Specific Oncogenes Research Articles

The intervention of B. longum metabolites in Fnevs' carcinogenic capacity: A potential double-edged sword.

Colorectal cancer (CRC) ranks among the most prevalent malignant tumors globally. Fusobacterium nucleatum and its metabolites are effective biological targets for colon cancer promotion. Probiotics such as Bifidobacterium can block the occurrence and development of CRC by regulating the host intestinal mucosal immunity, eliminating carcinogens, and interfering with tumor cell proliferation and apoptosis. We selected six Bifidobacterium species to explore the inhibitory effect of their cell-free supernatant (CFS) on Fusobacterium nucleatum, and screened the best functional strain Bifidobacterium longum (B. longum) to explore its intervention effect on Fnevs infection of CRC cells. In the genus Bifidobacterium, B. longum-CFS can effectively inhibit the growth and membrane formation of Fusobacterium nucleatum. The metabolites of B. longum can inhibit the proliferation, migration and invasion of Fnevs-infected CRC cells. However, the transcriptomic analysis of Fnevs-infected CRC cells treated with Bl-CFS revealed that Bl-CFS exerted inhibitory effects on the expression of specific oncogenes (e.g., Myc, IL16, KCNN2, ACSBG1, Pum1, MET, NR5A2), while simultaneously promoting the expression of other oncogenes. This modulation potentially enhances the proliferation, epithelial-mesenchymal transition (EMT), stemness properties and other characteristics associated with CRC cells. Metabolomics also showed that Bl-CFS altered organic acid and lipid metabolism in Fnevs-infected CRC cells, and switched energy supply from aerobic glucose metabolism (TCA cycle) to anaerobic glycolysis, which increased the malignancy potential of CRC cells. The observed outcome may be attributed to the presence of both probiotics and toxic substances in the metabolites derived from Bifidobacterium longum. Therefore, this study concludes that the anti-colorectal cancer (CRC) effect of natural metabolites derived from Bifidobacterium longum is limited. Future investigations should focus on refining these natural substances and optimizing their composition ratios to extract their essence while eliminating impurities, thereby obtaining anticancer biologics with exceptional and consistent efficacy.

Epigenetic Modification of Muscarinic Acetylcholine Receptors in Squamous Cell Carcinoma of the Head and Neck.

The five members of the mammalian muscarinic acetylcholine receptor family are encoded by the cholinergic receptor, muscarinic, 1-5 (CHRM1-5) genes. CHRM genes are incriminated in formation of various cancer types, but their roles in head and neck squamous cell carcinoma (HNSCC) are improperly understood. Aberrant epigenetic modifications of specific tumor-suppressor genes and oncogenes are known to promote cancer development. We aimed to analyze the connection between methylation of CHRM genes and HNSCC recurrence, with specific reference to human papillomavirus (HPV)-positive oropharyngeal carcinoma. We investigated the methylation state of CHRM1-CHRM5 genes expressed in 305 samples of primary HNSCCs by quantitative methylation-specific polymerase chain reaction. We explored associations between methylation of these genes and the clinicopathological characteristics of HNSCC (location of the tumor as well as recurrence) Results: We found 1.08±0.94 methylated genes per sample (range=0-5), with promoters of CHRM1-5 genes methylated in 85.9%, 47.5%, 10.2%, 17.7%, and 19.3%, respectively, of the evaluated samples. Methylation levels of CHRM2 were significantly raised in HNSCC samples compared to corresponding normal tissues (p<0.001). Although there was no significance of tumor location, analysis by Kaplan-Meier estimate and multivariate Cox proportional hazard methods showed that methylated CHRM2 was significantly associated with increased recurrence of HNSCC with HPV-positive oropharyngeal cancer. CHRM methylation status is associated with HNSCC pathogenesis.

The role of GOT1 in cancer metabolism.

