Natural History of Malignant Bone Disease in Gastric Cancer: Final Results of a Multicenter Bone Metastasis Survey

Background

Bone metastasis represents an increasing clinical problem in advanced gastric cancer (GC) as disease-related survival improves. In literature, few data on the natural history of bone disease in GC are available.

Patients and Methods

Data on clinicopathology, skeletal outcomes, skeletal-related events (SREs), and bone-directed therapies for 208 deceased GC patients with evidence of bone metastasis were statistically analyzed.

Results

Median time to bone metastasis was 8 months (CI 95%, 6.125–9.875 months) considering all included patients. Median number of SREs/patient was one. Less than half of the patients (31%) experienced at least one and only 4 and 2% experienced at least two and three events, respectively. Median times to first and second SRE were 2 and 4 months, respectively. Median survival was 6 months after bone metastasis diagnosis and 3 months after first SRE. Median survival in patients who did not experience SREs was 5 months. Among patients who received zoledronic acid before the first SRE, the median time to appearance of first SRE was significantly prolonged compared to control (7 months vs 4 months for control; P: 0.0005).

Conclusions

To our knowledge, this retrospective analysis is the largest multicenter study to demonstrate that bone metastases from GC are not so rare, are commonly aggressive and result in relatively early onset of SREs in the majority of patients. Indeed, our large study, which included 90 patients treated with ZOL, showed, for the first time in literature, a significant extension of time to first SRE and increase in the median survival time after diagnosis of bone metastasis. Taken together, these data may support the beneficial effects of ZOL in GC patients.     

Natural History of Malignant Bone Disease in Hepatocellular Carcinoma: Final Results of a Multicenter Bone Metastasis Survey

Background

Bone is an uncommon site of metastasis in patients with advanced hepatocellular carcinoma (HCC). Therefore, there are few studies concerning the natural history of bone metastasis in patients with HCC.

Patients and Methods

Data on clinicopathology, survival, skeletal-related events (SREs), and bone-directed therapies for 211 deceased HCC patients with evidence of bone metastasis were statistically analyzed.

Results

The median age was 70 years; 172 patients were male (81.5%). The median overall survival was 19 months. The median time to the onset of bone metastasis was 13 months (22.2% at HCC diagnosis); 64.9% patients had multiple bone metastases. Spine was the most common site of bone metastasis (59.7%). Most of these lesions were osteolytic (82.4%); 88.5% of them were treated with zoledronic acid. At multivariate analysis, only the Child Score was significantly correlated with a shorter time to diagnosis of bone metastases (p = 0.001, HR = 1.819). The median survival from bone metastasis was 7 months. At multivariate analysis, HCC etiology (p = 0.005), ECOG performance status (p = 0.002) and treatment with bisphosphonate (p = 0.024) were associated with shorter survival after bone disease occurrence. The site of bone metastasis but not the number of bone lesions was associated with the survival from first skeletal related event (SRE) (p = 0.021) and OS (p = 0.001).

Conclusions

This study provides a significant improvement in the understanding the natural history of skeletal disease in HCC patients. An early and appropriate management of these patients is dramatically needed in order to avoid subsequent worsening of their quality of life.     

Positive Lymph Node Metastasis Has a Marked Impact on the Long-Term Survival of Patients with Hepatocellular Carcinoma with Extrahepatic Metastasis

Background

The prognosis of hepatocellular carcinoma (HCC) patients with extrahepatic metastasis is extremely poor. However, what is the main risk factor for survival remains unclear for these patients. We aimed to find out the relative frequency, incidence and locations of extrahepatic metastases and the risk factors of long-term survival of the patients.

Methods

132 HCC patients with extrahepatic metastasis diagnosed by ¹⁸F-FDG PET/CT and conventional workup were enrolled into this study. The incidence and locations of extrahepatic metastases were summarized, and the related risk factors of overall survival were analyzed.

