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Cancer stem cells (CSCs) are a cellular subpopulation accelerating cancer cell growth, invasion and metastasis and survival. After chemoradiotherapy, CSCs are enriched because of their survival advantages and lead to tumor relapse and metastasis. Elimination of CSCs is critically important for the radical treatment of human cancers. Long non-coding RNAs (lncRNAs) are a group of RNAs longer than 200 nucleotides and have no protein-coding potential. Aberrant expressions of lncRNAs are associated with human diseases including cancer. LncRNAs function as cancer biomarkers, prognostic factors and therapeutic targets. They induce cancer stemness by chromatin modification, transcriptional regulation or post-transcriptional regulation of target genes as a sponge or through assembling a scaffold complex. Several factors caused aberrant expressions of lncRNAs in CSCs such as genes mutations, epigenetic alteration and environmental stimuli. Targeting of lncRNAs has been demonstrated to significantly reverse the chemoradioresistance of CSCs. In this review, we have summarized the progress of studies regarding lncRNAs-mediated therapy resistance of CSCs and clarified the molecular mechanisms. Furthermore, we have for the first time analyzed the influences of lncRNAs on cell metabolism and emphasized the effect of tumor microenvironment on lncRNAs functions in CSCs. Overall, the thorough understanding of the association of lncRNAs and CSCs would contribute to the reversal of therapy resistance.

Novel hybrid diblock copolymers consisting of bidentate ligand-functionalized chains have been synthesized via click reaction and RAFT radical polymerization. The chemical structure and molecular weight of the synthesized poly(methacrylate-POSS)-block-poly(4-vinylbenzyl-2-pyridine-1H-1,2,3-triazole) (PMAPOSS-b-PVBPT) were characterized by NMR and GPC. The copolymers had been utilized to construct metal-containing polymer micelle by the metal–ligand coordination and electrostatic interaction in this study. The self-assembly behaviors of PMAPOSS-b-PVBPT in chloroform, a common solvent, under the effect of Zn(OTf)2 and HAuCl4 were investigated by TEM, DLS, and variable temperature NMR. Besides, micellization of this diblock copolymer was achieved in ethylene glycol, a selective solvent for PMAPOSS-b-PVBPT. The experimental results revealed that the incorporation of heterocyclic rings bearing nitrogen atoms in polymer side chains played an important role in the construction of metal-containing copolymer micelles. The prepared metal-containing PMAPOSS-b-PVBPT micelles had good dynamic and thermal stability due to the strong metal–ligand coordination interaction and electrostatic interaction.

Magnetic composite nanospheres (MCS) were first prepared via mini-emulsion polymerization. Subsequently, the hybrid core–shell nanospheres were used as carriers to support gold nanoparticles. The as-prepared gold-loading magnetic composite nanospheres (Au-MCS) had a hydrophobic core embed with γ-Fe3O4 and a hydrophilic shell loaded by gold nanoparticles. Both the content of γ-Fe3O4 and the size of gold nanoparticles could be controlled in our experiments, which resulted in fabricating various materials. On one hand, the Au-MCS could be used as a T2 contrast agent with a relaxivity coefficient of 362 mg−1 ml S−1 for magnetic resonance imaging. On the other hand, the Au-MCS exhibited tunable optical-absorption property over a wavelength range from 530 nm to 800 nm, which attributed to a secondary growth of gold nanoparticles. In addition, dynamic light scattering results of particle sizing and Zeta potential measurements revealed that Au-MCS had a good stability in an aqueous solution, which would be helpful for further applications. Finally, it showed that the Au-MCS were efficient catalysts for reductions of hydrophobic nitrobenzene and hydrophilic 4-nitrophenol that could be reused by a magnetic separation process. Copyright © 2014 John Wiley & Sons, Ltd.