GOT1, a cytoplasmic glutamic oxaloacetic transaminase, plays a critical role in various metabolic pathways essential for cellular homeostasis and dysregulated metabolism. Recent studies have highlighted the significant plasticity and roles of GOT1 in metabolic reprogramming through participating in both classical and non-classical glutamine metabolism, glycolytic metabolism, and other metabolic pathways. This review summarizes emerging insights on the metabolic roles of GOT1 in cancer cells and emphasizes the response of cancer cells to altered metabolism when the expression of GOT1 is altered. We review how cancer cells repurpose cell intrinsic metabolism and their flexibility when GOT1 is inhibited and delineate the molecular mechanisms of GOT1's interaction with specific oncogenes and regulators at multiple levels, including transcriptional and epigenetic regulation, which govern cellular growth and metabolism. These insights may provide new directions for cancer metabolism research and novel targets for cancer treatment.

TLE1 corepressor promotes gefitinib resistance in lung cancer A549 cells via E‑cadherin silencing.

As a putative lung specific oncogene, the transducin-like enhancer of split 1 (TLE1) corepressor drives an anti-apoptotic and pro-epithelial-mesenchymal transition (EMT) gene transcriptional programs in human lung adenocarcinoma (LUAD) cells, thereby promoting anoikis resistance and tumor aggressiveness. Through its survival- and EMT-promoting gene regulatory programs, TLE1 may impact drug sensitivity and resistance in lung cancer cells. In the present study, a novel function of TLE1 was uncovered as an inhibitor of the antitumor effects of the epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) gefitinib in the human LUAD cell line A549, which exhibits moderate sensitivity to EGFR-TKI. While upregulation of TLE1 expression potently inhibited the proliferation inhibitory and apoptotic effects of gefitinib in A549 cells, downregulation of endogenous TLE1 in these cells enhanced their sensitivity to gefitinib. In experimentally derived gefitinib-resistant A549 cells (A549GR) that have acquired EMT, TLE1 expression is upregulated as compared with parental A549 cells, and acute ablation of TLE1 expression is sufficient to partially restore gefitinib sensitivity and attenuate EMT phenotype. Mechanistic studies showed that TLE1 confers gefitinib resistance in A549 cells in part via downregulation of E-cadherin, a known potentiator of EGFR-TKI sensitivity and apoptosis induction. Importantly, the TLE1/E-cadherin transcriptional axis is negatively regulated by gefitinib to trigger apoptosis via the Bcl-2-inhibitor of transcription 1 cell death pathway. In conclusion, these results indicate a novel role of TLE1 in modulating EGFR-TKI sensitivity in lung cancer cells via regulation of E-cadherin expression, and its upregulation may potentiate EGFR-TKI resistance in LUAD.

How to Keep Up With Molecular Testing and Targeted Therapies in Lung Cancer.

Until the early 2000s, advanced or metastatic non-small cell lung cancer (NSCLC) was treated as a single disease with all histologic subtypes treated alike with standard chemotherapy agents. Over the past two decades, the treatment paradigms for advanced NSCLC have changed dramatically with the discovery of multiple targeted therapies that are now approved for the treatment of NSCLC tumors with specific oncogene drivers or molecular alterations. Molecular testing has become integrated and critical for the clinical management of advanced NSCLC. The discovery and success of these targeted therapies have reshaped the classification of NSCLC on the basis of molecular classification and enabled a personalized approach in thoracic oncology. In this review, we discuss recent developments in the molecular profiling of NSCLC, and approved and emerging targeted therapies for the treatment of NSCLC.