Results

The most frequent extrahepatic metastatic sites were lymph nodes in 72 (54.5%), bone in 33 (25.0%) and lung in 28 (21.2%) patients. On univariate analysis, prothrombin time, Child-Pugh grade, portal/hepatic vein invasion and lymph node metastasis were independent risk factors of overall survival. On multivariate analysis, lymph node metastasis was the only independent risk factor of overall survival. The cumulative survival rates at 1- and 3-years after diagnosis of extrahepatic metastasis of HCC were 34.4% and 9.3%, respectively. The median survival time was 7 months (range 1 ∼38 months). The median survival time for patients with or without lymph node metastasis were 5 months (range 1∼38 months) and 12 months (range 1∼30 months), respectively (P = 0.036).

Conclusions

This study showed lymph nodes to be the most frequent site of extrahepatic metastases for primary HCC. Lymph node metastasis was the main risk factor of overall survival in patients with HCC with extrahepatic metastasis.     

A Genetic Variant in pre-miR-27a Is Associated with a Reduced Renal Cell Cancer Risk in a Chinese Population

Background

MicroRNAs (miRNAs) are a class of small non-coding RNAs to regulate cell differentiation, proliferation, development, and apoptosis. The single nucleotide polymorphism (SNP) rs895819 is located at the terminal loop of pre-miR-27a. Here, we aimed to investigate whether SNP rs895819 was associated with the development of renal cell cancer (RCC) in a Chinese population.

Methods

In this case-control study, we recruited 594 RCC patients and 600 cancer-free controls with frequency matched by age and sex. We genotyped this polymorphism using the TaqMan assay and assessed the effect of this polymorphism on RCC survival. Logistic regression model was used to assess the genetic effects on the development of RCC and interactions between rs895819 polymorphism and risk factors.

Results

Compared with AA homozygote, individuals carrying AG/GG genotypes had a statistically significant reduced susceptibility to RCC (adjusted OR = 0.71, 95% CI = 0.56–0.90). Furthermore, AG/GG genotypes were associated with reduced RCC susceptibility in localized clinical stage (adjusted OR = 0.71, 95% CI = 0.55–0.91), and similar effects were observed in well differentiated and poorly differentiated RCC (adjusted OR = 0.71, 95% CI = 0.55–0.93 for well differentiated, adjusted OR = 0.51, 95% CI = 0.28–0.93 for poorly differentiated). We also observed that rs895819 had multiplicative interactions with age and hypertension. However, the polymorphism did not influence the survival of RCC.

Conclusion

Our results suggest that the pre-miR-27a rs895819 polymorphism can predict RCC risk in a Chinese population. Larger population-based prospective studies should be used to validate our findings.     

Receptor activator of NF-kB (RANK) expression in primary tumors associates with bone metastasis occurrence in breast cancer patients

Background

Receptor activator of NFkB (RANK), its ligand (RANKL) and the decoy receptor of RANKL (osteoprotegerin, OPG) play a pivotal role in bone remodeling by regulating osteoclasts formation and activity. RANKL stimulates migration of RANK-expressing tumor cells in vitro, conversely inhibited by OPG.

Materials and Methods

We examined mRNA expression levels of RANKL/RANK/OPG in a publicly available microarray dataset of 295 primary breast cancer patients. We next analyzed RANK expression by immunohistochemistry in an independent series of 93 primary breast cancer specimens and investigated a possible association with clinicopathological parameters, bone recurrence and survival.

Results

Microarray analysis showed that lower RANK and high OPG mRNA levels correlate with longer overall survival (P = 0.0078 and 0.0335, respectively) and disease-free survival (P = 0.059 and 0.0402, respectively). Immunohistochemical analysis of RANK showed a positive correlation with the development of bone metastases (P = 0.023) and a shorter skeletal disease-free survival (SDFS, P = 0.037). Specifically, univariate analysis of survival showed that “RANK-negative” and “RANK-positive” patients had a SDFS of 105.7 months (95% CI: 73.9–124.4) and 58.9 months (95% CI: 34.7–68.5), respectively. RANK protein expression was also associated with accelerated bone metastasis formation in a multivariate analysis (P = 0.029).

Conclusions

This is the first demonstration of the role of RANK expression in primary tumors as a predictive marker of bone metastasis occurrence and SDFS in a large population of breast cancer patients.     

Human papillomavirus-16 infection in advanced oral cavity cancer patients is related to an increased risk of distant metastases and poor survival

Background

Human papillomavirus (HPV) is an oncogenic virus causing oropharyngeal cancers and resulting in a favorable outcome after the treatment. The role of HPV in oral cavity squamous cell carcinoma (OSCC) remains ambiguous.

