Experimental Hematology & Oncology最新文献

Chimeric antigen receptor T cell (CAR-T) is the main salvage therapy for relapsed or refractory large B-cell lymphoma (r/r LBCL). However, over 50% of patients relapse after CAR-T therapy. In this work, we transduced the CAR gene into hematopoietic stem cells (HSCs) using a lentiviral vector. Chimeric antigen receptor-modified HSC (CAR-HSCs) were transplanted into mice after lethal irradiation. CAR gene transduction did not compromise the ability of HSCs to expand, self-renew, or reconstitute. CAR was expressed on T cells, natural killer cells, B cells, monocytes, and neutrophils in the peripheral blood. CAR-HSCs transplantation significantly reduced CD19⁺ tumor burden and prolonged the survival of mice with preclinical tumor without severe toxicity. CAR-HSCs also differentiated into different CAR-expressing immune cells that reshaped the tumor microenvironment by increasing the proportion of antitumor cells (like CD8⁺ T cells) and the antitumor response, and by decreasing immunosuppressive cells, such as tumor-associated macrophage subtype 2. This study demonstrated a preclinical proof-of-principle for CAR-HSCs therapy in r/r LBCL, suggesting an opportunity for its clinical translation.

Background: Triple-negative breast cancer (TNBC) is notorious for its poor prognosis, high metastatic rates, and resistance to chemotherapy. We sought to investigate the anticancer effects of pitavastatin (PITA), a promising candidate for drug repurposing due to its potent inhibition of myeloid cell leukemia 1 (Mcl-1).

Methods: The impact of PITA on TNBC cells was assessed in vitro by examining cell viability, apoptosis, mitochondrial function, and effects on cancer stem cell (CSC) properties. The interaction between PITA and Mcl-1 was explored using molecular docking simulations and surface plasmon resonance (SPR) assays. In vivo studies using CSC-enriched allografts and a paclitaxel-resistant metastatic model were conducted to understand translational relevance.

Results: PITA's direct inhibition of Mcl-1 enabled potent suppression of TNBC cells by selectively enhancing mitochondrial ROS production, reducing mitochondrial membrane potential, and depleting ATP content, triggering caspase-mediated apoptosis. PITA effectively targeted CSC-like subpopulations, marked by high ALDH1 activity and the CD44^high/CD24^low phenotype. By downregulating p-glycoprotein and Mcl-1/Bcl-2 signaling, PITA was also effective at counteracting paclitaxel resistance, and disrupted AKT/STAT3 survival pathways. PITA significantly inhibited the growth of TNBC patient-derived tumor organoids (PDTOs). Furthermore, its combination with paclitaxel exhibited a synergistic effect on TNBC organoid growth inhibition. In vivo, PITA exhibited potent anti-tumorigenic and anti-metastatic effects, significantly reducing tumor growth and lung metastasis in TNBC allograft models without overt toxicity.

Conclusion: PITA's inhibition of Mcl-1 represents a novel mechanism to address treatment-refractory metastatic TNBC. Further assessment of PITA's therapeutic potential is warranted.

MLL (KMT2A)-rearranged leukemia (MLL-r) is a highly aggressive hematologic malignancy driven by transcriptional dysregulation. Here, we identify EYA family phosphatase activity, particularly EYA1 and EYA3, as key vulnerabilities in MLL-r leukemia. The small molecule benzbromarone (BBR) selectively reduced viability in MLL-r and EYA-expressing MLL-nonrearranged (MLL-nr) leukemia cells. Inhibition of EYA PTP activity increased global RNA Pol II CTD Tyr1 phosphorylation, linking aberrant EYA PTP activity in responsive leukemia cells to transcriptional dysregulation. In vivo, BBR treatment significantly prolonged survival and reduced leukemia burden without overt toxicity. Furthermore, BBR synergized with the menin-MLL inhibitor VTP50469 and showed additive effects with the DOT1L inhibitor EPZ5676, the latter of which restored BBR sensitivity in previously BBR-unresponsive cells. These findings establish EYA PTP activity as a therapeutic target in MLL-r leukemia, support the use of EYA expression for identifying patients likely to benefit from BBR treatment, and highlight the potential of BBR-based combinations to improve response in this high-risk leukemia subtype.

