Features of genes copy number in normal, primary tumor, and lymph nodes metastases cells in patients with cervical cancer.

Abstract

e17503 Background: Early stages of cervical cancer (CC) can be treated with surgery or radiation therapy, metastatic CC is incurable, and therefore new diagnostic approaches based on highly effective molecular markers are required. As such markers, the Copy Number Variation (CNV) is of great interest. Purpose of the study: to analyze the peculiarities of genes CNV in normal cells, primary tumor and lymph nodes tumor metastases cells in patients with CC. Methods: Tissue sections from FFPE-blocks of 300 patients with CC were used for the study. Primary tumor, tumor metastatic and normal cells were isolated using non-contact laser microdissection (Palm MicroBeam, Carl Zeiss). DNA was extracted from the cells using the phenol-chloroform method. Determination of 14 genes CNV (LAMP3, PRKAA1, TORC2, FOXO3, HDAC5, MEF2C, MLXIPL, EP300, HNF4A, TP53, SREBF1, SREBF2, PPARGC1A, and CCND1) was performed by Real-Time qPCR method. Statistical analysis was performed using the Mann-Whitney test; Bonferroni's correction was applied to correct multiple comparisons. Results: An increase in the CNV of LAMP3 and TORC2 genes by 2.5 and 3.2 times (p < 0.05), respectively, and a decrease in the CNV of TP53 and FOXO3 genes by 2.3 and 2.0 times (p < 0.05), respectively, were found in the primary tumor cells relative to normal cells. The effect of the simultaneous change in the CNV of LAMP3, TORC2, TP53 and FOXO3 genes was observed in 60% of the sample, and LAMP3 and TP53 genes - in 80%. In cells of lymph nodes tumor metastases an increase in the CNV of CCND1 and TORC2 genes by 2.0 and 3.5 times (p < 0.05), respectively, was found, as well as a decrease in the CNV of PPARGC1A gene by 2.1 times (p < 0.05) relative to normal cells. A simultaneous change in the CNV of CCND1, TORC2, and PPARGC1A was observed in 70% of the sample, and CNV of CCND1 and TORC2 genes - in 85%. Primary tumor and metastases cells differed in the CNV of CCND1 (2.5 times higher in metastatic cells), LAMP3 (3.0 times lower in metastatic cells) and FOXO3 genes (2.0 times higher in metastatic cells). Conclusions: Thus, the primary tumor and lymph nodes metastases cells differ in the level of genes CNV from normal cervix cells. Accordingly, the CNV of LAMP3, TORC2, TP53 and FOXO3 genes may have the potential for diagnosing a primary cervical tumor, and the CNV of CCND1, TORC2 and PPARGC1A genes for diagnosing its metastases to regional lymph nodes.