Objective

This study aimed to examine the effect of HPV infection on disease control among patients with OSCC following radical surgery with radiation-based adjuvant therapy.

Patients and Method

We prospectively followed 173 patients with advanced OSCC (96% were stage III/IV) who had undergone radical surgery and adjuvant therapy between 2004 and 2006. They were followed between surgery and death or up to 60 months. Surgical specimens were examined using a PCR-based HPV blot test. The primary endpoints were the risk of relapse and the time to relapse; the secondary endpoints were disease-free survival, disease-specific survival, and overall survival.

Results

The prevalence of HPV-positive OSCC was 22%; HPV-16 (9%) and HPV-18 (7%) were the genotypes most commonly encountered. Solitary HPV-16 infection was a poor predictor of 5-year distant metastases (hazard ratio, 3.4; 95% confidence interval, 1.4–8.0; P = 0.005), disease-free survival (P = 0.037), disease-specific survival (P = 0.006), and overall survival (P = 0.010), whereas HPV-18 infection had no impact on 5-year outcomes. The rate of 5-year distant metastases was significantly higher in the HPV-16 or level IV/V metastasis group compared with both the extracapsular spread or tumor depth ≥11-mm group and patients without risk factors (P<0.001).

Conclusions

HPV infections in advanced OSCC patients are not uncommon and clinically relevant. Compared with HPV-16-negative advanced OSCC patients, those with a single HPV-16 infection are at higher risk of distant metastases and poor survival despite undergoing radiation-based adjuvant therapy and require a more aggressive adjuvant treatment and a more thorough follow-up.     

Icotinib Is an Active Treatment of Non-Small-Cell Lung Cancer: A Retrospective Study

Background

Icotinib hydrochloride is a novel epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) with preclinical and clinical activity in non-small cell lung cancer (NSCLC). This retrospective analysis was performed to assess the efficacy of icotinib on patients with non-small-cell lung cancer (NSCLC).

Methods

82 consecutive patients treated with icotinib as first (n = 24) or second/third line (n = 58) treatment at three hospitals in Nanjing were enrolled into our retrospective research. The Response Evaluation Criteria in Solid Tumors (RECIST) was used to evaluate the tumor responses and the progression-free survival (PFS) and overall survival (OS) was evaluated by the Kaplan-Meier method.

Results

Median PFS was 4.0 months (95% CI 2.311–5.689). Median OS was 11.0 months (95% CI 8.537–13.463) in this cohort. Median PFS for first and second/third line were 7.0 months (95% CI 2.151–11.8) and 3.0 months (95% CI 1.042–4.958), respectively. Median OS for first and second/third line were 13.0 months (95% CI 10.305–15.695) and 10.0 months (95% CI 7.295–12.70), respectively. In patients with EGFR mutation (n = 19), icotinib significantly reduced the risk of progression (HR 0.36, 95% CI 0.18–0.70, p = 0.003) and death (HR 0.10, 95% CI 0.02–0.42, p = 0.002) compared with those EGFR status unknown (n = 63). The most common adverse events were acne-like rash (39.0%) and diarrhea (20.7%).

Conclusions

Icotinib is active in the treatment of patients with NSCLC both in first or second/third line, especially in those patients harbouring EGFR mutations, with an acceptable adverse event profile.     

A case-control study of peripheral blood mitochondrial DNA copy number and risk of renal cell carcinoma

Background

Low mitochondrial DNA (mtDNA) copy number is a common feature of renal cell carcinoma (RCC), and may influence tumor development. Results from a recent case-control study suggest that low mtDNA copy number in peripheral blood may be a marker for increased RCC risk. In an attempt to replicate that finding, we measured mtDNA copy number in peripheral blood DNA from a U.S. population-based case-control study of RCC.

