KRAS and neoplasm: Apart from genetic alterations associated with spontaneous tumor development, it has been increasingly appreciated that KRAS mutation also exhibits a broad impact on the tumor microenvironment, which helps to promote and maintain the malignancy of cancer (Young et al., 2013; Kortlever et al., 2017; Ambrogio et al., 2018; Dias Carvalho et al., 2019).