A comprehensive review of cancer: CRISPR and its application in lung cancer with a potential in overcoming EGFR mutations

As a comprehensive review of cancer, oncogenes, and CRISPR, this review explores the transformative potential of CRISPR technology in combating cancer, particularly focusing on lung cancer and oncogenes. CRISPR’s precision gene-editing capabilities offer a promising avenue for developing more targeted cancer therapies, overcoming the limitations of current treatments such as chemotherapy and radiation, which often fail due to cancer cell heterogeneity and resistance. Additionally, this review proposes the potential use of CRISPR to target specific oncogenes like EGFR and its significant promise for improving treatment outcomes in lung cancer by directly modifying or regulating gene function. This review synthesizes current research, highlighting the integration of CRISPR with other therapeutic modalities to enhance the effectiveness of cancer treatments, delivery systems that improve targeting and minimize off-target effects, and the future directions in CRISPR-mediated lung cancer therapy.

Rapid degradation of DHX36 revealing its transcriptional role by interacting with G‐quadruplex

AbstractAccumulating evidence indicates that G‐quadruplexes (G4s) are involved in transcriptional regulation. Previous studies have demonstrated that DHX36 preferentially resolves G4s, suggesting its potential impact on gene transcription mediated by these structures. However, systematic validation is required to establish a link between DHX36 activity and its roles in transcriptional regulation. In this study, we investigate the role of DHX36 in transcription. First, we employ the cleavage under targets and tagmentation (CUT&amp;Tag), an efficient method for mapping protein–DNA interactions, to identify the binding sites in the chromatin of MCF‐7 cells. Subsequently, we use the auxin‐inducible degron (AID) protein degradation system and improved nascent RNA sequencing method acrylonitrile‐mediated uridine‐to‐cytidine conversion sequencing (AMUC‐seq) to pinpoint genes directly regulated by DHX36. Our results reveal a significant enrichment of G4 structures at DHX36 target sites, predominantly located in active genomic regions. In vitro assays further demonstrate DHX36's interaction with G4 sequences from three specific oncogenes. These findings underscore the potential role of DHX36 in modulating gene transcription through G4 structures.

Top advances of the year: Targeted therapy for lung cancer.

The past year has offered significant advancements in the field of non-small cell lung cancer (NSCLC), both in the early and advanced disease settings. The identification of guideline-recommended actionable targets has provided the foundation for developing multiple new therapeutic agents. There has been a focus on developing drugs designed to overcome acquired resistance, a limitation of tyrosine kinase inhibitor-based therapy in lung cancer. In addition, there is an emerging trend toward combination therapies for patients in the first-line setting with the goal of preventing or delaying resistance. Another promising area of development has been the use of antibody-drug conjugates, where there are the initial reports of central nervous system efficacy and activity in patients with genomic alterations. Over the past year, numerous publications and presentations have highlighted multiple therapeutic advances, offering new treatment options for patients with NSCLC. The focus of this review is to summarize the most impactful findings, emphasizing their significance in the evolving treatment landscape for NSCLC. Several landmark trials in lung cancer with practice-changing clinical implications have been presented and published in 2023. This article reviews a selection of these trials as they relate to early and advanced-stage oncogene-driven lung cancer. The ADAURA and ALINA trials, in which targeted therapy given in the adjuvant setting has demonstrated improved clinical outcomes, are reviewed. In the advanced-stage setting, recent trials in the context of specific oncogene drivers are reviewed, including EGFR, ALK, ROS1, RET, ERBB2 (HER2), BRAF, MET exon 14 skipping (METex14), and KRAS alterations. Also discussed are the results of several trials that have evaluated the use of combination therapies and resistance-mechanism agnostic treatment strategies. PLAIN LANGUAGE SUMMARY: Targeted therapy plays an important role for patients with early and advanced-stage non-small cell lung cancer carrying specific genetic alterations. New strategies that combine multiple therapies are now being studied in randomized clinical trials, with the goal of enhancing the effectiveness of targeted therapy for patients with advanced lung cancer.

