HB1.F3.C1 cells injected intravenously localized to microscopic bone marrow disease.

<div><p>Concordant detection of v-<i>myc</i> (HB1.F3.C1 cells) by PCR and TH expression (neuroblastoma cells) by RT-PCR in bone marrow specimens.</p> <p>Bone marrow samples isolated from animals injected with HB1.F3.C1 cells were analyzed for the presence of v-<i>myc</i> (HB1.F3.C1 cells) or the expression of TH (NB-1643 cells).</p> <p>HB1.F3.C1 cells were present in the bone marrow only when tumor cells were also present.</p> <p>HB1.F3.C1 cells were not detected in the bone marrow of non-tumor-bearing animals.</p> <p>The positive controls (+) were DNA extracted from HB1.F3.C1 cells for v-<i>myc</i>, and RNA extracted from NB-1691 cells for TH.</p> <p>The negative controls (−) contained no DNA or RNA template, respectively.</p></div

HB1.F3.C1 cells transduced with an adenoviral multiplicity of infection of 5, 10, or 20 retain their tumor-tropism toward conditioned medium from SK-N-AS neuroblastoma cells.

<p>Bars represent the average number of migrated cells±SEM of triplicate wells in modified Boyden chamber assays.</p

Es1^e SCID mice injected intravenously with neuroblastoma cells develop multiple disseminated tumors.

<div><p>SK-N-AS cells (5×10⁵) transduced to express luciferase were injected into tail veins.</p> <p>One month following injection of tumor cells, mice were injected intraperitoneally with luciferin and imaged using a Xenogen IVIS imaging system, according the directions of the manufacturer.</p> <p>Multiple tumors were present in 100% of mice.</p> <p>Two representative mice are shown.</p></div

Treatment protocol of HB1.F3.C1/AdCMVrCE/CPT-11 NDEPT.

<div><p>One day prior to being used in treatments, cells were transduced with the AdCMVrCE construct (see text).</p> <p>The treatment schedule was based on the time-course of expression of the secreted form of rCE, following adenoviral transduction of HB1.F3.C1 cells (Danks, unpublished observation) and on a schedule of administration of CPT-11 that has been shown to be relatively effective for neuroblastoma patients <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0000023#pone.0000023-Furman1" target="_blank">[35]</a>.</p></div

HB1.F3.C1 cells target macroscopic metastatic neuroblastoma in the bone marrow.

<div><p>X-ray image of hind limb of a mouse with advanced stage neuroblastoma (Day 82; left panel, scale bar: 1 cm).</p> <p>Confirmation of the tumor mass as human SK-N-AS neuroblastoma cells was performed by immunohistochemistry using anti-human mitochondria antibody (not shown).</p> <p>The CM-DiI-labeled HB1.F3.C1 cells (red cells, injected into the tail vein 3 days prior to sacrifice) localized to tumor in the marrow (right panel; scale bar: 200 µm).</p></div

Schematic diagram of the protocol for NDEPT.

<div><p>Human neuroblastoma tumor cells are injected intravenously to produce disseminated tumors.</p> <p>At an appropriate time after injection of neuroblastoma cells, neural stem cells or neural progenitor cells transduced with adenovirus to express a prodrug-activating enzyme (in this study, a secreted form of rabbit carboxylesterase [rCE]) are injected intravenously.</p> <p>Following migration of stem cells or progenitor cells to tumor foci and a delay of 3–4 days to allow relatively high level expression of the prodrug-activating enzyme into the extracellular milieu at the tumor sites, mice are treated with the prodrug (in this study, CPT-11).</p> <p>The prodrug is activated selectively at tumor foci, to increase the therapeutic index of the prodrug.</p></div