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Updated: May 28, 2026

Performing Data Mining And Integrative Analysis Of Biomarker in Breast Cancer Using Multiple Publicly Accessible Databases
Published on: May 17, 2019
MGMT and PTEN as potential prognostic markers in breast cancer
Julio Cirullo Neto1, Mariana Mari Ikoma, Katia Cândido Carvalho
1Dept Anatomic Pathology/Cancer Hospital A C Camargo, Rua Antônio Prudente, 109, 1st floor, Liberdade, São Paulo, SP, Brazil.
Aim:
To evaluate the prognostic importance of MGMT and PTEN concerning their correlation with other prognostic factors evaluated by immunohistochemistry (IHC) and the molecular phenotype of breast cancers.
Methods:
IHC for estrogen and progesterone receptors, HER2, Ki67, p53, p63, e-cadherin, EGFR, CK5, CK14, MGMT and PTEN was performed on 200 breast tumors. Basal-like and luminal breast carcinomas were defined by the IHC evaluation of these markers. Fluorescent in situ hybridization (FISH) was performed for PTEN and HER2 analysis using the Vysis PTEN and HER2 DNA probe kits (Abbott™). RT-PCR was performed to evaluate gene expressions of MGMT and PTEN in frozen tissue of 59/200 cases.
Results:
147/200 cases were triple-negative (73.5%), 47/147 were basal-like carcinomas (31.9%). 53 cases (26.5%) were luminal-like type A or B. 56 (93.3%) and 46 samples (76.6%) expressed lower levels of MGMT and PTEN mRNA, respectively, compared with normal breast (p<0.001). There was a positive correlation between the IHC results and the RT-PCR values for MGMT and PTEN. Tumors with homozygotic deletion of PTEN expressed little or no mRNA or protein. Positive p53, high Ki67, and basal-like tumors expressed significant lower MGMT and PTEN.
Conclusions:
We hypothesize that MGMT and PTEN expressions have prognostic significance in breast cancer. Also, based on their predictive value of response to therapy, evaluating MGMT and PTEN and learning to interpret their patterns of immunoexpression will undoubtedly lead to a greater understanding of breast cancer and its treatment.