title: Technetium-99m sestamibi single photon emission computed tomography findings correlated with P-glycoprotein expression, encoded by the multidrug resistance gene-1 messenger ribonucleic acid, in intracranial meningiomas.
abstract: The present study evaluated whether technetium-99m sestamibi (99mTc-MIBI) single photon emission computed tomography (SPECT) characteristics of intracranial meningioma are correlated with the histological malignancy, proliferative potential, and P-glycoprotein (Pgp) expression, encoded by the multidrug resistance gene-1 (MDR-1) messenger ribonucleic acid (mRNA). Twenty-one patients with intracranial meningiomas, including 17 benign and four nonbenign meningiomas, underwent 99mTc-MIBI SPECT imaging at 15 minutes (early) and 3 hours (delayed) after injection. The tumor-to-normal pituitary gland ratio was calculated on both early (ER) and delayed (DR) images. Retention index (RI) was calculated using the following formula: (DR - ER)/ER x 100%. Meningioma specimens were examined by immunohistochemistry using anti-Pgp and MIB-1 monoclonal antibody. MDR-1 mRNA expression was also investigated using reverse transcription-polymerase chain reaction assay. 99mTc-MIBI was highly accumulated and retained in the tumors. 99mTc-MIBI SPECT findings were not related to MIB-1 labeling index. 99mTc-MIBI SPECT RI of the Pgp-positive group (-9.12 +/- 22.27%) was significantly lower than that of the Pgp-negative group (28.79 +/- 22.80%) (p = 0.0016). No significant difference was seen in ER and DR between the positive and negative groups. These results show that 99mTc-MIBI may not be useful for determining proliferative potential and histological malignancy, but could predict anticancer drug resistance related to the expression of MDR-1 mRNA and its gene product Pgp in patients with intracranial meningiomas.
authors.affiliation: Department of Neurological Surgery, Kagawa Medical University, Kagawa. katsuzo@k9.dion.ne.jp
authors.forename: Katsuzo
authors.initials: K
authors.lastname: Kunishio
authors.forename: Kuniaki
authors.initials: K
authors.lastname: Morisaki
authors.forename: Yoshihito
authors.initials: Y
authors.lastname: Matsumoto
authors.forename: Seigo
authors.initials: S
authors.lastname: Nagao
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Nishiyama
mesh_terms: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000235:genetics*; D000328:Adult; D000368:Aged; D001932:Brain Neoplasms; D017931:DNA Primers / Q000235:genetics; D005260:Female; D019450:Genes, MDR / Q000235:genetics*; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008577:Meningeal Neoplasms / Q000175:diagnosis / Q000235:genetics / Q000378:metabolism; D008579:Meningioma / Q000175:diagnosis / Q000235:genetics / Q000378:metabolism; D008875:Middle Aged; D012333:RNA, Messenger / Q000235:genetics*; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017256:Technetium Tc 99m Sestamibi / Q000493:pharmacokinetics; D015899:Tomography, Emission-Computed, Single-Photon
chemical_list: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D017931:DNA Primers; D012333:RNA, Messenger; D019275:Radiopharmaceuticals; D017256:Technetium Tc 99m Sestamibi