastic leukemia (ALL), non-Hodgkin lymphoma (NHL), and multiple myeloma (MM), it has been increasingly offered in centers nationwide. Immune effector cell-associated neurotoxicity syndrome (ICANS) poses a potentially fatal risk with CAR-T. Identifying patients at risk of having high grade ICANS is a thus a priority. Scoring systems such as the EASIX scores have accounted for disease and comorbidity factors but haven’t addressed neurocognitive function. The St. Louis University Mental Status (SLUMS) Exam and the Montreal Cognitive Assessment (MoCA) have not been examined for validity and reliability in this population, so we performed a retrospective review of CAR T patients at the University of Kansas Medical Center to identify if incidence or severity of ICANS could be correlated with neurocognitive testing performed in the pre-infusion period. Methods: Patients receiving CAR T targeting CD19 or BCMA between December 2017 and December 2023 were included. Neurocognitive testing was performed by trained onco-psychology, neurology, or hematology-oncology staff. The SLUMS exam is an 11 question exam scored on a 30 point scale to predict normal neurocognitive function (27-30 points), mild neurocognitive disorders (21-26 points), and dementia (0-20 points). The MoCA is an 11 question exam scored on a 30 point scale to predict normal cognition (26-30 points), mild cognitive impairment (18-25 points), moderate cognitive impairment (10-17 points), and severe cognitive impairment (<10 points). Incidence of ICANS and severity of ICANS were compared between patients who had any detected cognitive dysfunction and those who had none, as well as between the tiered result system unique to each test. Results: We included 360 patients in this analysis, (257 NHL, 84 MM and 19 ALL) leading to comparisons of 276 CD19-directed CAR T patients and 84 BCMA-directed CAR T patients. In CD19-directed patients, there were no differences in ICANS incidence according to the SLUMS scores. There was a significant increase in ICANS incidence for patients who had a positive MoCA exam, p=0.006. Additionally, ICANS incidence was correlated with more severe MoCA results, p=0.01. No differences in ICANS severity were observed using any neurocognitive test. In BCMA-directed patients, no differences in ICANS were observed using the SLUMS or MoCA. Conclusions: Our results suggest that while the SLUMS exam does not predict ICANS, the MoCA may independently predict incidence of ICANS. Patients with a higher score correlating with normal cognition are less likely to develop ICANS and may be appropriate for outpatient therapy. For those with lower scores correlating with more severe neurocognitive disorders, inpatient monitoring and early intervention will continue to be important.

Effect of CD22-directed CAR-T cells secreting anti-CD19 T cell engagers on control of leukemia progression compared to tandem anti-CD19/CD22 CAR-T cells.

2550 Background: Antigen-specific cancer immunotherapies, based on engineered T cells bearing chimeric antigen receptors (CARs) or the systemic administration of bispecific T cell-engagers (TCEs), have a significant impact on relapsed/refractory (R/R) B cell malignancies. However, a significant percentage of patients relapse following CAR-T or TCE therapy, with antigen loss accounting for up to one third of relapses/progressions. To avoid antigen loss after administration of single-targeted CAR-T cells and to minimize tumor escape, strategies targeting two antigens simultaneously have been developed and validated in both preclinical models and clinical trials. Nevertheless, despite lowering the risk of antigen loss, these strategies still have some limitations, mainly related to design and manufacturing challenges. Methods: In this context, we have generated the first dual-target strategy for hematological malignancies based on T cells bearing an anti-CD22 CAR and secreting an anti-CD19 T-cell engager antibody (CAR-STAb-T cells) and conducted a comprehensive preclinical study comparing its therapeutic potential with a previously validated anti-CD19/CD22 tandem CAR therapy (TanCAR-T) for B-cell acute lymphoblastic leukemia (B-ALL). Results: We have demonstrated in both short- and long-term assays, using contact and non-contact co-culture systems, that CAR-STAb-T cells efficiently redirect bystander T cells, resulting in enhanced cytotoxic activity compared to that exhibited by TanCAR-T cells at very low E:T ratios. In addition, CAR-STAb-T cells induce more potent and faster cytotoxic responses than TanCAR-T cells in both short- and long-term co-culture assays when reproducing antigen-downmodulated conditions in vitro. In vivo assays conducted in NSG mice transplanted with a B-ALL patient-derived xenograft (PDX), followed by intravenous injection of CAR-STAb-T or TanCAR-T cells under a T cell-limiting experimental setting, also showed that CAR-STAb-T cells maintained a tighter control of tumor progression than TanCAR-T cells in peripheral blood and bone marrow. Conclusions: In conclusion, we have demonstrated that the combination of a cell surface CAR and a soluble TCE recognizing different antigens may be advantageous over the use of conventional multi-targeted strategies based on cell surface-anchored receptors. Furthermore, we have proven that a small number of transduced CAR-STAb-T cells is sufficient to redirect non-transduced bystander T cells specifically and efficiently in the presence of leukemia cells, providing a significant advantage over current dual-targeted CAR-T cell therapies. CAR-STAb-T cells could therefore become an alternative to CAR-T therapies for the treatment of R/R B cell malignancies, especially in lymphodepleted patients with low T cell counts.

