Impact of IGF-I and CYP19 gene polymorphisms on the survival of patients with metastatic prostate cancer

Targeting Sphingosine 1-Phosphate Metabolism as a Therapeutic Avenue for Prostate Cancer

Prostate cancer (PC) is the second most common cancer in men worldwide. More than 65% of men diagnosed with PC are above 65. Patients with localized PC show high long-term survival, however with the disease progression into a metastatic form, it becomes incurable, even after strong radio- and/or chemotherapy. Sphingosine 1-phosphate (S1P) is a bioactive lipid that participates in all the steps of oncogenesis including tumor cell proliferation, survival, migration, invasion, and metastatic spread. The S1P-producing enzymes sphingosine kinases 1 and 2 (SK1 and SK2), and the S1P degrading enzyme S1P lyase (SPL), have been shown to be highly implicated in the onset, development, and therapy resistance of PC during the last 20 years. In this review, the most important studies demonstrating the role of S1P and S1P metabolic partners in PC are discussed. The different in vitro, ex vivo, and in vivo models of PC that were used to demonstrate the implication of S1P metabolism are especially highlighted. Furthermore, the most efficient molecules targeting S1P metabolism that are under preclinical and clinical development for curing PC are summarized. Finally, the possibility of targeting S1P metabolism alone or combined with other therapies in the foreseeable future as an alternative option for PC patients is discussed. Research Strategy: PubMed from INSB was used for article research. First, key words "prostate & sphingosine" were used and 144 articles were found. We also realized other combinations of key words as "prostate cancer bone metastasis" and "prostate cancer treatment". We used the most recent reviews to illustrate prostate cancer topic and sphingolipid metabolism overview topic.

Emerging Role of IGF-1 in Prostate Cancer: A Promising Biomarker and Therapeutic Target

Prostate cancer (PCa) is a highly heterogeneous disease driven by gene alterations and microenvironmental influences. Not only enhanced serum IGF-1 but also the activation of IGF-1R and its downstream signaling components has been increasingly recognized to have a vital driving role in the development of PCa. A better understanding of IGF-1/IGF-1R activity and regulation has therefore emerged as an important subject of PCa research. IGF-1/IGF-1R signaling affects diverse biological processes in cancer cells, including promoting survival and renewal, inducing migration and spread, and promoting resistance to radiation and castration. Consequently, inhibitory reagents targeting IGF-1/IGF-1R have been developed to limit cancer development. Multiple agents targeting IGF-1/IGF-1R signaling have shown effects against tumor growth in tumor xenograft models, but further verification of their effectiveness in PCa patients in clinical trials is still needed. Combining androgen deprivation therapy or cytotoxic chemotherapeutics with IGF-1R antagonists based on reliable predictive biomarkers and developing and applying novel agents may provide more desirable outcomes. This review will summarize the contribution of IGF-1 signaling to the development of PCa and highlight the relevance of this signaling axis in potential strategies for cancer therapy.

Association of CYP19A1 Gene, Plasma Zinc, and Urinary Zinc with the Risk of Type 2 Diabetes Mellitus in a Chinese Population

To explore the effects of CYP19A1 gene polymorphisms, plasma zinc, and urinary zinc levels and their interactions on type 2 diabetes mellitus (T2DM) in residents of Gongcheng County, Guangxi, China. The case-control study was used for the investing. The MassARRAY System was applied to genotype the CYP19A1 genes rs752760, rs10046, rs10459592, and rs700518 in 540 study subjects. Plasma and urinary zinc concentrations were measured by inductively coupled plasma mass spectrometry (ICP-MS). Conditional logistic regression showed that rs752760 and plasma zinc were associated with T2DM risks with ORs of 0.593 (95% CI: 0.371-0.948) and 0.563 (95% CI: 0.356-0.889), respectively. Unconditional logistic regression analysis showed an association between urinary zinc levels and the risk of T2DM as well, with an OR of 0.352 (95% CI: 0.212-0.585). The results of the multiplicative interaction model showed that the rs752760 T allele was associated with a significantly reduced risk of T2DM with moderate/low plasma zinc levels, with ORs of 0.340 (95% CI: 0.161-0.715) and 0.583 (95% CI: 0.346-0.981), respectively, and the rs752760 T allele was also associated with a significantly decreased risk of T2DM with moderate/low urinary zinc levels, with ORs of 0.358 (95% CI: 0.201-0.635) and 0.321 (95% CI: 0.183-0.562), respectively. CYP19A1 rs752760 T allele and moderate/low plasma/urinary zinc levels reduce the risk of T2DM.

Three-month early change in prostate-specific antigen levels as a predictive marker for overall survival during hormonal therapy for metastatic hormone-sensitive prostate cancer

Objective

To date, there are no useful markers for predicting the prognosis of metastatic hormone-sensitive prostate cancer (mHSPC). We evaluated the effect of early changes in prostate-specific antigen (PSA) levels after androgen deprivation therapy (ADT) on castration-resistant prostate cancer (CRPC) progression and overall survival (OS) in mHSPC patients.

