Development Of Cancer Therapeutics Research Articles

Chemical characterization and cytotoxic effect of three edible fungi (Morchella) against breast cancer cells: A therapeutic approach

Current breast cancer therapeutics are associated with short-term efficacy, increased drug resistance, and severe adverse reactions, thus demanding the development of new therapeutic approaches. This present study aimed to explore the cytotoxic activity of Morchella extracts in the context of the MCF-7 cell line (breast cancer) and ultra-performance liquid chromatography mass spectroscopy (UPLC-MS) analysis. The cytotoxic activity of the Morchella conica, Morchella delicosa, and Morchella escuelnta extracts was examined against the breast cancer cell line (MCF-7), using a 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide) assay (MTT assay). The Morchella extracts were screened for the presence of compounds using ultra-performance liquid chromatography mass spectroscopy (UPLC-MS/MS) based analysis. All the Morchella extracts actively restricted the viability and proliferation of breast cancer cells in a dose-dependent manner, with half maximal inhibitory concentration (IC50) values ranging from 0.017 to 0.68 mg/ml. The main compounds identified in Morchella include alkaloid, sterol, flavonoid, terpenoid, fatty acid, peptide, glutamic acid, amino acid, coumarin, and cyclopyrrolone. In conclusion, Morchella extracts exhibited cytotoxic effects against breast cancer cell lines and decreased the viability of MCF-7 cell line. The Morchella compounds might be the main components contributing to the inhibition of breast cancer cells. The findings of this research offer an innovative framework for advanced investigations for the development of cancer therapeutics from this fungus.

Mechanistic insights into xanthomicrol as the active anti-HCC ingredient of Phytolacca acinosa Roxb.: A network pharmacology analysis and transcriptomics integrated experimental verification

Ethnopharmacological relevancePhytolacca acinosa Roxb. (PAR) is a Traditional Chinese Medicinal (TCM) plant with a broad global distribution encompassing 35 species, four of which are found in the People's Republic of China. It occupies a significant role in both Oriental and American traditional medicine, employed in treating a range of conditions such as edema, inflammation, dermatitis, and rheumatism. PAR is also used as a molluscicide and for addressing tumors and bronchitis. The plant is documented in the Chinese Pharmacopoeia and has a longstanding history in TCM, particularly for its diuretic properties and in treating ailments such as edema, swelling, and ulcers. Notably, PAR has demonstrated potent inhibitory effects against the A549 human lung cancer cell line, underscoring its potential in contributing to the development of novel cancer therapeutics. Aim of the studyThe research aims to elucidate the active components of PAR and their mechanisms in treating hepatocellular carcinoma (HCC). Materials and methodsEmploying network pharmacology, this study predicted the principal active compounds and key targets of PAR. A holistic methodology incorporating biological network analysis, transcriptomics sequencing, molecular docking, and molecular dynamics (MD) simulations was utilized to forecast the effects of PAR on HCC, with empirical evidence supporting these findings. ResultsNetwork pharmacology identified xanthomicrol as the foremost active compound in PAR. The tumor-suppressive functions of PAR, as indicated by KEGG pathway analysis and transcriptomics sequencing, predominantly occur via the PI3K/AKT pathway. Molecular docking and dynamics simulations demonstrated the high affinity of xanthomicrol towards TNF, MMP9, PPARG, KDR, and MMP2. In vivo experiments verified the efficacy of xanthomicrol in curtailing HCC tumor growth, while in vitro assessments revealed its substantial impact on the proliferation and apoptosis of HepG2 and HCCLM3 cells. Moreover, the study indicates that xanthomicrol may modulate the expression of TNF, MMP9, PPARG, KDR, and MMP2 in HCC cells and inhibit the activation of the PI3K/AKT pathway. ConclusionsXanthomicrol, a principal active component of PAR, has been identified to impede the growth of HCC by targeting the PI3K/Akt/MMP9 pathway. This insight could enhance therapeutic approaches for HCC.

