Cell cycle related proteins as prognostic parameters in radically resected non-small cell lung cancer

CDC25C Protein Expression Correlates with Tumor Differentiation and Clinical Outcomes in Lung Adenocarcinoma

Given that, even after multimodal therapy, early-stage lung cancer (LC) often recurs, novel prognostic markers to help guide therapy are highly desired. The mRNA levels of cell division cycle 25C (CDC25C), a phosphatase that regulates G2/M cell cycle transition in malignant cells, correlate with poor clinical outcomes in lung adenocarcinoma (LUAD). However, whether CDC25C protein detected by immunohistochemistry can serve as a prognostic marker in LUAD is yet unknown. We stained an LC tissue array and a cohort of 61 LUAD tissue sections for CDC25C and searched for correlations between CDC25C staining score and the pathological characteristics of the tumors and the patients' clinical outcomes. Clinical data were retrieved from our prospectively maintained departmental database. We found that high expression of CDC25C was predominant among poorly differentiated LUAD (p < 0.001) and in LUAD > 1cm (p < 0.05). Further, high expression of CDC25C was associated with reduced disease-free survival (p = 0.03, median follow-up of 39 months) and with a trend for reduced overall survival (p = 0.08). Therefore, high expression of CDC25C protein in LUAD is associated with aggressive histological features and with poor outcomes. Larger studies are required to further validate CDC25C as a prognostic marker in LUAD.

The prognostic value of cyclin D1 expression in the survival of cancer patients: A meta-analysis

BACKGROUND

The relationship between the expression of cyclin D1 and cancer prognosis and outcomes in different malignancies has not been fully elucidated.

AIMS

In the presented meta-analysis, we assessed the association between the expression level of cyclin D1 with overall survival (OS) in several cancers.

METHODS

Eligible studies were identified using PubMed, EMBase, Scopus, Web of Sciences and Cochrane Library databases. For the prognostic meta-analysis, study-specific hazard ratios (HRs) of tissue cyclin D1 for survival were obtained. Finally we pooled data derived from one hundred and eight studies comprising 19,224 patients with 10 different cancer types.

RESULTS

In the pooled analysis, high expression of cyclin D1 was significantly related to a poor OS with a pooled HR of 1.11 (95% CI: 1.02-1.20, P = 0.015; random-effects). Sub-group analysis revealed that high expression of cyclin D1 was related to worse OS of head and neck cancers (HR = 2.08, 95% CI: 1.75-2.47; P < 0.001), but not in breast (HR = 1.033, 95% CI: 0.873-1.223, P = 0.702), gastrointestinal (HR = 1.025, 95% CI:0.824-1.275; P = 0.825), bladder (HR = 0.937, CI: 0.844-1.041; P = 0.225) and in lung cancer patients (HR = 1.092, CI: 0.819-1.455; P = 0.549).

CONCLUSION

Further large, prospective, and well-designed trials are warranted to elucidate the precise clinical importance of cyclin D1 overexpression in the prognosis of cancer patients receiving different treatment regimens.

Expression and prognostic relevance of STAT3 and cyclin D1 in non-small cell lung cancer

Aim

To guide clinicians in selecting treatment options for patients with non-small cell lung cancer (NSCLC), it is desirable to have reliable markers predicting clinical outcome. This study analyzed the correlation between signal transducer and activator of transcription 3 (STAT3) and cyclin D1 in NSCLC and their association with clinicopathological features and survival.

Methods

We investigated 65 specimens of NSCLC tissues by immunohistochemistry using STAT3 and cyclin D1 antibodies. First we determined the correlation between STAT3 and cyclin D1 expression and the clinicopathological features of the tumor. Then we assessed the prognostic relevance of STAT3 and cyclin D1.

Results

A significant correlation was found between high levels of STAT3 expression and the degree of tumor differentiation. Additionally, a significant positive correlation was found between the expression of STAT3 and cyclin D1 (r=0.405, p=0.001). The overexpression of STAT3 and the presence of metastasis were significantly associated with shorter overall survival in univariate analysis (p=0.028 and p=0.036, respectively). Multivariate analysis confirmed that STAT3 expression was an independent prognostic factor (p=0.001).

