Inhibitor Of Tumor Growth Research Articles

The methionine cycle and its cancer implications.

The essential amino acid methionine is a crucial regulator of sulfur metabolism in a variety of interconnected biochemical pathways. The methionine cycle is intricately linked to the folate cycle, forming the one-carbon metabolism, a crucial regulator of S-adenosylmethionine, SAM. Recent work highlights methionine's critical role in tumor growth and progression, maintaining polyamine synthesis, and playing a crucial role in the regulation of SAM both in altered chromatin states, depending on p53 status, as well as facilitating m6A methylation of NR4A2 mRNA, hence regulating proliferation in esophageal carcinoma. Accordingly, Celecoxib, a specific NR4A2 inhibitor, is a potentially powerful inhibitor of tumor growth at least in this specific model. Additionally, formaldehyde, from endogenous or exogenous sources, can directly regulate both SAM steady-state-levels and the one-carbon metabolism, with relevant implication in cancer progression. These recent scientific advancements have provided a deeper understanding of the molecular mechanisms involved in cancer development, and its potential therapeutic regulation.

Tumor-associated macrophages: A sentinel of innate immune system in tumor microenvironment gone haywire.

The tumor microenvironment (TME) is a critical determinant in the initiation, progression, and treatment outcomes of various cancers. Comprising of cancer-associated fibroblasts (CAF), immune cells, blood vessels, and signaling molecules, the TME is often likened to the soil supporting the seed (tumor). Among its constituents, tumor-associated macrophages (TAMs) play a pivotal role, exhibiting a dual nature as both promoters and inhibitors of tumor growth. This review explores the intricate relationship between TAMs and the TME, emphasizing their diverse functions, from phagocytosis and tissue repair to modulating immune responses. The plasticity of TAMs is highlighted, showcasing their ability to adopt either protumorigenic or anti-tumorigenic phenotypes based on environmental cues. In the context of cancer, TAMs' pro-tumorigenic activities include promoting angiogenesis, inhibiting immune responses, and fostering metastasis. The manuscript delves into therapeutic strategies targeting TAMs, emphasizing the challenges faced in depleting or inhibiting TAMs due to their multifaceted roles. The focus shifts towards reprogramming TAMs to an anti-tumorigenic M1-like phenotype, exploring interventions such as interferons, immune checkpoint inhibitors, and small molecule modulators. Noteworthy advancements include the use of CSF1R inhibitors, CD40 agonists, and CD47 blockade, demonstrating promising results in preclinical and clinical settings. A significant section is dedicated to Chimeric Antigen Receptor (CAR) technology in macrophages (CAR-M cells). While CAR-T cells have shown success in hematological malignancies, their efficacy in solid tumors has been limited. CAR-M cells, engineered to infiltrate solid tumors, are presented as a potential breakthrough, with a focus on their development, challenges, and promising outcomes. The manuscript concludes with the exploration of third-generation CAR-M technology, offering insight into in-vivo reprogramming and nonviral vector approaches. In conclusion, understanding the complex and dynamic role of TAMs in cancer is crucial for developing effective therapeutic strategies. While early-stage TAM-targeted therapies show promise, further extensive research and larger clinical trials are warranted to optimize their targeting and improve overall cancer treatment outcomes.

Effect of PAWI-2 on pancreatic cancer stem cell tumors.

Worldwide, pancreatic cancer (PC) is a major health problem and almost 0.5million people were diagnosed with PC in 2020. In the United States, more than 64,000 adults will be diagnosed with PC in 2023. PC is highly resistant to currently available treatments and standard of care chemotherapies cause serious side effects. Most PC patients are resistant to clinical therapies. Combination therapy has showed superior efficacy over single-agent treatment. However, most therapy has failed to show a significant improvement in overall survival due to treatment-related toxicity. Developing efficacious clinically useful PC therapies remains a challenge. Herein, we show the efficacy of an innovative pathway modulator, p53-Activator Wnt Inhibitor-2 (PAWI-2) against tumors arising from human pancreatic cancer stem cells (i.e., hPCSCs, FGβ3 cells). PAWI-2 is a potent inhibitor of tumor growth. In the present study, we showed PAWI-2 potently inhibited growth of tumors from hPCSCs in orthopic xenograft models of both male and female mice. PAWI-2 worked in a non-toxic manner to inhibit tumors. Compared to vehicle-treated animals, PAWI-2 modulated molecular regulators of tumors. Anti-cancer results showed PAWI-2 in vivo efficacy could be correlated to in vitro potency to inhibit FGβ3 cells. PAWI-2 represents a safe, new approach to combat PC.

