| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
Short Communications |


From the Institute of Pathology/Tumor Immunology,*
University of Regensburg, Regensburg, Germany; Pharmaceutical Research
Gene Technology,
F. Hoffmann-LaRoche, Basel,
Switzerland; and the Institute of Pathology,
Technical University Dresden, Dresden, Germany
| Abstract |
|---|
|
|
|---|
| Introduction |
|---|
|
|
|---|
Earlier studies suggested that TNF acts
on the tumor-associated endogenic cells rather than directly on the
tumor cells because methylcholanthrene-induced fibrosarcomas, known to
be relatively insensitive to TNF-mediated cytotoxicity in
vitro, are extremely sensitive to the necrotizing effect in
vivo.7
Until now a TNF-mediated tumor cytotoxicity,
however, could not be fully excluded. In addition, it was demonstrated
that TNF-induced coagulation in the tumor vasculature may be one
potential mechanism for tumor necrosis.8
This was stressed
by the fact that necrosis was achieved through selective induction of
thrombosis within the tumor vessels by targeting procoagulant tissue
factor (TF), by means of a bispecific antibody to an experimentally
induced marker on tumor vascular endothelial cells.9
In a
less artificial system we could show that coagulation within the
vascular bed of the tumor correlated with the expression of tissue
factor (TF) on endothelial cells, which is known to be induced by TNF
in vivo.10
In addition, when TF expression was
inhibited by somatic gene transfer of I
B in this model, TNF-mediated
fibrin deposition was decreased and free blood flow could be
restored.11
Besides a direct endothelial cell stimulation
by LPS, TNF, or other cytokines, adhesion of lymphocytes to endothelium
or coculture of monocytes with endothelial cells can also induce TF
expression on endothelium.12-14
This, together with the
observation of TF expression on endothelial cells after TNFRp75
stimulation15
and the fact that activated monocytes also
express TF,16
leaves room for a potential role for both
leukocytes and endothelial cells in initiating tumor necrosis. However,
it is still unclear whether coagulation as a result of induction of TF
expression is the cause or rather a consequence of the disruption of
the tumor vasculature. Ruegg and co-workers demonstrated that TNF
reduces
vß3 integrin-mediated endothelial cell adhesion in
vitro, resulting in detachment and apoptotic cell
death.17
Such endothelial cell destruction has been
suggested to be the effector mechanism in the only antitumoral TNF
therapy of isolated limp perfusion currently used,18
which
points to the endothelium as a target for TNF-induced tumor necrosis.
Although in TNF-induced tumor necrosis a role of endothelial cells was suggested by a number of previous studies, neither a direct tumor cell cytotoxic activity nor a leukocyte-mediated event could be fully excluded until now. By using mice and tumor cells deficient for TNFRs and by generating bone marrow chimeric mice, we investigated the mechanism by which recombinant soluble mouse TNF, which, in contrast to human TNF, interacts with both the TNFRp55 and the TNFRp75, initiates tumor necrosis.
| Materials and Methods |
|---|
|
|
|---|
Female wild-type (wt) mice of strain C57BL/6 and C57BL/6 x 129/Sv were obtained from Charles River, Germany, and from RCC, Füllinsdorf, Switzerland, respectively. TNFRp55-deficient mice (TNFRp55-/-),19 (kindly provided by K. Pfeffer, Munich) and TNFRp75-deficient mice (TNFRp75-/-)20 have been back-crossed six times to C57BL/6. Mice deficient for both TNF receptors were obtained by crossing single TNFR-deficient mice and were of hybrid C57BL/6 x 129/Sv background. Mice used for tumor experiments were age- and sex-matched. All mice were fed with a standard diet, received water ad libitum, and were kept in the animal facility of the University of Regensburg according to institutional guidelines and in accordance with the German law for animal experimentation.
Reagents
Recombinant mouse (rm)TNF was expressed in Escherichia coli and purified according to standard procedures. The specific activity was 9 x 108 U/mg, as tested in the L929 TNF bioassay in the presence of 2 µg/ml actinomycin D. LPS contamination of the purified material was <0.16 µg/mg, as determined in a Limulus lysate turbidity assay.21 LPS from Salmonella minnesota (LPSW S. minnesota 9700) was purchased from Difco (Detroit, MI).
