Selective targeting of an oncogenic KRAS mutant allele by CRISPR/Cas9 induces efficient tumor regression

AbstractBackgroundKRAS is one of the most frequently mutated oncogenes in human cancers, but its activating mutations have remained undruggable due to its picomolar affinity for GTP/GDP and its smooth protein structure resulting in the absence of known allosteric regulatory sites.ResultsWith the goal of treating mutated KRAS-driven cancers, two CRISPR systems, CRISPR-SpCas9 genome-editing system and transcription-regulating system dCas9-KRAB, were developed to directly deplete KRAS mutant allele or to repress its transcription in cancer cells, respectively, through guide RNA specifically targeting the mutant but not wild-type allele. The effect of in vitro proliferation and cell cycle on cancer cells as well as in vivo tumor growth was examined after delivery of Cas9 system. SpCas9 and dCas9-KRAB systems with sgRNA targeting the mutant allele both blocked the expression of mutant KRAS gene, leading to an inhibition of cancer cell proliferation. Local adenoviral injections using SpCas9 and dCas9-KRAB systems both suppressed tumor growth in vivo. The gene-depletion system (SpCas9) performed more effectively than the transcription-suppressing system (dCas9-KRAB) on tumor inhibition. Application of both Cas9 systems to wild-type KRAS tumor cells did not affect cell proliferation in vitro and in vivo. Furthermore, through bioinformatic analysis of 31555 SNP mutations of the top 20 cancer driver genes, we showed that our mutant-specific editing strategy could be extended to a list of oncogenic mutations with high editing potentials, and this pipeline can be applied to analyze the distribution of PAM sequence in the genome to survey the best targets for other editing purpose.ConclusionsWe successfully developed both gene-depletion and transcription-suppressing systems to specifically target an oncogenic mutant allele of KRAS which led to significant tumor regression. It provides a promising strategy for the treatment of tumors with driver gene mutations.

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Aptamer-Protamine-siRNA Nanoparticles in Targeted Therapy of ErbB3 Positive Breast Cancer Cells

10.21203/rs.3.rs-42522/v1 ◽

2020 ◽

Author(s):

Xiangshang Xu ◽

Li Li ◽

Xiaolan Li ◽

Deding Tao ◽

Peng Zhang ◽

...

Keyword(s):

Breast Cancer ◽

Cell Cycle ◽

Tumor Growth ◽

Cancer Cells ◽

Tumor Regression ◽

Inhibit Tumor Growth ◽

Mcf 7 ◽

Positive Breast Cancer

Abstract Background: RNAi-based technology has achieved good results in both in vitro and in vivo applications, and it is expected to become a good genetic treatment for some diseases, especially neoplastic diseases. But there are still many obstacles in the in vivo application, the most important thing is the lack of an efficient and safe carrier.Methods: In this study, we designed and constructed a new siRNA delivery, which was named as aptamer-protamine-siRNA nanoparticle (APR). APR was consisted of ErbB3 aptamer, protamine and siRNA. We used Zeta nanosize to detect the size of APR to verify whether it is a nano-scale compound. We use the FAMRNA to replace the siRNA to detect whether APR could recognize and enter ErbB3 positive MCF-7 cells. The we replaced the siRNA as oncogene suvivin siRNA to detect whether APR could inhibit tumor growth by silence surviving, and replaced siRNA to CDK1 siRNA to detect the cell cycle blocking effect. At last we tested the anticancer effect and safety of APR by carrying survivin siRNA in MCF-7 bearing nude mice. Results: APR was identified as a nanoscale compound. It showed specific targeting for ErbB3-positive MCF-7 cancer cells. APR has demonstrated the characteristics of inhibiting tumor growth by carrying siRNA against oncogene survivin. APR could also block cell cycle of MCF-7 cells by delivering CDK1 siRNAs. In the ErbB3 positive breast cancer xenograft mice model, APR nanoparticles could inhibit tumor growth and cause tumor regression without any toxicity. Conclusions: In both in vivo and in vitro applications, APR nanoparticles could be targeted to recognize and enter ErbB3 positive tumor cells, and play a corresponding role by silencing targeted gene expression. APR nanoparticle is expected to become a good tumor treatment option.