Methodology/Principal Findings

Relative mtDNA copy number was measured in triplicate by a quantitative real-time PCR assay using DNA extracted from peripheral whole blood. Cases (n = 603) had significantly lower mtDNA copy number than controls (n = 603; medians 0.85, 0.91 respectively; P = 0.0001). In multiple logistic regression analyses, the lowest quartile of mtDNA copy number was associated with a 60% increase in RCC risk relative to the highest quartile (OR = 1.6, 95% CI = 1.1–2.2; P _trend = 0.009). This association remained in analyses restricted to cases treated by surgery alone (OR _Q1 = 1.4, 95% CI = 1.0–2.1) and to localized tumors (2.0, 1.3–2.8).

Conclusions/Significance

Our findings from this investigation, to our knowledge the largest of its kind, offer important confirmatory evidence that low mtDNA copy number is associated with increased RCC risk. Additional research is needed to assess whether the association is replicable in prospective studies.     

Comprehensive analysis of 5-aminolevulinic acid dehydrogenase (ALAD) variants and renal cell carcinoma risk among individuals exposed to lead

Background

Epidemiologic studies are reporting associations between lead exposure and human cancers. A polymorphism in the 5-aminolevulinic acid dehydratase (ALAD) gene affects lead toxicokinetics and may modify the adverse effects of lead.

Methods

The objective of this study was to evaluate single-nucleotide polymorphisms (SNPs) tagging the ALAD region among renal cancer cases and controls to determine whether genetic variation alters the relationship between lead and renal cancer. Occupational exposure to lead and risk of cancer was examined in a case-control study of renal cell carcinoma (RCC). Comprehensive analysis of variation across the ALAD gene was assessed using a tagging SNP approach among 987 cases and 1298 controls. Occupational lead exposure was estimated using questionnaire-based exposure assessment and expert review. Odds ratios (OR) and 95% confidence intervals (CI) were calculated using logistic regression.

Results

The adjusted risk associated with the ALAD variant rs8177796^CT/TT was increased (OR = 1.35, 95%CI = 1.05–1.73, p-value = 0.02) when compared to the major allele, regardless of lead exposure. Joint effects of lead and ALAD rs2761016 suggest an increased RCC risk for the homozygous wild-type and heterozygous alleles (^GGOR = 2.68, 95%CI = 1.17–6.12, p = 0.01; ^GAOR = 1.79, 95%CI = 1.06–3.04 with an interaction approaching significance (p_int = 0.06).. No significant modification in RCC risk was observed for the functional variant rs1800435^(K68N). Haplotype analysis identified a region associated with risk supporting tagging SNP results.

Conclusion

A common genetic variation in ALAD may alter the risk of RCC overall, and among individuals occupationally exposed to lead. Further work in larger exposed populations is warranted to determine if ALAD modifies RCC risk associated with lead exposure.     

A Functional Variant in the MTOR Promoter Modulates Its Expression and Is Associated with Renal Cell Cancer Risk

Background

The mTOR signaling pathway plays a crucial role in the carcinogenesis of renal cell cancer (RCC). We sought to investigate the influence of genetic variations in the mTOR pathway-related genes on the risk of RCC.

Methods

We genotyped 8 potentially functional polymorphisms in AKT1, AKT2, PTEN and MTOR genes using the TaqMan method in a case-control study of 710 RCC patients and 760 cancer-free subjects. Unconditional logistic regression, adjusted for potential confounding factors, was used to assess the risk associations. We then examined the functionality of the important polymorphisms.

Results

Of the 8 polymorphisms, after adjusting for multiple comparisons, we found a significant association between one variant (rs2295080) in the promoter of MTOR and reduced RCC risk (P = 0.005, OR = 0.74, 95%CI = 0.59–0.91, TG/GG vs. TT). Another variant (rs701848) in the 3′UTR region of PTEN was associated with increased RCC risk (P = 0.014, OR = 1.45, 95%CI = 1.08–1.96, CC vs. TT); however, the association was not significant after adjusting for multiple comparisons. Furthermore, we observed lower MTOR mRNA levels in the presence of the rs2295080G allele in normal renal tissues. The luciferase reporter assay showed that the rs2295080G allele significantly decreased luciferase activity. No other significant association between the selected polymorphisms and RCC risk was observed.

Conclusions

Our results suggest that the functional MTOR promoter rs2295080 variant affects RCC susceptibility by modulating the endogenous MTOR expression level. The risk effects and the functional impact of the MTOR rs2295080 variant need further validation.     

