$16 Stars: 99 first hand, how should i play this with all lowers

[BeattysLuck]

PokerStars No-Limit Hold'em Tourney, Big Blind is t20 (9 handed) Poker-Stars Converter Tool from FlopTurnRiver.com (Format: FlopTurnRiver)

Button (t1500)
SB (t1500)
BB (t1500)
UTG (t1500)
Hero (t1500)
MP1 (t1500)
MP2 (t1500)
MP3 (t1500)
CO (t1500)

Preflop: Hero is UTG+1 with 9, 9.
UTG calls t20, Hero calls t20, MP1 calls t20, MP2 calls t20, 2 folds</font>, Button calls t20, SB completes, BB raises to t80</font>, UTG calls t60, Hero calls t60, MP1 calls t60, MP2 calls t60, Button calls t60, SB calls t60.

Flop: (t560) 5, 3, 4 (7 players)</font>
SB checks, BB bets t140</font>, UTG calls t140, Hero ???

how should i play this?