scholarly journals Reciprocal epigenetic Sox2 regulation by SMAD1-SMAD3 is critical for anoikis resistance and metastasis in cancer

2022 ◽  
Author(s):  
ZAINAB SHONIBARE ◽  
Mehri Monavarian ◽  
Kathleen O'Connell ◽  
Diego Altomare ◽  
Abigail K Shelton ◽  
...  
Keyword(s):  
Ovarian Cancer ◽  
Growth Factors ◽  
Cell Survival ◽  
Activin A ◽  
Tumor Burden ◽  
Type I ◽  
Anoikis Resistance ◽  
Sox2 Expression ◽  
Cell Death Pathways ◽  
Tumor Environment

Growth factors in the tumor environment are key regulators of cell survival and anoikis resistance during metastasis. Here we reveal significant dichotomy between TGF-β superfamily growth factors BMP and TGF-β/activin and their downstream SMAD effectors in regulation of anchorage-independent tumor cell survival in ovarian cancer. Gene expression profiling uncovered the transcription factor Sox2 as a key signaling node regulated in an opposing manner by anoikis-promoting BMP2 4 and 9 and anoikis-suppressing TGF-β and activin A. Mechanistically, repression of Sox2 by BMPs is mediated by type I receptors ALK2 and ALK3 induced SMAD1 activation, leading to SMAD1-dependent histone H3K27me3 recruitment and DNA methylation at SOX2s promoter. Conversely, TGF-β and activin A promote Sox2 expression directly by ALK5-mediated SMAD3 activation and histone H3K4me3 recruitment. Increased Sox2 expression promotes anoikis resistance, while decreasing Sox2 levels conversely reduces anoikis resistance and activates cell death pathways. Additionally, administrating BMP9 as a strategy to reduce Sox2 robustly inhibits intraperitoneal tumor burden and increases survival in multiple ovarian cancer xenograft models. Importantly, BMP-driven SMAD1 signaling can override the effects of TGF-β and activin on Sox2 regulation, which has potential clinical significance as we find high TGF-β levels in patient ascites. Our findings highlight the contrasting regulation of anoikis by distinct SMAD signaling pathways that are dependent on a novel dichotomous regulation of Sox2 and implicate the use of a subset of BMPs as a therapeutic strategy in cancer

scholarly journals Epigenetic therapy activates type I interferon signaling in murine ovarian cancer to reduce immunosuppression and tumor burden

2017 ◽  
Vol 114 (51) ◽  
pp. E10981-E10990 ◽  
Author(s):  
Meredith L. Stone ◽  
Katherine B. Chiappinelli ◽  
Huili Li ◽  
Lauren M. Murphy ◽  
Meghan E. Travers ◽  
...  
Keyword(s):  
Ovarian Cancer ◽  
Tumor Microenvironment ◽  
Immune Cells ◽  
Immune Checkpoint ◽  
Histone Deacetylase Inhibitors ◽  
Unmet Need ◽  
Tumor Burden ◽  
Epigenetic Therapy ◽  
Type I ◽  
Type I Ifn

Ovarian cancer is the most lethal of all gynecological cancers, and there is an urgent unmet need to develop new therapies. Epithelial ovarian cancer (EOC) is characterized by an immune suppressive microenvironment, and response of ovarian cancers to immune therapies has thus far been disappointing. We now find, in a mouse model of EOC, that clinically relevant doses of DNA methyltransferase and histone deacetylase inhibitors (DNMTi and HDACi, respectively) reduce the immune suppressive microenvironment through type I IFN signaling and improve response to immune checkpoint therapy. These data indicate that the type I IFN response is required for effective in vivo antitumorigenic actions of the DNMTi 5-azacytidine (AZA). Through type I IFN signaling, AZA increases the numbers of CD45+ immune cells and the percentage of active CD8+ T and natural killer (NK) cells in the tumor microenvironment, while reducing tumor burden and extending survival. AZA also increases viral defense gene expression in both tumor and immune cells, and reduces the percentage of macrophages and myeloid-derived suppressor cells in the tumor microenvironment. The addition of an HDACi to AZA enhances the modulation of the immune microenvironment, specifically increasing T and NK cell activation and reducing macrophages over AZA treatment alone, while further increasing the survival of the mice. Finally, a triple combination of DNMTi/HDACi plus the immune checkpoint inhibitor α-PD-1 provides the best antitumor effect and longest overall survival, and may be an attractive candidate for future clinical trials in ovarian cancer.

