Lentivirus vector‑mediated genetic manipulation of oncogenic pathways induces tumor formation in rabbit brain

SUMMARYMajority of cancers harbor alterations of the tumor suppressor TP53. However, childhood cancers, including unfavorable neuroblastoma, often lack TP53 mutations despite frequent loss of p53 function, suggesting alternative p53 inactivating mechanisms.Here we show that p53-regulating PPM1D at chromosome 17q22.3 is linked to aggressive tumors and poor prognosis in neuroblastoma. We identified that WIP1-phosphatase encoded by PPM1D, is activated by frequent segmental 17q-gain further accumulated during clonal evolution, gene-amplifications, gene-fusions or gain-of-function somatic and germline mutations. Pharmacological and genetic manipulation established WIP1 as a druggable target in neuroblastoma. Genome-scale CRISPR-Cas9 screening demonstrated PPM1D genetic dependency in TP53 wild-type neuroblastoma cell lines, and shRNA PPM1D knockdown significantly delayed in vivo tumor formation. Establishing a transgenic mouse model overexpressing PPM1D showed that these mice develop cancers phenotypically and genetically similar to tumors arising in mice with dysfunctional p53 when subjected to low-dose irradiation. Tumors include T-cell lymphomas harboring Notch1-mutations, Pten-deletions and p53-accumulation, adenocarcinomas and PHOX2B-expressing neuroblastomas establishing PPM1D as a bona fide oncogene in wtTP53 cancer and childhood neuroblastoma. Pharmacological inhibition of WIP1 suppressed the growth of neural tumors in nude mice proposing WIP1 as a therapeutic target in neural childhood tumors.

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Altered copper homeostasis underlies sensitivity of hepatocellular carcinoma to copper chelation

Metallomics ◽

10.1039/d0mt00156b ◽

2020 ◽

Author(s):

Caroline I. Davis ◽

Xingxing Gu ◽

Ryan M. Kiefer ◽

Martina Ralle ◽

Terence P. Gade ◽

...

Keyword(s):

Hepatocellular Carcinoma ◽

Genetic Manipulation ◽

Copper Homeostasis ◽

Glycolytic Metabolism ◽

Copper Chelation ◽

Oncogenic Pathways ◽

Pharmacologic Inhibition

Bioavailable Cu fuels oncogenic pathways that drive tumorigenesis. Intriguingly, genetic manipulation or pharmacologic inhibition of intracellular Cu diminishes hypoxia-induced glycolytic metabolism and attenuates HCC tumorigenic properties.

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L1CAM promotes ovarian cancer stemness and tumor initiation via FGFR1/SRC/STAT3 signaling

Journal of Experimental & Clinical Cancer Research ◽

10.1186/s13046-021-02117-z ◽

2021 ◽

Vol 40 (1) ◽

Author(s):

Marco Giordano ◽

Alessandra Decio ◽

Chiara Battistini ◽

Micol Baronio ◽

Fabrizio Bianchi ◽

...

Keyword(s):

Molecular Mechanisms ◽

Genetic Manipulation ◽

Tumor Formation ◽

In Vitro Assays ◽

Tumor Initiation ◽

Loss Of Function ◽

Stat3 Signaling

Abstract Background Cancer stem cells (CSC) have been implicated in tumor progression. In ovarian carcinoma (OC), CSC drive tumor formation, dissemination and recurrence, as well as drug resistance, thus contributing to the high death-to-incidence ratio of this disease. However, the molecular basis of such a pathogenic role of ovarian CSC (OCSC) has been elucidated only to a limited extent. In this context, the functional contribution of the L1 cell adhesion molecule (L1CAM) to OC stemness remains elusive. Methods The expression of L1CAM was investigated in patient-derived OCSC. The genetic manipulation of L1CAM in OC cells provided gain and loss-of-function models that were then employed in cell biological assays as well as in vivo tumorigenesis experiments to assess the role of L1CAM in OC cell stemness and in OCSC-driven tumor initiation. We applied antibody-mediated neutralization to investigate L1CAM druggability. Biochemical approaches were then combined with functional in vitro assays to study the molecular mechanisms underlying the functional role of L1CAM in OCSC. Results We report that L1CAM is upregulated in patient-derived OCSC. Functional studies showed that L1CAM promotes several stemness-related properties in OC cells, including sphere formation, tumor initiation and chemoresistance. These activities were repressed by an L1CAM-neutralizing antibody, pointing to L1CAM as a druggable target. Mechanistically, L1CAM interacted with and activated fibroblast growth factor receptor-1 (FGFR1), which in turn induced the SRC-mediated activation of STAT3. The inhibition of STAT3 prevented L1CAM-dependent OC stemness and tumor initiation. Conclusions Our study implicate L1CAM in the tumorigenic function of OCSC and point to the L1CAM/FGFR1/SRC/STAT3 signaling pathway as a novel driver of OC stemness. We also provide evidence that targeting this pathway can contribute to OC eradication.

