From the rice fermentation product of a new record fungus, Neohelicosporium griseum, two new polyketides, neogrisphenol A (1) and neogrisphenol B (2), one new isochroman-1-one, (S)-6-hydroxy-7-methoxy-3,5-dimethylisochroman-1-one (3), and four known compounds (4–7) were isolated. Their structures were determined using 1D- and 2D-NMR, mass spectrometry, and chemical calculations. The C-3~C-2′ polymerization mode between the two α-naphthalenone derivative moieties is uncommon in compounds 1 and 2. Meanwhile, compounds 1–2 and 5 exhibited antibacterial activity against Bacillus subtilis, Clostridium perfringens, Staphylococcus aureus, and Staphylococcus aureus, with MIC values ranging between 16 and 31 µg/mL. In addition, compound 5 showed antifungal activity against Sclerotinia sclerotiorum and Phytophthora nicotianae var. nicotianae, with respective IC₅₀ values of 88.14 ± 2.21 µg/mL and 52.36 ± 1.38 µg/mL. Compound 1 showed significant cytotoxicity against A2780, PC-3, and MBA-MD-231 cell lines with respective IC₅₀ values of 3.20, 10.68, and 16.30 µM, and the cytotoxicity against A2780 cells was even higher than that of cisplatin (CDDP). With an IC₅₀ value of 10.13 µM, compound 2 also exhibited cytotoxicity against A2780. The in vitro results showed that compound 1 inhibited A2780 cell proliferation, induced apoptosis, and arrested the cell cycle at the S-phase in a concentration-dependent manner.

Neohelicomyces is a genus of helicosporous hyphomycetes with the potential to produce bioactive secondary metabolites. During a survey of helicosporous fungi in Guizhou and Hainan provinces, southern China, four isolates were obtained from both freshwater and terrestrial habitats. Based on combined analyses of multigene phylogenetic data (ITS, LSU, tef1-α, and rpb2) and morphological characteristics, two novel species, Neohelicomyces aquisubtropicus and N. wuzhishanensis, are proposed. Detailed descriptions, illustrations, and phylogenetic analyses of the new taxa are presented. Additionally, a checklist of currently accepted Neohelicomyces species supported by molecular data is provided.

Prostate cancer (PCa) is a common cancer and a major cause of cancer-related death worldwide in men, necessitating novel targets for cancer therapy. High expression of Bloom’s syndrome protein (BLM) helicase is associated with the occurrence and development of PCa. Therefore, the identification and development of new BLM inhibitors may be a new direction for the treatment of PCa. Here, we identified a novel inhibitor by molecular docking and put it to systematic evaluation via various experiments, AO/854, which acted as a competitive inhibitor that blocked the BLM-DNA interaction. Cellular evaluation indicated that AO/854-suppressed tumor growth and metastasis in PC3 cells by enhancing DNA damage, phosphorylating Chk1/Chk2, and altering the p53 signaling pathway. Collectively, the study highlights the potential of BLM as a therapeutic target in PCa and reveals a distinct mechanism by which AO/854 competitively inhibits the function of BLM.

Using standard DNA-damaging medicines with DNA repair inhibitors is a promising anticancer tool to achieve better therapeutic responses and reduce therapy-related side effects. Cell viability assay, neutral comet assay, western blotting (WB), and cell cycle and apoptosis analysis were used to determine the synergistic effect and mechanism of ML216, a Bloom syndrome protein (BLM) helicase inhibitor, and cisplatin (CDDP), a DNA-crosslinking agent, in PCa cells. Based on the online database research, our findings revealed that BLM was substantially expressed in PCa, which is associated with a bad prognosis for PCa patients. The combination of ML216 and CDDP improved the antiproliferative properties of three PCa cell lines. As indicated by the increased production of γH2AX and caspase-3 cleavage, ML216 significantly reduced the DNA damage-induced high expression of BLM, making PC3 more susceptible to apoptosis and DNA damage caused by CDDP. Furthermore, the combination of ML216 and CDDP increased p-Chk1 and p-Chk2 expression. The DNA damage may have triggered the ATR-Chk1 and ATM-Chk2 pathways simultaneously. Our results demonstrated that ML216 and CDDP combination therapy exhibited synergistic effects, and combination chemotherapy could be a novel anticancer tactic.

Tubeufia is a genus of helicosporous hyphomycetes distinguished by a high degree of morphological variation in its asexual morphs. During an investigation of helicosporous fungi in tropical regions, four fungal strains were isolated from submerged decaying wood in Hainan Province, southern China. Multigene phylogenetic analyses based on a combined ITS–LSU–tef1-α–rpb2 sequence dataset were conducted to determine the phylogenetic placement of the four fungal strains, which showed two distinct new species. Morphological characteristics were also used to support their taxonomic delimitation in addition to the molecular phylogeny. Two novel species, Tubeufia yanuodaensis and T. yinggelingensis, are described and illustrated.

Neohelicosporium species are a group of helicosporous hyphomycetes with the potential to produce novel bioactive natural compounds. During our investigation on helicosporous hyphomycetes, six isolates were collected from freshwater and terrestrial habitats in the tropical and subtropical regions of southern China. Based on multi-gene phylogenetic analyses (LSU-ITS-tef1-α-rpb2) and morphological comparisons of Neohelicosporium taxa, two new species (N. guizhouense and N. wuzhishanense) are introduced. Detailed micro-morphological descriptions, illustrations, and DNA molecular data are provided for the newly introduced species to confirm their taxonomic placements.