Tumors
The wtBFS-1 MethA-induced fibrosarcoma was generated in a female C57BL/6 mouse and the p55-/-BFS-1 MethA-induced fibrosarcoma in a female TNFRp55-/- mouse by injection of 1 mg of 3-methylcholanthrene (Sigma, Deisenhofen, Germany) dissolved in 200 µl tricaprylin (Sigma) i.d. in the back of a mouse essentially as described earlier.5 To adapt wtBFS-1 cells for growth in C57BL/6 x 129/Sv mice, wtBFS-1 cells were passaged three times in C57BL/6 x 129/Sv mice and named BFS-2c. The tumor cells were maintained in vitro in RPMI 1640 supplemented with 5% heat-inactivated fetal calf serum (all from Life Technologies, Eggenstein, Germany).
Tumor Experiments
Mice received 1.5 x 106 BFS-1, p55-/-BFS-1, or BFS-2c cells in 50 µl medium i.d. in the back, and tumors were allowed to grow for 911 days to reach a size approximately 8 mm in diameter before i.p. injection of rmTNF (5 µg) in 100 µl PBS or 100 µl PBS alone as a control. After 12 hours or 2 days, mice were sacrificed and the tumors were removed for immunohistochemistry or histology, respectively.
Histology
The tumors were excised, fixed overnight in 4% PBS-buffered formalin, and embedded in paraffin. For immunohistochemistry, dewaxed sections were treated with 0.05% pronase (Dako, Hamburg, Germany) (15 minutes, 37°C) before incubation with anti-von Willebrand factor (vWF) antibody (Dako) (serum dilution 1:400, 1 hour, 37°C) to look for vascular endothelial damage as described earlier.22 Central vertical sections (4 µm) were stained with hematoxylin and eosin and examined with a Leitz Axioplan microscope (x40 magnification). The percentage of necrotic area versus total tumor area of two sections per tumor was quantified using the image analysis software analySIS (Soft-Imaging Software GmbH, Münster, Germany). Tumors with >20% necrotic area were considered positive for tumor necrosis.
Leukocyte Adhesion in Vivo
Mice received rmTNF (5 µg) i.p. in 100 µl PBS or PBS alone as a control. After 4 hours, mice were sacrificed and the lungs were removed and processed like the tumors. The sections were examined with a Leitz Axioplan microscope (x160 magnification). Adherent leukocytes in vessels with an inner diameter of 50150 µm were counted, and the inner circumference of the vessels was measured using the image analysis software analySIS (Soft-Imaging Software GmbH). To quantify leukostasis, two sections per lung and at least five vessels per section were examined and expressed as adherent leukocytes per mm endothelium ± SE.
Adoptive Transfer of Bone Marrow Cells
Donor mice were sacrificed and the femurs were removed. The ends of the femurs were cut off, gently ground in medium, and filtered through a sieve (0.2-µm mesh) to remove bone fragments. The bone marrow cells were flushed out of the femurs with ice-cold RPMI 1640 containing 5% fetal calf serum, using a syringe. Bone marrow cells were pooled, washed twice, and resuspended in medium at a concentration of 108/ml. After lethal x-irradiation (10 Gy) recipient mice received 107 donor bone marrow cells i.v. in 100 µl medium into the tail vein. For the following 2 weeks drinking water was supplemented with 0.1 g/l neomycin sulfate (Sigma) and 10 mg/l polymycin (Sigma). Four weeks after reconstitution, mice were used for tumor experiments.
PCR
To determine the quality of the adoptive cell transfer, PCR of genomic DNA derived from leukocytes from reconstituted mice was performed to test for the presence or absence of either TNFR allele. Reconstituted mice were anesthetized and bled through the retroorbital plexus into 0.1 mol/L citrate buffer (pH 8). Genomic DNA was isolated from approximately 200 µl whole blood, using the Quiamp Blood Kit (Quiagen, Hilden, Germany), following the suppliers instructions. The following primers were used: gT6E515 (AGAAATGTCCCAGGTGATCTC), gT6IP2 (TTGCCAGACGTTTGCAAGCG), and HSVTK-AS (ATTCGGCAATGACAAGACGCTCC). PCR was carried out following the instructions from Perkin-Elmer (Applied Biosystems, Weiterstadt, Germany). By use of the primers gT6H515 and gT6IP2, a 600-bp fragment of the wt TNFRp55 allele was amplified. By use of the primers HSVTK-AS and gT6IP2, a 800-bp fragment of the mutated TNFRp55 allele was amplified. The annealing temperature for the primers used was 63°C (0.5 minutes) and 72°C (1.5 minutes) for the elongation reaction.
