Induction Of Apoptosis In Cancer Cells Research Articles

Stearoyl-CoA desaturase 1 inhibition induces ER stress-mediated apoptosis in ovarian cancer cells

Ovarian cancer is a leading cause of death among gynecologic tumors, often detected at advanced stages. Metabolic reprogramming and increased lipid biosynthesis are key factors driving cancer cell growth. Stearoyl-CoA desaturase 1 (SCD1) is a crucial enzyme involved in de novo lipid synthesis, producing mono-unsaturated fatty acids (MUFAs). Here, we aimed to investigate the expression and significance of SCD1 in epithelial ovarian cancer (EOC). Comparative analysis of normal ovarian surface epithelial (NOSE) tissues and cell lines revealed elevated SCD1 expression in EOC tissues and cells. Inhibition of SCD1 significantly reduced the proliferation of EOC cells and patient-derived organoids and induced apoptotic cell death. Interestingly, SCD1 inhibition did not affect the viability of non-cancer cells, indicating selective cytotoxicity against EOC cells. SCD1 inhibition on EOC cells induced endoplasmic reticulum (ER) stress by activating the unfolded protein response (UPR) sensors and resulted in apoptosis. The addition of exogenous oleic acid, a product of SCD1, rescued EOC cells from ER stress-mediated apoptosis induced by SCD1 inhibition, underscoring the importance of lipid desaturation for cancer cell survival. Taken together, our findings suggest that the inhibition of SCD1 is a promising biomarker as well as a novel therapeutic target for ovarian cancer by regulating ER stress and inducing cancer cell apoptosis.

Abstract 2103: Small extracellular vesicles derived from macrophages show anti-tumor effects in MDA-MB-231 cells

Abstract Triple-negative breast cancer is the primary cause of death in women globally due to the absence of targeted receptors on the tumor, making it hard to treat. In addition, the rapid spread of triple-negative breast cancer makes it difficult to manage using current treatment options such as lumpectomies, mastectomies, radiation, and chemotherapy. The survival rate for patients with triple-negative breast cancer is only 8-16%. Therefore, there is a critical need to develop new and effective treatment options. The objective of this study was to investigate the potential of M1 macrophage-derived exosomes to induce cancer cell apoptosis. To test this, we isolated M1 macrophage-derived exosomes to see their effects on triple-negative breast cancer MDA-MB-231 cells. We induce polarization in RAW 264.7 macrophage cells via lipopolysaccharide (LPS). Macrophage polarization was characterized using an enzyme-linked immunosorbent assay (ELISA), real-time PCR, nitric oxide production, and bright field microscopy. We characterized exosomes using nanoparticle tracking analysis (NTA) and scanning electron microscopy (SEM). The apoptosis marker, caspase 3/7 activation, was assessed using confocal microscopy in MDA-MB-231 cells. M1 macrophage-derived exosomes were isolated, characterized, and incubated with breast cancer cells to see their anticancer effects. Data showed the induction of apoptosis in 48 hours in triple-negative breast cancer cells. We conclude that exosomes derived from M1 macrophages may have the capability to induce apoptosis in triple-negative breast cancer. Citation Format: Parth Desai, Anjali Kumari, Saqer Al Abdullah, Kristen Dellinger. Small extracellular vesicles derived from macrophages show anti-tumor effects in MDA-MB-231 cells [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 2103.

Desirable L-asparaginases for treating cancer and current research trends.

Amino acid depletion therapy is a promising approach for cancer treatment. It exploits the differences in the metabolic processes between healthy and cancerous cells. Certain microbial enzymes induce cancer cell apoptosis by removing essential amino acids. L-asparaginase is an enzyme approved by the FDA for the treatment of acute lymphoblastic leukemia. The enzymes currently employed in clinics come from two different sources: Escherichia coli and Erwinia chrysanthemi. Nevertheless, the search for improved enzymes and other sources continues because of several factors, including immunogenicity, in vivo instability, and protease degradation. Before determining whether L-asparaginase is clinically useful, research should consider the Michaelis constant, turnover number, and maximal velocity. The identification of L-asparaginase from microbial sources has been the subject of various studies. The primary goals of this review are to explore the most current approaches used in the search for therapeutically useful L-asparaginases and to establish whether these investigations identified the crucial characteristics of L-asparaginases before declaring their therapeutic potential.

