title: Invasive cancers are not necessarily from preformed in situ tumours - an alternative way of carcinogenesis from misplaced stem cells.
abstract: Cancers are thought to be the result of accumulated gene mutations in cells. Carcinomas, which are cancers arising from epithelial tissues usually go through several stages of development: atypical hyperplasia, carcinoma in situ and then invasive carcinoma, which might further metastasize. However, we think that the present pathological data are enough to prove that there might be an alternative way of carcinogenesis. We propose that majority of invasive cancers arise in the connective tissue stroma de novo, from the misplaced epithelial stem cells which come to the wrong land of connective tissue stroma by accident. The in situ carcinomas, which are mostly curable, should not be considered genuine cancer, but rather as quasi-cancer. We design this new theory of carcinogenesis as the stem cell misplacement theory (SCMT). Our SCMT theory chains together other carcinogenesis theories such as the inflammation-cancer chain, the stem cell theory and the tissue organization field theory. However, we deny the pathway of somatic mutation theory as the major pathway of carcinogenesis.
authors.affiliation: State Key Lab of Cancer Biology, The Fourth Military Medical University, Xi'an, Shaanxi Pr., China. wangra@fmmu.edu.cn
authors.forename: Rui-An
authors.initials: RA
authors.lastname: Wang
authors.forename: Zeng-Shan
authors.initials: ZS
authors.lastname: Li
authors.forename: Hui-Zhong
authors.initials: HZ
authors.lastname: Zhang
authors.forename: Ping-Ju
authors.initials: PJ
authors.lastname: Zheng
authors.forename: Qin-Long
authors.initials: QL
authors.lastname: Li
authors.forename: Jian-Guo
authors.initials: JG
authors.lastname: Shi
authors.forename: Qing-Guo
authors.initials: QG
authors.lastname: Yan
authors.forename: Jing
authors.initials: J
authors.lastname: Ye
authors.forename: Jing-Bo
authors.initials: JB
authors.lastname: Wang
authors.forename: Ying
authors.initials: Y
authors.lastname: Guo
authors.forename: Xiao-Feng
authors.initials: XF
authors.lastname: Huang
authors.forename: Ying-Hao
authors.initials: YH
authors.lastname: Yu
mesh_terms: D000818:Animals; D001485:Basement Membrane; D001943:Breast Neoplasms / Q000473:pathology; D063646:Carcinogenesis / Q000473:pathology*; D018270:Carcinoma, Ductal, Breast / Q000473:pathology; D003238:Connective Tissue / Q000473:pathology; D018450:Disease Progression; D004847:Epithelial Cells / Q000166:cytology; D058750:Epithelial-Mesenchymal Transition; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007249:Inflammation / Q000473:pathology; D051379:Mice; D009154:Mutation; D009361:Neoplasm Invasiveness; D009362:Neoplasm Metastasis; D009369:Neoplasms / Q000473:pathology*; D013234:Stem Cells / Q000166:cytology*; D019098:Telomerase / Q000378:metabolism
chemical_list: D019098:Telomerase
keywords: Carcinogenesis; DCIS; basement membrane; breast cancer; quasi-cancer; stem cell misplacement theory; stroma