Amy E Anderson, Kaustubh Parashar, Ke Jin, Julie Clor, Carlo E Stagnaro, Urvi Vani, Jaskirat Singh, Ada Chen, Yihong Guan, Priyanka Talukdar, Pavithra Sathishkumar, Damie J Juat, Hema Singh, Ritu Kushwaha, Xiaoning Zhao, Angelo Kaplan, Lisa Seitz, Matthew J Walters, Ester Fernandez-Salas, Nigel P C Walker, Christine E Bowman
{"title":"Characterization of AB598, a CD39 Enzymatic Inhibitory Antibody for the Treatment of Solid Tumors.","authors":"Amy E Anderson, Kaustubh Parashar, Ke Jin, Julie Clor, Carlo E Stagnaro, Urvi Vani, Jaskirat Singh, Ada Chen, Yihong Guan, Priyanka Talukdar, Pavithra Sathishkumar, Damie J Juat, Hema Singh, Ritu Kushwaha, Xiaoning Zhao, Angelo Kaplan, Lisa Seitz, Matthew J Walters, Ester Fernandez-Salas, Nigel P C Walker, Christine E Bowman","doi":"10.1158/1535-7163.MCT-23-0865","DOIUrl":"10.1158/1535-7163.MCT-23-0865","url":null,"abstract":"<p><p>AB598 is a CD39 inhibitory antibody being pursued for the treatment of solid tumors in combination with chemotherapy and immunotherapy. CD39 metabolizes extracellular adenosine triphosphate (eATP), an alarmin capable of promoting antitumor immune responses, into adenosine, an immuno-inhibitory metabolite. By inhibiting CD39, the consumption of eATP is reduced, resulting in a proinflammatory milieu in which eATP can activate myeloid cells to promote antitumor immunity. The preclinical characterization of AB598 provides a mechanistic rationale for combining AB598 with chemotherapy in the clinic. Chemotherapy can induce ATP release from tumor cells and, when preserved by AB598, both chemotherapy-induced eATP and exogenously added ATP promote the function of monocyte-derived dendritic cells via P2Y11 signaling. Inhibition of CD39 in the presence of ATP can promote inflammasome activation in in vitro-derived macrophages, an effect mediated by P2X7. In a MOLP8 murine xenograft model, AB598 results in full inhibition of intratumoral CD39 enzymatic activity, an increase in intratumoral ATP, a decrease of extracellular CD39 on tumor cells, and ultimately, control of tumor growth. In cynomolgus monkeys, systemic dosing of AB598 results in effective enzymatic inhibition in tissues, full peripheral and tissue target engagement, and a reduction in cell surface CD39 both in tissues and in the periphery. Taken together, these data support a promising therapeutic strategy of harnessing the eATP generated by standard-of-care chemotherapies to prime the tumor microenvironment for a productive antitumor immune response.</p>","PeriodicalId":18791,"journal":{"name":"Molecular Cancer Therapeutics","volume":" ","pages":"1471-1482"},"PeriodicalIF":5.3,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11443198/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141155622","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Qingsong Guo, Bei Gao, Ruiwen Song, Weinan Li, Shulei Zhu, Qian Xie, Sensen Lou, Lei Wang, Jiafei Shen, Teng Zhao, Yifan Zhang, Jinsong Wu, Wei Lu, Tong Yang
{"title":"FZ-AD005, a Novel DLL3-Targeted Antibody-Drug Conjugate with Topoisomerase I Inhibitor, Shows Potent Antitumor Activity in Preclinical Models.","authors":"Qingsong Guo, Bei Gao, Ruiwen Song, Weinan Li, Shulei Zhu, Qian Xie, Sensen Lou, Lei Wang, Jiafei Shen, Teng Zhao, Yifan Zhang, Jinsong Wu, Wei Lu, Tong Yang","doi":"10.1158/1535-7163.MCT-23-0701","DOIUrl":"10.1158/1535-7163.MCT-23-0701","url":null,"abstract":"<p><p>Delta-like ligand 3 (DLL3) is overexpressed in small cell lung cancer (SCLC) and has been considered an attractive target for SCLC therapy. Rovalpituzumab tesirine was the first DLL3-targeted antibody-drug conjugate (ADC) to enter clinical studies. However, serious adverse events limited progress in the treatment of SCLC with rovalpituzumab tesirine. In this study, we developed a novel DLL3-targeted ADC, FZ-AD005, by using DXd with potent cytotoxicity and a relatively better safety profile to maximize the therapeutic index. FZ-AD005 was generated by a novel anti-DLL3 