LAPTM4B counteracts ferroptosis via suppressing the ubiquitin-proteasome degradation of SLC7A11 in non-small cell lung cancer

Non-small cell lung cancer (NSCLC) is a leading cause of cancer-related deaths worldwide, necessitating the identification of novel therapeutic targets. Lysosome Associated Protein Transmembrane 4B (LAPTM4B) is involved in biological processes critical to cancer progression, such as regulation of solute carrier transporter proteins and metabolic pathways, including mTORC1. However, the metabolic processes governed by LAPTM4B and its role in oncogenesis remain unknown. In this study, we conducted unbiased metabolomic screens to uncover the metabolic landscape regulated by LAPTM4B. We observed common metabolic changes in several knockout cell models suggesting of a role for LAPTM4B in suppressing ferroptosis. Through a series of cell-based assays and animal experiments, we demonstrate that LAPTM4B protects tumor cells from erastin-induced ferroptosis both in vitro and in vivo. Mechanistically, LAPTM4B suppresses ferroptosis by inhibiting NEDD4L/ZRANB1 mediated ubiquitination and subsequent proteasomal degradation of the cystine-glutamate antiporter SLC7A11. Furthermore, metabolomic profiling of cancer cells revealed that LAPTM4B knockout leads to a significant enrichment of ferroptosis and associated metabolic alterations. By integrating results from cellular assays, patient tissue samples, an animal model, and cancer databases, this study highlights the clinical relevance of the LAPTM4B-SLC7A11-ferroptosis signaling axis in NSCLC progression and identifies it as a potential target for the development of cancer therapeutics.

Engineered cell versus modified exosomes in cancer therapy

AbstractCancer therapeutic development is the most challenging domain in cancer. Cell‐based cancer therapeutics come up with promising effectiveness. This approach was also cell‐modified for better targeting efficiency development. Cell engineering‐based cancer therapeutic is a cutting‐edge method in cancer therapy. Due to complications of this process, cost and post‐treatment side effects, this phenomenon came into the question mark. In this scenario, extracellular vesicle (EVs) research introduces a cell‐free cancer therapeutic approach. In the therapeutic aspect most used EVs, come from stem cells, plants, and engineered cells. Among several EVs populations, Exosomes are the most used worldwide cell‐free therapeutic tool for ageing cancer. The most interesting facts about exosomes are the biocompatible, non‐immunoreactive, cross‐biological barrier, and non‐toxic (depending on the parental cell's nature). In this article, we are exploring modified exosomes (biological or chemical) that create a remarkable outcome in cancer therapeutic development compared to engineered cell‐based therapeutics. Hope, in the future, modified exosomes become an effective, affordable, and specific cancer‐targeting precision medicine.

Structural basis for the bi-specificity of USP25 and USP28 inhibitors

The development of cancer therapeutics is often hindered by the fact that specific oncogenes cannot be directly pharmaceutically addressed. Targeting deubiquitylases that stabilize these oncogenes provides a promising alternative. USP28 and USP25 have been identified as such target deubiquitylases, and several small-molecule inhibitors indiscriminately inhibiting both enzymes have been developed. To obtain insights into their mode of inhibition, we structurally and functionally characterized USP28 in the presence of the three different inhibitors AZ1, Vismodegib and FT206. The compounds bind into a common pocket acting as a molecular sink. Our analysis provides an explanation why the two enzymes are inhibited with similar potency while other deubiquitylases are not affected. Furthermore, a key glutamate residue at position 366/373 in USP28/USP25 plays a central structural role for pocket stability and thereby for inhibition and activity. Obstructing the inhibitor-binding pocket by mutation of this glutamate may provide a tool to accelerate future drug development efforts for selective inhibitors of either USP28 or USP25 targeting distinct binding pockets.

Preclinical models of bladder cancer: BBN and beyond.

Preclinical modelling is a crucial component of advancing the understanding of cancer biology and therapeutic development. Several models exist for understanding the pathobiology of bladder cancer and evaluating therapeutics. N-butyl-N-(4-hydroxybutyl)-nitrosamine (BBN)-induced bladder cancer is a commonly used model that recapitulates many of the features of human disease. Particularly in mice, BBN is a preferred laboratory model owing to a high level of reproducibility, high genetic fidelity to the human condition, and its relative ease of use. However, important aspects of the model are often overlooked in laboratory studies. Moreover, the advent of new models has yielded a variety of methodologies that complement the use of BBN. Toxicokinetics, histopathology, molecular genetics and sex can differ between available models and are important factors to consider in bladder cancer modelling.

