At the Scientific American guest blog, University of Illinois at Chicago researcher Jalees Rehman describes a new paper he and his colleagues published in the FASEB Journal on the role of mitochondrial networks in lung cancer. One doesn't usually think of mitochondria as forming networks, Rehman says, but previous work done by his colleague Stephen Archer had shown that mitochondria in most cancer cells were small and fragmented, whereas healthy cells contained "elongated, filamentous-like mitochondria that formed large intact networks." The cause and significance of this, however, was unknown, he adds.
By working with other researchers, Rehman and Archer determined that lung cancer cells over-express the mitochondrial fission protein Drp-1, compared to healthy cells, and found that inhibition of Drp-1 in cells reversed mitochondrial fragmentation and restored mitochondrial networks in malignant cells to levels similar to those in healthy cells. "Importantly, inhibiting mitochondrial fission resulted in a cell cycle arrest of cancer cells and markedly reduced cancer cell proliferation," Rehman adds. "As with any research, our study also points towards many unanswered questions, some of them highlighting the importance of how the nucleus communicates with other organelles."