Contribution of Neuropilin-1 in Radiation-Survived Subclones of NSCLC Cell Line H1299.

Kaori Tsutsumi,Haruka Takahashi,Shima Minaki,Takahito Ooshima,Yuta Tadaki,Ayaka Chiba

doi:10.3390/cimb43030085

Abstract

Non-small cell lung cancer (NSCLC) is an aggressive lung cancer accounting for approximately 85% of all lung cancer patients. For the patients with Stages IIIA, IIIB, and IIIC, the 5-year survival is low though with the combination with radiotherapy and chemotherapy. In addition, the occurrence of tumor cells (repopulated tumors) that survive irradiation remains a challenge. In our previous report, we subcloned the radiation-surviving tumor cells (IR cells) using the human NSCLC cell line, H1299, and found that the expression of neuropilin-1 (NRP-1) was upregulated in IR cells by the microarray analysis. Here, we investigated the contribution of neuropilin-1 to changes in the characteristics of IR cells. Although there were no differences in angiogenic activity in the tube formation assay between parental and IR cells, the cell motility was increased in IR cells compared to parental cells in the cell migration assay. This enhanced cell motility was suppressed by pretreatment with anti-NRP-1 antibody. Although further studies are necessary to identify other molecules associated with NRP-1, the increase in cellular motility in IR cells might be due to the contribution of NRP-1. Inhibition of NRP-1 would help control tumor malignancy in radiation-surviving NSCLC.

Highlights

Non-small cell lung cancer (NSCLC) is an aggressive lung cancer and one of the most common causes of death in Japan and other countries worldwide, accounting for approximately 85% of all lung cancer patients [1,2,3]
To confirm the upregulation of NRP-1 mRNA expression according to our previous report by microarray analysis [8], we first performed reverse transcription PCR (RT-PCR, Figure 1A) and compared the relative expression levels of glyceraldehyde-3-phosphate dehydrogenase mRNA between H1299-IR and parental cells, which are the original cells of the IR cells (Parent) (Figure 1B)
The results show that the expression of NRP-1 mRNA was 1.3-fold higher in IR cells than in the parental H1299 cells (Figure 1A,B)

Summary

Introduction

Non-small cell lung cancer (NSCLC) is an aggressive lung cancer and one of the most common causes of death in Japan and other countries worldwide, accounting for approximately 85% of all lung cancer patients [1,2,3]. The standard therapy for the localized small NSCLC (Stage I) is surgery with a high survival rate and for inoperable Stage I patients, stereotactic ablative radiotherapy lead a good overall survival [4]. We established the model-cells of the repopulated tumor cells after radiotherapy (IR cells) using a human NSCLC cell line (H1299) and reported an upregulated and downregulated gene using comprehensive microarray analysis, and found increased cellular motility and invasiveness before irradiation [8,9]. We focused on neuropilin-1 (NRP-1) among the upregulated genes in the IR cells that survived 10 Gy of X-ray irradiation, that was 2.4-fold upregulated than the original tumor cells in microarray analysis [8]

Methods

Results

Conclusion