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E-cadherin promotes cell hyper-proliferation in breast cancer

10.1101/2020.11.04.368746 ◽

2020 ◽

Author(s):

Gabriella C. Russo ◽

Michelle N. Karl ◽

David Clark ◽

Julie Cui ◽

Ryan Carney ◽

...

Keyword(s):

Cell Proliferation ◽

Tumor Growth ◽

Cancer Cells ◽

Adhesion Molecule ◽

Intercellular Adhesion ◽

Normal Cells ◽

Mesenchymal Transition ◽

E Cadherin

ABSTRACTThe loss of the intercellular adhesion molecule E-cadherin is a hallmark of the epithelial-mesenchymal transition (EMT), which promotes a transition of cancer cells to a migratory and invasive phenotype. E-cadherin is associated with a decrease in cell proliferation in normal cells. Here, using physiologically relevant 3D in vitro models, we find that E-cadherin induces hyper-proliferation in breast cancer cells through activation of the Raf/MEK/ERK signaling pathway. These results were validated and consistent across multiple in vivo models of primary tumor growth and metastatic outgrowth. E-cadherin expression dramatically increases tumor growth and, without affecting the ability of cells to extravasate and colonize the lung, significantly increases macrometastasis formation via cell proliferation at the distant site. Pharmacological inhibition of MEK1/2, blocking phosphorylation of ERK in E-cadherin-expressing cells, significantly depresses both tumor growth and macrometastasis. This work suggests a novel role of E-cadherin in tumor progression and identifies a potential new target to treat hyper-proliferative breast tumors.SUMMARYE-cadherin, an extensively studied transmembrane molecule ubiquitously expressed in normal epithelial tissues, promotes and maintains intercellular adhesion. In cancer, the loss of adhesion molecule E-cadherin is associated with onset of invasion via epithelial-to-mesenchymal transition (EMT) process.1 EMT consists of a highly orchestrated cascade of molecular events where epithelial cells switch from a non-motile phenotype to an invasive, migratory phenotype accompanied by a change in cell morphology.1,2 These processes are believed to then trigger metastasis in carcinomas (cancers of epithelial origin). Moreover, the expression of intercellular adhesion molecule E-cadherin (E-cad) is associated with a decrease in cell proliferation in normal cells. Classical experiments in fibroblasts and epithelial cells show that the expression of E-cad not only promotes cell-cell adhesion, but also reduces cell proliferation and onset of apoptosis.3,4 Altogether these results have long supported that E-cad acts as a tumor suppressor gene.1,2However, despite its role in cell-adhesion the requirement for loss of E-cad in metastasis has recently been re-assessed.5,6,7,8These investigations focus on E-cad’s role in EMT, even though the relationship between E-cad and proliferation is just as intriguing. While E-cad has been shown to have anit-proliferative effects in normal cells, E-cad also helps maintain a pluripotent and proliferative phenotype in stem cells, and notably is lost during differentiation, a non-proliferative step of stem cell progression.9,10 Yet, despite potentially important implications in our understanding of tumor progression, whether E-cad expression affects growth in cancer cells remains mostly unexplored.Here, utilizing a physiologically relevant 3D in vitro model and multiple in vivo models, we studied the impact of E-cad on cell proliferation at the primary tumor site and proliferation at a secondary site. Remarkably, E-cad upregulates multiple proliferation pathways, including hyper-activation of the ERK cascade within the greater MAPKinase pathway, resulting in a dramatic increase in cell proliferation in vitro and tumor growth in vivo. When the phosphorylation of ERK is blocked utilizing a MEK1/2 inhibitor, PD032590111, this effect is reversed in vitro and in vivo. Thus, E-cad plays an oncogenic role in tumorigenesis and merits evaluation as a potential new drug target.