Structure-based approaches for the design of 6-aryl-1-(3,4,5-trimethoxyphenyl)-1H-benzo[d][1,2,3]triazoles as tubulin polymerization inhibitors

The colchicine binding site on tubulin has been widely acknowledged as an attractive target for anticancer drug exploitation. Here, we reported the structural optimization of the lead compound 4, which was proved in our previous work as a colchicine binding site inhibitor (CBSI). Based on docking researches for the active binding conformation of compound 4, a series of novel 6-aryl-1-(3,4,5-trimethoxyphenyl)-1H-benzo[d][1,2,3]triazole derivatives (9a–9x) were developed by replacing a CH group in the 1H-benzo[d]imidazole skeleton of compound 4 with a nitrogen atom as a hydrogen bond acceptor. Among them, compound 9a showed the strongest antiproliferative activity with IC50 values ranging from 14 to 45 nM against three human cancer cell lines (MCF-7, SGC-7901 and A549), lower than that of compound 4. Mechanistic studies indicated that compound 9a could inhibit tubulin polymerization, destroy the microtubule skeleton, block the cell cycle in G2/M phase, induce cancer cell apoptosis, prevent cancer cell migration and colony formation. Moreover, compound 9a significantly inhibited tumor growth in vivo without observable toxicity in the mice 4T1 xenograft tumor model. In conclusion, this report shows a successful case of the structure-based design approach of a potent tubulin polymerization inhibitor for cancer treatment.

Potent Apoptosis Induction by a Novel Trispecific B7-H3xCD16xTIGIT 2+1 Common Light Chain Natural Killer Cell Engager.

Valued for their ability to rapidly kill multiple tumor cells in succession as well as their favorable safety profile, NK cells are of increasing interest in the field of immunotherapy. As their cytotoxic activity is controlled by a complex network of activating and inhibiting receptors, they offer a wide range of possible antigens to modulate their function by antibodies. In this work, we utilized our established common light chain (cLC)-based yeast surface display (YSD) screening procedure to isolate novel B7-H3 and TIGIT binding monoclonal antibodies. The chicken-derived antibodies showed single- to low-double-digit nanomolar affinities and were combined with a previously published CD16-binding Fab in a 2+1 format to generate a potent NK engaging molecule. In a straightforward, easily adjustable apoptosis assay, the construct B7-H3xCD16xTIGIT showed potent apoptosis induction in cancer cells. These results showcase the potential of the TIGIT NK checkpoint in combination with activating receptors to achieve increased cytotoxic activity.

Structure-based discovery of potent CARM1 inhibitors for colorectal cancer therapy

Coactivator-associated arginine methyltransferase 1 (CARM1) plays an important role in cell proliferation and gene expression, and is highly expressed in a variety of tumor tissues. Guided by our previous reported structure of DCPR049_12, we focused on designing and evaluating selective CARM1 inhibitors, resulting in the identification of compound 11f as a promising lead candidate. Compound 11f displayed potent inhibition of CARM1 (IC50 = 9 nM). Comprehensive evaluations, including in vitro metabolic stability assessments, molecular modelling, cellular studies, and in vivo anti-tumor studies, confirmed that it induced cancer cell apoptosis and specifically inhibited CARM1's methylation function. Notably, compound 11f displayed significant anti-proliferative effects on colorectal cancer cell lines, showcasing its potential for targeted therapies against CARM1-related diseases. This study provides valuable insights for the future development of specific and effective CARM1 inhibitors.

Black phosphorus-based nanoparticles induce liver cancer cell mitochondrial apoptosis and immune cell tumor infiltration for enhancing dendritic cell therapy

Cellular immunotherapy is a crucial aspect of current tumor immunotherapy, though it presents several challenges such as immune cell dysfunction, limited recognition of neoantigens, and inadequate lymphocyte infiltration into the tumor microenvironment. This study proposes a novel approach utilizing a combination of dendritic cell (DC)-based cellular immunotherapy and a photothermal nanoadjuvant black phosphorus (BP) nanoparticles to overcome these challenges. A new platform called PLGA@BP-R848, which consists of modifying poly-(lactic-co-glycolic acid) (PLGA) onto BP nanosheets loading the immune adjuvant R848. The PLGA@BP-R848 nanoparticles demonstrated exceptional drug delivery and release capabilities, as well as a photothermal effect, biocompatibility, and the ability to activate the mitochondrial apoptotic pathway Blc-2-Bax-Cytochrome c-caspase-3 and inhibit the PI3K-AKT-mTOR signaling pathway. In a hepatocellular carcinoma mouse model, the binding of PLGA@BP-R848 nanoparticles and dendritic cells primed with GPC3 peptides, successfully induced a systemic anti-tumor immune response. PLGA@BP-R848 nanoparticles bolster immune cell infiltration into tumors and induce cancer cell apoptosis. The synergistic therapy involving dendritic cells and photothermal nanoadjuvant effectively suppressed tumor growth, and facilitated the formation of tertiary lymphatic structures (TLS) in tumors. This study presents a novel approach in using photothermal nanoadjuvants to advance antitumor effect of cellular immunotherapy, such as DCs therapy.

