The Fourth Military Medical University, China
Title: Carcinogenesis by stem cell misplacement- A novel cancer theory and its implications
Rui-An Wang received his M.D degree from Nanfang Medical University, and his Ph.D degree from the 3rd Military Medical University of China. He had been a lecturer of histology for years and then did his postdoctoral training in USA, at M.D.Anderson Cancer Center and worked as a faculty there for eight years. His scientific research experience has been very extensive, as in the field of endocrinology, male reproductive biology, developmental biology and cancer biology. His publications include those high rank journals as Nature, Nature Cell Biology, EMBO J, JCB, PNAS, Oncogene, etc. He is now a professor of pathology of the Fourth Military Medical University of China. What is special of him is that he proposed a new cancer theory, the stem cell misplacement theory, which posits that in situ carcinoma is not cancer, nor the origin of invasive cancer. The invasive cancer grows out de novo in the stroma fromdislodged epithelial stem cells. Apoptosis, instead of being a barrier of carcinogenesis as generally believed, stimulates carcinogenesis, cancer growth and metastasis.
For rather a long period of time, it has been widely accepted that cancer was caused by gene mutations which is termed somatic mutation theory (SMT). But now the SMT theory has met with increasing doubts, disbelieves, and been facing challenges from other alternative theories. I here from a pathological perspective, and with the evidences from molecular pathology, histopathology, and epidemiology, show that the 80 year old paradigm of carcinogenesis process from atypia to in situ carcinoma to invasive cancer does not hold up. Since 90% of the human cancers are epithelially derived \"carcinomas\", the turnover of this paradigm naturally negates the SMT theory for SMT sits on this model. The invasive cancer grows out in the stroma de novo from misplaced stem cells rather than deriving from the transformed in situ carcinoma cells. Also, I will show evidences that cancer cells are not so-believed \"apoptosis-resistant\", but rather \"short-lived sick cells\". In fact, it is the increased cell death which makes the cancer cells proliferate ceaselessly to compensate for the cell loss, and move to new locations for better chance of survival. I design this novel cancer theory as SCMT, stem cell misplacement theory. This theory is backed by huge amount of solid evidences and will bring revolutionary conceptual changes to our understanding and treatment of cancer, e.g., in situ carcinomas are not genuine cancer biologically, thus should not be treated the same as cancer.