Genetic variations in regulator of G‐protein signaling (RGS) confer risk of bladder cancer

BACKGROUND:

Alterations in the regulator of G‐protein signaling (RGS) pathway have been implicated in several cancers; therefore, the authors investigated the role of such alterations in overall bladder cancer risk, recurrence, progression, and survival.

METHODS:

In this case‐control series, 803 patients with bladder cancer were frequency‐matched with a control cohort of 803 healthy individuals. Ninety‐five single‐nucleotide polymorphisms (SNPs) in 17 RGS genes were investigated for an association with overall bladder cancer risk, recurrence, and progression in patients who had nonmuscle‐invasive bladder cancer (NMIBC) and for an association with death in patients who had muscle‐invasive bladder cancer (MIBC). Cumulative effects and classification and regression tree analyses were performed for SNPs that were associated with overall bladder cancer risk. Kaplan‐Meier plots were created to evaluate differences in the survival of patients with MIBC.

RESULTS:

Reference SNP 10759 (rs10759) on the RGS4 gene demonstrated the greatest association with overall bladder cancer risk, conferring a 0.77‐fold reduced risk with an increasing number of variant alleles (P < .001). A cumulative effects analysis that included all 5 significant SNPs demonstrated an increasing risk with the number of unfavorable genotypes (odds ratio, 4.13; 95% confidence interval, 2.14‐7.98). In patients with NMIBC, 11 SNPs were identified that had an association with disease recurrence, and 13 SNPs were associated with disease progression. Of the 10 SNPs that were associated with death in patients with MIBC, rs2344673 in an additive model was the most significant and was associated with a decreased median survival of 13.3 months compared with 81.9 months in individuals without a variant allele.

CONCLUSIONS:

Genetic variations in the RGS pathway were associated with the overall risk of bladder cancer, recurrence, and progression in patients with NMIBC and with the risk of death in patients with MIBC. Cancer 2013. © 2013 American Cancer Society.     

Potentially functional polymorphisms in DNA repair genes and non-small-cell lung cancer survival: a pathway-based analysis

To assess systematically whether potentially functional polymorphisms in DNA repair genes influence the clinical behavior of non‐small‐cell lung cancer (NSCLC), we examined the impact of a comprehensive panel of 218 signal nucleotide polymorphisms (SNP) in 50 candidate DNA repair genes on overall survival of NSCLC in a case‐cohort of 568 lung cancer patients. SNPs associated with lung cancer prognosis primarily mapped to 14 genes in different repair pathways, and 6 SNPs were remained in the final model after multivariate stepwise Cox regression analysis: ATM rs189037; MRE11A rs11020802; ERCC2 rs1799793; MBD4 rs140693; XRCC1 rs25487, and PMS1 rs5742933. In the combined analysis of these 6 SNPs, an increasing number of unfavorable loci was associated with a poorer prognosis (P for trend: <0.0001) and patients having 2–4 unfavorable loci had a 1.99‐fold elevated risk of death 95% confidence interval (CI) = 1.58–2.50, compared with those carrying 0–1 unfavorable loci, and this elevated risk was more evident among stages I–II patients (hazard ratio = 3.04, 95% CI = 1.86–4.98, P for heterogeneity: 0.07). Furthermore, a significant effect of SNPs in nucleotide excision repair pathway on lung cancer survival was observed among 185 stages III–IV patients treated with platinum‐based chemotherapy without surgical operation: XPC rs2228000 (Ala499Val; P = 0.002) and ERCC1 rs11615 (Asn118Asn; P = 0.012). Our data indicate that potentially functional polymorphisms in DNA repair genes may serve as candidate prognostic markers of clinical outcome of NSCLC. © 2011 Wiley Periodicals, Inc.     

Gemcitabine metabolic and transporter gene polymorphisms are associated with drug toxicity and efficacy in patients with locally advanced pancreatic cancer

BACKGROUND:

It has not been well established whether genetic variations can be biomarkers for clinical outcome of gemcitabine therapy. The purpose of this study was to identify single nucleotide polymorphisms (SNPs) of gemcitabine metabolic and transporter genes that are associated with toxicity and efficacy of gemcitabine‐based therapy in patients with locally advanced pancreatic cancer.

METHODS:

The authors evaluated 17 SNPs of the CDA,dCK, DCTD, RRM1, hCNT1‐3, and hENT1 genes in 149 patients with locally advanced pancreatic cancer who underwent gemcitabine‐based chemoradiotherapy. The association of genotypes with neutropenia, tumor response to therapy, overall survival, and progression‐free survival (PFS) was analyzed by logistic regression, log‐rank test, Kaplan‐Meier plot, and Cox proportional hazards regression.