antibody, FZ-A038, and a valine-alanine (Val-Ala) dipeptide linker to conjugate DXd. Moreover, Fc-silencing technology was introduced in FZ-AD005 to avoid off-target toxicity mediated by FcγRs and showed negligible Fc-mediated effector functions in vitro. In preclinical evaluation, FZ-AD005 exhibited DLL3-specific binding and demonstrated efficient internalization, bystander killing, and excellent in vivo antitumor activities in cell line-derived xenograft and patient-derived xenograft models. FZ-AD005 was stable in circulation with acceptable pharmacokinetic profiles in cynomolgus monkeys. FZ-AD005 was well tolerated in rats and monkeys. The safety profile of FZ-AD005 was favorable, and the highest nonseverely toxic dose was 30 mg/kg in cynomolgus monkeys. In conclusion, FZ-AD005 has the potential to be a superior DLL3-targeted ADC with a wide therapeutic window and is expected to provide clinical benefits for the treatment of patients with SCLC.</p>","PeriodicalId":18791,"journal":{"name":"Molecular Cancer Therapeutics","volume":" ","pages":"1367-1377"},"PeriodicalIF":5.3,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11443207/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141469557","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Gregory L Moore, Veronica G Zeng, Juan E Diaz, Christine Bonzon, Kendra N Avery, Rumana Rashid, Jing Qi, Dong Hyun Nam, Jonathan Jacinto, Matthew A Dragovich, Yoon Kyung Kim, Karen P Balcazar, Charles G Bakhit, Araz Eivazi, Hanh Nguyen, Umesh S Muchhal, David E Szymkowski, John R Desjarlais, Michael Hedvat
{"title":"A B7-H3-targeted CD28 bispecific antibody enhances the activity of anti-PD1 and CD3 T-cell engager immunotherapies.","authors":"Gregory L Moore, Veronica G Zeng, Juan E Diaz, Christine Bonzon, Kendra N Avery, Rumana Rashid, Jing Qi, Dong Hyun Nam, Jonathan Jacinto, Matthew A Dragovich, Yoon Kyung Kim, Karen P Balcazar, Charles G Bakhit, Araz Eivazi, Hanh Nguyen, Umesh S Muchhal, David E Szymkowski, John R Desjarlais, Michael Hedvat","doi":"10.1158/1535-7163.MCT-24-0327","DOIUrl":"https://doi.org/10.1158/1535-7163.MCT-24-0327","url":null,"abstract":"<p><p>T-cell activation is a multistep process requiring T-cell receptor engagement by peptide-major histocompatibility complexes (Signal 1) coupled with CD28-mediated costimulation (Signal 2). Tumors typically lack expression of CD28 ligands, so tumor-specific Signal 1 (e.g., neoepitope presentation) without costimulation may be ineffective or even induce T-cell anergy. We designed the bispecific antibody XmAb808 to co-engage the tumor-associated antigen B7-H3 with CD28 to promote T-cell costimulation within the tumor microenvironment. XmAb808 costimulation was measured by its ability to activate and expand T cells and enhance T cell-mediated cancer cell killing in cocultures of human peripheral blood mononuclear cells (PBMCs) and cancer cells, and in mice engrafted with human PBMCs and tumor xenografts. XmAb808 avidly bound cancer cells and stimulated interleukin (IL)2 and interferon (IFN)γ secretion from T cells cocultured with cancer cells engineered to deliver Signal 1 to T cells via a surface-expressed anti-CD3 antibody. XmAb808 enhanced expression of the anti-apoptotic factor Bcl-xL and CD25, promoting survival and IL2-dependent expansion of T cells coupled with increased T cell-mediated cytotoxicity in vitro. XmAb808 combined with a EpCAM×CD3 bispecific antibody to enhance target cell killing through IL2-dependent expansion of CD25+ T cells. This combination also suppressed pancreatic tumor xenograft growth in mice. Further, XmAb808 combined with an anti-PD1 antibody to suppress breast tumor xenograft growth in mice. XmAb808 as monotherapy and in combination with an anti-PD1 antibody is currently in clinical development in patients with advanced solid tumors. Our results suggest that XmAb808 may also combine with tumor antigen-targeted anti-CD3 (Signal 1) T-cell engagers.</p>","PeriodicalId":18791,"journal":{"name":"Molecular Cancer Therapeutics","volume":" ","pages":""},"PeriodicalIF":5.3,"publicationDate":"2024-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142291431","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ana Martin-Vega,Svetlana A Earnest,Alexander Augustyn,Chonlarat Wichaidit,Luc Girard,Michael Peyton,John D Minna,Jane E Johnson,Melanie H Cobb