Oxidative stress in peroxisomes induced by androgen receptor inhibition through peroxisome proliferator–activated receptor promotes enzalutamide resistance in prostate cancer

Androgen receptor (AR)-targeting therapy induces oxidative stress in prostate cancer. However, the mechanism of oxidative stress induction by AR-targeting therapy remains unclear. This study investigated the mechanism of oxidative stress induction by AR-targeting therapy, with the aim to develop novel therapeutics targeting oxidative stress induced by AR-targeting therapy. Intracellular reactive oxygen species (ROS) was examined by fluorescence microscopy and flow cytometry analysis. The effects of silencing gene expression and small molecule inhibitors on gene expression and cytotoxic effects were examined by quantitative real-time PCR and cell proliferation assay. ROS induced by androgen depletion co-localized with peroxisomes in prostate cancer cells. Among peroxisome-related genes, PPARA was commonly induced by AR inhibition and involved in ROS production via PKC signaling. Inhibition of PPARα by specific siRNA and a small molecule inhibitor suppressed cell proliferation and increased cellular sensitivity to the antiandrogen enzalutamide in prostate cancer cells. This study revealed a novel pathway by which AR inhibition induced intracellular ROS mainly in peroxisomes through PPARα activation in prostate cancer. This pathway is a promising target for the development of novel therapeutics for prostate cancer in combination with AR-targeting therapy such as antiandrogen enzalutamide.

TRPV1-Dependent Antiproliferative Activity of Dioecious Maclura pomifera Extracts in Estrogen Receptor-Positive Breast Cancer Cell Lines Involves Multiple Apoptotic Pathways.

Globally, breast cancer is a significant cause of mortality. Recent research focused on identifying compounds regulating the transient receptor potential vanilloid 1 (TRPV1) ion channel activity for the possibility of developing cancer therapeutics. In this study, the antiproliferative properties and mechanisms of action through TRPV1 of Maclura pomifera, a dioecious tree native to the south-central USA, have been investigated. Male and female extracts of spring branch tissues and leaves (500 µg/mL) significantly reduced the viability of MCF-7 and T47D cells by 75-80%. M. pomifera extracts induced apoptosis by triggering intracellular calcium overload via TRPV1. Blocking TRPV1 with the capsazepine antagonist and pretreating cells with the BAPTA-AM chelator boosted cell viability, revealing that M. pomifera phytochemicals activate TRPV1. Both male and female M. pomifera extracts initiated apoptosis through multiple pathways, the mitochondrial, ERK-induced, and endoplasmic reticulum-stress-mediated apoptotic pathways, demonstrated by the expression of activated caspase 3, caspase 9, caspase 8, FADD, FAS, ATF4, and CHOP, the overexpression of phosphorylated PERK and ERK proteins, and the reduction of BCL-2 levels. In addition, AKT and pAKT protein expressions were reduced in female M. pomifera-treated cells, revealing that female plant extract also inhibits PI3K/Akt signaling pathways. These results suggest that phytochemicals in M. pomifera extracts could be promising for developing breast cancer therapeutics.

Development of Peptide Displacement Assays to Screen for Antagonists of DDB1 Interactions.

The DNA damage binding protein 1 (DDB1) is an essential component of protein complexes involved in DNA damage repair and the ubiquitin-proteasome system (UPS) for protein degradation. As an adaptor protein specific to Cullin-RING E3 ligases, DDB1 binds different receptors that poise protein substrates for ubiquitination and subsequent degradation by the 26S proteasome. Examples of DDB1-binding protein receptors are Cereblon (CRBN) and the WD-repeat containing DDB1- and CUL4-associated factors (DCAFs). Cognate substrates of CRBN and DCAFs are involved in cancer-related cellular processes or are mimicked by viruses to reprogram E3 ligases for the ubiquitination of antiviral host factors. Thus, disrupting interactions of DDB1 with receptor proteins might be an effective strategy for anticancer and antiviral drug discovery. Here, we developed fluorescence polarization (FP)-based peptide displacement assays that utilize full-length DDB1 and fluorescein isothiocyanate (FITC)-labeled peptide probes derived from the specific binding motifs of DDB1 interactors. A general FP-based assay condition applicable to diverse peptide probes was determined and optimized. Mutagenesis and biophysical analyses were then employed to identify the most suitable peptide probe. The FITC-DCAF15 L49A peptide binds DDB1 with a dissociation constant of 68 nM and can be displaced competitively by unlabeled peptides at sub-μM to low nM concentrations. These peptide displacement assays can be used to screen small molecule libraries to identify novel modulators that could specifically antagonize DDB1 interactions toward development of antiviral and cancer therapeutics.

