{"title":"Non-classical action of Ku70 promotes Treg suppressive function through a FOXP3-dependent mechanism in lung adenocarcinoma.","authors":"Qianru Huang,Na Tian,Jianfeng Zhang,Shiyang Song,Hao Cheng,Xinnan Liu,Wenle Zhang,Youqiong Ye,Yanhua Du,Xueyu Dai,Rui Liang,Dan Li,Sheng-Ming Dai,Chuan Wang,Zhi Chen,Qianjun Zhou,Bin Li","doi":"10.1172/jci178079","DOIUrl":"https://doi.org/10.1172/jci178079","url":null,"abstract":"Ku70, a DNA repair protein, binds to the damaged DNA ends and orchestrates the recruitment of other proteins to facilitate repair of DNA double-strand breaks. Besides its essential role in DNA repair, several studies have highlighted non-classical functions of Ku70 in cellular processes. However, its function in immune homeostasis and anti-tumor immunity remains unknown. Here, we discovered a marked association between elevated Ku70 expression and unfavorable prognosis in lung adenocarcinoma, focusing specifically on increased Ku70 levels in tumor-infiltrated Treg cells. Using a lung-colonizing tumor model of in mice with Treg-specific Ku70 deficiency, we demonstrated that deletion of Ku70 in Treg cells led to a stronger anti-tumor response and slower tumor growth due to impaired immune-suppressive capacity of Treg cells. Furthermore, we confirmed that Ku70 played a critical role in sustaining the suppressive function of human Treg cells. We found that Ku70 bound to FOXP3 and occupied FOXP3-bound genomic sites to support its transcriptional activities. These findings not only unveil a non-homologous end joining (NHEJ)-independent role of Ku70 crucial for Treg suppressive function, but also underscore the potential of targeting Ku70 as an effective strategy in cancer therapy, aiming to both restrain cancer cells and enhance pulmonary anti-tumor immunity.","PeriodicalId":520097,"journal":{"name":"The Journal of Clinical Investigation","volume":"168 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142490552","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yurong Song,Ryan N Baugher,Todd B Young,Brandon Somerville,Yuriko Mori,Ligia A Pinto,Kim E Nichols,Robert H Shoemaker
{"title":"Frameshift mutation spectra overlap between constitutional mismatch repair deficiency tumors and Lynch syndrome tumors.","authors":"Yurong Song,Ryan N Baugher,Todd B Young,Brandon Somerville,Yuriko Mori,Ligia A Pinto,Kim E Nichols,Robert H Shoemaker","doi":"10.1172/jci185999","DOIUrl":"https://doi.org/10.1172/jci185999","url":null,"abstract":"","PeriodicalId":520097,"journal":{"name":"The Journal of Clinical Investigation","volume":"234 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142488295","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jiawei Wang,Huogang Wang,Wei Zhou,Xin Luo,Huijuan Wang,Qing Meng,Jiaxin Chen,Xiaoyu Chen,Yinqiang Liu,David W Chan,Zhenyu Ju,Zhangfa Song
{"title":"MOGAT3-Mediated DAG Accumulation Drives Acquired Resistance to Anti-BRAF/EGFR Therapy in BRAFV600E-Mutant Metastatic Colorectal Cancer.","authors":"Jiawei Wang,Huogang Wang,Wei Zhou,Xin Luo,Huijuan Wang,Qing Meng,Jiaxin Chen,Xiaoyu Chen,Yinqiang Liu,David W Chan,Zhenyu Ju,Zhangfa Song","doi":"10.1172/jci182217","DOIUrl":"https://doi.org/10.1172/jci182217","url":null,"abstract":"BRAFV600E-mutant metastatic colorectal cancer (mCRC) is associated with poor prognosis. The combination of anti-BRAF/EGFR (encorafenib/cetuximab) treatment for patients with BRAFV600E-mutant mCRC improved clinical benefits; unfortunately, inevitable acquired resistance limits the treatment outcome, and the mechanism has not been validated. Here, we discovered that monoacylglycerol O-Acyltransferase 3 (MOGAT3) mediated diacylglycerol (DAG) accumulation contributed to acquired resistance to encorafenib/cetuximab by dissecting BRAFV600E-mutant mCRC patient-derived xenograft (PDX) model exposed to encorafenib/cetuximab administration. Mechanistically, upregulated MOGAT3 promotes DAG synthesis and reduces fatty acid oxidation (FAO)-promoting DAG accumulation and activating PKCα-CRAF-MEK-ERK, driving acquired resistance. Resistance-induced hypoxia promotes MOGAT3 transcriptional elevation; simultaneously, MOGAT3-mediated DAG accumulation increases HIF1A expression in translation level through PKCα-CRAF-eIF4E activation, strengthening the resistance status. Intriguingly, reducing intratumoral DAG by fenofibrate or Pf-06471553 restores the antitumor efficacy of encorafenib/cetuximab on resistant BRAFV600E-mutant mCRC, interrupted PKCα-CRAF-MEK-ERK signaling. These findings reveal the critical metabolite DAG as a modulator of encorafenib/cetuximab efficacy in BRAFV600E-mutant mCRC, suggesting that fenofibrate may prove beneficial for resistant BRAFV600E-mutant mCRC patients.","PeriodicalId":520097,"journal":{"name":"The Journal of Clinical Investigation","volume":"63 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142488296","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ru M Wen,Jessica C Stark,G Edward W Marti,Zenghua Fan,Aram Lyu,Fernando Jose Garcia Marques,Xiangyue Zhang,Nicholas M Riley,Sarah M Totten,Abel Bermudez,Rosalie Nolley,Hongjuan Zhao,Lawrence Fong,Edgar G Engleman,Sharon J Pitteri,Carolyn R Bertozzi,James D Brooks
{"title":"Sialylated glycoproteins suppress immune cell killing by binding to Siglec-7 and Siglec-9 in prostate cancer.","authors":"Ru M Wen,Jessica C Stark,G Edward W Marti,Zenghua Fan,Aram Lyu,Fernando Jose Garcia Marques,Xiangyue Zhang,Nicholas M Riley,Sarah M Totten,Abel Bermudez,Rosalie Nolley,Hongjuan Zhao,Lawrence Fong,Edgar G Engleman,Sharon J Pitteri,Carolyn R Bertozzi,James D Brooks","doi":"10.1172/jci180282","DOIUrl":"https://doi.org/10.1172/jci180282","url":null,"abstract":"Prostate cancer is the second leading cause of male cancer death in the U.S. Current immune checkpoint inhibitor-based immunotherapies have improved survival for many malignancies; however, they have failed to prolong survival for prostate cancer. Siglecs (sialic acid-binding immunoglobulin-like lectins) are expressed on immune cells and regulate immune responses and function. Siglec-7 and Siglec-9 contribute to immune evasion by interacting with their ligands. However, the role of Siglec-7/9 receptors and their ligands in prostate cancer remains poorly understood. Here, we find that Siglec-7 and Siglec-9 are associated with poor prognosis in prostate cancer patients, and are highly expressed in myeloid cells, including macrophages, in prostate tumor tissues. Siglecs-7 and -9 ligands were expressed in prostate cancer cells and human prostate tumor tissues. Blocking the interactions between Siglec-7/9 and sialic acids inhibited prostate cancer xenograft growth and increased immune cell infiltration in humanized mice in vivo. Using a CRISPRi screen and mass spectrometry, we identified CD59 as a candidate Siglec-9 ligand in prostate cancer. The identification of Siglecs-7 and -9 as potential therapeutic targets, including CD59/Siglec-9 axis, opens up opportunities for immune-based interventions in prostate cancer.","PeriodicalId":520097,"journal":{"name":"The Journal of Clinical Investigation","volume":"51 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142488298","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Laura Ondrisova,Vaclav Seda,Krystof Hlavac,Petra Pavelkova,Eva Hoferkova,Giorgia Chiodin,Lenka Kostalova,Gabriela Mladonicka Pavlasova,Daniel Filip,Josef Vecera,Pedro Faria Zeni,Jan Oppelt,Zuzana Kahounova,Rachel Vichova,Karel Soucek,Anna Panovska,Karla Plevova,Sarka Pospisilova,Martin Simkovic,Filip Vrbacky,Daniel Lysak,Stacey M Fernandes,Matthew S Davids,Alba Maiques-Diaz,Stella Charalampopoulou,Jose I Martin-Subero,Jennifer R Brown,Michael Doubek,Francesco Forconi,Jiri Mayer,Marek Mraz