Abstract 2728: Discovery of a multispecific CD73/PD-1 targeting drug Fc-conjugate (DFC), which improves tumor reduction compared to PD-1 monotherapy in a humanized mouse model

Abstract Background: The approval of immune checkpoint therapies has revolutionized cancer treatment and established immuno-therapy as an additional treatment option. However, while anti-PD-(L)1 therapies have demonstrated durable responses, only a small subset of patients respond. One mechanism of tumor escape is via the release of immunosuppressive metabolites such as adenosine. CD73, an extracellular enzyme expressed on immune cells and some tumors, catalyzes the conversion of AMP to adenosine, the rate limiting step in adenosine production. As a strategy to improve response rates we developed a first in class CD73/PD-1 targeting DFC, comprised of a multivalent conjugate of a small molecule CD73 inhibitor stably linked to a proprietary human IgG1 Fc-fusion with a PD-1 inhibitor peptide. This multispecific DFC has the potential for differentiation and increased therapeutic potency compared to approved PD-(L)1 inhibitors. Methods: Binding of CD73/PD-1-001 to biotinylated hPD-1 was determined using ELISA and to human CD8+ T cells by flow cytometry. CD73 inhibition was measured in cell-free and cell-based assays. Efficacy was determined in a humanized mouse model optimized for PD-1 activity against a transgenic MC-38 colon cell line expressing hPD-L1 (Genoway, France). Tumor volumes were recorded and statistical analysis was conducted by t-test (Mann-Whitney) or two-way ANOVA. Results: In vitro, CD73/PD-1-001 demonstrated potent activity against both checkpoint targets. CD73/PD-1-001 bound to hPD-1 with an IC50 of < 1 nM and demonstrated functional inhibition of CD73 with an EC50 of <10 nM, which is on par with respective single agent molecules. Importantly, addition of the CD73 targeting moiety resulted in no significant loss in PD-1 binding relative to PD-1-001, a DFC containing only the PD-l inhibitor peptide. Efficacy was determined in a humanized mouse model against a transgenic MC-38 cell line. Both CD73/PD-1-001 and PD-1-001 DFCs were highly potent in this model with tumor growth inhibition (TGI) of >70% at dose concentrations of 3 mg/kg or greater (p≤0.01). However, at the lowest test concentration of 1 mg/kg, only CD73/PD-1-001 retained significant potency with a TGI of 56.0 % (p ≤ 0.05). Tumor reduction in the 1 mg/kg PD-1-001 group did not reach statistical significance (36.5%, p > 0.05). Conclusions: This work demonstrates that a multispecific CD73/PD-1 targeting DFC, is a potent inhibitor of tumor growth in a humanized mouse model. Furthermore, CD73/PD-1-001 was more potent than PD-1 monotherapy, demonstrating the therapeutic benefit of targeting two important checkpoints with a single agent molecule. Collectively, preclinical testing of a CD73/PD-1 DFC has validated the benefits of targeting the PD-(L)1 axis in combination with adenosine suppression, resulting in improved anti-tumor effects. Citation Format: James Levin, Simon Döhrmann, Nicholas Dedeic, Amanda Almaguer, Doug Zuill, Elizabeth Abelovski, Jason N. Cole, Jeffrey B. Locke, Joanne Fortier, Qiping Zhao, Maria Hernandez, Karin Amundson, Madison Moniz, Hongyuan Chen, Dhanya Panickar, Thanh Lam, Tom Brady, Allen Borchardt, Grayson Hough, Leslie W. Tari. Discovery of a multispecific CD73/PD-1 targeting drug Fc-conjugate (DFC), which improves tumor reduction compared to PD-1 monotherapy in a humanized mouse model [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2728.

