Immunohistochemical evaluation of Ki-67, PCNA and MCM2 proteins proliferation index (PI) in advanced gastric cancer.

Abstract

Abstract:The current study objective was to assess the proliferation indices (PI) of Ki-67, PCNA and MCM2 proteins in advanced gastric cancer and in metastatic lymph node in correlation with certain clinicopathological features and with postoperative survival of patients. The study was conducted in a group of 100 patients with advanced gastric cancers. Involvement of local lymph nodes was present in 36 cases. Immunohistochemical investigations were carried out using monoclonal antibodies against Ki-67 (DAKO), PCNA (DAKO) and polyclonal antibody to MCM2 (Santa Cruz Biotechnology). Visualization of the antigen/antibody complex was performed using LSAB technique (biotin-streptavidin-peroxidase) followed by application of chromogene DAB (DAKO). Statistical analysis revealed no correlations of Ki-67, PCNA and MCM2 PI in tumour tissue or metastatic lymph node with patients' age and gender, tumour location, histological grade, macroscopic type according to Bormann's classification and histological grading by Lauren's and Goseki's classifications. Moreover, no correlation was observed of Ki-67 and MCM2 PI in tumour tissue with histological grading. No correlation was also noted between the proliferation indices of all the three proteins in the affected lymph node and grade of histological differentiation. Such clinicopathological parameters as patients' age and gender, histological grading by Lauren's and Goseki's classifications and lymph node involvement did not correlate with survival time of patients. Furthermore, no statistically significant correlation was shown of postoperative survival time with Ki-67 and MCM2 PI in tumour tissue and metastatic lymph nodes and with PCNA PI in the affected lymph nodes. However, a statistically significant correlation was found of Ki-67, PCNA and MCM2 PI in tumour tissue and metastatic lymph nodes with depth of wall invasion and local lymph node involvement. A statistically significant correlation was also noted between PCNA PI in the main mass of tumour and histological grading. The postoperative survival time of patients exhibited a statistically significant correlation with tumour location and macroscopic type according to Bormann's classification. Correlations on statistical borderline were noted between survival time and depth of gastric wall invasion and PCNA PI in the main mass of tumour.

Correlation of Ki-67 and MCM-2 proliferative marker expression with grade of histological malignancy (G) in ductal breast cancers.

“…Ki-67 and MCM-2 were also evaluated in advanced gastric cancer. Although this study did not show any correlation between both markers, shorter postoperative survival time was associated with high MCM-2 expression [33].…”

“…Expression of the proteins was studied in cancers of the larynx, oral cavity, thyroid gland, in tumours of salivary gland, colorectal cancers, tumours of adrenal glands, lungs and in renal carcinoma [22][23][24][25][26][27][28][29][30][31]33]. Results of some investigators suggested a higher prognostic value of MCM-2 protein than that manifested by currently widely used Ki-67 [23,28,30,34,35].…”

Protein Signatures for Classification and Prognosis of Gastric Cancer

“…Czyzewska et al 23 reported a statistically significant correlation of PCNA in advanced gastric cancer with local lymph node involvement. Katarzyna et al reported that the expression of PCNA was found to correlate with the presence of lymph node metastases in colon cancer.…”

Overexpression of minichromosome maintenance 2 predicts poor prognosis in patients with gastric cancer

“…Czyzewska et al (27) assessed the proliferation indices (PI) of Ki-67, PCNA and MCM2 proteins in advanced gastric cancer and in metastatic lymph nodes and the correlation of these markers with certain clinicopathological features; they concluded that Ki-67, PCNA and MCM2 PI in tumor tissue and metastatic lymph nodes were significantly correlated with the depth of wall invasion and local lymph node involvement. In our study, we revealed a significant correlation between elevated MCM2 expression and patient age (P=0.026), T category (P=0.002) and the presence of lymph node metastasis (P=0.044).…”