{"title":"FoxO1/Rictor axis induces a non-genetic adaptation to Ibrutinib via Akt activation in chronic lymphocytic leukemia.","authors":"Laura Ondrisova,Vaclav Seda,Krystof Hlavac,Petra Pavelkova,Eva Hoferkova,Giorgia Chiodin,Lenka Kostalova,Gabriela Mladonicka Pavlasova,Daniel Filip,Josef Vecera,Pedro Faria Zeni,Jan Oppelt,Zuzana Kahounova,Rachel Vichova,Karel Soucek,Anna Panovska,Karla Plevova,Sarka Pospisilova,Martin Simkovic,Filip Vrbacky,Daniel Lysak,Stacey M Fernandes,Matthew S Davids,Alba Maiques-Diaz,Stella Charalampopoulou,Jose I Martin-Subero,Jennifer R Brown,Michael Doubek,Francesco Forconi,Jiri Mayer,Marek Mraz","doi":"10.1172/jci173770","DOIUrl":"https://doi.org/10.1172/jci173770","url":null,"abstract":"BTK inhibitor therapy induces peripheral blood lymphocytosis in chronic lymphocytic leukemia (CLL) lasting for several months. It remains unclear whether non-genetic adaptation mechanisms exist, allowing CLL cells' survival during BTK inhibitor-induced lymphocytosis and/or playing a role in therapy resistance. We show that in approximately 70 % of CLL cases, ibrutinib treatment in vivo increases Akt activity above pre-therapy levels within several weeks, leading to compensatory CLL cell survival and a more prominent lymphocytosis on therapy. Ibrutinib-induced Akt phosphorylation (pAktS473) is caused by the upregulation of FoxO1 transcription factor, which induces expression of Rictor, an assembly protein for mTORC2 protein complex that directly phosphorylates Akt at serine 473 (S473). Knock-out or inhibition of FoxO1 or Rictor led to a dramatic decrease in Akt phosphorylation and growth disadvantage for malignant B cells in the presence of ibrutinib (or PI3K inhibitor idelalisib) in vitro and in vivo. FoxO1/Rictor/pAktS473 axis represents an early non-genetic adaptation to BCR inhibitor therapy not requiring PI3Kδ or BTK kinase activity. We further demonstrate that FoxO1 can be targeted therapeutically, and its inhibition induces CLL cells' apoptosis alone or in combination with BTK inhibitors (ibrutinib, acalabrutinib, pirtobrutinib) and blocks their proliferation triggered by T-cell factors (CD40L, IL-4, and IL-21).","PeriodicalId":520097,"journal":{"name":"The Journal of Clinical Investigation","volume":"17 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142488299","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Allison Joy Nielsen,Gabriella Kyra Albert,Amelia Sanchez,Jiangli Chen,Jing Liu,Andres Sebastian Davalos,Degui Geng,Xander G Bradeen,Jennifer D Hintzsche,William Robinson,Martin McCarter,Carol M Amato,Richard Tobin,Kasey L Couts,Breelyn Ann Wilky,Eduardo Davila
{"title":"DNA-PK inhibition enhances neoantigen diversity and increases T cell responses to immunoresistant tumors.","authors":"Allison Joy Nielsen,Gabriella Kyra Albert,Amelia Sanchez,Jiangli Chen,Jing Liu,Andres Sebastian Davalos,Degui Geng,Xander G Bradeen,Jennifer D Hintzsche,William Robinson,Martin McCarter,Carol M Amato,Richard Tobin,Kasey L Couts,Breelyn Ann Wilky,Eduardo Davila","doi":"10.1172/jci180278","DOIUrl":"https://doi.org/10.1172/jci180278","url":null,"abstract":"Effective antitumor T cell activity relies on the expression and MHC presentation of tumor neoantigens. Tumor cells can evade T cell detection by silencing the transcription of antigens or by altering MHC machinery resulting in inadequate neoantigen-specific T cell activation. We identified DNA-PK inhibitor (DNA-PKi) NU7441 as a promising immunomodulator that reduced immunosuppressive proteins while increasing MHC-I expression in a panel of human melanoma cell lines. In