Functional promoter -31G>C variant in survivin gene is associated with risk and progression of renal cell cancer in a Chinese population

Background

Survivin is an inhibitor of apoptosis protein and is involved in the occurrence and progression of human malignancies. Recently, a functional polymorphism (−31G>C, rs9904341) in the promoter of survivin has been shown to influence its expression and confer susceptibility to different types of cancer. The present study was aimed to investigate whether the polymorphism also influences susceptibility and progression of renal cell cancer (RCC) in a Chinese population.

Methods

We genotyped this polymorphism using the TaqMan assay in a case-control study comprised of 710 RCC patients and 760 controls. The logistic regression was used to assess the genetic association with occurrence and progression of RCC.

Results

Compared with the genotypes containing G allele (GG and GC), we found a statistically significant increased occurrence of RCC associated with the CC genotype [P = 0.006, adjusted odds ratio (OR) = 1.38, 95% confidence interval (CI) = 1.08–1.76]. The polymorphism was associated with risk of developing advanced stage (OR = 2.02, 95%CI = 1.34–3.07) and moderately differentiated (OR = 1.75; 95%CI = 1.20–2.54) RCC. Furthermore, the patients carrying the CC genotype had a significantly greater prevalence of high clinical stage disease (P_trend = 0.003). Similar results were also observed when we restricted the analysis to clear cell RCC, a major histological type of RCC.

Conclusions

Our results suggest that the functional −31G>C polymorphism in the promoter of survivin may influence the susceptibility and progression of RCC in the Chinese population. Large population-based prospective studies are required to validate our findings.     

Prognostic Significance of B-Cells and pSTAT3 in Patients with Ovarian Cancer

Background

Several previous studies have identified a strong association between T-cell infiltration and clinical outcome in ovarian cancer. The role of B-cells remains controversial, however.

Methods

Forty-nine paraffin-embedded omental specimens derived from patients with high grade epithelial ovarian cancer were assessed. Immunohistochemical analyses were performed to characterize expression of CD19⁺ B-cells and pSTAT3 as high (>50% positively staining cells [PSCs]) or low (<50% PSCs). The Kaplan-Meier method with log-rank test was used to determine the association between clinicopathologic parameters and overall survival (OS). A multi-variate Cox proportional hazards regression analysis including nature of debulking (primary vs secondary), histology, tumor grade, receipt of prior chemotherapy, B-cell infiltration and pSTAT3 expression was performed.

Results

Median OS was 160.6 months in those patients with low B-cell expression vs 47.3 months in those with high B-cell expression (P = 0.0015). Similarly, median OS was improved in those patients with low pSTAT3 expression (160.6 vs 47.9 months, P = 0.02). In a multivariate model to predict survival, only the degree of B-cell infiltration and clinical stage were retained. pSTAT3 expression did not enter the final model, possibly be due to a high positive correlation with B-cell infiltration (r = 0.82, P<0.0001).

Conclusions

Increased B-cell infiltration and pSTAT3 expression in omental tissue are associated with poorer survival.     

Impact of Age on the Cancer-Specific Survival of Patients with Localized Renal Cell Carcinoma: Martingale Residual and Competing Risks Analysis

Background

Age at diagnosis has been shown to be an independent prognostic factor of localized renal cell carcinoma (RCC) in several studies. We used contemporary statistical methods to reevaluate the effect of age on the cancer-specific survival (CSS) of localized RCC.

Methods and Findings

1,147 patients with localized RCC who underwent radical nephrectomy between 1993 and 2009 were identified in our four institutions. The association between age and CSS was estimated, and the potential threshold was identified by a univariate Cox model and by martingale residual analysis. Competing risks regression was used to identify the independent impact of age on CSS. The median age was 52 years (range, 19–84 years). The median follow-up was 61 months (range, 6–144 months) for survivors. A steep increasing smoothed martingale residual plot indicated an adverse prognostic effect of age on CSS. The age cut-off of 45 years was most predictive of CSS on univariate Cox analysis and martingale residual analysis (p = 0.005). Age ≤45 years was independently associated with a higher CSS rate in the multivariate Cox regression model (HR = 1.59, 95% CI = 1.05–2.40, p = 0.027) as well as in competing risks regression (HR = 3.60, 95% CI = 1.93–6.71, p = 0.001).

