Overexpression of cyclin B1 in gastric cancer and its clinicopathological significance: an immunohistological study

Abstract

These findings suggested that cyclin B1 protein overexpression is closely associated with less aggressive tumor behavior. Therefore, G2/M cyclin alternatives and the possible role of cyclins in cancer development warrants further attention.

Alteration of subcellular and cellular expression patterns of cyclin B1 in renal cell carcinoma is significantly related to clinical progression and survival of patients

“…47,48 Interestingly, we found the expression of cyclin B1 to be predominantly retained in the cytoplasm of peritumoral, histologically benign renal parenchyma, thus indicating the status of mitotically blocked cells. The finding of peritumoral cytoplasmic expression of cyclin B1 in normal colonic 21 and gastric 25 mucosa cells has also been previously described. In addition to the localization of cyclin B1 within histologically benign epithelial cells, low or missing proliferative activity of peritumoral renal cells has already been described using detection of the Ki67 antigen, 49 thus also supporting the hypothesis that peritumoral cells exhibit increased cytoplasmic cyclin B1 levels due to a mitotic block of cells rather than to an increased proliferative activity.…”

“…With similar high frequency, overexpression of cyclin B1 has been detected in adenocarcinomas of the colon. 21,38 In contrast, several human malignancies including prostate, 23 gastric, 25 lung, 39 tongue 28 and esophageal 27 cancer were frequently found to demonstrate lower immunohistochemical positivity for cyclin B1. Moreover, in several cancers high levels of cyclin B1 protein were found to be significantly associated with cancer progression, thus indicating dysregulation of cyclin B1 as a common phenomenon occurring during cancer development.…”

“…6,25 No correlation with clinicopathological variables or the patients' long-term survival was observed in studies investigating colon, 21 gastric 45 and prostate 46 cancers. Therefore, organ specificity or heterogeneity of the expression of cyclin B1 may specifically affect tumor progression and clinical prognosis.…”

“…[18][19][20] So far, increased levels of cyclin B1 protein were observed in colon, 21 breast, 22 prostate, 23 oral cavity 24 and gastric cancer. 25 Furthermore, for squamous cell carcinomas of the lung 26 as well as esophageal, 27 tongue 28 and small cell lung cancer, 29 expression of cyclin B1 correlated with increased biological aggressiveness and decreased long-term survival of affected patients. To date, no information on cyclin B1 expression in renal cell cancer is available.…”

Alterations of ubiquitin ligases in human cancer and their association with the natural history of the tumor

“…This ligase controls the degradation of Cyclin B1 (Toby et al, 2003), projecting elevated levels of this cyclin in CCNB1IP1-deficient cells. Overexpression of Cyclin B1, in turn, has been reported in various human tumors, and it is a predictor of poor prognosis (Wang et al, 1997;Soria et al, 2000;Dong et al, 2002;Hassan et al, 2002;Yasuda et al, 2002). High levels of Cyclin B1 might cause misregulation of the Cyclin B1/Cdk1 complex, allowing escape from the G2-M checkpoint induced by DNA damage (Lobrich and Jeggo, 2007).…”