tumor-bearing mice, combination therapy using NU7441 and immune adjuvants STING ligand and CD40 agonist (NU-SL40) substantially increased and diversified the neoantigen landscape, antigen presenting machinery, and consequently substantially increased both the number and repertoire of neoantigen-reactive tumor infiltrating lymphocytes (TILs). DNA-PK-inhibition or knockout promoted transcription and protein expression of various neoantigens in human and mouse melanomas and induced sensitivity to ICB in resistant tumors. In patients, PRKDC levels inversely correlated with MHC I expression and CD8 TILs but positively correlated with increased neoantigen loads and improved responses to ICB. These studies suggest that inhibiting DNA-PK activity can restore tumor immunogenicity by increasing neoantigen expression and presentation and broadening the neoantigen-reactive T cell population.","PeriodicalId":520097,"journal":{"name":"The Journal of Clinical Investigation","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142488302","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ye Ji Choi,Gabriel Richard,Guanshi Zhang,Jeffrey B Hodgin,Dawit S Demeke,Yingbao Yang,Jennifer A Schaub,Ian M Tamayo,Bhupendra K Gurung,Abhijit S Naik,Viji Nair,Carissa Birznieks,Alexis MacDonald,Phoom Narongkiatikhun,Susan Gross,Lynette Driscoll,Maureen Flynn,Kalie Tommerdahl,Kristen J Nadeau,Viral N Shah,Tim Vigers,Janet K Snell-Bergeon,Jessica Kendrick,Daniel H van Raalte,Lu-Ping Li,Pottumarthi Prasad,Patricia Ladd,Bennett B Chin,David Z Cherney,Phillip J McCown,Fadhl Alakwaa,Edgar A Otto,Frank C Brosius,Pierre Jean Saulnier,Victor G Puelles,Jesse A Goodrich,Kelly Street,Manjeri A Venkatachalam,Aaron Ruiz,Ian H de Boer,Robert G Nelson,Laura Pyle,Denis P Blondin,Kumar Sharma,Matthias Kretzler,Petter Bjornstad
{"title":"Attenuated kidney oxidative metabolism in young adults with type 1 diabetes.","authors":"Ye Ji Choi,Gabriel Richard,Guanshi Zhang,Jeffrey B Hodgin,Dawit S Demeke,Yingbao Yang,Jennifer A Schaub,Ian M Tamayo,Bhupendra K Gurung,Abhijit S Naik,Viji Nair,Carissa Birznieks,Alexis MacDonald,Phoom Narongkiatikhun,Susan Gross,Lynette Driscoll,Maureen Flynn,Kalie Tommerdahl,Kristen J Nadeau,Viral N Shah,Tim Vigers,Janet K Snell-Bergeon,Jessica Kendrick,Daniel H van Raalte,Lu-Ping Li,Pottumarthi Prasad,Patricia Ladd,Bennett B Chin,David Z Cherney,Phillip J McCown,Fadhl Alakwaa,Edgar A Otto,Frank C Brosius,Pierre Jean Saulnier,Victor G Puelles,Jesse A Goodrich,Kelly Street,Manjeri A Venkatachalam,Aaron Ruiz,Ian H de Boer,Robert G Nelson,Laura Pyle,Denis P Blondin,Kumar Sharma,Matthias Kretzler,Petter Bjornstad","doi":"10.1172/jci183984","DOIUrl":"https://doi.org/10.1172/jci183984","url":null,"abstract":"BACKGROUNDIn type 1 diabetes (T1D), impaired insulin sensitivity may contribute to the development of diabetic kidney disease (DKD) through alterations in kidney oxidative metabolism.METHODSYoung adults with T1D (n = 30) and healthy controls (HC, n = 20) underwent hyperinsulinemic-euglycemic clamp studies, MRI, 11C-acetate PET, kidney biopsies, single-cell RNA sequencing, and spatial metabolomics to assess this relationship.RESULTSParticipants with T1D had significantly higher glomerular basement membrane thickness compared to HC. T1D participants exhibited lower insulin sensitivity and cortical oxidative metabolism, correlating with higher insulin sensitivity. Proximal tubular transcripts of TCA cycle and oxidative phosphorylation enzymes were lower in T1D. Spatial metabolomics showed reductions in tubular TCA cycle intermediates, indicating mitochondrial dysfunction. The Slingshot algorithm identified a lineage of proximal tubular cells progressing from stable to adaptive/maladaptive subtypes, using pseudotime trajectory analysis, which