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PARP1 Inhibitor Combined With Oxaliplatin Efficiently Suppresses Oxaliplatin Resistance in Gastric Cancer-Derived Organoids via Homologous Recombination and the Base Excision Repair Pathway

Frontiers in Cell and Developmental Biology ◽

10.3389/fcell.2021.719192 ◽

2021 ◽

Vol 9 ◽

Author(s):

Huafu Li ◽

Chunming Wang ◽

Linxiang Lan ◽

Wenhui Wu ◽

Ian Evans ◽

...

Keyword(s):

Gastric Cancer ◽

Homologous Recombination ◽

Base Excision Repair ◽

Genetic Manipulation ◽

Excision Repair ◽

Tumor Formation ◽

Parp Inhibition ◽

Repair Pathway ◽

Base Excision Repair Pathway ◽

Base Excision

Oxaliplatin (OXA) resistance in the treatment of different types of cancer is an important and complex problem. The culture of tumor organoids derived from gastric cancer can help us to provide a deeper understanding of the underlying mechanisms that lead to OXA resistance. In this study, our purpose was to understand the mechanisms that lead to OXA resistance, and to provide survival benefits to patients with OXA through targeted combination therapies. Using sequence analysis of OXA-resistant and non-OXA-resistant organoids, we found that PARP1 is an important gene that mediates OXA resistance. Through the patients’ follow-up data, it was observed that the expression level of PARP1 was significantly correlated with OXA resistance. This was confirmed by genetic manipulation of PARP1 expression in OXA-resistant organoids used in subcutaneous tumor formation. Results further showed that PARP1 mediated OXA resistance by inhibiting the base excision repair pathway. OXA also inhibited homologous recombination by CDK1 activity and importantly made cancers with normal BRCA1 function sensitive to PARP inhibition. As a result, combination of OXA and Olaparib (PARP-1/2/3 inhibitor), inhibited in vivo and in vitro OXA resistant organoid growth and viability.

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A 16q22.1 variant confers susceptibility to colorectal cancer as a distal regulator of ZFP90

Oncogene ◽

10.1038/s41388-019-1055-4 ◽

2019 ◽

Vol 39 (6) ◽

pp. 1347-1360

Author(s):

Chen-Yang Yu ◽

Ji-Xuan Han ◽

Junfang Zhang ◽

Penglei Jiang ◽

Chaoqin Shen ◽

...

Keyword(s):

Colorectal Cancer ◽

Genetic Manipulation ◽

Association Studies ◽

Transcript Level ◽

Causal Variant ◽

Genome Wide Association Studies ◽

Single Nucleotide ◽

Enhancer Element ◽

Oncogenic Pathways ◽

Genome Wide

Abstract Genome-wide association studies (GWASs) implicate 16q22.1 locus in risk for colorectal cancer (CRC). However, the underlying oncogenic mechanisms remain unknown. Here, through comprehensive filtration, we prioritized rs7198799, a common SNP in the second intron of the CDH1, as the putative causal variant. In addition, we found an association of CRC-risk allele C of rs7198799 with elevated transcript level of biological plausible candidate gene ZFP90 via expression quantitative trait loci analysis. Mechanistically, causal variant rs7198799 resides in an enhancer element and remotely regulate ZFP90 expression by targeting the transcription factor NFATC2. Remarkably, CRISPR/Cas9-guided single-nucleotide editing demonstrated the direct effect of rs7198799 on ZFP90 expression and CRC cellular malignant phenotype. Furthermore, ZFP90 affects several oncogenic pathways, including BMP4, and promotes carcinogenesis in patients and in animal models with ZFP90 specific genetic manipulation. Taken together, these findings reveal a risk SNP-mediated long-range regulation on the NFATC2-ZFP90-BMP4 pathway underlying the initiation of CRC.