Tectoridin inhibits the growth of bladder cancer by regulating PI3K/MAPK pathway through RAB27B.

Bladder cancer (BC) is a common and malignant tumor of the urinary tract, and its treatment options are limited. Tectoridin (TEC) has antitumor activity against prostate and colon cancer, but its effects on BC are poorly understood. BC cells were treated with increasing concentrations of TEC, and its effects on cell proliferation, migration, invasiveness, and apoptosis were assessed. Xenograft mouse model was used to evaluate the influences of TEC on BC tumor growth. Western blot analysis was conducted to explore the downstream pathways affected by TEC. TEC treatment decreased BC cell viability in a dose-dependent manner (IC50 ≈ 25 μM), and inhibited cell proliferation, migration, and invasiveness while promoting apoptosis. Clinical analysis revealed high expression of RAB27B in BC tumor tissues, particularly in advanced stages, correlating with an unfavorable prognosis. In vitro experiments demonstrated that TEC suppressed the PI3K/MAPK pathway by targeting RAB27B, and overexpression of RAB27B counteracted the antitumor effects of TEC. In xenograft models, TEC administration suppressed tumor growth, reduced tumor volume, inhibited cell proliferation, and suppressed the PI3K/MAPK pathway, highlighting its potential as an inhibitor of tumor growth. TEC suppresses BC tumor growth by targeting RAB27B and inactivating the PI3K/MAPK signaling and may provide a promising therapeutic target for BC treatment.

Bis-Indole Derivatives as Dual Nuclear Receptor 4A1 (NR4A1) and NR4A2 Ligands.

Bis-indole derived compounds such as 1,1-bis(3'-indolyl)-1-(3,5-disubstitutedphenyl) methane (DIM-3,5) and the corresponding 4-hydroxyl analogs (DIM8-3,5) are NR4A1 ligands that act as inverse NR4A1 agonists and are potent inhibitors of tumor growth. The high potency of several DIM-3,5 analogs (IC50 < 1 mg/kg/day), coupled with the >60% similarity of the ligand-binding domains (LBDs) of NR4A1 and NR4A2 and the pro-oncogenic activities of both receptors lead us to hypothesize that these compounds may act as dual NR4A1 and NR4A2 ligands. Using a fluorescence binding assay, it was shown that 22 synthetic DIM8-3,5 and DIM-3,5 analogs bound the LBD of NR4A1 and NR4A2 with most KD values in the low µM range. Moreover, the DIM-3,5 and DIM8-3,5 analogs also decreased NR4A1- and NR4A2-dependent transactivation in U87G glioblastoma cells transfected with GAL4-NR4A1 or GAL4-NR4A2 chimeras and a UAS-luciferase reporter gene construct. The DIM-3,5 and DIM8-3,5 analogs were cytotoxic to U87 glioblastoma and RKO colon cancer cells and the DIM-3,5 compounds were more cytotoxic than the DIM8-3,5 compounds. These studies show that both DIM-3,5 and DIM8-3,5 compounds previously identified as NR4A1 ligands bind both NR4A1 and NR4A2 and are dual NR4A1/2 ligands.

MAD2L2, a key regulator in ovarian cancer and promoting tumor progression

Ovarian cancer (OVCA), a prevalent gynecological malignancy, ranks as the fourth most common cancer among women. Mitotic Arrest Deficient 2 Like 2 (MAD2L2), a chromatin-binding protein and a component of DNA polymerase ζ, has been previously identified as an inhibitor of tumor growth in colorectal cancer. However, the roles of MAD2L2 in OVCA, including its expression, impact, and prognostic significance, remain unclear. We employed bioinformatics tools, Cox Regression analysis, and in vitro cell experiments to investigate its biological functions. Our findings reveal that MAD2L2 typically undergoes genomic alterations, such as amplifications and deep deletions. Moreover, we observed an overexpression of MAD2L2 mRNA in OVCA patients, correlating with reduced survival rates, particularly in those with Grade IV tumors. Furthermore, analysis of mRNA biofunctions indicated that MAD2L2 is predominantly localized in the organellar ribosome, engaging mainly in NADH dehydrogenase activity. This was deduced from the results of gene ontology enrichment analysis, which also identified its role as a structural constituent in mitochondrial translation elongation. These findings were corroborated by KEGG pathway analysis, further revealing MAD2L2’s involvement in tumor metabolism and the cell death process. Notably, MAD2L2 protein expression showed significant associations with various immune cells, including CD4+T cells, CD8+T cells, B cells, natural killer cells, and Myeloid dendritic cells. Additionally, elevated levels of MAD2L2 were found to enhance cell proliferation and migration in OVCA cells. The upregulation of MAD2L2 also appears to inhibit the ferroptosis process, coinciding with increased mTOR signaling activity in these cells. Our study identifies MAD2L2 as a novel regulator in ovarian tumor progression and offers new insights for treating OVCA.

