Inclusion Criteria:

          -  A diagnosis of dedifferentiated liposarcoma confirmed at MSKCC.

          -  Metastatic and/or locally advanced or locally recurrent disease that is not surgically
             resectable.

          -  All patients must have measurable disease as defined by RECIST 1.1. Patients must also
             have evidence of disease progression by RECIST 1.1 within 6 months of first dose of
             study drug.

          -  Any number of prior therapies (including none) is permitted. The last dose of systemic
             therapy (include targeted therapies) must have been given at least 2 4 weeks prior to
             initiation of therapy. Patients receiving BCNU or mitomycin C must have received their
             last dose of such therapy at least 6 weeks prior to initiation of therapy.

          -  Patients with brain metastasis that have been treated with definitive surgery or
             radiation and have been clinically stable for 3 months are eligible.

          -  Age ≥ 18 years.

          -  ECOG performance status 0 or 1

          -  Adequate organ and marrow function as defined below (ULN indicates institutional upper
             limit of normal):

          -  Absolute neutrophil count ≥ 1.510^9/L

          -  Hemoglobin ≥ 8.0 g/dL

          -  WBC ≥ 3.0 x 10^9/L

          -  Platelets ≥ 100 x 10^9/L

          -  Total bilirubin ≤ 1.5 x ULN except for patients with known Gilbert syndrome

          -  AST(SGOT)/ALT(SGPT) ≤ 3 x institutional ULN

          -  Creatinine ≤ 1.5 x ULN or Creatinine Clearance > 50 mL/min (calculated by
             Cockcroft-Gault method)

          -  Patients must not have current evidence of another malignancy that requires treatment.

          -  Women of child-bearing potential and men must agree to use adequate contraception
             (hormonal or barrier method of birth control; abstinence). Women must not breast feed
             while on study.

          -  Ability to understand and the willingness to sign a written informed consent document.

          -  Ability to swallow capsules

        Exclusion Criteria:

          -  Patients who have not recovered from adverse events of prior therapy to ≤ NCI
             CTCAEv4.0 Grade 1.

          -  Patients receiving any other investigational agents.

          -  Patients who have received prior treatment with a selective CDK4 inhibitor

          -  Uncontrolled intercurrent illness including, but not limited to, known ongoing or
             active infection, including HIV, active hepatitis B or C, symptomatic congestive heart
             failure, unstable angina pectoris, cardiac arrhythmia (specifically, atrial
             fibrillation or ventricular dysrhythmias except ventricular premature contractions),
             or psychiatric illness/social situations that would limit compliance with study
             requirements.

          -  Pregnant women and women who are breast-feeding.