DrugBank contains drug therapies which are linked to disease indications, and each compound record has additional information about targets, mechanism of action, etc..
For example, the following search link returns approved drug indications for a DrugBank search for "brain cancer":
The answer is very complex because "brain cancer" is not just one type of cancer, but many types. Even before advances in sequencing, it was very clear from tissue biopsy that brain tumors were very diverse, depending on the cell of origin, for example, astrocytoma versus oligodendroglioma versus glioblastoma, and even the location in the brain.
More recently, with the advent of DNA sequencing technologies, it is becoming clear that there is a molecular classification of brain tumors that define subsets based on mutations.
Unfortunately, most clinical treatment is still not based on the mutation, although research is heading in this direction with personalized medicine.
In my field of glioblastoma, other drugs used clinically would be temozolomide and vincristine.
There are many, more than I can list. They depend on the age of onset, whether the cancer is aggressive or low grade, and where in the brain the tumor arises. I'm not sure what your university access is like to journals, but here are a few papers. I placed the link to the pubmed abstracts.
Hope you are doing well. You first have to decide whether you will be working on primary or secondary brain tumors? Also visit the "http://www.genome.jp/kegg/disease/cancer.html" and check the pathway to select your genes. I hope this would help.