HUMAN LUNG, BLADDER AND HEAD AND NECK TUMORS AS COMPARED TO THEIR ADJACENT NORMAL-TISSUES HAVE ELEVATED AP-1 ACTIVITY AND RECOGNIZE SEQUENCE ELEMENTS OF HIV-1 LTR

We have previously reported the specific binding of nuclear factor AP- 1 isolated from human breast MDA MB 468 and HeLa cervical tumor cell l ines to oligonucleotides complementary to three newly elucidated seque nces within the HIV-1 LTR. These synthesized oligonucleotides, which b ear high homology to the AP-1 recognition sequence, were used in the p resent study in gel retardation assays together with unfractionated nu clear protein extracts from human lung, bladder and head and neck tumo rs and adjacent normal tissue to study the role of the AP-1 protein in the regulation of HIV-1 expression. We found increased binding of AP- 1 to these oligonucleotides in 9/12 lung tumors, 9/14 bladder tumors a nd 7/7 head and neck tumors as compared to adjacent normal tissues. Th is confirms previous results obtained when using MDA MB 468 and HeLa n uclear protein extracts. These results indicate that, AP-1 could be co ntributing to the HIV-1 transcriptional regulation through its interac tion with the AP-I binding sites of HIV-I LTR.