Signore was born in Harlem, Manhattan, New York City, USA, on 31 July 1912, to Italian parents. At the age of 12, she moved to the Bronx.

Signore worked as an administrative assistant for the Metropolitan Transportation Authority (MTA), a public benefit corporation responsible for public transportation in the New York City metropolitan area. She retired in 1977, aged 65.

On 2 April 2016, at the age of 103, she survived a robbery in her apartment building, where her attacker knocked her to the ground and stole $35, two meals, a magnifying glass, and a pack of bingo cards.

At the age of 107, she received a significant amount of national media coverage for her claim how not getting married played a part in her longevity. Additionally, she attributed her longevity to good home food and lots of fruit and vegetables. Her younger sister was 102 as of July 2019.

In June 2022, she underwent surgery to have her hip surgically repaired after suffering a fall in her bedroom.

Signore currently lives in the Bronx, New York City, USA.