Co-targeting EGFR and Autophagy Impairs Ovarian Cancer Cell Survival during Detachment from the ECM

2015 ◽  
Vol 15 (3) ◽  
pp. 215-226 ◽  
Author(s):  
Zongyuan Yang ◽  
Yi Liu ◽  
Xiao Wei ◽  
Xiaoshui Zhou ◽  
Cheng Gong ◽  
...  
Keyword(s):  
Ovarian Cancer ◽  
Cell Survival ◽  
Cancer Cell ◽  
Ovarian Cancer Cell ◽  
Cancer Cell Survival

scholarly journals Evaluating Targeted Therapies in Ovarian Cancer Metabolism: Novel Role for PCSK9 and Second Generation mTOR Inhibitors

Cancers ◽  
2021 ◽  
Vol 13 (15) ◽  
pp. 3727
Author(s):  
Dafne Jacome Sanz ◽  
Juuli Raivola ◽  
Hanna Karvonen ◽  
Mariliina Arjama ◽  
Harlan Barker ◽  
...  
Keyword(s):  
Ovarian Cancer ◽  
Lipid Metabolism ◽  
Cell Survival ◽  
Drug Testing ◽  
Cancer Metabolism ◽  
Ex Vivo ◽  
Specific Inhibitor ◽  
Low Grade ◽  
Serous Ovarian Cancer

Background: Dysregulated lipid metabolism is emerging as a hallmark in several malignancies, including ovarian cancer (OC). Specifically, metastatic OC is highly dependent on lipid-rich omentum. We aimed to investigate the therapeutic value of targeting lipid metabolism in OC. For this purpose, we studied the role of PCSK9, a cholesterol-regulating enzyme, in OC cell survival and its downstream signaling. We also investigated the cytotoxic efficacy of a small library of metabolic (n = 11) and mTOR (n = 10) inhibitors using OC cell lines (n = 8) and ex vivo patient-derived cell cultures (PDCs, n = 5) to identify clinically suitable drug vulnerabilities. Targeting PCSK9 expression with siRNA or PCSK9 specific inhibitor (PF-06446846) impaired OC cell survival. In addition, overexpression of PCSK9 induced robust AKT phosphorylation along with increased expression of ERK1/2 and MEK1/2, suggesting a pro-survival role of PCSK9 in OC cells. Moreover, our drug testing revealed marked differences in cytotoxic responses to drugs targeting metabolic pathways of high-grade serous ovarian cancer (HGSOC) and low-grade serous ovarian cancer (LGSOC) PDCs. Our results show that targeting PCSK9 expression could impair OC cell survival, which warrants further investigation to address the dependency of this cancer on lipogenesis and omental metastasis. Moreover, the differences in metabolic gene expression and drug responses of OC PDCs indicate the existence of a metabolic heterogeneity within OC subtypes, which should be further explored for therapeutic improvements.

scholarly journals Utilizing the ABC Transporter for Growth Factor Production by fleQ Deletion Mutant of Pseudomonas fluorescens

Biomedicines ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 679
Author(s):  
Benedict-Uy Fabia ◽  
Joshua Bingwa ◽  
Jiyeon Park ◽  
Nguyen-Mihn Hieu ◽  
Jung-Hoon Ahn
Keyword(s):  
Growth Factors ◽  
Growth Factor ◽  
Pseudomonas Fluorescens ◽  
Abc Transporter ◽  
Transforming Growth Factor Beta ◽  
Deletion Mutant ◽  
Transforming Growth Factor ◽  
Gene Knockout ◽  
Type I ◽  
Double Deletion

Pseudomonas fluorescens, a gram-negative bacterium, has been proven to be a capable protein manufacturing factory (PMF). Utilizing its ATP-binding cassette (ABC) transporter, a type I secretion system, P. fluorescens has successfully produced recombinant proteins. However, besides the target proteins, P. fluorescens also secretes unnecessary background proteins that complicate protein purification and other downstream processes. One of the background proteins produced in large amounts is FliC, a flagellin protein. In this study, the master regulator of flagella gene expression, fleQ, was deleted from P. fluorescens Δtp, a lipase and protease double-deletion mutant, via targeted gene knockout. FleQ directs flagella synthesis, so the new strain, P. fluorescens ΔfleQ, does not produce flagella-related proteins. This not only simplifies purification but also makes P. fluorescens ΔfleQ an eco-friendly expression host because it will not survive outside a controlled environment. Six recombinant growth factors, namely, insulin-like growth factors I and II, beta-nerve growth factor, fibroblast growth factor 1, transforming growth factor beta, and tumor necrosis factor beta, prepared using our supercharging method, were successfully secreted by P. fluorescens ΔfleQ. Our findings demonstrate the potential of P. fluorescens ΔfleQ, combined with our supercharging process, as a PMF.

scholarly journals Randomised phase II trial of olaparib, chemotherapy or olaparib and cediranib in patients with platinum-resistant ovarian cancer (OCTOVA): a study protocol