{"title":"ASCL1 restrains ERK1/2 to promote survival of a subset of neuroendocrine lung cancers.","authors":"Ana Martin-Vega,Svetlana A Earnest,Alexander Augustyn,Chonlarat Wichaidit,Luc Girard,Michael Peyton,John D Minna,Jane E Johnson,Melanie H Cobb","doi":"10.1158/1535-7163.mct-24-0355","DOIUrl":"https://doi.org/10.1158/1535-7163.mct-24-0355","url":null,"abstract":"The transcription factor achaete-scute complex homolog 1 (ASCL1) is a lineage oncogene that is central in growth and survival of the majority of small cell lung cancers (SCLC) and neuroendocrine non-small cell lung cancers (NSCLC-NE) that express it. Targeting ASCL1, or its downstream pathways, remains a challenge. SCLCs and NSCLC-NE that express ASCL1 exhibit relatively low ERK1/2 activity, in dramatic contrast to NSCLCs in which the ERK pathway has a major role in pathogenesis. ERK1/2 inhibition in ASCL1-expressing lung tumor cells revealed down-regulation of ERK1/2 pathway suppressors SPRY4, SPRED1, DUSP6, and the transcription factor ETV5, which regulates DUSP6. CHIP-seq demonstrated that these genes are bound by ASCL1. Availability of a pharmacological inhibitor directed mechanistic studies towards DUSP6, an ERK1/2-selective phosphatase, in a subset of ASCL1-high NE lung tumors. Inhibition of DUSP6 increased active ERK1/2, which accumulated in the nucleus. Pharmacologic and genetic inhibition of DUSP6 reduced proliferation and survival of these cancers. Resistance developed in DUSP6 KO cells, indicating a bypass mechanism. Although targeting ASCL1 remains a challenge, our findings suggest that expression of ASCL1, DUSP6 and low phospho-ERK1/2 identify neuroendocrine lung cancers for which DUSP6 may be a therapeutic target.","PeriodicalId":18791,"journal":{"name":"Molecular Cancer Therapeutics","volume":"106 1","pages":""},"PeriodicalIF":5.7,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142268794","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Andreas Gollner, Dorothea Rudolph, Ulrike Weyer-Czernilofsky, Rosa Baumgartinger, Peter Jung, Harald Weinstabl, Jürgen Ramharter, Rolf Grempler, Jens Quant, Jörg Rinnenthal, Alejandro Pérez Pitarch, Bojana Golubovic, Daniel Gerlach, Gerd Bader, Kristiane Wetzel, Sebastian Otto, Christian Mandl, Guido Boehmelt, Darryl B. McConnell, Norbert Kraut, Patrizia Sini
{"title":"Discovery and Characterization of Brigimadlin, a Novel and Highly Potent MDM2–p53 Antagonist Suitable for Intermittent Dose Schedules","authors":"Andreas Gollner, Dorothea Rudolph, Ulrike Weyer-Czernilofsky, Rosa Baumgartinger, Peter Jung, Harald Weinstabl, Jürgen Ramharter, Rolf Grempler, Jens Quant, Jörg Rinnenthal, Alejandro Pérez Pitarch, Bojana Golubovic, Daniel Gerlach, Gerd Bader, Kristiane Wetzel, Sebastian Otto, Christian Mandl, Guido Boehmelt, Darryl B. McConnell, Norbert Kraut, Patrizia Sini","doi":"10.1158/1535-7163.mct-23-0783","DOIUrl":"https://doi.org/10.1158/1535-7163.mct-23-0783","url":null,"abstract":"p53 is known as the guardian of the genome and is one of the most important tumor-suppressors. It is inactivated in most tumors, either via tumor protein p53 (TP53) gene mutation or copy number amplification of key negative regulators, e.g., mouse double minute 2 (MDM2). Compounds that bind to the MDM2 protein and disrupt its interaction with p53 restore p53 tumor suppressor activity, thereby promoting cell cycle arrest and apoptosis. Previous clinical experience with MDM2–p53 protein–protein interaction antagonists (MDM2–p53 antagonists) have demonstrated that thrombocytopenia and neutropenia represent on-target dose-limiting toxicities