The patterns of resistance-conferring mutations that are selected in HIV-1 reverse transcriptase (RT) by the racemates of 2′-dideoxy-3′-oxa-4′-thiocytidine (+/-)dOTC and its fluorinated derivative (+/-)dOTFC were characterized. Genotypic and phenotypic analyses of HIV-1 clinical isolates and HXB2D variants selected with (+/-)dOTC and (+/-)dOTFC were performed in primary cells and in the MT-2 T cell line. HIV-1 variants selected with (+/-)dOTC or (+/-)dOTFC displayed fivefold decreased susceptibility to the respective compounds. A substitution of methionine to valine was identified at position 184 (M184V) in variants selected with (+/-)dOTC. In contrast, a mutation of lysine to arginine at position 65 (K65R) was found in variants selected with (+/-)dOTFC. These patterns of selected mutations differ from those seen with the individual enantiomers. Studies with mutated recombinant HXB2D-M184V and -K65R confirmed that these mutations are important for phenotypic resistance in MT-2 cells. Clinical isolates that display resistance to (-)2′-deoxy-3′-thiacytidine (3TC) also showed cross-resistance to (+/-)dOTC and (+/-)dOTFC. These studies demonstrate that similar genotypes may be selected by the dOTC and dOTFC compounds to those with the structurally related drug 3TC.
ArionDBorkowGGuZWainbergMA & ParniakMA (1996) The K65R mutation confers increased DNA polymerase processivity to HIV-1 reverse transcriptase. Journal of Biological Chemistry271: 19860–19864.
2.
ArtsE JMaroisJ-PGuZLe GriceSFJ & WainbergMA (1996) Effects of 3′-deoxynucleotide 5′-triphosphate concentrations on chain termination by nucleoside analogs during human immunodeficiency virus type-1 reverse transcription of minus-strand strong-stop DNA. Journal of Virolology70: 712–720.
3.
BodenDHurleyAZhangLCaoYGuoYJonesETsayJIpJFarthingCLimoliKParkinN & MarkowitzM (1999) HIV-1 drug resistance in newly infected individuals. Journal of the American Medical Association282: 1135–1141.
4.
BoucherCABCammackNSchipperPSchuurmanRRousePWainbergMA & CameronJM (1993) High-level resistance to (-) enantiomeric 2′-deoxy-3′-thiacytidine in vitro is due to one amino acid substitution in the catalytic site of human immunodeficiency virus type 1 reverse transcriptase. Antimicrobial Agents & Chemotherapy37: 2231–2234.
5.
De MuysJ-MGoudreauHNguyen-BaNTaylorDLAhmedPSMansourTLocasCRichardNWainbergMA & RandoRF (1999) Anti-immunodeficiency virus type 1 activity, intracellular metabolism, and pharmacokinetic evaluation of 2′-deoxy-3′-oxa-4′-thiocytidine. Antimicrobial Agents & Chemotherapy43: 1835–1844.
6.
FisherAGCollaltiERatnerLGalloRC & Wong-StaalF (1985) A molecular clone of HTLV-III with biological activity. Nature316: 262–265.
7.
FitzgibbonJEHowellRMHaberzettlCASperberSJGockeDJ & DubinDT (1992) Human immunodeficiency virus type 1 pol gene mutations which cause decreased susceptibility to 2′,3′-dideoxycytidine. Antimicrobial Agents & Chemotherapy36: 153–157.
8.
GaoQGuZParniakMACameronJCammackNBoucherC & WainbergMA (1993) The same mutation that encodes low-level human immunodeficiency virus type 1 resistance to 2′,3′-dideoxyinosine and 2′,3′-dideoxycytidine confers high-level resistance to the (-)enantiomer of 2′,3′-dideoxy-3′-thiacytidineAntimicrobial Agents & Chemotherapy37: 1390–1392.
9.
GuZArtsEJParniakMA & WainbergMA (1995) Mutated K65R recombinant reverse transcriptase of human immunodeficiency virus type 1 shows diminished chain termination in the presence of 2′,3′-dideoxycytidine 5′-triphosphate and other drugs. Proceedings of the National Academy of Science USA92: 2760–2764.
10.
GuZGaoQFangHSalomonHParniakMAGoldbergECameronJ & WainbergMA (1994) Identification of a mutation at codon 65 in the IKKK motif of reverse transcriptase that encodes human immunodeficiency virus resistance to 2′,3′-dideoxycytidine and 2′,3′-dideoxy-3′-thiacytidine. Antimicrobial Agents & Chemotherapy38: 275–281.
11.
GuZGaoQLiXParniakMA & WainbergMA (1992) Novel mutation in the human immunodeficiency virus type 1 reverse transcriptase gene that encodes cross-resistance to 2′,3′-dideoxyi-nosine and 2′,3′-dideoxycytidine. Journal of Virology66: 7128–7135.