computationally orders cells along a continuum of states. This analysis revealed distinct distribution patterns between T1D and HC, with attenuated oxidative metabolism in T1D attributed to a greater proportion of adaptive/maladaptive subtypes with low expression of TCA cycle and oxidative phosphorylation transcripts. Pseudotime progression associated with higher HbA1c, BMI, GBM, and lower insulin sensitivity and cortical oxidative metabolism.CONCLUSIONThese early structural and metabolic changes in T1D kidneys may precede clinical DKD.TRIAL REGISTRATIONCLINICALTRIALSgov NCT04074668.","PeriodicalId":520097,"journal":{"name":"The Journal of Clinical Investigation","volume":"67 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142488301","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Saiti S Halder,Michael J Rynkiewicz,Lynne Kim,Meaghan Barry,Ahmed Ga Zied,Lorenzo R Sewanan,Jonathan A Kirk,Jeffrey R Moore,William Lehman,Stuart G Campbell
{"title":"Distinct mechanisms drive divergent phenotypes in hypertrophic and dilated cardiomyopathy associated TPM1 variants.","authors":"Saiti S Halder,Michael J Rynkiewicz,Lynne Kim,Meaghan Barry,Ahmed Ga Zied,Lorenzo R Sewanan,Jonathan A Kirk,Jeffrey R Moore,William Lehman,Stuart G Campbell","doi":"10.1172/jci179135","DOIUrl":"https://doi.org/10.1172/jci179135","url":null,"abstract":"Hypertrophic and dilated cardiomyopathies (HCM and DCM, respectively) are inherited disorders that may be caused by mutations to the same sarcomeric protein but have completely different clinical phenotypes. The precise mechanisms by which point mutations within the same gene bring about phenotypic diversity remain unclear. Our objective has been to develop a mechanistic explanation of diverging phenotypes in two TPM1 mutations, E62Q (HCM) and E54K (DCM). Drawing on data from the literature and experiments with stem cell-derived cardiomyocytes expressing the TPM1 mutations of interest, we constructed computational simulations that provide plausible explanations of the distinct muscle contractility caused by each variant. In E62Q, increased calcium sensitivity and hypercontractility was explained most accurately by a reduction in effective molecular stiffness of tropomyosin and alterations in its interactions with the actin thin filament that favor the 'closed' regulatory state. By contrast, the E54K mutation appeared to act via long-range allosteric interactions to increase the association rate of the C-terminal troponin I mobile domain to tropomyosin/actin. These mutation-linked molecular events produced diverging alterations in gene expression that can be observed in human engineered heart tissues. Modulators of myosin activity confirmed our proposed mechanisms by rescuing normal contractile behavior in accordance with predictions.","PeriodicalId":520097,"journal":{"name":"The Journal of Clinical Investigation","volume":"234 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142488300","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ting-Yu Chang,Yan Yan,Zih-Yao Yu,Moeez Rathore,Nian-Zhe Lee,Hui-Ju Tseng,Li-Hsin Cheng,Wei-Jan Huang,Wei Zhang,Ernest R Chan,Yulan Qing,Ming-Lun Kang,Rui Wang,Kelvin K Tsai,John J Pink,William E Harte,Stanton L Gerson,Sung-Bau Lee