that might restrict their therapeutic utility. Dosing less frequently, while maintaining efficacious exposure, represents an approach to mitigate toxicity and improve the therapeutic window of MDM2–p53 antagonists. However, to achieve this, a molecule possessing excellent potency and ideal pharmacokinetic properties is required. Here, we present the discovery and characterization of brigimadlin (BI 907828), a novel, investigational spiro-oxindole MDM2–p53 antagonist. Brigimadlin exhibited high bioavailability and exposure, as well as dose-linear pharmacokinetics in preclinical models. Brigimadlin treatment restored p53 activity and led to apoptosis induction in preclinical models of TP53 wild-type, MDM2-amplified cancer. Oral administration of brigimadlin in an intermittent dosing schedule induced potent tumor growth inhibition in several TP53 wild-type, MDM2-amplified xenograft models. Exploratory clinical pharmacokinetic studies (NCT03449381) showed high systemic exposure and a long plasma elimination half-life in cancer patients who received oral brigimadlin. These findings support the continued clinical evaluation of brigimadlin in patients with MDM2-amplified cancers, such as dedifferentiated liposarcoma.","PeriodicalId":18791,"journal":{"name":"Molecular Cancer Therapeutics","volume":"22 1","pages":""},"PeriodicalIF":5.7,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142194516","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ji Li, Robyn Clark, Dionysos Slaga, Kendra Avery, Ke Liu, Suzanne Schubbert, Rajat Varma, Eugene Chiang, Klara Totpal, Matthew J Bernett, Patrick G Holder, Teemu T Junttila
{"title":"IL-15/IL-15Rα-Fc-Fusion Protein XmAb24306 Potentiates Activity of CD3 Bispecific Antibodies through Enhancing T-Cell Expansion.","authors":"Ji Li, Robyn Clark, Dionysos Slaga, Kendra Avery, Ke Liu, Suzanne Schubbert, Rajat Varma, Eugene Chiang, Klara Totpal, Matthew J Bernett, Patrick G Holder, Teemu T Junttila","doi":"10.1158/1535-7163.MCT-23-0910","DOIUrl":"10.1158/1535-7163.MCT-23-0910","url":null,"abstract":"<p><p>An insufficient quantity of functional T cells is a likely factor limiting the clinical activity of T-cell bispecific antibodies, especially in solid tumor indications. We hypothesized that XmAb24306 (efbalropendekin alfa), a lymphoproliferative interleukin (IL)-15/IL-15 receptor α (IL-15Rα) Fc-fusion protein, may potentiate the activity of T-cell dependent (TDB) antibodies. The activation of human peripheral T cells by cevostamab, an anti-FcRH5/CD3 TDB, or anti-HER2/CD3 TDB resulted in the upregulation of the IL-2/15Rβ (CD122) receptor subunit in nearly all CD8+ and majority of CD4+ T cells, suggesting that TDB treatment may sensitize T cells to IL-15. XmAb24306 enhanced T-cell bispecific antibody-induced CD8+ and CD4+ T-cell proliferation and expansion. In vitro combination of XmAb24306 with cevostamab or anti-HER2/CD3 TDB resulted in significant enhancement of tumor cell killing, which was reversed when T-cell numbers were normalized, suggesting that T-cell expansion is the main mechanism of the observed benefit. Pretreatment of immunocompetent mice with a mouse-reactive surrogate of XmAb24306 (mIL-15-Fc) resulted in a significant increase of T cells in the blood, spleen, and tumors and converted transient anti-HER2/CD3 TDB responses to complete durable responses. In summary, our results support the hypothesis that the number of tumor-infiltrating T cells is rate limiting for the activity of solid tumor-targeting TDBs. Upregulation of CD122 by TDB treatment and the observed synergy with XmAb24306 and T-cell bispecific antibodies support clinical evaluation of this novel immunotherapy combination.</p>","PeriodicalId":18791,"journal":{"name":"Molecular Cancer Therapeutics","volume":" ","pages":"1305-1316"},"PeriodicalIF":5.3,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140912524","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Chilam Chan, J H Marco Jansen, Ilona S T Hendriks, Ida C van der Peet, Meggy E L Verdonschot, Elsemieke M Passchier, Maria Tsioumpekou, Maaike Nederend, Sharon A Klomp, Thomas Valerius, Matthias Peipp, Jeanette H W Leusen, Patricia A Olofsen