Results

In 71 primary mHSPC patients treated with ADT, the median times to CRPC and OS were 15 months and 92 months, respectively. In multivariate analysis, a Gleason score of ≥ 8 (p = 0.004), an extent of disease value (EOD) of ≥ 2 (p = 0.004), and a 3-month PSA level > 1% of the pretreatment level (p = 0.017) were independent predictors of shorter time to CRPC. The area under the receiver operating characteristic curve was feasible at 0.822. A 3-month PSA level > 1% of the pretreatment level was an independent predictor of OS (p = 0.004). Three factors were independent predictors of shorter time to CRPC. A 3-month PSA level > 1% of the pretreatment level correlated with a poor prognosis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13104-021-05641-5.

Changes in conditional net survival and dynamic prognostic factors in patients with newly diagnosed metastatic prostate cancer initially treated with androgen deprivation therapy

BACKGROUND

The purpose of this study was to identify predictive factors associated with conditional net survival in patients with metastatic hormone-naive prostate cancer (mHNPC) initially treated with androgen deprivation therapy (ADT).

METHODS

At nine hospitals in Tohoku, Japan, the medical records of 605 consecutive patients with mHNPC who initially received ADT were retrospectively reviewed. The Pohar Perme estimator was used to calculate conditional net cancer-specific survival (CSS) and overall survival (OS) for up to 5 years subsequent to the diagnosis. Using multiple imputation, proportional hazard ratios for conditional CSS and OS were calculated with adjusted Cox regression models.

RESULTS

During a median follow up of 2.95 years, 208 patients died, of which 169 died due to progressive prostate cancer. At baseline, the 5-year CSS and OS rates were 65.5% and 58.2%, respectively. Conditional 5-year net CSS and OS survival gradually increased for all the patients. In patients given a 5-year survivorship, the conditional 5-year net CSS and OS rates improved to 0.906 and 0.811, respectively. Only the extent of disease score (EOD) ≥2 remained a prognostic factor for CSS and OS up to 5 years; as survival time increased, other variables were no longer independent prognostic factors.

CONCLUSIONS

The conditional 5-year net CSS and OS in patients with mHNPC gradually increased; thus, the risk of mortality decreased with increasing survival. The patient's risk profile changed over time. EOD remained an independent prognostic factor for CSS and OS after 5-year follow-up. Conditional net survival can play a role in clinical decision-making, providing intriguing information for cancer survivors.

Polycystic ovary syndrome (PCOS) and genetic predisposition: A review article

Polycystic ovary syndrome (PCOS) is a heterogeneous condition which is related to an endocrine reproductive disorder of females. It affects females of 18-44 age. The persistent hormonal disbalance leads to the complexities such as numerous cysts, an irregular menstrual cycle that ultimately leads to infertility among females. Many candidate genes have been identified to be one of the causes of PCOS. Different studies have been carried out to find the genetic correlation of PCOS. It is essential to carry out such studies that identify the clear cause of PCOS and its genetic association and hormonal disbalance. This review has highlighted different genes and their correlation with PCOS that leads to hormonal disbalance. Yet not in-depth but an attempt to study the genetic predisposition of PCOS.

The impact of genetic polymorphism on CYP19A1 in androgen-deprivation therapy among Japanese men

PURPOSE

Inadequate suppression of testosterone during androgen-deprivation therapy impairs its efficacy. This study investigated the significance of genetic polymorphism in CYP19A1, which encodes aromatase that catalyzes androgens into estrogens, among men treated with primary ADT for metastatic prostate cancer.

METHODS

This study included 80 Japanese patients with metastatic prostate cancer whose serum testosterone levels during ADT were available. The association of CYP19A1 gene polymorphism (rs1870050) with clinicopathological parameters including serum testosterone levels during ADT as well as progression-free survival and overall survival was examined.

RESULTS

Serum testosterone levels during ADT of men carrying homozygous wild-type (AA) in the CYP19A1 gene [median (interquartile range); 11.6 (8.3-20.3) ng/dl] were higher than those in men carrying the heterozygous/homozygous variant (AC/CC) [median (interquartile range); 10.0 (6.4-12.8) ng/dl]. When adjusted by Gleason score, initial PSA, M-stage and serum testosterone level during ADT, heterozygous/homozygous variant (AC/CC) in the CYP19A1 gene was associated with a lower risk of progression to castration resistance [hazard ratio (95% confidence interval), 0.53 [0.29-0.92], p = 0.025], but not to any-cause death [hazard ratio (95% confidence interval), 0.74 [0.36-1.49], p = 0.40].

CONCLUSIONS

These findings suggest that genetic variation in CYP19A1 (rs1870050) might affect the prognosis of patients with metastatic prostate cancer when treated with ADT by regulating serum testosterone levels.

LIMK2 acts as an oncogene in bladder cancer and its functional SNP in the microRNA-135a binding site affects bladder cancer risk

LIM kinases modulate multiple aspects of cancer development, including cell proliferation and survival. As the mechanisms of LIMK-associated tumorigenesis are still unclear, we analyzed the tumorigenic functions of LIM kinase 2 (LIMK2) in human bladder cancer (BC) and explored whether the newly identified LIMK2 3´-UTR SNP rs2073859 (G-to-A allele) is correlated with clinical features. Expression levels of LIMK2 in 38 human BC tissues and eight cell lines were examined using quantitative real-time PCR and immunohistochemistry. LIMK2 was overexpressed in most BC tissues (27/38, 71%) and BC-derived cell lines (6/8), and was more frequently overexpessed in high-grade than low-grade BC (80% vs. 47%). The effects of LIMK2 on BC cell proliferation, survival and migration, were studied by overexpression and RNA interference approaches in vitro and in vivo. LIMK2 overexpression promoted proliferation, migration and invasion of BC cells, while LIMK2 depletion inhibited cell invasion and viability and induced growth arrest in vitro and in vivo. PCR-Restriction Fragment Length Polymorphism (RFLP) was used to genotype LIMK2 SNP rs2073859 and multivariate logistic regression applied to assess the relationship between allele frequency and clinical features in 139 BC patients. Functional analyses localized SNP rs2073859 within the microRNA-135a seed-binding region and revealed significantly lower LIMK2 G allele expression. The frequency of A genotypes (AG + AA) was higher in the BC group than normal controls and correlated with risks of high-grade and high-stage BC. In conclusion, LIMK2 may function as an oncogene in human BC, while allele-specific regulation by microRNA-135a may influence disease risk.

