DigitalCommons@The Texas Medical Center
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Molecular Characterization and Predictors of Relapse in Patients With Ph + All After Frontline Ponatinib and Blinatumomab
No full textBackground: Several studies have suggested that chemotherapy-free regimens consisting of blinatumomab and a BCR::ABL1 tyrosine kinase inhibitor are highly effective in Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph + ALL). However, the clinical and molecular characteristics that predict for relapse with these chemotherapy-free regimens are largely unknown.
Methods: We conducted a prospective phase II clinical trial of the combination of blinatumomab and ponatinib in 76 patients with newly diagnosed Ph + ALL. Patients received 12-15 doses of intrathecal chemotherapy as central nervous systemic (CNS) prophylaxis. The patterns of relapse and the clinical and molecular predictors of relapse were analyzed.
Results: With a median follow-up of 29 months, the estimated 3-year event-free survival rate was 78% and the 3-year overall survival rate was 88%. Ten patients (13%) relapsed, with a median time to relapse of 18 months (range, 8-24 months). Six relapses occurred only in extramedullary sites (CNS, n = 5; peritoneum and lymph nodes, n = 1). CD19 expression remained high at relapse in all patients. On univariate analysis, factors associated with an increased risk of relapse were: white blood cell (WBC) ≥ 70 × 109/L at diagnosis (sHR 8.86 [95% CI 2.33-33.70]; P = 0.001), CNS involvement at diagnosis (sHR 6.87 [95% CI 1.54-30.68]; P = 0.01), and VPREB1 deletion (sHR 4.06 [95% CI 1.05-15.76]; P = 0.04). WBC ≥ 70 × 109/L was present in 22% of the cohort and was associated with a 53% cumulative incidence of relapse (CIR), as compared with a CIR rate of 6% for patients with WBC \u3c 70 × 109/L. Neither IKZF1plus genotype, BCR::ABL1 transcript type, nor measurable residual disease kinetics by next-generation sequencing for IG/TR rearrangements significantly impacted the risk of relapse. High WBC at diagnosis was the only variable significantly associated with relapse on multivariate analysis (sHR 16.29 [95% CI 2.35-113.00; P = 0.005).
Conclusions: WBC ≥ 70 × 109/L is a high-risk feature in patients with Ph + ALL receiving frontline blinatumomab and ponatinib and may supersede the prognostic importance of baseline molecular features. Alternative frontline treatment strategies may be needed for these patients to reduce the risk of relapse and improve long-term outcomes.
Trial registration: ClinicalTrials.gov (NCT03263572)
β-Catenin Drives the FOXC2-Mediated Epithelial-Mesenchymal Transition and Acquisition of Stem Cell Properties
No full textBackground: Aggressive forms of breast cancer, such as triple-negative breast cancer (TNBC), are associated with an increase in cancer cells that exhibit stem cell properties. The activation of the epithelial-mesenchymal transition (EMT) program, mediated by the transcription factor FOXC2, generates these stem-like cells. FOXC2 is linked to poor prognoses across various cancer types and is notably upregulated in TNBC, where it establishes and sustains these stem-like cells within the tumor population.
Methods: Here, we decode the pathways regulating FOXC2 activation using EMT-enriched cell line models. Stemness was assessed using mammosphere assays and mesenchymal markers by western blot. Expression correlations with clinical data was examined using the EMTome.
Results: We demonstrate that β-catenin serves as a critical mediator of mesenchymal and stemness characteristics through FOXC2 upregulation. By disrupting β-catenin, we find that FOXC2 expression, mesenchymal properties, and stemness are reduced; however, the introduction of exogenous FOXC2 expression in β-catenin deficient cells is enough to restore the mesenchymal and stemness phenotype. These findings support the idea that FOXC2 acts as the downstream regulator of β-catenin and influences both mesenchymal and stemness properties. Moreover, there is a positive correlation between the expression of β-catenin and FOXC2 in various cancer subtypes observed in clinical patient samples.
