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: Expression of the PAX3 - FKHR protein in these cells leads to transformation the cells become enlarged , grow tightly packed and in multiple layers , and acquire the ability for anchorage - independent growth .
### Output Text:
Expression of the PAX3 - FKHR protein in these cells leads to transformation the cells become enlarged , grow tightly packed and in multiple layers , and acquire the ability for anchorage - independent growth . 