Comprehensive characterization of early-programmed tumor microenvironment by tumor-associated macrophages reveals galectin-1 as an immune modulatory target in breast cancer.

Background: In recent years, there has been considerable interest in the therapeutic targeting of tumor-associated macrophages (TAMs) to modulate the tumor microenvironment (TME), resulting in antitumoral phenotypes. However, key mediators suitable for TAM-mediated remodeling of the TME remain poorly understood. Methods: In this study, we used single-cell RNA sequencing analyses to analyze the landscape of the TME modulated by TAMs in terms of a protumor microenvironment during early tumor development. Results: Our data revealed that the depletion of TAMs leads to a decreased epithelial-to-mesenchymal transition (EMT) signature in cancer cells and a distinct transcriptional state characterized by CD8+ T cell activation. Moreover, notable alterations in gene expression were observed upon the depletion of TAMs, identifying Galectin-1 (Gal-1) as a crucial molecular factor responsible for the observed effect. Gal-1 inhibition reversed immune suppression via the reinvigoration of CD8+ T cells, impairing tumor growth and potentiating immune checkpoint inhibitors in breast tumor models. Conclusion: These results provide comprehensive insights into TAM-mediated early tumor microenvironments and reveal immune evasion mechanisms that can be targeted by Gal-1 to induce antitumor immune responses.

Sexual dimorphism in cancer

The incidence and mortality of malignant neoplasms of non-reproductive organs both carcinomas and sarcomas in men is one and a half times higher than in women. This is based on genetic differences, which are superimposed by patterns of epigenetic regulation of the expression of sex chromosome genes that determine sex differences in the processes of tissue differentiation, which, in turn, mediates the formation of the hormonal status of the body. Compared to the Y chromosome, the mammalian X chromosome contains several dozen times more genes encoding major regulators of proliferation, metabolism, immunity, and tumor growth inhibitors, as well as X-linked microRNAs affecting transcription factors and cross-regulation by other non-coding RNAs. This results in a female or male gene expression profile that accounts for phenotypic differences. This peculiarity, along with the fact that in female cells on the second inactivatedX chromosome epigenetic repression of the most important genes is reversed and, accordingly, their expression level is doubled, may largely explain the sex disparity in carcinogenesis. The influence of sex hormones and disparity in the expression of antitumor immunity contribute significantly to this difference. A detailed study of the mechanisms underlying sex dimorphism in carcinogenesis will be an essential contribution to fundamental oncology and to the practice of diagnosis, prognosis and personalized treatment of malignances with regard to their gender-specific course. These studies are especially relevant in relation to insufficiently studied soft tissue sarcomas, the ratio of the frequencies of which in men and women varies greatly depending on the histological subtype of the tumor.

Multitargeting Prodrugs that Release Oxaliplatin, Doxorubicin and Gemcitabine are Potent Inhibitors of Tumor Growth and Effective Inducers of Immunogenic Cell Death.

A multitargeting prodrug (2) that releases gemcitabine, oxaliplatin, and doxorubicin in their active form in cancer cells is a potent cytotoxic agent with nM IC50s ; it is highly selective to cancer cells with mean selectivity indices to human (136) and murine (320) cancer cells. It effectively induces release of DAMPs (CALR, ATP & HMGB1) in CT26 cells facilitating more efficient phagocytosis by J774 macrophages than the FDA drugs or their co-administration. The viability of CT26 cells co-cultured with J774 macrophages and treated with 2 was reduced by 32 % compared to the non-treated cells, suggesting a synergistic antiproliferative effect between the chemical and immune reactions. 2 inhibited in vivo tumor growth in two murine models (LLC and CT26) better than the FDA drugs or their co-administration with significantly lower body weight loss. Mice inoculated with CT26 cells treated with 2 showed slightly better tumor free survival than doxorubicin.

