Kill Tumor Cells Research Articles

Effect of NIR-II on cancer nanocomposite vaccines for lymph node targeted delivery and enhanced immunotherapy.

e20506 Background: Cancervaccines have become one of the hot areas of research in recent years. However, different types of tumors and the tumor tissue itself are heterogeneous. Some cancervaccines contain a single epitope and have weak immunogenicity. The antigen-presenting cells cannot adequately absorb and present the antigen peptide contained in the vaccine. As a result, the body fails to elicit an effective immune response, which greatly limits the therapeutic effect of the cancervaccine. In situ cancervaccines composed of antigens and adjuvants are a promising cancer treatment modality; however, convenient manufacturing of vaccines in vivo and their efficient delivery to lymph nodes (LNs) remain a significant challenge. In this study, we outline a facile approach to simultaneously achieve in situ programming of vaccines via two synergistic nanomedicines to generate robust immune responses. Methods: We first prepared two synergistic nanocomposite systems: Gold nanorods, amphiphilic polymer polyphosphate mPEG- b-PHEP encapsulating the immune adjuvant R848, and nanoparticles doped with cationic liposomes DOTAP. Two nanomedicines were characterized and the efficacy of the nanovaccine was verified at the Cellular Experiments. At the animal level, the lymph node targeting of the nanoparticles was demonstrated through IVIS. We also constructed distant model and lung metastasis model to verify the nanovaccine's effect on enhancing systemic immunotherapy. Results: We used amphiphilic polymer polyphosphate mPEG- b-PHEP to encapsulate TLR7/8 agonist R848 to obtain VNPR848 nanoparticles. Gold nanorods (~ 100nm) can produce a strong photothermal effect mediated by NIR-II, killing tumor cells and releasing abundant antigens at the same time. The small size of VNPR848 (~ 30nm) is beneficial to the enrichment of lymph nodes. After capturing the antigens produced by photothermal, nanoparticles will be targeted and delivered to the tumor draining lymph nodes together with R848, and will be effectively absorbed by DC cells. This in situ tumor vaccine with the ability of targeted delivery of lymph nodes can trigger a strong anti-tumor immune response. This therapy can completely inhibit distant tumors in some mice and produce a long-term immune memory effect on NSCLC metastasis. Conclusions: We propose a simple personalized in situ cancervaccine strategy, which uses nanotechnology to remove tumors in situ and release antigens. Antigens and immune adjuvants are simultaneously delivered to the draining lymph nodes to initiate the antigen presentation function of DC cells, resulting in an anti-tumor immune response to inhibit tumor recurrence and metastasis. The nano-vaccine based on powerful therapeutic effect provides an attractive technology for in situ programming of personalized cancervaccine and an effective strategy for the development of cancervaccine.

Psilocybin, peyote, mescaline, and lysergic acid diethylamide (LSD) use in a nationally representative population by cancer history.

e22518 Background: Classic psychedelics (Peyote, Psilocybin, Mescaline, and LSD) are re-emerging in the oncology toolbox. Peyote is the oldest known psychedelic, yet underexplored in clinical research. Preclinical studies suggest its extract stimulates lymphocyte proliferation, kills tumor cells, and may regulate sleep. This study aims to estimate the prevalence of classic psychedelic use among a US-representative sample of adults with and without a history of cancer. Methods: Data ( N= 208,220, weighted N: 239,589,661) from adults >18y in the 2015 - 2019 National Surveys on Drug Use and Health (52.8% female, 68.4% non-Hispanic White, 45.6% aged ≥50y) were analyzed to estimate lifetime classic psychedelic use among those with no cancer history, past history (diagnosed > 1y ago), or recently (≤1y ago) diagnosed. Weighted prevalence of psychedelic use, 95% confidence intervals, and adjusted (sex, race, income, education) odds ratio were calculated using logistic regression analysis in SAS. Results: Overall, 6.2% had a cancer history and 14.0% reported lifetime classic psychedelics use. LSD was the most prevalent in the sample (10.6%, 95% CI:10.4-10.8) compared to Psilocybin (9.6%, 95% CI: 9.4-9.9), Mescaline (3.1%, 95% CI:3.0-3.2), and Peyote (2.3%, 95% CI:2.2-2.4). Psychedelic use was lowest in adults with past cancer diagnosis (12.3%, 95% CI:11.4-13.1) vs recently diagnosed [14.0% (95% CI:12.0-16.0] and cancer naive (14.1%, 95% CI:13.8-14.4). Each classic psychedelic was used more often among recent cancer diagnosed adults than past diagnosed (p < 0.05). Specifically, LSD (11.1%, 95% CI:9.3-12.9 vs 9.3%, 95% CI:8.5-10.0), Psilocybin (8.3%, 95% CI:6.6-10.0 vs 7.3%, 95% CI: 6.7-8.0), Mescaline (5.4%, 95% CI:4.0-6.8 vs 4.6%, 95% CI: 3.9-5.2), and Peyote (3.7%, 95% CI: 2.5-5.0 vs 2.9%, 95% CI: 2.5-3.4) use was higher in recently diagnosed cancer patients than past diagnosed. There were no significant differences in age, except among Peyote. Among 18-to-34-year-olds, recent cancer patients had 3-fold greater odds (aOR:3.55, 95%CI: 1.11-11.31) of using peyote vs cancer naïve. In ≥50-year-olds, those with past cancer diagnosis had 21% lower odds (aOR:0.79, 95% CI:0.63-0.97) of using peyote vs cancer naïve. Conclusions: Results suggest differential psychedelic use by cancer history and age. These findings, while limited by temporality of diagnosis and initiation of psychedelic use, underscore the need to investigate reasons and long-term impact of specific psychedelic use with more rigor among adults with a cancer history.