BMJ Open ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. e041463
Author(s):  
Anita Mansouri ◽  
Naomi McGregor ◽  
Rachel Dunn ◽  
Sam Dobbie ◽  
Jane Holmes ◽  
...  
Keyword(s):  
Ovarian Cancer ◽  
Clinical Trials ◽  
Antiangiogenic Therapy ◽  
Single Agent ◽  
Unmet Need ◽  
Dropout Rate ◽  
Weekly Paclitaxel ◽  
Type I ◽  
Link Type ◽  
Platinum Based Chemotherapy

IntroductionPatients relapsing within 12 months of platinum-based chemotherapy usually have a poorer response to subsequent treatments. To date, extensive research into the mechanism of resistance to platinum agents in the treatment of ovarian cancer has not resulted in improved responses or longer survival. Further experimental work and clinical trials with novel agents are therefore justified to address this unmet need.Patients with ovarian, fallopian tube or primary peritoneal cancer that has relapsed within 12 months of platinum-based chemotherapy will be randomised with stratification for BReast CAncer gene (BRCA) status, prior poly (ADP-ribose) polymerase (PARP) exposure and prior antiangiogenic therapy into weekly paclitaxel (chemotherapy), olaparib or the combination of cediranib and olaparib. They will be followed until disease progression or unacceptable toxicity develops. Our trial design permits two investigations. We will compare the efficacy and tolerability of single-agent olaparib with weekly paclitaxel. We will also compare the efficacy and tolerability of olaparib with the combination of olaparib and cediranib. The required sample size of 138 participants (46 per arm) was calculated using a 20% one-sided type I error, 80% power and 15% dropout rate. Recruitment will last 34 months with a follow-up of 18 months.Methods and analysisEthics and disseminationThis study will be conducted under a UK Medicines and Healthcare Products Regulatory Agency Clinical Trials Authorisation. Approval to conduct the study was obtained from the responsible authority before beginning the study. The sponsor will retain ownership of all data arising from the trial. We aim to publish this research in a specialist peer-reviewed scientific journal on study completion. EudraCT number: 2016-000559-28, ethics reference number: 16/LO/2150.Trial registration numberISRCTN: ISRCTN14784018, clinicaltrials.gov: NCT03117933; Pre-results.

scholarly journals The Epithelial–Mesenchymal Transcription Factor SNAI1 Represses Transcription of the Tumor Suppressor miRNA let-7 in Cancer

Cancers ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 1469
Author(s):  
Hanmin Wang ◽  
Evgeny Chirshev ◽  
Nozomi Hojo ◽  
Tise Suzuki ◽  
Antonella Bertucci ◽  
...  
Keyword(s):  
Ovarian Cancer ◽  
Stem Cell ◽  
Cancer Cells ◽  
Epithelial Mesenchymal Transition ◽  
Tumor Burden ◽  
Cell Phenotype ◽  
Mesenchymal Transition ◽  
Carcinoma Cell Lines ◽  
Future Work

We aimed to determine the mechanism of epithelial–mesenchymal transition (EMT)-induced stemness in cancer cells. Cancer relapse and metastasis are caused by rare stem-like cells within tumors. Studies of stem cell reprogramming have linked let-7 repression and acquisition of stemness with the EMT factor, SNAI1. The mechanisms for the loss of let-7 in cancer cells are incompletely understood. In four carcinoma cell lines from breast cancer, pancreatic cancer, and ovarian cancer and in ovarian cancer patient-derived cells, we analyzed stem cell phenotype and tumor growth via mRNA, miRNA, and protein expression, spheroid formation, and growth in patient-derived xenografts. We show that treatment with EMT-promoting growth factors or SNAI1 overexpression increased stemness and reduced let-7 expression, while SNAI1 knockdown reduced stemness and restored let-7 expression. Rescue experiments demonstrate that the pro-stemness effects of SNAI1 are mediated via let-7. In vivo, nanoparticle-delivered siRNA successfully knocked down SNAI1 in orthotopic patient-derived xenografts, accompanied by reduced stemness and increased let-7 expression, and reduced tumor burden. Chromatin immunoprecipitation demonstrated that SNAI1 binds the promoters of various let-7 family members, and luciferase assays revealed that SNAI1 represses let-7 transcription. In conclusion, the SNAI1/let-7 axis is an important component of stemness pathways in cancer cells, and this study provides a rationale for future work examining this axis as a potential target for cancer stem cell-specific therapies.

scholarly journals A comprehensive study on 2D, 3D and solid tumor environment to explore a multifunctional biogenic nanoconjugate

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
B. S. Unnikrishnan ◽  
G. U. Preethi ◽  
T. T. Sreelekha
Keyword(s):  
Drug Delivery ◽  
Iron Oxide ◽  
Iron Oxide Nanoparticles ◽  
Tumor Burden ◽  
Oxide Nanoparticles ◽  
Cell Internalization ◽  
Tumor Environment ◽  
D Cell ◽  
Cancer Spheroids ◽  
Comprehensive Study

