Silencing the FOLR2 Gene Inhibits Cell Proliferation and Increases Apoptosis in the NCI-H1650 Non-Small Cell Lung Cancer Cell Line via Inhibition of AKT/Mammalian Target of Rapamycin (mTOR)/Ribosomal Protein S6 Kinase 1 (S6K1) Signaling

The Protective Role of Transcript-Induced in Spermiogenesis 40 in Cerebral Ischemia-Reperfusion Injury

Prompt reperfusion after cerebral ischemia is important to maintain neuronal survival and reduce permanent disability and death. However, the resupply of blood can induce oxidative stress, inflammatory response and apoptosis, further leading to tissue damage. Here, we report the versatile biological roles of transcript-induced in spermiogenesis 40 (Tisp40) in ischemic stroke. We found that the expression of Tisp40 was upregulated in ischemia/reperfusion-induced brain tissues and oxygen glucose deprivation/returned -stimulated neurons. Tisp40 deficiency increased the infarct size and neurological deficit score, and promoted inflammation and apoptosis. Tisp40 overexpression played the opposite role. In vitro, the oxygen glucose deprivation/returned model was established in Tisp40 knockdown and overexpression primary cultured cortical neurons. Tisp40 knockdown can aggravate the process of inflammation and apoptosis, and Tisp40 overexpression ameliorated the aforementioned processes. Mechanistically, Tisp40 protected against ischemic stroke via activating the AKT signaling pathway. Tisp40 may be a new therapeutic target in brain ischemia/reperfusion injury.

microRNA-622 upregulates cell cycle process by targeting FOLR2 to promote CRC proliferation

BACKGROUND

Epigenetic alterations contribute greatly to the development and progression of colorectal cancer, and effect of aberrant miR-622 expression is still controversial. This study aimed to discover miR-622 regulation in CRC proliferation.

METHODS

miR-622 expression and prognosis were analyzed in clinical CRC samples from Nanfang Hospital. miR-622 regulation on cell cycle and tumor proliferation was discovered, and FOLR2 was screened as functional target of miR-622 using bioinformatics analysis, which was validated via dual luciferase assay and gain-of-function and loss-of-function experiments both in vitro and in vivo.

RESULTS

miR-622 overexpression in CRC indicated unfavorable prognosis and it regulated cell cycle to promote tumor growth both in vitro and in vivo. FOLR2 is a specific, functional target of miR-622, which negatively correlates with signature genes in cell cycle process to promote CRC proliferation.

CONCLUSIONS

miR-622 upregulates cell cycle process by targeting FOLR2 to promote CRC proliferation, proposing a novel mechanism and treatment target in CRC epigenetic regulation of miR-622.

Emerging roles for folate receptor FOLR1 in signaling and cancer

Folates are B vitamins that function in one-carbon metabolism. Folate receptors are one of three major types of folate transporters. The folate receptors FOLR1 and FOLR2 are overexpressed in multiple cancers. The overexpression of FOLR1 is often associated with increased cancer progression and poor patient prognosis. There is emerging evidence that FOLR1 is involved in signaling pathways that are independent of one-carbon metabolism. Recent publications implicate a direct role of FOLR1 in three signaling pathways: JAK-STAT3, ERK1/2, and as a transcription factor. Six other signaling pathways have been proposed to include FOLR1, but these currently lack sufficient data to infer a direct signaling role for FOLR1. We discuss the data that support noncanonical roles for FOLR1, and its limitations.

pH-sensitive multi-drug liposomes targeting folate receptor β for efficient treatment of non-small cell lung cancer

Non-small cell lung cancer (NSCLC) is the leading cause of lung cancer-related deaths worldwide. Tumor-associated macrophages (TAMs), which can be polarized into tumor-promoting M2 phenotype, overexpress folate receptor beta (FRβ) and are associated with poor prognosis in NSCLC. In addition, calpain-2 (CAPN2) is overexpressed in NSCLC and is involved in tumor growth. To improve the anticancer efficacy of drugs and reduce their side effects in the treatment of NSCLC, it is important to develop smart drug delivery systems with specific targeting ability and controlled release mechanisms. In this study, FRβ-targeted pH-sensitive liposomes were designed as carriers to ensure efficient drug delivery and acid-responsive release in NSCLC cells. Folate-mediated targeting of FRβ in M2 TAMs and NSCLC cells effectively inhibited tumor growth and the stimulus-responsive drug release reduced the toxic side effects of the drug. The combination of doxycycline (anti-CAPN2) and docetaxel (anticancer drug) showed a synergistic inhibitory effect on tumor growth by suppressing CAPN2 expression.

Celastrus Orbiculatus Extracts Inhibit the Metastasis through Attenuating PI3K/Akt/mTOR Signaling Pathway in Human Gastric Cancer

BACKGROUND

Rapamycin receptor inhibitors have been applied in the clinic and achieved satisfactory therapeutic effect recently. The mechanisms did not clearly show how the Celastrus Orbiculatus Extracts (COE) inhibited the expression of the mammalian Target of Rapamycin (mTOR) in human gastric cancer cells. The aim of this study was to investigate whether the COE inhibited the metastasis through the mTOR signaling pathway in human gastric cancer MGC-803 cells.

METHODS

The abnormal expression level of mTOR protein was detected by immunohistochemistry in human gastric cancer tissue. The MGC-803/mTOR- cells were constructed by knockdown of mTOR using lentivirus infection technique. The human gastric cancer MGC-803/mTOR- cells were treated with different concentrations (20, 40, 80 μg/ml) of COE for 24 hours. The ability of cell metastasis was analyzed by the cell invasion and migration assay. The expression levels of PI3K/Akt/mTOR signaling pathway were detected by Western Blotting.

RESULTS

COE inhibited the proliferation, invasion and migration of MGC-803/mTOR- cells in a concentrationdependent manner. The expression of E-cadherin protein increased, and the expression of N-cadherin and Vimentin decreased simultaneously in the MGC-803/mTOR- cells. 4EBP1, p-4EBP1, P70S6k, p-P70S6k, mTOR, p-mTOR, PI3K and Akt proteins in MGC-803/mTOR- cells were reduced in a dose-dependent manner.

CONCLUSION

COE could not only inhibit cell growth, invasion and migration, but also inhibit the epithelialmesenchymal transition of gastric cancer cells. The molecular mechanism of COE inhibited the metastasis which may be related to the PI3K/Akt/mTOR signal pathway. This study provides ideas for the development of new anti-gastric cancer drugs.