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DPP3 Expression Promotes Cell Proliferation and Migration in Vitro and Tumor Growth in Vivo That Associates with Poor Prognosis of Esophageal Carcinoma

10.21203/rs.3.rs-1078211/v1 ◽

2021 ◽

Author(s):

Jing-Kun Liu ◽

Abulizi Abudula ◽

Hai-Tao Yang ◽

Li-Xiu Xu ◽

Ge Bai ◽

...

Keyword(s):

Cell Proliferation ◽

Esophageal Cancer ◽

Tumor Growth ◽

Esophageal Carcinoma ◽

Cancer Cells ◽

Xenograft Model ◽

Esophageal Cancer Cells ◽

Tumor Growth And Invasion

Abstract Background: Dipeptidyl peptidase III (DPP3) is a zinc-dependent metallopeptidase and elevated in a variety of malignant tumors, but the underlying mechanism is not well understood so far. Here we investigated the association of esophageal carcinogenesis with the regulation of DPP3 expression by tissue-based quantitative analysis and the depletion of DPP3 expression in esophageal cancer cells and xenograft model. Methods: The expression level of DPP3 in esophageal cancer tissues and adjacent normal tissues was detected in 93 cases of tissue biopsies collected from patients diagnosed with esophageal carcinoma by immunohistochemistry. The effect of DPP3 expression on cell proliferation, migration or apoptosis was determined in DPP3-depleted esophageal cancer cells created by infection with the lentivirus containing the shRNA specific to human DPP3 mRNA sequence followed by cytometric detection using celigo cell count assay, flow cytometry, wound-healing assay and trans-well assay as well as chip screening with a Human Apoptosis Antibody Array kit, which enables the quantitative detection of 43 apoptosis-related genes. A xenograft model was applied to the detection of tumor growth and invasion of DPP3-depleted cancer cells in nude mice.Results: DPP3 expression was elevated in esophageal cancer tissues compared with adjacent non-tumor tissues (normal controls) with statistical significance (P<0.05), and associated with poor prognosis of esophageal carcinoma. The DPP3-depletion resulted in a reduced cell proliferation and migration and enhanced cell-cycle arrest and apoptosis of esophageal cancer cells, and lead to the inhibition of tumor growth and invasion in xenograft model. In addition, DPP3-depletion was associated with the upregulation of pro-apoptotic proteins and the downregulation of anti-apoptotic proteins.Conclusions: These findings suggest that DPP3 may promote cell proliferation, migration and survival of esophageal cancer cells in vitro, and tumor growth and invasion of esophageal carcinoma in vivo and this might serve as a molecular target for tumor therapy.

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Long noncoding RNA LINC01296 plays an oncogenic role in colorectal cancer by suppressing p15 expression

Journal of International Medical Research ◽

10.1177/03000605211004414 ◽

2021 ◽

Vol 49 (5) ◽

pp. 030006052110044

Author(s):

Jianing Xu ◽

Zhehao Zhang ◽

Dong Shen ◽

Ting Zhang ◽

Jinsong Zhang ◽

...

Keyword(s):

