Inclusion Criteria:

- Patients must have histologically or cytologically confirmed brain tumors of the
following types: Group 1: malignant brain tumors (glioblastoma multiforme, anaplastic
gliomas, brain metastases, and other malignant brain tumors); or Group 2: low grade
brain tumors (low grade gliomas, meningiomas, and other low grade brain tumors)

- All stages and grades of brain tumors are eligible

- Patients must have an ECOG performance status of 0-2

- Patients must have agreed to be treated with fractionated, external beam radiation
treatment (EBRT) with either curative or palliative intent (the length of the
radiation course must at least be ten fractions)

- Patients must have agreed to have CT and MR imaging for purposes of radiation
treatment planning, radiation treatment monitoring, and/or radiation treatment
evaluation

- Patients must have measurable disease and/or relevant anatomic features using
Magnetic Resonance Imaging

- Prior therapies (cytotoxic, surgery, and radiation) are acceptable

- Use of steroids is acceptable when indicated

- Patients must be able to understand and willingly give informed written consent to
participate

- Women of childbearing potential must not be pregnant or nursing and must use
medically appropriate contraception if sexually active

- Patients must have a life expectancy of greater than 3 months

- Patients must be willing to comply with an oral treatment regimen and be able to
swallow oral study tablets

Exclusion Criteria:

- History of allergic reactions to pioglitazone or any other member of the
thiazolidinedione family

- Current diagnosis of diabetes as defined by fasting blood sugar > 125, treatment with
anti-diabetic medications, or history of diabetes

- Patients who take insulin

- Patients who have NYHA class III or IV heart failure

- Patients who have elevated transaminases (AST or ALT > 2.5 times normal limit)

- Patients who have significantly impaired renal function (creatinine >= 1.5)

- Patients who are significantly anemic (hematocrit < 33% in men, or < 30% in women)

- Patients who have symptomatic edema (>= grade 2)

- Patients who are on medications that have been shown to have a drug interaction with
pioglitazone: atorvastatin (doses > 80 mg/day), systemic anti-fungals, medications
with significant CYP 3A4 inhibiting properties

- 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

- Pregnant women are excluded from this study if their pregnancy precludes radiation
treatment because ionizing radiation used in radiation treatment is an agent with
known potential for teratogenic or abortifacient effects

- Patients with psychiatric or social illnesses that may impair compliance with the
trial requirements