Human Lung Epithelial Cells Progressed to Malignancy through Specific Oncogenic Manipulations

Abstract

We used CDK4/hTERT-immortalized normal human bronchial epithelial cells (HBECs) from several individuals to study lung cancer pathogenesis by introducing combinations of common lung cancer oncogenic changes (p53, KRAS, MYC) and followed the stepwise transformation of HBECs to full malignancy. This model demonstrated that: 1) the combination of five genetic alterations (CDK4, hTERT, sh-p53, KRASV12, and c-MYC) is sufficient for full tumorigenic conversion of HBECs; 2) genetically-identical clones of transformed HBECs exhibit pronounced differences in tumor growth, histology, and differentiation; 3) HBECs from different individuals vary in their sensitivity to transformation by these oncogenic manipulations; 4) high levels of KRASV12 are required for full malignant transformation of HBECs, however prior loss of p53 function is required to prevent oncogene-induced senescence; 5) over-expression of c-MYC greatly enhances malignancy but only in the context of sh-p53+KRASV12; 6) growth of parental HBECs in serum-containing medium induces differentiation while growth of oncogenically manipulated HBECs in serum increases in vivo tumorigenicity, decreases tumor latency, produces more undifferentiated tumors, and induces epithelial-to-mesenchymal transition (EMT); 7) oncogenic transformation of HBECs leads to increased sensitivity to standard chemotherapy doublets; 8) an mRNA signature derived by comparing tumorigenic vs. non-tumorigenic clones was predictive of outcome in lung cancer patients. Collectively, our findings demonstrate this HBEC model system can be used to study the effect of oncogenic mutations, their expression levels, and serum-derived environmental effects in malignant transformation, while also providing clinically translatable applications such as development of prognostic signatures and drug response phenotypes.

Small cell lung cancer tumors and preclinical models display heterogeneity of neuroendocrine phenotypes

“…These cell lines will be described in detail elsewhere, and will not be discussed further in this report. Non-malignant tissues and immortalized respiratory epithelial cells (29) had negative scores. The signature is cross platform, with a very high concordance (98%) between RNASeq and microarray expression data and can also be applied to murine in vitro systems (GEM models and cell lines).…”

Immunological metagene signatures derived from immunogenic cancer cell death associate with improved survival of patients with lung, breast or ovarian malignancies: A large-scale meta-analysis

“…first a MAS5 algorithm-based normalization on individual-chip level and a second scaling normalization to set the average expression on each chip to 1,000. 39 For the 'validation dataset' analysis, the cohorts consisting of >250 patients each for breast cancer (n D 285; GSE2034), 53 non-small cell lung cancer (n D 274; GSE41271) 54,55 and ovarian cancer (n D 259; GSE32062) 56 were analyzed as described above, using the PROGgeneV2 platform. 57 The available clinicopathological characteristics of the patients in these respective 'validation' cohorts are described in Table S2.…”

Lack of epithelial-to-mesenchymal transition induction in two bronchial epithelial cell lines after alpha and gamma irradiation

“…The SV40 large T-antigen has been linked to cell immortalisation by its binding to tumour suppressor proteins Rb and p53 which may inhibit important regulatory pathways thus making the cells susceptible to tumourigenesis (Cheng et al, 2009). Part of that process is that the cells may become more prone to TGF-β-induced EMT (Sato et al, 2013). Although some studies report that the BEAS-2B cell line is non-tumourigenic in nude mice, conditioned media from the same cell line had the ability to change the growth characteristics and induce increased differentiation of normal bronchial epithelial cells.…”

“…The authors hypothesised that the effect is due to TGF-β production from the BEAS-2B cells (Albright et al, 1990). On the other hand, the HBEC-3KT cells that have functional p53, are still able to express contact inhibition and are non-tumourigenic in laboratory animals (Sato et al, 2013). The HBEC-3KT cells could be regarded as more close to normal epithelial cell model, while the BEAS-2B cells have some characteristics of tumourigenic cells.…”