Gene-Based Therapy for Brain Cancer: Promises and Challenges

Brain cancer, including gliomas and other malignant tumors, represents a devastating and challenging disease with limited treatment options and poor prognosis. Conventional therapies such as surgery, radiation, and chemotherapy have shown limited success, necessitating the exploration of alternative approaches. Gene-based therapy has emerged as a promising frontier in precision medicine, leveraging our growing understanding of the genetic and molecular drivers underlying brain tumor development and progression. This paper provides an overview of recent advancements in gene-based therapies for brain cancer, including gene editing techniques, gene silencing strategies, Immunotherapy, and more. Notably, these approaches aim to target specific oncogenes, tumor suppressor genes, and immune-related genes to inhibit tumor growth, induce apoptosis, and enhance the patient's immune response against cancer cells. Moreover, gene-based therapies offer the potential for personalized treatments tailored to individual patients based on their unique genetic profile, increasing treatment efficacy and minimizing adverse effects. While gene-based therapies have shown promising preclinical and early clinical results, challenges related to delivery, safety, and off-target effects remain to be addressed. This abstract emphasizes the urgent need for further research and large-scale clinical trials to establish the safety and long-term efficacy of gene-based therapies for brain cancer treatment. As the field continues to evolve, gene-based therapy holds great promise in reshaping the landscape of brain cancer management and providing hope for improved patient outcomes in the future.

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.

Extracellular Vesicular Analysis of Glypican 1 mRNAand Protein for Pancreatic Cancer Diagnosis and Prognosis.

Detecting pancreatic duct adenocarcinoma (PDAC) in its early stages and predicting late-stage patient prognosis undergoing chemotherapy is challenging. This work shows that the activation of specific oncogenes leads to elevated expression of mRNAs and their corresponding proteins in extracellular vesicles (EVs) circulating in blood. Utilizing an immune lipoplex nanoparticle (ILN) biochip assay, these findings demonstrate that glypican 1 (GPC1) mRNA expression in the exosomes-rich (Exo) EV subpopulation and GPC1 membrane protein (mProtein) expression in the microvesicles-rich (MV) EV subpopulation, particularly the tumor associated microvesicles (tMV), served as a viable biomarker for PDAC. A combined analysis effectively discriminated early-stage PDAC patients from benign pancreatic diseases and healthy donors in sizable clinical from multiple hospitals. Furthermore, among late-stage PDAC patients undergoing chemotherapy, lower GPC1 tMV-mProtein and Exo-mRNA expression before treatment correlated significantly with prolonged overall survival. These findings underscore the potential of vesicular GPC1 expression for early PDAC screenings and chemotherapy prognosis.

Visualization of microRNA therapy in cancers delivered by small extracellular vesicles

MicroRNA (miRNA) delivery by extracellular vesicles (EVs) has recently inspired tremendous developments in cancer treatments. However, hybridization between miRNA and its target mRNA is still difficult to be imaged in vivo to assess the therapeutic effects in time. Herein we design a nano-scale fluorescent “off–on” complex encapsulated by small extracellular vesicles (sEVs) for real-time visualization and evaluation of gene therapy efficiency in human gastric cancer cells and murine xenograft tumor models. The complex is formed by π–π stacking between graphene quantum dots (GQDs) and tumor suppressor miR-193a-3p conjugated fluorescent tag whose signals remain off when binding to GQDs. Loaded into sEVs using tunable sonication techniques, the GQDs/Cy5-miR particles enter the tumor cells and promote miR-193a-3p escape from endosomes. The miR-193a-3p in GQDs/Cy5-miR is unleashed to pair the specific target oncogene cyclin D1 (CCND1), therefore turning on the fluorescence of miRNA tags. We find out that GQDs/Cy5-miR@sEVs can activate the “turn-on” fluorescent signal and exhibit the longest retention time in vivo, which suggests a minimized degradation of miR-193a-3p in dynamic processes of miRNA-mRNA binding. More importantly, GQDs/Cy5-miR@sEVs significantly promote cancer apoptosis in vitro and in vivo via the enhanced cellular uptake. Our study demonstrates that GQDs/Cy5-miR@sEVs represent an efficient and refined theranostic platform for gene therapy in cancers.Graphical

