There is no regexp in JQL: https://answers.atlassian.com/questions/138055/how-can-i-use-regex-in-a-jql-query-i-cannot-match-strings-that-have-a-specific-ending-in-jql-ex-ing-should-match-running-jogging-etc
What is the meaning of * in a jql Query?, I have different results when using and not using it. But I didn't find any consequence in the results.