Abstract
This study investigated whether alterations in the expression of genes integral to the c-Jun N-terminal kinase (JNK) signaling pathway play a role in the pathogenesis of colorectal cancer (CRC). It analyzed the expression of genes encoding two JNK isoforms (MAPK8 and MAPK9) and the JNK-activating kinases (MAP2K4 and MAP2K7). Gene expression patterns in CRC tissue were compared with existing data in public online databases to provide an integrated understanding of their potential role in tumorigenesis. The material consisted of 55 cancer tissue fragments collected intraoperatively from patients with histopathologically confirmed CRC. Total RNA isolated from these tissues was used to determine the relative expression of the selected genes using quantitative PCR. Additionally, data from publicly accessible bioinformatics databases were utilized. MAP2K7 gene expression was significantly elevated in tumor specimens with higher histological grades. Conversely, MAPK9 gene expression tended to be higher in tumor tissues with lower histological grades. Moreover, elevated MAPK8 gene expression was linked to an increased incidence of regional lymph node metastasis. Furthermore, bioinformatics analysis confirmed that MAP2K7 and MAPK8 appear to promote tumor aggressiveness and metastasis, whereas MAPK9 and MAP2K4 may have a protective or regulatory role in early stages of the disease.