SB221: A proof-of-concept study to assess the combination of SON-1010 (IL12-FHAB) and atezolizumab in patients with platinum-resistant ovarian cancer.

TPS5629 Background: Recombinant interleukins (rIL) have had limited clinical success due to inefficient tumor targeting and short PK, requiring frequent dosing that leads to aberrant immunostimulation and toxicity. IL-12 potently activates T and NK cells to produce IFNγ and kill tumor cells, yet dosing strategies have failed to provide adequate therapeutic benefit in humans. We developed a novel platform that delivers immunomodulator(s) linked to a fully-human albumin binding (FHAB) domain (Cini, Front Immunol 2023). Single-chain native IL-12 genetically linked to the FHAB provides enhanced tumor targeting and retention through albumin binding to over-expressed FcRn, GP60, and SPARC in the tumor microenvironment (TME), with an improved PK profile, a dose-sparing effect that decreases the toxicity risk, and a broader therapeutic index. Tumor growth inhibition in an immunologically ‘cold’ B16-F10 mouse melanoma model showed the efficacy of IL12-FHAB compared with rIL-12, resulting in significant increases in activated NK, NKT, Th1, and cytotoxic CD8 T cells. SON-1010 is being studied clinically as monotherapy (study SB101) in advanced solid tumors and in healthy volunteers (study SB102) (Chawla, AACR 2023). Atezolizumab (Tecentriq), an anti-PD-L1 immune checkpoint inhibitor (ICI), has shown preliminary clinical activity in Phase 1 studies of patients with platinum-resistant ovarian cancer (PROC) (Liu, Gyn Onc 2019; Moroney, Clin Canc Res 2020). SON-1010 may ‘warm up’ the TME to improve ICI effectiveness in these immunologically-active tumors that have high levels of SPARC. Methods: Study SB221 is a Phase 1b/2a multicenter, dose-escalation and proof-of-concept study to assess the safety, tolerability, PK, PD, and efficacy of SON-1010 administered SC, either alone or in combination with a fixed dose of atezolizumab given IV (NCT05756907). The study is designed in Part 1 to rapidly establish the maximum tolerated dose (MTD) of the combination in patients with advanced solid tumors with up to 5 dose-escalation groups and to expand the dataset using patients with PROC to establish the Recommended Phase 2 Dose (RP2D). Once the likelihood of efficacy is shown in a Simon 2-stage design, this will be followed in Part 2 by an assessment of the potential for improved efficacy of the combination in patients with PROC over SON-1010 alone or the standard of care (SOC). The first dose-escalation cohorts have been enrolled and additional sites are being added to help with recruitment of patients with PROC. Combination of SON-1010 with an ICI offers a unique opportunity to use this extended PK version of IL-12 to augment the potential for tumor control in PROC, which represents a significant unmet medical need. Clinical trial information: NCT05756907 .

Characterization of the BCMA epitope bound by BCMA-CD3 T cell engager elranatamab.

7546 Background: Elranatamab is a BCMA-CD3 bispecific antibody with an accelerated approval in the US and EU for relapsed/refractory multiple myeloma (RRMM). Elranatamab binds to CD3 on T cells and BCMA on MM tumor cells; this dual binding results in T cell activation, cytokine release, and tumor cell killing. Engagement of the BCMA surface receptor by its ligands, APRIL and BAFF, mediates plasma cell proliferation and survival. Elevated BCMA, as well as BAFF and APRIL are present in MM patients, yet in vitro functional assays have shown physiologically relevant soluble APRIL or BAFF concentrations did not significantly impact elranatamab activity. Moreover, emerging clinical data from relapsed patients has identified novel, yet relatively rare BCMA protein mutations that may impact BCMA ligand or targeted modality binding. Here we characterized the BCMA binding affinity, evaluated the impact on BCMA binding to BAFF and APRIL interactions, and identified the BCMA binding epitope. We also generated a model from crystal structure data to map reported BCMA mutations identified in patients. Methods: Elranatamab binding affinity to recombinant human BCMA and characterization of BAFF and APRIL interactions with elranatamab-bound BCMA were calculated via SPR at 37˚C with a classical sandwich format. The elranatamab BCMA binding epitope was identified by a co-crystal structure with a parental anti-BCMA Fab that has identical CDR sequences to elranatamab. Alpha-fold modeling was used to map identified BCMA mutations on the antibody/BCMA interface. Results: Elranatamab binds to BCMA with higher affinity (~38 pM) compared to reported binding affinities of BAFF (μM range) and APRIL (nM range) ligands. The identified elranatamab epitope largely overlaps with known ligand epitopes, supporting that elranatamab higher affinity BCMA binding blocks ligand binding. Alpha fold modeling of four recently reported rare BCMA mutations shows that they lie along the binding interface. Conclusions: Due to its high affinity for BCMA, elranatamab potency is unlikely to be impacted by elevated levels of soluble BAFF or APRIL in RRMM patients. Future studies are needed to characterize the impact of emerging MM patient BCMA mutations on the binding and function of anti-BCMA targeting modalities, particularly given the small extracellular domain of BCMA available for therapeutic targeting and the highly overlapping binding epitopes reported for approved BCMA agents.

EMITT-1: Proof-of-mechanism immunopeptidome (ImPD) effects at target PK exposure, in a phase 1 study of GRWD5769 (a first-in-class inhibitor of Endoplasmic Reticulum Aminopeptidase 1 [ERAP1]) in patients with solid malignancies.

