Notch1 mutation drives clonal expansion in normal esophageal epithelium but impairs tumor growth

NOTCH1 mutant clones occupy the majority of normal human esophagus by middle age, but are comparatively rare in esophageal cancers, suggesting NOTCH1 mutations may promote clonal expansion but impede carcinogenesis. Here we test this hypothesis. Visualizing and sequencing NOTCH1 mutant clones in aging normal human esophagus reveals frequent biallelic mutations that block NOTCH1 signaling. In mouse esophagus, heterozygous Notch1 mutation confers a competitive advantage over wild type cells, an effect enhanced by loss of the second allele. Notch1 loss alters transcription but has minimal effects on epithelial structure and cell dynamics. In a carcinogenesis model, Notch1 mutations were less prevalent in tumors than normal epithelium. Deletion of Notch1 reduced tumor growth, an effect recapitulated by anti-NOTCH1 antibody treatment. We conclude that Notch1 mutations in normal epithelium are beneficial as wild type Notch1 promotes tumor expansion. NOTCH1 blockade may have therapeutic potential in preventing esophageal squamous cancer.

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Knockout of Putative Tumor Suppressor Aldh1l1 in Mice Reprograms Metabolism to Accelerate Growth of Tumors in a Diethylnitrosamine (DEN) Model of Liver Carcinogenesis

Cancers ◽

10.3390/cancers13133219 ◽

2021 ◽

Vol 13 (13) ◽

pp. 3219

Author(s):

Natalia I. Krupenko ◽

Jaspreet Sharma ◽

Halle M. Fogle ◽

Peter Pediaditakis ◽

Kyle C. Strickland ◽

...

Keyword(s):

Tumor Growth ◽

Chemical Carcinogenesis ◽

Dependent Manner ◽

Wild Type ◽

Liver Carcinogenesis ◽

Wild Type Littermate ◽

Tumor Multiplicity ◽

Accelerate Growth ◽

Putative Tumor Suppressor ◽

Formyltetrahydrofolate Dehydrogenase

Cytosolic 10-formyltetrahydrofolate dehydrogenase (ALDH1L1) is commonly downregulated in human cancers through promoter methylation. We proposed that ALDH1L1 loss promotes malignant tumor growth. Here, we investigated the effect of the Aldh1l1 mouse knockout (Aldh1l1−/−) on hepatocellular carcinoma using a chemical carcinogenesis model. Fifteen-day-old male Aldh1l1 knockout mice and their wild-type littermate controls (Aldh1l1+/+) were injected intraperitoneally with 20 μg/g body weight of DEN (diethylnitrosamine). Mice were sacrificed 10, 20, 28, and 36 weeks post-DEN injection, and livers were examined for tumor multiplicity and size. We observed that while tumor multiplicity did not differ between Aldh1l1−/− and Aldh1l1+/+ animals, larger tumors grew in Aldh1l1−/− compared to Aldh1l1+/+ mice at 28 and 36 weeks. Profound differences between Aldh1l1−/− and Aldh1l1+/+ mice in the expression of inflammation-related genes were seen at 10 and 20 weeks. Of note, large tumors from wild-type mice showed a strong decrease of ALDH1L1 protein at 36 weeks. Metabolomic analysis of liver tissues at 20 weeks showed stronger differences in Aldh1l1+/+ versus Aldh1l1−/− metabotypes than at 10 weeks, which underscores metabolic pathways that respond to DEN in an ALDH1L1-dependent manner. Our study indicates that Aldh1l1 knockout promoted liver tumor growth without affecting tumor initiation or multiplicity.

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HGG-26. H3G34V MUTATION AFFECTS GENOMIC H3K36 METHYLATION IN PEDIATRIC GLIOMA

Neuro-Oncology ◽

10.1093/neuonc/noaa222.310 ◽

2020 ◽

Vol 22 (Supplement_3) ◽

pp. iii348-iii348

Author(s):

Tina Huang ◽

Andrea Piunti ◽

Elizabeth Bartom ◽

Jin Qi ◽

Rintaro Hashizume ◽

...

