1. IL-6 and MYC collaborate in plasma cell tumor formation in mice
by Sebastian Rutsch, Vishala T. Neppalli, Dong-Mi Shin, Wendy DuBois, Herbert C. Morse, Hartmut Goldschmidt, and Siegfried Janz
Blood
Volume 115(9):
March 4, 2010
©2010 by American Society of Hematology

2. Incidence and onset of PCT. (A) Pilot study of tumor development in C
Incidence and onset of PCT. (A) Pilot study of tumor development in C.IL6/iMycEμ (▵) and C.IL6/iMycCα (○; n = 10 for both genotypes).
Incidence and onset of PCT. (A) Pilot study of tumor development in C.IL6/iMycEμ (▵) and C.IL6/iMycCα (○; n = 10 for both genotypes). (B) Survival studies of C.IL6/iMycEμ mice (n = 12) and C.iMycEμ mice (n = 20). Tumors arising in C.IL6/iMycEμ mice were invariable PCT. Most tumors developing in C.iMycEμ mice were high-grade B-cell lymphoma. (C) Survival studies of C.IL6/iMycCα mice (n = 21) and C.iMycCα mice (n = 24). All tumors in C.IL6/iMycCα mice were PCT. Most tumors from C.iMycCα mice were high-grade B-cell lymphoma. Transfer of the iMycCα TG from the original, mixed background that exhibited approximately 9% of tumors by 12 months of age13 onto strain C caused a dramatic increase in tumor incidence with minimal impact on tumor phenotype.
Sebastian Rutsch et al. Blood 2010;115:
©2010 by American Society of Hematology

3. Histopathology of PCT. (A) Mesenteric lymph node containing a plasmacytic PCT. Residual follicles, such as the one indicated by arrowheads, are displaced by large interfollicular expansions of mature plasma cells.
Histopathology of PCT. (A) Mesenteric lymph node containing a plasmacytic PCT. Residual follicles, such as the one indicated by arrowheads, are displaced by large interfollicular expansions of mature plasma cells. (B) High-power view of the interfollicular area containing aberrant, yet relatively small, plasma cells with varying amounts of cytoplasm. (C) Small bowel mucosa harboring a plasmablastic PCT with sheets of abnormal plasma cells infiltrating the mucosa. (D) High-power view showing atypical, large plasma cells with pleomorphic nuclei, prominent nucleoli, and varying amounts of cytoplasm, consistent with the diagnosis of plasmablastic PCT. Original magnification: ×4 (A,C) and ×40 (B,D). Final magnification: ×10 (A,C) and ×100 (B,D).
Sebastian Rutsch et al. Blood 2010;115:
©2010 by American Society of Hematology

4. Detection of serum paraproteins in sera of PCT-bearing mice.
Detection of serum paraproteins in sera of PCT-bearing mice. (A) Sera are from C.IL6/iMyc primary PCT (G0 samples) or tumor cell transplant recipients (G1 samples). (B) Paired G0/G1 samples from C.IL6/iMycEμ mice (lanes 1-4 and lane 13) or C.IL6/iMycCα mice (lanes 5-9 and 11-12). Lanes 10 and 14 contain samples from normal mice used as control. Paired G0 and G1 samples with shared M components are indicated by joined black boxes. M components only present in the G0 or G1 sample are indicated by white asterisks. The position of the γ protein band is indicated to the right and the anode/cathode to the left. C indicates serum from a control non–tumor-bearing mouse.
Sebastian Rutsch et al. Blood 2010;115:
©2010 by American Society of Hematology

5. Clonal diversification of PCT by isotype switching in situ as shown by serial tissue sections of a PCT that arose in a C.IL6/iMycCα mouse.
Clonal diversification of PCT by isotype switching in situ as shown by serial tissue sections of a PCT that arose in a C.IL6/iMycCα mouse. Ig heavy-chain–producing tumor cells or κ light-chain–producing tumor cells (top right) are immunolabeled in brown, using isotype-specific antibodies (original magnification, ×40). The bottom right panel presents a molecular scheme on the putative derivation of the γ2a+, γ2b+, and α+ subclones from the parental γ1+ clone. The possibility that CSR to Cϵ also occurred was not examined, but is an extremely rare event in other studies of PCT.
Sebastian Rutsch et al. Blood 2010;115:
©2010 by American Society of Hematology

6. Analysis of signal transduction pathways comparing PCT from C
Analysis of signal transduction pathways comparing PCT from C.IL6/iMyc and C.IL6 mice.
Analysis of signal transduction pathways comparing PCT from C.IL6/iMyc and C.IL6 mice. (A) Schematic overview of signaling pathways chosen for Western blot analyses (B-D). (B-D) Lane numbers correspond to normal splenic B cells (lane 1), PCT from C.IL6 mice (lanes 2-5), PCT from C.IL6/iMyc mice (lanes 6-12, with 3 tumors [lanes 6-8] contained on the blot shown to the left and 4 tumors [lanes 9-12] contained on the blot shown to the right), and commercial positive control (lane 13). Loading of equal protein amounts was documented individually for each Western blot by demonstrating comparable levels of β-actin in all lanes; only one example is shown (D bottom). Pathway screening included IL-6/STAT3/Bcl-XL (B), RAS/ERK (C), and MYC/p19/MDM2/p53 (D).
Sebastian Rutsch et al. Blood 2010;115:
©2010 by American Society of Hematology

7. Hierarchical clustering of PCT from C. IL6/iMyc mice (n = 11) and C
Hierarchical clustering of PCT from C.IL6/iMyc mice (n = 11) and C.IL6 mice (n = 10) based on global gene expression analysis.
Hierarchical clustering of PCT from C.IL6/iMyc mice (n = 11) and C.IL6 mice (n = 10) based on global gene expression analysis. Dendrogram at the top shows the samples studied, and their relationships based on similarities in gene expression. C.IL6/iMyc samples included 7 primary (G0) and 4 transplanted (2 G1, 2 G2) tumors. Dendrogram at the left shows the expression patterns of genes across all samples with intensities depicted according to the color scale at the top. The bars above the heat map are color-coded according to genotype and labeled with array numbers.
Sebastian Rutsch et al. Blood 2010;115:
©2010 by American Society of Hematology

8. Plasma cell hyperplasia in young, tumor-free C.IL6/iMyc mice.
Plasma cell hyperplasia in young, tumor-free C.IL6/iMyc mice. (A) Low-power view of an abnormal accumulation of plasmablasts and plasma cells in an enlarged peripheral lymph node of a 4-week-old C.IL6/iMycCα mouse (H&E stain; original magnification, ×20; final magnification, ×50). The 3 areas indicated by squares are shown below at higher power (final magnification, ×100; B-D). The arrow in panel C denotes cell that is undergoing division.
Sebastian Rutsch et al. Blood 2010;115:
©2010 by American Society of Hematology