Colon Cancer ◽

Cell Proliferation ◽

Tumor Growth ◽

Cancer Cells ◽

Long Noncoding Rna ◽

Noncoding Rna ◽

Colon Cancer Cells ◽

Normal Tissues

Objective To examine the role of the long noncoding RNA LINC01296 in colorectal carcinoma (CRC) and to explore the underlying mechanism. Methods We detected LINC01296 expression levels in a cohort of 51 paired CRC and normal tissues. We also assessed the effects of LINC01296 on cell proliferation and apoptosis in CRC cells in vitro, and measured its effect on tumor growth in an in vivo mouse model. We identified the potential downstream targets of LINC01296 and assessed its regulatory effects. Results Expression levels of LINC01296 were elevated in 37/51 CRC tissues compared with the corresponding normal tissues and were significantly associated with tumor stage, lymph node metastasis, and distant metastasis. Knockdown of LINC01296 using antisense oligonucleotides inhibited cell proliferation and promoted apoptosis of colon cancer cells in vitro and inhibited tumor growth in vivo. Knockdown of LINC01296 also significantly increased the gene expression of p15 in colon cancer cells. LINC01296-specific suppression of p15 was validated by the interaction between enhancer of zeste homolog 2 and LINC01296. Conclusion Overexpression of LINC01296 suppressed the expression of p15 leading to CRC carcinogenesis. These findings may provide the basis for novel future CRC-targeted therapies.

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LncRNA UCA1 promotes development of gastric cancer via the miR-145/MYO6 axis

Cellular & Molecular Biology Letters ◽

10.1186/s11658-021-00275-8 ◽

2021 ◽

Vol 26 (1) ◽

Author(s):

An Yang ◽

Xin Liu ◽

Ping Liu ◽

Yunzhang Feng ◽

Hongbo Liu ◽

...

Keyword(s):

Gastric Cancer ◽

Cell Proliferation ◽

Cancer Cells ◽

Cell Apoptosis ◽

Gastric Cancer Cell ◽

Gastric Cancer Cells ◽

Gastric Cancer Cell Lines ◽

Development Of Gastric Cancer

Abstract Background Long noncoding RNA (lncRNA), urothelial carcinoma-associated 1 (UCA1) is aberrantly expressed in multiple cancers and has been verified as an oncogene. However, the underlying mechanism of UCA1 in the development of gastric cancer is not fully understood. In the present study, we aimed to identify how UCA1 promotes gastric cancer development. Methods The Cancer Genome Atlas (TCGA) and Genotype-Tissue Expression (GTEx) data were used to analyze UCA1 and myosin VI (MYO6) expression in gastric cancer. Western blot and quantitative real-time PCR (QPCR) were performed to test the expression level of the UCA1/miR-145/MYO6 axis in gastric cancer cell lines and tissues. The roles of the UCA1/miR-145/MYO6 axis in gastric cancer in vitro and in vivo were investigated by CCK-8 assay, flow cytometry, siRNAs, immunohistochemistry, and a mouse xenograft model. The targeted relationship among UCA1, miR-145, and MYO6 was predicted using LncBase Predicted v.2 and TargetScan online software, and then verified by luciferase activity assay and RNA immunoprecipitation. Results UCA1 expression was higher but miR-145 expression was lower in gastric cancer cell lines or tissues, compared to the adjacent normal cell line or normal tissues. Function analysis verified that UCA1 promoted cell proliferation and inhibited cell apoptosis in the gastric cancer cells in vitro and in vivo. Mechanistically, UCA1 could bind directly to miR-145, and MYO6 was found to be a downstream target gene of miR-145. miR-145 mimics or MYO6 siRNAs could partly reverse the effect of UCA1 on gastric cancer cells. Conclusions UCA1 accelerated cell proliferation and inhibited cell apoptosis through sponging miR-145 to upregulate MYO6 expression in gastric cancer, indicating that the UCA1/miR-145/MYO6 axis may serve as a potential therapeutic target for gastric cancer.

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KLF7/VPS35 axis contributes to hepatocellular carcinoma progression through CCDC85C-activated β-catenin pathway

Cell & Bioscience ◽

10.1186/s13578-021-00585-6 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Yarong Guo ◽

Bao Chai ◽

Junmei Jia ◽

Mudan Yang ◽

Yanjun Li ◽

...

