P53/MDM2 co-expression correlates with the tumour differentiation in oral squamous cell carcinoma – A retrospective study and a systematic review.
- Author:
Y.F. Choon
;
A. Ramanathan
;
H. Ali
;
W.M.N. Ghani
;
S.C. Cheong
;
R.B. Zain
- Publication Type:Journal Article
- From:
Annals of Dentistry
2011;18(1):8-17
- CountryMalaysia
- Language:English
-
Abstract:
Background: MDM2 and p53 are involved in a
negative feedback loop where p53 regulates MDM2 at
the transcriptional level. MDM2, in turn, downregulates
p53. This co-ordinated interaction between
these proteins is set to play an important role in the
regulation of cell cycle progression following DNA
damage to cells. The over-expression of both p53 and
MDM2 has been reported in various cancers. However
there are only few studies discussing the co-expression
of MDM2 with p53 in oral squamous cell carcinoma
Aim: The purpose of this study was to determine
the correlation of co-expression of p53, MDM2, and
Ki-67 proteins with clinico-pathological factors in oral
squamous cell carcinoma (OSCC) and to conduct a
systematic review of the co-expression of p53/MDM2.
Method: This is a retrospective descriptive study
and a systematic review. Formalin-fixed paraff inembedded
tissues from 45 OSCC cases were stained
by immunohistochemistry (IHC) for p53, MDM2, and
Ki-67 proteins.
Results: Immuno-reactivity for p53, MDM2, and
Ki-67 was seen in 75.6%, 97.8%, and 62.2% cases of
OSCC respectively. The co-expression of p53 and
MDM2 (p53/MDM2) was detected in 97.1%, however
there was no signif icant correlation between p53
and MDM2 expression. Notably, p53/MDM2 coexpression
was significantly associated with tumour
differentiation (p-value = 0.045). The Ki-67LI was not
signif icantly associated with neither MDM2 nor
p53/MDM2 co-expression (p-value = 0.268, 0.916
respectively).
Conclusion: The expression of MDM2 was not
signif icantly associated with p53 expression
suggesting that MDM2 expression is mediated by
p53-independent pathways or mutated p53 could not
induce the expression of MDM2 in this set of OSCCs.
The only clinico-pathological parameter that correlates
significantly with co-expression of p53/MDM2 is
tumour differentiation where it is suggestive that the
co-expression of these 2 proteins is indicative of
aggressive tumour behavior.
- Full text:W020150904554790595348.pdf
