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

### Input Text: CONCLUSIONS : Ischaemic coronary arteriosclerosis with an incidence rate of 16 . 6 % as caused by prolonged CPA therapy is mediated through changes in HDL cholesterol , Apo A - I and Apo A - II pro fi les , other than the well - known hyperglyceridemic effect caused by estrogen .
### Output Text:
CONCLUSIONS : Ischaemic coronary arteriosclerosis with an incidence rate of 16 . 6 % as caused by prolonged <span class="chemical">CPA</span> therapy is mediated through changes in HDL <span class="chemical">cholesterol</span> , Apo A - I and Apo A - II pro fi les , other than the well - known hyperglyceridemic effect caused by <span class="chemical">estrogen</span> . 