A novel cell-wall polysaccharide derived from the stipe of Agaricus bisporus inhibits mouse melanoma proliferation and metastasis.

Malignant melanoma is an invasive and highly aggressive skin cancer that-if diagnosed-poses a serious threat to the patient's health and life. In this work, a novel purified cell-wall polysaccharide (termed Abwp) was obtained from the discarded stipe of Agaricus bisporus (A. bisporus) and characterized to be a novel homogeneous polysaccharide consisted of a ß-(1 â†’ 4)- glucosyl backbone with ß-(1 â†’ 2) and (1 â†’ 6)-d-glucosyl side-chains. The anti-melanoma effects of Abwp and its associated mechanisms in mice were then explored using in vitro and in vivo approaches. In vitro results showed that Abwp inhibited B16 melanoma cell proliferation and promoted their apoptosis in both time- and dose-dependent manners. In B16 cells induced with tumor necrosis factor (TNF-α), Abwp significantly decreased the protein expression of inflammatory-related signaling pathway (e.g., p38 MAPK and NF-κB) in time-, concentration-, and dose-dependent manners. Moreover, Abwp blocked nuclear entry of NF-κB-p65. In an in vivo mouse model featuring neoplasm transplantation with B16 melanoma cells, Abwp significantly inhibited the growth and proliferation of mouse melanoma. Hematoxylin staining showed that the invasion of melanoma cells into the lung tissue of the Abwp-treated group was significantly reduced. Immunohistochemical analysis showed that the expression of proliferation cell nuclear antigen (PCNA), N-cadherin, MMP-9, and Snail in the lung of mouse was significantly inhibited. Immunofluorescence showed that Abwp significantly interfered with the nuclear transcription of NF-κB-p65 in a dose-dependent manner. Collectively, these results showed that Abwp mediated p38 MAPK and NF-κB signaling pathways to inhibit the inflammatory response and malignant proliferation and metastasis of melanoma in mice.

LOC101929709 promotes gastric cancer progression by aiding LIN28B to stabilize c-MYC mRNA.

BACKGROUND: LIN28B plays a critical role in the Warburg effect. However, its underlying mechanism remains elusive. Recently, it has been reported that LIN28B could collaborate with IGF2BP3, which can bind to m6A-modified c-MYC transcripts. Therefore, this study investigated if LIN28B recognises methylated c-MYC mRNA to promote the Warburg effect in gastric cancer. METHODS: Effects of LIN28B on gastric cancer were confirmed in vitro and in vivo. On the basis of bioinformatics analysis, the association between LIN28B and c-MYC mRNA was shown using RNA immunoprecipitation (RIP) and luciferase reporter assays. The role of m6A was identified by RNA pull-down assays. We further performed RIP-seq to search for long non-coding RNAs (lncRNAs) participating in the LIN28B binding process. Chromatin immunoprecipitation was used to show the impact of c-MYC on transcription of LIN28B and lncRNAs. RESULTS: LIN28B was identified to stabilize c-MYC mRNA by recognizing m6A. Furthermore, the interaction between c-MYC mRNA and LIN28B is speculated to be supported by LOC101929709, which binds to both LIN28B and IGF2BP3. Functional experiments revealed that LOC101929709 promotes the proliferation, migration and glycolysis of gastric cancer. Mechanistically, LOC101929709 enriched in the cytoplasm helps LIN28B stabilize c-MYC mRNA. Moreover, c-MYC promoted the transcription of both LOC101929709 and LIN28B. Additionally, LOC101929709 also activated the PI3K/AKT pathway. CONCLUSIONS: The c-MYC/LOC101929709/LIN28B axis promotes aerobic glycolysis and tumour progression. Thus, LOC101929709 can be a novel potential target for gastric cancer treatment.

The active component screening of Anoectochilus roxburghii and the functional study on inhibition of melanogenesis in zebrafish.