Impact of early changes in serum biomarkers following androgen deprivation therapy on clinical outcomes in metastatic hormone-sensitive prostate cancer

Background

Less evidence is known about the role of early changes in serum biomarker after androgen deprivation therapy (ADT) in patients with metastatic hormone-sensitive prostate cancer (mHSPC). Here we evaluated the impact of pre-treatment prognostic factors and early changes in serum biomarkers on prostate specific antigen (PSA) progression-free and overall survival rates in mHSPC.

Methods

We retrospectively reviewed the medical records of 60 mHSPC patients (median age 72 years) treated with ADT whose laboratory data at baseline and following 12 weeks were available.

Results

Forty-four patients (73%) had PSA progression and 27 patients (45.0%) died during a median follow-up of 34 months. The multivariable Cox hazard model demonstrated that a log-transformed baseline PSA level (p = 0.003) and an extent of bone disease (EOD) score of ≥3 (p = 0.004) were statistically associated with an increased risk for PSA progression whereas one unit increase in a log-transformed PSA change (baseline-12 weeks) was associated with a decreased risk for PSA progression (p = 0.004). For overall survival, a high level of alkaline phosphatase (ALP) at 12 weeks was associated with increased risk (p = 0.030) whereas a one-unit increase in the log-transformed PSA change was associated with decreased risk (p = 0.001).

Conclusions

An increased level of PSA at baseline, or an EOD score of ≥3 may be a good predictor of PSA progression, and a high level of ALP at 12 weeks may be a risk predictor of death. A larger decline in PSA at 12 weeks from the baseline was associated with both PSA progression-free and overall survival time. Early changes in serum biomarkers may be useful in predicting poor outcomes in patients with mHSPC who are initially treated with ADT.

Gene polymorphisms in antioxidant enzymes correlate with the efficacy of androgen-deprivation therapy for prostate cancer with implications of oxidative stress

Background

Oxidative stress mitigated by antioxidant enzymes is thought to be involved in the progression to castration-resistant prostate cancer (CRPC) during androgen-deprivation therapy (ADT). This study investigated the association between genetic variations in antioxidant enzymes and the efficacy of ADT as well as its biological background.

Patients and methods

The non-synonymous or promoter-locating polymorphisms of antioxidant enzymes were examined as well as the time to CRPC progression and overall survival in 104 and 92 patients treated with ADT for metastatic and non-metastatic prostate cancer, respectively. In addition, intracellular reactive oxygen species and expression levels of antioxidant enzymes were examined in castration-resistant and enzalutamide-resistant cells.

Results

In metastatic prostate cancer, the AG/GG allele in GSTM3 rs7483 and CT/TT allele in CAT rs564250 were associated with a significantly lower risk of progression to CRPC and all-cause death compared with homozygotes of the major AA allele (hazard ratio [HR]; [95% confidence interval (CI)], 0.55 [0.34-0.86], P = 0.0086) and CC allele (HR; [95% CI], 0.48 [0.24-0.88], P = 0.016), respectively. On multivariate analyses, only GSTM3 rs7483 was associated with significant progression risk (AG/GG versus AA; HR; [95% CI], 0.45 [0.25-0.79], P = 0.0047) even after Bonferroni adjustment. In non-metastatic prostate cancer, the AG/GG allele in GSTM3 rs7483 was associated with a significantly lower risk of progression to CRPC (HR; [95% CI], 0.35 [0.10-0.93], P = 0.034) and all-cause death (HR; [95% CI], 0.26 [0.041-0.96], P = 0.043) compared with the AA allele. Intracellular reactive oxygen species levels were increased, accompanied with augmented GSTM3 expression in both castration-resistant and enzalutamide-resistant cells.

Conclusions

Differential activity of antioxidant enzymes caused by the polymorphism in GSTM3 may contribute to resistance to hormonal therapy through oxidative stress. The GSTM3 rs7483 polymorphism may be a promising biomarker for prostate cancer patients treated with ADT.

Does milk intake promote prostate cancer initiation or progression via effects on insulin-like growth factors (IGFs)? A systematic review and meta-analysis

PURPOSE

To establish whether the association between milk intake and prostate cancer operates via the insulin-like growth factor (IGF) pathway (including IGF-I, IGF-II, IGFBP-1, IGFBP-2, and IGFBP-3).

METHODS

Systematic review, collating data from all relevant studies examining associations of milk with IGF, and those examining associations of IGF with prostate cancer risk and progression. Data were extracted from experimental and observational studies conducted in either humans or animals, and analyzed using meta-analysis where possible, with summary data presented otherwise.