Conclusions: Our study clarifies the role of the β-catenin/FOXC2 signaling axis in maintaining stemness properties, suggesting potential targets for TNBC and other cancers driven by EMT-related mesenchymal and stemness characteristics
A Predictive Chromatin Architecture Nexus Regulates Transcription and DNA Damage Repair
No full textGenomes are blueprints of life essential for an organism\u27s survival, propagation, and evolutionary adaptation. Eukaryotic genomes comprise of DNA, core histones, and several other nonhistone proteins, packaged into chromatin in the tiny confines of nucleus. Chromatin structural organization restricts transcription factors to access DNA, permitting binding only after specific chromatin remodeling events. The fundamental processes in living cells, including transcription, replication, repair, and recombination, are thus regulated by chromatin structure through ATP-dependent remodeling, histone variant incorporation, and various covalent histone modifications including phosphorylation, acetylation, and ubiquitination. These modifications, particularly involving histone variant H2AX, furthermore play crucial roles in DNA damage responses by enabling repair protein\u27s access to damaged DNA. Chromatin also stabilizes the genome by regulating DNA repair mechanisms while suppressing damage from endogenous and exogenous sources. Environmental factors such as ionizing radiations induce DNA damage, and if repair is compromised, can lead to chromosomal abnormalities and gene amplifications as observed in several tumor types. Consequently, chromatin architecture controls the genome fidelity and activity: it orchestrates correct gene expression, genomic integrity, DNA repair, transcription, replication, and recombination. This review considers connecting chromatin organization to functional outcomes impacting transcription, DNA repair and genomic integrity as an emerging grand challenge for predictive molecular cell biology
Galectin-1 Inhibition as a Strategy for Malignant Peripheral Nerve Sheath Tumor Treatment
No full textNeurofibromatosis type 1 (NF1) is an inherited disorder that predisposes individuals to malignant peripheral nerve sheath tumors (MPNSTs), a highly aggressive sarcoma with limited treatment options and poor prognosis. This study explores the potential of targeting the interaction between Galectin-1 and Ras as a novel therapeutic strategy for MPNSTs. Through molecular docking, we identified critical residues involved in the Galectin-1 and H-Ras interaction. We developed LLS30, a compound designed to target this Ras-binding pocket on Galectin-1, and tested its efficacy. LLS30 effectively disrupted the Galectin-1/Ras interaction, causing Ras delocalization from the plasma membrane and inhibiting Ras signaling. In vitro experiments showed that LLS30 significantly decreased MPNST cell proliferation and induced apoptosis. In vivo, LLS30 demonstrated potent anti-tumor effects, reducing tumor size, inhibiting metastasis, and extending survival in animal models. Transcriptome analysis further revealed the downregulation of KRAS signaling and inhibition of pathways associated with epithelial-mesenchymal transition. These findings suggest that targeting Galectin-1 with LLS30 offers therapeutic potential for MPNSTs and could be beneficial for other cancers driven by Galectin-1 and Ras signaling
Phase I Trial of TTI-101, a First-in-Class Oral Inhibitor of STAT3, in Patients with Advanced Solid Tumors
No full textPurpose: Signal transducer and activator of transcription 3 is a transcription factor that is essential for the survival and immune sequestration of cancer cells. We conducted a phase I study of TTI-101, a first-in-class, selective small-molecule inhibitor of signal transducer and activator of transcription 3, in patients with advanced metastatic cancer.
Patients and methods: Patients were treated with TTI-101 orally twice daily in 28-day cycles at four dose levels (DL): 3.2 (DL1), 6.4 (DL2), 12.8 (DL3), and 25.6 (DL4) mg/kg/day ( 3+3 design). Three TTI-101 formulations were used in a stepwise manner (NCT03195699).
Results: Sixty-four patients were treated (median age, 63 years; male sex, 52%; median number of prior therapies, 3). No dose-limiting toxicities or fatal treatment-related adverse events (TRAE) were observed. Diarrhea (mostly grade 1/2) was the only TRAE observed in ≥30% of subjects. Five patients experienced grade 3 TRAEs that resolved. TTI-101 showed linear pharmacokinetics from DL1 to DL3, with the pharmacokinetics plateauing at DL3. The recommended phase II dose is 12.8 mg/kg/day (DL3). Of the 41 patients who were evaluable for response, five (12%) had confirmed partial responses (cPR) and 17 (41%) had stable disease. Three (18%) of the 17 patients with hepatocellular carcinoma had a cPR (median time to treatment failure, 10.6 months). Two other cPRs were noted in one patient with ovarian cancer and one patient with gastric cancer.