Keyword(s):

Hepatocellular Carcinoma ◽

Cell Proliferation ◽

Tumor Growth ◽

Luciferase Reporter ◽

Aberrant Expression ◽

Proliferation And Invasion ◽

Hcc Cells

Abstract Objective Dysregulation of KLF7 participates in the development of various cancers, but it is unclear whether there is a link between HCC and aberrant expression of KLF7. The aim of this study was to investigate the role of KLF7 in proliferation and migration of hepatocellular carcinoma (HCC) cells. Methods CCK8, colony growth, transwell, cell cycle analysis and apoptosis detection were performed to explore the effect of KLF7, VPS35 and Ccdc85c on cell function in vitro. Xenografted tumor growth was used to assess in vivo role of KLF7. Chip-qPCR and luciferase reporter assays were applied to check whether KLF7 regulated VPS35 at transcriptional manner. Co-IP assay was performed to detect the interaction between VPS35 and Ccdc85c. Immunohistochemical staining and qRT-PCR analysis were performed in human HCC sampels to study the clinical significance of KLF7, VPS35 and β-catenin. Results Firstly, KLF7 was highly expressed in human HCC samples and correlated with patients’ differentiation and metastasis status. KLF7 overexpression contributed to cell proliferation and invasion of HCC cells in vitro and in vivo. KLF7 transcriptional activation of VPS35 was necessary for HCC tumor growth and metastasis. Further, co-IP studies revealed that VPS35 could interact with Ccdc85c in HCC cells. Rescue assay confirmed that overexpression of VPS35 and knockdown of Ccdc85c abolished the VPS35-medicated promotion effect on cell proliferation and invasion. Finally, KLF7/VPS35 axis regulated Ccdc85c, which involved in activation of β-catenin signaling pathway, confirmed using β-catenin inhibitor, GK974. Functional studies suggested that downregulation of Ccdc85c partly reversed the capacity of cell proliferation and invasion in HCC cells, which was regulated by VPS35 upregulation. Lastly, there was a positive correlation among KLF7, VPS35 and active-β-catenin in human HCC patients. Conclusion We demonstrated that KLF7/VPS35 axis promoted HCC cell progression by activating Ccdc85c-medicated β-catenin pathway. Targeting this signal axis might be a potential treatment strategy for HCC.

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POU2F2 promotes the proliferation and motility of lung cancer cells by activating AGO1

BMC Pulmonary Medicine ◽

10.1186/s12890-021-01476-9 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Ronggang Luo ◽

Yi Zhuo ◽

Quan Du ◽

Rendong Xiao

Keyword(s):

Lung Cancer ◽

Tumor Growth ◽

Cancer Cells ◽

Cancer Progression ◽

Human Lung ◽

Lung Cancer Cells ◽

Human Lung Cancer ◽

Cancer Tissues

Abstract Background To detect and investigate the expression of POU domain class 2 transcription factor 2 (POU2F2) in human lung cancer tissues, its role in lung cancer progression, and the potential mechanisms. Methods Immunohistochemical (IHC) assays were conducted to assess the expression of POU2F2 in human lung cancer tissues. Immunoblot assays were performed to assess the expression levels of POU2F2 in human lung cancer tissues and cell lines. CCK-8, colony formation, and transwell-migration/invasion assays were conducted to detect the effects of POU2F2 and AGO1 on the proliferaion and motility of A549 and H1299 cells in vitro. CHIP and luciferase assays were performed for the mechanism study. A tumor xenotransplantation model was used to detect the effects of POU2F2 on tumor growth in vivo. Results We found POU2F2 was highly expressed in human lung cancer tissues and cell lines, and associated with the lung cancer patients’ prognosis and clinical features. POU2F2 promoted the proliferation, and motility of lung cancer cells via targeting AGO1 in vitro. Additionally, POU2F2 promoted tumor growth of lung cancer cells via AGO1 in vivo. Conclusion We found POU2F2 was highly expressed in lung cancer cells and confirmed the involvement of POU2F2 in lung cancer progression, and thought POU2F2 could act as a potential therapeutic target for lung cancer.

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Knockdown CYP2S1 inhibits lung cancer cells proliferation and migration

Cancer Biomarkers ◽

10.3233/cbm-210189 ◽

2021 ◽

pp. 1-9

Author(s):

Huan Guo ◽

Baozhen Zeng ◽

Liqiong Wang ◽

Chunlei Ge ◽

Xianglin Zuo ◽

...