Competitive Microarray Screening Reveals Functional Ligands for the DHX15 RNA G-Quadruplex.

RNAs are increasingly considered valuable therapeutic targets, and the development of methods to identify and validate both RNA targets and ligands is more important than ever. Here, we utilized a bioinformatic approach to identify a hairpin-containing RNA G-quadruplex (rG4) in the 5' untranslated region (5' UTR) of DHX15 mRNA. By using a novel competitive small molecule microarray (SMM) approach, we identified a compound that specifically binds to the DHX15 rG4 (K D = 12.6 ± 1.0 μM). This rG4 directly impacts translation of a DHX15 reporter mRNA in vitro, and binding of our compound (F1) to the structure inhibits translation up to 57% (IC50 = 22.9 ± 3.8 μM). This methodology allowed us to identify and target the mRNA of a cancer-relevant helicase with no known inhibitors. Our target identification method and the novelty of our screening approach make our work informative for future development of novel small molecule cancer therapeutics for RNA targets.

Optogenetic Engineering of STING Signaling to Remotely Control anti-Tumor Immunity

The cGAS-STING signaling pathway is regarded as a promising target for cancer therapeutics development. Here we present an ultra-light-sensitive optogenetic device, designated LiSmore for light-inducible SMOC-like repeats, that remotely control STING activation and downstream gene expression in antigen-presenting cells to mount innate immunity. We demonstrate that noninvasive light-triggered STING modulation effectively promotes dendritic cell (DC) maturation and antigen presentation, allowing T cells to be effectively sensitized to engage tumor antigens, thereby photo-boosting anti-tumor immune response. Importantly, combining LiSmore with immune checkpoint blocker (ICB) synergistically enhances antitumor effcacy in an immunosuppressive lung cancer model, which otherwise remains largely unresponsive to ICB treatment. Our findings establish that targeted optogenetic activation of STING signaling allows for the remote control of DC functions by boosting anti-tumor immunity at the tumor sites. Hence, LiSmore sets the stage for the development of wireless optogenetic immunomodulatory therapies in a light-switchable manner. Acknowledgment: This work was supported by the Welch Foundation (BE-1913-20220331 to Y.Z.), the Cancer Prevention and Research Institutes of Texas (RP210070 to Y.Z.), and the National Institutes of Health (R01GM144986 to Y.Z., R01HL134780 to R01 Y.H., R01HL146852 to Y.H., and R01CA240258 to Y.H.). Images were created by Biorender.com. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Allosteric Modulation of the YAP/TAZ-TEAD Interaction by Palmitoylation and Small-Molecule Inhibitors.

The Hippo signaling pathway is a highly conserved signaling network that plays a central role in regulating cellular growth, proliferation, and organ size. This pathway consists of a kinase cascade that integrates various upstream signals to control the activation or inactivation of YAP/TAZ proteins. Phosphorylated YAP/TAZ is sequestered in the cytoplasm; however, when the Hippo pathway is deactivated, it translocates into the nucleus, where it associates with TEAD transcription factors. This partnership is instrumental in regulating the transcription of progrowth and antiapoptotic genes. Thus, in many cancers, aberrantly hyperactivated YAP/TAZ promotes oncogenesis by contributing to cancer cell proliferation, metastasis, and therapy resistance. Because YAP and TAZ exert their oncogenic effects by binding with TEAD, it is critical to understand this key interaction to develop cancer therapeutics. Previous research has indicated that TEAD undergoes autopalmitoylation at a conserved cysteine, and small molecules that inhibit TEAD palmitoylation disrupt effective YAP/TAZ binding. However, how exactly palmitoylation contributes to YAP/TAZ-TEAD interactions and how the TEAD palmitoylation inhibitors disrupt this interaction remains unknown. Utilizing molecular dynamics simulations, our investigation not only provides detailed atomistic insight into the YAP/TAZ-TEAD dynamics but also unveils that the inhibitor studied influences the binding of YAP and TAZ to TEAD in distinct manners. This discovery has significant implications for the design and deployment of future molecular interventions targeting this interaction.

A novel bispecific antibody drug conjugate targeting HER2 and HER3 with potent therapeutic efficacy against breast cancer.

