BMC Cancer - Latest Articles

Response of the primary tumor in symptomatic and asymptomatic stage IV colorectal cancer to combined interventional endoscopy and palliative chemotherapy

Silke Cameron — 2009-07-01T00:00:00Z

[Background] The treatment of the primary tumor in advanced metastatic colorectal cancer (CRC) is still a matter of discussion. Little attention has thus far been paid to the endoscopically observable changes of the primary in non-curatively resectable stage IV disease.[Methods] 20 patients [14 men, 6 women, median age 67 (39-82) years] were observed after initial diagnosis of non-curatively resectable metastasized symptomatic (83 %) or asymptomatic (17 %) CRC, from June 2002 to April 2009. If necessary, endoscopic tumor debulking was performed. 5-FU based chemotherapy was given immediately thereafter. In 10 patients, chemotherapy was combined with antibody therapy.[Results] Response of the primary was observed in all patients. Local symptoms were treated endoscopically whenever necessary (obstruction or bleeding), and further improved after chemotherapy was started: Four patients showed initial complete endoscopic disappearance of the primary. In an additional 6 patients, only adenomatous tissue was histologically detected. In both these groups, two patients revealed local tumor relapse after interruption of therapy. Local tumor regression or stable disease was achieved in the remaining 10 patients. 15 patients died during the observation time. In 13 cases, death was related to metastatic disease progression. The mean overall survival time was 19.6 (3-71) months. No complications due to the primary were observed.[Conclusions] This study shows that modern anti-cancer drugs combined with endoscopic therapy are an effective and safe treatment of the symptomatic primary and ameliorate local complaints without the need for surgical intervention in advanced UICC stage IV CRC.

Prognostic relevance of Wnt-inhibitory factor-1 (WIF1) and Dickkopf-3 (DKK3) promoter methylation in human breast cancer

Jurgen Veeck — 2009-07-01T00:00:00Z

Background: Secreted Wnt signaling antagonists have recently been described as frequent targets of epigenetic inactivation in human tumor entities. Since gene silencing of certain Wnt antagonists was found to be correlated with adverse patient survival in cancer, we aimed at investigating a potential prognostic impact of the two Wnt antagonizing molecules WIF1 and DKK3 in breast cancer, which are frequently silenced by promoter methylation in this disease. Methods: WIF1 and DKK3 promoter methylation were assessed by methylation-specific PCR with bisulfite-converted DNA from 19 normal breast tissues and 150 primary breast carcinomas. Promoter methylation was interpreted in a qualitative, binary fashion. Statistical evaluations included two-sided Fisher's exact tests, univariate log-rank tests of Kaplan-Meier curves as well as multivariate Cox regression analyses. Results: WIF1 and DKK3 promoter methylation were detected in 63.3% (95/150) and 61.3% (92/150) of breast carcinoma samples, respectively. In normal breast tissues, WIF1 methylation was present in 0% (0/19) and DKK3 methylation in 5.3% (1/19) of samples. In breast carcinomas, WIF1 methylation was significantly associated with methylation of DKK3 (p = 0.009). Methylation of either gene was not associated with clinicopathological parameters, except for DKK3 methylation being associated with patient age (p = 0.007). In univariate analysis, WIF1 methylation was not associated with clinical patient outcome. In contrast, DKK3 methylation was a prognostic factor in patient overall survival (OS) and disease-free survival (DFS). Estimated OS rates after 10 years were 54% for patients with DKK3-methylated tumors, in contrast to patients without DKK3 methylation in the tumor, who had a favorable 97% OS after 10 years (p < 0.001). Likewise, DFS at 10 years for patients harboring DKK3 methylation in the tumor was 58%, compared with 78% for patients with unmethylated DKK3 (p = 0.037). Multivariate analyses revealed that DKK3 methylation was an independent prognostic factor predicting poor OS (hazard ratio (HR): 14.4; 95% confidence interval (CI): 1.9-111.6; p = 0.011), and short DFS (HR: 2.5; 95% CI: 1.0-6.0; p = 0.047) in breast cancer. Conclusions: Although the Wnt antagonist genes WIF1 and DKK3 show a very similar frequency of promoter methylation in human breast cancer, only DKK3 methylation proves as a novel prognostic marker potentially useful in the clinical management of this disease.

