Immunohistochemical study of p53 and proliferating cell nuclear antigen expression in odontogenic keratocyst and periapical cyst

The effects of proliferating cell nuclear antigen and p53 in patients with oral squamous cell carcinoma: a systematic review and meta-analysis

BACKGROUND

To evaluate the effect of proliferating cell nuclear antigen (PCNA) and p53 in patients with oral squamous cell carcinoma (OSCC).

METHODS

Multiple databases, including PubMed, Embase, Cochrane library, and China National Knowledge Database, were searched for relevant studies and full-text articles that evaluated the effect of PCNA and p53 in patients with OSCC. Review Manager 5.2 was adopted to estimate the impact of the results among the selected articles. Forest plots, NOS table, sensitivity analysis, and bias analysis were also conducted.

RESULTS

In total, nine eligible studies satisfied the included criteria. High PCNA expression (>50%) was significantly more prevalent in OSCC than low PCNA expression (<50%) (OR =3.88; 95% CI: 2.04-7.37; P<0.0001; I²=0%). However, there was no significant difference between p53 and OSCC (OR =1.60; 95% CI: 0.18-14.63; P=0.68; I²=86%). Low PCNA expression had a higher 5-year overall survival in OSCC patients than high PCNA expression (OR =0.47; 95% CI: 0.27-0.80; P=0.005; I²=41%). Meanwhile, p53 negative had a higher 5-year overall survival than p53 positive (OR =0.20; 95% CI: 0.10-0.42; P<0.0001; I²=0%). There was no difference between high and low PCNA in terms of metastasis (OR =0.80 with 95% CI: 0.18-3.45, I²=63%, P of over effect =0.76). The overall results showed no difference between p53 and metastasis (OR =0.38 with 95% CI: 0.13-1.10, I²=0%, P of over effect =0.07).

DISCUSSION

PCNA and p53 might be suitable for prognostic and survival evaluation in OSCC patients.

Genetic factors in the pathogenesis of ameloblastoma, dentigerous cyst and odontogenic keratocyst

Ameloblastoma (AB), dentigerous cyst (DC) and Odontogenic keratocyst (OKC) are odontogenic lesions with propensity to malignant transformation or local invasion. The molecular mechanisms of development of these lesions are not fully understood. However, some researches have reported dysregulation of tumor suppressor genes or oncogenes in these lesions. Down-regulation of P53 gene has been reported in AB, DC and OKC. Moreover, several long non-coding RNAs such as ENST00000512916 and KIAA0125 have been dysregulated in AB tissues. Single nucleotide polymorphisms within a variety of genes have been associated with certain types of odontogenic lesions. In the current review, we summarize the current data about the expression pattern of genes in these lesions and the observed association between genetic polymorphisms and development of these lesions.

Protein 53, B-Cell Lymphoma-2, Cyclooxygenase-2, and CD105 Reactivity in Keratocystic Odontogenic Tumors: An Immunohistochemical Analysis

OBJECTIVE

The objective is to evaluate and compare immunohistochemically, the biological behavior of keratocystic odontogenic tumor (KCOT) with normal oral mucosa by analyzing cell proliferation, angiogenesis, and antiapoptosis using cyclooxygenase-2 (COX-2), protein 53 (p53), B-cell lymphoma-2 (Bcl-2), and CD105 (endoglin).

MATERIALS AND METHODS

The present study comprised 30 cases of KCOT in the study group, in which the expression of COX-2, p53, Bcl-2, and CD105 were analyzed and compared with that of control group consisting of 30 normal oral mucosae.

RESULTS

The results were evaluated based on a number of positively stained cells; among 30 samples of KCOT, 22 samples were p53 positive, 23 samples were Bcl-2 positive, 18 samples were COX-2 positive, whereas all the above markers were negative in all the 30 samples of the normal oral mucosa and CD105 mean vascular density in KCOT 13.8 in normal oral mucosa.

CONCLUSION

The present study suggests that angiogenesis, cell proliferation, and antiapoptosis may be the possible factors contributing for the unique biological behavior of KCOT.