2589 Background: GRWD5769 is a first-in-class, orally bioavailable ERAP1 inhibitor that significantly modulates the peptide repertoire displayed on MHC-1 on tumor cells, driving novel T cell response and causing tumor cell killing in preclinical studies. This unique approach has potential to overcome central mechanisms of immune resistance by driving de-novo recognition of previously hidden tumor neoantigens and addressing T cell exhaustion. Here we report initial safety, pharmacokinetic (PK) and pharmacodynamic (PD) endpoints from Part A (monotherapy dose escalation) in the ongoing multicentre, modular phase I dose escalation study (ACTRN12623000108617). Methods: Patients with advanced refractory solid tumors are enrolled using a BOIN escalation design. GRWD5769 is administered BID on days 1-14 during 21-day cycles. The first cycle is the dose-limiting toxicity (DLT) observation period. The PK / PD relationship of GRWD5769 is being evaluated using mass spectrometry analysis of the ImPD. Tumor responses are evaluated by RECIST v1.1 / iRECIST. Results: As of 03 January 2024, a total of 12 patients had been treated with GRWD5769 in 3 dose cohorts (25 mg, 50 mg, 100 mg BID). On average patients have remained on treatment for 4 cycles (range 1-10) No Serious Adverse Reactions, DLTs, immune related AEs or deaths were reported. Two Gr 3 serious adverse events have occurred in 2 treated subjects (aspiration pneumonia and Urinary Tract Infection, neither attributable to GRWD5769). Gr 1+2 AEs were infrequent and manageable. PK analyses for the first 3 cohorts show dose proportional plasma levels, with Tmax at ~3 h and a ~8 h Thalf. The minimum biologically active dose (MBAD) is defined as an average steady state plasma concentration above the IC50 for ERAP1, which was achieved at the 100 mg BID dose level. PD data shows dose-dependent target engagement, with marked shifts in the ImPD. This is consistent with the expected mechanistic effects of ERAP1 inhibition seen in preclinical models and is the first demonstration that the human ImPD can be manipulated pharmacologically in cancer patients, potentially allowing T cells to recognise new targets on tumors. Dose escalation with GRWD5769 monotherapy continues to determine the recommended phase 2 dose (RP2D). GWRD5769 in combination with Immune Checkpoint Inhibition will be investigated in Part B now that the MBAD has been reached. Conclusions: GRWD5769 has been well tolerated at doses up to 100 mg BID. PK / PD data support dose-dependent target engagement of ERAP1. Proof of mechanism has been achieved for this first-in-class therapy, and this is the first demonstration that the human ImPD can be manipulated pharmacologically in cancer patients. Further PD analyses will explore shifts in the T cell repertoire and modulation of immune cell phenotypes. Clinical trial information: ACTRN12623000108617.

Impact of drug dispersion on tumor-effector dynamics during combined chemo-immunotherapy with sensitivity analysis

Solid cancer remains a serious threat to global health despite decades of progress. Traditional chemotherapy treatment has been used to curb the disease despite its inability to reach cancer cells at high enough quantities leading to adverse toxicity on healthy cells, producing severe side effects, and exacerbating patient suffering. Active targeted nano-drugs (ATNDs) acting as transporter systems have become a viable solution to this shortcoming, offering the possibility of more precise cancer targeting. Therefore, in the present study, we develop a numerical model of capturing ATNDs, incorporating movements within and outside the tumor spheroid and the magnetic forces guiding the nanoparticles. By combining a model of ATNDs transport with a tumor-effector dynamic model based on porous media phenomena, we demonstrate how the models may be combined to model drug-loaded nanoparticle transport in an external magnetic field. We analyze the controlled drug delivery against traditional chemotherapy based on the combined effect of immunotherapy and chemotherapy with the dispersion of nano-drugs to lead a solute cloud toward the tumor. We found that the amalgamation of immune and chemotherapy delivered by ATNDs enhances cancer therapy efficacy compared with conventional chemotherapy. Increased drug convection toward the tumor region presented by ascending values of the Peclet number inhibits the growth of tumor cells and prolongs progression-free survival. Increases in source term and vessel permeability also increase the likelihood of tumor suppression, while raising the hematocrit and magnetic number results in reduced tumor cell killing. Sensitivity analysis of the dynamic model parameters has been discussed. This work demonstrates that ATND-delivery systems can improve therapeutic agent delivery to the tumor tissue, and promote tumor cell killing.

Time restricted eating (TRE) and immunotherapy outcomes in head and neck squamous cell carcinoma (HNSCC) via modulation of microbial butyrate and tryptophan metabolic pathways.

