Hinokitiol-induced decreases of tyrosinase and microphthalmia-associated transcription factor are mediated by the endoplasmic reticulum-associated degradation pathway in human melanoma cells

Design, synthesis and anti-oomycete activity of 2-acyloxyhinokitiol derivatives

In order to explore novel natural product-based anti-oomycete agent, ten 2-acyloxyhinokitiol derivatives (5a-j) were designed and synthesised, and structurally confirmed by 1H NMR,13C NMR, HRMS, and melting point. The stereochemical configuration of compound 5f was unambiguously confirmed by single-crystal X-ray diffraction. Furthermore, we evaluated the target compounds 5a-j as anti-oomycete activity against a serious agricultural disease of Phytophthora capsici. Among the ten hinokitiol ester derivatives tested, four compounds 5d, 5g, 5h and 5j had anti-oomycete activity higher than the positive control zoxamide (EC50 = 23.59 mg/L), and the EC50 values of 18.90, 20.62, 13.61 and 21.29 mg/L, respectively. Especially compound 5h exhibited the best anti-oomycete activity against P. capsici with EC50 value of 13.61 mg/L. Overall, the anti-oomycete activities of 2-acyloxyhinokitiol derivatives is higher than that of 2-sulfonyloxyhinokitiol derivatives. The results laid a good foundation for the subsequent synthesis of hinokitiol ester derivatives with significant anti-oomycete activity.

AAFL: automatic association feature learning for gene signature identification of cancer subtypes in single-cell RNA-seq data

Single-cell RNA-sequencing (scRNA-seq) technologies have enabled the study of human cancers in individual cells, which explores the cellular heterogeneity and the genotypic status of tumors. Gene signature identification plays an important role in the precise classification of cancer subtypes. However, most existing gene selection methods only select the same informative genes for each subtype. In this study, we propose a novel gene selection method, automatic association feature learning (AAFL), which automatically identifies different gene signatures for different cell subpopulations (cancer subtypes) at the same time. The proposed AAFL method combines the residual network with the low-rank network, which selects genes that are most associated with the corresponding cell subpopulations. Moreover, the differential expression genes are acquired before gene selection to filter the redundant genes. We apply the proposed feature learning method to the real cancer scRNA-seq data sets (melanoma) to identify cancer subtypes and detect gene signatures of identified cancer subtypes. The experimental results demonstrate that the proposed method can automatically identify different gene signatures for identified cancer subtypes. Gene ontology enrichment analysis shows that the identified gene signatures of different subtypes reveal the key biological processes and pathways. These gene signatures are expected to bring important implications for understanding cellular heterogeneity and the complex ecosystem of tumors.

Synthesis of hinokitiol sulfonate derivatives and their anti-oomycete and nematicidal activities

In order to explore novel natural product-based anti-oomycete and nematicidal agents, sixteen unreported 2-sulfonyloxyhinokitiol derivatives were prepared using the principle of active splicing, and structurally confirmed by proton nuclear magnetic resonance (1H NMR), carbon-13 nuclear magnetic resonance (13C NMR), high-resolution mass spectrometry (HRMS), and melting point. Moreover, we evaluated the title compounds as anti-oomycete and nematicidal agents against two serious agricultural pests of Phytophthora capsici and Meloidogyne incongnita. Among the sixteen hinokitiol esters tested: (1) Compounds 3a and 3m exhibited the most potent anti-oomycete activity compared to zoxamide against P. capsici, and the median effective concentration (EC50) values of 3a, 3m, and zoxamide were 18.64, 21.11, and 23.15 mg/L, respectively; Further studies showed that the existence of seven membered ring and carbonyl group was the necessary condition for the high anti-oomycete activity of hinokitiol. (2) Compounds 3n and 3p exhibited more promising nematicidal activity than hinokitiol, and the median lethal concentration (LC50) values of 3n, 3p and 1 against M. incongnita were 0.2111, 0.2079, and 0.3933 mg/L, respectively. This result will pave the way for further modification of hinokitiol to develop potential new fungicides and nematicides.