Geminin expression in small lung adenocarcinomas: Implication of prognostic significance

Evaluation of NUF2 and GMNN Expression in Prostate Cancer: Potential Biomarkers for Prostate Cancer Screening

BACKGROUND

Prostate cancer (PC) is one of the most abundant cancers among men, and In Iran, has been responsible for 6% of all deaths from cancer in men. NUF2 and GMNN genes are considered as loci of susceptibility to tumorigenesis in humans. Alterations in expression of these genes have been reported in various malignancies. The aim of our study was to test whether different NUF2 and GMNN expression levels are associated with PC incidence and hence, might be considered as new molecular tools for PC screening.

METHODS

Biopsy samples from 40 PC patients and 41 healthy Iranian men were used to determine the relative gene expression. After RNA extraction and cDNA synthesis, samples were analyzed using TaqMan Quantitative Real time PCR. Patients' background information, included smoking habits and family histories of PC, were recorded. Stages and grades of their PC were classified by the TNM tumor, node, metastasis (TMN) staging system based on standard guidelines.

RESULTS

NUF2 expression did not significantly differ between the groups, while GMNN expression was significantly greater in the PC specimens than in the controls.

CONCLUSION

Regarding the significant role of GMNN in various tumor phenotypes, and its importance in PC progression, the alteration in GMNN expression in PC samples vs. controls indicate that the genetic profiling of this cancer might be considered to personalize therapy for each patient in the future.

Regulation of geminin by neuropeptide Y in vascular smooth muscle cell proliferation : A current review

Geminin, a key regulator of DNA replication licensing in the cell cycle, plays an essential role in determining the fate of cells via suppression of cell proliferation and cellular differentiation. Neuropeptide Y (NPY) intensifies the proliferation of vascular smooth muscle cells (VSMCs) directly by binding with Y1 receptors. In vitro experiments have shown that stimulation of NPY on VSMCs via regulation of geminin is a double-edged sword. Given that the proliferation and the phenotypic transformation of VSMCs increase the risk for progression of atherosclerosis, we focus on the role of geminin interference in determining the fate of VSMCs. Furthermore, we discuss the therapeutic potential of peripheral neurotransmitter interference, thus pointing toward future research directions in the treatment of atherosclerosis.

Expression of Minichromosome Maintenance Proteins (MCM) and Cancer Prognosis: A meta-analysis

Minichromosome maintenance proteins (MCM) played a critical role in replication and cell cycle progression. However, their prognostic roles in cancer remain controversial. Therefore, we performed a meta-analysis to investigate the prognostic value of MCMs in cancers. Totally 31 eligible articles with 7653 cancer patients were included in this meta-analysis. We evaluated the relationship between MCMs expression and overall survival (OS) in various cancer patients by using pooled hazard ratios (HRs) and risk ratios (RRs) with 95% confidence intervals (CIs). The meta-analysis showed that carriers with high expression of MCM5 and MCM7 were significantly associated with short OS for pooled HR (HR=1.04, 95% CI=1.01-1.08, P=0.020, HR=1.78, 95% CI=1.04-3.02, P=0.035, respectively). For pooled RR, individuals with increased MCM2 and MCM7 expression were significantly correlated with poor OS (RR=2.30, 95% CI=1.14-4.63, P=0.019; RR=3.52, 95% CI=2.01-6.18, P<0.001, respectively). The findings suggest that high expression of MCM2, MCM5 and MCM7 might serve as predictive biomarkers for poor prognosis in cancers.

