“Your slave is in your hands,” Abram said. “Do with her whatever you think best.” Then Sarai mistreated Hagar; so she fled from her.
Genesis 16:6 (NIV)
When Sarai "mistreated" Hagar, the Egytian slave, the word is עָנָה (ahnah). It means "to afflict.”
So they put slave masters over them to oppress them with forced labor, and they built Pithom and Rameses as store cities for Pharaoh.
Exodus 1:11 (NIV)
It's the same word that describes how the Egyptians treated their Israelite slaves.
And in both cases, God heard the cry of the afflicted.