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Five new meroterpenoids, zizhines P-S and U (1−4,7), together with two known meroterpenoids (5 and 6) were isolated from Ganoderma sinensis. Their structures including absolute configurations were assigned by using spectroscopic, computational, and chemical methods. Racemics zizhines P and Q were purified by HPLC on chiral phase. Biological evaluation found that 4, 5 and 6 are cytotoxic toward human cancer cells (A549, BGC-823, Kyse30) with IC50 values in the range of 63.43−80.83 μM towards A549, 59.2 ± 2.73 μM and 64.25 ± 0.37 μM towards BGC-823, 76.28 ± 1.93 μM and 85.42 ± 2.82 μM towards Kyse30.

A novel sesquiterpene dimer, spirocommiphorfuran A (1); two new cadinane sesquiterpenoids, commiphorenes A (2) and B (3); along with three known terpenoids (4⁻6), were isolated from Resina Commiphora. The structures of these new compounds were characterized by NMR, HRESIMS, quantum chemical computation, and X-ray diffraction analysis. Compound 1 features a 7-oxabicyclo[2.2.1]heptane-2-ene core, representing the first example of germacrane-type sesquiterpene dimer fused via a spiro ring system. Compound 2 is a novel sesquiterpene with a completely new carbon skeleton, which is characteristic of an additional carbon attaching to the cadinane backbone via a carbon⁻carbon bond. Additionally, compounds 2 and 4 exert acceptable cytotoxicity toward normal cells and high selectivity in cancer cells, especially in HepG2 cells.

Background: Acute myeloid leukemia (AML) is initiated and maintained by a subset of self-renewing leukemia stem cells (LSCs), which contribute to the progression, recurrence and therapeutic resistance of leukemia. However, the mechanisms underlying the maintenance of LSCs drug resistance have not been fully defined. In this study, we attempted to elucidate the mechanisms of LSCs drug resistance. Methods: We performed reverse phase protein arrays to analyze the expression of anti-apoptotic proteins in the LSC-enriched leukemia cell line KG-1a. Immuno-blotting, cell viability and clinical AML samples were evaluated to verify the micro-assay results. The characteristics and transcriptional regulation of survivin were analyzed with the relative luciferase reporter assay, mutant constructs, chromatin immuno-precipitation (ChIP), quantitative real-time reverse transcription polymerase chain reaction (RT-qPCR), and western blotting. The levels of Sp1, c-Myc, phospho-extracellular signal-regulated kinase (p-ERK), phospho-mitogen and stress-activated protein kinase (p-MSK) were investigated in paired CD34+ and CD34- AML patient samples. Results: Survivin was highly over-expressed in CD34 + CD38- KG-1a cells and paired CD34+ AML patients compared with their differentiated counterparts. Functionally, survivin contributes to the drug resistance of LSCs, and Sp1 and c-Myc concurrently regulate levels of survivin transcription. Clinically, Sp1 and c-Myc were significantly up-regulated and positively correlated with survivin in CD34+ AML patients. Moreover, Sp1 and c-Myc were further activated by the ERK/MSK mitogen-activated protein kinase (MAPK) signaling pathway, modulating survivin levels. Conclusion: Our findings demonstrated that ERK/MSK/Sp1/c-Myc axis functioned as a critical regulator of survivin expression in LSCs, offering a potential new therapeutic strategy for LSCs therapy. [ABSTRACT FROM AUTHOR]