Time-Lapse Video Microscopy and Single Cell Tracking to Study Neural Cell Behavior In Vitro

In this study, a simple time-lapse video recording system was used to compare developmental kinetics of female and male bovine embryos produced in vitro. Following embryo sex determination, the timing of each cleavage up to the 4-cell stage was compared between the sexes from the videotapes after culture in the presence and absence of glucose. In the second experiment, the consequences of exposure to a time-lapse video recording (TL) environment were studied by culturing embryos further until day 7 in an incubator, followed by collection and sex determination of morulae and blastocysts. In the absence of glucose, female embryos cleaved earlier than male ones. In the presence of glucose, however, male embryos cleaved earlier than female ones. There was no difference in the number of morulae/blastocysts in the absence of glucose, but in the presence of glucose more male than female embryos reached the morula and blastocyst stage. Exposure to the TL environment itself also had a sex-related effect, being more detrimental to male than female embryos. The difference in the number of functional X chromosomes between the sexes during early preimplantation development could explain these findings. In females, an increased capacity for oxygen radical detoxification through the pentose phosphate pathway could result in a reduced cleavage rate. Furthermore, glucose may influence the expression of enzymes located on the X chromosome. According to these results, a simple time-lapse video recording system is suitable for investigating embryo developmental kinetics and perhaps for the selection of embryos with the greatest developmental potential.

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Effect of targeting of syndecan-1 by microRNA miR-10b on breast cancer cell motility and invasiveness via a rho-GTPase- and E-cadherin-dependent mechanism.

Journal of Clinical Oncology ◽

10.1200/jco.2012.30.15_suppl.e21041 ◽

2012 ◽

Vol 30 (15_suppl) ◽

pp. e21041-e21041

Author(s):

Ludwig Kiesel ◽

Sherif Abdelaziz Ibrahim ◽

George W Yip ◽

Martin Gotte

Keyword(s):

Breast Cancer ◽

Cancer Cell ◽

Rho Gtpase ◽

Rho Kinase ◽

In Vitro Study ◽

Time Lapse ◽

Video Microscopy ◽

Migration And Invasion ◽

E Cadherin

e21041 Background: microRNAs are small endogenous non-coding RNAs, which posttranscriptionally regulate gene expression. In breast cancer, overexpression of the transmembrane heparan sulfate proteoglycan syndecan-1, a predicted target of the oncomiR miR-10b, correlates with poor clinical outcome. Here, we investigatet the potential functional relationship of miR-10b and syndecan-1 in an in vitro study. Methods: MDA-MB-231 and MCF-7 breast cancer cells were transiently transfected with pre-miR-10b, syndecan-1 siRNA or control reagents, respectively. Altered cell behaviour was monitored by proliferation, migration and invasion chamber assays, and time-lapse video microscopy. Results: miR-10b overexpression induced posttranscriptional downregulation of syndecan-1, as demonstrated by qPCR, flow cytometry, and 3’UTR luciferase assays, resulting in increased cancer cell migration and matrigel invasiveness. Syndecan-1 silencing generated a copy of this phenotype. Adhesion to fibronectin and laminin and basal cell proliferation were increased. Syndecan-1 co-immunoprecipitated with focal adhesion kinase, which showed increased activation upon syndecan-1 depletion. Affymetrix screening and confirmatory qPCR and Western blotting analysis of syndecan-1 deficient cells revealed upregulation of ATF-2, COX- 2, cadherin-11, vinculin, ACTG2, MYL9, transgelin-1, RhoA/C, MMP2 and heparanase, and downregulation of AML1/RUNX1, E-cadherin, CLDN1, p21WAF/CIP, Cdk6, TLR-4, PAI1/2, Collagen1alpha1, JHDM1D, Mpp4, MMP9, matrilin-2 and ANXA3/A10. Video microscopy demonstrated massively increased Rho kinase-dependent motility of syndecan-1-depleted cells, which displayed increased filopodia formation. Conclusions: We conclude that syndecan-1 is a novel target of the oncomiR miR-10b. Rho-GTPase dependent modulation of cytoskeletal function and downregulation of E-cadherin expression are identified as relevant effectors of the miR-10b-syndecan-1 axis, which emerges as a promising target for the development of new therapeutic approaches for breast cancer.

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Effective targeted antitumor activity of the antimicrobial agent taurolidine against relapsed/refractory neuroblastoma: Cytotoxicity, target modulation and tumor xenograft studies.

Journal of Clinical Oncology ◽

10.1200/jco.2019.37.15_suppl.e21502 ◽

2019 ◽

Vol 37 (15_suppl) ◽

pp. e21502-e21502

Author(s):

Lucy Swift ◽

Chunfen Zhang ◽

Antony Pfaffle ◽

Paul Chew ◽

Olga Kovalchuk ◽

...

Keyword(s):

Gene Expression ◽

Clinical Trial ◽

Early Phase ◽

Phase Contrast ◽

Time Lapse ◽

Early Phase Clinical Trial ◽

Phase Clinical Trial ◽

Time Lapse Video

e21502 Background: Neuroblastoma (NB) is the most common extracranial solid tumor and one of the most complex and difficult to treat diseases in pediatrics. Currently, even with highly aggressive treatment protocols, the prognosis for patients with high-risk and relapsed NB remains poor. Hence, there is a clear need to identify new agents and novel therapeutic strategies for the treatment of these children. Taurolidine (TRD) is derived from the aminosulfoacid taurine and has known anti-microbial and anti-inflammatory properties. TRD has demonstrated anti-neoplastic activity against a range of aggressive human tumors. We present mechanistic evidence and supportive preclinical data from in vitro and animal models of refractory NB for the development of an early phase clinical trial incorporating TRD. Methods: For in vitro activity studies, a panel of cell lines derived from patients with relapsed NB (n = 6) and normal control cells were treated with increasing concentrations of TRD and cell viability was measured by alamar blue assay. Phase-contrast light microscopy, western blotting, time-lapse video microscopy and analysis of global gene expression by RNA-Seq were used to evaluate target modulation and induction of cell death pathways. Bioluminescence imaging of mice bearing NB xenografts treated with TRD was used to investigate the efficacy of TRD in vivo. Results: Cell survival data showed that TRD is cytotoxic against NB cell lines in vitro (mean IC50 value 100 µM, range 65-135 µM). Phase-contrast and time-lapse video microscopy confirmed the antitumor effects of TRD. Western blot analyses identified that TRD induced target modulation and an effective apoptotic cascade, resulting in PARP cleavage. Gene expression analyses and signaling pathway activation scores indicated alterations in the Notch, MAPK and IL-10 signaling pathways. Xenograft studies further validated the in vivo activity of TRD with decreased tumor burden in treated mice and a measurable improvement in survival. Conclusions: Our study provides key pre-clinical data on the activity and mechanism of action of TRD against NB. The findings support the rationale for further evaluation of TRD for the treatment of relapsed/refractory NB patients in an early phase clinical trial.

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