First Report of Asymptomatic Solitary High-Grade B-Cell Lymphoma NOS: An Enigmatic Entity

Background High-grade B cell lymphoma (HGBL) is a new disease entity introduced by WHO in 2016, including two types: HGBL with a double hit (DH) or triple hit (TH) and HGBL, not otherwise specified (NOS). HGBL DH/TH are defined by genetic rearrangements of specific oncogenes MYC, BCL2 and/or BCL6, while HGBL NOS is defined purely base on morphology in the absence of these genes. HGBL DH/TH is known for its poor prognostication given its propensity to rapidly progress and disseminate, however HGBL NOS remains ill-defined and poorly understood with no tangible literature describing its clinical nature and therapeutic susceptibility. Case presentation A 76-year-old post-menopausal woman with no significant PMH presented for evaluation of painless hematuria during a routine office visit. Evaluation with imaging showed a suspicious incidental liver mass concerning for possible metastatic or primary liver cancer. Obtained labs were unremarkable, including serum LDH, serological testing for hepatitis B/C and HIV1/2, and typical tumor markers. PET scan showed focal uptake of tracer in liver with no nodal involvement. Liver biopsy revealed diffuse infiltration by atypical lymphocytes. Immunohistochemical analysis showed CD20 and CD10 positivity, negative CD30, and high Ki-67 proliferation rate of 100%, however the absence of MYC, BCL6, BCL2, and t(8;14) rearrangements on FISH ruled out Burkitt and DH/TH lymphoma, consistent with HGBL-NOS. Following discussions with Henry Ford Lymphoma Tumor Board, patient was treated with six cycles of R-CHOP, where follow-up imaging indicated remission of her lymphoma. Conclusion This represents an extraordinary first report of HGBL NOS manifesting as an isolated primary hepatic lymphoma in the complete absence of clinical symptoms. The significance of this case lies in its atypical extra-nodal site of involvement and total absence of clinical symptoms and serological markers, underscoring the unfulfilled need to further describe this enigmatic entity.

In Vivo Modeling of T-Cell Acute Lymphoblastic Leukemia Reveals Synergistic Oncogenic Pathways and Bcl11b Haploinsufficiency As a Potential Therapeutic Vulnerability

