Genome-wide profiling induced by ionizing radiation (IR) in non-small cell lung cancer (NSCLC) grown as three-dimensional spheroid

The Role of Biomimetic Hypoxia on Cancer Cell Behaviour in 3D Models: A Systematic Review

Simple Summary

Cancer remains one of the leading causes of death worldwide. The advancements in 3D tumour models provide in vitro test-beds to study cancer growth, metastasis and response to therapy. We conducted this systematic review on existing experimental studies in order to identify and summarize key biomimetic tumour microenvironmental features which affect aspects of cancer biology. The review noted the significance of in vitro hypoxia and 3D tumour models on epithelial to mesenchymal transition, drug resistance, invasion and migration of cancer cells. We highlight the importance of various experimental parameters used in these studies and their subsequent effects on cancer cell behaviour.

Abstract

The development of biomimetic, human tissue models is recognized as being an important step for transitioning in vitro research findings to the native in vivo response. Oftentimes, 2D models lack the necessary complexity to truly recapitulate cellular responses. The introduction of physiological features into 3D models informs us of how each component feature alters specific cellular response. We conducted a systematic review of research papers where the focus was the introduction of key biomimetic features into in vitro models of cancer, including 3D culture and hypoxia. We analysed outcomes from these and compiled our findings into distinct groupings to ascertain which biomimetic parameters correlated with specific responses. We found a number of biomimetic features which primed cancer cells to respond in a manner which matched in vivo response.

Deinococcus humi sp. nov., isolated from soil

A Gram-staining-positive, strictly aerobic, spherical, non-motile, red-pigmented bacterium, designated strain MK03T, was isolated from a soil sample collected in South Korea. The taxonomic position of the novel strain was investigated using a polyphasic approach. In phylogenetic analyses based on 16S rRNA gene sequences, strain MK03T was placed in a clade formed by members of the genus Deinococcus in the family Deinococcaceae and appeared to be most closely related to Deinococcus aerolatus 5516T-9T (97.4 % sequence similarity), Deinococcus marmoris AA-63T (97.2 %), Deinococcus radiopugnans ATCC 19172T (97.2 %) and Deinococcus saxicola AA-1444T (96.9 %). The genomic DNA G+C content of the novel strain was 64.5 mol%. The chemotaxonomic characteristics of strain MK03T were typical of members of the genus Deinococcus : MK-8 was identified as the predominant respiratory quinine, the major fatty acids were C16 : 1ω7c, C15 : 1ω6c, C16 : 0 and C15 : 0, ornithine was found to be the diamino acid in the cell-wall peptidoglycan and the novel strain showed resistance to gamma radiation, with a D10 value (i.e. the dose required to reduce the bacterial population by 10-fold) in excess of 9 kGy. In hybridization experiments, only low DNA–DNA relatedness values (11.6–34.5 %) were recorded between the novel strain and its closest relatives in the genus Deinococcus . Based on the phylogenetic, chemotaxonomic, phenotypic and DNA–DNA relatedness data, strain MK03T represents a novel species of the genus Deinococcus , for which the name Deinococcus humi sp. nov. is proposed. The type strain is MK03T ( = KCTC 13619T  = JCM 17915T).

Deinococcus daejeonensis sp. nov., isolated from sludge in a sewage disposal plant

A Gram-stain-positive, strictly aerobic, spherical, non-motile red-pigmented bacterial strain, designated MJ27T, was isolated from a sludge sample of the Daejeon sewage disposal plant in South Korea. A polyphasic approach was used to study the taxonomic position of strain MJ27T. Strain MJ27T shared highest 16S rRNA gene sequence similarity with Deinococcus grandis DSM 3963T (98.8 %), Deinococcus caeni Ho-08T (97.5 %) and Deinococcus aquaticus PB314T (96.6 %.); levels of sequence similarity with the type strains of other Deinococcus species were less than 96.0 %. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain MJ27T belonged to the clade formed by members of the genus Deinococcus in the family Deinococcaceae . The G+C content of the genomic DNA of strain MJ27T was 67.6 mol%. The chemotaxonomic characteristics of strain MJ27T were typical of members of the genus Deinococcus , with MK-8 as the predominant respiratory quinone, C16 : 1ω7c, C15 : 1ω6c, C16 : 0 and C15 : 0 as major fatty acids (>12 %), ornithine as the diamino acid in the cell-wall peptidoglycan and resistance to gamma radiation [D10 (dose required to reduce the bacterial population by tenfold) >9 kGy]. The low levels of DNA–DNA relatedness reported here (5.3±1.5–29.2±2.3 %) indicate that strain MJ27T represents a species that is separate from its closest relatives in the genus Deinococcus . On the basis of phylogenetic inference, fatty acid profile and other phenotypic properties, strain MJ27T is considered to represent a novel species of the genus Deinococcus , for which the name Deinococcus daejeonensis sp. nov. is proposed. The type strain is MJ27T ( = KCTC 13751T = JCM 16918T).