RESULTS:

The CDA A‐76C, dCK C‐1205T, RRM1 A33G, and hENT1 C913T genotypes were significantly associated with grade 3 to 4 neutropenia (P = .020, .015, .003, and .017, respectively).The CDA A‐76C and hENT1 A‐201G genotypes were significantly associated with tumor response to therapy (P = .017 and P = .019). A combined genotype effect of CDA A‐76C, RRM1 A33G, RRM1 C‐27A, and hENT1 A‐201G on PFS was observed. Patients carrying 0 to 1 (n = 64), 2 (n = 50), or 3 to 4 (n = 17) at‐risk genotypes had median PFS times of 8.3, 6.0, and 4.2 months, respectively (P = .002).

CONCLUSIONS:

The results indicated that some polymorphic variations of drug metabolic and transporter genes may be potential biomarkers for clinical outcome of gemcitabine‐based therapy in patients with locally advanced pancreatic cancer. Cancer 2010. © 2010 American Cancer Society.     

Association of multi-drug resistance gene polymorphisms with pancreatic cancer outcome

BACKGROUND:

The purpose of this study was to identify single nucleotide polymorphisms (SNPs) of multidrug resistance genes that are associated with clinical outcome in patients with potentially resectable pancreatic adenocarcinoma who were treated with preoperative gemcitabine‐based chemoradiotherapy at M. D. Anderson Cancer Center.

METHODS:

We selected 8 SNPs of 7 drug resistance genes, including MDR1 (ABCB1), MRP1‐5 (ABCC1‐5), and BCRP (ABCG2), reported to be important in mediating drug resistance. Genotype was determined by the Taqman method. The associations of genotype with tumor response to therapy and overall survival (OS) were evaluated using log‐rank test, Cox regression, and logistic regression models.

RESULTS:

MRP5 A‐2G AA genotype showed significant association with OS (log‐rank P = .010). The hazard ratio (95% confidence interval) was 1.65 (1.11‐2.45) after adjusting for clinical predictors. The MRP2 G40A GG genotype had a weak association with reduced OS (log‐rank P = .097). A combined effect of the two genotypes on OS was observed. Patients with none of the adverse genotypes had a median survival time (MST) of 34.0 months, and those with 1‐2 deleterious alleles had a significantly lower MST of 20.7 months (log‐rank P = .006). MRP2 G40A GG genotype was also significantly associated with poor histological response to chemoradiotherapy (P = .028).

CONCLUSIONS:

These observations suggest a potential role of polymorphic variants of drug resistance genes in predicting therapeutic efficacy and survival of patients with potentially resectable pancreatic cancer. Cancer 2011. © 2010 American Cancer Society.     

Xeroderma pigmentosum complementation group C single-nucleotide polymorphisms in the nucleotide excision repair pathway correlate with prolonged progression-free survival in advanced ovarian cancer

BACKGROUND:

The nucleotide excision repair (NER) pathway is the principal DNA repair pathway for removing bulky platinum DNA adducts. Suboptimal DNA repair may lead to improved response to platinum agents. The objective of this study was to determine whether single‐nucleotide polymorphisms (SNPs) in NER pathway genes could be markers of platinum response in ovarian cancer.

METHODS:

The authors identified patients with advanced‐stage, papillary serous ovarian cancer who underwent primary cytoreductive surgery followed by platinum‐based chemotherapy. DNA was isolated from peripheral blood specimens. Twenty‐two SNPs within NER genes (xeroderma pigmentosum [XP] complementation group A [XPA], XPB/excision repair cross‐complementing rodent repair deficiency, complementation group 3 [ERCC3], XPC, XPD/ERCC2, XPF/ERCC4, XPG/ERCC5, Cockayne syndrome group B protein [CSB]/ERCC8, ERCC1) were genotyped using polymerase chain reaction analysis.

RESULTS:

In total, 139 patients with stage III and IV papillary serous ovarian cancer were genotyped. The XPC (reference SNP 3731108 [rs3731108]) adenosine‐guanine (AG)/AA genotype versus the GG genotype was associated with prolonged a progression‐free survival (PFS) of 21.3 months versus 13.4 months (hazard ratio [HR], 0.63; 95% confidence interval [CI], 0.42‐0.95; P = .03). The XPC (rs1124303) guanosine‐thymidine (GT)/GG genotype versus the TT genotype was associated with a prolonged PFS of 22.8 months versus 14.9 months (HR, 0.47; 95% CI, 0.24‐0.94; P = .03). The XPC poly(AT) (PAT) (?/+)/(?/?) genotype versus the (+/+) genotype was associated with a prolonged PFS of 17 months versus 11.6 months (HR, 0.56; 95% CI, 0.36‐0.89; P = .01). The XPF/ERCC4 (rs12926685) cytidine‐thymidine (CT)/CC genotype versus the TT genotype was associated with a prolonged PFS of 16.7 months versus 12.4 months (HR, 0.63; 95% CI, 0.41‐0.95; P = .03). On multivariate analysis adjusting for breast cancer (BRCA) gene and cytoreductive surgery status, the XPC SNPs remained significantly associated with prolonged PFS.