RESULTS

One hundred and seventy-two studies met the inclusion criteria: 31 examining the milk-IGF relationship; 132 examining the IGF-prostate cancer relationship in humans; and 10 animal studies examining the IGF-prostate cancer relationship. There was moderate evidence that circulating IGF-I and IGFBP-3 increase with milk (and dairy protein) intake (an estimated standardized effect size of 0.10 SD increase in IGF-I and 0.05 SD in IGFBP-3 per 1 SD increase in milk intake). There was moderate evidence that prostate cancer risk increased with IGF-I (Random effects meta-analysis OR per SD increase in IGF-I 1.09; 95% CI 1.03, 1.16; n = 51 studies) and decreased with IGFBP-3 (OR 0.90; 0.83, 0.98; n = 39 studies), but not with other growth factors. The IGFBP-3 -202A/C single nucleotide polymorphism was positively associated with prostate cancer (pooled OR for A/C vs. AA = 1.22; 95% CI 0.84, 1.79; OR for C/C vs. AA = 1.51; 1.03, 2.21, n = 8 studies). No strong associations were observed for IGF-II, IGFBP-1 or IGFBP-2 with either milk intake or prostate cancer risk. There was little consistency within the data extracted from the small number of animal studies. There was additional evidence to suggest that the suppression of IGF-II can reduce tumor size, and contradictory evidence with regards to the effect of IGFBP-3 suppression on tumor progression.

CONCLUSION

IGF-I is a potential mechanism underlying the observed associations between milk intake and prostate cancer risk.

Polymorphisms in androgen metabolism genes AR, CYP1B1, CYP19, and SRD5A2and prostate cancer risk and aggressiveness in Bulgarian patients

BACKGROUND/AIM

The aim of our study was to elucidate the role of polymorphisms in AR, CYP1B1, CYP19, and SRD5A2 genes for prostate cancer (PC) development in Bulgarian patients.

MATERIALS AND METHODS

We genotyped 246 PC patients and 261 controls (155 with benign prostate hyperplasia and 107 healthy population controls) using direct sequencing, PCR-RFLP, SSCP, and fragment analysis.

RESULTS

The allele and genotype frequencies of most of the studied variants did not differ significantly between cases and controls. Increased frequencies of the C/C genotype and C allele of rs1056837 in CYP1B1, and genotype 7/8 of the (TTTA)n repeat polymorphism in CYP19, were observed in patients in comparison with controls.The 8/9 and the 7/12 genotypes of (TTTA)n in CYP19 showed suggestive evidence for association with decreased prostate cancer risk and the risk for aggressive disease, respectively. The haplotype analysis revealed 2 CYP1B1 haplotypes associated with PC risk reduction.

CONCLUSION

Some CYP1B1 haplotypes and genotypes of the CYP19 (TTTA)n repeat appeared to be associated with disease risk or aggressiveness in Bulgarian PC patients. In contrast, the SRD5A2 polymorphisms (V89L and (TA)n repeat), the CAG repeat in AR, and the Arg264Cys variant in CYP19A1 are most likely not implicated in prostate carcinogenesis.

Polymorphisms of Estrogen Metabolism-Related Genes and Prostate Cancer Risk in Two Populations of African Ancestry

Background

Estrogens are thought to play a critical role in prostate carcinogenesis. It has been suggested that polymorphisms of genes encoding enzymes involved in estrogen metabolism are risk factors for prostate cancer. However, few studies have been performed on populations of African ancestry, which are known to have a high risk of prostate cancer.

Objective

We investigated whether functional polymorphisms of CYP17, CYP19, CYP1B1, COMT and UGT1A1 affected the risk of prostate cancer in two different populations of African ancestry.

Methods

In Guadeloupe (French West Indies), we compared 498 prostate cancer patients and 565 control subjects. In Kinshasa (Democratic Republic of Congo), 162 prostate cancer patients were compared with 144 controls. Gene polymorphisms were determined by the SNaPshot technique or short tandem repeat PCR analysis. Logistic regression was used to estimate adjusted odds ratios (OR) and 95% confidence intervals (CI).

Results

The AA genotype and the A allele of rs4680 (COMT) appeared to be inversely associated with the risk of prostate cancer in adjusted models for both Afro-Caribbean and native African men. For the A allele, a significant inverse association was observed among cases with low-grade Gleason scores and localized clinical stage, in both populations.

Conclusions

These preliminary results support the hypothesis that polymorphisms of genes encoding enzymes involved in estrogen metabolism may modulate the risk of prostate cancer in populations of African ancestry.

Androgens and androgen receptor signaling in prostate tumorigenesis

Androgens and androgen receptor (AR) signaling are necessary for prostate development and homeostasis. AR signaling also drives the growth of nearly all prostate cancer cells. The role of androgens and AR signaling has been well characterized in metastatic prostate cancer, where it has been shown that prostate cancer cells are exquisitely adept at maintaining functional AR signaling to drive cancer growth. As androgens and AR signaling are so intimately involved in prostate development and the proliferation of advanced prostate cancer, it stands to reason that androgens and AR are also involved in prostate cancer initiation and the early stages of cancer growth, yet little is known of this process. In this review, we summarize the current state of knowledge concerning the role of androgens and AR signaling in prostate tissue, from development to metastatic, castration-resistant prostate cancer, and use that information to suggest potential roles for androgens and AR in prostate cancer initiation.