Enhanced Anti-tumor Effect of Flavopiridol in Combination With Gemcitabine in Pancreatic Cancer.

The efficacy of current chemotherapies for pancreatic ductal adenocarcinoma (PDAC) is still unsatisfactory. Flavopiridol inhibits multiple cyclin-dependent kinases, causing cell cycle arrest and inducing cancer cell apoptosis. This study aimed to evaluate the anti-tumor effect of flavopiridol and gemcitabine in PDAC in vitro and in vivo. PANC-1 and MIA PaCa-2 cell lines were treated with gemcitabine and flavopiridol alone, in combination, and sequentially, and cell proliferation, apoptosis, and the cell cycle were evaluated. Proteins related to cell cycle progression (cyclin A, CDK2, E2F-1, and p53) were quantified using western blotting. A xenograft mouse model was generated, and the effects of gemcitabine and flavopiridol, administered alone or in combination, were evaluated by measuring tumor volume and apoptosis degree using the TUNEL assay. Sequential administration of gemcitabine and flavopiridol suppressed PDAC cell proliferation and induced apoptosis. Flavopiridol treatment led to an increase in the number of cells in the S and a decrease in those in the G0/G1 phases. Gemcitabine increased and decreased the number of S- and G2/M-phase cells, respectively. Furthermore, flavopiridol treatment decreased cyclin A and CDK2 expression and increased E2F-1 expression. In a xenograft mouse model, the combined administration of gemcitabine and flavopiridol demonstrated the most significant reduction in tumor volume and induction of apoptosis. Flavopiridol potentiates the anti-tumor activity of gemcitabine by inducing cell cycle arrest and apoptosis. Its synergistic inhibition of PDAC cell proliferation, when combined with gemcitabine, positions flavopiridol as a promising candidate for cancer treatment.

Cyanidin-3-O-Glucoside Combined with PGC1α Inhibitor Promotes Cancer Cell Death by Inducing Excessive Levels of ROS in Cervical Squamous Cell Carcinoma

Cervical cancer is a global public health problem, particularly in the low-income and middle-income countries. Natural products, such as cyanidin and its derivative cyanidin-3-O-glucoside (C3G), are considered safe and nontoxic food additives, potent therapeutic options for cancer. The present study aims to evaluate the beneficial effects of C3G on cervical squamous cell carcinoma (CSCC) in vitro and explore more potential therapeutic strategies for CSCC. C3G significantly inhibited the cell growth of CSCC cells and induced cancer cell apoptosis in a dose-dependent manner. Meanwhile, C3G promoted cellular reactive oxygen species (ROS) accumulation and decreased mitochondrial membrane potential and mitochondrial mass. The antioxidant regent N-acetyl-L-cysteine (NAC) rescued the effect of C3G on CSCC cells, further demonstrating ROS’s important role in C3G treatment. To explore the underlying mechanism, autophagy-related signaling pathways were investigated, and the results showed that C3G induced cell autophagy but not mitophagy. More importantly, C3G caused a significant activation of mitochondria biogenesis through the peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC-1α) signaling pathway. C3G synergized with PGC-1α inhibitor SR-18292 induced more severe ROS accumulation and showed more potent inhibition of cell proliferation and mitochondrial membrane potential than C3G treatment alone. Thus, the present study suggests a new potential therapeutic strategy for CSCC based on the synergistic effect of C3G and PGC1α inhibitors.

Molecular Motor-Driven Light-Controlled Logic-Gated K+ Channel for Cancer Cell Apoptosis.

