The gene expression of GPER1 is low in fresh samples of papillary thyroid carcinoma (PTC), and in silico analysis

Oestrogen receptor-independent actions of oestrogen in cancer

Oestrogen, the primary female sex hormone, plays a significant role in tumourigenesis. The major pathway for oestrogen is via binding to its receptor [oestrogen receptor (ERα or β)], followed by nuclear translocation and transcriptional regulation of target genes. Almost 70% of breast tumours are ER + , and endocrine therapies with selective ER modulators (tamoxifen) have been successfully applied. As many as 25% of tamoxifen-treated patients experience disease relapse within 5 years upon completion of chemotherapy. In such cases, the ER-independent oestrogen actions provide a plausible explanation for the resistance, as well as expands the existing horizon of available drug targets. ER-independent oestrogen signalling occurs via one of the following pathways: signalling through membrane receptors, oxidative catabolism giving rise to genotoxic metabolites, effects on mitochondria and redox balance, and induction of inflammatory cytokines. The current review focuses on the non-classical oestrogen signalling, its role in cancer, and its clinical significance.

The Tumor Microenvironment and the Estrogen Loop in Thyroid Cancer

Thyroid cancer (TC) cells employ multiple signaling pathways, such as PI3K/AKT/mTOR and RAS/Raf/MAPK, fostering cell proliferation, survival and metastasis. Through a complex interplay with immune cells, inflammatory mediators and stroma, TC cells support an immunosuppressive, inflamed, pro-carcinogenic TME. Moreover, the participation of estrogens in TC pathogenesis has previously been hypothesized, in view of the higher TC incidence observed among females. In this respect, the interactions between estrogens and the TME in TC could represent a relevant, unexplored area of research. We thereby collectively reviewed the available evidence concerning the potential carcinogenic role of estrogens in TC, specifically focusing on their crosstalk with the TME.

Comparative G-Protein-Coupled Estrogen Receptor (GPER) Systems in Diabetic and Cancer Conditions: A Review

For many patients, diabetes Mellitus and Malignancy are frequently encountered comorbidities. Diabetes affects approximately 10.5% of the global population, while malignancy accounts for 29.4 million cases each year. These troubling statistics indicate that current treatment approaches for these diseases are insufficient. Alternative therapeutic strategies that consider unique signaling pathways in diabetic and malignancy patients could provide improved therapeutic outcomes. The G-protein-coupled estrogen receptor (GPER) is receiving attention for its role in disease pathogenesis and treatment outcomes. This review aims to critically examine GPER' s comparative role in diabetes mellitus and malignancy, identify research gaps that need to be filled, and highlight GPER's potential as a therapeutic target for diabetes and malignancy management. There is a scarcity of data on GPER expression patterns in diabetic models; however, for diabetes mellitus, altered expression of transport and signaling proteins has been linked to GPER signaling. In contrast, GPER expression in various malignancy types appears to be complex and debatable at the moment. Current data show inconclusive patterns of GPER expression in various malignancies, with some indicating upregulation and others demonstrating downregulation. Further research should be conducted to investigate GPER expression patterns and their relationship with signaling pathways in diabetes mellitus and various malignancies. We conclude that GPER has therapeutic potential for chronic diseases such as diabetes mellitus and malignancy.

LncRNA ABHD11-AS1 promotes tumor progression in papillary thyroid carcinoma by regulating EPS15L1/EGFR signaling pathway

OBJECTIVES

lncRNA ABHD11 antisense RNA 1 (ABHD11-AS1) acts as an oncogene involved in papillary thyroid carcinoma (PTC) occurrence and progression. ABHD11-AS1 exerts biologic functions by some miRNAs and proteins to regulate multiple targets. Identification of novel mechanism of ABHD11-AS1 could be helpful in therapeutic targeting for PTC treatment.

METHODS

Differentially expressed lncRNAs were selected from TCGA database. qRT-PCR analysis was applied to examine the expression of ABHD11-AS1 in PTC cell lines and tissues. The relationship of ABHD11-AS1 expression and clinicopathological features was analyzed by Kaplan-Meier analysis. Two PTC cell lines (TPC-1 and KTC-1) were transfected with pcDNA 3.1, pcDNA3.1-ABHD11-AS1, si-NC and si-ABHD11-AS1, respectively, to verify the ABHD11-AS1 oncogene-regulating capacity to promote tumor progression. The cell metastasis and proliferation had been evaluated both in vitro and in vivo.

RESULTS

High expression of ABHD11-AS1 was found in PTC tissues (P < 0.01), which was significantly correlated with lymph node metastasis (P < 0.05). ABHD11-AS1 overexpression noticeably promoted cell proliferation, migration, and invasion capabilities, which were obviously decreased upon ABHD11-AS1 knockdown. ABHD11-AS1 positively regulated EGFR/EPS15L1 pathway, as EGFR, EPS15L1, STAT3, and p-STAT3 were activated.

CONCLUSION

ABHD11-AS1 promotes tumor progression in PTC by regulating EPS15L1/EGFR pathway.

Decreased Expression of Estrogen Receptors Is Associated with Tumorigenesis in Papillary Thyroid Carcinoma

Papillary thyroid carcinomas (PTC), which is derived from thyroid follicular cells, is the most commonly differentiated thyroid cancer with sex disparity. However, the role of estrogen receptors (ERs) in the pathogenesis of PTC remains unclear. The present study aimed to determine the association of ER mRNA expression levels with clinicopathologic features in PTC. To that aim, the mRNA levels of ESR1 (ERα66), ESR1 (ERα36), ESR2, and G-protein-coupled estrogen receptor 1 (GPER1) in snap-frozen tissue samples from PTCs and adjacent normal thyroid tissues were determined using quantitative reverse transcription polymerase chain reaction (RT-qPCR), and the correlation between ER mRNA expression levels and clinicopathologic features was analyzed. The expression of ERα66, ERα36, ERβ, and GPER1 was lower in PTC specimens than in adjacent normal thyroid tissues. Moreover, low GPER1 expression was associated with extrathyroidal extension. There was no obvious difference in expression of ERs between PTC specimens from male and female patients. In conclusion, our findings highlight the importance of ERs in PTC tumorigenesis.