Conclusions: TTI-101 was well tolerated. cPRs were observed across tumor types. The antitumor activity of TTI-101 monotherapy in patients with advanced, metastatic solid tumors is promising. A phase II study of TTI-101 in hepatocellular carcinoma is currently underway
IDH Status Dictates oHSV Mediated Metabolic Reprogramming Affecting Anti-tumor Immunity
No full textIdentification of isocitrate dehydrogenase (IDH) mutations has uncovered the crucial role of metabolism in gliomagenesis. Oncolytic herpes virus (oHSV) initiates direct tumor debulking by tumor lysis and activates anti-tumor immunity, however, little is known about the role of glioma metabolism in determining oHSV efficacy. Here we identify that oHSV rewires central carbon metabolism increasing glucose utilization towards oxidative phosphorylation and shuttling glutamine towards reductive carboxylation in IDH wildtype glioma. The switch in metabolism results in increased lipid synthesis and cellular ROS. PKC induces ACSL4 in oHSV treated cells leading to lipid peroxidation and ferroptosis. Ferroptosis is critical to launch an anti-tumor immune response which is important for viral efficacy. Mutant IDH (IDHR132H) gliomas are incapable of reductive carboxylation and hence ferroptosis. Pharmacological blockade of IDHR132H induces ferroptosis and anti-tumor immunity. This study provides a rationale to use an IDHR132H inhibitor to treat high grade IDH-mutant glioma patients undergoing oHSV treatment
Ubiquitin-Conjugating Enzyme UBE2N Modulates Proteostasis in Immunoproteasome-Positive Acute Myeloid Leukemia
No full textAltered protein homeostasis through proteasomal degradation of ubiquitinated proteins is a hallmark of many cancers. Ubiquitination, coordinated by E1, E2, and E3 enzymes, involves up to 40 E2-conjugating enzymes in humans to specify substrates and ubiquitin linkages. In a screen for E2 dependencies in acute myeloid leukemia (AML), ubiquitin conjugating enzyme E2 N (UBE2N) emerged as the top candidate. To investigate UBE2N\u27s role in AML, we characterized an enzymatically defective mouse model of UBE2N, revealing UBE2N\u27s requirement in AML without an impact on normal hematopoiesis. Unlike other E2s, which mediate lysine-48 (K48) polyubiquitination and degradation of proteins, UBE2N primarily synthesizes K63-linked chains, stabilizing or altering protein function. Proteomic analyses and a whole-genome CRISPR-activation screen in pharmacologically and genetically UBE2N-inhibited AML cells unveiled a network of UBE2N-regulated proteins, many of which are implicated in cancer. UBE2N inhibition reduced their protein levels, leading to increased K48-linked ubiquitination and degradation through the immunoproteasome and revealing UBE2N activity is enriched in immunoproteasome-positive AML. Furthermore, an interactome screen identified tripartite motif-containing protein 21 (TRIM21) as the E3 ligase partnering with activated UBE2N in AML to modulate UBE2N-dependent proteostasis. In conclusion, UBE2N maintains proteostasis in AML by stabilizing target proteins through K63-linked ubiquitination and prevention of K48 ubiquitin-mediated degradation by the immunoproteasome. Thus, inhibition of UBE2N catalytic function suppresses leukemic cells through selective degradation of critical proteins in immunoproteasome-positive AML
The Clinical Utility of a Next-Generation Sequencing-Based Approach to Detecting Circulating HPV DNA in Patients with Advanced Anal Cancer
No full textBackground: To extend the practicality of liquid biopsy beyond the historical HPV circulating tumor DNA (ctDNA) assays, we evaluated the clinical relevance of a novel next-generation sequencing HPV ctDNA assay in patients with locally advanced and metastatic squamous cell cancer of the anal canal (mSCCA).
Methods: ctDNA isolated from the plasma of patients with mSCCA was sequenced using a 1.4 Mb hybrid-capture target-enrichment panel covering the whole genome sequences of all 193 HPV types. The HPV type, copy number (CN), and integration sites were determined using a bioinformatic pipeline.
Results: A total of 77 plasma samples from 28 patients with HPV-related SCCA were retrospectively analyzed. HPV ctDNA was detected in 26 cases (93%) (including uncommon subtypes). The median HPV CN was higher in metastatic versus locally recurrent/unresectable SCCA (p = 0.043). Changes in the HPV CN were concordant with the radiographic response (p = 0.027). An integration event was detected in 23 patients (82%), with presumed episomal HPV DNA present in the remaining patients. Higher HPV integration (a mean of ≥1 integration across samples) was associated with a worse overall survival from the start of immunotherapy (13.6 months versus 36.0 months; p = 0.003).