Multitargeting Prodrugs that Release Oxaliplatin, Doxorubicin and Gemcitabine are Potent Inhibitors of Tumor Growth and Effective Inducers of Immunogenic Cell Death

AbstractA multitargeting prodrug (2) that releases gemcitabine, oxaliplatin, and doxorubicin in their active form in cancer cells is a potent cytotoxic agent with nM IC50s; it is highly selective to cancer cells with mean selectivity indices to human (136) and murine (320) cancer cells. It effectively induces release of DAMPs (CALR, ATP &amp; HMGB1) in CT26 cells facilitating more efficient phagocytosis by J774 macrophages than the FDA drugs or their co‐administration. The viability of CT26 cells co‐cultured with J774 macrophages and treated with 2 was reduced by 32 % compared to the non‐treated cells, suggesting a synergistic antiproliferative effect between the chemical and immune reactions. 2 inhibited in vivo tumor growth in two murine models (LLC and CT26) better than the FDA drugs or their co‐administration with significantly lower body weight loss. Mice inoculated with CT26 cells treated with 2 showed slightly better tumor free survival than doxorubicin.

The Impact of Pigment-Epithelium-Derived Factor on MCF-7 Cell Metabolism in the Context of Glycaemic Condition.

Studies have demonstrated that pigment-epithelium-derived factor (PEDF) is a robust inhibitor of tumour growth and development, implying that this may serve as a promising target for therapeutic intervention. However, the precise impact of PEDF on cancerous cell metabolic pathways remains uncertain despite ongoing research. In this light, this study aimed to employ a metabolomics approach for understanding the metabolic reprogramming events in breast cancer across different glycaemic loads and their response to PEDF. Gas chromatography-quadrupole mass spectrometry (GC/Q-MS) analysis revealed metabolic alterations in ER+ human cell line MCF-7 cells treated with PEDF under varying glycaemic conditions. The identification of significantly altered metabolites was accomplished through MetaboAnalyst (v.5.0) and R packages, which enabled both multivariate and univariate analyses. Out of the 48 metabolites identified, 14 were chosen based on their significant alterations in MCF-7 cells under different glycaemic conditions and PEDF treatment (p < 0.05, VIP > 0.8). Dysregulation in pathways associated with amino acid metabolism, intermediates of the TCA cycle, nucleotide metabolism, and lipid metabolism were detected, and they exhibited different responses to PEDF. Our results suggest that PEDF has a diverse influence on the metabolism of MCF-7 cells in both normo- and hyperglycaemic environments, thereby warranting studies using patient samples to correlate our findings with clinical response in the future.

Fibronectin fragments generated by pancreatic trypsin act as endogenous inhibitors of pancreatic tumor growth

BackgroundThe pancreatic microenvironment has a defensive role against cancer but it can acquire tumor-promoting properties triggered by multiple mechanisms including alterations in the equilibrium between proteases and their inhibitors. The identification of proteolytic events, targets and pathways would set the basis for the design of new therapeutic approaches.Methods and resultsHere we demonstrate that spheroids isolated from human and murine healthy pancreas and co-transplanted orthotopically with pancreatic ductal adenocarcinoma (PDAC) in mouse pancreas inhibited tumor growth. The effect was mediated by trypsin-generated fibronectin (FN) fragments released by pancreatic spheroids. Tumor inhibition was observed also in a model of acute pancreatitis associated with trypsin activation. Mass spectrometry proteomic analysis of fragments and mAb against different FN epitopes identified the FN type III domain as responsible for the activity. By inhibiting integrin α5β1, FAK and FGFR1 signaling, the fragments induced tumor cell detachment and reduced cell proliferation. Consistent with the mutual relationship between the two pathways, FGF2 restored both FGFR1 and FAK signaling and promoted PDAC cell adhesion and proliferation. FAK and FGFR inhibitors additively inhibited PDAC growth in vitro and in orthotopic in vivo models.ConclusionsThis study identifies a novel role for pancreatic trypsin and fibronectin cleavage as a mechanism of protection against cancer by the pancreatic microenvironment. The finding of a FAK-FGFR cross-talk in PDAC support the combination of FAK and FGFR inhibitors for PDAC treatment to emulate the protective effect of the normal pancreas against cancer.