e18028 Background: Metastatic HNSCC continues to have very poor prognosis. Only a fraction of patients respond to immune checkpoint blocker therapy (ICB), with no effective treatment options for non-responders. Gut microbial composition and diversity have been associated with response to ICB in many cancers including HNSCC. We have previously demonstrated that TRE significantly improved progression free survival via modulation of gut microbiota. We herein report our mechanistic data demonstrating critical role of microbially mediated butyric and tryptophan metabolic pathways in augmenting antitumor immune response to ICB. Methods: Paired blood and stool samples, at baseline and at first response assessment, from 43 HNSCC patients enrolled in the TRE study (NCT05083416) was collected and analyzed using untargeted and targeted metabolomics, focusing on tryptophan and short chain fatty acid pathway. Further shot gun metagenomic sequencing was conducted on stool samples. Finally, we performed an in vitro luciferase cytotoxicity assay using SCC-4 human cancer cells to demonstrate TRE mediated antitumor immune response. We co-cultured MHC-I and NY-ESO-1, and NY-ESO-1-specific TCR-transduced T cells. tumor cells and the T cells under different conditions of butyrate concentration and T cell-to-tumor cell ratio (1:5, 1:10) and evaluated T cell mediated tumors killing. Results: We noted significantly higher abundance of clostridium butyricum (OR-1004, p-0.0002) with corresponding higher expression of butyrate kinase enzyme in stool of patients who observed TRE (OR-1.9, p-0.0003) vs those who did not, leading to higher concentration of fecal butyric acid and hydroxy indole acetic acid (HIAA) (OR-4.2, p-0.003), both of which were independently associated with longer progression free survival (HR-0.9, p<0.01). Higher abundance of butyric acid in gut is known to enhance the gut barrier function with consequent decrease in plasma butyrate and HIAA, lower systemic levels of which, was found to be associated with longer progression free survival in our cohort (OR-0.9, p-0.05). Both butyrate and 5HIAA are known activators of immunosuppressive aryl hydrocarbon receptor (AhR) expressed on cytotoxic CD8T cells, inhibiting CD8 mediated antitumor response. In line with our hypothesis, we observed that butyrate and 5HIAA impaired CD8 T mediated T cell killing of tumor cells in a dose-dependent manner. Conclusions: These results suggest that TRE favorably modulates ICB response via enrichment of gut microbiota with butyrate producing microbial organism, leading to increased abundance of gut butyrate and microbial tryptophan metabolites and their consequent reduction in systemic circulation, ultimately enhancing antitumor immune response.

Effect of 1-L-MT on immunotherapy of diffuse large B-cell lymphoma via downregulation of PD-L1.

e19066 Background: Diffuse large B-cell lymphoma (DLBCL) is the most common lymphoma, accounting for more than 30% of all cases. Although with the development of treatment, the 5 years overall survival rates remain low, range from 30%-50% for all DLBCL patients. In addition to R-CHOP, immunotherapy has attracted much attention. However, the single-agent activity of most immune checkpoint inhibitors (ICI) in DLBCL has been overwhelmingly disappointing. It is urgent to develop new methods to enhance the efficacy of DLBCL treatment. Our previous study demonstrated that 1-L-MT, an IDO1 inhibitor, can inhibit tumor growth of DLBCL. Here, we investigate whether 1-L-MT promotes antitumor immunity of ICI in DLBCL. Methods: The role of 1-L-MT on cell proliferation in vitro and tumor growth in NOD/SCID mice were investigated. RNA-seq analysis was performed in 1-L-MT treated and control OCI-Ly10 cells. ChIP assay was performed using AhR-precipitated DNA samples of OCI-Ly10 cells (treated with or without 1-L-MT) and primers for PD-L1, and he expression of PD-L1 was evaluated by RT-qPCR. The combination of 1-L-MT and PD-1 blockade therapy were performed in C57BL/6 mouse bearing tumor cells to evaluate the antitumor activity. Results: In our study, IDO1 inhibitor 1-L-MT sensitized diffuse large B cell lymphoma to immunotherapy via downregulation of PD-L1. Further study confirmed that 1-L-MT could reduce the expression of PD-L1 and upregulate the expression of MHC-I antigen presentation factors. In addition, RNA-seq and bioinformatics analysis revealed that the transcription factor AhR may involved in the downregulation of PD-L1 transcription level induced by 1-L-MT. Mechanistically, ChIP and RT-qPCR assays were conducted to test AhR-PD-L1 interaction, and the results showed that AhR directly bound the promoter of PD-L1. 1-L-MT-mediated PD-L1 reduction promoted T cell activation and T cell killing of tumor cells. The combination of 1-L-MT and anti PD-1 antibody significantly inhibited DLBCL growth and extends the lifespan of tumor-bearing mice. Conclusions: Our study unveiled a mechanism by which 1-L-MT induces PD-L1 downregulation via AhR and provides methods to facilitate immunotherapy in diffuse large B-cell lymphoma. The present study may provide a theoretical foundation for overcoming the challenge of low-sensitivity to immunotherapy in DLBCL.

Effect of Thermoablation with pH Change on Giant Cell Tumor of Bone: An In Vitro Study

Objective: To evaluate the effect of pH on the apoptosis and necrosis rate of giant cell tumor of bone (GCTB) cells during thermoablation. Materials and Methods: GCTB tissues were collected from 15 patients. Cells were incubated at 25 ºC , 37 ºC, 45 ºC, and 50 ºC, with the variation of the pH at 4.7, 5.6, 6.5, 7.4, 8.3, and 9.2 for 20 minutes (in triplicate for each condition). The effect of thermoablation and pH variation on GCTB cells death was evaluated by staining with Annexin V-FITC and propidium iodide solution after 3 days of incubation. The fluorescence intensity was evaluated by flow cytometry to evaluate the percentage of tumor cells death. Results: Thermoablation alone increased the percentage of tumor cells death. However, when combined with an increase in pH, the percentage of GCTB cells death increased more. Conversely, lowering the pH did not increase the tumor cells death compared with thermoablation treatment alone, while changing the pH alone had only a low effect on increasing the percentage of GCTB cells death. Conclusion: Thermoablation the temperature between 37 ºC and 45 ºC plus a pH level slightly higher than physiologic pH (between 7.4 and 8.3) for 20 minutes increased GCTB cell death. However, determining the optimum condition to kill tumor cells while causing minimal harm to normal cells requires more study.

