Display labels in line with the edge when using Graphviz

I am using Graphviz 2.30. Horizontal positioning for labels works out, but in a few cases, a modified angle would be desired.

For instance, I tried various values for angle here but without any effect:

ABB -> ABACUS[label="applied", fontname="Arial", fontsize=15, labelangle=110];

How can I display labels in line with (i.e. parallel to) the edge when using a Graphviz digraph.

The entire digraph will not be posted due to an NDA. In addition, the rotation will be applied only to a few labels.

I have read similar threads like this or another (or a thread about alignment for instance) but without any help regarding my issue.

Using dot2latex allows you to specify lblstyle attribute. The value of lblstyle is used by PGF/TikZ in pdf generation.

One can specify parallel labels like this:

digraph G {
    edge [lblstyle="above, sloped"];
    a -> b [label="ab"];
    b -> c [label="bc"];
    c -> a [label="ca"];
}

To generate the pdf

$ dot2tex --tikzedgelabel file.dot > file.tex
$ pdflatex file.tex

The result is

Edit: another answer found an option that now exists to align text with edges.

Your best option may be to export the graph as an SVG and use Illustrator or Inkscape to fine-tune it. This is only practical when producing a few graphs.

I frequently have to tweak the output from Graphviz and Gephi; they give me a good starting point though.