Fatty fish and fish omega-3 fatty acid intakes decrease the breast cancer risk: a case-control study

Jeongseon Kim — 2009-06-30T00:00:00Z

Background: Although it is believed that fish omega-3 fatty acids may decrease breast cancer risk, epidemiological evidence has been inconclusive. This study examined the association between fish and fish omega-3 fatty acids intake with the risk of breast cancer in a case-control study of Korean women. Methods: We recruited 358 incident breast cancer patients and 360 controls with no history of malignant neoplasm from the National Cancer Center Hospital between July 2007 and April 2008. The study participants were given a 103-item food intake frequency questionnaire to determine their dietary consumption of fish (fatty and lean fish) and omega-3 fatty acids derived from fish (eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA)). Results: Using a multivariate logistic regression model, high intake of fatty fish was associated with a reduced risk for breast cancer in both pre- and postmenopausal women (OR [95% CI] for highest vs. lowest intake quartiles, p for trend: 0.19 [0.08 to 0.45], p < 0.001 for premenopausal women, 0.27 [0.11 to 0.66], p = 0.005 for postmenopausal women). Similarly, reductions in breast cancer risk were observed among postmenopausal subjects who consumed more than 0.101 g of EPA (OR [95% CI]: 0.38 [0.15 to 0.96]) and 0.213 g of DHA (OR [95% CI]: 0.32 [0.13 to 0.82]) from fish per day compared to the reference group who consumed less than 0.014 g of EPA and 0.037 g of DHA per day. Among premenopausal women, there was a significant reduction in breast cancer risk for the highest intake quartiles of omega-3 fatty acids (ORs [95% CI]: 0.46 [0.22 to 0.96]), compared to the reference group who consumed the lowest quartile of intake. Conclusions: These results suggest that high consumption of fatty fish is associated with a reduced risk for breast cancer, and that the intake of omega-3 fatty acids from fish is inversely associated with postmenopausal breast cancer risk.

The prosurvival role of autophagy in Resveratrol-induced cytotoxicity in human U251 glioma cells

Jun Li — 2009-06-30T00:00:00Z

Background: Previous study reported that resveratrol has anti-tumor activity. In this study, we investigated the involvement of autophagy in the resveratrol-induced apoptotic death of human U251 glioma cells. Methods: The growth inhibition of U251 cells induced by resveratrol was assessed with methyl thiazolyl tetrazolium (MTT). The activation of autophagy and proapoptotic effect were characterized by monodansylcadaverine labeling and Hoechst stain, respectively. Mitochondrialtransmembrane potential (DeltaPsim) was measured as a function of drug treatment using 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazolylcarbocyanine iodide (JC-1). The role of autophagy and apoptosis in the resveratrol-induced death of U251 cells was assessed using autophagic and caspase inhibitors. Immunofluorescence, flow cytometry, and Western blot analysis were used to study the apoptotic and autophagic mechanisms. Results: Methyl thiazolyl tetrazolium (MTT) assays indicated that resveratrol decreased the viability of U251 cells in a dose- and time-dependent manner. Flow cytometry analysis indicated that resveratrol increased cell population at sub-G1 phase, an index of apoptosis. Furthermore, resveratrol-induced cell death was associated with a collapse of the mitochondrial membrane potential. The pan-caspase inhibitor Z-VAD-fmk suppressed resveratrol-induced U251 cell death. Resveratrol stimulated autophagy was evidenced by punctuate monodansylcadaverineMDCstaining and microtubule-associated protein light chain 3 (LC3) immunoreactivty. Resveratrol also increased protein levels of beclin 1 and membrane form LC3 (LC3-II). Autophagy inhibitors 3-methylademine (3-MA) and bafilomycin A1 sensitized the cytotoxicity of resveratrol. Conclusions: Together, these findings indicate that resveratrol induces autophagy in human U251 glioma cells and autophagy suppressed resveratrol-induced apoptosis. This study thus suggests that autophagy inhibitors can increase the cytotoxicity of resveratrol to glioma cells.