Conclusions: Using HPV-informed next-generation sequencing of the ctDNA, we found changes in the HPV CN correlated with the treatment response and that HPV integration detected in the ctDNA is an unfavorable prognostic biomarker
Association of SIRT6 Expression With Risk of Pneumonitis Induced by Radiotherapy in Cancer Patients
No full textThoracic tumours represent a significant proportion of malignant cancers. While radiotherapy (RT) improves prognosis, it can also lead to side effects such as radiation-induced pneumonitis (RP). Since SIRT6 is involved in DNA repair, energy metabolism and inflammation, this study aims to investigate the expression of SIRT6 in lymphocytes as a potential biomarker and therapeutic target for RP. This study included 170 patients diagnosed with thoracic tumours, all of whom underwent thoracic RT. RP was evaluated and classified as severe RP (SRP) and lower as non-severe RP (NSRP). Analyses were performed using SPSS version 26.0 and the R. Among 170 patients in this study, 124 developed NSRP, and 46 experienced SRP. The univariate analysis showed that SIRT6 expression (cOR, 0.33, 95%CI, 0.18-0.97 before RT and 0.31, 0.19-0.98 after RT), clinical factors, dosimetric parameters and haematological/serological parameters were associated with SRP before and after RT. Our multivariable logistic regression showed that SIRT6 expression was significantly associated with risk of SRP before (aOR, 0.32, 95%CI, 0.15-0.96) and after RT (aOR, 0.32, 95%CI, 0.18-0.99) after adjustment with other confounders. Moreover, the receiver operating characteristic curve analysis revealed that the combined multivariable model exhibited superior predictive capability compared to any single predictor (overall AUC, 0.93, 95%CI, 0.90-0.97 before RT and AUC, 0.91, 95%CI, 0.87-0.96 after RT). The expression of SIRT6 alone or in combination with other risk factors was associated with an increased risk of SRP, suggesting a novel approach for the prevention and treatment of radiation pneumonitis in clinical practice
Targeted Normoxemia and Supplemental Oxygen-Free Days in Critically Injured Adults: A Stepped-Wedge Cluster Randomized Clinical Trial
No full textImportance: Supplemental oxygen is fundamental to caring for critically injured adults but can expose them to excess inspired oxygen.
Objective: To determine the safety and effectiveness of targeting normoxemia in critically ill trauma patients.
Design, setting, and participants: This multicenter, stepped-wedge, cluster randomized clinical trial compared targeted normoxemia (defined as a peripheral oxygen saturation [Spo2] of 90% to 96%) with usual care among adult trauma patients admitted to an intensive care unit (ICU) at 8 level I trauma centers across the US. These trauma centers were randomized at 3-month intervals when they crossed over from usual care to targeting normoxemia. Eligible patients were enrolled between July 15, 2020, and November 14, 2022. All statistical analyses were performed from April 2023 to November 2024 according to intention-to-treat approach.
Intervention: In the usual care group, supplemental oxygen was determined by treating clinicians. In the targeted normoxemia group, a multimodal educational and informatics intervention encouraged decreasing the supplemental oxygen administered whenever Spo2 exceeded 96%.
Main outcomes and measures: The primary outcome was supplemental oxygen-free days (SOFDs), defined as the number of days alive and not receiving supplemental oxygen through day 28. Safety outcomes included hypoxemia (defined as Spo2 \u3c 88%) during the ICU admission, in-hospital mortality, and adverse events.
Results: A total of 12 487 patients were enrolled (mean [SD] age, 51.7 [21.1] years; 8799 males [70.5%]; mean [SD] Injury Severity Score, 19.6 [12.0]). The proportion of ICU time spent in normoxemia increased from 56.2% in the usual care group to 71.6% in the targeted normoxemia group. Hyperoxemia (defined as Spo2 \u3e96%) decreased from 42.4% in the usual care group to 26.7% in the targeted normoxemia group, and hypoxemia was similar between groups (1.1% vs 1.1%). The raw mean (SD) number of SOFDs was 19.6 (10.3) days for the targeted normoxemia group and 17.5 (10.4) days for the usual care group (adjusted mean difference [AMD], 0.32 [95% CI, -0.37 to 1.00] days; P = .30). Among patients not receiving mechanical ventilation at ICU admission, mean SOFDs were greater in the targeted normoxemia group than in the usual care group (22.6 [8.30] days vs 20.6 [8.86] days; AMD, 0.75; 95% CI, 0.00-1.50 days). The mean (SD) time for weaning to room air was 1.6 (3.2) days for the targeted normoxemia group and 2.7 (4.0) days for the usual care group (adjusted hazard ratio [AHR], 1.23; 95% CI, 1.13-1.33 days). In-hospital mortality to day 90 occurred in 563 patients (9.9%) in the targeted normoxemia and 732 patients (10.7%) in the usual care group (AHR, 1.05; 95% CI, 0.83-1.33). No adverse events were reported in either group.
Conclusions and relevance: This randomized clinical trial showed that targeting normoxemia did not increase the number of SOFDs but safely reduced supplemental oxygen use among critically ill trauma patients.
Trial registration: ClinicalTrials.gov Identifier: NCT04534959