Truncate labels by using regexp

is there a way to truncate the label, maybe by using regexp in “alias by”?
In the shown query I get a bunch of “labels” and I would like to remove the “-switch-interval” from the labels. For example, actually the labels are shown like:

  • FIRST-switch-interval
  • SECOND-switch-interval
  • MFR-switch-interval

But I would like to see only:

  • MFR