Intrinsic bias in breast cancer gene expression data sets

Jonathan Mosley — 2009-06-29T00:00:00Z

Background: While global breast cancer gene expression data sets have considerable commonality in terms of their data content, the populations that they represent and the data collection methods utilized can be quite disparate. We sought to assess the extent and consequence of these systematic differences with respect to identifying clinically significant prognostic groups. Methods: We ascertained how effectively unsupervised clustering employing randomly generated sets of genes could segregate tumors into prognostic groups using four well-characterized breast cancer data sets. Results: Using a common set of 5,000 randomly generated lists (70 genes/list), the percentages of clusters with significant differences in metastasis latencies (HR p-value<0.01) was 62%, 15%, 21% and 0% in the NKI2 (Netherlands Cancer Institute), Wang, TRANSBIG and KJX64/KJ125 data sets, respectively. Among ER positive tumors, the percentages were 38%, 11%, 4% and 0%, respectively. Few random lists were predictive among ER negative tumors in any data set. Clustering was associated with ER status and, after globally adjusting for the effects of ER-alpha gene expression, the percentages were 25%, 33%, 1% and 0%, respectively. The impact of adjusting for ER status depended on the extent of confounding between ER-alpha gene expression and markers of proliferation. Conclusions: It is highly probable to identify a statistically significant association between a given gene list and prognosis in the NKI2 dataset due to its large sample size and the interrelationship between ER-alpha expression and markers of proliferation. In most respects, the TRANSBIG data set generated similar outcomes as the NKI2 data set, although its smaller sample size led to fewer statistically significant results.

CXCR4 expression on circulating pan-cytokeratin positive cells is associated with survival in patients with advanced non-small cell lung cancer

Karen Reckamp — 2009-06-29T00:00:00Z

Background: The CXC chemokine, CXCL12, and its receptor, CXCR4 promote metastases of a variety of solid tumors, including non-small cell lung cancer (NSCLC). The expression of CXCR4 on tumor cells may represent a critical biomarker for their propensity to metastasize. This study was performed to evaluate the hypothesis that co-expression of pan-cytokeratin and CXCR4 may be a prognostic marker for patients with advanced NSCLC. Methods: We evaluated CXCR4 levels on circulating pan-cytokeratin cells from patients with NSCLC. NSCLC tumor and metastases were also assessed for the presence of CXCR4. Results: Pan-cytokeratin positive cells were increased in the circulation of patients with NSCLC, as compared to normal control subjects. Patients with pan-cytokeratin +/CXCR4+ less than or equal to 2,500 cells/ml had a significant improvement in median survival when compared with patients with pan-cytokeratin +/CXCR4+ greater than 2,500 cells/ml (not achieved versus 14 weeks). CXCR4 expression was found on NSCLC tumors and at sites of tumor metastasis. Conclusions: This study suggests that CXCR4 may be a prognostic marker in NSCLC, and provides hypothesis-generating results, which may be important in determining metastatic potential. In future studies, we will prospectively evaluate the prognostic significance of pan-cytokeratin/CXCR4+ cells, and determine the mechanisms involved in the regulation of CXCR4 expression on tumor cells in a larger patient population.

