Methylation of ERß 5'-untranslated region attenuates its inhibitory effect on ERα gene transcription and promotes the initiation and progression of papillary thyroid cancer.

Normal thyroid tissue displays a prevalent expression of ERß than ERα, which drastically turns upside down in the initiation and progression of papillary thyroid cancer (PTC). The underlying molecular mechanism of this phenomenon remains unclear. Here, we demonstrated that ERα and ERß were coexpressed in human thyroid tissues and cells. ERα mRNA (A-1) and ERß mRNA (0N-1), transcribed from Promoter A of ERα gene and Promoter 0N of ERß gene, respectively, were the major mRNA isoforms which mainly contributed to total ERα mRNA and total ERß mRNA in human thyroid-derived cell lines and tissues. The expression levels of ERα mRNA (A-1) and total ERα mRNA were gradually increased, and those of ERß mRNA (0N-1) and total ERß mRNA were decreased by degree in the initiation and progression of PTC. No aberrant DNA methylation of ERα 5'-untranslated region was involved in its up-regulation; however, aberrant DNA methylation in Promoter 0N and Exon 0N of ERß gene was found to be involved in its down-regulation in the initiation and progression of PTC. ERß can repress ERα gene transcription via recruitment of NCoR and displacement of RNA polymerase II at the Sp1 site in ERα Promoter A-specific region in thyroid-derived cells. It is suggested that DNA methylation of CpG islands in Promoter 0N and Exon 0N of ERß gene leads to a decreased ERß gene expression, which attenuates its inhibitory effect on ERα gene transcription and results in an increased ERα gene expression, cell proliferation, initiation, and progression of PTC.

The role of small RNAs in resistant melon cultivar against Phelipanche aegyptiaca parasitization.

Bidirectional trans-kingdom RNA silencing, a pivotal factor in plant-pathogen interactions, remains less explored in plant host-parasite dynamics. Here, using small RNA sequencing in melon root systems, we investigated microRNA (miRNA) expression variation in resistant and susceptible cultivars pre-and post-infection by the parasitic plant, broomrape. This approach revealed 979 known miRNAs and 110 novel miRNAs across 110 families. When comparing susceptible (F0) and resistant (R0) melon lines with broomrape infection (F25 and R25), 39 significantly differentially expressed miRNAs were observed in F25 vs. F0, 35 in R25 vs. R0, and 5 in R25 vs. F25. Notably, two miRNAs consistently exhibited differential expression across all comparisons, targeting genes linked to plant disease resistance. This suggests their pivotal role in melon's defense against broomrape. The target genes of these miRNAs were confirmed via degradome sequencing and validated by qRT-PCR, ensuring reliable sequencing outcomes. GO and KEGG analyses shed light on the molecular functions and pathways of these differential miRNAs. Furthermore, our study unveiled four trans-kingdom miRNAs, forming a foundation for exploring melon's resistance to broomrape.

In vitro and in vivo antioxidant activities of inulin.

This study was designed to investigate the in vitro and in vivo antioxidant activities of inulin. The in vitro assays demonstrated that the antioxidant activities of inulin, including the DPPH radical scavenging activity, ABTS scavenging activity and ferric reducing power, were weak and significantly lower than those of Vitamin C (P < 0.05). The influence of dietary supplementation with inulin on the antioxidant status of laying hens was evaluated with in vivo antioxidant assays. The results indicated that inulin supplementation quadratically improved the egg production rate of the laying hens (P < 0.01). The antioxidant enzyme activities in the serum, including SOD, CAT, and GSH-Px, and the total antioxidant capacity increased quadratically as inulin levels increased (P < 0.001). The levels of MDA in the serum decreased quadratically as inulin levels increased (P < 0.001). These findings suggest that inulin has the potential to improve the antioxidant status of laying hens.

Expression of TGF-ß1, SNAI1 and MMP-9 is associated with lymph node metastasis in papillary thyroid carcinoma.

TGF-ß1, SNAI1 and MMP-9 are implicated in tumor invasion and metastasis. The purpose of this study was to examine TGF-ß1, SNAI1 and MMP-9 expression in papillary thyroid carcinoma (PTC), and to assess association of TGF-ß1, SNAI1 and MMP-9 expression with several clinicopathological indicators of PTC. TGF-ß1, SNAI1 and MMP-9 protein expression in 83 PTCs and their matched normal thyroid specimens were analyzed using immunohistochemistry. The mRNA expression levels of TGF-ß1, SNAI1 and MMP-9 in 12 fresh PTC specimens with lymph node metastasis (LNM), 12 fresh PTC specimens without LNM and their matched normal thyroid specimens were assessed by real-time RT-PCR. The results showed that the mRNA and protein expression levels of TGF-ß1, SNAI1 and MMP-9 were significantly higher in PTCs than in their matched normal thyroid tissues. There were not significant differences in TGF-ß1, SNAI1 and MMP-9 protein expression relative to age, gender, tumor size and TNM stage, except for MMP-9 whose protein expression correlated with tumor size. However, high mRNA and protein expression levels of TGF-ß1, SNAI1 and MMP-9 were significantly correlated with LNM. Furthermore, TGF-ß1, SNAI1 and MMP-9 protein expression were significantly correlated with one another. Concomitant expression of any two or all of the three molecules had stronger correlation with LNM than did each alone. Collectively, the present results indicate that immunohistochemical and real-time RT-PCR evaluation of TGF-ß1, SNAI1 and MMP-9 expression in PTC may be useful to predict the risk of LNM in PTC patients.

17ß-estradiol promotes the invasion and migration of nuclear estrogen receptor-negative breast cancer cells through cross-talk between GPER1 and CXCR1.

G protein-coupled estrogen receptor 1 (GPER1) is widely expressed in human breast cancers correlating with increased tumor size and malignancy. Although estrogen signaling via GPER1 was extensively studied in recent years, the underlying molecular mechanism of GPER1-associated metastasis of breast cancer still remains unclear. In this study, the main aims were focused on the potential role of GPER1 in regulating migration and invasion of nuclear estrogen receptor (ER)-negative breast cancer cells upon 17ß-estradiol (E2) stimulation and the involved signaling pathway. Key events in estrogen signaling were chosen for our studies, such as the activation of ERK and AKT, nuclear translocation of NF-κB and secretion of Interleukin-8 (IL-8). The migration and invasion activities upon E2 stimulation were also examined in ER-negative SKBR3 and BT-20 breast cancer cells. Compared with ER-positive MCF-7 breast cancer cells, both SKBR3 and BT-20 cells had very similar expression of GPER1, but relatively high expression of CXC receptor-1 (CXCR1), which is considered as an active regulator for cancer metastasis upon binding IL-8. Results showed that E2 facilitated the activation of ERK, AKT and NF-κB, which could be significantly attenuated by GPER1 blockage or knock-down in both SKBR3 and BT-20 cells. Moreover, increased secretion of IL-8 induced by E2 was also inhibited either by specific inhibitors for GPER1, ERK, AKT, and NF-κB, or by knock-down for GPER1. Furthermore, E2 could activate the migration and invasion of both SKBR3 and BT-20 cells, which in turn could also be inhibited by blocking GPER1, ERK, AKT, NF-κB, and CXCR1, respectively, or knock-down for GPER1 and CXCR1. In conclusion, we demonstrated that estrogen signaling via GPER1 associated with the metastasis of breast cancer, which might be through GPER1/ERK&AKT/NF-κB/IL-8/CXCR1 cascade. The cross-talk between GPER1 and CXCR1 could be another potential target for the therapy of metastatic breast cancer.