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Cancer metastasis is the leading cause of mortality in cancer patients. Over 70% of lung cancer patients are diagnosed at advanced or metastatic stages, and this results in an increased incidence of mortality. Terrein is a secondary bioactive fungal metabolite isolated from Aspergillus terreus . Numerous studies have demonstrated that terrein has anticancer properties, but in the present study, the cellular mechanisms underlying the inhibition of lung cancer cell metastasis by terrein was investigated for the first time. Using MTT assays, the cytotoxic effects of terrein were first examined in human lung cancer cells (A549 cells) and then compared with its cytotoxic effects in three noncancer control cell lines (Vero kidney, L6 skeletal muscle and H9C2 cardiomyoblast cells). The results indicated that terrein significantly reduced the viability of all these cells but exhibited a different level of toxicity in each cell type; these results revealed a specific concentration range in which the effect of terrein was specific to A549 cells. This significant cytotoxic effect of terrein in A549 cells was verified using LDH assays. It was then demonstrated that terrein attenuated the proliferation of A549 cells using IncuCyte image analysis. Regarding its antimetastatic effects, terrein significantly inhibited A549 cell adhesion, migration and invasion. In addition, terrein suppressed the angiogenic processes of A549 cells, including vascular endothelial growth factor (VEGF) secretion, capillary-like tube formation and VEGF/VEGFR2 interaction. These phenomena were accompanied by reduced protein levels of integrins, FAK, and their downstream mediators (e.g., PI3K, AKT, mTORC1 and P70S6K). All these data indicated that terrein was able to inhibit all the major metastatic processes in human lung cancer cells, which is crucial for cancer treatment.

Terrein is a fungal metabolite that has already been reported with anticancer properties. However, the effect on the aggressive phenotype of cancer cells has not been elucidated yet.  In the present study, the cytotoxicity of terrein was first determined against lung cancer cells (A549) model and compared with several normal cell lines (Vero, L6, and H9C2 cells). The data demonstrated that terrein had a specific effect on A549 cells relative to normal cells with high selectivity index values. Then, the hypoxic model that recognized to induce aggressive abilities was established in A549 cells by cobalt chloride (CoCl2) stimulation. With this model, terrein could reduce HIF-1α, a marker of hypoxia, and inhibit both migration and invasion of which the effect on invasion is more explicit. Our results demonstrated that terrein has a potential new role as the anti-aggressive phenotype by inhibiting cancer cell migration and invasion through HIF-1α reduction. HIGHLIGHTS Terrein, a secondary bioactive metabolite extracted from Aspergillus terreus, demonstrates anticancer effect on lung cancer cells with less cytotoxic on normal cells CoCl2 treatment was successfully used for creating hypoxic model which resulting in HIF-1a augmentation and aggressive abilities enhancement in lung cancer cells Terrein could reduce HIF-1a expression and invasive ability of lung cancer cells demonstrated the potential role as anti-metastatic agent for lung cancer GRAPHICAL ABSTRACT

Among soil isolated species of actinomycetes bacteria that affected the growth of aflatoxin producing mold; Aspergillus flavus TISTR 3041, the isolate SP-O2 showed a promising inhibitory activity on the dual culture assay. This isolated bacterium was characterized on various International Streptomyces Project media. The macroscopic morphological analysis showed mycelium, sporogenesis, and orangish pink of colonial pigment. The scanning electron microscope (SEM) photograph showed that the sporogenesis has occurred by shrinking of both sides of aerial mycelium. After the sporogenesis has been completed, the fragmentation of altered mycelium started from the tips of aerial mycelium to produce 0.8-1 micrometer fragmented spores. The 16S rRNA sequences analysis revealed that isolate SP-O2 shared a 99.93 % (1 mismatch/1436 nt) similarity with Streptomyces spectabilis NBRC 13424 AB184393. Co-culture liquid assay was analyzed for the aflatoxin produced by A. flavus in the presence of Streptomyces spectabilis SP-O2. The result showed that UV-visualized band of aflatoxin B1 was not detected by co-cultivation of Streptomyces spectabilis SP-O2 with A. flavus by thin layer chromatography compared to the control. Indeed, fungal growth of A. flavus was destroyed by the antifungal substance produced by Streptomyces spectabilis SP-O2 in the liquid culture. Furthermore, biocontrol of contaminated A. flavus was conducted on peanut kernels and the results showed that Streptomyces spectabilis SP-O2 has antifungal activity against the presence of A. flavus. Together, these results suggested that further investigation on the development of biocontrol use of Streptomyces spectabilis SP-O2 to overcome the contamination of aflatoxin producing mold in the feedstock and agricultural-based industry is needed. HIGHLIGHTS The isolated actinobacteria in this study was identified as Streptomyces spectabilis isolate SP-O2 based on its morphological characteristics, physiological properties and molecular identification SEM showed the sporogenesis of 0.8-1 micrometer fragmented spores Streptomyces spectabilis isolate SP-O2 exhibited the promising fungicidal activity against flavus in the dual culture agar assay, co-culture liquid assay and peanut kernels assay with consistency results The secreted metabolites play a crucial role on the fungal killing against Aspergillus flavus rather than the aflatoxin degradation GRAPHICAL ABSTRACT

The macrolide brefeldin A (BFA, 1) exhibited high cytotoxicity against KB cells. However, it was also toxic against non-cancerous cells. In order to lower toxicity against normal cells while maintaining the cytotoxic potency to the cancer cells, structural modification of this compound was undertaken. Starting from compound 1, the analogues 2-13 were synthesized and evaluated for cytotoxicity against KB cells. The analogue 2 exhibited the most potent cytotoxicity against KB cells, with an IC50 value of 0.034 nM, 67-fold more active than its parent compound 1. It was 41764 and 8235 fold more active than the standard drugs ellipticine and doxorubicin, respectively. The higher cytotoxicity against KB cells and lower toxicity against Vero cells of analogue 2 than those of the parent compound 1 contributed to its exceptionally high selectivity index of 9117. The results suggested that this analogue might be utilized to develop a new candidate for an anticancer drug. HIGHLIGHTS Oral cancer is a major worldwide public health issue and may affect any oral cavity region, including the lips, tongue, mouth and throat The ester analogues (2-13) were the first report of the cytotoxic against human epidermoid carcinoma (KB) cells 7-O-acetyl BFA (2) exhibited the most potent cytotoxicity against KB cells, with an IC50 value of 034 nM, 67-fold more active than its parent compound 1 The essentially structural features for the macrolide of BFA-type to exhibit high cytotoxicity against KB cells are the presence of a free hydroxyl group at the 4-position, a free hydroxyl group or the corresponding ester at the 7-position, and unsaturated functions at the 2- and 10-positions GRAPHICAL ABSTRACT