Human Epithelial Cells: Barriers to the External Environment
Epithelial cells cover the external surface of the body and line internal organs. They are categorized into three types: squamous, columnar, and cuboidal. A single layer of epithelial cells is defined as a simple epithelium, while two or more layers of epithelial cells is defined as stratified epithelium. Epithelial cells are supported by an underlying basement membrane and contact each other through protein complexes known as tight junctions.
Epithelial cells are found throughout the body, including the gastrointestinal tract, the skin, and the airway. Epithelial cells in the gastrointestinal tract perform digestive and absorptive functions, while protecting the organ from ingested pathogens. On the external surface of the body, epithelial cells of the skin protect the entire body from the external environment. In particular, the respiratory epithelium serves a protective function, providing a barrier between the internalized air and the internal milieu. The respiratory epithelium also secretes mucous, which coats the airways, providing additional protection against pathogens that might enter the airways.
The Latest Research Using Lifeline® Epithelial Cells
Lung cancer is the deadliest human cancer, killing approximately 158,000 people in 2015. Targeted therapies against the receptor tyrosine kinase (RTK), epidermal growth factor receptor (EGFR), provide some clinical benefit, but patients often develop resistance to EGFR inhibitors, through secondary EGFR mutations or amplification of MET, another RTK. In their 2013 study, Byun et al. set out to discover whether USP8, a deubiquitinating protein, could be a therapeutic target in non-small cell lung cancer (NSCLC). They found that USP8 knockdown or inhibition decreased viability and proliferation of NSCLC cells. They determined that USP8 inhibition increased the EGFR association with ubiquitin and decreased EGFR total levels. Finally, the researchers demonstrated that a USP8 inhibitor decreased NSCLC xenograft tumor growth. They used Lifeline® human bronchial/tracheal epithelial cells as normal controls and found that USP8 knockdown or inhibition had no effect on cell viability, illustrating that this therapeutic option is selective for cancer cells only. Altogether, their study suggests that USP8 may indeed be a therapeutic target in both EGFR inhibitor-resistant and -sensitive NSCLC.
Lifeline® offers multiple epithelial cell types and associated culture media:
- Airway epithelial cells and BronchiaLife Medium
- Bladder epithelial cells and UroLife Medium
- Corneal epithelial cells and OcuLife Medium
- Keratinocytes and DermaLife Medium
- Mammary epithelial cells and MammaryLife Medium
- Prostate epithelial cells and ProstaLife Medium
- Renal epithelial cells and RenaLife Medium
- Seminal Vesicle epithelial cells and ProstaLife Medium
For studies using other Lifeline® epithelial cell types that have been discussed in previous blog posts, see the following studies:
Prostate Epithelial Cells:
The ETS domain transcription factor ELK1 directs a critical component of growth signaling by the androgen receptor in prostate cancer cells. http://www.ncbi.nlm.nih.gov/pubmed/23426362
Bladder Epithelial Cells:
CLT1 targets bladder cancer through Integrin a5b1 and CLIC3. http://www.ncbi.nlm.nih.gov/pubmed/23204394
Renal Epithelial Cells:
Englerin A selectively induces necrosis in human renal cancer cells. http://www.ncbi.nlm.nih.gov/pubmed/23144724
Mammary Epithelial Cells:
Blocking the formation of radiation-induced breast cancer stem cells. http://www.ncbi.nlm.nih.gov/pubmed/25003837
Tell us how you are using our epithelial cells and your study could be featured here on our blog!