This is a dose escalation study of bortezomib. Patients are assigned to 1 of 2 treatment groups. GROUP I (Dose levels 1-2): Patients receive oral midostaurin twice daily on days 1-14 and bortezomib IV on days 1, 4, 8, and 11. Treatment repeats every 28 days for up to 3 courses in the absence of disease progression or unacceptable toxicity. GROUP II (Dose levels 3-6): Patients receive mitoxantrone hydrochloride IV over 10 minutes, etoposide IV over 1 hour, and cytarabine IV over 6 hours on days 1-6. Patients also receive oral midostaurin twice daily on days 8-21 and bortezomib IV on days 8, 11, 15, and 18. Treatment continues in the absence of disease progression or unacceptable toxicity.