First-in-human study of ZGGS15, a dual specific antibody targeting LAG-3 and TIGIT, as monotherapy in patients with advanced solid tumors.

e14678 Background: ZGGS15 is a recombinant humanized bispecific antibody composed of a monoclonal antibody against LAG-3 and TIGIT. It can specifically bind LAG-3 and TIGIT. It reverses LAG-3 and TIGIT immune suppression to T and NK cells, relieves suppression of Treg to T and NK cells, promotes the activation and proliferation of T and NK cells, and cytokines release. ZGGS15 restores T and NK cell functions to kill tumor cells. In non-clinical studies, we found that ZGGS15 had significant anti-tumor effects and synergistic anti-tumor effects with Anti-PD-1 antibody. Therefore, we conducted a Phase 1 clinical study to assess the tolerability, safety, and preliminary efficacy of this drug as monotherapy in patients with advanced solid tumors. Methods: During the dose escalation stage, an accelerated titration design (ATD) in the first dose (1 subject if ≤Grade 2 treatment-related adverse event occurred) and the standard "3+3" design in the rest doses were used. Subjects were patients with advanced solid tumors who failed to the available standard treatments. The dose groups were set from 0.3 to 30 (0.3, 1, 3, 10, 20, 30) mg/kg, intravenous infusion, once every 3 weeks. The first 21-day period was defined as the dose-limiting toxicity (DLT) observation period. Subjects could continue to receive ZGGS15 until treatment discontinuation criteria were met. Tumor response was assessed by RECIST1.1 and iRECIST. Pharmacokinetics (PK) and receptor occupancy (RO) profiles were also assessed in this study. Results: A total of 12 patients (4 males and 8 females) completed the DLT observation in the first four dose groups (0.3 to 10 mg), with a median age of 57 years. Eight (66.7%) of them received at least 3 lines of antineoplastic therapies, and five (41.7%) have been exposed to PD-1 or PD-L1 inhibitors. There was no DLT event observed. Thirty-eight treatment-related adverse events (TRAEs) occurred. Up to now, TRAEs were all grade 1 ~ 2. The most frequent TRAEs were proteinuria (33.3%, 4/12), hypokalemia (25%, 3/12), hypoalbuminemia (25%, 3/12), and hypertriglyceridemia (25%, 3/12). The Cmax and AUC increased from 0.3-1 mg/kg approximately in dose proportion. Nearly complete and sustained RO of T and NK cells in PBMCs was observed at 1 mg/kg dose of ZGGS15 for at least 3 weeks. Conclusions: The first four dose levels of ZGGS15 were very well tolerated. A good PK profile, and a long-lasting RO were observed in this escalation study. It is anticipated that this product could provide an additional benefit only when use in combination with an anti-PD-1 antibody. Clinical trial information: NCT05864573 .

Discovery of HDM2010, a highly potent PTPN2 inhibitor for immunotherapy.

e15021 Background: Protein tyrosine phosphatase non-receptor type 2 (PTPN2), a negative regulator of JAK–STAT pathways that plays a crucial role in the immune system, has been identified as a promising target for immunotherapy. Genetic deletion of PTPN2 in either tumor cells or host immune cells promotes the anti-tumor immunity. In addition, PTPN2 inhibitors, alone or in combination with anti-PD1 therapy, significantly reduced tumor growth and enhanced survival in several subcutaneous tumour models. These findings demonstrate that PTPN2 inhibitors may have clinical benefits for immunotherapy-resistant tumors. Herein, the discovery of a series of novel PTPN2 inhibitors and their implications for immunotherapy are reported. Methods: We have successfully developed a series of small molecule inhibitors that specifically target PTPN2/N1. Molecular design was based on a novel backbone and incorporating both structure-based drug design (SBDD) and computational chemistry techniques. To evaluate the efficacy of our inhibitors, PTPN2 phosphatase activity was monitored using the small-molecule substrate DiFMUP in a fluorescence assay format in vitro. Tumor cells were treated with IFNγ and the cell viability was measured. Pharmacokinetic studies were conducted in mice, with serial blood samples analyzed by liquid chromatography−mass spectrometry (LC−MS)/MS. Pharmacokinetic parameters were calculated by noncompartmental analysis. Results: Based on the co-crystal structure of this target reported and multiple previous research projects, we have designed a multitude of novel compounds with the employment of computer-aided drug design (CADD) and scaffold hopping. Through a comprehensive evaluation of the in vitro and in vivo parameters, we have identified a series of compounds displaying potent PTPN2 inhibition (IC50 < 10 nM). Moreover, the compounds displayed remarkable efficacy in killing tumor cells to IFNγ treatment (IC50 < 100 nM). Artificial intelligence was utilized to conduct assessment and prediction of ADME properties, improving the drug-ability including permeability and physicochemical properties. Currently, a series of compounds demonstrating outstanding potency and good pharmacokinetic profiles, with lower hERG blockage (hERG IC50 > 30 µM), were synthesized and characterized. Among these hit compounds, a leading compound with PTPN2 IC50 = 1.1 nM and tumor cells IC50 = 79.5 nM was identified for further optimization and evaluation. Conclusions: We reported our work on discovering HDM2010, in which a series of potent PTPN2 inhibitors with prominent PK and safety profile were synthesized and characterized. Further optimization including in vivo experiments will lead to a preclinical candidate (PCC) selection.

A first-in-human (FIH), phase 1/2, dose-escalation, dose-optimization, and dose-expansion study of PARP1-selective inhibitor IMP1734 in participants with advanced solid tumors.

