SCIENCE@home

Statin-induced GGPP depletion blocks macropinocytosis and starves cells with oncogenic defects

Zhihua Jiao,H. Cai,Y. Long,O. K. Sirka,Veena Padmanaban,A. Ewald,P. Devreotes

Published 2020 in Proceedings of the National Academy of Sciences of the United States of America

ABSTRACT

Significance Our studies establish a connection between two isolated observations that 1) statins, taken by millions to lower cholesterol, have antitumor activity and 2) Ras-induced macropinocytosis is important in tumorigenesis. We discover that by depleting GGPP required for pseudopod extension and macropinocytosis, statins selectively kill cells with oncogenic defects by limiting nutrient uptake. Cancer cells display novel characteristics which can be exploited for therapeutic advantage. Isolated studies have shown that 1) the mevalonate pathway and 2) increased macropinocytosis are important in tumorigenesis, but a connection between these two observations has not been envisioned. A library screen for compounds that selectively killed Dictyostelium pten− cells identified pitavastatin. Pitavastatin also killed human breast epithelial MCF10A cells lacking PTEN or expressing K-RasG12V, as well as mouse tumor organoids. The selective killing of cells with oncogenic defects was traced to GGPP (geranylgeranyl diphosphate) depletion. Disruption of GGPP synthase in Dictyostelium revealed that GGPP is needed for pseudopod extension and macropinocytosis. Fluid-phase uptake through macropinocytosis is lower in PTEN-deleted cells and, as reported previously, higher in cells expressing activated Ras. Nevertheless, uptake was more sensitive to pitavastatin in cells with either of these oncogenic mutations than in wild-type cells. Loading the residual macropinosomes after pitavastatin with high concentrations of protein mitigated the cell death, indicating that defective macropinocytosis leads to amino acid starvation. Our studies suggest that the dependence of cancer cells on the mevalonate pathway is due to the role of GGPP in macropinocytosis and the reliance of these cells on macropinocytosis for nutrient uptake. Thus, inhibition of the networks mediating these processes is likely to be effective in cancer intervention.

PUBLICATION RECORD

CITATION MAP

EXTRACTION MAP

CLAIMS

  • No claims are published for this paper.

CONCEPTS

  • No concepts are published for this paper.

REFERENCES

Showing 1-42 of 42 references · Page 1 of 1

CITED BY

Showing 1-55 of 55 citing papers · Page 1 of 1