How to show two lines of text in detailTextLabel of UITableViewCell?

Question

I have a detailTextLabel that's about two lines long, but it only shows one. I want to make sure I have two lines to almost show the whole message.

This is what I've tried so far:

override func layoutSubviews() {
    super.layoutSubviews()

    textLabel?.frame = CGRectMake(50, textLabel!.frame.origin.y - 8, textLabel!.frame.width, textLabel!.frame.height)
    textLabel?.font = UIFont(name: "GillSans-SemiBold", size: 16)

    detailTextLabel?.frame = CGRectMake(50, detailTextLabel!.frame.origin.y - 10, detailTextLabel!.frame.width, detailTextLabel!.frame.height + 10)
    detailTextLabel?.lineBreakMode = .ByWordWrapping
    detailTextLabel?.numberOfLines = 2
    detailTextLabel?.font = UIFont(name: "GillSans-SemiBold", size: 14)
    detailTextLabel?.allowsDefaultTighteningForTruncation = true
    detailTextLabel?.textColor = UIColor.darkGrayColor()
}