The aim of this study is to explore the active components of Anoectochilus roxburghii capable of inhibiting melanin formation using chemical separation and extraction and functional analysis. Anoectochilus roxburghii were extracted with alcohol and separated into three groups: the total extraction group, alcohol extracted group and alcohol precipitated group. Zebrafish embryos at 0.75 h post-fertilization were exposed to various concentrations of the three groups of extracts, and analyzed at 72 h, using semi-quantitative RT-PCR and in situ hybridization. The results showed that the alcohol extracts inhibit melanogenesis most significantly in the zebrafish embryos. The mRNAs of melanin-related genes, such as silv, tyr, tyrp1a, were down-regulated by the alcohol extracts spatially and temporally. The alcohol extracts also inhibited the activity of tyrosinase, a key enzyme in melanogenesis, in a dosage dependent manner. In addition, the alcohol extracts also display a remarkable inhibitory effect on melanin synthesis through down-regulation of mRNAs of melanin-related genes and tyrosinase activity in zebrafish embryos, in which a large amount of melanin has already been synthesized. Such inhibitory effect could be reversed after the withdrawal of the alcohol extracts. Our results showed that the alcohol extracts of Anoectochilus roxburghii can significantly inhibit zebrafish melanogenesis, supporting the notion that Anoectochilus roxburghii could potentially be used in the development and production of natural whitening products.

Response surface optimization of conditions for culturing Azotobacter chroococcum in Agaricus bisporus industrial wastewater.

In the present study, the conditions for Azotobacter chroococcum fermentation using Agaricus bisporus wastewater as the culture medium were optimized. We analyzed the total number of living A. chroococcum in the fermentation broth, using multispectral imaging flow cytometry. Single-factor experiments were carried out, where a Plackett-Burman design was used to screen out three factors from the original six processing factors wastewater solubility, initial pH, inoculum size, liquid volume, culture temperature, and rotation speed that affected the total number of viable A. chroococcum. The Box-Behnken response surface method was used to optimize the interactions between the three main factors and to predict the optimal fermentation conditions. Factors significantly affecting the total number of viable A. chroococcum, including rotation speed, wastewater solubility, and culture temperature, were investigated. The optimum conditions for A. chroococcum fermentation in A. bisporus wastewater were a rotation speed of 200 rpm, a solubility of 0.25%, a culture temperature of 26°C, an initial pH of 6.8, a 5% inoculation volume, a culture time of 48 h, and a liquid volume of 120 mL in a 250 mL flask. Under these conditions, the concentration of total viable bacteria reached 4.29 ± 0.02 ✕ 107 Obj/mL A. bisporus wastewater can be used for the cultivation of A. chroococcum.

KLF16 promotes proliferation in gastric cancer cells via regulating p21 and CDK4.

Krüppel-like factors (KLFs), such as KLF4, KLF2, KLF5 and KLF15, have been extensively investigated in multi-cancers. However, KLF16, a member of KLFs, hasn't been well identified in cancer, especially in gastric cancer (GC). Here, we investigated the roles of KLF16 in GC. In present study, we found that KLF16 expression levels were significantly up-regulated in GC tissues compared to adjacent normal tissues both in protein and mRNA levels by using immunohistochemistry assays (IHC) and real-time quantitative PCR (qPCR). And KLF16 expression levels were positively correlated to tumor size, invasion depth, lymphatic metastasis and TNM stage. Furthermore, KLF16 expression also could predict prognosis in patients with GC. Moreover, the knock-down of KLF16 could significantly suppress proliferation via increasing p21 expression and decreasing CDK4 expression in GC cell lines. In summary, these findings demonstrate that KLF16 plays a significant role in GC progression and could be a new therapeutic target for GC patients.

Three new 2,5-diketopiperazines from the fish intestinal Streptomyces sp. MNU FJ-36.

The gut actinobacteria of marine-inhabited fish is one of the most important reservoirs of novel natural products. Currently, the Streptomyces sp. MNU FJ-36 was isolated from the intestinal fabric of Katsuwonus sp. and determined by 16S rRNA analysis. From the cultures of the S. sp. MNU FJ-36, three new 2,5-diketopiperazines (2,5-DKPs) were discovered and identified as 3-(3-hydroxy-4-methoxybenzyl)-6-isobutyl-2,5-diketopiperazine (1), 3-(1,3-benzodioxol-5-ylmethyl)-6-isobutyl-2,5-diketopiperazine (2) and 3-(1,3-benzodioxol-5-ylmethyl)-6-isopropyl-2,5-diketopiperazine (3). Their structures were elucidated on the basis of spectroscopic data analysis. All the compounds were also evaluated for their inhibitory activity against P388, A-549 and HCT-116 cell lines with the MTT assay.