Developing artificial ion transport systems, which process complicated information and step-wise regulate properties, is essential for deeply comprehending the subtle dynamic behaviors of natural channel proteins (NCPs). Here a photo-controlled logic-gated K+ channel based on single-chain random heteropolymers containing molecular motors, exhibiting multi-core processor-like properties to step-wise control ion transport is reported. Designed with oxygen, deoxygenation, and different wavelengths of light as input signals, complicated logical circuits comprising "YES", "AND", "OR" and "NOT" gate components are established. Implementing these logical circuits with K+ transport efficiencies as output signals, multiple state transitions including "ON", "Partially OFF" and "Totally OFF" in liposomes and cancer cells are realized, further causing step-wise anticancer treatments. Dramatic K+ efflux in the "ON" state (decrease by 50% within 7min) significantly induces cancer cell apoptosis. This integrated logic-gated strategy will be expanded toward understanding the delicate mechanism underlying NCPs and treating cancer or other diseases is expected.

Rapamycin as a Potential Alternative Drug for Squamous Cell Gingiva Carcinoma (Ca9-22): A Focus on Cell Cycle, Apoptosis and Autophagy Genetic Profile.

Oral cancer is considered as one of the most common malignancies worldwide. Its conventional treatment primarily involves surgery with or without postoperative adjuvant therapy. The targeting of signaling pathways implicated in tumorigenesis is becoming increasingly prevalent in the development of new anticancer drug candidates. Based on our recently published data, Rapamycin, an inhibitor of the mTOR pathway, exhibits selective antitumor activity in oral cancer by inhibiting cell proliferation and inducing cancer cell apoptosis, autophagy, and cellular stress. In the present study, our focus is on elucidating the genetic determinants of Rapamycin's action and the interaction networks accountable for tumorigenesis suppression. To achieve this, gingival carcinoma cell lines (Ca9-22) were exposed to Rapamycin at IC50 (10 µM) for 24 h. Subsequently, we investigated the genetic profiles related to the cell cycle, apoptosis, and autophagy, as well as gene-gene interactions, using QPCR arrays and the Gene MANIA website. Overall, our results showed that Rapamycin at 10 µM significantly inhibits the growth of Ca9-22 cells after 24 h of treatment by around 50% by suppression of key modulators in the G2/M transition, namely, Survivin and CDK5RAP1. The combination of Rapamycin with Cisplatin potentializes the inhibition of Ca9-22 cell proliferation. A P1/Annexin-V assay was performed to evaluate the effect of Rapamycin on cell apoptosis. The results obtained confirm our previous findings in which Rapamycin at 10 μM induces a strong apoptosis of Ca9-22 cells. The live cells decreased, and the late apoptotic cells increased when the cells were treated by Rapamycin. To identify the genes responsible for cell apoptosis induced by Rapamycin, we performed the RT2 Profiler PCR Arrays for 84 apoptotic genes. The blocked cells were believed to be directed towards cell death, confirmed by the downregulation of apoptosis inhibitors involved in both the extrinsic and intrinsic pathways, including BIRC5, BNIP3, CD40LG, DAPK1, LTA, TNFRSF21 and TP73. The observed effects of Rapamycin on tumor suppression are likely to involve the autophagy process, evidenced by the inhibition of autophagy modulators (TGFβ1, RGS19 and AKT1), autophagosome biogenesis components (AMBRA1, ATG9B and TMEM74) and autophagy byproducts (APP). Identifying gene-gene interaction (GGI) networks provided a comprehensive view of the drug's mechanism and connected the studied tumorigenesis processes to potential functional interactions of various kinds (physical interaction, co-expression, genetic interactions etc.). In conclusion, Rapamycin shows promise as a clinical agent for managing Ca9-22 gingiva carcinoma cells.

Synthesis of asymmetric cationic zinc porphyrin photosensitizer containing thiophene group for photodynamic therapy in vitro and theoretical calculation of DFT

Porphyrins, as photosensitizers for photodynamic therapy, is used to treat various cancers. In this study, three different side-chain variants of thiophene-zinc porphyrins were synthesized (Zn-P1, Zn-P2, and Zn-P3). Among the synthesized compounds, Zn-P1 exhibited the highest activity and demonstrated superior singlet oxygen generation capability according to both density functional theory calculations and singlet oxygen generation experiments. Our cytotoxicity assays revealed that Zn-P1 exhibited remarkable phototoxicity along with a pronounced selectivity for HepG2 cells. This selectivity was confirmed by cell staining experiments, which showed obvious apoptotic processes. Further insight into this anticancer mechanism was provided by cell reactive oxygen species experiments, which explained the induction of cancer cell apoptosis. Light-activated production of reactive oxygen species by photosensitizers initiates the apoptotic cascade in cancer cells. This study highlights the utility of cationic porphyrin photosensitizer complexes in photodynamic therapy and provides new insights for the development of innovative photosensitizers in cancer treatment.