Expression of geminin, p16, and Ki67 in cervical intraepithelial neoplasm and normal tissues

Geminin is a protein involved in cell cycle progression. We aimed to evaluate the diagnostic value of geminin expression in cervical intraepithelial neoplasm (CIN).The expression of geminin, p16, and Ki67 was examined in 95 samples, including CIN1 (n = 45), CIN2/3 (n = 40), and normal cervical tissues (n = 10) by immunohistochemistry. The correlation between geminin or p16 expression and human papillomavirus (HPV) status was also evaluated.Geminin expression was negative in all normal tissues and expressed in 13.3% of CIN1 and 90.0% of CIN2/3. P16 expression was demonstrated in 24.4% of CIN1 and 87.5% of CIN2/3. The corresponding Ki67 expression was 35.6% and 95.0%. The specificity of geminin for differentiating between CIN1 and CIN2/3 was 86.7%, while for p16 and Ki67 the corresponding values were 75.6% and 64.4%. The sensitivity of geminin, p16, and Ki67 was 90.0%, 87.5%, and 95.0%, respectively. The positive predictive value (PPV) and accuracy of geminin were higher than p16 and Ki67. In addition, geminin expression showed a weak correlation with HPV status, but there was no association between p16 expression and HPV status.These results suggested that geminin had a high degree of sensitivity and specificity in determining CIN2/3. In addition to p16 and Ki67, geminin might be used as a new biomarker to distinguish between CIN1 and CIN2/3.

Geminin a multi task protein involved in cancer pathophysiology and developmental process: A review

DNA replicates in a timely manner with each cell division. Multiple proteins and factors are involved in the initiation of DNA replication including a dynamic interaction between Cdc10-dependent transcript (Cdt1) and Geminin (GMNN). A conformational change between GMNN-Cdt1 heterotrimer and heterohexamer complex is responsible for licensing or inhibition of the DNA replication. This molecular switch ensures a faithful DNA replication during each S phase of cell cycle. GMNN inhibits Cdt1-mediated minichromosome maintenance helicases (MCM) loading onto the chromatin-bound origin recognition complex (ORC) which results in the inhibition of pre-replication complex assembly. GMNN modulates DNA replication by direct binding to Cdt1, and thereby alters its stability and activity. GMNN is involved in various stages of development such as pre-implantation, germ layer formation, cell commitment and specification, maintenance of genome integrity at mid blastula transition, epithelial to mesenchymal transition during gastrulation, neural development, organogenesis and axis patterning. GMNN interacts with different proteins resulting in enhanced hematopoietic stem cell activity thereby activating the development-associated genes' transcription. GMNN expression is also associated with cancer pathophysiology and development. In this review we discussed the structure and function of GMNN in detail. Inhibitors of GMNN and their role in DNA replication, repair, cell cycle and apoptosis are reviewed. Further, we also discussed the role of GMNN in virus infected host cells.

MCM4 and MCM7, potential novel proliferation markers, significantly correlated with Ki-67, Bmi1, and cyclin E expression in esophageal adenocarcinoma, squamous cell carcinoma, and precancerous lesions

Minichromosomal maintenance (MCM) proteins are participants of DNA replication and may represent more accurate markers in determining the proliferative fraction within a tumor than proliferative marker Ki-67. Our study investigated the correlation between MCM4 and MCM7 expression and Ki-67, Bmi1, and cyclin E expression in esophageal adenocarcinoma, squamous cell carcinoma, and precancerous lesions. MCM4 and MCM7 expression had similar distribution as Ki-67 and Bmi1 expression in esophageal carcinoma and pre-cancerous lesions. The mean percentage of MCM4, MCM7, and Ki-67 expression increased from squamous epithelium (5.5%, 7.3%, and 5.9%, respectively), to columnar cell metaplasia (11.2, 13.5%, and 3.4%), Barrett's esophagus (27.7%, 35.3%, and 8.3%), low-grade dysplasia (42.6%, 52.2%, and 12.9%), high-grade dysplasia (63.2%, 77.7%, and 29.6%), adenocarcinoma (61.3%, 75.5%, and 24.5%), and squamous cell carcinoma (74.1, 85.4%, and 36.3%). The percentages of MCM4 and MCM7 expression were significantly higher than Ki-67 expression. Using univariate analysis we found a high percentage of MCM4 expression (>70%) to be significantly associated with lymph node metastasis and shorter survival in the adenocarcinoma group. We also demonstrated the percentage of MCM4 and MCM7 expression to be significantly correlated with Ki-67, Bmi1, and cyclin E expression in esophageal carcinoma and precancerous lesions. MCM4 and MCM7 may serve as more sensitive proliferative markers for the evaluation of esophageal lesions.

