Overexpression Of ERβ Participates In The Progression Of Liver Cancer Via Inhibiting The Notch Signaling Pathway

Downregulation of HOXA11 enhances endometrial cancer malignancy and cisplatin resistance via activating PTEN/AKT signaling pathway

PURPOSE

Endometrial cancer is the most common malignant tumor of female genital system worldwide. Homeobox A11 (HOXA11) is an evolutionarily conserved Homeobox gene closely implicated in carcinogenesis. However, the mechanisms of HOXA11 in the progression and cisplatin resistance of endometrial cancer remain unclear.

METHODS

The expression of HOXA11 was analyzed based on 548 endometrial cancer and 35 control tissues from The Cancer Genome Atlas (TCGA) database. Transwell assay was performed to investigate the effect of HOXA11 on endometrial cell migration and invasion. TUNEL staining was carried out to assay the role of HOXA11 in endometrial cell apoptosis. Western blot was employed to detect the protein levels of B cell lymphoma-2 (Bcl-2), Bcl-2 associated X (Bax), cleaved caspase-3, matrix metalloproteinase-2/9 (MMP/9), phosphatase and tensin homolog (PTEN), protein kinase B (AKT) and p-AKT.

RESULTS

TCGA data showed that HOXA11 expression was significantly down-regulated in endometrial cancer tissue samples. The overexpression of HOXA11 promoted the apoptosis, but inhibited the proliferation, migration and invasion of endometrial cancer cells. HOXA11 knockdown with small interfering RNA (siRNA) considerably repressed cell apoptosis, while promoted cell proliferation, migration, and invasion through PTEN/AKT signaling pathway. Interestingly, HOXA11 was lowly expressed in Ishikawa cells treated with cisplatin. In addition, HOXA11 knockdown increased the resistance of endometrial cancer to cisplatin through activating PTEN/AKT signaling pathway.

CONCLUSION

Low HOXA11 expression may promote the proliferation, migration, invasion of endometrial cancer cells, and increase their resistance to cisplatin through activating PTEN/AKT pathway.

Effect of silibinin on ethanol- or acetaldehyde-induced damge of mouse primary hepatocytes in vitro

Silibinin, one of the flavonoids isolated from milk thistle seeds of Silybum marianum, has hepatoprotective properties against toxins in clinical. However, the detailed mechanisms have remained unclear. This study investigates the underlying mechanism of silibinin in the protection against ethanol- or acetaldehyde-induced damage of neonatal mouse primary hepatocytes in vitro. The results show that ethanol inhibited proliferation of hepatocytes in a time (12, 24, 36 h) and dose-dependent (0-800 mM) manner. However, silibinin did not show protective effect on ethanol (500 mM)-induced suppression of hepatocyte proliferation. Acetaldehyde, the toxic metabolite of ethanol, appearing immediately in individuals after drink also inhibited the proliferation of hepatocytes in a dose-dependent (0-12 mM) manner. Surprisingly, silibinin significantly increased the cell viability and reduced the leakage of alanine amino transferase (ALT) and aspartate amino transferase (AST) in acetaldehyde-treated hepatocytes, suggesting that silibinin protected cell injury caused by acetaldehyde treatment. The apoptosis-inducing effect of acetaldehyde was demonstrated by the increased number of cells in sub-G1 phase as well as caspase-3 activation. Further study shows that acetaldehyde induced autophagy in the hepatocytes. The autophagy inhibitors, 3-Methyladenine (3-MA) and chloroquine (CQ), further decreased the viability of cells treated with acetaldehyde, suggesting that autophagy plays a protective role against apoptosis. Consistently, silibinin (20 μM) significantly reduced the activation of caspase 3 or apoptosis and increased the conversion of LC3-I to LC3-II or autophagy. Taken together, it is concluded that silibinin does not repress the ethanol- induced hepatocyte injury, whereas silibinin reduces acetaldehyde-caused hepatocyte injury through down-regulation of apoptosis and up-regulation of autophagy.

Endocrine Disruptor Bisphenol A (BPA) Triggers Systemic Para-Inflammation and is Sufficient to Induce Airway Allergic Sensitization in Mice

Allergic airway diseases are accompanied by increased permeability and an inflammatory state of epithelial barriers, which are thought to be susceptible to allergen sensitization. Although exogenous drivers (proteases, allergens) of epithelial barrier disruption and sensitization are well studied, endogenous contributors (diet, xenobiotics, hormones, and metabolism) to allergic sensitization are much less understood. Xenoestrogens are synthetic or natural chemical compounds that have the ability to mimic estrogen and are ubiquitous in the food and water supply of developed countries. By interfering with the estrogen produced by the endocrine system, these compounds have the systemic potential to disrupt the homeostasis of multiple tissues. Our study examined the potential of prototypical xenoestrogen bisphenol A (BPA) to disrupt epithelial homeostasis in vitro and promote allergic responses in vivo. We found that BPA exposure in epithelial cultures in vitro significantly inhibited epithelial cell proliferation and wound healing, as well as promoted the expression of the innate alarmin cytokine TSLP in a time-and dose-dependent manner. In vivo, the exposure to BPA through water supply or inhalation induced a systemic para-inflammatory response by promoting the expression of innate inflammatory mediators in the skin, gut, and airway. In a murine tolerogenic antigen challenge model, chronic systemic exposure to BPA was sufficient to induce airway sensitization to innocuous chicken egg ovalbumin in the complete absence of adjuvants. Mechanistic studies are needed to test conclusively whether endocrine disruptors may play an upstream role in allergic sensitization via their ability to promote a para-inflammatory state.