-  INCLUSION CRITERIA:

          -  Patients must have histologically confirmed glioblastoma/gliosarcoma, grades II-III
             astrocytoma and oligodendroglioma confirmed by the Laboratory of Pathology, NCI.

          -  Patients must have recurrent disease for which there is a clinical indication for
             resection.

          -  Age greater than or equal to18 years.

          -  Karnofsky greater than or equal to 60%.

          -  Patients must have adequate bone marrow function (WBC greater than or equal to
             3,000/uL ANC greater than or equal to 1,500/mm^3, platelet count of greater than or
             equal to 100,000/mm^3, and hemoglobin greater than or equal to 10 gm/dL), adequate
             liver function (SGOT and bilirubin < 2 times ULN). These tests must be performed
             within 14 days prior to registration. Eligibility level for hemoglobin may be reached
             by transfusion.

          -  Patients must have a serum creatinine of <=1.7 mg/dL. If the serum creatinine is
             greater than 1.7 mg/dl, a 24-hour urine creatinine clearance will be obtained and if
             the result of this study is within normal limits*, the patient would be eligible to
             enroll onto study. This test must be performed within 28 days prior to registration.
             (*Normal Creatinine Clearance Range: Male: 90 - 130 ml/min; Female: 80 - 125 ml/min)

          -  Patients must be in adequate general medical health to safely tolerate a craniotomy.

          -  Tumor tissue blocks or at least 20 unstained slides from a prior diagnosis will be
             requested. H&E to confirm diagnosis must be available. The 20 unstained slides is
             preferred, but not required.

          -  At the time of registration, all subjects must be removed greater than or equal to 28
             days from any investigational agents.

          -  The effects of LB100 on the developing human fetus are unknown. For this reason, women
             of child-bearing potential and men must agree to use adequate contraception (hormonal
             or barrier method of birth control; abstinence) prior to study entry and for the
             duration of study participation. Should a woman become pregnant or suspect she is
             pregnant while she or her partner is participating in this study, she should inform
             her treating physician immediately.

          -  Ability of subject to understand and the willingness to sign a written informed
             consent document indicating that they are aware of the investigational nature of this
             study, and that this is not a therapeutic clinical trial.

        EXCLUSION CRITERIA:

          -  Patients who are receiving any other investigational agents.

          -  Uncontrolled intercurrent illness including, but not limited to, ongoing or active
             infection, symptomatic congestive heart failure, unstable angina pectoris, cardiac
             arrhythmia, or psychiatric illness/social situations that would limit compliance with
             study requirements.

          -  Patients unwilling to undergo craniotomy.

          -  Pregnant women are excluded from this study because the safety of PP2A inhibition on a
             developing fetus has not been established. Because there is an unknown but potential
             risk for adverse events in nursing infants secondary to treatment of the mother with
             LB100, breastfeeding should be discontinued if the mother is treated with LB100.

          -  Patients may not have had prior chemotherapy or biologic therapy in the 4 weeks prior
             to study entry. For patients who have been treated with targeted therapy, 5 half-lives
             of that therapy (or 28 days, whichever is shorter) must have passed prior to
             enrollment in the study.

          -  HIV-positive patients on combination antiretroviral therapy are ineligible because of
             the potential for pharmacokinetic interactions with LB100. Appropriate studies will be
             undertaken in patients receiving combination antiretroviral therapy when indicated.

          -  Patients who are receiving strong CYP450 inducers or inhibitors are ineligible

          -  Recruitment Strategies

        Patients with recurrent disease will be identified at the Outpatient Clinic of the
        Neuro-Oncology Branch, Clinical Center.