Degradation of AZGP1 suppresses apoptosis and facilitates cholangiocarcinoma tumorigenesis via TRIM25.

Alpha-2-Glycoprotein 1, Zinc-binding (AZGP1, ZAG) is a secreted protein that is synthesized by adipocytes and epithelial cells; it is downregulated in several malignancies such as breast, prostate, liver and lung cancers. However, its function remains unclear in cholangiocarcinoma (CCA). Here, we evaluated the impact AZGP1 in CCA using Gene Expression Omnibus (GEO) and GEPIA. In addition, we analysed AZGP1 expression using quantitative reverse transcription PCR and western blotting. Expression of AZGP1 was nearly deficient in CCA patients and cell lines and was associated with poor prognosis. AZGP1 overexpression upregulated apoptosis markers. Co-immunoprecipitation experiments showed that AZGP1 interacts with tripartite motif-containing protein 25 (TRIM25), and tissue microarray and bioinformatic analysis showed that AZGP1 is negatively correlated with TRIM25 expression in CCA. Thereafter, TRIM25 knockdown led to AZGP1 upregulation and induced cancer cell apoptosis. TRIM25 targets AZGP1 for degradation by catalysing its ubiquitination. AZGP1 overexpression significantly suppressed tumour growth in a xenograft mouse model. This study findings suggest that AZGP1 is a potential therapeutic target or a diagnostic biomarker for treating patients with CCA.

Multimodal Golden DNA Superstructures (GDSs) for Highly Efficient Photothermal Immunotherapy.

DNA-templated metallization has emerged as an efficient strategy for creating nanoscale-metal DNA hybrid structures with a desirable conformation and function. Despite the potential of DNA-metal hybrids, their use as combinatory therapeutic agents has rarely been examined. Herein, we present a simple approach for fabricating a multipurpose DNA superstructure that serves as an efficient photoimmunotherapy agent. Specifically, we adsorb and locally concentrate Au ions onto DNA superstructures through induced local reduction, resulting in the formation of Au nanoclusters. The mechanical and optical properties of these metallic nanoclusters can be rationally controlled by their conformations and metal ions. The resulting golden DNA superstructures (GDSs) exhibit significant photothermal effects that induce cancer cell apoptosis. When sequence-specific immunostimulatory effects of DNA are combined, GDSs provide a synergistic effect to eradicate cancer and inhibit metastasis, demonstrating potential as a combinatory therapeutic agent for tumor treatment. Altogether, the DNA superstructure-templated metal casting system offers promising materials for future biomedical applications.

Modification of a natural diterpene and its antitumor mechanism: Promoting apoptosis, suppressing migration, and inhibiting angiogenesis

The synthesis or derivation of a series of structural analogues based on natural products is a common strategy for discovering antitumor drugs. As a unique natural diterpene derived from Trigonostemon howii, 3,4-seco-sonderianol (1) exhibited moderate cytotoxic effects. To improve the activity, a new diterpene derivative (1b) with a mitochondrial targeting function was synthesized by coupling triphenylphosphine to compound 1. Compared to the parent molecule, the antitumor activity of 1b increased greatly. A series of mechanistic experiments revealed that compound 1b induced cancer cell apoptosis and inhibited cancer cell migration by targeting the mitochondria and regulating the STAT3 and FAK signaling pathways. Meanwhile, 1b was found to inhibit angiogenesis in a transgenic zebrafish model. It is worth noting that 1b also demonstrated excellent antitumor effects in zebrafish tumor xenotransplantation models. All the evidence supports that compound 1b targeting mitochondria has the potential to be a candidate for an antitumor drug.