For decades, T-ALL models were based on retroviral overexpression of NOTCH1 in murine hematopoietic stem cells (HSCs). This induces aggressive T-ALL but does not reflect the genetic and clinical heterogeneity of the disease. Large-scale genomic analyses have mapped the detailed landscape of T-ALL driver events over recent years, but how these diverse oncogenic events interact in T-ALL pathogenesis and which vulnerabilities this creates remains incompletely explored. This is in part due to the lack of appropriate mouse models that recapitulate the complex disease biology and are suitable to identify and study potential therapeutic targets and interventions in a more realistic context. We modeled the genetic heterogeneity of T-ALL through in vivo multiplexing of gain-of-function and loss-of-function oncogenic events known to drive the disease. We developed a novel mouse strain that expresses Cre-recombinase and an inducible Cas9 only in the thymus ( LSL.Cas9 x Lck-cre) along with a lentiviral vector system into which T-ALL specific oncogenes are cloned in antisense flanked by LOX66/71 sites. Gain-of-function events, such as the overexpression of transcriptional regulators ( Tlx1, Tal1, or Lmo2) and signal transducers ( NRAS G12D, PIK3CD E1021K) were induced in developing thymocytes by Cre-mediated inversion together CRISPR-Cas9 editing of recurrent T-ALL loss-of-function drivers. This combinatorial approach allowed to probe more than 2000 possible oncogenic mutational combinations in vivo. Transplantation of HSCs from LSL.Cas9 x Lck-cre mice transduced with our vector system into sublethally irradiated mice led to T-ALL development with different morphology and disease phenotypes. Developing leukemia harbored reproducible phenotypes, covering very immature CD4-CD8-CD25+CD44+ T-ALL in the Tlx1_NRAS subgroup, in contrast to the classical cortical CD4+CD8+CD3- phenotype (Tlx1_PIK3CD subgroup), as well as mature single-positive CD4+CD3+ or CD8+CD3+ blasts (Tal1_Lmo2 subgroup). We identified Tlx1, Tal1, Lmo2, NRAS G12Dand PIK3CD E1021Kas the main driver of disease phenotype and gene expression profile, whereas the loss-of-function mutations contributed to and accelerated the onset of the disease. Tumor-derived cell lines could be easily established and kept their phenotypic characteristics and mutation patterns. The resulting T-ALL tumors contained up to eight different disease-relevant genetic alterations, thus recapitulating the genetic complexity in humans and overcoming the long latency for spontaneous mutations in less complex mouse models. Among these, co-evolution of insertions and deletions in Notch1, Cdkn2a, Bcl11b, and Pten were among the most frequently observed mutations in definitive T-ALL, whereas others, e.g., in Dnm2, Phf6, Etv6, and Lef1, occurred more randomly. While gene editing by CRISPR-Cas9 mostly resulted in frame-shift mutations in both alleles, Bcl11b exhibited a strong haploinsufficient phenotype with exactly one knock-out and one intact allele in each case examined. Following this observation, further suppression of Bcl11b by shRNAs in Bcl11b +/- cell lines derived from our tumor models demonstrated rapid induction of cell death, which was more intense in T-ALL cells compared to non-malignant thymocytes. In addition, re-analysis of CRISPR-based loss-of-function screens of human hematopoietic cell lines retrieved from the Cancer Dependency Map confirmed BCLL11B as a strong selective dependency in human T-ALL. In summary, we model subgroup-specific T-ALL transformation through conditional and multiplexed in vivo gene editing and oncogene overexpression, thus creating a resource of novel mouse models that recapitulate the genetic and biological heterogeneity of the disease. Using our resource, we identified Bcl11b as a strong and selective context-specific dependency in T-ALL. Although Bcl11b is a transcription factor, our results could serve as an starting point for novel therapies that interfere with Bcl11b function, such as molecular glue degraders or protein interaction inhibitors.

The role of NFATc1 in the progression and metastasis of prostate cancer: A review on the molecular mechanisms and signaling pathways.

A common type of cancer among men is the prostate cancer that kills many people every year. The multistage of this disease and the involvement of the vital organs of the body have reduced the life span and quality of life of the people involved and turned the treatment process into a complex one. NFATc1 biomarker contributes significantly in the diagnosis and treatment of this disease by increasing its expression in prostate cancer and helping the proliferation, differentiation, and invasion of cancer cells through different signaling pathways. NFATc1 is also able to target the metabolism of cancer cells by inserting specific oncogene molecules such as c-myc that it causes cell growth and proliferation. Bone is a common tissue where prostate cancer cells metastasize. In this regard, the activity of NFATc1, through the regulation of different signaling cascades, including the RANKL/RANK signaling pathway, in turn, increases the activity of osteoclasts, and as a result, bone tissue is gradually ruined. Using Silibinin as a medicinal plant extract can inhibit the activity of osteoclasts related to prostate cancer by targeting NFATc. Undoubtedly, NFATc1 is one of the effective oncogenes related to prostate cancer, which has the potential to put this cancer on the path of progression and metastasis. In this review, we will highlight the role of NFATc1 in the progression and metastasis of prostate cancer. Furthermore, we will summarize signaling pathways and molecular mechanism, through which NFATc1 regulates the process of prostate cancer.