Insulin-like growth factor receptor polymorphism defines clinical outcome in estrogen receptor-positive breast cancer patients treated with tamoxifen

Compelling evidence points to a key role for insulin-like growth factor 1 (IGF1) signaling in breast cancer development and progression. In addition, IGF1 receptor (IGF1R) expression has been correlated and functionally linked with estrogen receptor (ER) signaling. Recent translational studies support a cross talk between IGF1R and ERα at different levels and data suggest enhanced IGF1R signaling as a causative mechanism of tamoxifen (TAM) resistance. We tested whether functional germline variations in the IGF pathway are associated with clinical outcome in ER-positive primary invasive breast cancer patients, who were treated with surgery and adjuvant TAM. Tissue samples of 222 patients with ER+ primary invasive breast cancer, who had undergone surgery at Charing Cross Hospital, London, UK between 1981 and 2003, were analyzed. Genomic DNA was extracted from formalin-fixed, paraffin-embedded tissue samples and six functional IGF1 pathway polymorphisms were analyzed using direct DNA sequencing and PCR-restriction fragment length polymorphism. In multivariable analysis, patients with primary invasive breast cancer carrying IGF1R_rs2016347 G allele had a significantly increased risk of early tumor progression (hazard ratio (HR) 2.01; adjusted P=0.004) and death (HR 1.84; adjusted P=0.023) compared with patients carrying G/T or T/T, independent of established clinicopathological determinants. This association remained significant after adjusting for multiple testing. In addition, we were able to demonstrate that IRS1_rs1801123 and IGFBP3_rs2854744 were significantly associated with lymph node involvement and tumor size, respectively. We provide the first evidence for IGF1R_rs2016347 as an independent prognostic marker for ER+ breast cancer patients treated with TAM and support a rational for combined treatment strategies.

Distinct cancer-specific survival in metastatic prostate cancer patients classified by a panel of single nucleotide polymorphisms of cancer-associated genes

Individual genetic variations may have a significant influence on the survival of metastatic prostate cancer (PCa) patients. We aimed to identify target genes and their variations involved in the survival of PCa patients using a single nucleotide polymorphism (SNP) panel. A total of 185 PCa patients with bone metastasis at the initial diagnosis were analyzed. Germline DNA in each patient was genotyped using a cancer SNP panel that contained 1,421 SNPs in 408 cancer-related genes. SNPs associated with survival were screened by a log-rank test. Fourteen SNPs in 6 genes, XRCC4, PMS1, GATA3, IL13, CASP8, and IGF1, were identified to have a statistically significant association with cancer-specific survival. The cancer-specific survival times of patients grouped according to the number of risk genotypes of 6 SNPs selected from the 14 SNPs differed significantly (0-1 v. 2-3 v. 4-6 risk genotypes; P = 7.20 × 10(-8)). The high-risk group was independently associated with survival in a multivariate analysis that included conventional clinicopathological variables (P = 0.0060). We identified 14 candidate SNPs in 6 cancer-related genes, which were associated with poor survival in patients with metastatic PCa. A panel of SNPs may help predict the survival of those patients.

Insulin-like growth factor-1 genotypes and haplotypes influence the survival of prostate cancer patients with bone metastasis at initial diagnosis

Background

The insulin-like growth factor-1 (IGF-1) plays an important role in growth of prostate cancer (PCa) cells and facilitating the development and progression of PCa. This study aimed to evaluate the association of polymorphisms in three linkage disequilibrium (LD) blocks of the IGF-1 on the survival of metastatic PCa patients.

Methods

A total of 215 patients with bone metastases at initial presentation were included in this study. The cytosine-adenine (CA) repeat polymorphism and rs12423791 were selected as representative polymorphisms in the LD blocks 1 and 2, respectively. Haplotype in the LD block 3 was analyzed using two tag single nucleotide polymorphisms (SNPs), rs6220 and rs7136446. Cancer-specific survival rate was estimated from the Kaplan-Meier curve, and the survival data were compared using the log-rank test.

Results

Cancer-specific survival was significantly associated with the CA repeat polymorphism, rs12423791, and rs6220 (P = 0.013, 0.014, and 0.014, respectively). Although rs7136446 had no significant association with survival, the haplotype in the LD block 3 was significantly associated with cancer-specific survival (P = 0.0003). When the sum of the risk genetic factors in each LD block (19-repeat allele, C allele of rs12423791, or C-T haplotype) was considered, patients with all the risk factors had significantly shorter cancer specific-survival than those with 0–2 risk factors (P = 0.0003).

Conclusions

Polymorphisms in the IGF-1, especially a haplotype in the LD block 3, are assumed to be genetic markers predicting the outcome of metastatic PCa.

Association of a common genetic variant of the IGF-1 gene with event-free survival in patients with HER2-positive breast cancer

PURPOSE

Insulin-like growth factor 1 (IGF-1) stimulates mitosis and inhibits apoptosis. High circulating IGF-1 levels are linked with an increased risk of colorectal and breast cancer. Recently, IGF-1 single nucleotide polymorphisms (SNPs), especially variant rs2946834, have been associated with poor clinical outcome in patients with colorectal cancer. In the present study, we aimed to investigate the influence of IGF1 polymorphisms associated with IGF-1 plasma levels on event-free survival in patients with HER2-positive breast cancer.

