18
Cell News 2/2015
for spindle geometry and orientation. Further work addressing
the role of microtubule dynamics in anchoring astral microtu-
bules to the cortex, which is pivotal for proper spindle orientati-
on, will be helpful to solve this important question.
Outlook
After we uncovered that increased microtubule plus end as-
sembly rates trigger CIN and the induction of whole chromo-
some aneuploidy in human cancer cells, it will be a premier
goal to systematically identify the cancer relevant genes and
pathways(s) that contribute to this intriguing phenotype. Clear-
ly, the CHK2-BRCA1-
AURKA
axis is important, but certainly just
the "tip of the iceberg". Due the wide-spread appearance of this
phenotype, we would expect that additional genes and pathways
will contribute to the alteration in microtubule dynamics. So
far, surprisingly little is known about the basic mechanisms of
microtubule plus end assembly and how plus end dynamics is
regulated. Only the systematic identification of regulators of
microtubule plus end assembly will provide a clearer picture of
the defects that are responsible for CIN in cancer cells. Those
genes, in particular oncogenes that contribute to an increase
in microtubule dynamics might be targeted in order to suppress
CIN. Since we found already means to experimentally restore
normal microtubule assembly rates in CIN cells we are now in
a position to address the long-standing question for the impact
of CIN on tumor behavior and on the ability of cancer cells to
adapt to various growth conditions and therapeutic regimens.
Acknowledgements
I am very grateful to all current and former members of my
lab for their excellent work during the last years. Without their
scientific enthusiasm the progress and success of our lab would
not have been possible. I would also like to thank the DFG for
their financial support, in particular for the support within the
Heisenberg program.
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About the author
Holger Bastians studied Biology at the Universities in Bayreuth
and Osnabrück. He earned his PhD at the German Cancer Re-
search Center in Heidelberg where he worked on the role of
protein phosphatases during the cell cycle. He then joined the
lab of Joan Ruderman as a postdoc at Harvard Medical School in
Boston, USA, and investigated the mechanisms of protein pro-
teolysis during mitosis. After returning to Germany, he started
his own laboratory focusing on mitotic chromosome segregati-
on in human cancer cells at the Institute for Molecular Biology
and Tumor Research (IMT) in Marburg. In 2008, he received a
Heisenberg fellowship of the DFG and in 2011 he became a Hei-
senberg-Professor at the Georg-August University in Göttingen
where he is now an appointed Professor for Cellular Oncology.
His work is currently focusing on the molecular causes and con-
sequences of chromosomal instability and aneuploidy in cancer
cells.
PRIZE WINNERS
Dorothea Fichter-Fechner (Binder Central Services GmbH & Co. KG),
Ralph Gräf (DGZ President), Holger Bastians