CONCLUSIONS:

The current results indicated that XPC is a key component of the NER pathway that participates in DNA damage repair. SNPs in the XPC gene may represent novel markers of ovarian cancer response to platinum‐based chemotherapy. Cancer 2012;. © 2011 American Cancer Society.     

Examining stage IIB survival in a population‐based cohort of patients with colorectal cancer

BACKGROUND:

In Nova Scotia, Canada, a previous study of colorectal cancer (CRC) cases diagnosed between January 1, 2001, and December 31, 2005, found that patients with stage IIB CRC had similar 5‐year overall survival (OS) to those with stage IIIC cancer. This study sought to examine factors contributing to the observed stage IIB outcome, specifically nodal harvest, receipt of chemotherapy, and use of a new coding system to derive stage.

METHODS:

The provincial cancer registry identified all CRC cases diagnosed during the study period and staged this cohort using the Collaborative Stage (CS) Data Collection System. All patients with stage II and III cancer in the cohort were examined. Kaplan‐Meier (KM) survival curves compared 5‐year OS for patients with stage IIB cancer based on the factors of interest, and compared patients with stage IIB cancer to those with stage IIA and III cancer.

RESULTS:

OS for patients with stage IIB cancer (n = 187) was 44.7%, and differed depending on adequacy of nodal harvest (P = .005) and whether pathological or clinical/mixed evidence was used to derive stage (P = .013). Pathologically‐staged patients with stage IIB cancer who had adequate nodal harvest had marginally improved OS compared to pathologically‐staged patients who had inadequate nodal harvest (P = .07), and improved survival compared to patients with clinical/mixed stage (P = .004). Pathologically‐staged patients with stage IIB cancer with adequate nodal harvest demonstrated similar 5‐year OS to those with stage IIA and III cancer (P = .52 and P = .25, respectively). Cox proportional hazards models supported these findings.

CONCLUSIONS:

The inclusion of clinical/mixed evidence into staging classification and, perhaps to a lesser extent, the adequacy of nodal harvest appear to contribute to the observed worse survival for patients with stage IIB versus stage III cancer. Cancer 2012. © 2012 American Cancer Society.     

Association of VEGF and VEGFR2 single nucleotide polymorphisms with hypertension and clinical outcome in metastatic clear cell renal cell carcinoma patients treated with sunitinib

PURPOSE:

Biomarkers that predict response or toxicity to antiangiogenic therapy are sought to favorably inform the risk/benefit ratio. This study evaluated the association of vascular endothelial growth factor (VEGF) and VEGF receptor 2 (VEGFR2) genetic polymorphisms with the development of hypertension (HTN) and clinical outcome in metastatic clear cell renal cell carcinoma (MCCRCC) patients treated with sunitinib.

PATIENT AND METHODS:

Sixty‐three MCCRCC patients receiving sunitinib (50 mg 4/2) with available blood pressure (BP) data and germline DNA were retrospectively identified. A panel of candidate VEGF and VEGFR2 single nucleotide polymorphisms (SNPs) were evaluated for associations with the development of hypertension and clinical outcome.

RESULTS:

VEGF SNP ?634 genotype was associated with the prevalence and duration of sunitinib‐induced hypertension (as defined by systolic pressure ≥150 mmHg and/or diastolic pressure ≥90 mmHg) in both univariable analysis (P = .03 and .01, respectively) and multivariable analysis, which adjusted for baseline BP and use of antihypertension medication (P = .05 and .02, respectively). Patients with the GG genotype were estimated to have a greater likelihood of being hypertensive during treatment compared with patients with the CC genotype (odds ratio of 13.62, 95% confidence interval [CI] 3.71‐50.04). No single VEGF or VEGFR SNPs were found to correlate with clinical outcome. However, the combination of VEGF SNP 936 and VEGFR2 SNP 889 were associated with overall survival after adjustment for prognostic risk group (P = .03).

CONCLUSIONS:

In MCCRCC patients treated with sunitinib, VEGF SNP ?634 is associated with hypertension and a combination of VEGF SNP 936 and VEGFR2 SNP 889 genotypes is associated with overall survival. Cancer 2012;. © 2011 American Cancer Society.     