METHODS

The present study included 161 consecutive white patients with HER2-positive breast cancer. Event-free survival was calculated as the time from cancer diagnosis to either relapse or death from any cause. Genomic DNA was extracted from archived formalin-fixed paraffin-embedded tumor tissue samples; five IGF-1 polymorphisms (rs2946834, rs6220, rs1520220, rs5742694, and rs5742678), all associated with IGF-1 levels, were genotyped by SNaPshot assays.

RESULTS

Kaplan-Meier analysis showed a poorer clinical outcome for carriers of the rare allele of SNP rs2946834 (log-rank test, p = 0.020). Concordantly, in univariate Cox regression analyses, the rare allele of SNP rs2946834 was significantly associated with a decreased event-free survival (HR = 3.06 [1.14-8.22]; p = 0.027). Multivariate analysis adjusted for age and tumor stage confirmed this result (HR = 4.02 [1.36-11.90]; p = 0.012). Other investigated polymorphisms of the IGF1 gene were not significantly associated with event-free survival (all p values >0.05).

CONCLUSIONS

This study provides first evidence that IGF1 rs2946834 polymorphism is associated with clinical outcome of HER2-positive breast cancer patients. Further studies are warranted to validate these findings.

Common variants in IGF1 pathway genes and clinical outcomes after radical prostatectomy

BACKGROUND

Insulin-like growth factor-1 (IGF1) pathway plays a critical role in malignant transformation, and epidemiology studies have also shown that single nucleotide polymorphisms (SNPs) in IGF1 pathway genes are associated with prostate cancer risk. However, the clinical significance of these SNPs on prostate cancer aggressiveness and prognosis after radical prostatectomy (RP) has not been determined.

METHODS

We evaluated the associations of 4 common SNPs in IGF1 and IGF1R with age at diagnosis, preoperative prostate-specific antigen (PSA) level, pathologic Gleason score, pathologic stage, surgical margin, lymph node metastasis, and PSA recurrence in a cohort of 320 localized prostate cancer patients receiving RP. The prognostic significance on time to PSA recurrence was also assessed by Cox proportional hazards model.

RESULTS

IGF1 rs2946834 alleles/genotypes and an IGF1 specific haplotype AT, containing the minor allele of rs2946834, were associated (P ≤ 0.028) with a 1.49- to 2.22-fold higher risk of having advanced-stage prostate cancer. In addition, a genetic interaction profile consisting of IGF1 rs2946834 and IGF1R rs2016347 was significantly associated with PSA recurrence (P = 0.033).

CONCLUSIONS

Our study is the first to evaluate the impact of SNPs in IGF1 pathway genes on PSA recurrence. A genetic interaction between IGF1 rs2946834 and IGF1R rs2016347 might be a predictor of outcomes following RP.

BCAR1 expression improves prediction of biochemical reccurence after radical prostatectomy

BACKGROUND

Because prostate cancer exhibits a great variability in clinical outcome, biomarkers that can be used in daily practice are needed to better stratify patients into prognostic groups. Since steroid hormones play a central role in the development and progression of prostate cancer, we aimed to analyze in a matched nested case-control study the value of molecules involved in steroid signaling, to predict recurrence after radical prostatectomy, independently from standard prognostic tools.

METHODS

Among 1,200 patients treated by radical prostatectomy with negative margins with at least 4 years follow-up, 121 prostate cancers with biochemical relapse were matched after pathological reassessment with 121 cancers with identical clinicopathological features but without relapse. Immunohistochemistry was performed on tissue microarrays, using antibodies directed against molecules involved in androgen and estrogen signaling, including hormone receptors, enzymes (such as the five alpha reductases 1,2 and 3, aromatase, alpha-keto reductase 1C3 and squalene epoxidase), the breast cancer antiestrogen resistance 1 (BCAR1), and the proliferation marker Ki67.

RESULTS

The median follow-up for patients without recurrence was 7 years. Both cell proliferation and BCAR1 expression were significantly associated with biochemical relapse, in univariate and multivariate analysis. In subgroup analysis, the sole predictive marker in patients with well-differentiated prostate cancer was BCAR1 (P = 0.004), whereas only proliferation (P = 0.001) was significantly associated with relapse in less-differentiated prostate cancer patients.

CONCLUSIONS

BCAR1 is an independent predictor of recurrence after radical prostatectomy for "low risk" prostate cancer. The use of this biomarker may enable more individualized treatment approaches.

Association of androgen receptor, prostate-specific antigen, and CYP19 gene polymorphisms with prostate carcinoma and benign prostatic hyperplasia in a north Indian population