Antibody drug conjugate (ADC) therapy has become one of the most promising approaches in cancer immunotherapy. Bispecific targeting could enhance the efficacy and safety of ADC by improving its specificity, affinity and internalization. In this study we constructed a HER2/HER3-targeting bispecific ADC (BsADC) and characterized its physiochemical properties, target specificity and internalization in vitro, and assessed its anti-tumor activities in breast cancer cell lines and in animal models. The HER2/HER3-targeting BsADC had a drug to antibody ratio (DAR) of 2.89, displayed a high selectivity against the target JIMT-1 breast cancer cells in vitro, as well as a slightly higher level of internalization than HER2- or HER3-monospecific ADCs. More importantly, the bispecific ADC potently inhibited the viability of MCF7, JIMT-1, BT474, BxPC-3 and SKOV-3 cancer cells in vitro. In JIMT-1 breast cancer xenograft mice, a single injection of bispecific ADC (3 mg/kg, i.v.) significantly inhibited the tumor growth with an efficacy comparable to that caused by combined injection of HER2 and HER3-monospecific ADCs (3 mg/kg for each). Our study demonstrates that the bispecific ADC concept can be applied to development of more potent new cancer therapeutics than the monospecific ADCs.

Targeting Telomere Dynamics as an Effective Approach for the Development of Cancer Therapeutics.

Telomere is a protective structure located at the end of chromosomes of eukaryotes, involved in maintaining the integrity and stability of the genome. Telomeres play an essential role in cancer progression; accordingly, targeting telomere dynamics emerges as an effective approach for the development of cancer therapeutics. Targeting telomere dynamics may work through multifaceted molecular mechanisms; those include the activation of anti-telomerase immune responses, shortening of telomere lengths, induction of telomere dysfunction and constitution of telomerase-responsive drug release systems. In this review, we summarize a wide variety of telomere dynamics-targeted agents in preclinical studies and clinical trials, and reveal their promising therapeutic potential in cancer therapy. As shown, telomere dynamics-active agents are effective as anti-cancer chemotherapeutics and immunotherapeutics. Notably, these agents may display efficacy against cancer stem cells, reducing cancer stem levels. Furthermore, these agents can be integrated with the capability of tumor-specific drug delivery by the constitution of related nanoparticles, antibody drug conjugates and HSA-based drugs.

Empowering Graph Neural Networks with Block-Based Dual Adaptive Deep Adjustment for Drug Resistance-Related NcRNA Discovery.

Drug resistance to chemotherapeutic agents remains a formidable challenge in cancer treatment, significantly impacting treatment efficacy. Extensive research has exposed the intimate involvement of noncoding RNAs (ncRNAs) in conferring resistance to cancer drugs. Understanding the intricate associations between ncRNAs and drug resistance is of pivotal importance in advancing clinical interventions and expediting drug development. However, traditional biological experimental methods are hampered by limitations, such as labor intensiveness, time consumption, and constraints in scalability. Addressing these challenges necessitates the development of efficient computational methods for the accurate prediction of potential ncRNA-drug resistance associations (NDRA). However, most existing predictive models primarily focus on known ncRNA-drug resistance associations, often neglecting the critical aspect of similarity information between ncRNAs and drug resistance. This oversight may hinder the accuracy of characterizing these associations. To overcome the limitations of existing computational models, we proposed B-NDRA, a computational framework designed for the discovery of drug resistance-related ncRNA. Initially, we constructed a heterogeneous graph that integrates ncRNA-drug resistance pairs, leveraging both known associations and similarity fusion information between ncRNAs and drug resistance. Subsequently, we employed an attention mechanism to aggregate local features of graph nodes following a dimensionality reduction of node features. Further, a graph neural network (GNN) facilitated the learning of global node embeddings. Notably, the integration of dual adaptive deep adjustment architectures, encompassing intrablock and interblock methodologies, enabled efficient extraction of global features while balancing local and global features. Finally, B-NDRA employed a multilayer perceptron to predict associations between ncRNAs and drug resistance. Through rigorous 5-fold cross-validation, B-NDRA achieved average AUC, AUPR, Accuracy, Precision, Recall, and F1-score values of 92.2%, 91.9%, 84.88%, 86.9%, 82.37%, and 84.44%, respectively. Furthermore, comparative evaluations were conducted on established models, namely, GAEMDA, GRPAMDA, and LRGCPND. The results, obtained through three distinct 5-fold cross-validation strategies, demonstrated a notable performance improvement across almost all metrics for our B-NDRA. Specific case studies targeting Doxorubicin and Imatinib further validated the practicality of our B-NDRA in discovering potential NDRA. These results confirm the potential of our B-NDRA as a valuable tool in advancing cancer research and therapeutic development. The source code and data set of B-NDRA can be found at https://github.com/XuanLi1145/B-NDRA.