Investigating the potential of zinc oxide nanoparticles and zinc ions as promising approaches to lung cancer

Lung cancer is the leading cause of cancer casualties globally, with adverse side effects and drug resistance making current therapeutic options inadequate. Therefore, novel therapeutics require development. A major genetic contributor to these cancers is the mutant TP53 gene, whose mutated protein fails to transactivate p21, a cell cycle control protein in p53-p21-RB signaling, resulting in uncontrolled cell growth and cisplatin resistance. Recent studies suggest zinc oxide nanoparticles (ZnO NPs) show promise as a targeted, cytotoxic therapy; however, their mechanisms and efficacy are strongly debated as they aggregate in solution, reducing bioavailability while demonstrating poor aqueous solubility. As such, we hypothesized that a combined treatment using either ZnO NPs and cisplatin or zinc ions and cisplatin would induce cancer cell apoptosis and reduce cisplatin resistance. We treated mutant p53 lung cancer cells with ZnO NPs, zinc ion solution isolated from the NP suspension, and/or cisplatin; all significantly reduced proliferation individually and in combination. Increased reactive oxygen species (ROS) and p21 upregulation from ZnO NP treatment suggests mechanisms involving p21, perhaps through a p53-independent mechanism or via p53 reactivation. Zinc ion solution rendered a reduction in p21 in the presence of significantly lower ROS induced by ZnO NP, suggesting a mechanism needing further elucidation. We subjected a control cell line, HaCaT cells, to the same treatments and demonstrated no significant reduction in proliferation in the presence of ZnO NPs or zinc ions. Our research suggests the use of ZnO NPs and zinc ions as potential strategies for lung cancer treatment regimens.

Acid-assisted self-assembly of pyrene-capped tyrosine ruptures lysosomes to induce cancer cell apoptosis.

Induced lysosomal membrane permeabilization (LMP) by peptide self-assembly has emerged as an effective platform for lysosome-targeted cancer therapy. In this study, we shift this strategical paradigm and present an innovative approach to LMP induction through amino acid-based self-assembly. Pyrene-capped tyrosine (Py-Tyr), as a proof-of-concept molecule, is designed with acidity-responsive self-assembly. Under acidic conditions (pH 4), Py-Tyr is protonated with reduced charge repulsion, and self-assembles into micrometer-scaled aggregates, which exceed the biological size of lysosomes. Cell experiments showed that Py-Tyr specifically accumulates in lysosomes and induces lysosome rupture, leading to the release of cathepsin B into the cytoplasm for subsequent apoptosis activation in cancer cells. This study capitalizes on the concept of amino acid assembly for efficient LMP induction, providing a simple and versatile platform for precise and effective therapeutic interventions in cancer therapy.

Tumor Microenvironment-Activated Nanostructure to Enhance MRI Capability and Nanozyme Activity for Highly Tumor-Specific Multimodal Theranostics.

Copper-based nanozymes exhibit excellent antitumor activity but are easily inactivated due to the disturbance of proteins or other macromolecules with sulfhydryl. A tumor microenvironment-responsive CuMnO@Fe3O4 (CMF) core-shell nanozyme for highly efficient tumor theranostics is developed. A platelet-derived growth factor receptor-β-recognizing cyclic peptide (PDGFB) target is conjugated to the surface of CMF to fabricate a tumor-specific nanozyme (PCMF). The core-shell nanostructure significantly avoids the oxidation and inactivation of copper-based nanozyme, promoting the antitumor activity of PCMF. The weak acid- and GSH-activated T1 and T2 relaxation rate of PCMF contributes to T1 and T2 dual contrast imaging at the tumor site. In addition, the PCMF disintegrates and produces some metal ions that possess Fenton catalytic activity (i.e., Cu+, Mn2+, and Fe2+) under TME. This process significantly depletes GSH, accelerates Fenton and Fenton-like reactions, enhances cellular reactive oxygen species (ROS) levels, and induces cancer cell apoptosis and ferroptosis. PCMF also exhibits photothermal functions, so it can be used in combined photothermal therapy, ferroptosis therapy, and chemodynamic therapy, improving anticancer activity. This work provides insights into the design of an exquisite nanostructure for high-sensitive and tumor-specific theranostics.

Design, synthesis and biological evaluation of potent epidermal growth factor receptor tyrosine kinase (EGFR-TK) inhibitors against resistance mutation for lung cancer treatment

In this study, we identified a newly synthesized compound 7o with potent inhibition on EGFR primary mutants (L858R, Del19) and drug-resistant mutant T790M with nanomolar IC50 values. 7o showed strong antiproliferative effects against EGFR mutant-driven non-small cell lung cancer (NSCLC) cells such as H1975, PC-9 and HCC827, over cells expressing EGFRWT. Molecular docking was performed to investigate the possible binding modes of 7o inside the binding site of EGFRL858R/T790M and EGFRWT. Analysis of cell cycle evidenced that 7o induced cell cycle arrest in G1 phases in the EGFR mutant cells, H1975 and PC-9, which resulted in decreased S-phase populations. Moreover, compound 7o induced cancer cell apoptosis in in vitro assays. In addition, 7o inhibited cellular phosphorylation of EGFR. In vivo, oral administration of 7o caused rapid tumor regression in H1975 xenograft model. Therefore, 7o might deserve further optimization as cancer treatment agent for EGFR mutant-driven NSCLC.