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Inflammatory breast cancer remains the most aggressive form of breast cancer. A multimodality therapeutic plan has shown improved survival results

10.31219/osf.io/cr935 ◽

2021 ◽

Author(s):

Moataz Dowaidar

Keyword(s):

Breast Cancer ◽

Inflammatory Breast Cancer ◽

Locally Advanced ◽

Tumor Formation ◽

Novel Therapy ◽

Acquired Drug Resistance ◽

Future Studies ◽

Aggressive Form ◽

Oncogenic Pathways ◽

Therapy Strategies

Even though inflammatory breast cancer remains the most aggressive form of breast cancer, with the highest rates of morbidity and mortality, other types of breast cancer do exist. In addition to Nneoadjuvant chemotherapy, surgery, and radiation, a multimodality therapeutic plan including these procedures has shown improved survival results for locally advanced disease. Most current research focuses on finding new and novel therapy strategies that can allow people with inflammatory breast cancer to have a longer lifespan. The availability of genomic testing enables early detection of primary and acquired drug resistance as well as the assessment of treatment choices. In addition, an in-depth understanding of inflammatory breast cancer molecular biology will assist in the discovery of critical genomic alterations and oncogenic pathways that contribute to tumor formation and spreading. Future studies will give more valuable information that may be used in clinics to better treatment outcomes.

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Epstein–Barr Virus: How Its Lytic Phase Contributes to Oncogenesis

Microorganisms ◽

10.3390/microorganisms8111824 ◽

2020 ◽

Vol 8 (11) ◽

pp. 1824

Author(s):

Quincy Rosemarie ◽

Bill Sugden

Keyword(s):

Epstein Barr Virus ◽

Tumor Formation ◽

Gene Products ◽

Lytic Gene ◽

Barr Virus ◽

Oncogenic Pathways ◽

Epstein Barr ◽

Latent Phase

Epstein–Barr Virus (EBV) contributes to the development of lymphoid and epithelial malignancies. While EBV’s latent phase is more commonly associated with EBV-associated malignancies, there is increasing evidence that EBV’s lytic phase plays a role in EBV-mediated oncogenesis. The lytic phase contributes to oncogenesis primarily in two ways: (1) the production of infectious particles to infect more cells, and (2) the regulation of cellular oncogenic pathways, both cell autonomously and non-cell autonomously. The production of infectious particles requires the completion of the lytic phase. However, the regulation of cellular oncogenic pathways can be mediated by an incomplete (abortive) lytic phase, in which early lytic gene products contribute substantially, whereas late lytic products are largely dispensable. In this review, we discuss the evidence of EBV’s lytic phase contributing to oncogenesis and the role it plays in tumor formation and progression, as well as summarize known mechanisms by which EBV lytic products regulate oncogenic pathways. Understanding the contribution of EBV’s lytic phase to oncogenesis will help design ways to target it to treat EBV-associated malignancies.