Identification of candidate genes carrying polymorphisms associated with the risk of colorectal cancer by analyzing the colorectal mutome and microRNAome

BACKGROUND:

The presence of single‐nucleotide polymorphisms (SNPs) within the 3′‐untranslated regions of genes could affect the binding between a microRNA (miRNA) and its target, with consequences on gene expression regulation. Considering the important role of miRNAs in carcinogenesis, it is hypothesized here that these SNPs could also affect the individual risk of colorectal cancer (CRC).

METHODS:

To test this hypothesis, a list was developed of 140 somatically mutated genes deduced from previous works on the mutome of the CRC. A further selection was conducted of SNPs within target sites for miRNAs that are expressed only in the colorectum (the colorectal microRNAome) and having adequate population frequencies. This yielded 12 SNPs that were genotyped in a case‐control association study on 717 colorectal cases and 1171 controls from the Czech Republic.

RESULTS:

Statistically significant associations were found between the risk of CRC and the variant alleles of KIAA0182 (rs709805) (odds ratio = 1.57; 95% confidence interval = 1.06‐2.78, for the variant homozygotes) and NUP210 genes (rs354476) (odds ratio = 1.36; 95% confidence interval = 1.02‐1.82, for the variant homozygotes).

CONCLUSIONS:

The results support the study hypothesis and highlight the importance of SNPs within miRNA‐dependent regulatory regions. Further studies on the role exerted by NUP210 and KIAA0182 in colorectal carcinogenesis are warranted. Cancer 2012. © 2012 American Cancer Society.     

The role of salvage surgery in patients with recurrent squamous cell carcinoma of the oropharynx

BACKGROUND:

The objective of this study was to comprehensively review overall survival, functional outcomes, and prognostic factors in patients who underwent salvage surgery for locally recurrent squamous cell carcinoma of the oropharynx (SCCOP) after initial radiotherapy.

METHODS:

The authors retrospectively reviewed 1681 consecutive patients who completed definitive therapy for primary SCCOP and identified 168 patients with locally recurrent SCCOP who underwent salvage surgery (41 patients), reirradiation or brachytherapy (18 patients), palliative chemotherapy (70 patients), or supportive care (39 patients).

RESULTS:

Twenty‐six of 39 patients (67%) developed a second recurrence after salvage surgery. The 3‐year overall survival rate for patients who underwent salvage surgery or received reirradiation, palliative chemotherapy, or supportive care were 48.7%, 31.6%, 3.7%, and 5.1%, respectively. For patients who underwent salvage surgery, older age (P = .03), the absence of a disease‐free interval (P < .01), and advanced recurrent tumor stage (P = .07) were associated with lower overall survival. Patients with recurrent neck disease (P = .01) and positive surgical margins (P = .04) had higher rates of recurrence after salvage surgery. Postoperative complications occurred in 19 patients (46%), and there were no perioperative deaths. Functionally, 71% of patients demonstrated ≥80% speech intelligibility, 68% were able to tolerate some oral intake, and 87% who required a tracheotomy subsequently were decannulated.

CONCLUSIONS:

Age, disease‐free interval, recurrent tumor stage, recurrent neck disease, and surgical margin status influenced overall survival or recurrence rate after salvage surgery for recurrent SCCOP. Although most patients had good functional outcomes, only a select group of patients with recurrent SCCOP achieved long‐term survival after salvage surgery. Cancer 2009. © 2009 American Cancer Society.     

The prognostic value of c‐Kit,K‐ras codon 12, and p53 codon 72 mutations in Egyptian patients with stage II colorectal cancer

BACKGROUND:

The prognosis for patients with colorectal cancer (CRC) depends mainly on standard clinicopathologic factors. However, patients with similar disease characteristics exhibit various outcomes, especially in stage II. Therefore, the identification of molecular prognostic markers is needed to predict patient outcomes.

METHODS:

The authors assessed the prognostic value of c‐Kit (also called cluster of differentiation 117 [CD117] or KIT), cyclooxygenase‐2 (COX‐2), tumor protein 53 (p53), and Kirsten rat sarcoma viral oncogene homolog (K‐ras) aberrations in 90 patients with stage II CRC using immunohistochemistry and molecular techniques. The results were correlated with standard clinicopathologic prognostic factors, overall survival (OS), and disease‐free survival (DFS).

RESULTS:

COX2 and c‐Kit overexpression was detected in 54.6% and 59.3% of patients, respectively. Overexpression of p53 was detected in 47 patients, including 29 who had mutations, and a unique mutation pattern was detected with 3 hotspots at codons 72, 245, and 273. Overexpression of ras was detected in 44 patients, including 37 who had mutations. On multivariate analysis, c‐Kit overexpression, p53 codon 72 mutations, perforation, and performance status were independent prognostic factors for DFS (P = .054, P = .015, P < .0001, and P = .043, respectively); whereas codon 12 K‐ras mutation, performance status, and perforation were independent prognostic factors for OS (P = .033, P = .006, and P < .0001, respectively).

CONCLUSIONS:

The current results provide evidence for the prognostic value of c‐Kit overexpression in patients with stage II CRC. The high p53 mutation rate and the unique hotspot in codon 72 have not been reported previously in CRC. This may be related to environmental or racial features that are unique to the studied population. Cancer 2010. © 2010 American Cancer Society.     

Intra‐arterial iodine‐131‐lipiodol for unresectable hepatocellular carcinoma

BACKGROUND:

Hepatic artery administration of iodine‐131‐Lipiodol serves as a modality that delivers targeted radiation therapy to hepatocellular carcinoma. Its efficacy has been promising according to trials conducted in the adjuvant setting after hepatic resection. Further investigation of its role in the palliative setting is warranted.

METHODS:

A retrospective review of 72 patients with unresectable hepatocellular carcinoma treated with iodine‐131‐Lipiodol and followed up by the St. George Hospital Sydney's hepatobiliary service was conducted. Efficacy of treatment was determined based on progression‐free and overall survival as the endpoints using the Kaplan‐Meier method.

RESULTS:

Sixty men and 12 women with a mean age of 65 years (standard deviation = 11) underwent iodine‐131‐Lipiodol treatment. Chronic viral hepatitis was present in 29 (41%) patients. Fifty (69%) patients were Child‐Pugh class A. Median progression‐free survival was 6 months, and overall survival was 14 months; the 1‐, 2‐, and 3‐year survival rates were 52%, 33% and 20%, respectively. Factors associated with survival include the American Joint Committee on Cancer stage (P = .03), Barcelona Clinic Liver Cancer stage (P = .05), Cancer of the Liver Italian Program score (P = .008), tumor size (P = .01), extrahepatic disease (P < .001), previous surgery (P = .02), and response to treatment (P < .001). The response to treatment was identified through a multivariate analysis as the single independent predictor for survival (hazard ratio, 3.5; 95% confidence interval, 2.2‐5.4; P < .001).

CONCLUSIONS:

Encouraging survival outcomes may be derived through administration of iodine‐131‐Lipiodol in patients with unresectable hepatocellular carcinoma. The overall success of treatment may be determined by the response to treatment. Cancer 2010. © 2010 American Cancer Society.     

Cytoreductive surgery plus hyperthermic intraperitoneal chemotherapy improves survival of patients with peritoneal carcinomatosis from colorectal cancer: A case‐control study from a Chinese center

Background

Advanced colorectal cancer (CRC) is prone to developing peritoneal carcinomatosis (PC). This case‐control study was to compare the efficacy and safety of cytoreductive surgery (CRS) versus CRS plus hyperthermic intraperitoneal chemotherapy (HIPEC) in Chinese patients with CRC PC.

Methods

The 62 consecutive PC patients were treated with CRS (Control group, n = 29) or CRS + HIPEC (Study group, n = 33). The primary end point was overall survival (OS), the secondary end points were perioperative safety profiles.

Results

For the comparison of Control versus Study groups, the peritoneal cancer index (PCI) ≤20 was 13 (44.8%) versus 16 (48.5%) patients (P = 0.78), complete cytoreduction (CC0‐1) was achieved in 9 (31.0%) versus 14 (42.4%) cases (P = 0.36). At the median OS was 8.5 (95% confidence interval [CI] 4.7–12.4) versus 13.7 (95% CI 10.0–16.5) months (P = 0.02), the 1‐, 2‐, and 3‐year survival rates were 27.5% versus 63.6%, 12.0% versus 20.0%, and 0.0% versus 16.0%, respectively. Serious adverse events in postoperative 30 days were 9.4% versus 28.6% (P = 0.11). Multivariate analysis revealed that CRS + HIPEC, CC0‐1, adjuvant chemotherapy ≥6 cycles were independent factors for OS benefit.

Conclusion

CRS + HIPEC could improve OS for CRC PC patients, with acceptable perioperative safety. J. Surg. Oncol 2014; 109:730–739. © 2013 The Authors. Journal of Surgical Oncology. Published by Wiley Periodicals, Inc.     

Clinical significance of SOD2 and GSTP1 gene polymorphisms in Chinese patients with gastric cancer

BACKGROUND:

Excessive reactive oxygen species (ROS) accumulation is a common phenomenon in carcinogenesis. However, the rationale behind ROS involvement in gastric cancer is unclear. In this study, the authors investigated the clinical significance of the single nucleotide polymorphisms (SNPs) of 2 ROS metabolic process‐related genes: superoxide dismutase 2 (SOD2) and glutathione S‐transferase π (GSTP1).

METHODS:

In total of 929 patients with gastric cancer who had definitive clinicopathologic and follow‐up data were collected. SOD2 reference SNP 4880 (rs4880) and GSTP1 rs1695 genotyping were examined in DNA samples extracted from paraffin‐embedded tumor tissue. Association of the 2 SNPs with each clinicopathologic feature was analyzed using the Pearson chi‐square test and the independent Student t test. Gastric cancer‐specific overall survival was analyzed using Kaplan‐Meier curves and log‐rank tests. Multivariate Cox regression analyses of these SNPs also were performed.

RESULTS:

The SOD2 rs4880 CT + CC genotypes were significantly associated with a high level of lymph node metastasis (P = .023), whereas the GSTP1 rs1695 GA + GG genotypes were significantly associated with larger tumor size (>5 cm long; P = .048). Kaplan‐Meier and Cox regression data indicated that the SOD2 rs4880 CT + CC genotypes alone (hazard ratio, 1.299; 95% confidence interval, 1.053‐1.603; P = .015) and the GSTP1 rs1695 GA + GG combined genotypes (hazard ratio, 1.496; 95% CI, 1.078‐2.074; P = .016) were independent predictors for overall survival.

CONCLUSIONS:

The current data, based on a large cohort (n = 929) of Chinese patients with gastric cancer, suggested that the presence of SOD2 rs4880 and GSTP1 rs1695 genotypes may contribute to cancer progression as well as tumor aggressiveness. The components of ROS metabolism pathways may be potential therapeutic targets for this aggressive malignancy. Cancer 2012. © 2012 American Cancer Society.     

MicroRNA-binding site SNPs in deregulated genes are associated with clinical outcome of non-small cell lung cancer

Background

Single-nucleotide polymorphisms (SNPs) in 3′-untranslated regions of cancer-related genes might affect regulation by microRNAs and contribute to cancer patients’ outcome.

Methods

We used public databases to identify SNPs within miRNA-binding sites in deregulated genes in non-small cell lung cancer (NSCLC). A total of 13 SNPs in 10 genes were included and genotyped by SNaPshot assay in 576 NSCLC patients. Associations between SNPs, overall survival (OS) and chemotherapy response were evaluated by Cox regression and logistic regression. We then examined the functionality of the significant polymorphisms.

Results

Two SNPs (TYMS rs2790 and MICA rs9266825) were significantly associated with OS. In the combined analysis, an increasing number of unfavorable loci was associated with a poorer prognosis (P for trend < 0.001) and patients having 2–3 unfavorable loci had a 1.61-fold elevated risk of death (95% confidence interval: 1.20–2.15), compared with those carrying 0–1 unfavorable loci. A significant effect of SNPs on platinum-based chemotherapy response was observed among 296 advanced NSCLC patients without surgical operation: rs2790, rs4246215 and rs1882. Further analysis using mRNA expression data from the HapMap suggested that these significant loci (FEN1 rs4246215, HDAC2 rs11391, MICA rs1882 and rs9266825) were closely associated with host genes expression. In vitro functional study for TYMS rs2790 was carried out. Luciferase assay showed a lower expression level for rs2790 G allele as compared with A allele, and the hsa-miR-1248 had an effect on modulation of TYMS gene.

Conclusion

Our data indicate that miRNA-binding site SNPs in deregulated genes may serve as candidate prognostic markers of NSCLC clinical outcome.     

Genetic variants in the integrin signaling pathway genes predict cutaneous melanoma survival

To identify genetic variants involved in prognosis of cutaneous melanoma (CM), we investigated associations of single nucleotide polymorphisms (SNPs) of genes in the integrin signaling pathway with CM survival by re‐analyzing a published genome‐wide association study (GWAS) from The University of Texas M.D. Anderson Cancer Center (MDACC) and then validated significant SNPs in another GWAS from Harvard University. In the MDACC study, 1,148 SNPs were significantly associated with CM‐specific survival (CMSS) (p ≤ 0.050 and false‐positive report probability ≤ 0.20), and nine SNPs were validated in the Harvard study (p ≤ 0.050). Among these, three independent SNPs (i.e., DOCK1 rs11018104 T > A, rs35748949 C > T and PAK2 rs1718404 C > T) showed a predictive role in CMSS, with an effect‐allele attributed adjusted hazards ratio [adjHR of 1.50 (95% confidence interval (CI) = 1.18‐1.90, p = 7.46E‐04), 1.53 (1.18‐1.97, 1.18E‐03) and 0.58 (0.45‐0.76, 5.60E‐05), respectively]. Haplotype analysis revealed that a haplotype carrying two risk alleles A‐T in DOCK1 was associated with the poorest survival in both MDACC (adjHR = 1.73, 95% CI = 1.19‐2.50, p = 0.004) and Harvard (adjHR = 1.95, 95% CI = 1.14‐3.33, p = 0.010) studies. In addition, patients with an increasing number of unfavorable genotypes (NUGs) for these three SNPs had a poorer survival. Incorporating NUGs with clinical variables showed a significantly improved ability to classify CMSS (AUC increased from 86.8% to 88.6%, p = 0.031). Genetic variants in the integrin signaling pathway may independently or jointly modulate the survival of CM patients. Further large, prospective studies are needed to validate these findings.     