Keyword(s):

Western Blot ◽

Allelic Frequency ◽

Glioma Cell Line ◽

Fluorescent Imaging ◽

Wild Type ◽

Gene Expressions ◽

Pediatric Glioma ◽

Genes Encoding ◽

Normal Human

Abstract BACKGROUND Histone H3.3 mutation (H3F3A) occurs in 50% of cortical pediatric high-grade gliomas. This mutation replaces glycine 34 with arginine or valine (G34R/V), impairing SETD2 activity (H3K36-specific trimethyltransferase), resulting in reduced H3K36me on H3G34V nucleosomes relative to wild-type. This contributes to genomic instability and drives distinct gene expressions associated with tumorigenesis. However, it is not known if this differential H3K36me3 enrichment is due to H3G34V mutant protein alone. Therefore, we set to elucidate the effect of H3G34V on genomic H3K36me3 enrichment in vitro. METHODS Doxycycline-inducible short hairpin RNA (shRNA) against H3F3A was delivered via lentivirus to established H3G34V mutant pediatric glioma cell line KNS42, and H3G34V introduced into H3.3 wild type normal human astrocytes (NHA). Transfections were confirmed by western blot, fluorescent imaging, and flow cytometry, with resulting H3.3WT and H3K36me3 expression determined by western blot. H3.3WT, H3K36me3, and H3G34V ChIP-Seq was performed to evaluate genomic enrichment. RESULTS Complete knockdown of H3G34V was achieved with DOX-induced shRNA, with no change in total H3.3, suggesting disproportionate allelic frequency of genes encoding H3.3 (H3F3A and H3F3B). Modest increase in H3K36me3 occurred after H3F3A-knockdown from KNS42, suggesting H3G34V alone impacts observed H3K36me3 levels. Distinct H3K36me3 genomic enrichment was observed with H3G34V knock-in. CONCLUSIONS We demonstrate that DOX-inducible knockdown of H3F3A in an H3G34V mutant pediatric glioma cells and H3G34V mutation transduction in wild-type astrocytes affects H3K36me3 expression. Further evaluation by ChIP-Seq analysis for restoration of wild-type genomic H3K36me3 enrichment patterns with H3G34V knockdown, and mutant H3K36me3 patterns with H3G34V transduction, is currently underway.

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Molecular and Biochemical Basis of Minocycline-Induced Hyperpigmentation—The Study on Normal Human Melanocytes Exposed to UVA and UVB Radiation

International Journal of Molecular Sciences ◽

10.3390/ijms22073755 ◽

2021 ◽

Vol 22 (7) ◽

pp. 3755

Author(s):

Jakub Rok ◽

Zuzanna Rzepka ◽

Justyna Kowalska ◽

Klaudia Banach ◽

Artur Beberok ◽

...

Keyword(s):

Uv Radiation ◽

Therapeutic Potential ◽

Melanin Synthesis ◽

Uvb Radiation ◽

Biochemical Basis ◽

Skin Hyperpigmentation ◽

Human Melanocytes ◽

Anti Cancer ◽

Normal Human

Minocycline is a drug which induces skin hyperpigmentation. Its frequency reaches up to 50% of treated patients. The adverse effect diminishes the great therapeutic potential of minocycline, including antibacterial, neuroprotective, anti-inflammatory and anti-cancer actions. It is supposed that an elevated melanin level and drug accumulation in melanin-containing cells are related to skin hyperpigmentation. This study aimed to evaluate molecular and biochemical mechanism of minocycline-induced hyperpigmentation in human normal melanocytes, as well as the contribution of UV radiation to this side effect. The experiments involved the evaluation of cyto- and phototoxic potential of the drug using cell imaging with light and confocal microscopes as well as biochemical and molecular analysis of melanogenesis. We showed that minocycline induced melanin synthesis in epidermal melanocytes. The action was intensified by UV irradiation, especially with the UVB spectrum. Minocycline stimulated the expression of microphthalmia-associated transcription factor (MITF) and tyrosinase (TYR) gene. Higher levels of melanin and increased activity of tyrosinase were also observed in treated cells. Moreover, minocycline triggered the supranuclear accumulation of tyrosinase, similar to UV radiation. The decreased level of premelanosome protein PMEL17 observed in all minocycline-treated cultures suggests disorder of the formation, maturation or distribution of melanosomes. The study revealed that minocycline itself was able to enhance melanin synthesis. The action was intensified by irradiation, especially with the UVB spectrum. Demonstrated results confirmed the potential role of melanin and UV radiation minocycline-induced skin hyperpigmentation.