Conclusions

STAT3 might be correlated with tumor differentiation, and its elevated expression may be an adverse prognostic indicator for patients with NSCLC. Activation of the STAT3/cyclin D1 signaling pathway may be attributed to the malignant transformation of NSCLC and may represent a possible target for therapy.

Knocking-down of CREPT prohibits the progression of oral squamous cell carcinoma and suppresses cyclin D1 and c-Myc expression

Background

As a regulator essential for many cell cycle-related proteins, the robust expression of Cell cycle-Related and Expression-elevated Protein in Tumor (CREPT) implicates a poor diagnosis of endoderm and mesoderm-derived tumors. Whether CREPT plays the same role in the tumorigenesis derived from ectodermal tissues remains elusive.

Methods

To explore the role of CREPT in ectoderm-derived tumors, cells from 7oral squamous cell carcinoma (OSCC) lines and 84clinical OSCC samples were exploited in this study. Quantitative PCR, Western blot assay and immunohistochemistry were applied in the evaluation of CREPT, cyclin D1 and c-Myc expression. Knocking-down of CREPT was performed by lentivirus delivering specific shRNA of CREPT. The effects of CREPT on OSCC were examined by cell proliferation, colony formation, apoptosis, cell migration and xenograft implantation experiments.

Results

Compared with human normal oral keratinocytes, OSCC cell lines showed a significantly elevated expression of CREPT in both mRNA and protein levels. Consistently, samples from OSCC patients also exhibited a noticeably stronger CREPT expression than the noncancerous samples. In contrast, knocking down of CREPT in OSCC cell lines significantly reduced proliferation, colony formation and migration as well as the expression of cyclin D1 and c-Myc, but promoted apoptosis. Statistical analysis also suggested that CREPT expression was significantly correlated with the T and N classification of OSCC. Furthermore, CAL27 mouse xenograft model confirmed that down-regulation of CREPT prohibited cyclin D1 and c-Myc expression, through which decreased the in vivo tumor growth, but increased the survival ratio of hosts.

Conclusion

In OSCC cell lines, up-regulated CREPT expression enhanced cell proliferation, migration and cell cycle as well as promoted cyclin D1 and c-Myc expression as it did in endoderm and mesoderm-origin tumors. Our study strongly suggests that CREPT could be used as a marker for the OSCC prognosis and might work as a potential target in future OSCC therapy.

Prognostic markers in lung cancer: is it ready for prime time?

Non-small cell lung cancer (NSCLC) is a heterogeneity disease and to date, specific clinical factors and tumor stage are established as prognostic markers. Nevertheless, prognosis within stage may vary significantly. During the last 3 decades, genes/proteins that drive tumor initiation and progression, such as oncogenes and tumor suppressor genes have been studied as additional potential prognostic markers. The protein markers as evaluated by immunohistochemistry (IHC) have previously dominated these studies. However, with the development of high-throughput techniques to interrogate genome wide genetic or gene expression changes, DNA (copy number and mutation) and RNA (mRNA and microRNA) based markers have more recently been studied as prognostic markers. Largely due to the heterogeneity and complexity of NSCLC, single gene markers including KRAS mutation has not been validated as strong prognostic markers. In contrast, several gene expression signatures representing mRNA levels of multiple genes have been developed and validated in multiple microarray datasets of independent patient cohorts. The salient features of these gene signatures and their potential value to predict benefit from adjuvant chemotherapy is discussed.

CREPT expression correlates with poor prognosis in patients with retroperitoneal leiomyosarcoma

Retroperitoneal leiomyosarcomas (LMSs) are rare gynecological malignancies that display poor prognosis and high mortality. Cell cycle-related and expression-elevated protein in tumor (CREPT) is an oncogene that is involved in the regulation of many cell cycle-related proteins. However, its distribution and clinical significance in retroperitoneal LMS remains poorly understood. This study assessed the histological classifications of postoperative tumor samples from 71 cases of retroperitoneal LMS that were collected at The General Hospital of the People's Liberation Army from January 1998 to December 2012. We found that more than half of the patients displayed positive expressions of CREPT, Ki-67 and PCNA via immunohistochemical analysis. The expression of CREPT correlated with histological grade (P = 0.044), and the PCNA expression level correlated with the differentiation of tumor cells and histological grade (P < 0.001 and P = 0.009, respectively). Multivariate analysis showed that survival was associated with histological grade and the expression level of CREPT (P = 0.011 and P = 0.012, respectively). Kaplan-Meier analysis showed that the patients lacking CREPT expression exhibited significantly longer overall postoperative survival (median, 60.0 months) than the patients displaying CREPT expression (median, 33.0 months), and CREPT expression correlated with distant recurrence within 5 years after surgery (P = 0.004). Western blot analyses showed that CREPT was more strongly expressed in the retroperitoneal LMS tumor tissue than in paired control tissue. Based on the above data, we concluded that CREPT displays unique immunostaining for retroperitoneal LMS tissue and can be used to supplement other currently available retroperitoneal LMS markers.

