The Topology of Mutated Driver Pathways
This work addresses the need for systematic comparisons of cancer pathways, potentially enabling new hypotheses in oncology, though it is incremental in applying topology to a known bottleneck.
The authors tackled the problem of understanding relationships between mutated driver pathways in different cancers by developing a novel topological framework, finding that the pathway space for Acute myeloid leukemia is homotopy equivalent to a sphere and for Glioblastoma multiforme to a genus-2 surface.
Much progress has been made, and continues to be made, towards identifying candidate mutated driver pathways in cancer. However, no systematic approach to understanding how candidate pathways relate to each other for a given cancer (such as Acute myeloid leukemia), and how one type of cancer may be similar or different from another with regard to their respective pathways (Acute myeloid leukemia vs. Glioblastoma multiforme for instance), has emerged thus far. Our work attempts to contribute to the understanding of {\em space of pathways} through a novel topological framework. We illustrate our approach, using mutation data (obtained from TCGA) of two types of tumors: Acute myeloid leukemia (AML) and Glioblastoma multiforme (GBM). We find that the space of pathways for AML is homotopy equivalent to a sphere, while that of GBM is equivalent to a genus-2 surface. We hope to trigger new types of questions (i.e., allow for novel kinds of hypotheses) towards a more comprehensive grasp of cancer.