KMT2A-altered acute myeloid leukemia (AML) comprises rearrangements (KMT2A-r), partial tandem duplications (KMT2A-PTD), and dual alterations (KMT2A-r/PTD). In this study of 125 patients, these subgroups exhibited distinct molecular profiles: KMT2A-r cases were enriched in RAS pathway mutations, whereas KMT2A-PTD showed a higher burden of epigenetic alterations. Although overall survival (OS) and event-free survival (EFS) did not differ significantly between subgroups, prognosis was strongly influenced by fusion partners. MLLT3/ELL-rearranged cases showed superior outcomes, but concurrent KMT2A-PTD abrogated this survival advantage, AFDN and other fusions showed poor outcomes. We therefore propose a revised three-tier risk model integrating fusion partner and PTD status, which significantly stratified patient outcomes. The intermediate-risk group (MLLT3/ELL without PTD) had a 3-year OS of 78.1%, compared to 50.5% in the high-risk group (all PTD), and 34.9% in the very high-risk group (other KMT2A-r) (P = 0.044). For EFS, the rates were 71.0%, 40.1%, and 24.9%, respectively (P = 0.003). Allogeneic hematopoietic cell transplantation significantly improved survival, with 3-year OS rates of 75.2% in transplant recipients versus 22.5% in non-transplanted patients (P < 0.001), particularly in high-risk groups and when performed in first complete remission. These findings support the use of molecularly guided, risk-adapted therapy in KMT2A-altered AML.

Vaccination with tumor-(neo) antigen plus adjuvant is emerging as a promising cancer-therapy. However, as different adjuvants induce distinct immune cell and antibody (Ab) responses, selecting the right adjuvants remains challenging. Here, we evaluated the following vaccine adjuvants to promote protection against tumor-growth in mice and correlated IgG subclass and Fc N-glycosylation responses: Alum; the toll-like receptor activators Poly(I:C) and MPLA; Alum-Poly(I:C); and the more inflammatory water-in-oil adjuvants Montanide, IFA, CFA, and M.tb.-enriched (e)CFA. While Alum and Montanide failed to protect, MPLA and IFA tended to protect, and Poly(I:C), Alum-Poly(I:C), CFA, and eCFA significantly protected against tumor-growth. Across all adjuvants, tumor-protection correlated with the induction of highly activating IgG2(c/b) Abs and afucosylated (F0) IgG1 Abs, the latter showing up to 5% abundance. While all adjuvants transiently induced IgG1 F0 following initial immunization, Poly(I:C)- and eCFA-induced memory responses also generated IgG1 F0 after repeated antigen-exposure without adjuvants. Additionally, Poly(I:C)-induced tumor-protection was associated with high IgG2c/IgG1 ratios, high levels of IgG galactosylation and sialylation, and IFNγ-producing CD8 + Tc1-cells. Conversely, Ova-eCFA-induced tumor-protection was additionally associated with high levels of IgG across all subclasses, but low levels of galactosylation and sialylation, and CD8 + Tc17- and CD4 + Th17-cells. Accordingly, tumor protecting adjuvants may induce common but also different protecting programs. A tumor-antigen-specific IgG2a monoclonal (m)Ab protected against tumor-growth in both its de-galactosylated and galactosylated plus sialylated forms, suggesting common and possibly distinct protective mechanisms. Tumor-protection via serum transfer from Poly(I:C)-immunized mice depended more on NK-cells, whereas eCFA-induced and non-sialylated/non-galactosylated mAbs promoted neutrophil activation. These findings may help to improve tumor vaccination protocols.

Brain metastases (BM) from non-small cell lung cancer (NSCLC) represent a significant clinical challenge, characterized by poor prognosis and treatment resistance. While cancer-associated fibroblasts (CAFs) are recognized as crucial components of the BM tumor microenvironment (TME), their mechanistic contributions to disease progression and therapeutic resistance remain poorly understood. In this study, we demonstrated that patient-derived BM-CAFs significantly enhanced NSCLC cell proliferation, migration, invasion and therapeutic resistance in vitro. Mechanistically, BM-CAFs promoted epithelial-mesenchymal transition (EMT) and cancer stem cell (CSC) phenotypes through upregulation of key transcription factors. In-vivo experiments showed that co-injection of NSCLC cells with BM-CAFs accelerated tumor growth and enhanced cisplatin resistance. Molecular analysis revealed these effects were mediated through distinct mechanisms whereby IL26 activated the JAK-STAT3 pathway, while CX3CL1 activated both JAK-STAT3 and AKT-mTOR pathways. Importantly, neutralizing antibodies against IL26 and CX3CL1 effectively suppressed their respective signaling pathways and reversed EMT and CSC characteristics. In summary, our findings establish the IL26 and CX3CL1 signaling as a critical mediator of BM-CAF-induced tumor progression and therapy resistance in NSCLC BM, suggesting a potential therapeutic strategy for this challenging disease.