Relationship of immunohistochemical biomarker expression and lymph node involvement in patients undergoing surgical treatment of NSCLC with long-term follow-up

We try to identify the relationship between immunohistochemical marker expression and lymph node involvement in a cohort of 282 patients followed for 5 years after curative resection for NSCLC. In 189 patients (67%), lymph nodes were unaffected while 93 patients (33%) showed nodal involvement. The expression of 15 molecular markers was determined from each patient by tissue-array immunohistochemistry. Univariate analysis indicated significantly higher expression of E-cadherin, γ-catenin, p27, and p53 in patients with lymph node involvement. In those with unaffected nodes, p16 and Rb were expressed. E-cadherin expression was related to a 50% mortality reduction in patients with node involvement (hazard ratio (HR) 0.5; p = 0.017). c-erbB-2 expression was correlated with a 3.4-fold increase in mortality compared to patients without expression of this marker in subjects without node involvement (HR 3.41; p = 0.017). Multivariate analysis identified c-erbB-2 (HR 2.22; p = 0.089) and p27 (HR 1.44; p = 0.019) as prognostics of mortality while Rb (HR 0.74) indicated a good prognosis. The expression of proteins encoded by oncogenes and tumor suppressor genes was different according to lymph node involvement. The increased mortality related to c-erbB-2 expression in patients with unaffected lymph nodes would suggests a need for adjuvant treatment.

Prognostic value of MET, cyclin D1 and MET gene copy number in non-small cell lung cancer

The aim of this study was to analyze the correlation of the expression of MET and cyclin D1 and MET gene copy number in non-small cell lung cancer (NSCLC) tissues and patient clinicopathologic characteristics and survival. Sixty-one NSCLC tissue specimens were included in the study. The expression of MET and cyclin D1 was evaluated by immunohistochemistry and MET gene copy number was assessed by quantitative real-time polymerase chain reaction (Q-PCR). Positive expression of MET and cyclin D1 protein and increased MET gene copy number occurred in 59.0%, 59.0% and 18.0% of 61 NSCLC tissues, respectively. MET-positivity correlated with poor differentiation (P = 0.009). Increased MET gene copy number was significantly associated with lymph node metastasis (P = 0.004) and advanced tumor stage (P = 0.048), while the expression of cyclin D1 was not associated with any clinicopathologic parameters. There was a significant correlation between the expression of MET and MET gene copy number (P = 0.002). Additionally, the expression of cyclin D1 had a significant association with the expression of MET as well as MET gene copy number (P = 0.002 and P = 0.017, respectively). MET-positivity and increased MET gene copy number were significantly associated with poor overall survival (P = 0.003 and P < 0.001, respectively) in univariate analysis. Multivariate Cox proportional hazard analysis confirmed that the expression of MET and MET gene copy number were prognostic indicators of NSCLC (P = 0.003 and P = 0.001, respectively). The overexpression of MET and the increased MET gene copy number might be adverse prognostic factors for NSCLC patients. The activation of the MET/cyclin D1 signaling pathway may contribute to carcinogenesis and the development of NSCLC, and may represent a target for therapy.

The role of cyclin D1 expression and patient's survival in non-small-cell lung cancer: a systematic review with meta-analysis

BACKGROUND

The role of cell-cycle protein cyclin D1 in lung cancer remains controversial. To clarify its impact on survival in non-small-cell lung cancer (NSCLC), we performed a meta-analysis on the currently available medial literature to quantitatively assess its role on survival of NSCLC according to cyclin D1 status.