12.
HaoZCooneyDAHartmanNRPernoCFFridlandADeVicoALSarngadharanMGBroderS & JohnsDG (1988) Factors determining the activity of 2-,3-dideoxynucleosides in suppressing human immunodeficiency virus in vitro. Molecular Pharmacology34: 431–435.
13.
HuangHChopraRVerdineGL & HarrisonSC (1998) Structure of a covalently trapped catalytic complex of HIV-1 reverse transcriptase: Implications for drug resistance. Science282: 1669–1675.
14.
LarderBABloorSKempSDHertogsKDesmetRLMillerVSturmerMStaszewskiSRenJStammersKStuartDI & PauwelsR (1999) A family of insertion mutations between codons 67 and 70 of human immunodeficiency virus type 1 reverse transcriptase confer multinucleoside analog resistance. Antimicrobial Agents & Chemotherapy43: 1961–1967.
15.
LarderBA & KempSD (1989) Multiple mutations in HIV-1 reverse transcriptase confer high-level resistance to zidovudine (ZDV). Science246: 1155–1158.
16.
LittleSJDaarESD'AquilaRTKeiserPHConnickEWhitcombJMHellmanNSPetropoulosCJSuttonLPittJARosenbergESKoupRA & RichmanDD (1999) Reduced antiretroviral drug susceptibility among patients with primary infection. Journal of the American Medical Association282: 1142–1149.
17.
MansourTSJinHWangWHookerEAshmanCCammackNSalomonHBelmonteAR & WainbergMA (1995a) Anti-human immunodeficiency virus and anti-hepatitis B virus activities and toxicities of the enantiomers of 2′-deoxy-3′-oxa-4′-thiocytidine and their 5-fluoro analogues in vitro. Journal of Medicinal Chemistry38: 1–4.
18.
MansourTSJinHWangWDixitDMEvansCATseHLABelleauBGillardJWHookerEAshmanCCammackNSalomonHBelmonteAR & WainbergMA (1995b) Structure—activity relationships among a new class of antiviral heterosubstituted 2′,3′-dideoxynucleoside analogues. Nucleosides & Nucleotides14: 627–635.
19.
RichardNSalomonHRandoRMansourTBowlinTL & WainbergMA (2000) Selection and characterization of human immunodeficiency virus type 1 variants resistant to the (+) and (-) enantiomers of 2>-deoxy-3′-oxa-4′-thio-5-fluorocytidine. Antimicrobial Agents & Chemotherapy44: 1127–1131.
20.
RichardNQuanYSalomonHHsuMBedardJRandoRMansourTBowlinTL & Wainberg (1999) Selection and characterization of HIV-1 variants resistant to the (+) and (-) enantiomers of 2′-deoxy-3′-oxa-4′-thiocytidine (dOTC). Antiviral Therapy4: 171–177.
21.
SalomonHGuZGaoQNagaiKHiscottJ & WainbergMA (1995) Host cell dependence of human immunodeficiency virus type-1 drug resistance profiles and tissue culture selection pattern. Antiviral Chemistry & Chemotherapy6: 222–229.
22.
SarafianosSGDasKClarkADJr.DingJBoyerPLHughesSH & ArnoldE (1999) Lamivudine (3TC) resistance in HIV-1 reverse transcriptase involves steric hindrance with β-branched amino acids. Proceedings of the National Academy of Science, USA96: 10027–10032.
23.
St-ClairMHMartinJLTudor-WilliamsGBachMCVavroCLKingDMKellamPKempSD & LarderBA (1991) Resistance to ddI and sensitivity to AZT induced by a mutation in HIV-1 reverse transcriptase. Science253: 1557–1559.
24.
TaylorDLAhmedPSTymsASWoodLJKellyLAChambersPClarkeJBedardJBowlinTL & RandoRF (2000) Drug resistance and drug combination features of the human immunodeficiency virus inhibitor, BCH-10652 [(+/-)-2′deoxy-3′-oxa-4′ thiocytidine, dOTC]. Antiviral Chemistry & Chemotherapy11: 291–301.
25.
WintersMACooleyKLGirardYALeveeDJHamdanHShaferRWKatzensteinDA & MeriganTC (1998) A six-basepair insert in the reverse transcriptase gene of the human immunodeficiency virus type 1 confers resistance to multiple nucleoside inhibitors. Journal of Clinical Investigation10: 1769–1775.
26.
ZhangDCaliendoAMEronJJDevoreKMKaplanJCHirschMS & D'AquilaRT (1994) Resistance to 2′,3′-dideoxycytidine conferred by a mutation in codon 65 of the human immunodeficiency virus type 1 reverse transcriptase. Antimicrobial Agents & Chemotherapy38: 282–287.
