Tumor promotion is a process in
carcinogenesis by which various factors permit the descendants of a single
initiated cell to survive and expand in number, i.e. to resist
apoptosis
Apoptosis (from grc, ἀπόπτωσις, apóptōsis, 'falling off') is a form of programmed cell death that occurs in multicellular organisms. Biochemical events lead to characteristic cell changes (morphology) and death. These changes incl ...
and to undergo
clonal growth. This is a step toward
tumor progression.
In order for a tumor cell to survive, it must decrease its expression of
tumor suppressor genes such as
p53,
BRCA1,
BRCA2
''BRCA2'' and BRCA2 () are a human gene and its protein product, respectively. The official symbol (BRCA2, italic for the gene, nonitalic for the protein) and the official name (originally breast cancer 2; currently BRCA2, DNA repair associated) ...
,
RB1, or the
fas receptor. A tumor suppressor would trigger an apoptotic pathway in a cancer cell if there were DNA damage, polyploidy, or uncontrolled cell growth.
Simultaneously, tumor cells need to upregulate
oncogenes, which promote or cause downstream activation of growth factors and cell survival signals such as RAS,
Mitogen-activated protein kinase kinase,
VEGF, or
Akt.
See also
*
Phorbol myristate acetate
12-''O''-Tetradecanoylphorbol-13-acetate (TPA), also commonly known as tetradecanoylphorbol acetate, tetradecanoyl phorbol acetate, and phorbol 12-myristate 13-acetate (PMA) is a diester of phorbol. It is a potent Tumor promotion, tumor promoter ...
*
Tumor initiation
*
Tumor progression
References
Carcinogenesis
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