Inclusion Criteria

DISEASE CHARACTERISTICS:

- Diagnosis of 1 of the following hematologic malignancies:

- Chronic myelogenous leukemia meeting 1 of the following criteria:

- In accelerated phase, defined by the presence of ≥ 1 of the following:

- At least 15% but < 30% blasts in peripheral blood and/or bone marrow

- At least 30% blasts plus promyelocytes in peripheral blood or bone
marrow (providing that < 30% blasts are present in bone marrow)

- At least 20% basophils in peripheral blood

- Platelet count < 100,000/mm³ (unrelated to therapy) OR platelet count
> 100,000/mm³ and unresponsive to therapy

- Cytogenetic evidence of clonal evolution

- Increasing spleen size and increasing WBC count and unresponsive to
therapy

- In blastic phase (blast crisis), defined by the presence of ≥ 1 of the
following:

- At least 30% blasts in peripheral blood and/or bone marrow

- Extramedullary infiltrates of leukemic cells (other than liver or
spleen involvement)

- Philadelphia chromosome-positive acute lymphoblastic leukemia meeting any of the
following criteria:

- Newly diagnosed or relapsed disease

- Previously treated with chemotherapy, stem cell transplantation, or
tyrosine kinase inhibitors (TKIs)

- No active CNS involvement

PATIENT CHARACTERISTICS:

- ECOG performance status 0-2

- Total bilirubin < 2.0 times upper limit of normal (ULN)

- AST and ALT ≤ 2.5 times ULN

- Serum sodium, potassium, magnesium, phosphate, and calcium ≥ lower limit of normal

- Not pregnant or nursing

- Negative pregnancy test

- Fertile patients must use effective contraception during and for ≥ 4 weeks after
discontinuation of study drug

- Able to take oral medication

- No active post-transplantation-related infections (e.g., fungal or viral infection)

- No active acute graft-versus-host disease (GVHD) of any grade

- No chronic GVHD (other than mild skin, oral, or ocular GVHD not requiring systemic
immunosuppression)

- No other malignancy that required radiotherapy or systemic treatment within the past
5 years

- No concurrent medical condition that may increase the risk of toxicity, including
pleural or pericardial effusion of any grade

- No cardiac conditions, including any of the following:

- Uncontrolled angina, congestive heart failure, or myocardial infarction within
the past 6 months

- Diagnosed congenital long QT syndrome

- History of clinically significant ventricular arrhythmias (e.g., ventricular
tachycardia, ventricular fibrillation, or Torsades de pointes)

- Prolonged QTc interval (i.e., QTc > 450 msec) on baseline EKG

- No hypokalemia or hypomagnesemia that cannot be corrected prior to dasatinib
administration

- No history of significant bleeding disorder unrelated to cancer, including any of the
following:

- Diagnosed congenital bleeding disorder (e.g., von Willebrand's disease)

- Acquired bleeding disorder diagnosed within the past year (e.g., acquired
anti-factor VIII antibodies)

- Ongoing or recent (i.e., within the past 3 months) significant gastrointestinal
bleeding

- No prisoners or individuals who are compulsorily detained (i.e., involuntarily
incarcerated) for treatment of either a psychiatric or physical (e.g., infectious)
illness

PRIOR CONCURRENT THERAPY:

- See Disease Characteristics

- Recovered from prior therapy

- No prior HDAC inhibitors or compounds with HDAC inhibitor-like activity (e.g.,
valproic acid) as anti-tumor therapy

- Prior valproic acid for the treatment of seizures allowed provided it was not
given within the past 30 days

- Prior allogeneic stem cell transplantation allowed

- More than 4 weeks since prior chemotherapy other than TKI (6 weeks for nitrosoureas
and mitomycin)

- More than 2 weeks since prior radiotherapy

- At least 7 days since prior and no concurrent Category I drugs that are generally
accepted to have a risk of causing Torsades de pointes, including any of the
following:

- Quinidine, procainamide, or disopyramide

- Amiodarone, sotalol, ibutilide, or dofetilide

- Erythromycin or clarithromycin

- Chlorpromazine, haloperidol, mesoridazine, thioridazine, or pimozide

- Cisapride, bepridil, droperidol, methadone, arsenic, chloroquine, domperidone,
halofantrine, levomethadyl, pentamidine, sparfloxacin, or lidoflazine

- At least 7 days since prior and no concurrent medications that directly and durably
inhibit platelet function, including any of the following:

- Aspirin or aspirin-containing combinations, clopidogrel, or dipyridamole

- Tirofiban, epoprostenol, eptifibatide, cilostazol, abciximab, ticlopidine, or
cilostazol

- At least 5 days since prior and no concurrent St. John's wort

- No IV bisphosphonates during the first 8 weeks of dasatinib therapy