Looping Through And Processing ListBox Items

At the moment I have a listbox and two buttons. The first button will add files from a directory to the listbox, whilst my second button processes a single txt file inside a folder to remove certain words, then save the processed document as a copy.

Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
' Replace common words and all symbols.
Dim wordsToReplace() As String = {" cat ", " hat ", " that ", ", ", ". "}
Using sr As System.IO.StreamReader = New System.IO.StreamReader("C:User est.txt")
' Read the entire file into memory.
[Code] .....

What I am trying to do now, is rather than process documents in a static folder, I want to process the documents that are inside my listbox, and save the new copies back to the list box (repopulate the list box with the processed txt files, I hope that makes sense). What I think I need to do is loop through the listbox and take the file path for each item, process it, then feed these back into my listbox.