Molecular characterization of EGFR, PDGFRA and VEGFR-2 in cervical adenosquamous carcinoma

Adhemar Longatto-Filho — 2009-06-29T00:00:00Z

Background: Adenosquamous carcinoma of the uterine cervix is an infrequent but aggressive subtype of cervical cancer. A better understanding of its biological behavior is warranted to define more accurate prognosis and therapeutic targets. Currently, the blockage of receptor tyrosine kinase (RTKs) activity is an efficient therapeutic strategy for many different cancers. The objective of this study was to investigate EGFR, PDGFRA and VEGFR2 RTKs overexpression and activating gene mutations in a cohort of 30 adenosquamous carcinomas of the uterine cervix. Methods: EGFR, PDGFRA and VEGFR2 immunohistochemistry was performed in all samples, followed by DNA isolation from the gross macroscopically dissection of the neoplastic area. Screening for EGFR (exons 18-21) and PDGFRA (exons 12, 14 and 18) mutations was done by PCR - single-strand conformational polymorphism (PCR-SSCP). Results: Despite the presence of EGFR immunohistochemical positive reactions in 43% (13/30) of the samples, no EGFR activating mutations in the hotspot region (exons 18-21) were identified. A silent base substitution (CAG>CAA) in EGFR exon 20 at codon 787 (Q787Q) was found in 17 cases (56%). All PDGFRA immunohistochemical reactions were positive and consistently observed in the stromal component, staining fibroblasts and endothelial cells as well as in the cytoplasm of malignant cells. No activating PDGFRA mutations were found, yet, several silent mutations were observed, such as a base substitution in exon 12 (CCA>CCG) at codon 567 (P567P) in 9 cases and in exon 18 (GTC>GTT) at codon 824 (V824V) in 4 cases. We also observed the presence of base substitutions in intron 14 (IVS14+3G>A and IVS14+49G>A) in two different cases, and in intron 18 (IVS18-50insA) in 4 cases. VEGFR-2 positivity was observed in 22 of 30 cases (73.3%), and was significantly associated with lack of metastasis (p=0.038). Conclusion: This is the most extensive analysis of EGFR, PDGFRA and VEGFR-2 in cervical adenosquamous carcinomas. Despite the absence of EGFR and PDGFRA activating mutations, the presence of overexpression of these three important therapeutic targets in a subset of cases may be important in predicting the sensitivity of adenosquamous carcinoma to specific anti-RTKs drugs.

A simple method for co-segregation analysis to evaluate the pathogenicity of unclassified variants; BRCA1 and BRCA2 as an example

Leila Mohammadi — 2009-06-29T00:00:00Z

Background: Assessment of the clinical significance of unclassified variants (UVs) identified in BRCA1 and BRCA2 is very important for genetic counselling. The analysis of co-segregation of the variant with the disease in families is a powerful tool for the classification of these variants. Statistical methods have been described in literature but these methods are not always easy to apply in a diagnostic setting. Methods: We have developed an easy to use method which calculates the likelihood ratio (LR) of an UV being deleterious, with penetrance as a function of age of onset, thereby avoiding the use of liability classes. The application of this algorithm is publicly available (http://www.msbi.nl/cosegregation). It can easily be used in a diagnostic setting since it requires only information on gender, genotype, present age and/or age of onset for breast and/or ovarian cancer. Results: We have used the algorithm to calculate the likelihood ratio in favour of causality for 3 UVs in BRCA1 (p.M18T, p.S1655F and p.R1699Q) and 5 in BRCA2 (p.E462G p.Y2660D, p.R2784Q, p.R3052W and p.R3052Q). Likelihood ratios varied from 0.097 (BRCA2, p.E462G) to 230.69 (BRCA2, p.Y2660D). Typing distantly related individuals with extreme phenotypes (i.e. very early onset cancer or old healthy individuals) are most informative and give the strongest likelihood ratios for or against causality. Conclusions: Although co-segregation analysis on itself is in most cases insufficient to prove pathogenicity of an UV, this method simplifies the use of co-segregation as one of the key features in a multifactorial approach considerably.