TPS3191 Background: PARP inhibitors (PARPi) selectively kill tumor cells harboring genetic mutations in critical DNA repair genes (e.g., BRCA1/2). While several approved nonselective PARPi have provided robust anti-tumor activity, they are associated with significant hematologic toxicities that limit dose intensity and clinical benefit. Drugs that selectively inhibit PARP1 but spare PARP2 may improve the risk-benefit profile for this class of therapies by retaining anti-tumor activity while avoiding PARP2-related toxicities. IMP1734 (EIK1003) is a potent PARP1-selective inhibitor that inhibits tumor growth in nonclinical models and may widen the therapeutic index in tumors where non-selective PARPi have demonstrated efficacy. Methods: Study EIK1003-001 (IMP1734-101) is a global, multi-center, Phase 1/2 study evaluating the safety and potential antitumor activity of IMP1734 in participants with advanced solid tumors. The study has 3 parts: Part 1 (FIH; Dose Escalation), Part 2 (Dose Optimization), and Part 3 (Dose Expansion at the recommended dose for expansion [RDE]). Part 1 of this study is currently enrolling and consists of dose escalation of IMP1734 in study participants with advanced/recurrent/metastatic ovarian, breast, or prostate cancer with suspected deleterious/deleterious mutations in a pre-specified panel of homologous recombination repair (HRR) genes (n = 70). Eligible participants must be ≥ 18 years of age, have histologically or cytologically confirmed tumors as indicated in each study part, and at least 1 RECIST v1.1-measurable lesion and/or pre-specified serum tumor-specific marker. All participants must have a deleterious or suspected deleterious mutation in select HRR genes. Primary endpoints include safety and tolerability (evaluation of dose-limiting toxicities and determining the maximum tolerated dose, maximum achievable dose, and RDE). Secondary endpoints include evaluation of the pharmacokinetic parameters of IMP1734 and measures of efficacy, including overall response rate, duration of response, progression-free survival, and overall survival. Exploratory endpoints include analysis of pharmacodynamic biomarkers, serial ctDNA measurements, and patient quality-of-life measures. This study opened on 11 Dec 2023. Clinical trial information: NCT06253130 .

Eosinophils in Colorectal Cancer: Emerging Insights into Anti-Tumoral Mechanisms and Clinical Implications.

Eosinophils are myeloid effector cells whose main homing is the gastrointestinal tract. There, they take part in type I and type II immune responses. They also contribute to other non-immunological homeostatic functions like mucus production, tissue regeneration, and angiogenesis. In colorectal cancer (CRC), eosinophils locate in the center of the tumor and in the front of invasion and play an anti-tumoral role. They directly kill tumor cells by releasing cytotoxic compounds and eosinophil extracellular traps or indirectly by activating other immune cells via cytokines. As CRC progresses, the number of infiltrating eosinophils decreases. Although this phenomenon is not fully understood, it is known that some changes in the microenvironmental milieu and microbiome can affect eosinophil infiltration. Importantly, a high number of intratumoral eosinophils is a favorable prognostic factor independent from the tumor stage. Moreover, after immunotherapy, responding patients usually display eosinophilia, so eosinophils could be a good biomarker candidate to monitor treatment outcomes. Finally, even though eosinophils seem to play an interesting anti-tumoral role in CRC, much more research is needed to fully understand their interactions in the CRC microenvironment. This review explores the multifaceted roles of eosinophils in colorectal cancer, highlighting their anti-tumoral effects, prognostic significance, and potential as a biomarker for treatment outcomes.

Combinatorial cellular therapy in pediatric solid tumors with natural killer (NK) and genetically engineered myeloid cells (GEMys).

2561 Background: Early human studies with Natural Killer (NK) cells have shown promise, harnessing their ability to infiltrate into tumors and be tumoricidal. However, these effects can be limited by adenosine, reactive oxygen species, and TGF-β in the highly immune suppressive tumor microenvironment (TME). TGF-β and downstream SMAD3 signaling in Natural Killer (NK) cells have been shown to cause decreased cytokine production, downregulation of activating cell surface receptors, and attenuated cytotoxic function against solid tumors. Exposure to TGF-β during cell culture generates expanded NK cells with increased resistance to TGF-β signaling, dubbed TGF-β imprinted NK cells. In vitrostudies have shown that these cells have increased cytokine production and cytotoxic function in the presence of TGF-β. However, their in vivo trafficking, modulation of the TME, and therapeutic efficacy remain understudied. Our lab has previously shown that when given to tumor-bearing mice, myeloid cells modified to produce IL-12 (IL-12-Genetically Engineered Myeloid cells, aka IL-12 GEMys) are effective at homing to tumor and metastatic sites and, via IL-12 secretion and TME modulation, increase NK cell presence and activation in these sites. They hold great promise as combination therapy, enhancing the effectiveness of other cellular therapies such as NK cell therapy. A current clinical trial exploring TGF-β Imprinted, Ex Vivo Expanded, Universal Donor NK Cell Infusions in relapsed sarcomas is underway (NCT05634369). Methods: In vitro experiments were conducted with the xCELLigence real-time cell analysis system. The human osteosarcoma cell line 143B and human rhabdomyosarcoma cell line RH-30 were evaluated for cell death after co-culture with healthy donor NK cells or TGF-β imprinted NK cells (E:T ratio of 5:1) in isolation and in combination with IL-12 GEMys (E:T ratio of 2:1). Results: TGF-β imprinted NK cells are significantly more effective at tumor cell killing of both 143B and RH30 cell lines in-vitro compared to regular expanded NK cells (WT NK cells), with >90% decrease in cell index compared to 50-60%, respectively, after 48 hours of co-culture. IL-12 GEMys also significantly enhance the cytotoxic effects of WT NK cells, increasing cell killing to 70-80% compared to co-culture with untransduced GEMy controls. Conclusions: These initial in-vitro experiments provide insight into the promising effectiveness of NK-myeloid cell combination therapies in the treatment of pediatric sarcomas. Ongoing in vitroexperiments include cytokine quantification by ELISA and flow cytometric analysis of NK cell activation and proliferation markers. Our preliminary results provide rationale to continue studying the in vivo efficacy of TGF-β imprinted NK cell monotherapy and in combination with IL-12 GEMys in the treatment of tumor-bearing NSG mice.