Abstract B034: A phase 2 basket study of the oral MDM2 inhibitor milademetan for MDM2-amplified advanced solid tumors (MANTRA-2)

Abstract Milademetan is an oral, selective, small molecular inhibitor of the MDM2-p53 complex that reactivates p53 to induce cancer cell apoptosis and tumor regressions in nonclinical models. Clinically, MDM2 gene amplification (amp) occurs in 1–2% of advanced solid tumors and is associated with a poor prognosis. Preliminary antitumor activity was seen in patients with MDM2 amp and TP53 wild-type (WT) tumors in a phase 1 clinical trial [Tirunagaru et al. AACR-NCI-EORTC 2021]. We conducted a phase 2 basket study to evaluate the efficacy of milademetan in patients with advanced or metastatic solid tumors (except liposarcoma, intimal sarcoma, and primary CNS tumors) with MDM2 copy number (CN) ≥8 and WT TP53 status based on local next-generation sequencing (NGS) (NCT05012397). Milademetan was administered at 260 mg on days 1–3 and 15–17 of a 28-day cycle. Tumor assessments were performed every 8 weeks (RECIST v1.1). MDM2 CN was retrospectively analyzed centrally using a commercial NGS assay, which also allowed correlation with other co-occurring alterations. As of June 23, 2023, 39 patients were enrolled with 13 distinct tumor types. The most common histologies were biliary tract cancers (8, 20.5%), sarcomas (7, 17.9%), and breast cancer (6, 15.3%). Median number of prior systemic therapies was 3 (range 0–12). Thirty-eight patients were evaluable for safety. The most common hematologic grade 3/4 adverse events (AEs) related to milademetan were thrombocytopenia (26.3%), neutropenia (15.8%), and anemia (10.5%). All grade treatment-related AEs (>15% incidence) included thrombocytopenia (44.7%), nausea (42.1%), fatigue (36.8%), vomiting (31.6%), anemia (23.7%), diarrhea (23.7%) and neutropenia (18.4%). No bleeding or neutropenic sepsis events were reported, and no grade 5 events were observed. The dose reduction rate was 13.2%, and 7.9% of patients discontinued milademetan due to AEs. Central tumor testing was available on 30 (76.9%) patients and only 2 (6.7%) patients demonstrated MDM2 CN below the threshold of 8. Thirty-two patients were efficacy evaluable and had confirmed CN ≥8 or pending central analysis. Five partial responses (15.6%) were observed (4 unconfirmed, 1 confirmed) with one each in lung adenocarcinoma (co-alteration of EGFR + KRAS), pancreatic (KRAS), bladder (pending), gastric cancer (DNAB1-PRKACA) and endometrial sarcoma (CCND2). No clear correlation between MDM2 CN and tumor regression was observed. The median progression-free survival was 3.3 months (95% CI, 2.5–6.1). The longest patient on milademetan therapy was 41 weeks (biliary, best RECIST 1.1 response SD with –29% tumor reduction). Ten patients are currently ongoing. Milademetan monotherapy demonstrated clinically meaningful antitumor responses with a manageable toxicity profile in a variety of MDM2 amp, TP53 WT solid tumors, including those with other oncogenic drivers such as KRAS. Rational combination strategies with milademetan should be considered in tumors with WT TP53 to further enhance durable anti-tumor activity. Citation Format: Ecaterina E. Dumbrava, Christopher T. Chen, Gregory M. Cote, Glenn J. Hanna, Thomas E. Stinchcombe, Bradley Sumrall, Trisha Wise-Draper, Mohammed Kanaan, Steven Duffy, Christopher Sumey, Patrick Cobb, Naisargee Shah, Bo Zhang, Nora Ku, Robert C. Doebele, Mrinal Gounder. A phase 2 basket study of the oral MDM2 inhibitor milademetan for MDM2-amplified advanced solid tumors (MANTRA-2) [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2023 Oct 11-15; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2023;22(12 Suppl):Abstract nr B034.