Adding only bottom line border to chart

Hi all!!

I have a chart that has to have only bottom border.. Is it possible???

The avoid this problem you can alternatively answer the another question. This chart is pasted into word as picture by:

 ws.ChartObjects("Chart3").Activate
 ws.ChartObjects("Chart3").CopyPicture xlScreen, xlPicture
 tbl.Cell(10, 1).Range.Paste ' tbl is a table in word 2010

how to add bottom border to the chart there (by excel vba)?? Thanks in advance!!