Milena Pązik1, Katarzyna Michalska2, Marta Żebrowska-Nawrocka2, Izabela Zawadzka2, Mariusz Łochowski3, Ewa Balcerczak2. 1. Laboratory of Molecular Diagnostics and Pharmacogenomics, Department of Pharmaceutical Biochemistry and Molecular Diagnostics, Cathedral of Laboratory and Molecular Diagnostics, Medical University of Lodz, Muszynskiego 1, 90-151, Lodz, Poland. milena.pazik@umed.lodz.pl. 2. Laboratory of Molecular Diagnostics and Pharmacogenomics, Department of Pharmaceutical Biochemistry and Molecular Diagnostics, Cathedral of Laboratory and Molecular Diagnostics, Medical University of Lodz, Muszynskiego 1, 90-151, Lodz, Poland. 3. Department of Thoracic Surgery, Memorial Copernicus Hospital, Medical University of Lodz, Lodz, Poland.
Abstract
BACKGROUND: The RAS family protooncogenes, including KRAS, NRAS and HRAS, encode proteins responsible for the regulation of growth, differentiation and survival of many cell types. The HRAS and KRAS oncogene mutations are well defined, however, the clinical significance of RAS expressions in non-small-cell lung cancer (NSCLC) is still uncertain. METHODS: A total of 39 whole blood samples of NSCLC (the investigated group), collected at three points of time: at the time of diagnosis, 100 days and 1 year after the surgery as well as 35 tissue samples obtained during the surgery were included in this study. HRAS and KRAS genes mRNA expression were assessed using quantitative real-time polymerase chain reaction techniques. RESULTS: Increased relative HRAS mRNA level in blood was found significantly more frequently in the group of smokers (p = 0.008). Patients with squamous cell carcinoma subtypes of NSCLC were more likely to show an overexpression of HRAS gene in blood, but not statistically significant (p = 0.065). In tumor tissue overexpression of HRAS gene was associated with adenocarcinoma subtype (p = 0.049). No statistically significant associations were found for the expression of KRAS with any clinicopathological parameters, except the age of patients, within the study. There were no differences between the relative HRAS and KRAS genes expression levels in blood samples taken from the same patients during the 3 observation points, as well as between blood collected from patients before surgery and tissue samples obtained during operation. CONCLUSION: The potential associations between high HRAS expression levels, age, smoking status and histological type of cancer were observed, which emphasizes the need for further study of the RAS family. Therefore, subsequent research involving larger numbers of patients and a longer follow-up, as well as multicenter study are necessary to confirm our findings.
BACKGROUND: The RAS family protooncogenes, including KRAS, NRAS and HRAS, encode proteins responsible for the regulation of growth, differentiation and survival of many cell types. The HRAS and KRAS oncogene mutations are well defined, however, the clinical significance of RAS expressions in non-small-cell lung cancer (NSCLC) is still uncertain. METHODS: A total of 39 whole blood samples of NSCLC (the investigated group), collected at three points of time: at the time of diagnosis, 100 days and 1 year after the surgery as well as 35 tissue samples obtained during the surgery were included in this study. HRAS and KRAS genes mRNA expression were assessed using quantitative real-time polymerase chain reaction techniques. RESULTS: Increased relative HRAS mRNA level in blood was found significantly more frequently in the group of smokers (p = 0.008). Patients with squamous cell carcinoma subtypes of NSCLC were more likely to show an overexpression of HRAS gene in blood, but not statistically significant (p = 0.065). In tumor tissue overexpression of HRAS gene was associated with adenocarcinoma subtype (p = 0.049). No statistically significant associations were found for the expression of KRAS with any clinicopathological parameters, except the age of patients, within the study. There were no differences between the relative HRAS and KRAS genes expression levels in blood samples taken from the same patients during the 3 observation points, as well as between blood collected from patients before surgery and tissue samples obtained during operation. CONCLUSION: The potential associations between high HRAS expression levels, age, smoking status and histological type of cancer were observed, which emphasizes the need for further study of the RAS family. Therefore, subsequent research involving larger numbers of patients and a longer follow-up, as well as multicenter study are necessary to confirm our findings.
Authors: Xiao Yu Wu; Wen Tao Liu; Zhen Feng Wu; Che Chen; Jia Yun Liu; Guan Nan Wu; Xue Quan Yao; Fu Kun Liu; Gang Li Journal: Am J Cancer Res Date: 2016-09-01 Impact factor: 6.166