Example of a simple and scalable manufacturing process for immunomodulatory alpha neutrophils, a specifically designed immuno-cell therapy with direct and indirect anti-cancer activity for solid tumour indications.

e14512 Background: Recent findings have demonstrated neutrophils play a key role in tumour control and in facilitating successful responses to cancer immunotherapy. At LIfT Biosciences we have developed the first-in-class, allogeneic, off-the-shelf, stem cell-derived immuno-cell therapy with anti-cancer neutrophil properties. Immunomodulatory Alpha Neutrophils (IMANs) exert their anti-cancer activity via multiple direct and indirect mechanisms, ensuring direct antigen-independent tumour cell killing, as well as impacting anti-cancer function of other direct acting cells such as NK and gamma delta T cells, and further immunomodulation of the environment to boost adaptive immune responses ensuring maximal T cell activity can be achieved. IMANs have the potential to provide major clinical benefits in the treatment of multiple solid tumours. Methods: We present a patent-pending, GMP-compliant manufacturing process starting with CD34+ cells isolated from mobilized peripheral blood of healthy donors. Extensive characterisation of starting material in combination with in-process and raw material controls results in a simple, consistent, scalable manufacturing process using known and established manufacturing platforms. IMANs are granulopoietic myeloid progenitors derived from the expansion of CD34+ cells followed by differentiation in proprietary media compositions, composed of critical priming agents which are known to promote anti-cancer neutrophil phenotype and function. Neutrophil functional heterogeneity is becoming increasingly appreciated and we have designed our manufacturing process to produce activated, committed, persistent IMANs with multimodal mechanisms of action. IMANs are composed of distinct neutrophil progenitor populations. IMANs are cytotoxic towards numerous solid tumour cell lines, expressing tumour-ablating Neutrophil elastase. Furthermore, IMANs exert immunomodulatory properties through cytokine and chemokine secretion, and expression of ligands for T and NK cell co-stimulatory receptors. Results: The manufacturing process has been optimised with vast expansion capacity, showing up to 1000-fold increase from starting cell populations and efficient cryopreservation with exceptional post-thaw recovery. Conclusions: Cryopreserved IMANs offer a cost-effective and globally accessible cell therapy with the potential for long term clinical benefit.

Phase 2 study of bizaxofusp, an IL-4R targeted toxin payload, in nonresectable recurrent GBM: Comparison of overall survival with contemporaneous eligibility-matched and propensity score balanced external control arm.

2079 Background: Bizaxofusp (MDNA55) is designed to selectively deliver a potent toxin payload to tumor cells by targeting the IL-4 receptor (IL-4R) overexpressed by GBM, but not normal brain. Localized delivery of bizaxofusp minimizes risk of off-target toxicities and systemic exposure while eliciting effective tumor cell killing. Bizaxofusp was evaluated using convection-enhanced delivery in MDNA55-05 (NCT02858895), a single-arm, open-label, multi-center Ph2 study in nonresectable recurrent GBM (rGBM). Methods: The study population comprised of de novo IDH wild-type GBM patients with 1st or 2nd relapse that were non-resectable. Forty-four patients were administered a single treatment of bizaxofusp (range: 18-240 μg). The primary endpoint was OS; secondary endpoints were safety and tumor response. IL-4R expression in tumor biopsies was determined using a validated assay. OS was compared to an eligibility matched external control arm (emECA) of 81 contemporaneous rGBM subjects receiving standard of care. The emECA was further refined by propensity-score balancing (pbECA) to the bizaxofusp arm based on known prognostic factors, resulting in a weighted sample size of 40.8. OS was defined as time from relapse (to unify index date in both arms) or treatment start (for analysis of tumor response) to death/censor. Tumor response was assessed following RANO and mRANO criteria. Results: Bizaxofusp showed an acceptable safety profile at doses up to 240 μg. TRAEs were primarily neurological or aggravation of pre-existing neurological deficits associated with GBM and were manageable with standard measures. Results showed that IL-4R expression did not impact mOS except in patients receiving low doses of bizaxofusp. The bizaxofusp arm had significantly longer median OS (mOS) than contemporaneous emECA (12.4 vs 7.7 months; HR: 0.64, 95% CI 0.46-0.93; p = 0.02). Survival benefit was also evident when compared to the pbECA: (12.4 vs 7.2 months; HR: 0.72, 95% CI 0.46-1.1; p = 0.27). Patients with tumor control (SD or PR/CR, n=21) had significantly longer mOS than patients with tumor progression (n=23) (16.7 vs 8.5 months; HR = 0.5, 95% CI 0.27-0.9; p = 0.01). Among patients with tumor control who had pseudoprogression (PsP) per mRANO, mOS (22.8 months) was significantly longer than patients with tumor progression (HR: 0.49, 95% CI 0.25-0.98; p = 0.049). Conclusions: Bizaxofusp achieved significant OS benefit in patients with nonresectable rGBM compared to contemporaneous emECA. Patients who experienced tumor control, including those with PsP, showed significantly longer survival than patients with tumor progression. Phase 3 ready registrational trial will comprise a high dose bizaxofusp arm and a hybrid control arm with 1/3 randomized subjects and 2/3 pmECA. Clinical trial information: NCT02858895 .