Chimeric antigen receptor T-cell therapy in childhood acute myeloid leukemia: how far are we from a clinical application?

Recurrent and/or refractory (R/R) pediatric acute myeloid leukemia (AML) remains a recalcitrant disease with poor outcomes. Cell therapy with genetically modified immune effector cells holds the promise to improve outcomes for R/R AML since it relies on cytotoxic mechanisms that are distinct from chemotherapeutic agents. While T cells expressing chimeric antigen receptors (CAR T cells) showed significant anti-AML activity in preclinical models, early phase clinical studies have demonstrated limited activity, irrespective of the targeted AML antigen. Lack of efficacy is most likely multifactorial, including: (i) a limited array of AML-specific targets and target antigen heterogeneity; (ii) the aggressive nature of R/R AML and heavy pretreatment of patients; (iii) T-cell product manufacturing, and (iv) limited expansion and persistence of the CAR T cells, which is in part driven by the immunosuppressive AML microenvironment. Here we review the results of early phase clinical studies with AML-specific CAR T cells, and avenues investigators are exploring to improve their effector function.

Infections during induction therapy of childhood acute lymphoblastic leukemia with MRC-11 protocol

Infections during induction therapy of childhood acute lymphoblastic leukemia with MRC-11 protocol

Disparities in frontline treatment and overall survival in the era of targeted tyrosine kinase inhibitor therapy for chronic myeloid leukemia: 2004-2021.

11187 Background: The treatment of chronic myeloid leukemia (CML) was revolutionized in 2001 with the introduction of the BCR::ABL tyrosine kinase inhibitor (TKI), imatinib. In 2006, dasatinib was approved, followed by nilotinib in 2007. Two other TKIs, bosutinib & ponatinib were approved in 2012, followed by the allosteric ABL myristoyl inhibitor asciminib in 2021, providing multiple options for patients (pts) who have refractory disease. In this study we examine how survival has improved in CML pts with the availability of multiple TKI’s and identify disadvantaged socioeconomic & demographic groups which continue to have disparate survival. Methods: The National Cancer Database was used to identify CML pts diagnosed (dx) from 2004-2021. Demographic, treatment, & overall survival (OS) were compared by era of TKI availability, with pts dx from 2004-2005 considered to be treated in the imatinib era, 2006-2011 for dasatinib & nilotinib, 2012-2020 with access to bosutinib & ponatinib, and 2021 for asciminib. Results: Of 44,993 CML pts identified, 55.8% were male & 82.5% were White, with median age of 58 years. The portion of pts who were untreated (due to contraindication or early death) decreased by each time period, from 17.8% in the imatinib era to only 7.8% in 2021. The rate of upfront transplant decreased from 2.5% from 2004-2005, to 0.8% in 2021. For dx 2004-2005 median OS was 11.5 yrs (95% CI 10.6-12.5). This increased to 13.6 yrs (CI 13.1-14.1), with age-adjusted hazard ratio (HR) of 0.86 (CI 0.81-0.91) for pts dx 2006-2011, with median OS unreached for 2012-2020, HR 0.67 (CI 0.63-0.71, p<0.001); referenced to 2004-2006. Survival at 1-, 5- & 10-yrs was improved for each subsequent time period of dx, with 5-yr OS of 65%, 71%, & 76%, respectively, p<0.001. On multivariate cox regression adjusted for yr of dx, features associated with reduced OS included age (HR 1.06 [95% CI 1.05-1.06], p<0.001 for each yr), Black race (HR 1.11 [95% CI 1.05-1.18], p<0.001), increased comorbidity index (HR 1.94 [95% CI 1.84-2.04], p<0.001 for index ≥2), uninsured (HR 2.20 [95% CI 2.01-2.41], p<0.001), or insured through Medicaid (HR 2.40 [95% CI 2.23-2.58], p<0.001). Conclusions: Survival for CML pts has significantly improved during the last 20 yrs with the availability of each additional TKI, likely related to increased treatment options for pts with resistance or intolerance. Additional TKI options, particularly approval of ponatinib for patients with T315I mutation, have a secondary benefit of decreasing the utilization of allogenic transplant. Though survival has improved for all pts, pts from traditionally underserved populations, including pts who are underinsured or from racial minority groups, have reduced OS. Continued advances in treatment & efforts to improve access to care for underserved populations is vital to achieve equitable survival outcomes in CML.