The genes involved in androgen pathway and metabolism have been reported to contribute considerably to prostate carcinoma (CaP) risk. The present study investigated the association of androgen receptor (AR), prostate-specific antigen (PSA or KLK3), and cytochrome P450 (CYP19) gene polymorphisms in CaP (n=105) and benign prostatic hyperplasia (BPH) (n=120) in comparison to normal healthy controls (n=106) in an Indian population. We also evaluated the functional consequences of these gene variants on AR and PSA mRNA expression. Significant association of short AR CAG repeats (≤24) with risk of CaP (odds ratios [OR]=2.98, p<0.001) and BPH (OR=1.96, p=0.01) was observed; however, CYP19 gene polymorphism was not found to be associated with disease phenotype (p>0.05). PSA G-158A SNP was found to be significantly associated with risk of CaP (AA: OR=2.68, p=0.016 and GA: OR=2.07, p=0.018) p-trend 0.031 and BPH (AA: OR=3.46, p<0.001 and GA: OR=2.47, p=0.03) p-trend 0.009, respectively. PSA G-158A genotype independently increased the risk of developing BPH (OR=16.37, p<0.001), irrespective of AR CAG repeat length. Using quantitative real-time polymerase chain reaction, we found a significant upregulation of AR and PSA mRNA expression in CaP comparison to BPH. While short AR CAG (≤24) repeats were associated with higher AR mRNA expression in CaP (p=0.002), the PSA SNP did not correlate with its mRNA expression. Interestingly, significantly higher risk estimates for CaP were observed for the combined analysis of short AR CAG and CYP19 genotypes (A2A2) (OR=7.18, p<0.001) or A2A3 (OR=7.60, p=0.004). Our results suggest significant association of androgen signaling gene polymorphisms with risk of CaP and BPH and provide evidence for a putative functional role of AR CAG repeat in regulating its mRNA expression and warrant the need of larger studies in the Indian population to confirm our results.

Insulin-like growth factor I (Igf-1) gene polymorphism in patients with non-metastatic breast cancer

We aimed to assess the association between IGF-I gene (CA repeats) polymorphism in breast cancer patients and their clinicopathological features, as well as disease recurrence and survival. Seventy-six non-metastatic breast cancer patients were enrolled in the present study. The IGF-I (CA) repeats were studied with polymerase chain reaction by using proper primers belonging to these gene areas from DNA samples. Results show that the non 19- non 19 homozygote were more common in patients without lymph node involvement (p=0.04), with low histological grade (p=0.04), with positive hormone receptor status (p=0.01), and in patients without recurrence (p=0.06). These results suggest that the non 19-non 19 carriers have some favorable prognostic factors, and IGF-I gene polymorphism (CA repeats) may affect disease recurrence and overall survival.

Clinical significance of insulin-like growth factor gene polymorphisms with survival in patients with gastrointestinal stromal tumors

Purpose

Insulin-like growth factors (IGFs) regulate a wide range of biological functions including cell proliferation, differentiation, and apoptosis through paracrine and autocrine mechanisms. Accordingly, the present study analyzed polymorphisms of IGF genes and their impact on the prognosis for patients with gastrointestinal stromal tumors (GISTs).

Methods

Two hundred-thirteen consecutive patients with GISTs who underwent curative surgery from 5 medical centers were enrolled in the present study. The genomic DNA was extracted from paraffin-embedded tumor tissue, and four IGF-1 (+2995C/A, +533C/T, IVS2-16540A/G, Ex4-177G/C) and one IGF-2 (IVS1+1280A/G) gene polymorphisms were determined using a Sequenom MassARRAY system.

Results

With a median follow-up of 18.4 months, the estimated 5-year relapse-free survival and overall survival rates were 69.9% and 86.7%, respectively. In a multivariate analysis including age, gender, primary site of disease, pathology, and risk stratification, no significant association was observed between the polymorphism of the IGF-1 and IGF-2 genes and survival.

Conclusion

None of the five IGF-1 and IGF-2 gene polymorphisms investigated in this study was found to be an independent prognostic marker for Korean patients with surgically resected GIST. However, further studies on a larger scale are warranted to clarify the role of IGF-1 and IGF-2 gene polymorphisms as a prognostic biomarker for GIST patients.

Polymorphisms of CYP19A1 and response to aromatase inhibitors in metastatic breast cancer patients

Single nucleotide polymorphisms (SNPs) in the gene encoding aromatase (CYP19A1) have been associated with differential benefit from letrozole treatment in metastatic breast cancer (mBC) patients, but validation is lacking. The aim was to investigate whether polymorphic variation of CYP19A1 and enzymes involved in estrogen and aromatase inhibitors (AIs) metabolism are associated with efficacy of AIs. 308 Women with estrogen-receptor-positive metastatic mBC treated with a third-generation AI were identified retrospectively. DNA was extracted from archival formalin-fixed paraffin embedded tumors and genotyped for 71 variants in 16 candidate genes, including CYP19A1. Time to treatment failure (TTF) was significantly improved in patients carrying the minor (T) allele of rs4775936 when compared to patients with the reference allele [HR = 0.79 per T allele (0.66-0.95); P = 0.012]. Patients with >7 TTTA repeats on either allele of CYP19A1 intron 4 had a lower risk of failure than those with a smaller repeat size [HR = 0.84 per >7 TTTA repeats (0.7-0.99); P = 0.04]. However, importantly in multivariate analysis, adjusting for the number of disease sites; disease-free interval from diagnosis to first recurrence, grade at diagnosis and first recurrence type neither variant maintained independent predictive significance. None of the 56 SNPs analyzed as an exploratory set showed significant association with TTF. Variants in CYP19A1 or other selected genes associated with AI metabolism were not independently associated with improved AI efficacy and emphasize the importance in pharmacogenetic studies of considering genetic biomarkers in the context of relevant prognostic factors.

Genetic polymorphism of IGF-I predicts recurrence in patients with gastric cancer who have undergone curative gastrectomy

BACKGROUND

To our knowledge, no reports have evaluated the effects of genetic polymorphisms of insulin-like growth factor-I (IGF-I) on clinical outcomes of gastric cancer patients.

