Regulation of KRAS protein expression by miR-544a and KRAS-LCS6 polymorphism in wild-type KRAS sporadic colon adenocarcinoma

In this study, we investigated the KRAS status in correlation with clinicopathological features in sporadic CRC and more importantly the role oflet-7a-5p andmiR-544a-3p in the regulation of wild-type KRAS protein expression in the tumor center (T1) and invasive tumor front (T2). Analysis showed that 39.1% of tumor samples hadKRAS mutations. In wild-typeKRAS tumors, 62.0% were positive for KRAS protein expression and there was a higher percentage of KRAS-positive tumor cells and a higher intensity of immunohistochemical reaction in T2 than in T1 samples. This could not be attributed to differences inKRAS mRNA levels, suggesting regulation viamiR-544a-3p expression which was significantly decreased in T2 samples. Furthermore, we demonstrated that tumor samples carrying theKRAS-LCS6 variant allele had significantly higher protein expression of the wild-type KRAS. Our results suggest the role of theKRAS-LCS6 polymorphism andmiR-544a-3p expression in the regulation of wild-type KRAS protein expression in sporadic CRC.
Source: Human Cell - Category: Cytology Source Type: research