Naked antibodies and antibody-drug conjugates: targeted therapy for childhood acute lymphoblastic leukemia.

The treatment of childhood acute lymphoblastic leukemia (ALL) has reached overall survival rates exceeding 90%. The present and future challenges are to cure the remainder of patients still dying from disease, and to reduce morbidity and mortality in those who can be cured with standard-of-care chemotherapy by replacing toxic chemotherapy elements while retaining cure rates. With the novel therapeutic options introduced in the last years, including immunotherapies and targeted antibodies, the treatment of ALL is undergoing major changes. For B-cell precursor ALL, blinatumomab, an anti-CD19 bispecific antibody, has established its role in the consolidation treatment for both high- and standard-risk first relapse of ALL, in the presence of bone marrow involvement, and may also have an impact on the outcome of high-risk subsets such as infant ALL and Philadelphia chromosome-positive ALL. Inotuzumab ozogamicin, an anti-CD22 drug conjugated antibody, has demonstrated high efficacy in inducing complete remission in relapsed ALL, even in the presence of high tumor burden, but randomized phase III trials are still ongoing. For T-ALL the role of CD38-directed treatment, such as daratumumab, is gaining interest, but randomized data are needed to assess its specific benefit. These antibodies are currently being tested in patients with newly diagnosed ALL and may lead to major changes in the present paradigm of treatment of pediatric ALL. Unlike the past, lessons may be learned from innovations in adult ALL, in which more drastic changes are piloted that may need to be translated to pediatrics.

Clinical practice guidelines for adolescent and young adult cancer: A literature review.

e13727 Background: Cancers among adolescents and young adults (AYA, aged 15-39) are rising in incidence, yet formal guidelines for diagnosis, treatment, and management of AYA-specific cancers are not widely known or disseminated. Practice patterns vary widely, contributing to a lack of improvement in outcomes for this underserved population. Clinicians and health systems have reported a need for additional guidance in care delivery for AYAs. Methods: We conducted a comprehensive literature review to identify clinical practice guidelines for cancer care delivery specific to AYAs published in PubMed or MEDLINE since 2010. MeSH and other key words were applied, using a search strategy guided by a health science librarian (EM). 795 papers were identified, with 690 excluded based on title and abstract review. 105 papers underwent full text review, and 64 papers underwent complete data extraction. Using Covidence software, two team members independently reviewed articles at the data extraction phase, with disagreements resolved through discussion. Results: We identified 22 papers that met our inclusion criteria as clinical practice guidelines specific to AYA cancer care. Clinical focus included breast cancer (4), sarcoma (4), brain tumors (2), gynecologic malignancies (2), acute lymphoblastic leukemia (1), colorectal cancer (1), NUT carcinoma (1), and proton therapy (1). Six papers covered general principles of caring for AYAs, regardless of cancer diagnosis. Key themes across guidelines included the importance of fertility preservation and psychosocial support, multidisciplinary care provided at specialized centers, and consideration of long-term toxicities of treatment. Conclusions: Clinical practice guidelines exist to inform clinicians and health systems on best practices for caring for AYAs with cancer, a growing and underserved population. Further dissemination of these guidelines may assist with improving outcomes. Comprehensive summary of these and other AYA specific guidelines is forthcoming and may serve as a useful clinical reference. [Table: see text]

Evaluation of lipopolymer as therapeutic siRNA delivery agents in non-malignant and malignant primary cells.