Statistics
P values were determined using Students t-test.
| Results and Discussion |
|---|
|
|
|---|
|
|
To analyze the TNF receptor-dependent effect of systemic rmTNF
treatment on the sequestration of peripheral blood leukocytes, the
occurrence of pulmonary leukostasis was quantified in wt and
TNFR-deficient mice 4 hours after TNF application. Administration of
rmTNF resulted in adhesion of leukocytes to lung vessels in wt and
TNFRp75-/- mice. However, as in tumor necrosis, soluble rmTNF was
not able to induce leukostasis in TNFRp55-/- mice (Figure 2B)
. To determine the role of
hematopoietic cells for mediating these rmTNF-induced effects, chimeric
mice were generated by adoptive bone marrow transplantation. Either
TNFRp55-/- mice received wt bone marrow cells or wt mice received
bone marrow cells from TNFRp55-/- donors. To test the successful
adoptive bone marrow cell transfer, the genotype of blood leukocytes in
chimeric mice was determined 4 weeks after reconstitution. In all
chimeric mice, specific bands of the donor genotype and the recipient
genotype were detectable, which was likely due to incomplete
reconstitution (Figure 2A)
. Nevertheless, adoptive transfer of
TNFRp55-positive bone marrow cells into TNFRp55-/- mice was
sufficient to restore rmTNF-induced sequestration of leukocytes in
TNFRp55-/- mice (Figure 2B)
, indicating that rmTNF was acting on the
hematopoietic cells for this function. In contrast, we could not induce
tumor necrosis with rmTNF in chimeric TNFRp55-/- mice, even after
reconstitution with wt bone marrow cells (Figure 3)
, whereas rmTNF caused tumor necrosis
in chimeric wt mice reconstituted with TNFRp55-/- bone marrow cells
as well as it did in wt mice reconstituted for control purposes with wt
bone marrow cells. LPS, in the same experiment, induced tumor necrosis
in TNFRp55-/- mice reconstituted with bone marrow from wt as well as
TNFRp55-/- mice, documenting the general ability for tumor necrosis
in such mice (data not shown).
|
|
in isolated limp perfusion of melanoma patients.17
From these studies, disruption of the tumor vasculature is discussed as
result of anoikis due to decreased
vß3-dependent endothelial cell
adhesion and ensuing detachment of these cells.17 In conclusion, we found that 1) rmTNF does not directly exert a cytotoxic effect on the tumor cells, 2) the TNFRp55 expression on hematopoietic cells was essential for TNF-induced leukocyte sequestration, 3) but not sufficient to mediate tumor necrosis. TNFR type 1-expressing endothelial cells lining the tumor vasculature are most likely the target cells for mediation of TNF-induced tumor necrosis.
| Footnotes |
|---|
Accepted for publication December 7, 1999.