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Identification of Wild-Type and Exon 5 Deletion Variants of Estrogen Receptor β in Normal Human Mammary Gland1

The Journal of Clinical Endocrinology & Metabolism ◽

10.1210/jcem.85.4.6493 ◽

2000 ◽

Vol 85 (4) ◽

pp. 1601-1605 ◽

Cited By ~ 1

Author(s):

Valerie Speirs ◽

Ian P. Adams ◽

David S. Walton ◽

Stephen L. Atkin

Keyword(s):

Estrogen Receptor ◽

Estrogen Receptor Β ◽

Wild Type ◽

Normal Human

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C1013G/CXCR4 acts as a driver mutation of tumor progression and modulator of drug resistance in lymphoplasmacytic lymphoma

Blood ◽

10.1182/blood-2014-03-564583 ◽

2014 ◽

Vol 123 (26) ◽

pp. 4120-4131 ◽

Cited By ~ 122

Author(s):

Aldo M. Roccaro ◽

Antonio Sacco ◽

Cristina Jimenez ◽

Patricia Maiso ◽

Michele Moschetta ◽

...

Keyword(s):

Drug Resistance ◽

Tumor Growth ◽

Tumor Progression ◽

Driver Mutation ◽

Lymphoplasmacytic Lymphoma ◽

Wild Type ◽

Key Points ◽

Activating Mutation

Key Points C1013G/CXCR4 acts as an activating mutation in WM leading to enhanced tumor growth, and as an inducer of drug resistance. BMS936564/MDX1338, a novel anti-CXCR4 moAb, successfully targets WM cells, either C1013G/CXCR4 mutated or wild-type.

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Inhibition of MERTK Promotes Suppression of Tumor Growth in BRAF Mutant and BRAF Wild-Type Melanoma

Molecular Cancer Therapeutics ◽

10.1158/1535-7163.mct-18-0456 ◽

2018 ◽

Vol 18 (2) ◽

pp. 278-288 ◽

Cited By ~ 5

Author(s):

Lenka Sinik ◽

Katherine A. Minson ◽

John J. Tentler ◽

Jacqueline Carrico ◽

Stacey M. Bagby ◽

...

Keyword(s):

Tumor Growth ◽

Wild Type ◽

Braf Mutant

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947 Recombinant myxoma virus MC509-N1 demonstrates antitumor efficacy as monotherapy and in combination with immune checkpoint inhibitors

Journal for ImmunoTherapy of Cancer ◽

10.1136/jitc-2021-sitc2021.947 ◽

2021 ◽

Vol 9 (Suppl 3) ◽

pp. A996-A996

Author(s):

Enkhtaivan Gansukh ◽

Tommy Alain ◽

Tae-Geuk Kim ◽

Ye-Na Namgung ◽

Ka-Yeon Son ◽

...

Keyword(s):