AbstractEmergence of nanotechnology created a drastic change in the field of cancer therapy due to their unique features in drug delivery and imaging. Polysaccharide based nanoparticles have received extensive attention in recent years as promising nanoparticle mediated drug delivery systems. Polysaccharides are endorsed with versatile merits including high drug encapsulation efficiency, efficient drug protection against chemical or enzymatic degradation, unique ability to create a controlled release and cellular internalization. In the current study, we have fabricated doxorubicin-loaded carboxymethylated PST001 coated iron oxide nanoparticles (DOX@CM-PST-IONPs) for better management of cancer. CM-PST coated iron oxide nanoparticles co-encapsulated with chemotherapeutic drug doxorubicin, can be utilized for targeted drug delivery. Biocompatible and non-toxic nanoconjugates was found to be effective in both 2-D and 3-D cell culture system with efficient cancer cell internalization. The bench-marked potential of CM-PIONPs to produce reactive oxygen species makes it a noticeable drug delivery system to compact neoplasia. These nanoconjugates can lay concrete on a better way for the elimination of cancer spheroids and tumor burden.

P–803 Novel culture conditions for the improvement of the in vitro expansion of human male fetal germ cells

2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
M Martin ◽  
M Ferreira ◽  
J Taelman ◽  
C Eguizabal ◽  
S M Chuv. d. Sous. Lopes
Keyword(s):  
Growth Factors ◽  
Germ Cells ◽  
Activin A ◽  
Culture Conditions ◽  
Media Culture ◽  
Germline Stem Cell ◽  
Growth Media ◽  
Human Male ◽  
In Vitro Expansion

Abstract Study question Do different ECMs/substrates and growth media culture conditions improve in vitro male human primordial germ cell (hPGC) expansion? Summary answer We achieved in vitro expansion improvement of male hPGCs with specific growth factors such as LIF, EGF, FGF2 and GDNF on gelatin- and vitronectin-coating cultures. What is known already PGCs are the precursors of male and female gametes, which are specified during early mammalian post-implantation embryonic development. PGCs undergo sequential cell divisions to differentiate into pro-spermatogonia (pSPG). In vitro propagation of pSPG could be important to understand the transition to spermatogonial stem cells (SSCs), important for fertility preservation in patients with infertility. Here, we aimed at performing a comparative analysis on in vitro feeder-free culture systems, based on different extracellular matrix (ECM) and growth media culture conditions, to support the expansion of the male germline stem cell populations using second trimester human male gonads as primary material. Study design, size, duration We collected human 2nd trimester male fetal gonads from elective abortions. Male gonads were dissected in saline solution (0.9% NaCl) and were either fixed overnight in 4% paraformaldehyde (PFA) for immunohistochemistry or disaggregated by enzymatic digestion for in vitro culture. Participants/materials, setting, methods After differential plating, fetal cells were cultured for 6 days. Disaggregated gonads were cultured with two different growing media (Medium 1 supplemented with LIF, EGF, FGF–2 and GDNF and Medium 2 supplemented with RA, BMP 4 and Activin A) on gelatin, laminin, vitronectin or matrigel coated plates. Cultured cells were immunostained, quantified for the expression of DDX4 and POU5F1 after 3 days (D3) and 6 days (D6) of culture. Main results and the role of chance We pursued to evaluate whether germ cells dissociated from a pool of male fetal gonads could propagate in vitro when cultured for D6 in different conditions. We observed that expansion of POU5F1-positive early PGCs and DDX4-positive late PGCs was only observed when cells were plated on gelatin or vitronectin and cultured with Medium 1, containing the growth factors LIF, EGF, FGF2 and GDNF. However, a reduced percentage of PGCs was observed in all four different coatings when grown with Medium 2, containing RA, BMP4 and Activin A. We analyzed the relative expression of the PGC markers POU5F1, DDX4 and MAGEA4 in histological sections of gonads from embryos at 18.5 weeks of gestation. Two populations of hPGCs were observed: ∼10–30% of the gonadal cells expressed solely DDX4 (late PGCs), whereas less than 10% of gonadal cells expressed POU5F1 (early PGCs). SOX9 and STARD1 expression was evaluated, confirming the presence of Sertoli cells and Leydig cells, respectively. Limitations, reasons for caution Due to the limited and difficulty to obtain human fetal tissue, a limited number of samples were used. Wider implications of the findings: We expanded human male fetal germ cells in vitro for D6 on gelatin and vitronectin coated plates with Medium 1, containing growth factors LIF, EGF, FGF2 and GDNF. Our findings provide a 2D culture system to expand hPGCs that could be useful to study propagation to pSPGs and eventually SSCs. Trial registration number Not applicable

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