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: However , a 38 % remission rate has been recently reported in refractory MCL treated with temsirolimus , a mTOR inhibitor . Here we had the opportunity to study a case of refractory MCL who had tumor regression two months after temsirolimus treatment , and a progression - free survival of 10 months .
### Output Text:
However , a 38 % remission rate has been recently reported in refractory MCL treated with <span class="chemical">temsirolimus</span> , a mTOR inhibitor . Here we had the opportunity to study a case of refractory MCL who had tumor regression two months after <span class="chemical">temsirolimus</span> treatment , and a progression - free survival of 10 months . 