Expression of proliferation markers Ki67, cyclin A, geminin and aurora-kinase A in primary breast carcinomas and corresponding distant metastases

Aims

To assess the expression of the following cell cycle regulatory proteins in primary metastatic breast carcinomas (MBCs) and on availability in matched distant metastases (DMs): Ki67, cyclin A, geminin and aurora-kinase A (aurkA); and to compare the expression of these markers in early MBC (EMBC) and late MBC separated into groups according to median time point on metastatic event occurred (28 months).

Methods

The expression of the above mentioned markers was analysed in a total of 47 primary MBCs and 59 DMs (out of which 37 were pairs) by immunohistochemistry. Fourteen breast carcinomas with no relapse over a 10-year follow-up period were utilised as control cases (CBC).

Results

Among the MBCs, 22 metastasised to the bone, 4 to the lung and 21 to the central nervous system (CNS). Geminin (p<0.001) and Ki67 (p=0.001) were increased in the MBCs while aurkA and cyclin A showed no difference when compared with CBCs. There were no differences between aurkA, cyclin A and geminin expression in MBCs and DMs in general. Expression of Ki67 was, however, elevated (p=0.027) in DMs. In CNS metastases all markers showed elevated expression as compared to MBCs. In bone metastases, geminin was lower (p<0.001) compared with primary MBCs. In the metastases of the lung, the evaluated markers did not show different expression. According to the median follow-up until the metastatic event, Ki67 was found to be significantly elevated in EMBC (p=0.018).

Conclusions

Ki67 index and geminin distinguish a fraction of MBC with worse prognosis, showing increased levels in the latter in comparison to CBC being tumour-free over a 10-year follow-up period. Ki67 could possibly identify a group of MBCs that develop early DMs.

Geminin overexpression promotes imatinib sensitive breast cancer: a novel treatment approach for aggressive breast cancers, including a subset of triple negative

Breast cancer is the second leading cause of cancer-related deaths in women. Triple negative breast cancer (TNBC) is an aggressive subtype that affects 10–25% mostly African American women. TNBC has the poorest prognosis of all subtypes with rapid progression leading to mortality in younger patients. So far, there is no targeted treatment for TNBC. To that end, here we show that c-Abl is one of several tyrosine kinases that phosphorylate and activate geminin’s ability to promote TNBC. Analysis of >800 breast tumor samples showed that geminin is overexpressed in ∼50% of all tumors. Although c-Abl is overexpressed in ∼90% of all tumors, it is only nuclear in geminin overexpressing tumors. In geminin-negative tumors, c-Abl is only cytoplasmic. Inhibiting c-Abl expression or activity (using imatinib or nilotinib) prevented geminin Y150 phosphorylation, inactivated the protein, and most importantly converted overexpressed geminin from an oncogene to an apoptosis inducer. In pre-clinical orthotopic breast tumor models, geminin-overexpressing cells developed aneuploid and invasive tumors, which were suppressed when c-Abl expression was blocked. Moreover, established geminin overexpressing orthotopic tumors regressed when treated with imatinib or nilotinib. Our studies support imatinib/nilotonib as a novel treatment option for patients with aggressive breast cancer (including a subset of TNBCs)-overexpressing geminin and nuclear c-Abl.