METHOD

Published studies that investigated the association between cyclin D1 expression and NSCLC survival were identified. Meta-analysis was performed by using a DerSimonian-Laird model. Funnel plot was used to investigate publication bias and sources of heterogeneity were identified by using meta-regression analysis.

RESULT

A total of 24 studies with 2731 patients were evaluable for this meta-analysis. No statistical significance was found that cyclin D1 expression was associated with poor prognosis in NSCLC (hazard ratio 1.08 [95% CI, 0.80-1.45]) without publication bias found. But there was significant heterogeneity present; meta-regression analysis was used to explore the sources of heterogeneity and revealed that the outcome of analysis was influenced by cutoff values and ethnicity. No difference between positive and negative studies on study quality assessment was present.

CONCLUSION

The cyclin D1 expression is unlikely to be useful as a prognostic marker for NSCLC in clinical practice from current evidence. The conclusion should be confirmed by a large well-designed prospective study.

Tumor suppressors and cell-cycle proteins in lung cancer

The cell cycle is the cascade of events that allows a growing cell to duplicate all its components and split into two daughter cells. Cell cycle progression is mediated by the activation of a highly conserved family of protein kinases, the cyclin-dependent kinases (CDKs). CDKs are also regulated by related proteins called cdk inhibitors grouped into two families: the INK4 inhibitors (p16, p15, p19, and p18) and the Cip/Kip inhibitors (p21, p27, and p53). Several studies report the importance of cell-cycle proteins in the pathogenesis and the prognosis of lung cancer. This paper will review the most recent data from the literature about the regulation of cell cycle. Finally, based essentially on the data generated in our laboratory, the expression, the diagnostic, and prognostic significance of cell-cycle molecules in lung cancer will be examined.

New biomarkers for lung cancer

IMPORTANCE OF THE FIELD

Despite many efforts to improve early detection, lung cancer remains the leading cause of cancer deaths. Stage is the main determinant of prognosis and the basis for deciding treatment options. Screening tests for lung cancer have not been successful so far.

AREAS COVERED IN THE REVIEW

The article reviews the available literature related to biomarkers in use at present and those that could be used for early diagnosis, staging, prognosis, response to therapy and prediction of recurrence. The single biomarkers are analysed, divided according to the technological methods used and the locations of sampling.

WHAT THE READER WILL GAIN

The reader will gain knowledge on biomarkers in use and those now under study. The reader will also gain insights into the difficulties pertaining to the development of biomarkers, results reproducibility and clinical application.

TAKE HOME MESSAGE

Although some markers seem to be promising, at present there is no consensus on the proven value of their clinical use in lung cancer. The future lies probably in a panel of biomarkers instead of individual assays, or in predictive models derived from the integration of clinical variables and gene expression profiles.

Overexpression of c-erbB-2 and loss of p16 have molecular diagnostic relevance but no prognostic value in lung cancer

This study was designed to evaluate the expression of C-erbB-2 and p16 in lung cancers using tissue microarray technology and to determine their clinical and pathological significance. Immunohistochemical C-erbB-2 and p16 expressions and their associations with clinical and pathological features were analyzed in two tissue microarrays. The membranous and cytoplasmic expression rates of C-erbB-2 were 40.5 and 66.5% in non-small cell lung cancers (NSCLCs), and 0 and 9.5% in small cell lung cancers (SCLCs), respectively. The nuclear and cytoplasmic expression rates of p16 were 11.5 and 32.2% in NSCLs, and 45 and 80% in SCLCs, respectively. The cytoplasmic expression of both C-erbB-2 and p16 was more frequent than the membranous expression of C-erbB-2 and the nuclear expression of p16. The rates of overexpression of C-erbB-2 and loss of p16 expression were significantly higher in NSCLCs than in SCLCs (P < 0.05). Neither C-erbB-2 nor p16 expression was significantly associated with age, tumor grade or stage, presence of lymph node metastasis or survival duration. The abnormal expressions of p16 and C-erbB-2 may play a role in the progression of lung cancers. The variations in the expression patterns of C-erbB-2 and p16 between NSCLCs and SCLCs may aid the molecular classification of lung cancer. The abnormal expression of p16 may be involved in the development of NSCLCs, and the overexpression of C-erbB-2 in NSCLCs indicates that it can be a candidate target for gene therapy.

