Given the task definition and input, reply with output. In this task, you are given a sentence. You are expected to recognize the name of gene or protein. Although there might be several correct answers, you need to write one of them.

Using a luciferase reporter assay , we demonstrated that v - src overexpression in NIH3T3 induced STAT3 - dependent transcriptional activity from the mcl - 1 promoter and increased endogenous Mcl - 1 protein levels .
Mcl - 1