Evaluation of genetic variants in association with colorectal cancer risk and survival in Asians

Genome‐wide association studies (GWAS) have identified over 40 genetic loci associated with colorectal cancer (CRC) risk. The association of single nucleotide polymorphisms (SNPs) at these loci with CRC risk and survival has not been adequately evaluated in East Asians. GWAS‐identified CRC risk variants were used to construct weighted genetic risk scores (GRSs). We evaluated these GRSs in association with CRC risk in 3,303 CRC cases and 3,553 controls using logistic regression models. Associations with overall and CRC‐specific survival were assessed in 731 CRC patients using Cox regression models. The association between the GRSs (overall and Asian‐specific) and CRC risk was approximately twofold (highest vs . lowest quintile), and the shape of the dose–response was linear (p _trend = 1.24 × 10^?13 and 3.02 × 10^?14 for overall GRS and Asian‐specific GRS, respectively). The association of the GRS with CRC risk was stronger among those with a family history of CRC (p _interaction = 0.007). Asian‐specific GRS using previously reported survival SNPs increased risk for mortality and the shape of the dose–response was linear for CRC‐specific and all‐cause mortality (p _trend = 0.01 and 0.006, respectively). Furthermore, the minor alleles of rs6983267 and rs1957636 were associated with worse CRC‐specific and overall survival. We show that GRSs constructed using GWAS‐identified common variants are strongly associated with CRC risk in Asians. We confirm previous findings for the possible association between some SNPs with survival, and provide evidence for two additional CRC risk variants that may be related to CRC survival.     

The role of polymorphisms in circadian pathway genes in breast tumorigenesis

Disruption of the circadian rhythm or biological clock, which is regulated by a number of clock genes, including circadian locomotor output cycles kaput (CLOCK), period genes (PERs), and cryptochrome genes (CRYs), is a risk factor for breast cancer. We hypothesized that genetic variation in these clock genes may influence breast cancer risk. To test this hypothesis, we designed a hospital-based study that included 1,538 breast cancer patients and 1,605 healthy controls. We genotyped subjects for five single nucleotide polymorphisms (SNPs) and a length variant of the circadian clock genes and evaluated their associations with breast cancer risk. These polymorphisms were determined by TaqMan allelic discrimination assays and the polymerase chain reaction-restriction fragment length polymorphism method. Univariate logistic regression analysis showed that polymorphisms of the CLOCK and CRY1 genes were associated with breast cancer risk. We found that carriers of the CLOCK CT and combined CT+TT genotypes had a significantly higher risk of breast cancer than carriers of the CC genotype (aOR = 1.35, 95% CI = 1.12-1.63 and aOR = 1.30, 95% CI = 1.09–1.56, respectively). Carriers of the CRY1 GT genotype had a decreased risk of breast cancer (aOR = 0.84, 95% CI = 0.71–0.99). We also observed a lower risk of breast cancer in carriers of the CRY2 CC genotype who were ER-positive than in those who were ER-negative (OR = 0.15, 95% CI = 0.04–0.67). When stratified by the CLOCK genotype, patients with the CLOCK CT/ CRY2 CC genotypes had significantly lower cancer risk than those with the GG genotype (aOR = 0.36, 95% CI = 0.14–0.95). Individuals carrying both the CLOCK CC and PER2 AA genotypes had an increased cancer risk (aOR = 2.28, 95% CI = 1.22–4.26). Our study suggests that genetic variants of the circadian rhythm regulatory pathway genes contribute to the differential risk of developing breast cancer in Chinese populations.     

Impact of BRAF mutation and microsatellite instability on the pattern of metastatic spread and prognosis in metastatic colorectal cancer

BACKGROUND:

It is hypothesized that BRAF mutant cancers represent a discrete subset of metastatic colorectal cancer (CRC) defined by poorer survival. This study investigates whether BRAF mutant CRC is further defined by a distinct pattern of metastatic spread and explores the impact of BRAF mutation and microsatellite instability (MSI) on prognosis in metastatic CRC.

METHODS:

By using prospective clinical data and molecular analyses from 2 major centers (Royal Melbourne Hospital and The University of Texas MD Anderson Cancer Center), patients with known BRAF mutation status were analyzed for clinical characteristics, survival, and metastatic sites.