Apoptosis and cell cycle aberrations in epithelial odontogenic lesions: An evidence by the expression of p53, Bcl-2 and Bax

Background

Ameloblastoma (AMB), odontogenic keratocyst (OKC) and adenomatoid odontogenic tumor (AOT) are epithelial odontogenic lesions with diverse biologic profiles. Defects in regulation of apoptosis and cell cycle may be involved in the development and progression of those lesions, therefore we aimed to investigate the expression of Bcl-2, Bax and p53 to better understand the possible role of these proteins in AMBs, OKCs and AOTs.

Material and Methods

The studied sample consisted of 20 AMBs, 20 OKCs and 20 AOTs. Immunohistochemistry technique was performed for the antibodies p53, Bcl-2 and Bax. Immunoreactivity was observed in the epithelial component and positive cells were counted in five fields (100x magnification). Statistical analysis was performed with Kruskal-Wallis and Spearman tests (p<0.05).

Results

All lesions exhibited staining for the three studied proteins. There was no statistically significant associations between the expression of proteins and the lesions, however we identified a positive correlation between the expression of p53 and Bcl-2 (r = 0.200) and a negative correlation between p53 and Bax expressions (r = -0.100). In addition, p53 and Bax were similarly expressed between AMBs and OKCs. Bcl-2 was similarly expressed in AMBs and AOTs.

Conclusions

Apoptosis regulatory proteins, as well as cell cycle proteins, are differently expressed in epithelial odontogenic lesions and their expression is possibly related to the biological behavior of AMB, OKC and AOT.

Key words:Odontogenic tumors, apoptosis, apoptosis regulatory proteins, p53 tumor suppressor protein, immunohistochemistry.

Clinical significance of expression of proliferating cell nuclear antigen and E-cadherin in gastric carcinoma

AIM

to investigate the expression of proliferating cell nuclear antigen (PCNA) and E-cadherin in gastric carcinoma and to analyze their clinical significance.

METHODS

A total of 146 patients were selected for this study, including 38 patients with intestinal metaplasia, 42 with dysplasia, and 66 with primary gastric cancer. In addition, 40 patients with normal gastric tissues were selected as controls. The expression of PCNA and E-cadherin was detected by immunohistochemistry. Differences in PCNA and the E-cadherin labeling indexes among normal gastric mucosa, intestinal metaplasia, dysplasia, and gastric carcinoma were compared. Subjects with normal gastric tissues were assigned to a normal group, while gastric cancer patients were assigned to a gastric cancer group. The difference in PCNA and E-cadherin expression between these two groups was compared. The relationship between expression of PCNA and E-cadherin and clinicopathological features was also explored in gastric cancer patients. Furthermore, prognosis-related factors, as well as the expression of PCNA and E-cadherin, were analyzed in patients with gastric cancer to determine the 3-year survival of these patients.

RESULTS

The difference in PCNA and the E-cadherin labeling indexes among normal gastric mucosa, intestinal metaplasia, dysplasia, and gastric carcinoma was statistically significant (P < 0.05). During the transition of normal gastric mucosa to gastric cancer, the PCNA labeling index gradually increased, while the E-cadherin labeling index gradually decreased (P < 0.05). The PCNA labeling index was significantly higher and the E-cadherin labeling index was significantly lower in gastric cancer than in dysplasia (P < 0.05). The expression of PCNA was significantly higher in the gastric cancer group than in the normal group, but E-cadherin was weaker (P < 0.05). There was a negative correlation between the expression of PCNA and E-cadherin in gastric carcinoma (r = -0.741, P = 0.000). PCNA expression differed significantly between gastric cancer patients with and without lymph node metastasis and between patients at different T stages. E-cadherin expression also differed significantly between gastric cancer patients with and without lymph node metastasis (P < 0.05). High T stage and positive PCNA expression were risk factors for the prognosis of patients with gastric cancer (RR > 1), while the positive expression of E-cadherin was a protective factor (RR < 1). The sensitivity, specificity, and accuracy of PCNA positivity in predicting the 3-year survival of patients with gastric cancer were 93.33%, 38.89%, and 0.64, respectively; while these values for E-cadherin negativity were 80.0%, 41.67%, and 0.59, respectively. When PCNA positivity and E-cadherin negativity were combined, the sensitivity, specificity, and accuracy were 66.67%, 66.67%, and 0.67, respectively.

CONCLUSION

Combined detection of PCNA and E-cadherin can improve the accuracy of assessing the prognosis of patients with gastric cancer.