What specific virus was Henrietta Lack infected by ? How did her cancer start ? Look up .. What is a tumor suppressor gene ?

Henrietta was infected by HPV. Her cancer started when "HPV inserted its DNA into the long arm of her eleventh chromosome and essentially turned off her p53 tumor suppressor." 

The definition of tumor suppressor gene is not included in the text. 

Genes in the body that can suppress or block the development of cancer. A tumor suppressor gene directs the production of a protein that is part of the system that regulates cell division. The tumor suppressor protein plays a role in keeping cell division in check.