p53 expression in oral precancer as a marker for malignant potential.
The potential of p53 protein expression as a marker for determining which oral precancerous lesions may transform to malignancy with time was assessed. We compared the p53 expression in archival formalin-fixed, paraffin-embedded tissues from 22 baseline biopsies of precancerous lesions that transformed to cancer in 4-25 years against that in 68 similar lesions that did not transform over the same time period. Twenty-nine percent of precancers that transformed were p53-positive at baseline, compared to 31% of the biopsies that did not transform to malignancy. When examined by immunohistochemical methods p53 expression failed to detect potential malignant status of oral precancer. Non-specificity of the assay may account for this result but overexpression of p53 due to DNA damage by tobacco/betel-quid in non-progressive lesions needs further study. Nine precancerous lesions became p53-immunoreactive from precancer to cancer. This may suggest p53 overexpression peaks close to the time of transition from precancer to cancer rather than early in the natural history of oral precancer.
Basic Dental Research Unit and WHO Collaborating Centre for Oral Cancer Prevention, Tata Institute of Fundamental Research, Bombay, India.
P R
PR
Murti
K A
KA
Warnakulasuriya
N W
NW
Johnson
R B
RB
Bhonsle
P C
PC
Gupta
D K
DK
Daftary
F S
FS
Mehta
D001114:Areca; D014408:Biomarkers, Tumor / Q000235:genetics*; D001706:Biopsy; D002471:Cell Transformation, Neoplastic / Q000235:genetics* / Q000473:pathology; D004249:DNA Damage; D005404:Fixatives; D005500:Follow-Up Studies; D005557:Formaldehyde; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007150:Immunohistochemistry; D007972:Leukoplakia, Oral / Q000235:genetics / Q000473:pathology; D009062:Mouth Neoplasms / Q000235:genetics* / Q000473:pathology; D016612:Paraffin Embedding; D010946:Plants, Medicinal; D010947:Plants, Toxic; D011230:Precancerous Conditions / Q000235:genetics* / Q000473:pathology; D014030:Tobacco, Smokeless; D016159:Tumor Suppressor Protein p53 / Q000032:analysis / Q000235:genetics*
D014408:Biomarkers, Tumor; D005404:Fixatives; D016159:Tumor Suppressor Protein p53; D005557:Formaldehyde