Most investigations into cancer cell drug response are performed with cells cultured on flat (2D) tissue culture plastic. Emerging research has shown that the presence of a three-dimensional (3D) ...extracellular matrix (ECM) is critical for normal cell behavior including migration, adhesion, signaling, proliferation and apoptosis. In this study we investigate differences between cancer cell signaling in 2D culture and a 3D ECM, employing real-time, live cell tracking to directly observe U2OS human osteosarcoma and MCF7 human breast cancer cells embedded in type 1 collagen gels. The activation of the important PI3K signaling pathway under these different growth conditions is studied, and the response to inhibition of both PI3K and mTOR with PI103 investigated. Cells grown in 3D gels show reduced proliferation and migration as well as reduced PI3K pathway activation when compared to cells grown in 2D. Our results quantitatively demonstrate that a collagen ECM can protect U2OS cells from PI103. Overall, our data suggests that 3D gels may provide a better medium for investigation of anti-cancer drugs than 2D monolayers, therefore allowing better understanding of cellular response and behavior in native like environments.
Next-generation sequencing (NGS) of circulating tumor DNA (ctDNA) supports blood-based genomic profiling but is not yet routinely implemented in the setting of a phase I trials clinic. TARGET is a ...molecular profiling program with the primary aim to match patients with a broad range of advanced cancers to early phase clinical trials on the basis of analysis of both somatic mutations and copy number alterations (CNA) across a 641 cancer-associated-gene panel in a single ctDNA assay. For the first 100 TARGET patients, ctDNA data showed good concordance with matched tumor and results were turned round within a clinically acceptable timeframe for Molecular Tumor Board (MTB) review. When a 2.5% variant allele frequency (VAF) threshold was applied, actionable mutations were identified in 41 of 100 patients, and 11 of these patients received a matched therapy. These data support the application of ctDNA in this early phase trial setting where broad genomic profiling of contemporaneous tumor material enhances patient stratification to novel therapies and provides a practical template for bringing routinely applied blood-based analyses to the clinic.
The establishment of a reliable prenatal source of autologous, transgene-free progenitor cells has enormous potential in the development of regenerative-medicine-based therapies for infants born with ...devastating birth defects. Here, we show that a largely CD117-negative population of human amniotic fluid mesenchymal stromal cells (AF-MSCs) obtained from fetuses with or without prenatally diagnosed anomalies are readily abundant and have limited baseline differentiation potential when compared with bone-marrow-derived MSCs and other somatic cell types. Nonetheless, the AF-MSCs could be easily reprogrammed into induced pluripotent stem cells (iPSCs) using nonintegrating Sendai viral vectors encoding for OCT4, SOX2, KLF4, and cMYC. The iPSCs were virtually indistinguishable from human embryonic stem cells in multiple assays and could be used to generate a relatively homogeneous population of neural progenitors, expressing PAX6, SOX2, SOX3, Musashi-1, and PSA-NCAM, for potential use in neurologic diseases. Further, these neural progenitors showed engraftment potential in vivo and were capable of differentiating into mature neurons and astrocytes in vitro. This study demonstrates the usefulness of AF-MSCs as an excellent source for the generation of human transgene-free iPSCs ideally suited for autologous perinatal regenerative medicine applications.
Display omitted
•Trichoderma harzianum sensu lato TSM39 is a promising biocontrol agent of B. sorokiniana.•Trichoderma harzianum sensu lato TSM39 inhibits B. sorokiniana by mycoparasitism.•The ...chitinolytic system of strain TSM39 is induced by cellular components of B. sorokiniana.•Trichoderma harzianum sensu lato TSM39 can be produced by solid-state fermentation.
Bipolaris sorokiniana - the causal agent of wheat spot blotch - is an emerging phytopathogenic fungus in the Yaqui Valley, Sonora, Mexico. At present, its control relies on the use of harmful chemicals, partly due to the lack of effective alternatives. Thus, this work aimed to identify and characterize indigenous wheat-associated fungal strains with biocontrol capacity against B. sorokiniana that can be integrated into control strategies for spot blotch management. Out of 59 fungal strains evaluated, we identified 5 strains with antagonistic activity against B. sorokiniana by dual confrontation assay, and these were taxonomically assigned as Trichoderma harzianum sensu lato (strains TSM39 and TSO39), Aspergillus terreus (strains TRQ89 and TRQ93), and Aspergillus nidulans (strain TRQ83) based on phylogenetic analysis using the ITS region of the rRNA cistron. Trichoderma harzianum TSM39 showed interesting biological control traits (i.e., strong antagonistic activity, high growth rate, non-cytotoxicity) and its application to wheat plants - under highly conducive conditions for spot blotch outbreak- resulted in a significant reduction of disease severity. In vitro experiments revealed that the chitinolytic system of strain TSM39 responds to B. sorokiniana lysates (signals), which could have potential biotechnological applications to improve its biocontrol activity. Additionally, a solid-state fermentation system was successfully established for spore production of strain TSM39. Taken together, Trichoderma harzianum sensu lato TSM39 is a biocontrol agent against B. sorokiniana with the potential to be integrated into spot blotch management strategies and contribute to the sustainability of the region.
PDF