DDQN-based optimal targeted therapy with reversible inhibitors to combat the Warburg effect

We cover the Warburg effect with a three-component evolutionary model, where each component represents a different metabolic strategy. In this context, a scenario involving cells expressing three different phenotypes is presented. One tumour phenotype exhibits glycolytic metabolism through glucose uptake and lactate secretion. Lactate is used by a second malignant phenotype to proliferate. The third phenotype represents healthy cells, which performs oxidative phosphorylation. The purpose of this model is to gain a better understanding of the metabolic alterations associated with the Warburg effect. It is suitable to reproduce some of the clinical trials obtained in colorectal cancer and other even more aggressive tumours. It shows that lactate is an indicator of poor prognosis, since it favours the setting of polymorphic tumour equilibria that complicates its treatment. This model is also used to train a reinforcement learning algorithm, known as Double Deep Q-networks, in order to provide the first optimal targeted therapy based on experimental tumour growth inhibitors as genistein and AR-C155858. Our in silico solution includes the optimal therapy for all the tumour state space and also ensures the best possible quality of life for the patients, by considering the duration of treatment, the use of low-dose medications and the existence of possible contraindications. Optimal therapies obtained with Double Deep Q-networks are validated with the solutions of the Hamilton–Jacobi–Bellman equation.

PHARMACOLOGICAL PROPERTIES OF PODOPHYLLUM HEXANDRUM ROYLE: A COMPREHENSIVE REVIEW

Podophyllum hexandrum Royle is an endemic and endangered valuable medicinal plantspeciescharacterisedasherbaceousandrhizomatousperennial.Thegeographicalpresence of Podophyllum hexandrum Royle spans over the Himalayas at an altitude rangingfrom 2000 to 4000 m above Mean Sea Level. With a long history of usage in traditionalmedicine, it has been exercised as an intestinal purgative, an inhibitor of tumour growth andasalvefornecroticandinfectedwounds.Manysecondarymetabolites,suchasPodophyllotoxin,havebeenreportedtobe extracted from the plant, which possessesanti-tumourpropertiestotreattesticularandlung cancer.TheextensiveexploitationofPodophyllumhexandrum Royle in regions of the Himalayashasledtoadeclineinthefrequencyofthespeciesinthepastfewyears.Thiscomprehensive review article aims to facilitate an updated overview of the pharmacologicalproperties of Podophyllum hexandrum Royle including its anti-cancer, anti-inflammatory,anti-microbial, anti-viral, anti-oxidant, and radio-protective effects. This article reviews themedicinal, phytochemical, pharmacological, ethnobotanical and cultivation-related aspects oftheplant.

Abstract 4999: Preclinical evaluation of MCLA-129, a bispecific antibody targeting EGFR and c-MET on solid tumor cells, in comparison with amivantamab