Conclusions

Increasing age was associated with a higher incidence of cancer-specific mortality of localized RCC. Age dichotomized at 45 years would maximize the predictive value of age on CSS, and independently predict the CSS of patients with localized RCC.     

Time course and pattern of metastasis of cutaneous melanoma differ between men and women

Background

This study identified sex differences in progression of cutaneous melanoma.

Methodology/Principal Findings

Of 7,338 patients who were diagnosed as an invasive primary CM without clinically detectable metastases from 1976 to 2008 at the University of Tuebingen in Germany, 1,078 developed subsequent metastases during follow up. The metastatic pathways were defined in these patients and analyzed using the Kaplan-Meier method. Multivariate survival analysis was performed using Cox modeling. In 18.7% of men and 29.2% of women (P<0.001) the first metastasis following diagnosis of primary tumor was locoregional as satellite/in-transit metastasis. The majority of men (54.0%) and women (47.6%, P = 0.035) exhibited direct regional lymph node metastasis. Direct distant metastasis from the stage of the primary tumor was observed in 27.3% of men and 23.2% of women (P = 0.13). Site of first metastasis was the most important prognostic factor of survival after recurrence in multivariate analysis (HR:1.3; 95% CI: 1.0–1.6 for metastasis to the regional lymph nodes vs. satellite/in-transit recurrence, and HR:5.5; 95% CI: 4.2–7.1 for distant metastasis vs. satellite/in-transit recurrence, P<0.001). Median time to distant metastasis was 40.5 months (IQR, 58.75) in women and 33 months (IQR, 44.25) in men (P = 0.002). Five-year survival after distant recurrence probability was 5.2% (95% CI: 1.4–2.5) for men compared with 15.3% (95% CI: 11.1–19.5; P = 0.008) for women.

Conclusions/Significance

Both, the pattern of metastatic spread with more locoregional metastasis in women, and the time course with retracted metastasis in women contributed to the more favorable outcome of women. Furthermore, the total rate of metastasis is increased in men. Interestingly, there is also a much more favorable long term survival of women after development of distant metastasis. It remains a matter of debate and of future research, whether hormonal or immunologic factors may be responsible for these sex differences.     

Prognostic Value of Carbonic Anhydrase IX Immunohistochemical Expression in Renal Cell Carcinoma: A Meta-Analysis of the Literature

Background

Carbonic anhydrase IX (CAIX) protein has been correlated with progression and survival in patients with renal cell carcinoma (RCC). The prognostic value of CAIX in RCC however, remains inconclusive according to published works. This study aimed to analyze CAIX as a biological marker to predict RCC patient prognosis.

Methods

A literature search of the PubMed and Web of Knowledge databases was performed to retrieve original studies from their inception to December of 2013. Fifteen studies, collectively including a total of 2611 patients with renal cell carcinoma, were carefully reviewed. Standard meta-analysis methods were applied to evaluate the prognostic impact of CAIX expression on patient prognosis. The hazard ratio (HR) and its 95% confidence interval (CI) were recorded for the relationship between CAIX expression and survival, and the data were analyzed using Review Manager 5.2 software and Stata software 11.0.

Results

In patients with RCC, low CAIX expression was associated with poor disease-specific survival (HR = 1.89, 95% CI: 1.20–2.98, P = 0.006), unfavorable progression-free survival (HR = 2.62, 95% CI: 1.14–6.05, P = 0.02) and worse overall survival (HR = 2.03, 95% CI: 1.28–3.21, P = 0.002). Furthermore, low CAIX expression was significantly associated with the presence of lymph node metastases (odds ratio (OR) = 0.31, 95% CI = 0.15–0.62, P = 0.0009) and distant metastases (OR = 0.66, 95% CI = 0.46–0.96, P = 0.03) and predicted a higher tumor grade (OR = 0.41, 95% CI = 0.31–0.54, P<0.00001).

Conclusions

Low CAIX expression most likely indicates poor prognosis in RCC patients. Moreover, low CAIX expression was significantly associated with unfavorable clinicopathological factors. To strengthen our findings, further well-designed prospective studies should be conducted to investigate the role of CAIX expression in RCC.     

