1
|
Meng M, Zhong K, Jiang T, Liu Z, Kwan HY, Su T. The current understanding on the impact of KRAS on colorectal cancer. Biomed Pharmacother 2021; 140:111717. [PMID: 34044280 DOI: 10.1016/j.biopha.2021.111717] [Citation(s) in RCA: 51] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Revised: 05/06/2021] [Accepted: 05/07/2021] [Indexed: 02/07/2023] Open
Abstract
KRAS (kirsten rat sarcoma viral oncogene) is a member of the RAS family. KRAS mutations are one of most dominant mutations in colorectal cancer (CRC). The impact of KRAS mutations on the prognosis and survival of CRC patients drives many research studies to explore potential therapeutics or target therapy for the KRAS mutant CRC. This review summarizes the current understanding of the pathological consequences of the KRAS mutations in the development of CRC; and the impact of the mutations on the response and the sensitivity to the current front-line chemotherapy. The current therapeutic strategies for treating KRAS mutant CRC, the difficulties and challenges will also be discussed.
Collapse
Affiliation(s)
- Mingjing Meng
- Guangdong Key Laboratory for Translational Cancer Research of Chinese Medicine, Joint Laboratory for Translational Cancer Research of Chinese Medicine of the Ministry of Education of the People's Republic of China, International Institute for Translational Chinese Medicine, School of Pharmaceutical Science, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, China
| | - Keying Zhong
- Guangdong Key Laboratory for Translational Cancer Research of Chinese Medicine, Joint Laboratory for Translational Cancer Research of Chinese Medicine of the Ministry of Education of the People's Republic of China, International Institute for Translational Chinese Medicine, School of Pharmaceutical Science, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, China
| | - Ting Jiang
- Guangdong Key Laboratory for Translational Cancer Research of Chinese Medicine, Joint Laboratory for Translational Cancer Research of Chinese Medicine of the Ministry of Education of the People's Republic of China, International Institute for Translational Chinese Medicine, School of Pharmaceutical Science, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, China
| | - Zhongqiu Liu
- Guangdong Key Laboratory for Translational Cancer Research of Chinese Medicine, Joint Laboratory for Translational Cancer Research of Chinese Medicine of the Ministry of Education of the People's Republic of China, International Institute for Translational Chinese Medicine, School of Pharmaceutical Science, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, China; Guangdong-Hong Kong-Macau Joint Lab on Chinese Medicine and Immune Disease Research, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, China.
| | - Hiu Yee Kwan
- Centre for Cancer and Inflammation Research, School of Chinese Medicine, Hong Kong Baptist University, Hong Kong, China.
| | - Tao Su
- Guangdong Key Laboratory for Translational Cancer Research of Chinese Medicine, Joint Laboratory for Translational Cancer Research of Chinese Medicine of the Ministry of Education of the People's Republic of China, International Institute for Translational Chinese Medicine, School of Pharmaceutical Science, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, China; Guangdong-Hong Kong-Macau Joint Lab on Chinese Medicine and Immune Disease Research, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, China.
| |
Collapse
|
2
|
Wang J, Yu S, Jiao S, Lv X, Ma M, Zhu BZ, Du Y. Characterization of TCHQ-induced genotoxicity and mutagenesis using the pSP189 shuttle vector in mammalian cells. Mutat Res 2011; 729:16-23. [PMID: 21924276 DOI: 10.1016/j.mrfmmm.2011.08.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2011] [Revised: 08/17/2011] [Accepted: 08/26/2011] [Indexed: 01/29/2023]
Abstract
Tetrachlorohydroquinone (TCHQ) is a major toxic metabolite of the widely used wood preservative, pentachlorophenol (PCP), and it has also been implicated in PCP genotoxicity. However, the underlying mechanisms of genotoxicity and mutagenesis induced by TCHQ remain unclear. In this study, we examined the genotoxicity of TCHQ by using comet assays to detect DNA breakage and formation of TCHQ-DNA adducts. Then, we further verified the levels of mutagenesis by using the pSP189 shuttle vector in A549 human lung carcinoma cells. We demonstrated that TCHQ causes significant genotoxicity by inducing DNA breakage and forming DNA adducts. Additionally, DNA sequence analysis of the TCHQ-induced mutations revealed that 85.36% were single base substitutions, 9.76% were single base insertions, and 4.88% were large fragment deletions. More than 80% of the base substitutions occurred at G:C base pairs, and the mutations were G:C to C:G, G:C to T:A or G:C to A:T transversions and transitions. The most common types of mutations in A549 cells were G:C to A:T (37.14%) and A:T to C:G transitions (14.29%) and G:C to C:G (34.29%) and G:C to T:A (11.43%) transversions. We identified hotspots at nucleotides 129, 141, and 155 in the supF gene of plasmid pSP189. These mutation hotspots accounted for 63% of all single base substitutions. We conclude that TCHQ induces sequence-specific DNA mutations at high frequencies. Therefore, the safety of using this product would be carefully examined.
Collapse
Affiliation(s)
- Jing Wang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, PR China.
| | | | | | | | | | | | | |
Collapse
|
3
|
Tompkins EM, McLuckie KIE, Jones DJL, Farmer PB, Brown K. Mutagenicity of DNA adducts derived from ethylene oxide exposure in the pSP189 shuttle vector replicated in human Ad293 cells. Mutat Res 2009; 678:129-37. [PMID: 19477295 DOI: 10.1016/j.mrgentox.2009.05.011] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2009] [Accepted: 05/19/2009] [Indexed: 12/26/2022]
Abstract
Ethylene oxide (EO) is a widely used chemical intermediate also formed endogenously from ethylene metabolism. Despite conflicting epidemiological evidence, EO is classified by the IARC as a human carcinogen. The mutagenicity and carcinogenicity of EO is attributed to direct reaction with DNA and formation of multiple 2-hydroxyethyl (HE) DNA adducts. However, the actual lesions responsible for the reported mutagenicity of EO have not been established. This study used the supF mutation assay to investigate the biological relevance of low levels of EO-induced DNA adducts in human Ad293 cells, with respect to the type and level of each HE adduct present. Initial experiments were conducted using pSP189 plasmid containing up to 290 N7-HEGuanine (N7-HEG) adducts/10(6) nucleotides, which far exceeds that typically detected in human DNA. No other HE-lesions were detectable using our validated LC-MS/MS assay. Replication in cells failed to produce a statistically significant increase in relative mutation frequency, above background rates in the solvent control. Furthermore, the mutation spectrum compiled for EO-treated plasmid (10-2000muM) did not differ significantly from the spontaneous distribution, suggesting EO is not strongly mutagenic in this system. Under refined reaction conditions using higher EO concentrations capable of inducing detectable levels of N1-HEdA, O(6)-HEdG and N3-HEdU along with N7-HEG, there was a significant dose-related increase in relative mutation frequency above background (3.76- and 5.30-fold at 10 and 30mM, respectively). EO treatment appeared associated with an elevated frequency of GC-->CG mutations and the occurrence of substitutions at AT base pairs. Additionally, there was a distinct GC-->TA mutational hotspot in the 10mM EO spectrum. Overall, the results suggest a certain level of promutagenic adducts must be attained before mutations become detectable above background, indicating that N7-HEG is not a promutagenic lesion, and support a role for the minor products of DNA hydroxyethylation in the generation of base substitutions by EO.
Collapse
Affiliation(s)
- Elaine M Tompkins
- Department of Cancer Studies and Molecular Medicine, University of Leicester, Leicester, LE2 7LX, UK
| | | | | | | | | |
Collapse
|