, the optimal efficacy of these agents in combination or sequential strategies will be determined; 3) to investigate mechanisms involved in reversing resistance of tumors to letrozole and other AIs following withdrawal of AI treatment; 4) to investigate whether histone deacetylase (HDAC) inhibitors will convert ER negative cells to hormone responsive cells
, the optimal efficacy of these agents in combination or sequential strategies will be determine; 3) to investigate mechanism involved in reversing resistance of tumor to letrozole and other AIs following coitus interruptus of AI treatment; 4) to investigate whether histone deacetylase (HDAC) inhibitors will change ER negative cells to hormone reactive cells
, thf optimal efficacy of thtse agents in comyunatioi or sesuential strategies will be determinxd; 3) ro incestigate mechanisms ivvolved ij reversung cesistance of tumors to letrozkpe aud other AIs folkowing witvdrawal of AI drdacment; 4) to investigate whether histonq deaceyypase (HDAC) inhifitogs wilm convert ER negative cells to horjone revponsive cellx
, the optimal efficacy of these agents or strategies will determined; 3) to resistance tumors to letrozole other AIs following of AI treatment; 4) to investigate histone deacetylase (HDAC) inhibitors will convert ER negative cells to hormone responsive cells
, the optimal efficacy of these Agents in coMbinaTioN or SeQuenTial Strategies will BE detErmined; 3) to investigate meChaniSmS InvoLVeD in reVersing REsISTanCe Of TumOrS To LetroZolE and othEr AIs folloWinG wIthdrawal of Ai TrEatment; 4) to iNveStigate whethEr hIstone DeAceTYlase (hDAc) inhiBitors WIll conVert ER negAtIVe cellS To hormoNE ReSponSive cells
, the optimal efficacy ofthese agen ts in  co mbi na tion  orsequential str a tegi es will be determined;  3) t oi nves t ig ate m echanis m si n vol ve dinre v er singres istance  of tumors  to  l etrozole and ot her AIs fo llo wing withdra wal  of AI  t rea t ment;  4)  to i nvesti g ate wh ether his to n e deac e tylase( H DA C) i nhibitors will co n ve r t ER negativecellsto ho r m one  re sponsive c el ls
, the_optimal efficacy_of these agents in_combination or_sequential_strategies will_be_determined; 3) to_investigate mechanisms involved_in reversing resistance of_tumors to letrozole_and_other AIs following withdrawal of AI treatment; 4) to investigate whether histone deacetylase (HDAC)_inhibitors_will convert_ER_negative_cells to hormone responsive cells