No abstract

Non‐small‐cell lung cancer (NSCLC) accounts for the majority of the lung cancer cases that have become a leading cause of cancer deaths worldwide. Overexpression of transcription factor forkhead box M1 (FOXM1) is involved in the inauspicious development of several types of cancer, including lung tumor aggressiveness. Our laboratory has previously found that MED28, a Mediator subunit for transcriptional activation, modulates cell growth, epithelial‐mesenchymal transition, migration, and invasion in human breast cancer cells. The objective of the current study is to investigate the potential role of MED28 and FOXM1 in NSCLC. In addition to A549 and PC9 cells, we also used a doxycycline‐inducible system to generate FOXM1‐overexpressed A549‐DN cells, and we explored the connection of MED28 with FOXM1 and their effect on migration. Herein, we report that the increased expression levels of both MED28 and FOXM1 elevated the expression of matrix metalloproteinase 2 (MMP2), a metastasis marker, which enhanced cell migration and matrigel invasion of NSCLC cells. Furthermore, MED28 interacted with FOXM1, and both exhibited a mutual effect on the expression and subcellular localization. Moreover, MED28 small interfering RNA‐mediated MMP2 gene suppression could be attenuated by inducible expression of a constitutively active form of FOXM1, which consequently restored the migration and invasion ability of NSCLC cells. Our data indicate that MED28 interacts with FOXM1, and each affects the expression and localization of the other, and, more importantly, both regulate MMP2‐dependent migration and invasion in human lung cancer cells.

A truncated Bacillus sp. TS-23 alpha-amylase gene lacking 96 and 294 bp at its 5' and 3' end respectively was prepared by polymerase chain reaction and cloned into Escherichia coli expression vector, pQE-30, under the control of T5 promoter. SDS-PAGE and activity staining analyses showed that the His6-tagged amylase had a molecular mass of approximately 54 kDa. Isopropyl-beta-d-thiogalactopyranoside (IPTG) induction of E. coli M15 cells bearing the recombinant plasmid resulted in the extracellular production of active amylase. Western blot analysis also revealed that the truncated amylase was present in the periplasmic space and culture medium.

In this article, the author name Shih-Chin Cheng was incorrectly written as Shin-Chin Cheng.

Increased expression level of the Forkhead Box M1 (FOXM1) transcription factor is found in multiple types of cancers, and its expression is correlated with poor prognosis in patients with cancers, including non-small cell lung cancers and pancreatic cancers. We and others have shown that FoxM1 transcriptionally regulates a variety of genes essential for cell cycle progression, inflammation, angiogenesis, tumor cell invasiveness and survival. Published studies demonstrated that genetic deletion of Foxm1 gene from SPC-rtTA/tetO-KrasG12D/Foxm1 fl/fl mouse lung epithelial cells conferred resistance to tumorigenesis caused by oncogenic KrasG12D, indicating Foxm1 is a critical regulator of Kras signaling pathway during lung cancer initiation. When treated SPC-rtTA/tetO-KrasG12D/tetO-FOXM1 mice with Doxycycline, lung epithelial cell-specific expressed transgenic FOXM1 and Kras cooperate to promote tumor growth in mouse lungs. In the present study, we determine whether expression of FoxM1 affects proliferation of human cancer cells harboring oncogenic Kras. Here, we show that depletion of FOXM1 expression using inducible shFOXM1 diminished proliferation of Kras-mutated human non-small cell adenocarcinoma (A549 and NCI-H23) and pancreatic cancer (PANC-1 and AsPC-1) cell lines. In contrast, increased expression of FOXM1 caused increased proliferation of Kras mutated cancer cells. Scratch wound healing assay demonstrated that FOXM1 stimulates the migration of these cells, which is associated with elevated epithelial-mesenchymal transition (EMT) markers. Our studies demonstrate that FOXM1 transcription factor is required for Kras mutated human cancer cells proliferation during tumor progression. Citation Format: I-Ching Wang, Hsin Chih Chien, Sheng-Yang Chao, Chien-Cheng Li. Inhibition of Foxm1 transcription factor diminished Kras-mutated tumor development. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2015 Nov 5-9; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2015;14(12 Suppl 2):Abstract nr A44.