There's a chance that the S&P 500 's latest sell-off could deepen if oil prices don't edge back down, according to JPMorgan Private Bank. In a note to clients on Friday, researchers at the bank said they see a risk that higher oil prices could trigger a "domino effect" in equities, a situation in which selling pressure in stocks intensifies as oil prices remain elevated and losses in the US market spread globally, ultimately hitting economic growth . Brent crude , the international benchmark,