1447 - The role of Pim-1 in the development and progression of papillary thyroid carcinoma

Background

Pim-1 is an oncogene and has been proved to play pivotal role in proliferation, apoptosis and angiogenesis. Thyroid cancer represents the most common malignancy in the endocrine system and displays a marked increase in the incidence in recent years. Papillary thyroid cancer (PTC) is among the most frequent thyroid malignancies and accounts for more than 85%. Therefore, it is worthwhile to discuss the function of Pim-1 in the development and progression of PTC.

Methods

Gene set enrichment analysis (GSEA) of Pim-1 in the PTC was performed on the TCGA databases. 177 PTC paraffin blocks were selected to make the tissue microarrays and the levels of Pim-1 protein was investigated by immunohistochemistry. Meanwhile, one of the Pim-1 kinase inhibitor, SGI-1776, was used to evaluate the function of Pim-1 on the PTC cell BCPAP and TPC-1. CCK-8 and colony formation assay was carried out to measure the cell proliferation. Apoptosis rate and migration capacity were determined by flow cytometry and wound-healing methods respectively.

Results

GSEA results revealed that Pim-1 expression was significantly associated with the immune system of PTC. IHC result showed that Pim-1 was overexpressed in the PTC tissues compared with normal adjacent tissues. Meanwhile, Pim-1 had a significant relationship with the T-stage, lymph node involvement, capsule invasion and gender. Female patients and patients with higher T-stage, positive lymph node involvement, positive capsule invasion have a higher Pim-1 level. After SGI-1776 treatment, Pim-1 expressions were obviously downregulated in both BCPAP and TPC-1. Decreased Pim-1 led to the proliferation depression, apoptosis rate elevation and the migration capacity reduction in both cell lines.

Conclusions

Taken together, our current data showed the important role of Pim-1 in the tumorigenesis of PTC. High Pim-1 level linked to immune status and aggressive malignant behavior of PTC. It was also suggested that PIM-1 kinase might be a novel molecular biomarker of PTC.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

Zhejiang Province Natural Science Foundation of China.

Disclosure

All authors have declared no conflicts of interest.