TRLS-14. TARGETING REPLICATIVE STRESS IN BRAIN TUMORS BY COMBINING ATR AND PARP INHIBITION

Abstract Pediatric brain tumors like MYC-amplified Medulloblastomas (MB) and Atypical Teratoid and Rhabdoid Tumors (AT/RT) continue to have poor survival rates despite recent advances in understanding tumor biology. MYC is an oncogenic transcription factor often expressed in MB and AT/RT at high levels. While direct inhibition of MYC by small molecules is an active area of research, such approaches lack clinical validation and are not yet actionable. Strategies to target MYC-driven brain tumors that are immediately translatable are urgently needed. Replication stress has been identified as a prominent source of tumorigenesis over the past decade and is a potential target for cancer therapy. Specific oncogenes induce elevated levels of replicative stress through aberrant activation of transcription and dysregulation of DNA replication. In these instances, replicative stress could be rescued by either metabolic supplementation or MYC expression. The activation of ATR and PARP are critical events in response to replicative stress. PARP inhibitors stall replication forks and promote the generation of single-strand DNA, which activates ATR. Genetic and pharmacological evidence suggests the sensitization of MYC-induced tumors to PARP inhibitors. Preclinical studies in diverse tumor backgrounds have demonstrated that the combination of ATR and PARP inhibition is synergistic and leads to premature entry into mitosis, enhanced replicative stress and cell death, and tumor regression. Additionally, a reduction in ATR activity can be lethal in oncogene-induced replication stress. Using high throughput drug screening across MB and AT/RT cell lines, we found that the CNS penetrant PARP inhibitor AZD9754 significantly potentiated the cytotoxicity of ATR inhibition. This emerging synergistic combination therapy reveals new therapeutic targets in MYC-driven replicative stress. Studies are ongoing to validate in vitro findings in vivo.

Impact of genomic alterations measured in circulating tumor DNA (ctDNA) on clinical response to telisotuzumab vedotin treatment in patients with non-small cell lung cancer (NSCLC).

9032 Background: The antibody-drug conjugate telisotuzumab vedotin (Teliso-V) is composed of the c-Met–targeting antibody telisotuzumab (ABT-700) linked to the microtubule inhibitor monomethyl auristatin E. In the LUMINOSITY study (NCT03539536), efficacy of Teliso-V was seen in patients (pts) with EGFR wildtype nonsquamous NSCLC and c-Met overexpression (≥25% tumor cells at 3+ intensity by IHC); overall response rate: 36.5%. Data are limited on whether specific driver oncogene states affect responses. We investigated genomic alterations in relation to response to Teliso-V in this population. Methods: Pts received 1.9 mg/kg Teliso-V monotherapy once every 2 weeks in LUMINOSITY. ctDNA was isolated from plasma collected at different timepoints. The PGDx elio plasma complete assay was used to identify genomic alterations in ctDNA samples. This assay included 521 genes for single nucleotide variants and insertion-deletion mutations, 38 for amplifications (amp), and 21 for translocations. Results: In total, 52 pts were included in the study; ctDNA from 48 pts was analyzed. The overall response rate among pts with ctDNA results was 37.5% (18 pts with partial response) compared with 36.5% for the ITT population of 52 pts. Genomic alterations are listed in the Table.Three out of 4 pts with MET amp at baseline responded, accounting for 17% of total responses. The observed MET amp frequency in this MET IHC preselected cohort was 8%, which is similar to the prevalence observed in tissue analysis by FISH. Of note, 1 nonresponder harbored a MET ex14del mutation at baseline, and a responder had a low-frequency mutation detected at the final visit. Mutations in KRAS were the most common genomic alteration and were detected in 13 (27%) pts at baseline. Three pts with a KRAS mutation were responders; among these, 2 out of 3 had a KRAS G12C mutation (seen in 3 pts total). Response rates were higher in pts with MET amp (75%; 95% CI: 0.30, 0.95) vs those without MET amp (34%; 0.22, 0.49), and higher in pts without KRAS mutations (43%; 0.28, 0.59) vs those with KRAS mutations (23%; 0.08, 0.50); however, confidence intervals were wide and larger sample sizes are needed. Conclusions: MET amp occurred more frequently in responders; however, Teliso-V activity was not restricted to these pts, as most responders were not MET amplified. Specific genomic alterations beyond MET may influence clinical response. The current analysis demonstrated numeric differences between pts with identified drivers who did or did not respond to Teliso-V. Additional research on this topic is needed in larger pt cohorts and/or with tissue-based NGS analyses. [Table: see text]

