Early cancer intervention relies on identifying the molecular signals that transform precancerous cells into tumors. Preneoplastic cells (PNCs) have been identified in the patched (ptc) mutant mouse, which is a model for medulloblastoma. Interestingly, only 15% of these mice develop tumors, but the variable susceptibility to disease is not understood. In order to study the fate of non-transformed PNCs in vivo, researchers created and studied ptc mutant mice that express a reporter gene to trace PNCs during development. They found that PNCs could give rise to tumors, but primarily differentiate. They also found that N-myc promotes tumor progression and might be a key determinant of tumorigenesis.

Kessler
JD
,
Hasegawa
H
,
Brun
SN
,
Yang
ZJ
,
Dutton
JW
,
Wang
F
,
Wechsler-Reya
RJ
N-myc alters the fate of preneoplastic cells in a mouse model of medulloblastoma
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Genes Dev
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23
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