Admittedly, lung cancer was related to genes' overexpression and mutations. It is highly significant to identify therapeutic targets and novel biomarkers for the development and prognosis of lung cancer. The present studies based on the public databases indicated that IGF2BPs expression was increased in lung cancer tissues compared to normal lung tissues, which was also confirmed by Q-PCR. Meanwhile, it was involved in pathological tumor stages. Moreover, high mRNA expressions of IGF2BP1/2/3 were found to be significantly associated with shorter OS and FP in lung cancer patients. Additionally, a high mutation rate of IGF2BPs (24%) was also found in patients with lung cancer. These results revealed that IGF2BPs played a role in lung cancer. Our findings may help to improve the accuracy of the prognosis and survival in lung cancer patients.
IGF2BP1 serves as a post-transcriptional fine-tuner that regulates the expression of some essential mRNA targets needed to control of tumor cell proliferation, growth, invasion, and chemo-resistance, connecting with a poor survival and metastasis in cancers [23]. For example, IGF2BP1 promotes G1/S cell cycle transition to result in cancer by relying on 3'UTR-, miRNA- and m6A-dependent regulation of the checkpoint like E2F1 [24]. Previous studies have shown that IGF2BP1 is highly expressed in lung cancer, predicting poor prognosis for lung cancer patients. Study carried out by Zhang et al. showed IGF2BP1 silencing inhibited cancer cell proliferation, migration and invasion, as well as induced cell cycle arrest and apoptosis through down-regulating Netrin-1 expression [25]. Similarly, Huang et al. indicated that low IGF2BP1 expression was negatively correlated with pathological stage and lymph node metastasis, and its status is an independent prognostic factor for lung cancer after surgical resection [26]. Our results are consistent with the previous ones, showing the high mRNA expressions of IGF2BP1 was found in lung cancer tissues. Moreover, the high expression of IGF2BP1 was significantly related to tumor stages and the shorter OS and FP. All these results showed that IGF2BP1 contributed to the development and progression of lung cancer, and it might serve as potential therapeutic target and survival biomarker for patients with lung cancer.
Similarly, up-regulation of IGF2BP2 by multiple mechanisms promotes development and proliferation in multiple cancers. Mechanistically, IGF2BP2 activate the PI3K/Akt signaling pathway for cancer proliferation [27]. Study carried out by Png et al., found that IGF2BP2/IGF-1/IGF-1 receptor signaling pathways might involve in cancer mediated endothelial recruitment, which was a significant feature of metastatic cancer in the tumor microenvironment [28]. Equally, as for lung cancer, identified as a novel direct target of miR-485-5p, depletion of IGF2BP2 significantly inhibited cell proliferation and invasion [29]. In our study, we showed high mRNA expression of IGF2BP2 in lung cancer tissues, significantly associating with tumor stages and the shorter OS and FP. These results indicated that IGF2BP2 was involved in the development and progression of lung cancer, and it might serve as a prognostic biomarker and target for precision therapy of lung cancer patients.
IGF2BP3 sustains cancer cell growth and proliferation while putatively inhibiting apoptosis by a well-established mechanism of action of IGF2BP3 on account of its protection from Let-7 miRNA-mediated decay [30]. Further, Overexpression of IGF2BP3 in lung cancer cells promoted cell proliferation, tumor migration and invasion possibly via attenuating p53 stability [31]. In addition, IGF2BP3 has also been found to repress RNAs and miRNAs of lung cancer cells eiF4E-BP2 to promote the proliferation of cancer cells, and eIF4E encodes a negative regulator of eukaryotic translation initiation factor 4E [32]. Our results further confirm above results with high mRNA expression of IGF2BP3 in lung cancer tissues, significantly relevant with tumor grades and poor prognosis of OS and FP. These results suggest that IGF2BP3 may be a therapeutic target and prognostic biomarker by participating in the development and progression of lung cancer.
Collectively, this work was designed with bioinformatics analysis of multiple data sets directing against IGF2BPs expression level in clinical tissue and its clinical relevance. All data illustrated that IGF2BP1/2/3 hold potential promoting effects on lung cancer. Despite this, some limitations were still present in our study. First, analysis on the transcriptional level could reflect some aspects of tumor progression, but not global changes. We will try our best in the follow-up study to investigate the detailed mechanism between distinct IGF2BPs and lung cancer. Second, further studies consist of larger clinical sample sizes were required to explore and verify the clinical application of the IGF2BPs members in the treatment of lung cancer.