Association of excision repair cross-complementation group 1 (ERCC1) gene expression (GE) with outcome in stage II-III esophageal adenocarcinoma (EA) patients treated with preoperative platinum-based chemoradiation (CRT) in a phase II cooperative study (SWOG 0356)

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Background: Preoperative platinum-based CRT for operable esophageal cancer has improved overall survival (OS) compared to surgery alone. The phase II SWOG 0356 trial designed to test oxaliplatin (OXP) plus infusion 5-fluorouracil (5-FU) and external beam radiation prior to surgery for potentially curable EA has produced promising centrally confirmed complete pathologic response (pCR) rate (28.3%). After surgery patients were given a second cycle of OXP and 5FU. 2-year OS was 54.2%. However, treatment efficacy may be significantly compromised as a result of interindividual variations. We tested whether intratumoral GE levels in drug metabolism (DPD, GSTPi, TS and TP) and DNA repair (ERCC1 and XPD) predicted clinical outcome (CO). We also tested whether specific pattern of 12 polymorphisms in 8 genes (drug metabolism (GSTP, MTHFR and TS) and DNA repair (ERCC1, RAD51, XPD, XRCC1 and XRCC3)) predicted CO.

Methods: A total of 90 patients from the SWOG 0356 study were eligible for the molecular correlative study. mRNA was extracted from laser-capture-microdissected tumor tissue. After cDNA was prepared by reverse transcription, quantitation of the candidate genes and an internal reference gene (ß-actin) was performed using a fluorescence-based real-time detection method (TaqMan). Established GE cutoffs were tested (ERCC1 <1.7 x 10-3; TS <4.0 x 10-3). DNA was extracted from blood and genotyped using PCR-RFLP techniques.

Results: In univariate analysis, we found ERCC1 GE levels to be significantly associated with progression-free survival (PFS) and OS. Patients with high ERCC1 GE levels had worse 2-year PFS (17 vs 67%, p=0.004) and 2-year OS (37 vs 72%, p=0.04) compared to low GE levels. ERCC1 GE levels were not associated with pCR. All the other GE levels tested did not show significant association with CO. None of the tested polymorphisms showed any association with CO.

Conclusions: Our data suggest that GE levels of ERCC1 may help to identify patients with stage II-III EA likely to experience longer survival when treated with preoperative OXP-based CRT.

No significant financial relationships to disclose.

Use of genetic variants in formyl peptide receptor 2 (FPR2) to predict tumor recurrence in stage II colon cancer

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Background: The formyl peptide receptor (FPR) is a G-protein-coupled receptor (GPCR) that mediates chemotaxis of phagocytic leucocytes induced by bacterial and host-derived chemotactic peptides. Recent studies found that it is selectively expressed in highly malignant gliomas and contributes to tumor growth and angiogenesis by mediating tumor cell chemotaxis, proliferation and production of chemokines and VEGF. Previously we demonstrated that polymorphisms in the VEGF pathway predict tumor recurrence in adjuvant colon cancer. Here we tested the hypothesis that two genetic variants in the FPR2 gene (rs17834679 and rs17694990) may predict tumor recurrence in a cohort of adjuvant colon cancer patients.

Methods: Between 1992 and 2007, blood samples were obtained from 234 adjuvant colon caner patients (109 with stage II and 125 with stage III) at the USC medical facilities. Genomic DNA was extracted from peripheral blood and two potentially functional genotypes (rs17834679 and rs17694990) within the FPR2 gene were determined utilizing the PCR-RFLP technique. The median follow-up was 4.4 years (range: 0.3- 16.8). Ninety of 234 patients (38.5%) developed tumor recurrence with a 3-year probability of 0.34 ± 0.05.

Results: In multivariable Cox proportional hazards regression analysis, FPR2 polymorphism rs17834679 was significantly associated with time to tumor recurrence (TTR) in stage II colon cancer (adjusted P = 0.027). Patients with CC genotype were at greatest risk of developing tumor recurrence (adjusted hazard ratio [HR]: 2.819 [95%CI: 1.127-7.051]) compared to those with GC and GG genotypes. In the dominant inheritance model, patients with any G allele had longer TTR (16.8 years+, median was not reached) compared to those with CC genotype (median TTR 5.4 years [95%CI: 3.2-10.7]; p=0.007, log-rank test). There are no significantly associations between FPR2 polymorphisms and TTR in stage III colon cancer.

Conclusions: Polymorphisms in the FPR2 gene may serve as molecular markers for tumor recurrence in stage II colon cancer, indicating that the analysis of genetic variants of FPR2 may help to identify patient subgroups at high risk for tumor recurrence.

No significant financial relationships to disclose.