{"title":"Enhancing Neutrophil Cytotoxicity of a Panel of Clinical EGFR Antibodies by Fc Engineering to IgA3.0.","authors":"Chilam Chan, J H Marco Jansen, Ilona S T Hendriks, Ida C van der Peet, Meggy E L Verdonschot, Elsemieke M Passchier, Maria Tsioumpekou, Maaike Nederend, Sharon A Klomp, Thomas Valerius, Matthias Peipp, Jeanette H W Leusen, Patricia A Olofsen","doi":"10.1158/1535-7163.MCT-24-0217","DOIUrl":"10.1158/1535-7163.MCT-24-0217","url":null,"abstract":"<p><p>EGFR plays an essential role in cellular signaling pathways that regulate cell growth, proliferation, and survival and is often dysregulated in cancer. Several monoclonal IgG antibodies have been clinically tested over the years, which exert their function via blocking the ligand binding domain (thereby inhibiting downstream signaling) and inducing Fc-related effector functions, such as antibody-dependent cellular cytotoxicity (ADCC) and antibody-dependent cellular phagocytosis (ADCP). However, these IgG antibodies do not optimally recruit neutrophils, which are the most abundant white blood cell population in humans. Therefore, we reformatted six therapeutic EGFR antibodies (cetuximab, panitumumab, nimotuzumab, necitumumab, zalutumumab, and matuzumab) into the IgA3.0 format, which is an IgA2 isotype adapted for clinical application. Reformatting these antibodies preserved Fab-mediated functions such as EGFR binding, growth inhibition, and ligand blockade. In addition, whole leukocyte ADCC was significantly increased when using this panel of IgA3.0 antibodies compared with their respective IgG counterparts, with no major differences between IgA3.0 antibodies. In vivo, IgA3.0 matuzumab outperformed the other antibodies, resulting in the strongest suppression of tumor outgrowth in a long intraperitoneal model. We showed that neutrophils are important for the suppression of tumor outgrowth. IgA3.0 matuzumab exhibited reduced receptor internalization compared with the other antibodies, possibly accounting for its superior in vivo Fc-mediated tumor cell killing efficacy. In conclusion, reformatting EGFR antibodies into an IgA3.0 format increased Fc-mediated killing while retaining Fab-mediated functions and could therefore be a good alternative for the currently available antibody therapies.</p>","PeriodicalId":18791,"journal":{"name":"Molecular Cancer Therapeutics","volume":" ","pages":"1317-1331"},"PeriodicalIF":5.3,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141492665","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Maria Ioannou, Kriti Lalwani, Abiola A Ayanlaja, Viveka Chinnasamy, Christine A Pratilas, Karisa C Schreck
{"title":"MEK Inhibition Enhances the Antitumor Effect of Radiotherapy in NF1-Deficient Glioblastoma.","authors":"Maria Ioannou, Kriti Lalwani, Abiola A Ayanlaja, Viveka Chinnasamy, Christine A Pratilas, Karisa C Schreck","doi":"10.1158/1535-7163.MCT-23-0510","DOIUrl":"10.1158/1535-7163.MCT-23-0510","url":null,"abstract":"<p><p>Individuals with neurofibromatosis type 1, an autosomal dominant neurogenetic and tumor predisposition syndrome, are susceptible to developing low-grade glioma and less commonly high-grade glioma. These gliomas exhibit loss of the neurofibromin gene [neurofibromin type 1 (NF1)], and 10% to 15% of sporadic high-grade gliomas have somatic NF1 alterations. Loss of NF1 leads to hyperactive RAS signaling, creating opportunity given the established efficacy of MEK inhibitors in plexiform neurofibromas and some individuals with low-grade glioma. We observed that NF1-deficient glioblastoma neurospheres were sensitive to the combination of an MEK inhibitor (mirdametinib) with irradiation, as evidenced by synergistic inhibition of cell growth, colony formation, and increased cell death. In contrast, NF1-intact