Application Potential of Bacterial Volatile Organic Compounds in the Control of Root-Knot Nematodes.

Plant-parasitic nematodes (PPNs) constitute the most damaging group of plant pathogens. Plant infections by root-knot nematodes (RKNs) alone could cause approximately 5% of global crop loss. Conventionally, chemical-based methods are used to control PPNs at the expense of the environment and human health. Accordingly, the development of eco-friendly and safer methods has been urged to supplement or replace chemical-based methods for the control of RKNs. Using microorganisms or their metabolites as biological control agents (BCAs) is a promising approach to controlling RKNs. Among the metabolites, volatile organic compounds (VOCs) have gained increasing attention because of their potential in the control of not only RKNs but also other plant pathogens, such as insects, fungi, and bacteria. This review discusses the biology of RKNs as well as the status of various control strategies. The discovery of VOCs emitted by bacteria from various environmental sources and their application potential as BCAs in controlling RKNs are specifically addressed.

Fumigant Activity of Bacterial Volatile Organic Compounds against the Nematodes Caenorhabditis elegans and Meloidogyne incognita.

Plant-parasitic nematodes infect a diversity of crops, resulting in severe economic losses in agriculture. Microbial volatile organic compounds (VOCs) are potential agents to control plant-parasitic nematodes and other pests. In this study, VOCs emitted by a dozen bacterial strains were analyzed using solid-phase microextraction followed by gas chromatography-mass spectrometry. Fumigant toxicity of selected VOCs, including dimethyl disulfide (DMDS), 2-butanone, 2-pentanone, 2-nonanone, 2-undecanone, anisole, 2,5-dimethylfuran, glyoxylic acid, and S-methyl thioacetate (MTA) was then tested against Caenorhabditis elegans. DMDS and MTA exhibited much stronger fumigant toxicity than the others. Probit analysis suggested that the values of LC50 were 8.57 and 1.43 µg/cm3 air for DMDS and MTA, respectively. MTA also showed stronger fumigant toxicity than DMDS against the root-knot nematode Meloidogyne incognita, suggesting the application potential of MTA.

MicroRNAs in human tongue squamous cell carcinoma: From pathogenesis to therapeutic implications.

Being one of the most aggressive cancers of oral cavity, tongue squamous cell carcinoma (TSCC) constitutes 41% of all oral carcinomas. Despite considerable improvements in multimodal diagnosis and treatment techniques, TSCC still remains to be one of the most lethal cancer types in the head and neck region. MicroRNAs are endogenously synthesized, small, non-coding RNAs, which are responsible for post-transcriptional regulation of mRNA expression. They are involved in regulation of almost all biological processes through their spatial and temporal expression. Their deregulation participates in pathogenesis of various diseases, including human TSCC, where they can act as potent oncogenes or tumor suppressors. Extensive microRNA profiling in TSCC samples and further in vitro and in vivo functional characterization of differentially expressed microRNAs revealed their contribution to the underlying molecular mechanisms of TSCC initiation, development, progression, metastasis, chemo-radioresistance, and recurrence. They are suggested as diagnostic and prognostic biomarkers for TSCC due to their differential expression in tumor tissues and their stability in body fluids like plasma, oral cytology, and saliva. MicroRNAs are, therefore, considered amongst the most promising candidates for development of novel therapeutic approaches against TSCC. In this review, we summarized important findings including our own works on microRNAs as implicated in TSCC and the new insights into the roles of microRNAs in squamous cell carcinoma of tongue.