Exome sequencing of oral leukoplakia and oral squamous cell carcinoma implicates DNA damage repair gene defects in malignant transformation

Background: As most of the oral squamous cell carcinoma develop from precursor premalignant lesions, it would be helpful if the malignant transformation is detected early in premalignant state. The objective of the research was to study the role of immunohistochemical expression of p53 and Ki-67 in oral premalignant lesion and squamous cell carcinoma.Materials and Methods: The expression of immunomarkers p53 and Ki67 were studied on formalin fixed paraffin embedded tissue sections from human oral squamous mucosal lesion for duration of 1 year. Results: Of total 36 cases, 80% cases of keratosis without dysplasia showed basal pattern of p53 staining while 47.1% cases of squamous cell carcinoma showed p53 staining in all layers of epithelium. The median p53 Labelling Index of squamous cell carcinoma was more than those of keratosis with and without dysplasia though the result was statistically non-significant. 50.0% cases of keratosis without dysplasia and 83.3% cases of keratosis with dysplasia displayed Ki-67 immunostaining confined to basal and suprabasal layer whereas 94.1% cases of squamous cell carcinoma showed Ki-67 positivity in all layers of epithelium. Median Ki-67 Labelling Index increased from keratosis without dysplasia to keratosis with dysplasia to squamous cell carcinoma, difference being statistically significant. A positive and insignificant correlation was observed between p53 and Ki-67 Labelling Index.Conclusion: Increased expressions of Ki-67 and p53 in oral squamous cell carcinoma compared to premalignant lesion suggest that they may be useful indicator of malignant transformation in dysplastic lesion.

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Palbociclib induces DNA damage and inhibits DNA repair to induce cellular senescence and apoptosis in oral squamous cell carcinoma

Journal of the Formosan Medical Association ◽

10.1016/j.jfma.2020.12.009 ◽

2020 ◽

Author(s):

Tong-Hong Wang ◽

Chin-Chuan Chen ◽

Yann-Lii Leu ◽

Yun-Shien Lee ◽

Jang-Hau Lian ◽

...

Keyword(s):

Dna Damage ◽

Squamous Cell Carcinoma ◽

Dna Repair ◽

Oral Squamous Cell Carcinoma ◽

Cell Carcinoma ◽

Squamous Cell ◽

Cellular Senescence

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Expression of MMR system genes is correlated to NF-kB in patients with oral squamous cell carcinoma

Journal of Clinical Pathology ◽

10.1136/jclinpath-2019-206161 ◽

2019 ◽

Vol 73 (5) ◽

pp. 273-277

Author(s):

Alexandre Fonseca ◽

Matheus Perez ◽

Glaucia Veiga ◽

Fábio Prosdócimi ◽

Fabio Nunes ◽

...

Keyword(s):

Squamous Cell Carcinoma ◽

Oral Squamous Cell Carcinoma ◽

Cell Carcinoma ◽

Squamous Cell ◽

Control Group ◽

Mismatch Repair Gene ◽

Strong Indication ◽

Repair Gene ◽

Repair Genes ◽

Base Of The Tongue

AimsThe aim of this study was to evaluate the mismatch repair gene expression and their correlation with NF-kB in patients with oral squamous cell carcinoma (SCC).MethodsTotal RNA was isolated from 28 biopsy samples. A control group was composed of 20 volunteers. Differential expression of hMSH2, hMSH6 and NF-kB genes was accessed by quantitative PCR.ResultsThere is increased expression of all the analysed genes when the patients were smokers and alcoholics. In addition, there is increased expression of hMSH2 when SCC was removed from the base of the tongue. There was a correlation between NF-kB and hMSH2 and hMSH6 as well as between repair genes hMSH2 and hMSH6 expression levels. There is increased expression of the hMSH2 gene in patients with SCC, especially in the alcoholics.ConclusionsThere is a strong indication that NF-kB gene was expressed along with the studied repair genes, evidencing the possibility that this system can be activated by the inflammatory pathway.

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