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Metabolic engineering of CHO cells to prepare glycoproteins

Emerging Topics in Life Sciences ◽

10.1042/etls20180056 ◽

2018 ◽

Vol 2 (3) ◽

pp. 433-442 ◽

Cited By ~ 1

Author(s):

Qiong Wang ◽

Michael J. Betenbaugh

Keyword(s):

Metabolic Engineering ◽

Cho Cells ◽

Genetic Manipulation ◽

Chinese Hamster ◽

Post Translational Modification ◽

Effector Functions ◽

Recombinant Glycoproteins ◽

Production Platform ◽

Chemical Inhibitors ◽

Amino Acid Mutations

As a complex and common post-translational modification, N-linked glycosylation affects a recombinant glycoprotein's biological activity and efficacy. For example, the α1,6-fucosylation significantly affects antibody-dependent cellular cytotoxicity and α2,6-sialylation is critical for antibody anti-inflammatory activity. Terminal sialylation is important for a glycoprotein's circulatory half-life. Chinese hamster ovary (CHO) cells are currently the predominant recombinant protein production platform, and, in this review, the characteristics of CHO glycosylation are summarized. Moreover, recent and current metabolic engineering strategies for tailoring glycoprotein fucosylation and sialylation in CHO cells, intensely investigated in the past decades, are described. One approach for reducing α1,6-fucosylation is through inhibiting fucosyltransferase (FUT8) expression by knockdown and knockout methods. Another approach to modulate fucosylation is through inhibition of multiple genes in the fucosylation biosynthesis pathway or through chemical inhibitors. To modulate antibody sialylation of the fragment crystallizable region, expressions of sialyltransferase and galactotransferase individually or together with amino acid mutations can affect antibody glycoforms and further influence antibody effector functions. The inhibition of sialidase expression and chemical supplementations are also effective and complementary approaches to improve the sialylation levels on recombinant glycoproteins. The engineering of CHO cells or protein sequence to control glycoforms to produce more homogenous glycans is an emerging topic. For modulating the glycosylation metabolic pathways, the interplay of multiple glyco-gene knockouts and knockins and the combination of multiple approaches, including genetic manipulation, protein engineering and chemical supplementation, are detailed in order to achieve specific glycan profiles on recombinant glycoproteins for superior biological function and effectiveness.

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Loss of cellular motor protein contributes to tumor formation

PsycEXTRA Dataset ◽

10.1037/e458452008-005 ◽

2006 ◽

Keyword(s):

Motor Protein ◽

Tumor Formation ◽

Cellular Motor

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Reliability of Laboratory Tests for the Control of Oral Anticoagulation

Thrombosis and Haemostasis ◽

10.1055/s-0038-1647716 ◽

1974 ◽

Vol 32 (02/03) ◽

pp. 483-491

Author(s):

E. A Loeliger ◽

M. J Boekhout-Mussert ◽

L. P van Halem-Visser ◽

J. D. E Habbema ◽

H de Jonge

Keyword(s):

Human Brain ◽

Laboratory Tests ◽

Test Procedure ◽

Rabbit Brain ◽

Normal Range ◽

Test Procedures ◽

Discrimination Power ◽

Power Of The Test ◽

Assay Procedure ◽

Low Sensitivity

SummaryThe present study concerned the reproducibility of the so-called prothrombin time as assessed with a series of more commonly used modifications of the Quick’s onestage assay procedure, i.e. the British comparative reagent, homemade human brain thromboplastin, Simplastin, Simplastin A, and Thrombotest. All five procedures were tested manually on pooled lyophilized normal and patients’ plasmas. In addition, Simplastin A and Thrombotest were investigated semiautomatically on individual freshly prepared patients’ plasmas. From the results obtained, the following conclusions may be drawn :The reproducibility of results obtained with manual reading on lyophilized plasmas is satisfactory for all five test procedures. For Simplastin, the reproducibility of values in the range of insufficient anticoagulation is relatively low due to the low discrimination power of the test procedure in the near-normal range (so-called low sensitivity of rabbit brain thromboplastins). The reproducibility of Thrombotest excels as a consequence of its particularly easily discerned coagulation endpoint.The reproducibility of Thrombotest, when tested on freshly prepared plasmas using Schnitger’s semiautomatic coagulometer (a fibrinometer-liJce apparatus), is no longer superior to that of Simplastin A.The constant of proportionality between the coagulation times formed with Simplastin A and Thrombotest was estimated at 0.64.Reconstituted Thrombotest is stable for 24 hours when stored at 4° C, whereas reconstituted Simplastin A is not.The Simplastin A method and Thrombotest seem to be equally sensitive to “activation” of blood coagulation upon storage.

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