Oncogenic drivers dictate immune control of acute myeloid leukemia

Acute myeloid leukemia (AML) is a genetically heterogeneous, aggressive hematological malignancy induced by distinct oncogenic driver mutations. The effect of specific AML oncogenes on immune activation or suppression is unclear. Here, we examine immune responses in genetically distinct models of AML and demonstrate that specific AML oncogenes dictate immunogenicity, the quality of immune response and immune escape through immunoediting. Specifically, expression of NrasG12D alone is sufficient to drive a potent anti-leukemia response through increased MHC Class II expression that can be overcome with increased expression of Myc. These data have important implications for the design and implementation of personalized immunotherapies for patients with AML.

Therapeutic Effects of WT1 Silencing via Respiratory Administration of Neutral DOPC Liposomal-siRNA in a Lung Metastasis Melanoma Murine Model

The lungs represent a frequent target for metastatic melanoma as they offer a high-oxygen environment for tumor development. The overexpression of the WT1 protein has been associated with the occurrence of melanoma. In this study, we evaluated the effects of silencing the WT1 protein by siRNA in both in vitro in the B16F10 melanoma cell line and in vivo in a murine model of lung metastatic melanoma. We did this by implementing a novel respiratory delivery strategy of a neutral DOPC liposomal-siRNA system (L-siRNA). In vitro studies showed an effective silencing of the WT1 protein in the siRNAs' WT1-treated cells when compared with controls, resulting in a loss of the cell's viability and proliferation by inducing G1 arrest, the inhibition of the migration and invasion capacities of the cells, as well as the induction of apoptosis. In vivo, the respiratory administration of L-WT1 siRNA showed an efficient biodistribution on the lungs. After two weeks of treatment, the silencing of the WT1 protein resulted in an important antitumor activity that reduced the tumor weight. In the survival study, L-WT1 treatment could significantly delay the death of the animals. This work demonstrates the efficacy of the L-siRNA respiratory administration as a novel therapy to reduce pulmonary tumors and to increase survivability by silencing specific cancer oncogenes as WT1.

Exploration of the Relevance of MicroRNA Signatures for Cancer Detection and Multiclass Cancer Classification

miRNA expression profiles are heterogeneously expressed among cancer types, with miRNAs serving as highly tissue specific tumor suppressors and oncogenes. Machine learning methodologies have been used to develop high performance pan-cancer classification models and identify potentially novel miRNA biomarkers for clinical investigation. However, it is important to understand how such data science techniques correlate to established biological processes to advance integration into clinical environments. This research aims to assess how the top miRNA features selected by machine learning models relate to clinically and biologically verified miRNA biomarkers. We developed Support Vector Machine and Random Forest machine learning models for cancer classification, iteratively adding cancer classes to the multiclass models. The relationship between the selected top features (miRNAs) and clinically verified miRNA biomarkers was assessed through percent relevance, i.e., the number of verified miRNAs vs the number of selected features. We found that as the number of cancer classes increased, the performance metrics decreased, yet the percentage relevance of the miRNA feature selection signature slightly increased before stabilizing. Additionally, after conducting principal component analysis, the non-cancer tissues from all samples had very similar expression visualizations, while all cancerous tissues had unique profiles. The results indicated that models with a greater number of cancer classes shift towards focusing on cancer-diverse miRNAs of greater relevance with characterized functionality. This work suggests that miRNAs may be highly unique to specific cancerous tissues and can be strong biomarkers for detection and classification, but current verified biomarkers fall toward more cancer-wide miRNAs when detecting cancer.