Genetic Variants in RKIP Are Associated with Clear Cell Renal Cell Carcinoma Risk in a Chinese Population

Background

Raf-1 kinase inhibitor protein (RKIP) plays a critical role in tumor development by regulating cell functions such as invasion, apoptosis and differentiation. Down-regulation of RKIP expression has been implicated in the development and progression of renal cell carcinoma (RCC). Herein, we hypothesized that genetic polymorphisms in RKIP might be associated with susceptibility and progression of RCC.

Methods

A total of 5 tagging single-nucleotide polymorphisms (tSNPs) in RKIP were selected and genotyped by SNapShot method in a case-control study of 859 RCC patients and 1004 controls. The logistic regression was used to evaluate the genetic association with occurrence and progression of RCC. The functionality of the important SNP was preliminary examined by qRT-PCR.

Result

We found that the rs17512051 in the promoter region of RKIP was significantly associated with decreased clear cell RCC (ccRCC) risk (TA/AA vs. TT: P = 0.039, OR = 0.78, 95%CI = 0.62–0.99). Another SNP (rs1051470) in the 3′UTR region of RKIP was marginally associated with increased ccRCC risk (TT vs. CC+CT: OR = 1.45, 95%CI = 1.01–2.09). In the stratified analysis, the protective effect of rs17512051 was more predominant in the subgroups of male, non-smokers, non-drinkers as well as subjects without history of diabetes. Furthermore, we observed higher RKIP mRNA levels in the presence of the rs17512051A allele in normal renal tissues.

Conclusion

Our results suggest that the potentially functional RKIP rs17512051 polymorphism may affect ccRCC susceptibility through altering the endogenous RKIP expression level. Risk effects and the functional impact of this polymorphism need further validation.     

Comprehensive evaluation of one-carbon metabolism pathway gene variants and renal cell cancer risk

Introduction

Folate and one-carbon metabolism are linked to cancer risk through their integral role in DNA synthesis and methylation. Variation in one-carbon metabolism genes, particularly MTHFR, has been associated with risk of a number of cancers in epidemiologic studies, but little is known regarding renal cancer.

Methods

Tag single nucleotide polymorphisms (SNPs) selected to produce high genomic coverage of 13 gene regions of one-carbon metabolism (ALDH1L1, BHMT, CBS, FOLR1, MTHFR, MTR, MTRR, SHMT1, SLC19A1, TYMS) and the closely associated glutathione synthesis pathway (CTH, GGH, GSS) were genotyped for 777 renal cell carcinoma (RCC) cases and 1,035 controls in the Central and Eastern European Renal Cancer case-control study. Associations of individual SNPs (n = 163) with RCC risk were calculated using unconditional logistic regression adjusted for age, sex and study center. Minimum p-value permutation (Min-P) tests were used to identify gene regions associated with risk, and haplotypes were evaluated within these genes.

Results

The strongest associations with RCC risk were observed for SLC19A1 (P_min-P = 0.03) and MTHFR (P_min-P = 0.13). A haplotype consisting of four SNPs in SLC19A1 (rs12483553, rs2838950, rs2838951, and rs17004785) was associated with a 37% increased risk (p = 0.02), and exploratory stratified analysis suggested the association was only significant among those in the lowest tertile of vegetable intake.

Conclusions

To our knowledge, this is the first study to comprehensively examine variation in one-carbon metabolism genes in relation to RCC risk. We identified a novel association with SLC19A1, which is important for transport of folate into cells. Replication in other populations is required to confirm these findings.     

Comparative profiling of primary colorectal carcinomas and liver metastases identifies LEF1 as a prognostic biomarker

Purpose

We sought to identify genes of clinical significance to predict survival and the risk for colorectal liver metastasis (CLM), the most common site of metastasis from colorectal cancer (CRC).

Patients and Methods

We profiled gene expression in 31 specimens from primary CRC and 32 unmatched specimens of CLM, and performed Significance Analysis of Microarrays (SAM) to identify genes differentially expressed between these two groups. To characterize the clinical relevance of two highly-ranked differentially-expressed genes, we analyzed the expression of secreted phosphoprotein 1 (SPP1 or osteopontin) and lymphoid enhancer factor-1 (LEF1) by immunohistochemistry using a tissue microarray (TMA) representing an independent set of 154 patients with primary CRC.

