Immunohistochemical MSI-screening status and expression of p21, p27 and p53 was assessed in tissue microarrays with tumours from 557 cases of incident CRC in the Malmö Diet and Cancer Study.
Collectively, these results demonstrate an unprecedented connection between p27, Pitx2 and p21 relevant for the regulation of cell cycle progression and cancer and for understanding human pathologies associated with p27 germline mutations.
These findings, overall, suggest that Skp2 may play an important role in ACC development through the down-regulation of p27 and that Skp2 siRNA can be a novel modality of cancer gene therapy for suppression of p27 down-regulation in ACC.
Reduced expression of P27 is associated with advanced stage of cancer and can be used as a biological marker in clinical routine assessment and management of women with advanced ovarian cancer.
Thus, this novel chimeric molecule is more potent and capable of killing a broader spectrum of tumors than the parental p16 and p27 molecules independent of the tumor cell p53 and phenotype and represents a powerful new therapeutic agent for cancer gene therapy.
We previously showed that mitogenic 17-β-estradiol (E2) induces degradation of p27 by the E3 ligase Skp1-Cullin1-F-Box- S phase kinase-associated protein2/cyclin dependent kinase regulatory subunit 1 in primary endometrial epithelial cells and endometrial carcinoma (ECA) cell lines, suggesting a pathogenic mechanism for type I ECA, an E2-induced cancer.
The study aimed at the assessment of expression levels of cyclins D1 and E in surgically removed gastric cancers, including the analysis of this prognostic value parameter, and attempted to determine some correlations between the expression of the examined cyclins and selected histoclinical and molecular parameters such as: patients' age and gender, histological type according to the Lauren classification, cancer stage (TNM), degree of histological malignancy (G) and level of expression of the cell-cycle regulatory genes protein products--P53, P21, P27.
Moreover, we found some gene functions, such as Fused in Sarcoma (FUS, which may be part of transcriptional misregulation in cancer) and p27 (which we expect will become a member viral carcinogenesis), that can be used to complete the related pathways.
Down-regulation of p27 in cancer cells was frequently observed in adenocarcinoma (AC) and squamous cell carcinoma (SCC), but not in small cell carcinoma (SmCC).
H. pylori infected wild-type (WT) mice do not develop cancer, but mice lacking the tumor suppressor p27 do so, thus providing an experimental model of H. pylori-induced cancer.
Collectively, our findings support the hypothesis that Cks1 supports hepatocarcinogenesis by NF-κB-mediated regulation of IL-8 expression, broadening the function of Cks1 in cancer beyond its role as a Skp2 cofactor in p27 ubiquitination.
Therefore, knockdown of Skp2 expression by RNAi inhibits breast cancer cell growth and enhances the effect of epirubicin. siRNA-mediated gene silencing of Skp2 could be a novel cancer gene therapy for the suppression of p27 down regulation.
When the role of SCF<sup>Skp2/Cks1</sup>-mediated p27 ubiquitination in cancer was specifically tested by p27Thr187-to-Ala knockin (p27T187A KI), it was found dispensable for Kras<sup>G12D</sup>-induced lung tumorigenesis but essential for Rb1-deficient pituitary tumorigenesis.
Further studies revealed that the compounds were able to induce cancer cell differentiation and concomitantly downregulate cyclin D1 expression with upregulation of p27 levels, consistent with cell cycle arrest at the G1 phase.
We show for the first time that SmgGDS promotes proliferation of pancreatic cancer cells, and we demonstrate that SmgGDS-558 plays a greater role than SmgGDS-607 in cell cycle progression as well as promoting cyclin D1 and suppressing p27 expression in multiple types of cancer.