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Updated: Jun 6, 2026
Next Generation Sequencing for the Detection of Actionable Mutations in Solid and Liquid Tumors
Published on: September 20, 2016
Both gene amplification and allelic loss occur at 14q13.3 in lung cancer
Thomas Harris1, Qiulu Pan, Juan Sironi
1Department of Pathology, Albert Einstein College of Medicine, Montefiore Medical Center, Bronx, New York 10461, USA.
Purpose:
Because loss of Nkx2-8 increases lung cancer in the mouse, we studied suppressive mechanisms in human lung cancer.
Experimental Design:
NKX2-8 is located within 14q13.3, adjacent to its close relative TTF1/NKX2-1. We first analyzed LOH of 14q13.3 in forty-five matched human lung cancer and control specimens. DNA from tumors with LOH was then analyzed with high-density single-nucleotide polymorphism (SNP) arrays. For correlation with this genetic analysis, we quantified expression of Nkx2-8 and TTF1 mRNA in tumors. Finally, suppressive function of Nkx2-8 was assessed via colony formation assays in five lung cancer cell lines.
Results:
Thirteen of forty-five (29%) tumors had LOH. In six tumors, most adenocarcinomas, LOH was caused by gene amplification. The 0.8-Mb common region of amplification included MBIP, SFTA, TTF1, NKX2-8, and PAX9. In 4 squamous or adenosquamous cancers, LOH was caused by deletion. In three other tumors, LOH resulted from whole chromosome mechanisms (14(-), 14(+), or aneuploidy). The 1.2-Mb common region of deletion included MBIP, SFTA, TTF1, NKX2-8, PAX9, SLC25A21, and MIPOL1. Most tumors had low expression of Nkx2-8. Nevertheless, sequencing did not show NKX2-8 mutations that could explain the low expression. TTF1 overexpression, in contrast, was common and usually independent of Nkx2-8 expression. Finally, stable transfection of Nkx2-8 selectively inhibited growth of H522 lung cancer cells.
Conclusions:
14q13.3, which contains NKX2-8, is subject to both amplification and deletion in lung cancer. Most tumors have low expression of Nkx2-8, and its expression can inhibit growth of some lung cancer cells.
Insights
Loss of Nkx2-8 gene expression is common in lung cancer, and its reintroduction can inhibit tumor cell growth. This suggests Nkx2-8 acts as a tumor suppressor in lung cancer.
Area of Science:
- Genetics
- Oncology
- Molecular Biology
Background:
- Loss of Nkx2-8 gene function is linked to increased lung cancer incidence in mouse models.
- Understanding suppressive mechanisms is crucial for developing targeted lung cancer therapies.
Purpose of the Study:
- Investigate the role of Nkx2-8 in human lung cancer.
- Analyze genetic alterations and expression patterns of NKX2-8 and its related gene TTF1 in lung tumors.
- Determine the functional impact of Nkx2-8 on lung cancer cell growth.
Main Methods:
- Analysis of loss of heterozygosity (LOH) at 14q13.3 in 45 human lung tumors using SNP arrays.
- Quantification of Nkx2-8 and TTF1 mRNA expression.
- Assessment of Nkx2-8's suppressive function via colony formation assays in lung cancer cell lines.
Main Results:
- LOH at 14q13.3, encompassing NKX2-8, was observed in 29% of tumors due to amplification or deletion.
- Most tumors exhibited low Nkx2-8 expression, without detectable mutations.
- TTF1 overexpression was frequent and generally independent of Nkx2-8 levels.
- Nkx2-8 reintroduction inhibited growth in specific lung cancer cell lines (H522).
Conclusions:
- The 14q13.3 locus, containing NKX2-8, undergoes genetic alterations (amplification/deletion) in lung cancer.
- Reduced Nkx2-8 expression is prevalent in lung tumors.
- Nkx2-8 demonstrates tumor-suppressive activity, inhibiting the growth of certain lung cancer cells.
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