Abstract The HGF/c-MET pathway is frequently upregulated in tumors that are resistant to EGFR tyrosine kinase inhibitors. MCLA-129 is an antibody-dependent cellular cytotoxicity (ADCC) enhanced Biclonics® that targets epidermal growth factor receptor (EGFR) and c-MET in non-small cell lung cancer (NSCLC) and other solid tumors. MCLA-129 is a potent inhibitor of tumor growth applying various mechanisms of action (MOA), including inhibition of c-MET and EGFR signaling, antibody-dependent cellular phagocytosis (ADCP) and ADCC. Here we compared the MOA of MCLA-129 with the MOA of the EGFR-c-MET bispecific antibody amivantamab. The binding of MCLA-129 to tumor cells expressing different levels of EGFR and c-MET was quantified using radiolabeled antibodies. Scatchard plot analysis showed that the affinity of MCLA-129 for both c-MET and EGFR is in the low nanomolar range. In FACS, MCLA-129 and amivantamab show similar binding to tumor cells harboring EGFR or c-MET exon14-skipping mutations. Crossblock experiments with the c-MET binding antibody onartuzumab analog showed that MCLA-129 competes for the same HGF-binding region of c-MET, which is distinct from the binding site of amivantamab according to Neijssen et al, 2021 (PMC8113745). MCLA-129 and amivantamab did not downmodulate EGFR or c-MET. ADCP was also comparable for MCLA-129 and amivantamab, as measured with monocyte-derived macrophages incubated with pHrodo-labeled target cells with readout of tumor cell phagocytosis on the Incucyte® system. In contrast, MCLA-129 displayed ADCC activity similar to or more potently than amivantamab in an ADCC reporter assay with either high affinity FcγRIII 158V-variant or low affinity 158F-variant effector cells in absence or presence of soluble EGFR and soluble c-MET. MCLA-129-induced ADCC appears to be less affected than amivantimab by the presence of soluble EGFR and soluble c-MET. In conclusion, MCLA-129 is a Biclonics® common light chain bispecific antibody with multiple MOA including inhibition of c-MET and EGFR ligand binding, ADCP and ADCC comparable or more potent than amivantamab. A phase 1/2 clinical trial of MCLA-129 in solid tumors is ongoing. These data support the further clinical development of MCLA-129 in patients with NSCLC and other solid tumors. Citation Format: David J.J. de Gorter, Alexandre Deshiere, Arjen Kramer, Martijn van Rosmalen, Franziska Mortensen, Cecile Geuijen. Preclinical evaluation of MCLA-129, a bispecific antibody targeting EGFR and c-MET on solid tumor cells, in comparison with amivantamab. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 4999.

New in vitro findings about halogenated boroxine cytotoxicity and deregulation of cell death-related genes in GR-M melanoma cells.

Anti-proliferative effects of halogenated boroxine - K2(B3O3F4OH) (HB) - have been confirmed in multiple cancer cell lines, including melanoma, but the exact mechanism of action is still unknown. This study aimed to determine its cytotoxic effects on human Caucasian melanoma (GR-M) cell growth in vitro as well as on the expression of cell death-related genes BCL-2, BECN1, DRAM1, and SQSTM1. GR-M and peripheral blood mononuclear (PBM) cells were treated with different HB concentrations and their growth inhibition and relative gene expression profiles were determined using the Alamar blue assay and real-time PCR. HB significantly inhibited cell growth of both GR-M and PBM cells but was even more effective in GR-M melanoma cells, as significant inhibition occurred at a lower HB concentration of 0.2 mg/mL. GR-M BCL-2 expression was significantly downregulated (P=0.001) at HB concentration of 0.4 mg/mL, which suggests that HB is a potent tumour growth inhibitor. At the same time, it upregulated BCL-2 expression in normal (PBM) cells, probably by activating protective mechanisms against induced cytotoxicity. In addition, all but the lowest HB concentrations significantly upregulated SQSTM1 (P=0.001) in GR-M cells. Upregulated BECN1 expression suggests early activation of autophagy at the lowest HB concentration in SQSTM1 cells and at all HB concentrations in PBM cells. Our findings clearly show HB-associated cell death and, along with previous cytotoxicity studies, reveal its promising anti-tumour potential.

Synthesis and Structure-Activity Analysis of Icaritin Derivatives as Potential Tumor Growth Inhibitors of Hepatocellular Carcinoma Cells.

The prenylated flavonoid icaritin (ICT, 1), a new drug for treating advanced hepatocellular carcinoma (HCC), was selected as a template to develop more potent inhibitors. An initial semisynthetic modification of ICT was performed to obtain a structure-activity relationship (SAR), which indicated that the cytotoxicity is enhanced by OH-3 rhamnosylation and that OH-7 is an important modification site. Based on the results of the SAR study, 46 N-containing ICT derivatives were synthesized and evaluated as the anti-HCC inhibitors. The results showed that most of the derivatives produced inhibited three HCC cell lines used (Hep3B, HepG2 and SMMC-7721). The modification strategy was validated by 3D-QSAR, which provided information for the further design and optimization of ICT. The most potent compound, 11c, exhibited IC50 values of 7.6 and 3.1 μM against HepG2 and SMMC-7721 cells, respectively, which were more potent than those of ICT and sorafenib, respectively. Further mechanistic studies indicated that 11c caused arrest at the G0/G1 phase in the cell cycle and induced cell apoptosis in HepG2 and SMMC-7721 cells.