{"title":"Combined HDAC8 and checkpoint kinase inhibition induces tumor-selective synthetic lethality in preclinical models.","authors":"Ting-Yu Chang,Yan Yan,Zih-Yao Yu,Moeez Rathore,Nian-Zhe Lee,Hui-Ju Tseng,Li-Hsin Cheng,Wei-Jan Huang,Wei Zhang,Ernest R Chan,Yulan Qing,Ming-Lun Kang,Rui Wang,Kelvin K Tsai,John J Pink,William E Harte,Stanton L Gerson,Sung-Bau Lee","doi":"10.1172/jci165448","DOIUrl":"https://doi.org/10.1172/jci165448","url":null,"abstract":"The elevated level of replication stress is an intrinsic characteristic of cancer cells. Targeting the mechanisms that maintain genome stability to further increase replication stress and thus induce severe genome instability has become a promising approach for cancer treatment. Here, we identify histone deacetylase 8 (HDAC8) as a drug target whose inactivation synergizes with the inhibition of checkpoint kinases to elicit substantial replication stress and compromise genome integrity selectively in cancer cells. We showed that simultaneous inhibition of HDAC8 and checkpoint kinases led to extensive replication fork collapse, irreversible cell-cycle arrest, and synergistic vulnerability in various cancer cells. The efficacy of the combination treatment was further validated in patient tumor-derived organoid (PDO) and xenograft mouse (PDX) models, providing important insights into patient-specific drug responses. Our data revealed that HDAC8 activity was essential for reducing the acetylation level of structural maintenance of chromosomes protein 3 (SMC3) ahead of replication forks and preventing R loop formation. HDAC8 inactivation resulted in slowed fork progression and checkpoint kinase activation. Our findings indicate that HDAC8 guards the integrity of the replicating genome, and the cancer-specific synthetic lethality between HDAC8 and checkpoint kinases provides a promising replication stress-targeting strategy for treating a broad range of cancers.","PeriodicalId":520097,"journal":{"name":"The Journal of Clinical Investigation","volume":"2 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142488297","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Antwi-Boasiako Oteng,Liu Liu,Yinghong Cui,Oksana Gavrilova,Huiyan Lu,Min Chen,Lee S Weinstein,Jonathan E Campbell,Jo E Lewis,Fiona M Gribble,Frank Reimann,Jürgen Wess
{"title":"Activation of Gs signaling in mouse enteroendocrine K-cells greatly improves obesity- and diabetes-related metabolic deficits.","authors":"Antwi-Boasiako Oteng,Liu Liu,Yinghong Cui,Oksana Gavrilova,Huiyan Lu,Min Chen,Lee S Weinstein,Jonathan E Campbell,Jo E Lewis,Fiona M Gribble,Frank Reimann,Jürgen Wess","doi":"10.1172/jci182325","DOIUrl":"https://doi.org/10.1172/jci182325","url":null,"abstract":"Following a meal, glucagon-like peptide-1 (GLP1) and glucose-dependent insulinotropic polypeptide (GIP), the two major incretins promoting insulin release, are secreted from specialized enteroendocrine cells (L- and K-cells, respectively). Although GIP is the dominant incretin in humans, the detailed molecular mechanisms governing its release remain to be explored. GIP secretion is regulated by the activity of G protein-coupled receptors (GPCRs) expressed by K-cells. GPCRs couple to one or more specific classes of heterotrimeric G proteins. In the present study, we focused on the potential metabolic roles of K-cell Gs. First, we generated a mouse model that allowed us to selectively stimulate K-cell Gs signaling. Second, we generated a mouse strain harboring an inactivating mutation of Gnas, the gene encoding the alpha-subunit of Gs, selectively in K-cells. Metabolic phenotyping studies showed that acute or chronic stimulation of K-cell Gs signaling greatly improved impaired glucose homeostasis in obese mice and in a mouse model of type 2 diabetes, due to enhanced GIP secretion. In contrast, K-cell-specific Gnas knockout mice displayed markedly reduced plasma GIP levels. These data strongly suggest that strategies aimed at enhancing K-cell Gs signaling may prove useful for the treatment of diabetes and related metabolic diseases.","PeriodicalId":520097,"journal":{"name":"The Journal of Clinical Investigation","volume":"60 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142488303","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}