LightCycier PCR for the Polymorph isms -308 and -238
in the TNF Alpha Gene and for the TNFB1/B2 Polymorphism
in the LTAlphaGene
LUKAS BESTMANN, NADER HELMY, FELICIA GAROFALO, AYNUR DEMIRTAS,
DIETER VONDERSCHMITT, FRIEDRICH E. MALY*
Introduction
Tumor necrosis factor alpha (TNF-a), a multifunctional cytokine of -17 kDa
composed of 157 amino acids, was initially identified as a macrophage-derived
serum protein mediating necrosis of solid tumors in mice and lysis of several
types of transformed cells in vitro. Indeed, recombinant tumor necrosis factor
alpha (rTNF-a) has potent antitumor activity in experimental studies on human
tumor xenografts. However, in humans, the administration of rTNF-a is hampered by severe systemic side effects, with the maximum tolerated dose being at
least tenfold less than the effective dose in animals [14]. Thus, systemic treatment
with TNF has not become a viable treatment modality for common human cancers. Isolated perfusion of the limbs allows the delivery of high -dose rTNF-a in a
closed system with acceptable side effects, and several studies have shown that
TNF-a, in combination with other agents such as melphalan, does possess activity against certain human tumors in vivo [12,20].
Apart from tumor biology, TNF-a is a major mediator of inflammation and
infection. Although also required for normal immune responses, the overexpression of TNF-a has severe pathological consequences. For example, it is responsible for some of the severe effects during Gram-negative sepsis and plasma levels
of TNF-a are positively correlated with severity and mortality in various illnesses such as malaria and leishmaniasis [4,18]. Furthermore, it is the major mediator of cachexia observed in tumor patients and congestive heart failure, hence its
earlier name Cachectin.
Tumor necrosis factor beta (TNF-~) or Lymphotoxin-a, a glycoprotein of
20-25 kDa with antiviral and antitumor activities, is produced by activated T and
B lymphocytes and shares sequence homologies and some biologic actions (such
as in vitro cytotoxicity against certain tumor cells) with TNF-a. Contrary to TNFa, TNF-~ is barely detectable in acute inflammation and sepsis [25], but forms
membrane-associated heteromeric complexes with Lymphotoxin-~ and has a
central role in the development of lymphoid organs and in chronic inflammation.
Lymphoid organ development and inflammation have previously been consid* Friedrich E. Maly (~) (e-mail: fma@ikc.unizh.ch)
Institute of Clinical Chemistry, University Hospital Zurich, R1imistrasse 100, 8091 Zurich,
Switzerland
in the TNF Alpha Gene and for the TNFB1/B2 Polymorphism
in the LTAlphaGene
LUKAS BESTMANN, NADER HELMY, FELICIA GAROFALO, AYNUR DEMIRTAS,
DIETER VONDERSCHMITT, FRIEDRICH E. MALY*
Introduction
Tumor necrosis factor alpha (TNF-a), a multifunctional cytokine of -17 kDa
composed of 157 amino acids, was initially identified as a macrophage-derived
serum protein mediating necrosis of solid tumors in mice and lysis of several
types of transformed cells in vitro. Indeed, recombinant tumor necrosis factor
alpha (rTNF-a) has potent antitumor activity in experimental studies on human
tumor xenografts. However, in humans, the administration of rTNF-a is hampered by severe systemic side effects, with the maximum tolerated dose being at
least tenfold less than the effective dose in animals [14]. Thus, systemic treatment
with TNF has not become a viable treatment modality for common human cancers. Isolated perfusion of the limbs allows the delivery of high -dose rTNF-a in a
closed system with acceptable side effects, and several studies have shown that
TNF-a, in combination with other agents such as melphalan, does possess activity against certain human tumors in vivo [12,20].
Apart from tumor biology, TNF-a is a major mediator of inflammation and
infection. Although also required for normal immune responses, the overexpression of TNF-a has severe pathological consequences. For example, it is responsible for some of the severe effects during Gram-negative sepsis and plasma levels
of TNF-a are positively correlated with severity and mortality in various illnesses such as malaria and leishmaniasis [4,18]. Furthermore, it is the major mediator of cachexia observed in tumor patients and congestive heart failure, hence its
earlier name Cachectin.
Tumor necrosis factor beta (TNF-~) or Lymphotoxin-a, a glycoprotein of
20-25 kDa with antiviral and antitumor activities, is produced by activated T and
B lymphocytes and shares sequence homologies and some biologic actions (such
as in vitro cytotoxicity against certain tumor cells) with TNF-a. Contrary to TNFa, TNF-~ is barely detectable in acute inflammation and sepsis [25], but forms
membrane-associated heteromeric complexes with Lymphotoxin-~ and has a
central role in the development of lymphoid organs and in chronic inflammation.
Lymphoid organ development and inflammation have previously been consid* Friedrich E. Maly (~) (e-mail: fma@ikc.unizh.ch)
Institute of Clinical Chemistry, University Hospital Zurich, R1imistrasse 100, 8091 Zurich,
Switzerland