Research status and funding trends of lung cancer biomarkers

Lung cancer is one of malignant tumors with the highest morbidity and mortality in the world. At present, research of early diagnosis, treatment, prognosis, and metastasis associated biomarkers is most active. This article reviewed the research status of lung cancer biomarkers and analyzed the funding situation in the field of lung cancer markers in recent 10 years in China and abroad, to provide a reference for the future basic and clinical translational research of lung cancer biomarkers.

Contrast-enhanced intraoperative ultrasonography for vascular imaging of hepatocellular carcinoma: clinical and biological significance

Abnormal tumor vascularity is one of the typical features of hepatocellular carcinoma (HCC). In this study, the significance of contrast-enhanced intraoperative ultrasonography (CEIOUS) images of HCC vasculature was evaluated by clinicopathological and gene expression analyses. We enrolled 82 patients who underwent curative hepatic resection for HCC with CEIOUS. Clinicopathological and gene expression analyses were performed according to CEIOUS vasculature patterns. CEIOUS images of HCC vasculatures were classified as reticular HCC or thunderbolt HCC. Thunderbolt HCC was significantly correlated with higher alpha-fetoprotein levels, tumor size, histological differentiation, portal vein invasion, and tumor-node-metastasis stage, and these patients demonstrated a significantly poorer prognosis for both recurrence-free survival (P = 0.0193) and overall survival (P = 0.0362) compared with patients who had reticular HCC. Gene expression analysis revealed that a rereplication inhibitor geminin was significantly overexpressed in thunderbolt HCCs (P = 0.00326). In vitro knockdown of geminin gene reduced significantly the proliferation of human HCC cells. Immunohistochemical analysis confirmed overexpression of geminin protein in thunderbolt HCC (P < 0.0001). Multivariate analysis revealed geminin expression to be an independent factor in predicting poor survival in HCC patients (P = 0.0170).

CONCLUSION

CEIOUS vascular patterns were distinctly identifiable by gene expression profiling associated with cellular proliferation of HCC and were significantly related to HCC progression and poor prognosis. These findings might be clinically useful as a determinant factor in the postoperative treatment of HCC.

Expression and prognostic significance of MAP4K4 in lung adenocarcinoma

Accumulating evidence indicates that mitogen-activated protein 4 kinase 4 (MAP4K4) is frequently overexpressed in many types of human cancers, and plays important roles in transformation, invasiveness, adhesion, and cell migration. The aim of the present study was to explore the expression and prognostic significance of MAP4K4 in lung adenocarcinoma. The results of real-time quantitative PCR and Western blotting analysis revealed an enhanced expression of MAP4K4 in lung adenocarcinomas relative to adjacent non-tumorous lung tissues at both transcriptional and translational levels. Immunohistochemistry showed that 130 of 309 (42%) lung adenocarcinomas had high expression of MAP4K4. MAP4K4 overexpression was significantly correlated with histological grade (p=0.027), pT status (p=0.048), pN status (p=0.006), and pleural invasion (p=0.024). Patients with high MAP4K4 expression had a shorter overall survival compared with those with low MAP4K4 expression, regardless of histological grade, pT status, pN status, or pleural invasion status. Multivariate analysis identified MAP4K4 as an independent prognostic factor for lung adenocarcinoma. In conclusion, our results demonstrate that elevated MAP4K4 expression is closely associated with lung adenocarcinoma progression and has an independent prognostic value in predicting overall survival for patients with lung adenocarcinoma.

Spotlight on geminin

In the previous issue of Breast Cancer Research, Gardner and co-workers describe a novel interaction between Geminin, a protein that prevents reinitiation of DNA replication, and Topoisomerase IIα (TopoIIα), an enzyme essential for removing catenated intertwines between sister chromatids. Geminin facilitates the action of TopoIIα, thereby promoting termination of DNA replication at the same time it inhibits initiation. In this manner, Geminin ensures that cells duplicate their genome once, but only once, each time they divide. Remarkably, either depletion of Geminin or over-expression of Geminin inhibits the action of TopoIIα, thereby making Geminin an excellent target for cancer chemotherapy.