β-(4-fluorobenzyl) Arteannuin B induced interaction of ATF-4 and C/EBPβ mediates the transition of breast cancer cells from autophagy to senescence.

ATF-4 is a master regulator of transcription of genes essential for cellular-adaptive function. In response to the quantum and duration of stress, ATF-4 diligently responds to both pro-apoptotic and pro-survival signals converging into either autophagy or apoptosis/senescence. Despite emerging cues implying a relationship between autophagy and senescence, how these two processes are controlled remains unknown. Herein, we demonstrate β-(4-fluorobenzyl) Arteannuin B (here after Arteannuin 09), a novel semisynthetic derivative of Arteannuin B, as a potent ER stress inducer leading to the consistent activation of ATF-4. Persistent ATF-4 expression at early time-points facilitates the autophagy program and consequently by upregulating p21 at later time-points, the signaling is shifted towards G2/M cell cycle arrest. As bZIP transcription factors including ATF-4 are obligate dimers, and because ATF-4 homodimers are not highly stable, we hypothesized that ATF-4 may induce p21 expression by physically interacting with another bZIP family member i.e., C/EBPβ. Our co-immunoprecipitation and co-localization studies demonstrated that ATF-4 is principally responsible for the autophagic potential of Arteannuin 09, while as, induction of both ATF-4 and C/EBPβ is indispensable for the p21 regulated-cell cycle arrest. Interestingly, inhibition of autophagy signaling switches the fate of Arteannuin 09 treated cells from senescence to apoptosis. Lastly, our data accomplished that Arteannuin 09 is a potent inhibitor of tumor growth and inducer of premature senescence in vivo.

Loss of Expression of Antiangiogenic Protein FKBPL in Endometrioid Endometrial Carcinoma: Implications for Clinical Practice.

Background and Objectives: FK506 binding protein like (FKBPL) is a member of the immunophilin family, with anti-angiogenic effects capable of inhibiting the migration of endothelial cells and blood vessel formation. Its role as an inhibitor of tumor growth and angiogenesis has previously been shown in studies with breast and ovarian cancer. The role of FKBPL in angiogenesis, growth, and carcinogenesis of endometrioid endometrial carcinoma (EEC) is still largely unknown. The aim of this study was to examine the expression of FKBPL in EEC and benign endometrial hyperplasia (BEH) and its correlation with the expression of vascular endothelial factor-A (VEGF-A) and estrogen receptor alpha (ERα). Materials and Methods: Specimens from 89 patients with EEC and 40 patients with BEH, as well as histological, clinical, and demographic data, were obtained from the Clinical Hospital Centre Zemun, Belgrade, Serbia over a 10-year period (2010–2020). Immunohistochemical staining of the tissue was performed for FKBPL, VEGF-A, and ERα. Slides were analyzed blind by two pathologists, who measured the intensity of FKBPL and VEGF-A expression and used the Allred score to determine the level of ERα expression. Results: Immunohistochemical analysis showed moderate to high intensity of FKBPL expression in 97.5% (n = 39) of samples of BEH, and low or no expression in 93.3% (n = 83) of cases of EEC. FKBPL staining showed a high positive predictive value (98.8%) and a high negative predictive value for malignant diagnosis (86.7%). The difference in FKBPL expression between EEC and BEH was statistically significant (p < 0.001), showing a decrease in intensity and loss of expression in malignant tissues of the endometrium. FKBPL expression was positively correlated with ERα expression (intensity, percentage and high Allred score values) and negatively correlated with the expression of VEGF-A (p < 0.05 for all). Conclusions: FKBPL protein expression demonstrated a significant decrease in FKBPL in EEC in comparison to BEH tissue, with a high predictive value for malignancy. FKBPL might be emerging as a significant protein with antiangiogenic and antineoplastic effects, showing great promise for the diagnostic and therapeutic applications of its therapeutic derivatives in gynecological oncology.