Tumor-infiltrating lymphocyte (TIL) therapy, a highly promising form of adoptive cell therapy (ACT), has demonstrated success in treating advanced melanoma. Notably, innovative TIL-based monotherapies and combination regimens have provided durable clinical responses and survival benefits for patients with various solid tumors. This article summarizes recent advances in TIL therapy for solid tumors presented at the 2025 ASCO Annual Meeting, highlighting monotherapies such as Lifileucel, LM103, OBX-115, GT101, GT300, GT201, and HS-IT101, as well as combination strategies with the oncolytic adenovirus TILT-123 or pembrolizumab.

Venous thromboembolism (VTE) remains a significant cause of morbidity and mortality, particularly among individuals with inherited thrombophilia. Despite the widespread use of thrombophilia testing, its clinical value is often questioned due to inconsistent guidelines and limited prospective evidence. Traditional testing panels target only a narrow set of common variants-such as Factor V Leiden and Prothrombin G20210A-and may miss rare, complex, or combined mutations, especially in high-risk patients, including pediatric populations and those with unprovoked events or atypical presentations. This correspondence aims to re-evaluate the clinical role of thrombophilia testing in light of next-generation sequencing (NGS), a technology that offers a broader, more precise assessment of heritable thrombotic risk. We discuss how NGS improves variant detection, enhances risk stratification, and supports a precision medicine framework-particularly in clinical scenarios where standard algorithms fail. By integrating emerging evidence and real-world applications, we advocate for an updated, individualized approach to genetic testing in VTE care.

Background: Zevorcabtagene autoleucel (zevor-cel) is a fully human autologous CAR T-cell therapy targeting B-cell maturation antigen approved in China since 2024 for patients with relapsed/refractory multiple myeloma (RRMM).

Methods: LUMMICAR STUDY 1 is a phase 2, single-arm study conducted across 23 centers in China. RRMM patients aged ≥ 18 to ≤ 75 years with measurable disease who had received ≥ 3 prior lines of therapy, with adequate organ function and bone marrow reserve, with an Eastern Cooperative Oncology Group (ECOG) score of 0-1, were eligible. Patients previously treated with any CAR T-cell therapy, or any BCMA-directed therapy were ineligible. The primary endpoint was objective response rate (ORR) determined by an Independent Review Committee. The secondary endpoints included ORR determined by investigator, additional efficacy outcomes including complete response (CR)/ stringent complete response (sCR) rate, duration of response (DOR), minimal residual disease negativity, safety outcomes including incidence and severity of adverse events, and pharmacokinetics of zevor-cel.

Results: Overall, 125 patients underwent apheresis, 105 patients received lymphodepletion, 102 patients (median age of 59.5 [range: 38, 75] years; 53.9% male and 46.1% female) received zevor-cel. The ORR was 92.2% (95% CI 85.13-96.55) with 70 patients (68.6%) achieving sCR and 3 (2.9%) achieving CR. At a median follow-up of 20.3 (interquartile range [IQR] 12.5, 23.8) months, 45 (44.1%) progression-free survival (PFS) events and 20 (19.6%) overall survival (OS) events were observed, the DOR, PFS and OS data were not mature. Cytokine release syndrome was reported in 92 (90.2%) patients, with grade 3 or 4 events in 7 (6.9%) patients. Immune effector cell associated neurotoxicity syndrome was reported in 2 patients at grade 1; no zevor-cel-related grade ≥ 3 neurotoxicity occurred.

Conclusion: Zevor-cel induces deep and durable responses in heavily pre-treated RRMM patients with a manageable safety profile.

In recent years, the Phosphoinositide-3-Kinase α (PI3Kα) signaling pathway has been increasingly recognized as a critical driver of tumorigenesis, particularly in breast cancer drug resistance and other solid tumors. Although conventional PI3Kα inhibitors (e.g., Alpelisib) have shown efficacy in extending progression-free survival in patients with PI3Kα-mutant breast cancer, their clinical application remains constrained by off-target toxicities, particularly hyperglycemia, which limits dosing and therapeutic feasibility. Building on recent preclinical findings, this study introduces BBO-10203, a first-in-class, orally bioavailable small-molecule inhibitor targeting the RAS-PI3Kα interaction. The compound is rationally designed to selectively and covalently bind to Cysteine 242 (Cys242) within the Rat Sarcoma (RAS)-Binding Domain (RBD) of PI3Kα, thereby effectively disrupting RAS-mediated PI3Kα activation. This unique mechanism confers potent in vivo antitumor activity while preserving insulin-regulated glucose metabolism, thereby mitigating metabolic adverse effects.