Skip to Content
Merck

Recycling Endosomes in Mature Epithelia Restrain Tumorigenic Signaling.

Cancer research (2019-06-27)
Luca D'Agostino, Yingchao Nie, Sayantani Goswami, Kevin Tong, Shiyan Yu, Sheila Bandyopadhyay, Juan Flores, Xiao Zhang, Iyshwarya Balasubramanian, Ivor Joseph, Ryotaro Sakamori, Victoria Farrell, Qi Li, Chung S Yang, Bin Gao, Ronaldo P Ferraris, Ghassan Yehia, Edward M Bonder, James R Goldenring, Michael P Verzi, Lanjing Zhang, Y Tony Ip, Nan Gao
ABSTRACT

The effects of polarized membrane trafficking in mature epithelial tissue on cell growth and cancer progression have not been fully explored in vivo. A majority of colorectal cancers have reduced and mislocalized Rab11, a small GTPase dedicated to trafficking of recycling endosomes. Patients with low Rab11 protein expression have poor survival rates. Using genetic models across species, we show that intact recycling endosome function restrains aberrant epithelial growth elicited by APC or RAS mutations. Loss of Rab11 protein led to epithelial dysplasia in early animal development and synergized with oncogenic pathways to accelerate tumor progression initiated by carcinogen, genetic mutation, or aging. Transcriptomic analysis uncovered an immediate expansion of the intestinal stem cell pool along with cell-autonomous Yki/Yap activation following disruption of Rab11a-mediated recycling endosomes. Intestinal tumors lacking Rab11a traffic exhibited marked elevation of nuclear Yap, upd3/IL6-Stat3, and amphiregulin-MAPK signaling, whereas suppression of Yki/Yap or upd3/IL6 reduced gut epithelial dysplasia and hyperplasia. Examination of Rab11a function in enteroids or cultured cell lines suggested that this endosome unit is required for suppression of the Yap pathway by Hippo kinases. Thus, recycling endosomes in mature epithelia constitute key tumor suppressors, loss of which accelerates carcinogenesis. SIGNIFICANCE: Recycling endosome traffic in mature epithelia constitutes a novel tumor suppressing mechanism.

MATERIALS
Product Number
Brand
Product Description

Sigma-Aldrich
Anti-RAB11B antibody produced in rabbit, Prestige Antibodies® Powered by Atlas Antibodies, affinity isolated antibody
Sigma-Aldrich
Citric acid, ACS reagent, ≥99.5%
Sigma-Aldrich
Donkey serum