Inclusion Criteria:

1. Unresectable, recurrent, or metastatic histologically-confirmed soft tissue or bone sarcoma of one of the following subtypes:

   • Leiomyosarcoma --* NO LONGER ELIGIBLE*
   • Liposarcoma--* NO LONGER ELIGIBLE*
   • Malignant fibrous histiocytoma (MFH)/pleomorphic undifferentiated sarcoma
   • Rhabdomyosarcoma
   • Malignant peripheral nerve sheath tumor (MPNST)
   • Osteosarcoma (skeletal or extraosseous)
   • Chondrosarcoma
   • Ewing's
   • Alveolar soft part sarcoma
   • Chordoma
   • Epithelioid sarcoma
   • Giant cell tumor of bone
   • Hemangiopericytoma/solitary fibrous tumor
   • Gastrointestinal Stromal Tumor (GIST)
2. Documentation that subjects with leiomyosarcoma, liposarcoma, osteosarcoma, Ewing's, MPNST, rhabdomyosarcoma or MFH have received, not been eligible for or refused at least one prior chemotherapy regimen before participation in the dasatinib study. Subjects with GIST must have received or been intolerant to imatinib; prior treatment with other agents including sunitinib is not required.Neoadjuvant/adjuvant chemotherapy qualifies as prior therapy.
3. Subjects must have unidimensionally measurable lesion(s) either by x-ray, computed tomography (CT), magnetic resonance imaging (MRI) or physical examination documented within 30 days prior to registration.
4. Prior radiation will be allowed. More than two weeks should have elapsed since the administration of the last fraction of radiation therapy, and subjects must have recovered from grade 2 or higher associated toxicities. Measurable lesions, which are selected as target lesions, must be outside previously radiated fields or have documented progression no sooner than 6 weeks after completion of radiation.
5. More than 2 weeks must have elapsed since the subject has received any prior systemic chemotherapy (6 weeks for mitomycin C), and the patient should have recovered from toxicities to the baseline prior to the last course of chemotherapy.
6. Adequate hematologic function within 14 days prior to registration.
7. PT (or INR) and PTT ≤ 1.5 times the institutional ULN within 14 days prior to registration.
8. Serum creatinine ≤ 2.0 times the institutional ULN within 14 days prior to registration.
9. Serum magnesium, potassium and adjusted (or ionized) calcium ≥ the institutional LLN. (Supplementation of electrolytes prior to screening is allowed).
10. Left ventricular ejection fraction ≥ 45% measured by echocardiogram or multiple gated acquisition (MUGA) within 30 days prior to registration (but must be performed after the last dose of an anthracycline) for subjects who have received an anthracycline (e.g. doxorubicin, epirubicin) or have a medical history of cardiac disease. The measurement of left ventricular ejection fraction is not required of subjects whom have not received cardiotoxic chemotherapy (e.g. anthracycline) and do not have a medical history of cardiac disease.
11. Sexually active women and men of childbearing potential must agree to use an effective method of birth control during the course of the study and for up to 3 months following the last dose of the study drug, in a manner such that risk of pregnancy is minimized. Surgical sterilization, intrauterine device or barrier method (e.g. condom and/or diaphragm with spermicidal agents) are acceptable forms of birth control.
12. Women of childbearing potential must have a negative pregnancy test (urine or serum) within 7 days prior to treatment. A pregnancy test is not required for registration. Women who have not menstruated for more than 2 years will be considered postmenopausal, thus not of childbearing potential.
13. ECOG performance score 0, 1 or 2.
14. Weight ≥ 50 kg because there is limited experience with dasatinib in subjects weighing less than 50 kg.
15. ≥13 years of age Minors will be required to sign an assent document prior to treatment.
16. Subjects must be able to swallow whole tablets.
17. Subjects must be informed of the investigational nature of the study and provide written, informed consent and authorization to release protected health information using a document(s) approved by the investigator's institution.
18. A paraffin block, either from a previous surgery or recent biopsy, should be available for correlative studies. If a block of tumor is not available, at least 8 unstained slides of tumor sample, 1 H&E and three (3) 15 micron-thick sections in an eppendorf tube for DNA extraction from a representative portion of the sarcoma may be substituted after discussion with and approval from the study Principal Investigator.

Exclusion Criteria:

1. Subjects who are curable by conventional multidisciplinary management.
2. Subjects with symptomatic central nervous system metastasis.
3. Women who are pregnant or nursing/breastfeeding.

4. History of significant bleeding disorder unrelated to cancer, including:

   • Diagnosed congenital bleeding disorders (e.g., von Willebrand's disease)
   • Diagnosed acquired bleeding disorder within one year (e.g., acquired anti-factor VIII antibodies)
5. Subjects currently taking medications that inhibit platelet function (i.e., aspirin, dipyridamole, epoprostenol, eptifibatide, clopidogrel, cilostazol, abciximab, ticlopidine, and any non-steroidal anti-inflammatory drug) because of a potential increased risk of bleeding from dasatinib.
6. Subjects currently taking anticoagulants (warfarin, heparin/low molecular weight heparin [e.g., danaparoid, dalteparin, tinzaparin, enoxaparin]) because of a potential increased risk of bleeding from dasatinib.
7. Diagnosis of unstable angina or myocardial infarction within 6 months of study entry.

8. Subjects currently taking one or more of the following drugs that are generally accepted to have a risk of causing Torsades de Pointes:

   • Quinidine, procainamide, disopyramide
   • Amiodarone, sotalol, ibutilide, dofetilide
   • Erythromycins, clarithromycin
   • Chlorpromazine, haloperidol, mesoridazine, thioridazine, pimozide
   • Cisapride, bepridil, droperidol, methadone, arsenic, chloroquine, domperidone, halofantrine, levomethadyl, pentamidine, sparfloxacin, lidoflazine.
9. Diagnosed or suspected congenital long QT syndrome.
10. Prolonged QTc interval on pre-entry electrocardiogram (> 450 msec) within 30 days prior to study registration.
11. Subjects unable or unwilling to suspend treatment with bisphosphonates for at least the first 8 weeks of treatment with study drug because of the risk of hypocalcemia caused by dasatinib.