neurospheres were not sensitive to the combination, despite complete ERK pathway inhibition. No neurosphere lines exhibited enhanced sensitivity to temozolomide combined with mirdametinib. Mirdametinib decreased transcription of homologous recombination genes and RAD51 foci, associated with DNA damage repair, in sensitive models. Heterotopic xenograft models displayed synergistic growth inhibition to mirdametinib combined with irradiation in NF1-deficient glioma xenografts but not in those with intact NF1. In sensitive models, benefits were observed at least 3 weeks beyond the completion of treatment, including sustained phosphor-ERK inhibition on immunoblot and decreased Ki-67 expression. These observations demonstrate synergistic activity between mirdametinib and irradiation in NF1-deficient glioma models and may have clinical implications for patients with gliomas that harbor germline or somatic NF1 alterations.</p>","PeriodicalId":18791,"journal":{"name":"Molecular Cancer Therapeutics","volume":" ","pages":"1261-1272"},"PeriodicalIF":5.3,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11374499/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140876835","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Stacie K Totsch, Andrew S Ishizuka, Kyung-Don Kang, Sam E Gary, Abbey Rocco, Aaron E Fan, Li Zhou, Pablo A Valdes, SeungHo Lee, Jason Li, Luca Peruzzotti-Jametti, Sarah Blitz, Christopher M Garliss, James M Johnston, James M Markert, Geoffrey M Lynn, Joshua D Bernstock, Gregory K Friedman
{"title":"Combination Immunotherapy with Vaccine and Oncolytic HSV Virotherapy Is Time Dependent.","authors":"Stacie K Totsch, Andrew S Ishizuka, Kyung-Don Kang, Sam E Gary, Abbey Rocco, Aaron E Fan, Li Zhou, Pablo A Valdes, SeungHo Lee, Jason Li, Luca Peruzzotti-Jametti, Sarah Blitz, Christopher M Garliss, James M Johnston, James M Markert, Geoffrey M Lynn, Joshua D Bernstock, Gregory K Friedman","doi":"10.1158/1535-7163.MCT-23-0873","DOIUrl":"10.1158/1535-7163.MCT-23-0873","url":null,"abstract":"<p><p>Oncolytic virotherapy or immunovirotherapy is a strategy that utilizes viruses to selectively infect and kill tumor cells while also stimulating an immune response against the tumor. Early clinical trials in both pediatric and adult patients using oncolytic herpes simplex viruses (oHSV) have demonstrated safety and promising efficacy; however, combinatorial strategies designed to enhance oncolysis while also promoting durable T-cell responses for sustaining disease remission are likely required. We hypothesized that combining the direct tumor cell killing and innate immune stimulation by oHSV with a vaccine that promotes T cell-mediated immunity may lead to more durable tumor regression. To this end, we investigated the preclinical efficacy and potential synergy of combining oHSV with a self-assembling nanoparticle vaccine codelivering peptide antigens and Toll-like receptor 7 and 8 agonists (referred to as SNAPvax),which induces robust tumor-specific T-cell immunity. We then assessed how timing of the treatments (i.e., vaccine before or after oHSV) impacts T-cell responses, viral replication, and preclinical efficacy. The sequence of treatments was critical, as survival was significantly enhanced when the SNAPvax vaccine was given prior to oHSV. Increased clinical efficacy was associated with reduced tumor volume and increases in virus replication and tumor antigen-specific CD8+ T cells. These findings substantiate the criticality of combination immunotherapy timing and provide preclinical support for combining SNAPvax with oHSV as a promising treatment approach for both pediatric and adult tumors.</p>","PeriodicalId":18791,"journal":{"name":"Molecular Cancer Therapeutics","volume":" ","pages":"1273-1281"},"PeriodicalIF":5.3,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11374504/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140867304","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}