property Item.CaptionFormat as CaptionFormatEnum
Specifies how the item's caption is displayed.

TypeDescription
CaptionFormatEnum A CaptionFormatEnum expression  that indicates whether the control uses built-in HTML tags to display the cell's caption.
Use the CaptionFormat property to allow built-in HTML tags in the item's caption. Use the Caption property to specifies the cell's caption. By default, the CaptionFormat property is exText.

The control supports the following HTML tags: 

Also, newer HTML format supports decorative text like follows: