Expression of estrogen receptor beta and overall survival in non-small cell lung cancer patients: Protocol for a systematic review and meta-analysis of cohort studies

Ferrozoles: Ferrocenyl derivatives of letrozole with dual effects as potent aromatase inhibitors and cytostatic agents

In the treatment of hormone-dependent cancers, aromatase inhibitors (AI) are receiving increased attention due to some undesirable effects such as the risk of endometrial cancer and thromboembolism of SERMs (selective estrogen receptor modulators). Letrozole is the most active AI with 99% aromatase inhibition. Unfortunately, this compound also exhibits some adverse effects such as hot flashes and fibromyalgias. Therefore, there is an urgent need to explore new types of AIs that retain the same-or even increased-antitumor ability. Inspired by the letrozole structure, a set of new derivatives has been synthesized that include a ferrocenyl moiety and different heterocycles. The derivative that contains a benzimidazole ring, namely compound 6, exhibits a higher aromatase inhibitory activity than letrozole and it also shows potent cytostatic behavior when compared to other well-established aromatase inhibitors, as demonstrated by dose-response, cell cycle, apoptosis and time course experiments. Furthermore, 6 promotes the inhibition of cell growth in both an aromatase-dependent and -independent fashion, as indicated by the study of A549 and MCF7 cell lines. Molecular docking and molecular dynamics calculations on the interaction of 6 or letrozole with the aromatase binding site revealed that the ferrocene moiety increases the van der Waals and hydrophobic interactions, thus resulting in an increase in binding affinity. Furthermore, the iron atom of the ferrocene fragment can form a metal-acceptor interaction with a propionate fragment, and this results in a stronger coupling with the heme group-a possibility that is consistent with the strong aromatase inhibition of 6.

Loss of Frizzled 9 in Lung Cells Alters Epithelial Phenotype and Promotes Premalignant Lesion Development

The transmembrane receptor Frizzled 9 (FZD9) is important for fetal neurologic and bone development through both canonical and non-canonical WNT/FZD signaling. In the adult lung, however, Fzd9 helps to maintain a normal epithelium by signaling through peroxisome proliferator activated receptor γ (PPARγ). The effect of FZD9 loss on normal lung epithelial cells and regulators of its expression in the lung are unknown. We knocked down FZD9 in human bronchial epithelial cell (HBEC) lines and found that downstream EMT targets and PPARγ activity are altered. We used a FZD9-/- mouse in the urethane lung adenocarcinoma model and found FZD9-/- adenomas had more proliferation, increased EMT signaling, decreased activation of PPARγ, increased expression of lung cancer associated genes, increased transformed growth, and increased potential for invasive behavior. We identified PPARγ as a transcriptional regulator of FZD9. We also demonstrated that extended cigarette smoke exposure in HBEC leads to decreased FZD9 expression, decreased activation of PPARγ, and increased transformed growth, and found that higher exposure to cigarette smoke in human lungs leads to decreased FZD9 expression. These results provide evidence for the role of FZD9 in lung epithelial maintenance and in smoking related malignant transformation. We identified the first transcriptional regulator of FZD9 in the lung and found FZD9 negative lesions are more dangerous. Loss of FZD9 creates a permissive environment for development of premalignant lung lesions, making it a potential target for intervention.

Circular RNA hsa_circ_0072309 inhibits non-small cell lung cancer progression by sponging miR-580-3p

Objective: Non-small cell lung cancer (NSCLC) continues to top the list of cancer mortalities worldwide. Early diagnosis and therapeutic interventions targeting NSCLC is becoming the world’s significant challenge. Circular RNAs (circRNAs) are emerging as a group of potential cancer biomarkers.

Materials and methods: Quantitative real-time PCR (qRT-PCR) was employed to examine the expression of circ_0072309 in NSCLC tissues and cell lines. Cell counting kit 8 (CCK-8), wound healing and Transwell assays were used to analyze cell proliferation, migration and invasion in A549 and H1299 cells. The relationship between circ_0072309 and miR-580-3 was analyzed by Luciferase reporter and RNA pull down assays.

Results: We screened circ_0072309 from Gene Expression Omnibus and found that circ_0072309 was lowly expressed in NSCLC tissues and cell lines. The transfection of circ_0072309-overexpressing vector significantly suppressed the cell proliferation, migration and invasion in A549 and H1299 cells. We predicted that miR-580-3p is a target of circ_0072309 by using publicly available bioinformatic algorithms Circinteractome tool and confirmed that circ_0072309 directly bound to miR-580-3p. Furthermore, the addition of miR-580-3p mitigated the blockage of cell proliferation, migration and invasion induced by circ_0072309.

Conclusions: These data showed that circ_0072309 inhibits the progression of NSCLC progression via blocking the expression of miR-580-3p. These findings revealed the anti-tumor role of circ_0072309 during the development of NSCLC and provided a novel diagnostic biomarker and potential therapy for NSCLC.