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Tumorigenic cells are common in mouse MPNSTs but their frequency depends upon tumor genotype and assay conditions.

ABSTRACT: Tumor-initiating cells have been suggested to be rare in many cancers. We tested this in mouse malignant peripheral nerve sheath tumors (MPNSTs) and found that 18% of primary and 49% of passaged MPNST cells from Nf1(+/-); Ink4a/Arf(-/-) mice formed tumors upon transplantation, whereas only 1.8% to 2.6% of MPNST cells from Nf1(+/-); p53(+/-) mice did. MPNST cells of both genotypes require laminin binding to ?1-integrin for clonogenic growth. Most MPNST cells from Nf1(+/-); Ink4a/Arf(-/-) mice expressed laminin, whereas most MPNST cells from Nf1(+/-); p53(+/-) mice did not. Exogenous laminin increased the percentage of MPNST cells from Nf1(+/-); p53(+/-) but not Nf1(+/-); Ink4a/Arf(-/-) mice that formed tumorigenic colonies. Tumor-forming potential is common among MPNST cells, but the assay conditions required to detect it vary with tumor genotype.

SUBMITTER: Buchstaller J

PROVIDER: S-EPMC3285409 | biostudies-literature | 2012 Feb

REPOSITORIES: biostudies-literature

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Tumorigenic cells are common in mouse MPNSTs but their frequency depends upon tumor genotype and assay conditions.

Buchstaller Johanna J McKeever Paul E PE Morrison Sean J SJ

Cancer cell 20120201 2

Tumor-initiating cells have been suggested to be rare in many cancers. We tested this in mouse malignant peripheral nerve sheath tumors (MPNSTs) and found that 18% of primary and 49% of passaged MPNST cells from Nf1(+/-); Ink4a/Arf(-/-) mice formed tumors upon transplantation, whereas only 1.8% to 2.6% of MPNST cells from Nf1(+/-); p53(+/-) mice did. MPNST cells of both genotypes require laminin binding to β1-integrin for clonogenic growth. Most MPNST cells from Nf1(+/-); Ink4a/Arf(-/-) mice exp ...[more]

PMID: 22340596

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