Knockdown of hnRNP A2/B1 inhibits cell proliferation, invasion and cell cycle triggering apoptosis in cervical cancer via PI3K/AKT signaling pathway

Abstract

Cervical cancer is currently one of the major threats to women's health. The overexpression of heterogeneous nuclear ribonucleoprotein A2/B1 (hnRNP A2/B1) as the biomarker has been investigated in various cancers. In our previous study, we found that lobaplatin induced apoptosis and cell cycle arrest via downregulation of proteins including hnRNP A2/B1 in cervical cancer cells. However, the underlying relationship between hnRNP A2/B1 and cervical cancer remained largely unknown. hnRNP A2/B1 knock-down in HeLa and CaSki cells was performed by shRNA transfection. The expression of hnRNP A2/B1 was detected by western blot and Quantitative Real-time PCR. Cell proliferation, migration, invasion and the IC50 of lobaplatin and irinotecan were determined by MTT assay, Transwell assay, Plate colony formation assay and wound healing assay. Flow cytometry was perfomed to investigate cell apoptosis and the cell cycle. The expression of PI3K, AKT, p-AKT, p21, p27, caspase-3, cleaved caspase-3 were revealed by western blot. Nude mouse xenograft model was undertaken with HeLa cells and the xenograft tumor tissue samples were analyzed for the expression of PCNA and Ki-67 by immunohistochemistry and the cell morphology was evaluated by hematoxylin and eosin (H&E). Results revealed that hnRNP A2/B1 was successfully silenced in HeLa and CaSki cells. hnRNP A2/B1 knock-down significantly induced the suppression of proliferation, migration, invasion and also enhancement of apoptosis and reduced the IC50 of lobaplatin and irinotecan. The expression of p21, p27 and cleaved caspase-3 in shRNA group were significantly upregulated and the expression of p-AKT was reduced both in vitro and in vivo. The results of immunohistochemistry showed that PCNA and Ki-67 were significantly downregulated in vivo. The growth of nude mouse xenograft tumor was significantly reduced by hnRNP A2/B1 knock-down. Taken together, these data indicate that inhibition of hnRNP A2/B1 in cervical cancer cells can inhibit cell proliferation and invasion, induce cell-cycle arrestment and trigger apoptosis via PI3K/AKT signaling pathway. In addition, after silencing hnRNP A2/B1 can increase the sensitivity of cervical cancer cells to lobaplatin and irinotecan.

β-Asarone Inhibits Invasion and EMT in Human Glioma U251 Cells by Suppressing Splicing Factor HnRNP A2/B1

“…Accumulating evidence has indicated that hnRNPA2/B1 plays a pivotal role in increasing the metastatic propensity of tumor cells [ 10 , 35 ]. Notably, hnRNPA2/B1 has also been reported as an inducer of EMT in liver [ 13 ], pancreatic [ 36 ], and lung cancer cell lines [ 30 ].…”

β-Asarone Induces Apoptosis and Cell Cycle Arrest of Human Glioma U251 Cells via Suppression of HnRNP A2/B1-Mediated Pathway In Vitro and In Vivo

“…Recently, hnRNP A2/B1 has been described in the regulation of alternative splicing of several tumor suppressors and oncogenes, such as Bcl-x [ 13 , 14 , 15 ], which is an anti-apoptotic protein belonging to the well-known Bcl-2 family. Moreover, accumulating evidence also revealed that suppression of hnRNP A2/B1 induced cell cycle arrest at G1 phase in cervical cancer cells [ 16 ], lung cancer cells [ 17 , 18 ], and human embryonic stem cells [ 19 ], which renders it a potential novel target for tumor therapy.…”

<em>SMAGP</em> a novel biomarker of cervical cancer development and progression

“…Cervical cancer is one of the most serious malignant tumors, and is associated with high rates of morbidity and mortality, particularly in developing countries, including China. 10 , 11 Worldwide, a large number of new cervical cancer cases are diagnosed every year, and more than half of patients diagnosed died from the cancer. 3 Tumor progression involves tumor cell proliferation and metastasis and novel targeted therapeutic strategies are urgently required for patients with cervical cancer.…”