| References |
|---|
|
|
|---|
expressed from an adenovirus vector induces an antitumor response with reduced toxicity. Cancer Gene Ther 1999, 6:465-474[Medline]
This article has been cited by other articles:
![]() |
M. Kneilling, R. Mailhammer, L. Hultner, T. Schonberger, K. Fuchs, M. Schaller, D. Bukala, S. Massberg, C. A. Sander, H. Braumuller, et al. Direct crosstalk between mast cell-TNF and TNFR1-expressing endothelia mediates local tissue inflammation Blood, August 20, 2009; 114(8): 1696 - 1706. [Abstract] [Full Text] [PDF] |
||||
![]() |
X. Zhao, M. Mohaupt, J. Jiang, S. Liu, B. Li, and Z. Qin Tumor Necrosis Factor Receptor 2-Mediated Tumor Suppression Is Nitric Oxide Dependent and Involves Angiostasis Cancer Res., May 1, 2007; 67(9): 4443 - 4450. [Abstract] [Full Text] [PDF] |
||||
![]() |
X. Wang, N. Li, H. Li, B. Liu, J. Qiu, T. Chen, and X. Cao Silencing of Human Phosphatidylethanolamine-Binding Protein 4 Sensitizes Breast Cancer Cells to Tumor Necrosis Factor-{alpha}-Induced Apoptosis and Cell Growth Arrest Clin. Cancer Res., October 15, 2005; 11(20): 7545 - 7553. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Dienst, A. Grunow, M. Unruh, B. Rabausch, J. E. Nor, J. W. U. Fries, and C. Gottstein Specific Occlusion of Murine and Human Tumor Vasculature by VCAM-1-Targeted Recombinant Fusion Proteins J Natl Cancer Inst, May 18, 2005; 97(10): 733 - 747. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. Gerl and D. L. Vaux Apoptosis in the development and treatment of cancer Carcinogenesis, February 1, 2005; 26(2): 263 - 270. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Mocellin, M. Provenzano, C. R. Rossi, P. Pilati, R. Scalerta, M. Lise, and D. Nitti Induction of Endothelial Nitric Oxide Synthase Expression by Melanoma Sensitizes Endothelial Cells to Tumor Necrosis Factor-Driven Cytotoxicity Clin. Cancer Res., October 15, 2004; 10(20): 6879 - 6886. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. Schwamberger, P. Hammerl, E. Ferber, M. Freudenberg, and C. Galanos TNF revisited: TNF-independent antitumor activity in sera of mice sensitized with Propionibacterium acnes and challenged with lipopolysaccharide J. Leukoc. Biol., December 1, 2003; 74(6): 1056 - 1063. [Abstract] [Full Text] |
||||
![]() |
P. Monti, B. E. Leone, F. Marchesi, G. Balzano, A. Zerbi, F. Scaltrini, C. Pasquali, G. Calori, F. Pessi, C. Sperti, et al. The CC Chemokine MCP-1/CCL2 in Pancreatic Cancer Progression: Regulation of Expression and Potential Mechanisms of Antimalignant Activity Cancer Res., November 1, 2003; 63(21): 7451 - 7461. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. C. Manegold, J. Hutter, S. A. Pahernik, K. Messmer, and M. Dellian Platelet-endothelial interaction in tumor angiogenesis and microcirculation Blood, March 1, 2003; 101(5): 1970 - 1976. [Abstract] [Full Text] [PDF] |
||||
![]() |
B. Stoelcker, T. Hehlgans, K. Weigl, H. Bluethmann, G. E. Grau, and D. N. Mannel Requirement for Tumor Necrosis Factor Receptor 2 Expression on Vascular Cells To Induce Experimental Cerebral Malaria Infect. Immun., October 1, 2002; 70(10): 5857 - 5859. [Abstract] [Full Text] [PDF] |
||||
![]() |
W.-H. Shen, J.-H. Zhou, S. R. Broussard, G. G. Freund, R. Dantzer, and K. W. Kelley Proinflammatory Cytokines Block Growth of Breast Cancer Cells by Impairing Signals from a Growth Factor Receptor Cancer Res., August 15, 2002; 62(16): 4746 - 4756. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. Hehlgans, B. Stoelcker, P. Stopfer, P. Muller, G. Cernaianu, M. Guba, M. Steinbauer, S. A. Nedospasov, K. Pfeffer, and D. N. Mannel Lymphotoxin-{beta} Receptor Immune Interaction Promotes Tumor Growth by Inducing Angiogenesis Cancer Res., July 15, 2002; 62(14): 4034 - 4040. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. Hallermalm, K. Seki, C. Wei, C. Castelli, L. Rivoltini, R. Kiessling, and J. Levitskaya Tumor necrosis factor-{alpha} induces coordinated changes in major histocompatibility class I presentation pathway, resulting in increased stability of class I complexes at the cell surface Blood, August 15, 2001; 98(4): 1108 - 1115. [Abstract] [Full Text] [PDF] |
||||
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |