Project description:Mouse androgenetic haploid embryonic stem cells (mAG-haESCs) can be utilized to uncover gene functions, especially those of genes with recessive effects, and to produce semicloned mice when injected into mature oocytes. However, mouse haploid cells undergo rapid diploidization during long-term culture in vitro and subsequently lose the advantages of haploidy and the factors that drive diploidization are not well understood. In this study, we compared the small RNAs (sRNAs) of mAG-haESCs, normal ESCs and mouse round spermatids by high-throughput sequencing and identified distinct sRNA profiles. Several let-7 family members and miR-290-295 cluster miRNAs were found significantly differentially transcribed. Knockdown and overexpression experiments showed that let-7a and let-7g suppress diploidization while miR-290a facilitates diploidization. Our study revealed the unique sRNA profile of mAG-haESCs and demonstrated that let-7a overexpression can mitigate diploidization in mAG-haESCs. These findings will help us to better understand mAG-haESCs and utilize them as a tool in the future.
Project description:Background: Ferroptosis, an iron-dependent form of regulated cell death driven by lipid peroxidation (LPO), represents a promising therapeutic strategy. Magnolia officinalis, a traditional herb for resolving dampness and phlegm, is known to modulate cellular metabolism. While magnolol (MAG), a bioactive neolignan from Magnolia officinalis, shows anti-TNBC activity, its role in inducing ferroptosis remains unexplored. Methods: Anti-TNBC effects of MAG were assessed in MDA-MB-231 and 4T1 cells via viability, apoptosis, and ferroptosis assays (intracellular Fe²⁺, LPO, GSH). Target identification employed network pharmacology, RNA-seq, surface plasmon resonance, and pull-down assays. Mechanisms were validated using siRNA/overexpression, Co-IP, and immunofluorescence. In vivo efficacy was evaluated in xenograft models. Results: MAG inhibited proliferation and induced apoptosis and ferroptosis in TNBC cells, evidenced by elevated Fe²⁺ and lipid peroxidation, depleted GSH, downregulated SLC7A11/GPX4, and mitochondrial shrinkage effects reversed by ferroptosis inhibitors. MAG directly bound and suppressed transcription factor ETS2. ETS2 knockdown sensitized cells to MAG-induced ferroptosis, while its overexpression restored SLC7A11/GPX4 expression and conferred resistance. Mechanistically, ETS2 transcriptionally regulated SLC7A11, and MAG enhanced ETS2-SLC7A11 protein interaction. In vivo, MAG significantly suppressed tumor growth with low toxicity and downregulated ETS2, SLC7A11, and GPX4. Conclusions: MAG induces ferroptosis in MDA-MB-231 cells, which may be mediated by targeting the ETS2/SLC7A11/GPX4 signaling axis, providing mechanistic insights into its anti-TNBC activity.
Project description:Particle-attached bacterioplankton and eukaryote composition of surface seawater during the spring bloom at Helgoland in the year 2018
Project description:Colorectal cancer (CRC) is one of the most common and mortal types of cancer. There is increasing evidence that some polyunsaturated fatty acids (PUFA) exercise specific inhibitory actions on cancer cells through different mechanisms, as a previous study on the effect on CRC cells of two PUFA free fatty acids (FFA), docosahexaenoic acid (DHA, 22:6n3) and arachidonic acid (ARA, 20:4n6)-FFA, shown. Here we have used the same study design and technology to investigate the actions of DHA and ARA-monoacylglycerols (MAG), and we have compared the results with the previous study of the corresponding FFA. Cell assays revealed that ARA- and DHA-MAG exercised dose- and time-dependent antiproliferative actions, with DHA-MAG acting on cancer cells more efficiently than ARA-MAG. SWATH-MS massive quantitative proteomics, validated by parallel reaction monitoring and followed by pathway analysis, revealed that DHA-MAG had a massive effect in the proteasome complex, while ARA-MAG main effect was related to DNA replication. Prostaglandin synthesis also resulted inhibited by DHA-MAG. Results clearly demonstrated the ability of MAGs to induce cell death in colon cancer cells and suggested a direct relationship between chemical structure and effect.