Keyword(s):

Lung Cancer ◽

Cell Proliferation ◽

Cell Growth ◽

Cancer Cells ◽

Molecular Mechanisms ◽

Lung Cancer Cells ◽

Invasion And Migration ◽

And Migration

BACKGROUND: The incidence of lung cancer in Yunnan area ranks firstly in the world and underlying molecular mechanisms of lung cancer in Yunnan region are still unclear. We screened a novel potential oncogene CYP2S1 used mRNA microassay and bioinformation database. The function of CYP2S1 in lung cancer has not been reported. OBJECTIVE: To investigate the functions of CYP2S1 in lung cancer. METHODS: Immunohistochemistry and Real-time PCR were used to verify the expression of CYP2S1. Colony formation and Transwell assays were used to determine cell proliferation, invasion and migration. Xenograft assays were used to detected cell growth in vivo. RESULTS: CYP2S1 is significantly up-regulated in lung cancer tissues and cells. Knockdown CYP2S1 in lung cancer cells resulted in decrease cell proliferation, invasion and migration in vitro. Animal experiments showed downregulation of CYP2S1 inhibited lung cancer cell growth in vivo. GSEA analysis suggested that CYP2S1 played functions by regulating E2F targets and G2M checkpoint pathway which involved in cell cycle. Kaplan-Meier analysis indicated that patients with high CYP2S1 had markedly shorter event overall survival (OS) time. CONCLUSIONS: Our data demonstrate that CYP2S1 exerts tumor suppressor function in lung cancer. The high expression of CYP2S1 is an unfavorable prognostic marker for patient survival.

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Inhibition of MCF-7 breast cancer cell proliferation by 5alpha-dihydrotestosterone; a role for p21(Cip1/Waf1)

Journal of Molecular Endocrinology ◽

10.1677/jme.0.0320793 ◽

2004 ◽

Vol 32 (3) ◽

pp. 793-810 ◽

Cited By ~ 47

Author(s):

MA Greeve ◽

RK Allan ◽

JM Harvey ◽

JM Bentel

Keyword(s):

Breast Cancer ◽

Cell Proliferation ◽

Cancer Cells ◽

Breast Cancer Cells ◽

S Phase ◽

Cyclin D3 ◽

P27 Kip1 ◽

Mcf 7

Androgens inhibit the growth of breast cancer cells in vitro and in vivo by mechanisms that remain poorly defined. In this study, treatment of asynchronously growing MCF-7 breast cancer cells with the androgen, 5alpha-dihydrotestosterone (DHT), was shown to inhibit cell proliferation and induce moderate increases in the proportion of G1 phase cells. Consistent with targeting the G1-S phase transition, DHT pretreatment of MCF-7 cultures impeded the serum-induced progression of G1-arrested cells into S phase and reduced the kinase activities of cyclin-dependent kinase (Cdk)4 and Cdk2 to less than 50% of controls within 3 days. DHT treatment was associated with greater than twofold increases in the levels of the Cdk inhibitor, p27(Kip1), while p21(Cip1/Waf1) protein levels remained unchanged. During the first 24 h of DHT treatment, levels of Cdk4-associated p21(Cip1/Waf1) and p27(Kip1) were reduced coinciding with decreased levels of Cdk4-associated cyclin D3. In contrast, DHT treatment caused increased accumulation of Cdk2-associated p21(Cip1/Waf1), with no significant alterations in levels of p27(Kip1) bound to Cdk2 complexes. These findings suggest that DHT reverses the Cdk4-mediated titration of p21(Cip1/Waf1) and p27(Kip1) away from Cdk2 complexes, and that the increased association of p21(Cip1/Waf1) with Cdk2 complexes in part mediates the androgen-induced growth inhibition of breast cancer cells.

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