How Fundamental Research on T cell Biology Started a Revolution in Cancer Therapy Development

In the dynamic landscape of cancer treatment, discovery-based research in T cell biology has proven transformative, ushering in revolutionary immunotherapies. This paper navigates the impact of fundamental research on cancer therapy, tracing its evolution from 19th-century trailblazers Wilhelm Busch and Friedrich Fehleisen to recent breakthroughs by James P. Allison. By understanding T cells, the immune system's superheroes, we can illuminate the pivotal role of selectively targeting and eliminating cancer cells with unprecedented precision. Advances such as checkpoint blockade antibodies have freed tumor-infiltrating T cells from inhibition, allowing them to kill tumor cells effectively. This was a revolutionary breakthrough. Historical insights, such as the discovery of immunocompetent recirculating lymphocytes and the function of the thymus, laid the groundwork for these advances. This ongoing dialogue on resource allocation recognizes foundational research as the cornerstone for innovative therapies, ensuring a sustainable pipeline of discoveries that shape the future of T cell cancer treatment.

Developing oxaliplatin and IL-15 Co-carried gels as drug depots to enable triple-interlocked combination therapy for colorectal cancer

Chemo-immunotherapy, which involves the simultaneous use of chemotherapy drug and immunotherapeutic agent to achieve synergistic effects, plays a crucial role in cancer treatment. However, the immunosuppressive microenvironment, insufficient tumor specificity, and serious systemic side effects hinder their synergistic therapeutic effects and clinical applications. Herein, T cell and natural killer (NK) cell, which are the most important immune effector cells, were both activated to reverse the immunosuppressive microenvironment. To simplify drug carriers, oxaliplatin was selected as the chemotherapy drug which can both induce the ICD effect and activate T cells. IL-15 was selected to activate NK cells. To enhance the productivity of the carrier and reduce side effects, the easy-prepared thermosensitive hydrogel (OXL/IL-15 TG) was developed to co-load oxaliplatin-loaded liposomes (OXL) and IL-15. Colorectal cancer, suitable for in situ administration, was selected as model cancer. The resulting novel triple-interlocked combination therapy could directly kill the tumor cells, induces ICD effect and activate NK cells. After administration, OXL/IL-15 TG was formed serving as a drug depot, slowing releasing OXL and IL-15 non-interferencely. OXL around 165.47±7.04 nm was passively delivered to tumor tissue, killing tumor cells and inducing ICD effect. The results demonstrated that IL-15 stimulated the activation of NK cells. In tumor-bearing mice models, OXL/IL-15 TG exhibited a remarkable and noteworthy anti-tumor efficacy, and expanded survival rate. Notably, OXL/IL-15 TG led to an enhanced infiltration of CD3+CD8+ T cells and CD3-CD49+ NK cells within the tumor tissue. Overall, the triple-interlocked combination therapy provided a new idea for colorectal cancer therapy.

Structural and functional characterization of IgG- and non-IgG-based T-cell-engaging bispecific antibodies.

Bispecific T-cell-engaging antibodies are a growing class of therapeutics with numerous molecules being tested in clinical trials and, currently, seven of them have received market approval. They are structurally complex and function as adaptors to redirect the cytotoxicity of T cells to kill tumor cells. T-cell-engaging bispecific antibodies can be generally divided into two categories: IgG/IgG-like and non-IgG-like formats. Different formats may have different intrinsic potencies and physiochemical properties, and comprehensive studies are needed to gain a better understanding of how the differences in formats impact on structural and functional characteristics. In this study, we designed and generated bispecific T-cell-engaging antibodies with IgG-like (DVD-Ig) and non-IgG (BiTE) formats. Both target the same pair of antigens (EGFR and CD3) to minimize the possible influence of targets on functional characterization. We performed a side-by-side comparison to assess differences in the physiochemical and biological properties of these two bispecific T-cell-engaging antibodies using a variety of breast and ovarian cancer cell-based functional assays to delineate the structural-functional relationships and anti-tumor activities/potency. We found that the Fc portion of T-cell-engaging bispecific antibodies can significantly impact antigen binding activity, potency, and stability in addition to eliciting different mechanisms of action that contribute the killing of cancer cells.

Engineering Dimeric EGFR-directed IgA Antibodies Reveals a Central Role of CD147 during Neutrophil-mediated Tumor Cell Killing of Head and Neck Squamous Cancer Cells.

Human IgA Abs engage neutrophils for cancer immunotherapy more effectively than IgG Abs. Previous studies demonstrated that engineering approaches improved biochemical and functional properties. In this study, we report a novel, to our knowledge, IgA2 Ab against the epidermal growth factor receptor generated by protein engineering and polymerization. The resulting molecule demonstrated a covalent linkage of L and H chains and an effective polymerization by the joining chain. The engineered dimer outperformed its monomeric variant in functional experiments on Fab-mediated modes of action and binding to the Fc receptor. The capacity to engage neutrophils for Ab-dependent cell-mediated cytotoxicity (ADCC) of adherent growing target cancer cells was cell line dependent. Although the engineered dimer displayed a long-term efficacy against the vulva carcinoma cell line A431, there was a notable in-efficacy against human papillomavirus (HPV)- head and neck squamous cell carcinoma (HNSCC) cell lines. However, the highly engineered IgA Abs triggered a neutrophil-mediated cytotoxicity against HPV+ HNSCC cell lines. Short-term ADCC efficacy correlated with the target cells' epidermal growth factor receptor expression and the ability of cancer cell-conditioned media to enhance the CD147 surface level on neutrophils. Notably, the HPV+ HNSCC cell lines demonstrated a significant increment in releasing soluble CD147 and a reduced induction of membranous CD147 on neutrophils compared with HPV- cells. Although membranous CD147 on neutrophils may impair proper IgA-Fc receptor binding, soluble CD147 enhanced the IgA-neutrophil-mediated ADCC in a dose-dependent manner. Thus, engineering IgA Abs and impedance-based ADCC assays provided valuable information regarding the target-effector cell interaction and identified CD147 as a putative critical parameter for neutrophil-mediated cytotoxicity.