In the sentence extracted from biomedical literature, identify all the disease entities. The required answer format is the same sentence with HTML <span> tags to mark up specific entities. 
### Entity Markup Guides:
Use <span class="disease"> to denote a disease.

### Input Text: PTEN , a putative protein tyrosine phosphatase gene mutated in human brain , breast , and prostate cancer .
### Output Text:
PTEN , a putative protein tyrosine phosphatase gene mutated in human <span class="disease">brain , breast , and prostate cancer</span> . 