PTEN coordinates G(1) arrest by down-regulating cyclin D1 via its protein phosphatase activity and up-regulating p27 via its lipid phosphatase activity in a breast cancer model.
Inherited or acquired mutations in specific genes involved in the DNA damage response, for example the breast cancer susceptibility genes 1/2 (BRCA1/2), phosphatase and tensin homolog (PTEN) and P53 are associated with various subtypes of breast cancer.
Alleles in PTEN and other breast cancer susceptibility genes would be responsible for approximately 25% of the familial component of breast cancer risk, BRCA1 and BRCA2 being the two major genes responsible for this inherited risk.
Additionally, we summarized breast cancer risk associated with the following genetic factors: breast cancer susceptibility high-penetrance genes (BRCA1, BRCA2, p53, PTEN, ATM, NBS1 or LKB1) and low-penetrance genes such as cytochrome P450 genes (CYP1A1, CYP2D6, CYP19), glutathione S-transferase family (GSTM1, GSTP1), alcohol and one-carbon metabolism genes (ADH1C and MTHFR), DNA repair genes (XRCC1, XRCC3, ERCC4/XPF) and genes encoding cell signaling molecules (PR, ER, TNFalpha or HSP70).
PTEN deletion increased PI(3,4)P<sub>2</sub> levels in a mouse model of prostate cancer, and it inversely correlated with PI(3,4)P<sub>2</sub> levels across several EGF-stimulated prostate and breast cancer lines.
We identified that YAP1 promotes cell growth and inhibits cell apoptosis of BC through the phosphatase and tensin homolog deleted on chromosome 10-AKT signaling pathway, and thus suggest that YAP1 might serve as a new target for inhibiting BC progression.
METABIRC and TCGA breast cancer cohort mRNA expression data analysis revealed that a high expression of the anti‑angiogenesis‑associated genes, THBS2, SERPINF1 and serpin family B member 5 (SERPINB5), and of the tumor suppressor gene, PTEN, was associated with a better overall survival (OS) of breast cancer patients.
Furthermore, introduction of PTEN into human breast carcinoma cells induced apoptotic cell death and inhibited cell growth and tumor formation in nude mice.
Epithelial to mesenchymal transition (EMT) is a process in which epithelial cells lose cell polarity and cell-cell adhesion and gain migratory and invasive properties to become mesenchymal cells that are very vital for development, wound healing and stem cell behavior and contribute pathologically to fibrosis and cancer progression. miR21, a potent regulator of the tumor suppressor gene PTEN, can be silenced to reverse EMT, thereby providing an attractive target for abrogating the malignant behavior of breast cancer.
IPA® enrichment analysis revealed known pathways ('mTOR Signaling', 'PI3K/AKT Signaling' and 'PTEN Signaling') as well as enriched canonical pathways not previously associated with human ovarian follicle development such as 'ErB Signaling' and 'NGF Signaling' in the down-regulated category and 'Regulation of eIF4 and P70S6K Signaling' and 'HER-2 Signaling in Breast Cancer' in the up-regulated group.
Human breast cancer cell lines with or without the expression of BRCA1 and/or PTEN were treated with PARP1 and PI3K inhibitors as single agents and in combination.
A new tumor suppressor gene PTEN/MMAC1 was recently isolated at chromosome 10q23 and found to be inactivated by point mutation or homozygous deletion in glioma, prostate and breast cancer.
In this perspective, glioblastoma U-87 MG and breast cancer MCF7 spheroids were generated to assess the therapeutic prospect of recombinant PTEN protein.
Women diagnosed with breast cancer who carry pathogenic variants in genes with proven associations with breast cancer (BRCA1/2) or highly likely associations (PTEN, PALB2) require additional risk assessment to facilitate treatment decisions that will limit in-breast tumor recurrence and contralateral breast cancer.
A total of 360 paired breast carcinoma and adjacent normal tissue samples from 180 sporadic breast cancer patients were included in the present study and examined for PTEN promoter methylation status by methylation-specific polymerase chain reaction.