No, none. Gregor is the story of life turned inward, looking too deep.
What he found was what all will find, it is a strange place.
Behind the living, is insect survival, something that lives to stay alive.
Gregor has given up on the distractions of life, withdrawn, to look within.
That is fine, in the values of the universe we are bugs.
He found a truth, but missed the truth of bugs going out to dinner, seeing plays, hearing music, do all the things a bug can do.
He is also Kafka, the writer alone, hardly any contact with the world, to write about it.
The cockroach lives, somewhere, eats, and causes those around to become cockroaches.
Where as brother he should be showing her the world, and to the world, his withdrawal takes her to his isolation, and it is the nature of a female roach to reproduce.
Life at it's lowest is accepted, they live where they can, eat what is available, and will reproduce with whoever is around.
A sub plot is that his condition affects others. He has left life, but drags his sister with him.
She did not want to become Mrs. Roach, but roles are put on us by those around.
Alone, locked in his room, he locks her life up too.
Looking too close at life, destroys it's enjoyment for the viewer, and for those around.