Abstract 4979: Genomic profiling of early-onset metastatic colorectal cancer based on tumor sample location

Abstract Background: Here, we describe analyses towards identifying and comparing genetic variations between the primary and metastatic sites in early-onset metastatic colorectal cancer patients. Methods: We selected patients with early-onset metastatic colorectal cancer (under 50 years old) using data from the American Association for Cancer Research Project GENIE (version 14.1). We used the Fisher exact test to compare genetic mutations between the primary tumor and metastatic sites, complemented by the Benjamini-Hochberg adjustment method. Results: In a total of 1,791 patients with early-onset metastatic colorectal cancer, 27.1% had tumor samples from metastatic sites, while the majority, 72.9%, were from the primary tumor location. The most common mutations found were in the TP53 gene (77.6%), followed by APC (76.0%), KRAS (42.4%), and PIK3CA (19.0%). Notably, the metastatic samples had a significantly higher occurrence of SMAD4 mutations compared to their primary site counterparts (20.8% vs. 14.0%, p<0.001, q<0.001). Conversely, the primary tumor samples exhibited higher frequencies of TCF7L2 and ARID1A mutations (16.9% vs. 10.6%, p<0.001, q<0.001, and 13.0% vs. 6.4%, p<0.001, q<0.001, respectively). Conclusion: Determining the specific genes responsible for the formation of metastatic tumors is crucial for a deeper understanding of the disease's underlying biology in early-onset metastatic colorectal cancer. Such genomic details are crucial to pave the way to the discovery of potential biomarkers for diagnosis and the development of new cancer therapeutics. Citation Format: Muhammet Ozer, Suleyman Y. Goksu, Busra Bacik Goksu, Nina N. Sanford, Amy Jones, Nilesh Verma, Syed Kazmi. Genomic profiling of early-onset metastatic colorectal cancer based on tumor sample location [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 4979.

Abstract 4897: Personalized cell surface target identification from pan-cancer RNA-seq and proteomics profiling of tumors

Abstract In its third phase, the Clinical Proteomic Tumor Analysis Consortium (CPTAC) program collected pan-cancer data from 1,069 patients profiling the transcriptome, proteome, and phospho-proteome of tumors and adjacent tissues from ten cancer types. To identify potential immunotherapeutic candidates from this CPTAC cohort, we searched for cell-surface proteins that are highly expressed in tumor subtypes compared to their expression in normal tissues and cell types from ARCHS4 and the Genotype-Tissue Expression (GTEx) resources. For each cancer type, tumor samples were first clustered into subtypes based on RNA-seq data, and then cell surface targets were prioritized for each cluster. These targets were subsequently confirmed for high protein expression in the tumor subtypes. Tumor samples were also processed by their classification into immune subtypes to identify targets specific to hot (CD8+/IFNG+) and cold (CD8-/IFNG-) tumors of each cancer type. For each cancer type, the computational pipeline identified ~30 cell surface proteins that are highly expressed in the tumor and lowly expressed across tissues and cell types in both the ARCHS4 and GTEx backgrounds. Many of these targets are also robustly differentially expressed at the proteome level. Several targets were shared across tumor types, including VTCN1 and TMPRSS4. Altogether, this rational approach to identify potential targets demonstrates a pipeline that can be applied for personalized cancer diagnosis and therapeutic development. Citation Format: Giacomo B. Marino, Eden Z. Deng, Daniel J.B. Clarke, Weiping Ma, Pei Wang, Adam C. Resnick, Avi Ma'ayan. Personalized cell surface target identification from pan-cancer RNA-seq and proteomics profiling of tumors [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 4897.

