cell line
An immortalised cell line is a population of cells from a multicellular organism that would normally not proliferate indefinitely but, due to mutation, have evaded normal cellular senescence and instead can keep undergoing division. The cells ...
(epidermoid carcinoma) used in
biomedical research
Medical research (or biomedical research), also known as health research, refers to the process of using scientific methods with the aim to produce knowledge about human diseases, the prevention and treatment of illness, and the promotion of ...
.
Characteristics
A431 cells were established from an
epidermoid carcinoma
Squamous-cell carcinoma (SCC), also known as epidermoid carcinoma, comprises a number of different types of cancer that begin in squamous cells. These cells form on the surface of the skin, on the lining of hollow organs in the body, and on the l ...
in the skin (
epidermis
The epidermis is the outermost of the three layers that comprise the skin, the inner layers being the dermis and Subcutaneous tissue, hypodermis. The epidermal layer provides a barrier to infection from environmental pathogens and regulates the ...
tyrosine
-Tyrosine or tyrosine (symbol Tyr or Y) or 4-hydroxyphenylalanine is one of the 20 standard amino acids that are used by cells to synthesize proteins. It is a conditionally essential amino acid with a polar side group. The word "tyrosine" is ...
phosphorylation
In biochemistry, phosphorylation is described as the "transfer of a phosphate group" from a donor to an acceptor. A common phosphorylating agent (phosphate donor) is ATP and a common family of acceptor are alcohols:
:
This equation can be writ ...
of
intracellular
This glossary of biology terms is a list of definitions of fundamental terms and concepts used in biology, the study of life and of living organisms. It is intended as introductory material for novices; for more specific and technical definitions ...
signaling
protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residue (biochemistry), residues. Proteins perform a vast array of functions within organisms, including Enzyme catalysis, catalysing metab ...
s which control cellular processes such as growth, proliferation and
apoptosis
Apoptosis (from ) is a form of programmed cell death that occurs in multicellular organisms and in some eukaryotic, single-celled microorganisms such as yeast. Biochemistry, Biochemical events lead to characteristic cell changes (Morphology (biol ...
. At low (picomolar) concentrations, EGF promotes cell growth of A431 cells whereas at higher (nanomolar) concentrations it inhibits growth by causing the cells to terminally differentiate. Treatment of A431 cells with
bradykinin
Bradykinin (BK) (from Greek ''brady-'' 'slow' + ''-kinin'', ''kīn(eîn)'' 'to move') is a peptide that promotes inflammation. It causes arterioles to dilate (enlarge) via the release of prostacyclin, nitric oxide, and endothelium-derived hyperpo ...
reduces basal and EGF-induced EGFR phosphorylation. Treatment with
Sertoli cell
Sertoli cells are a type of sustentacular "nurse" cell found in human testes which contribute to the process of spermatogenesis (the production of sperm) as a structural component of the seminiferous tubules. They are activated by follicle-sti ...
secreted growth factor (SCSGF) strongly induces cell proliferation. Stimulation of A431 cells with
phorbol esters
Phorbol esters are a class of chemical compounds found in a variety of plants, particularly in the families Euphorbiaceae and Thymelaeaceae. Chemically, they are ester derivatives of the tetracyclic diterpenoid phorbol.
Biological activity
Prote ...
induces expression of
interleukin 1
The Interleukin-1 family (IL-1 family) is a group of 11 cytokines that plays a central role in the regulation of immune and inflammatory responses to infections or sterile insults.
Discovery
Discovery of these cytokines began with studies on t ...
cell cycle
The cell cycle, or cell-division cycle, is the sequential series of events that take place in a cell (biology), cell that causes it to divide into two daughter cells. These events include the growth of the cell, duplication of its DNA (DNA re ...
and
cancer
Cancer is a group of diseases involving Cell growth#Disorders, abnormal cell growth with the potential to Invasion (cancer), invade or Metastasis, spread to other parts of the body. These contrast with benign tumors, which do not spread. Po ...
-associated
cell signalling
In biology, cell signaling (cell signalling in British English) is the process by which a cell interacts with itself, other cells, and the environment. Cell signaling is a fundamental property of all cellular life in both prokaryotes and eukary ...
pathways since they
express
Express, The Expresss or EXPRESS may refer to:
Arts, entertainment and media Film
* ''Express: Aisle to Glory'', a 1998 comedy short film featuring Kal Penn
* ''The Express: The Ernie Davis Story'', a 2008 film starring Dennis Quaid
* The Expre ...
control
Control may refer to:
Basic meanings Economics and business
* Control (management), an element of management
* Control, an element of management accounting
* Comptroller (or controller), a senior financial officer in an organization
* Controlling ...
for EGFR
expression
Expression may refer to:
Linguistics
* Expression (linguistics), a word, phrase, or sentence
* Expression (mathematics), Symbolic description of a mathematical object
* Fixed expression, a form of words with a specific meaning
* Idiom, a type of ...
. They contain no functional
p53
p53, also known as tumor protein p53, cellular tumor antigen p53 (UniProt name), or transformation-related protein 53 (TRP53) is a regulatory transcription factor protein that is often mutated in human cancers. The p53 proteins (originally thou ...
, a potent
tumor suppressor gene
A tumor suppressor gene (TSG), or anti-oncogene, is a gene that regulates a cell (biology), cell during cell division and replication. If the cell grows uncontrollably, it will result in cancer. When a tumor suppressor gene is mutated, it results ...
, and are highly sensitive to
mitogen
A mitogen is a small bioactive protein or peptide that induces a cell to begin cell division, or enhances the rate of division (mitosis). Mitogenesis is the induction (triggering) of mitosis, typically via a mitogen.
The cell cycle
Mitogens a ...
ic stimuli. In
xenograft
Xenotransplantation (''xenos-'' from the Greek meaning "foreign" or strange), or heterologous transplant, is the transplantation of living cells, tissues or organs from one species to another.radiation sensitization characteristics. Other ''
in vitro
''In vitro'' (meaning ''in glass'', or ''in the glass'') Research, studies are performed with Cell (biology), cells or biological molecules outside their normal biological context. Colloquially called "test-tube experiments", these studies in ...
'' studies have found EGF to also cause substantial lowering of
DNA replication
In molecular biology, DNA replication is the biological process of producing two identical replicas of DNA from one original DNA molecule. DNA replication occurs in all life, living organisms, acting as the most essential part of heredity, biolog ...
and protein synthesis. The A431 lines engineered to express tumor antigens such as
mesothelin
Mesothelin, also known as MSLN, is a protein that in humans is encoded by the ''MSLN'' gene.
Function
Mesothelin is a 40 kDa protein that is expressed in mesothelial cells. The protein was first identified by its reactivity with monoclonal an ...
and
GPC3
Glypican-3 is a protein that, in humans, is encoded by the ''GPC3'' gene. The ''GPC3'' gene is located on human X chromosome (Xq26) where the most common gene (Isoform 2, GenBank Accession No.: NP_004475) encodes a 70-kDa core protein with 580 am ...
have been made as cell models to test cancer therapeutics.