A phase III clinical trial of exercise modalities on treatment side-effects in men receiving therapy for prostate cancer

Robert Newton — 2009-06-29T00:00:00Z

Background: Androgen deprivation therapy (ADT) is accompanied by a number of adverse side effects including reduced bone mass and increased risk for fracture, reduced lean mass and muscle strength, mood disturbance and increased fat mass compromising physical functioning, independence, and quality of life. The purpose of this investigation is to examine the effects of long term exercise on reversing musculoskeletal-related side effects, and cardiovascular and diabetes risk factors in men receiving androgen deprivation for their prostate cancer. Specifically, we aim to investigate the effects of a 12-month exercise program designed to load the musculoskeletal system and reduce cardiovascular and diabetes disease progression on the following primary endpoints: 1) bone mineral density; 2) cardiorespiratory function and maximal oxygen capacity; 3) body composition (lean mass and fat mass); 4) blood pressure and cardiovascular function; 5) lipids and glycemic control; and 6) quality of life and psychological distress. Methods: Multi-site randomized controlled trial of 195 men (65 subjects per arm) undergoing treatment for prostate cancer involving ADT in the cities of Perth and Brisbane in Australia. Participants will be randomized to (1) resistance/impact loading exercise, (2) resistance/cardiovascular exercise groups and (3) usual care/delayed exercise. Participants will then undergo progressive training for 12 months. Measurements for primary and secondary endpoints will take place at baseline, 6 and 12 months (end of the intervention).DiscussionThe principal outcome of this project will be the determination of the strength of effect of exercise on the well established musculoskeletal, cardiovascular and insulin metabolism side effects of androgen deprivation in prostate cancer patients. As this project is much longer term than previous investigations in the area of exercise and cancer, we will gain knowledge as to the continuing effects of exercise in this patient population specifically targeting bone density, cardiovascular function, lean and fat mass, physical function and falls risk as primary study endpoints. In terms of advancement of prostate cancer care, we expect dissemination of the knowledge gained from this project to reduce fracture risk, improve physical and functional ability, quality of life and ultimately survival rate in this population.

The epidemiology and survival of extrapulmonary small cell carcinoma in South East England, 1970-2004

Yien Ning Wong — 2009-06-29T00:00:00Z

Background: Extrapulmonary small cell carcinoma (EPSCC) is a rare cancer and few studies describe its epidemiology. Our objectives were to compare the incidence and survival of EPSCC in South East England with small cell carcinoma of the lung (SCLC), to determine the most common anatomical presenting sites for EPSCC and to compare survival in EPSCC by disease stage and site of diagnosis. Methods: We used data from the Thames Cancer Registry database for South East England between 1970 and 2004 to determine the incidence, most common anatomical sites, and survival by site, and stage of EPSCC. 1618 patients registered with EPSCC were identified. We calculated the age-standardised incidence rate for EPSCC using the European standard population and compared this to that for SCLC. We calculated survival using the Kaplan-Meier method for EPSCC and SCLC, and reported 3-year survival for different EPSCC anatomical sites and disease stages. Results: The incidence of EPSCC was much lower than for SCLC, similar in males and females, and stable throughout the study period, with incidence rates of 0.45 per 100,000 in males and 0.37 in females during 2000-2004. In general, patients with EPSCC had a better 3-year survival (19%) than SCLC (5%). The most common anatomical sites for EPSCC were oesophagus (18%), other gastrointestinal (15%), genitourinary (20%), head and neck (11%), and breast (10%). Breast EPSCC had the best 3-year survival (60%) and gastrointestinal EPSCC the worst (7%). Conclusion: This study suggests that EPSCC has a stable incidence and confirms that it presents widely, but most commonly in the oesophagus and breast. Site and extent of disease influence survival, with breast EPSCC having the best prognosis. Further studies using standardised diagnosis, prospective case registers for uncommon diseases and European cancer registries are needed to understand this disease.