Modulation of lung molecular biomarkers by beta-carotene in the Physicians' Health Study

BACKGROUND

Beta-Carotene supplementation showed neither benefit nor harm among apparently healthy physicians (all men) in the Physicians' Health Study (PHS) trial. The objective of the current investigation was to evaluate how long-term beta-carotene supplementation affects molecular markers of lung carcinogenesis in the PHS.

METHODS

The protein levels of total p53, cyclin D1, proliferating cellular nuclear antigen (PCNA), retinoic acid receptor beta (RARbeta), and cytochrome p450 enzyme 1A1 (CYP1A1) were measured using the immunohistochemical method in 40 available archival lung tissue samples from patients who were diagnosed with lung cancer in the PHS. The protein levels of these markers were compared by category of beta-carotene treatment assignment and other characteristics using unconditional logistic regression models.

RESULTS

The positivity for total p53, RARbeta, cyclin D1, and PCNA was nonsignificantly lower among lung cancer patients who were assigned to receive beta-carotene than those who were assigned to receive beta-carotene placebo. There was a borderline significant difference in CYP1A1 positivity with an OR of 0.2 (95% confidence interval, 0.2-1.1; P = .06) in a comparison of men who received beta-carotene and men who received beta-carotene placebo.

CONCLUSIONS

The 50-mg beta-carotene supplementation on alternate days had no significant influence on molecular markers of lung carcinogenesis that were evaluated in the PHS. This finding provides mechanistic support for the main PHS trial results of beta-carotene, which demonstrated no benefit or harm to the risk of developing lung cancer.

Relationship of phospho-pRb (Ser-807/811) level to exposure to tobacco smoke in primary non-small cell lung cancer

This study was aimed at understanding the effect of smoking on pRb phosphorylation and the clinicopathological significance of phospho-pRb in non-small cell lung cancers (NSCLCs). Phospho-pRb (Ser-807/811) expression was not detected in 149 (39%) of 382 patients, and the mean phospho-pRb (Ser-807/811) level was 5.7%. Squamous cell carcinoma had higher phospho-pRb (Ser-807/811) levels than adenocarcinoma (7.1%+/-10.4% versus 4.7%+/-7.9%; P=0.003). The association between phospho-pRb (Ser-807/811) levels and exposure to tobacco smoke was different according to the statuses of cyclin D1 expression and p16 methylation, suggesting that their statuses might play a role as an effect modifier in the relationship between phospho-pRb (Ser-807/811) levels and exposure to tobacco smoke. In stratified multivariate analysis, phospho-pRb (Ser-807/811) levels were not associated with exposure to tobacco smoke in 38 patients with p16 hypermethylation and cyclin D1 expression >5%, after adjusting for confounding factors. However, in the remaining 344 patients, the mean phospho-pRb (Ser-807/811) levels in patients who had smoked >40 pack years increased by 4.65% (P<0.0001) on average than those who had never smoked. No association was found between the phospho-pRb (Ser-807/811) levels and overall survival. In conclusion, the present study suggests that exposure to tobacco smoke is associated with phosphorylation of pRb in NSCLC patients and its relationship depends on the p16 methylation status and cyclin D1 expression levels.

Identification of genes down-regulated during lung cancer progression: a cDNA array study

Background

Lung cancer remains a major health challenge in the world. Survival for patients with stage I disease ranges between 40–70%. This suggests that a significant proportion of patients with stage I NSCLC may actually be under-staged.

Methods

In order to identify genes relevant for lung cancer development, we carried out cDNA array experiments employing 64 consecutive patients (58 men and 6 women) with a median age of 58 years and stage 1 or stage 2 non-small-cell lung cancer (NSCLC).

Results

Basic cDNA array data identified 14 genes as differentially regulated in the two groups. Quantitative RT-PCR analysis confirmed an effective different transcriptional regulation of 8 out of 14 genes analyzed. The products of these genes belong to different functional protein types, such as extra-cellular matrix proteins and proteases (Decorin and MMP11), genes involved in DNA repair (XRCC1), regulator of angiogenesis (VEGF), cell cycle regulators (Cyclin D1) and tumor-suppressor genes (Semaphorin 3B, WNT-5A and retinoblastoma-related Rb2/p130). Some previously described differences in expression patterns were confirmed by our array data. In addition, we identified and validated for the first time the reduced expression level of some genes during lung cancer progression.