Abstract 1981: Profiling of protein interactome with cysteine-reactive libraries led to the discovery of EML4ALK dimerizers

Abstract Cysteine covalent binders enable direct interactions with previously deemed undruggable protein targets, revolutionizing cancer therapeutics development. The primary focus has been on tailoring single-warhead compounds to target specific cysteine residues within the functional domains of target proteins. However, the biochemical properties including dimerization, induced conformational changes, and interactome disruption have been underexplored, presenting an ongoing limitation in current drug discovery approaches. In this study, we generated a library of 32 cysteine-reactive warhead compounds using various combinations of scaffolds and warheads to represent diverse reactivities. A combinatory assay approach, including cysteine druggability mapping (CDM) to discover reactive residues and SDS-PAGE fractionation assays to identify disrupted protein interaction events, was employed. Characterization of the library revealed distinct reactive cysteines and dimerization profiles among the 32 unique compounds. Compound 1C9, identified as a lead compound, demonstrated significant dimerization of EML4, a common fusion gene partner in lung cancer. Using the EML4ALK fusion gene as a proof of concept, we explored potential mechanisms underlying the compound-induced dimerization of EML4. Subsequent structure-activity relationship (SAR) studies and screening of 70 additional compounds were conducted to optimize ALK dimerization and minimize off-target effects. The enhanced compound disrupted the ALK cellular signaling pathways AKT and ERK upon dimerization of the EML4ALK fusion gene. Additionally, we discovered that covalent dimerization induced EML4ALK degradation without requiring a ubiquitin ligase like a PROTAC. In conclusion, our work has uncovered a novel class of cysteine covalent binders, which we believe are valuable tools to modulate protein-protein interactions in previously undruggable proteins in cancer. This discovery holds significant therapeutic potential for future drug development. Citation Format: Diane Yang, Stefan Harry, Elizabeth Codd, Stefan T. Kaluziak, Alexander D. Carlin, Edwin Zhang, Zavontae Oppong-Holmes, Wenxin Yang, Abigail Smith, Dawn Mitchell, Mariko Hara, Siwen Zhang, Maristela Onozato, Liron Bar-Peled, Anthony J. Iafrate. Profiling of protein interactome with cysteine-reactive libraries led to the discovery of EML4ALK dimerizers [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 1981.

Liver X Receptors (LXRs) in cancer-an Eagle's view on molecular insights and therapeutic opportunities.

Cancer has become a serious health burden that results in high incidence and mortality rates every year, mainly due to various molecular alterations inside the cell. Liver X receptors (LXRs) dysregulation is one among them that plays a vital role in cholesterol metabolism, lipid metabolism and inflammation and also plays a crucial role in various diseases such as obesity, metabolic dysfunction-associated fatty liver disease (MAFLD), cardiovascular diseases, Type 2 diabetes, osteoporosis, and cancer. Studies report that the activation of LXRs inhibits cancer growth by inhibiting cellular proliferation, inducing apoptosis and autophagy, regulating cholesterol metabolism, various signalling pathways such as Wnt, and PI3K/AKT, modulating the expression levels of cell-cycle regulators, and promoting antitumor immunity inside the tumor microenvironment. In this review, we have discussed the role, structure, and functions of LXRs and also summarized their ligands along with their mechanism of action. In addition, the role of LXRs in various cancers, tumor immunity and tumor microenvironment (TME) along with the importance of precision medicine in LXR-targeted therapies has been discussed to emphasize the LXRs as potent targets for the development of novel cancer therapeutics.

DDX3X and Stress Granules: Emerging Players in Cancer and Drug Resistance.

The DEAD (Asp-Glu-Ala-Asp)-box helicase 3 X-linked (DDX3X) protein participates in many aspects of mRNA metabolism and stress granule (SG) formation. DDX3X has also been associated with signal transduction and cell cycle regulation that are important in maintaining cellular homeostasis. Malfunctions of DDX3X have been implicated in multiple cancers, including brain cancer, leukemia, prostate cancer, and head and neck cancer. Recently, literature has reported SG-associated cancer drug resistance, which correlates with a negative disease prognosis. Based on the connections between DDX3X, SG formation, and cancer pathology, targeting DDX3X may be a promising direction for cancer therapeutics development. In this review, we describe the biological functions of DDX3X in terms of mRNA metabolism, signal transduction, and cell cycle regulation. Furthermore, we summarize the contributions of DDX3X in SG formation and cellular stress adaptation. Finally, we discuss the relationships of DDX3X, SG, and cancer drug resistance, and discuss the current research progress of several DDX3X inhibitors for cancer treatment.