Connexin 43 suppresses human glioblastoma cell growth by down-regulation of monocyte chemotactic protein 1, as discovered using protein array technology.
Previously, we demonstrated that connexin 43 (cx43) suppressed the growth of human glioblastoma cells. To investigate the molecular mechanisms involved in tumor suppression by cx43, we developed a human cytokine array system, which simultaneously detects the expression of 43 cytokines. By using this new technology, we analyzed the cx43-regulated genes in cx43-transfected cells. The cytokine arrays showed that expression of monocyte chemotactic protein-1 (MCP-1) was profoundly reduced in cx43-transfected cells. RT-PCR, immuno-Western blot, and cDNA microarrays further confirmed this observation. Addition of conditioned medium from control-transfected cells and recombinant MCP-1 to cx43-transfected cells significantly enhanced cx43-transfected cell proliferation and colony formation in soft agar. In contrast, addition of neutralization antibody against MCP-1 significantly inhibited cell proliferation in control-transfected cells. Our results suggested that MCP-1 is involved in the suppression of human glioblastoma cell growth by cx43.
Huang
Ruochun
R
Department of Gynecology and Obstetrics, Emory University School of Medicine, 1639 Pierce Drive, Atlanta, GA 30322, USA.
Lin
Ying
Y
Wang
Cheng C
CC
Gano
Jacob
J
Lin
Biaoyang
B
Shi
Qian
Q
Boynton
Alton
A
Burke
Jocelyn
J
Huang
Ruo-Pan
RP
D002455:Cell Division / Q000502:physiology; D018932:Chemokine CCL2 / Q000096:biosynthesis* / Q000235:genetics; D018031:Connexin 43 / Q000235:genetics / Q000502:physiology*; D016207:Cytokines / Q000096:biosynthesis / Q000235:genetics; D015536:Down-Regulation; D020869:Gene Expression Profiling; D005909:Glioblastoma / Q000235:genetics / Q000378:metabolism* / Q000473:pathology*; D006801:Humans; D020411:Oligonucleotide Array Sequence Analysis; D014162:Transfection
D018932:Chemokine CCL2; D018031:Connexin 43; D016207:Cytokines