Conclusion

Comparative hybridization by means of cDNA arrays assisted in identifying a series of novel progression-associated changes in gene expression, confirming, at the same time, a number of previously described results.

Cyclin D1 in non-small cell lung cancer: a key driver of malignant transformation

PURPOSE

To review the evidence implicating the deregulation of cyclin D1 in the pathogenesis of non-small cell lung cancer (NSCLC), and to discuss the opportunities for targeted clinical intervention.

METHODS

Data published until June 2006 are summarized, and previously unpublished results from our own research are included.

RESULTS

In normal cells, cyclin D1 complexes with and activates cyclin-dependent kinases (CDK) and acts as a transcriptional regulator. The protein is frequently overexpressed in a wide range of cancers, sometimes coincident with CCND1 (cyclin D1) gene amplification (5-20% of tumours). A low level of somatic mutations have been seen in certain tumours. CCND1 is amplified in NSCLC and cyclin D1 is frequently overexpressed in tumours and pre-invasive bronchial lesions, generally from one parental allele. Mutation analyses revealed a frequent CCND1 gene polymorphism (A870G) that modulates alternative splicing and allows expression of an alternative cyclin D1 transcript (transcript cyclin D1b). The encoded cyclin D1b protein lacks a specific phosphorylation site required for nuclear export. Genotype has been correlated with the risk and/or severity of disease or drug response across a range of malignancies, including lung cancer. Together, these findings suggest a strong pathological role for cyclin D1 deregulation in bronchial neoplasia.

CONCLUSION

Current data indicate that cyclin D1 overexpression is not a consequence of, but rather a pivotal element in the process of malignant transformation in the lung and other tissues. This understanding may open new avenues for lung cancer diagnosis, treatment and prevention.

Immunohistochemical markers of prognosis in non-small cell lung cancer: a review and proposal for a multiphase approach to marker evaluation

Characteristics of the tumour that affect and predict the survival outcome of patients with cancer are prognostic markers for cancer. In non-small cell lung carcinoma (NSCLC), stage is the main determinant of prognosis and the basis for deciding options for treatment. Patients with early-stage tumour are treated by complete surgical resection, which is curative in 40-70% of patients. That there are other factors important in determining the biology of these tumours, especially genes that have a role in metastasis, is indicated. Such factors could potentially be used to further classify patients into groups according to substages that may be treated differently. During the past decade, a large number of proteins that are putatively important in carcinogenesis and cancer biology have been studied for their prognostic value in NSCLC, but none of them have been proved to be sufficiently useful in clinical diagnosis. Several markers (epidermal growth factor receptor, human epidermal growth factor receptor 2, Ki-67, p53 and Bcl-2) have been studied exhaustively. Ki-67, p53 and Bcl-2 are suggested to be important but weak prognostic markers, by meta-analyses of the results. Cyclin E, vascular endothelial growth factor A, p16(INK4A), p27(kip1) and beta-catenin are promising candidates, but require further study in large randomised clinical trial samples by using standardised assays and scoring systems. Some issues and inconsistencies in the reported studies to date are highlighted and discussed. A guideline for a multi-phase approach for conducting future studies on prognostic immunohistochemistry markers is proposed here.

The Future in Diagnosis and Staging of Lung Cancer

Lung cancers at the same stage of disease have markedly different rates of disease progression. In this review, we will address current molecular techniques which provide new opportunities according to diagnosis, prediction of survival or selection of therapy. New molecular techniques might be helpful in TNM staging and lead to additional individual prognostic information. A revised TNM system could include a TNM component and a molecular supplemental component allowing new markers to be evaluated without undermining the value of classic TNM staging. Furthermore, molecular techniques might be helpful in the early or differential diagnosis of lung cancer. Since many new targeted agents are effective only if their respective molecular markers are mutated or expressed at sufficient levels, DNA-based or RNA-based techniques have the potential to influence treatment selection in the future. Overall, we can expect that molecular markers will contribute to a more personalized lung cancer treatment.