Results

Supervised analysis using SAM identified 963 genes with significantly higher expression in CLM compared to primary CRC, with a false discovery rate of <0.5%. TMA analysis showed SPP1 and LEF1 protein overexpression in 60% and 44% of CRC cases, respectively. Subsequent occurrence of CLM was significantly correlated with the overexpression of LEF1 (chi-square p = 0.042), but not SPP1 (p = 0.14). Kaplan Meier analysis revealed significantly worse survival in patients with overexpression of LEF1 (p<0.01), but not SPP1 (p = 0.11). Both univariate and multivariate analyses identified stage (p<0.0001) and LEF1 overexpression (p<0.05) as important prognostic markers, but not tumor grade or SPP1.

Conclusion

Among genes differentially expressed between CLM and primary CRC, we demonstrate overexpression of LEF1 in primary CRC to be a prognostic factor for poor survival and increased risk for liver metastasis.     

Impairment of Bone Health in Pediatric Patients with Hemolytic Anemia

Introduction

Sickle cell anemia and thalassemia result in impaired bone health in both adults and youths. Children with other types of chronic hemolytic anemia may also display impaired bone health.

Study Design

To assess bone health in pediatric patients with chronic hemolytic anemia, a cross-sectional study was conducted involving 45 patients with different forms of hemolytic anemia (i.e., 17 homozygous sickle cell disease and 14 hereditary spherocytosis patients). Biochemical, radiographic and anamnestic parameters of bone health were assessed.

Results

Vitamin D deficiency with 25 OH-vitamin D serum levels below 20 ng/ml was a common finding (80.5%) in this cohort. Bone pain was present in 31% of patients. Analysis of RANKL, osteoprotegerin (OPG) and osteocalcin levels indicated an alteration in bone modeling with significantly elevated RANKL/OPG ratios (control: 0.08+0.07; patients: 0.26+0.2, P = 0.0007). Osteocalcin levels were found to be lower in patients compared with healthy controls (68.5+39.0 ng/ml vs. 118.0+36.6 ng/ml, P = 0.0001). Multiple stepwise regression analysis revealed a significant (P<0.025) influence of LDH (partial r² = 0.29), diagnosis of hemolytic anemia (partial r² = 0.05) and age (partial r² = 0.03) on osteocalcin levels. Patients with homozygous sickle cell anemia were more frequently and more severely affected by impaired bone health than patients with hereditary spherocytosis.

Conclusion

Bone health is impaired in pediatric patients with hemolytic anemia. In addition to endocrine alterations, an imbalance in the RANKL/OPG system and low levels of osteocalcin may contribute to this impairment.     

Study of 320-Slice Dynamic Volume CT Perfusion in Different Pathologic Types of Kidney Tumor: Preliminary Results

Objective

To investigate microcirculatory differences between pathologic types of kidney tumor using 320-slice dynamic volume CT perfusion.

Methods

Perfusion imaging with 320-slice dynamic volume CT was prospectively performed in 85 patients with pathologically proven clear cell renal cell carcinoma (RCC) (n = 66), papillary RCC (n = 7), chromophobe RCC (n = 5), angiomyolipoma (AML) with minimal fat (n = 7), or RCC (n = 78). Equivalent blood volume (Equiv BV), permeability surface-area product (PS; clearance/unit volume = permeability), and blood flow (BF) of tumor and normal renal cortex were measured and analyzed. Effective radiation dose was calculated.

Results

There was a significant difference in all three parameters between tumor and normal renal cortex (P<0.001). Equiv BV was significantly different between RCC and AML with minimal fat (P = 0.038) and between clear cell RCC and AML with minimal fat (P<0.001). Mean Equiv BV and BF were significantly higher in clear cell RCC than in papillary RCC (P<0.001 for both) and mean Equiv BV was higher in clear cell RCC than in chromophobe RCC (P<0.001). The effective radiation dose of the CT perfusion protocol was 18.5 mSv.

Conclusion

Perfusion imaging using 320-slice dynamic volume CT can be used to evaluate hemodynamic features of the whole kidney and kidney tumors, which may be useful in the differential diagnosis of these four pathologic types of kidney tumor.