RESULTS:

The authors identified 524 metastatic CRC patients where BRAF mutation status was known; 57 (11%) were BRAF mutant tumors. BRAF mutant tumors were significantly associated with right‐sided primary tumor, MSI, and poorer survival (median, 10.4 months vs 34.7 months, P < .001). A distinct pattern of metastatic spread was observed in BRAF mutant tumors, namely higher rates of peritoneal metastases (46% vs 24%, P = .001), distant lymph node metastases (53% vs 38%, P = .008), and lower rates of lung metastases (35% vs 49%, P = .049). In additional survival analyses, MSI tumors had significantly poorer survival compared with microsatellite stable tumors (22.1 months vs 11.1 months, P = .017), but this difference was not evident in the BRAF mutant population.

CONCLUSIONS:

The pattern of metastatic spread observed in this study further defines BRAF mutant CRC as a discrete disease subset. The authors demonstrated that, unlikely early stage disease, MSI is associated with poorer survival in metastatic CRC, although this is driven by its association with BRAF mutation. Cancer 2011;. © 2011 American Cancer Society.     

Functional polymorphisms in the NPAS2 gene are associated with overall survival in transcatheter arterial chemoembolization‐treated hepatocellular carcinoma patients

The functional abnormality of circadian regulation genes is involved in the development and progression of hepatocellular carcinoma (HCC). However, the association between functional single nucleotide polymorphisms (SNPs) in circadian gene NPAS2 and the overall survival of HCC patients treated with transcatheter arterial chemoembolization (TACE) has never been investigated. Six functional SNPs in the NPAS2 gene were genotyped using the Sequenom iPLEX genotyping system in a cohort of 448 unresectable Chinese patients with HCC treated with TACE. Multivariate Cox proportional hazards model and Kaplan–Meier curves were used for the prognosis analysis. We found that two SNPs, rs1053096 and rs2305160, in the NPAS2 gene showed significant associations with overall death risk in HCC patients in the recessive model (hazard ratio [HR] = 1.48; 95% confidence interval [CI], 1.13–1.94; P = 0.004) and in the dominant model (HR = 1.63; 95% CI, 1.29–2.07; P < 0.001), respectively. Moreover, we observed a cumulative effect of these two SNPs on HCC overall survival, indicating a significant trend of increasing death risk with increasing number of unfavorable genotypes (P for trend < 0.001). Compared with the patients without any unfavorable genotypes, the HRs for patients with one and two unfavorable genotypes were 1.41 (95% CI, 1.10–1.82; P = 0.007) and 2.09 (95% CI, 1.46–2.97, P < 0.001), respectively. The haplotype and diplotype analyses further characterized the association between NPAS2 genotype and survival of HCC patients. Our results for the first time suggest that NPAS2 gene polymorphisms may serve as an independent prognostic marker for HCC patients treated with TACE.     

Phosphorylated CXCR4 is associated with poor survival in adults with B-acute lymphoblastic leukemia

BACKGROUND:

CXC chemokine receptor 4 (CXCR4) is activated by phosphorylation (pCXCR4) and is essential for the migration of hematopoietic precursors to bone marrow. CXCR4 overexpression predicts a poor prognosis in patients with acute myeloid leukemia. Data regarding the prognostic impact of CXCR4 in patients with B‐acute lymphoblastic leukemia (B‐ALL) are sparse and limited to the pediatric population.

METHODS:

The authors analyzed CXCR4 and pCXCR4 expression in 54 adults with newly diagnosed B‐ALL. CXCR4 was assessed by flow cytometry (FC) and immunohistochemistry (IHC) using an anti‐CXCR4 antibody. pCXCR4 expression was assessed using an anti‐pCXCR4 antibody.

RESULTS:

The study group included 30 men and 24 women with a median age of 42 years (range, 17‐84 years). Philadelphia chromosome was present in 19 patients. The median follow‐up was 16 months (range, 17‐84 months). Forty‐nine patients had a complete response, and 12 patients relapsed with a median relapse free survival >120 weeks. Fifteen patients (28%) died with a median survival >125 weeks. CXCR4 detected by FC and IHC was highly correlated (P < .001). CXCR4 was not associated with clinical or laboratory findings or survival. In contrast, pCXCR4 was associated with higher leukocyte count (P = .006) and serum bilirubin level (P = .03). In multivariate analysis, pCXCR4 expression (P = .027), high serum creatinine level (P < .01), presence of the Philadelphia chromosome (P = .017), and late clinical response (P < .001) were associated with worse overall survival.

CONCLUSIONS:

The current results indicated that detection of the activated form of CXCR4, pCXCR4, provides independent prognostic information in adult patients with B‐ALL. Cancer 2011;. © 2011 American Cancer Society.