Flow Cytometry ◽

Tumor Microenvironment ◽

Tumor Growth ◽

Immune Checkpoint ◽

Myxoma Virus ◽

Wild Type ◽

Anticancer Efficacy ◽

Immune Profile ◽

Immune State ◽

Inhibition Of Tumor Growth

BackgroundThere are several obstacles to effective cancer immunotherapy including the heterogenic immune profile and the state of the tumor microenvironment. Oncolytic virotherapy provides an opportunity to overcome some of these limitations through high viral replication and the expression of therapeutic transgenes (TGs) within the tumor tissue. Myxoma virus (MYXV) belongs to the family of Poxviridae and represents a potent oncolytic virus and a safe platform as this virus is non-pathogenic in any hosts apart from lagomorphs. Importantly, MYXV has a high capacity of encoding for multiple TG payloads. Here we engineered MC509-N1, a novel double-encoding transgenes (TG1 and TG2) oncolytic MYXV designed for intravenous (IV) injection. The therapeutic TG1 acts to modify and remodel the immune state of the tumor microenvironment, and TG2 allows for prolonged self-evasion from the host immune defense.MethodsTransgenes expression upon infection was detected by ELISA and by flow cytometry. To determine anticancer efficacy, syngeneic B16F10 melanoma or MC38 colorectal cancer-bearing C57BL/6 mice were injected with MC509-N1 intratumorally or IV with or without immune checkpoint inhibitor (ICI). Tumor growth and survival was monitored after treatment and the immune profile within the tumor microenvironment was analyzed by flow cytometry. Mice cured of their tumors from the original treatment were rechallenged with primary tumor cells to examine anticancer immunity.ResultsCells upon infection with MC509-N1 were found to express both transgenes at high levels and stimulate downstream mechanisms. Importantly, the engineering of both transgenes did not affect MC509-N1 infectivity and productivity as compared to wild-type MYXV. Intratumoral injections of MC509-N1 effectively suppressed tumor growth and improved overall survival of both syngeneic cancer models. Furthermore, MC509-N1 therapy effectively modulated the immune profile within the tumor microenvironment, especially the ratio between tumor infiltrated CD8+ cytotoxic T cells and CD4+FoxP3+ T regulatory cells. In addition, IV injections of MC509-N1 showed improved inhibition of tumor growth compared to wild type MYXV. The combination therapy of MC509-N1 with the ICI anti-PD-L1 further promoted inhibition of tumor growth as demonstrated by higher rate of complete regression and improved survival rate. Furthermore, rechallenge experiments revealed that this combination regimen established specific anticancer immune memory and protected from cancer recurrence.ConclusionsOur results demonstrate that the novel engineered MC509-N1 exhibits potent anticancer efficacy, adequately modulates the immune state of the tumor microenvironment, and acts synergistically to eliminate cancer in combination with ICI.

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Polymorphisms in Pilin Glycosylation Locus of Neisseria meningitidis Expressing Class II Pili

Infection and Immunity ◽

10.1128/iai.69.6.3597-3604.2001 ◽

2001 ◽

Vol 69 (6) ◽

pp. 3597-3604 ◽

Cited By ~ 51

Author(s):

Charlene M. Kahler ◽

Larry E. Martin ◽

Yih-Ling Tzeng ◽

Yoon K. Miller ◽

Kerith Sharkey ◽

...

Keyword(s):

Neisseria Meningitidis ◽

Human Serum ◽

Class Ii ◽

Open Reading Frames ◽

Normal Human Serum ◽

Wild Type ◽

Experimental Conditions ◽

Type Iv ◽

Insertional Inactivation ◽

Normal Human

ABSTRACT We have located a locus, pgl, in Neisseria meningitidis strain NMB required for the glycosylation of class II pili. Between five and eight open reading frames (ORFs) (pglF, pglB, pglC, pglB2, orf2, orf3, orf8, and avtA) were present in the pgl clusters of different meningococcal isolates. The Class I pilus-expressing strains Neisseria gonorrhoeae MS11 and N. meningitidis MC58 each contain a pgl cluster in which orf2 andorf3 have been deleted. Strain NMB and other meningococcal isolates which express class II type IV pili contained pglclusters in which pglB had been replaced bypglB2 and an additional novel ORF, orf8, had been inserted between pglB2 and pglC. Insertional inactivation of the eight ORFs of the pglcluster of strain NMB showed that pglF, pglB2, pglC, andpglD, but not orf2, orf3, orf8, andavtA, were necessary for pilin glycosylation. Pilin glycosylation was not essential for resistance to normal human serum, as pglF and pglD mutants retained wild-type levels of serum resistance. Although pglB2 andpglC mutants were significantly sensitive to normal human serum under the experimental conditions used, subsequent examination of the encapsulation phenotypes revealed that pglB2 andpglC mutants expressed almost 50% less capsule than wild-type NMB. A mutation in orf3, which did not affect pilin glycosylation, also resulted in a 10% reduction in capsule expression and a moderately serum sensitive phenotype. On the basis of these results we suggest that pilin glycosylation may proceed via a lipid-linked oligosaccharide intermediate and that blockages in this pathway may interfere with capsular transport or assembly.

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