e15189 Background: Targeting leukemia-driving oncogenes via short interfering RNA (siRNA) offers an alternative approach to leukemia treatment that can overcome the limitations of current therapies. Low molecular weight polyethyleneimine grafted with lipids (lipopolymers) have emerged as promising carriers for siRNA delivery to leukemia cells. Lipopolymers harboring select lipids were recently shown to downregulate target oncogene leading to significant anti-leukemic activity in both in vitro and in vivo cell line-based leukemia models. The goal of this study was to evaluate these lipopolymers in (i) PBMCs obtained from healthy donors to determine the potential impact on non-malignant cells, and (ii) primary leukemia patient cells to assess therapeutic efficacy. Methods: Target gene levels were determined by RT-qPCR and the effect of treatment on progenitor cells was assessed by measuring changes in colony forming ability. Results: At day 1 post-treatment, no changes in FLT3 mRNA levels were observed in all 6 PBMC samples with the 2 candidate lipopolymers (LeuFectB and LeuFectC) tested. Among 11 PBMC samples evaluated at day 2, only one sample showed a significant reduction in oncogene transcript levels on treatment with LeuFectB. The impact of lipopolymer/siRNA complex treatment on progenitor cells in the PBMC population was then assessed. Of the 7 PBMC samples tested, significant reduction in colony numbers was observed in one sample with LeuFectB and two samples with LeuFectC. On an average, the lipopolymer/siRNA complexes were well tolerated by normal healthy cells as changes observed in oncogene expression and colony forming ability were not consistent across the whole pool. Primary acute lymphoblastic leukemia (ALL) patient cells treated with complexes targeting STAT5A showed marked reduction in STAT5A transcript levels in 4 out of 7 samples with both the lipopolymers tested. The subsequent impact of STAT5A downregulation on the clonogenicity of leukemia stem cells was observed in the significant decrease in colony numbers seen in 3 samples (out of 8) with LeuFects. Additionally, combined downregulation of STAT5A and BCR-ABL genes in BCR-ABL+ ALL patient samples led to a notable decrease in cell proliferation and viability. Moreover,2 out of 3 acute myeloid leukemia (AML) patient samples harboring the FLT3-ITD mutation showed significant retardation in their colony forming ability on treatment with FLT3-targeting siRNA complexes. Collectively, the ALL and AML primary samples demonstrated promising preliminary results, suggesting a therapeutic effect on the stem cell population which is critical for mitigating relapse or prolonging remission. Conclusions: These findings provide further proof-of-concept for clinical translation of lipopolymer mediated siRNA therapy of leukemia, showing relative safety and selectivity of these lipopolymer/siRNA complexes.

The Safety of Novel Therapies in Chronic Lymphocytic Leukemia in the Era of Intermittent Fasting: A Pharmacology-Based Review.

Intermittent fasting (IF) has recently gained popularity due to its emerging benefits in reducing weight and improving metabolic health. Concurrently, novel agents (NAs) like venetoclax and Bruton tyrosine kinase inhibitors (BTKIs) have revolutionized the treatment of chronic lymphocytic leukemia (CLL). Unfortunately, it is unclear whether the associated risks of tumor lysis syndrome (TLS) and gastrointestinal bleeding (GIB) are increased in IF practitioners receiving NAs. This review explored the literature available on the permissibility of IF in CLL patients undergoing treatment with first-line NAs (FLNAs). Literature was scoped to identify IF patterns and the available data on TLS and GIB risks associated with food and fluid intake in CLL patients receiving FLNAs. Although current evidence is insufficient to recommend IF in this population, it may be possible for patients on venetoclax to conservatively practice fluid-liberal IF, provided that adequate hydration and the consistent administration of food are achieved. In contrast, considering the significant risk of TLS and the pharmacokinetics of venetoclax, patients should be discouraged from practicing fluid-restricted IF, especially during the ramp-up phase. Moreover, patients on BTKIs ought to refrain from IF due to the possible risk of GIB until further data are available. Further research is needed to provide conclusive recommendations.

Advancements and Future Prospects in Molecular Targeted and siRNA Therapies for Chronic Myeloid Leukemia.

Chronic myeloid leukemia (CML) is an oncological myeloproliferative disorder that accounts for 15 to 20% of all adult leukemia cases. The molecular basis of this disease lies in the formation of a chimeric oncogene BCR-ABL1. The protein product of this gene, p210 BCR-ABL1, exhibits abnormally high constitutive tyrosine kinase activity. Over recent decades, several targeted tyrosine kinase inhibitors (TKIs) directed against BCR-ABL1 have been developed and introduced into clinical practice. These inhibitors suppress BCR-ABL1 activity through various mechanisms. Furthermore, the advent of RNA interference technology has enabled the highly specific inhibition of BCR-ABL1 transcript expression using small interfering RNA (siRNA). This experimental evidence opens avenues for the development of a novel therapeutic strategy for CML, termed siRNA therapy. The review delves into molecular genetic mechanisms underlying the pathogenesis of CML, challenges in CML therapy, potential molecular targets for drug development, and the latest results from the application of siRNAs in in vitro and in vivo CML models.