Umbilical vein testosterone in female infants born to mothers with polycystic ovary syndrome is elevated to male levels

The aetiology of polycystic ovary syndrome (PCOS) is poorly understood, but an intrauterine hyperandrogenic environment has been implicated. This study was designed to assess whether the female offspring of mothers with PCOS are exposed to raised levels of testosterone (T) in utero. In this case-control study, three groups of pregnant women were recruited from the labour ward: PCOS women with a female baby (n = 10, PCOS girls); control women with a female baby (n = 20, control girls) and control women with a male baby (n = 10, control boys). Maternal and umbilical vein (UV) blood was assayed for T levels. UV T in PCOS girls was significantly raised, compared with control girls (p < 0.012). The difference in UV T between PCOS girls and control boys was not significant (p < 0.254). This is the first demonstration of a hyperandrogenic in utero environment in PCOS pregnancies; UV T in female infants is raised to male levels.

Mutations in fibrillin-1 cause congenital scleroderma: stiff skin syndrome

The predisposition for scleroderma, defined as fibrosis and hardening of the skin, is poorly understood. We report that stiff skin syndrome (SSS), an autosomal dominant congenital form of scleroderma, is caused by mutations in the sole Arg-Gly-Asp sequence-encoding domain of fibrillin-1 that mediates integrin binding. Ordered polymers of fibrillin-1 (termed microfibrils) initiate elastic fiber assembly and bind to and regulate the activation of the profibrotic cytokine transforming growth factor-beta (TGFbeta). Altered cell-matrix interactions in SSS accompany excessive microfibrillar deposition, impaired elastogenesis, and increased TGFbeta concentration and signaling in the dermis. The observation of similar findings in systemic sclerosis, a more common acquired form of scleroderma, suggests broad pathogenic relevance.

Gender-related survival differences associated with polymorphic variants of estrogen receptor-β (ERβ) in patients with metastatic colon cancer

Estrogen replacement therapy in women has demonstrated a protective effect in the development of colonic carcinomas. Gender-related differences in the development of colonic carcinomas have also been reported. Estrogen receptor beta (ERβ) is expressed in colon carcinomas and has demonstrated prognostic value in colon cancer patients. This study investigated an ERβ 3’ non-coding polymorphism associated with transcriptional activity to determine clinical outcome in patients with metastatic colon cancer. Genomic DNA from 318 metastatic colon cancer patients, 177 males and 141 females, were collected from 1992 to 2003. These patients were analyzed for CA repeat polymorphism of the ERβ gene. Gender-related survival differences were associated with an ERβ (CA)_n repeat polymorphism (P for interaction=0.003, the likelihood ratio test). Female patients with any short <22 (CA)_n repeat alleles had shorter overall survival compared to female patients that had both long ≥22 (CA)_n repeat alleles. In the male patients the opposite overall survival difference was found. This study supports the role of an ERβ (CA)_n repeat polymorphism as a prognostic marker in metastatic colon cancer; however, this prognostic factor had opposite implications based on gender.

Cost of fractures commonly associated with osteoporosis in a managed-care population

OBJECTIVE

To examine direct costs of hip, vertebral, and non-hip non-vertebral (NHNV) fractures, and to estimate the rate of osteoporosis (OA) diagnosis and treatment in the fracture population.

METHODS

Subjects ≥ 45 years with a new hip, vertebral, or NHNV fragility (closed) fracture between June 30, 2002 and June 30, 2006 were studied retrospectively. All-cause and fracture-specific medical costs were calculated from medical claims in the 12-month baseline and follow-up periods. Total healthcare costs included pharmacy and medical costs. Diagnosis for OA and OA treatment were identified in both the baseline and follow-up period from diagnosis codes on medical claims for OA, and from pharmacy claims for treatment. Analyses were performed separately for commercial (COM) and Medicare Advantage (MA) populations and stratified by fracture type. Generalized linear models were estimated for total follow-up healthcare cost.

RESULTS

The study sample included 36,521 COM and 10,160 MA subjects. Hip fracture subjects had the highest follow-up medical costs in unadjusted and adjusted analyses (COM: mean $35,898; median $22,945; MA: mean $32,919; median $26,047). Follow-up costs were much higher than baseline costs. Fracture-related costs accounted for a large proportion of follow-up medical costs. Although rates of osteoporosis diagnosis and treatment increased from baseline to follow-up, the majority of both COM and MA subjects had no evidence of osteoporosis diagnosis or treatment in either period.

CONCLUSIONS

Despite limitations of this study, including conventional generalizability issues, and sensitivity and specificity of claims-based diagnoses, results are consistent with other research and provide compelling results of substantial cost burden of fractures related to osteoporosis. Low rates of osteoporosis diagnosis and treatment among patients with costly fragility fractures underscore the opportunity for managed care organizations to initiate comprehensive disease management programs in osteoporosis.