METHODS

We retrospectively analyzed the impact of IGF-I polymorphisms on recurrence-free survival (RFS) in 430 patients with gastric cancer who underwent curative gastrectomy between 2001 and 2005 in our institution.

RESULTS

Among the 430 gastric cancer patients, 345 were pathological stage I or II, while 85 were stage III or IV. The median 5-year RFS rate was 85.3% (95% confidence interval [CI] 81.4-88.5). In a multivariate Cox model (adjusted for age, gender, histology, pathological stage, adjuvant chemotherapy, and history of diabetes), two IGF-I polymorphisms, rs1520220 and rs2195239, were significantly associated with RFS (hazard ratio [HR] 0.60, 95% CI 0.40-0.91; and HR 0.60, 95% CI 0.41-0.89, respectively, in a per-allele model). When stratified by stage (I-II versus III-IV), rs1520220 in particular was associated with RFS in patients with stage III-IV disease, with a P-value for interaction of 0.01.

CONCLUSIONS

Our findings indicate that genetic polymorphisms of IGF-I may have a substantial effect on recurrence for gastric cancer patients who have undergone curative gastrectomy. This information may help identify population subgroups that could benefit from IGF-I-targeting agents.

Outcome, clinical prognostic factors and genetic predictors of adverse reactions of intermittent combination chemotherapy with docetaxel, estramustine phosphate and carboplatin for castration-resistant prostate cancer

OBJECTIVES

Docetaxel-based chemotherapy is effective in patients with castration-resistant prostate cancer (CRPC). This phase II study assessed the outcome and predictive factors for prognosis and toxicity following intermittent chemotherapy with docetaxel, estramustine phosphate, and carboplatin (DEC) in patients with CRPC.

METHODS

Thirty-five patients were treated with a DEC regimen that consisted of a 28-day cycle of drugs as follows: docetaxel (60 mg/m(2) on day 1), carboplatin (AUC 5 on day 1) and estramustine phosphate (560 mg daily). Treatment was continued intermittently. The end point was to test the effect of DEC on the response rate and overall survival (OS). Statistical correlations between the outcomes and predictive factors, including clinical parameters and 8 single-nucleotide polymorphisms (SNPs) related to drug metabolism, were assessed.

RESULTS

Prostate-specific antigen levels decreased by more than 30% in 65.7% of the patients. The median OS following DEC was 17.8 months, and the median total time of chemotherapy holiday was 7.7 months (range 1.7-35.8). On multivariate analysis, serum lactate dehydrogenase (LDH) was an independent prognostic factor for OS (p = 0.007). On SNP analysis, patients carrying the TT genotype of the ABCB1 C3435T polymorphism showed a significantly more severe leukocytopenia during the first cycle of DEC therapy compared to patients with the CC + CT genotype (p = 0.036).

CONCLUSION

Combination chemotherapy with DEC has a potential effect on CRPC with acceptable toxicity. Serum LDH may be a promising predictor of prognosis, and the ABCB1 C3435T polymorphism may be a genetic predictor of the severity of leukocytopenia in patients with CRPC treated with DEC.

Association of rs6983561 polymorphism at 8q24 with prostate cancer mortality in a Japanese population

We conducted present study to address whether the rs6983561 polymorphism, an established genetic marker for prostate cancer susceptibility, was a prognostic indicator. We genotyped 518 Japanese patients with prostate cancer and analysed their survival retrospectively. As a result, patients with the CA/CC genotype of rs6983561 survived significantly longer than those with the AA genotype (P = .033).

BACKGROUND

Genome-wide association studies have revealed several genetic variants at 8q24 that are associated with prostate cancer susceptibility. Rs6983561 (A/C) is a single-nucleotide polymorphism located at 8q24 that has been established as a genetic risk marker for prostate cancer susceptibility. The present study investigated the association between the rs6983561 polymorphism and prostate cancer mortality in a Japanese population.

PATIENTS AND METHODS

The study examined 518 native Japanese male patients with sporadic prostate cancer. Germline DNA samples were obtained from all participants and genotyping of rs6983561 was performed using a TaqMan assay. Observation periods were from the date of diagnosis of prostate cancer to May 21, 2010. The Cox proportional hazards model was used to estimate the cause-specific survival (CSS) and the overall survival (OS).

RESULTS

Patients with the CA/CC genotype of rs6983561 survived significantly longer than those with the AA genotype. In a multivariate model, the hazard ratios (HRs) and 95% confidence intervals (CIs) of the CSS and the OS for the rs6983561 polymorphism were 2.438 (1.262 - 5.046, P = .007) and 1.957 (1.142 - 3.485, P = .014), respectively. When the analysis was restricted to subjects with metastatic disease, the HRs of the CSS and the OS were 3.353 (95% CI, 1.689 - 7.446; P = 3.76 x 10(-4)) and 3.361 (95% CI, 1.741 - 7.136; P = 1.70 x 10(-4)), respectively.

CONCLUSION

In the Japanese population examined in this study, the rs6983561 polymorphism at 8q24 was significantly associated with prostate cancer mortality, especially among patients with metastatic disease.

Polymorphic CA repeat length in insulin-like growth factor 1 and risk of breast cancer in Iranian women

To evaluate the association between breast cancer and cytosine-adenine (CA) dinucleotide repeat length polymorphisms in the promoter region of the Insulin-like Growth Factor 1 (IGF-1) gene, a case-control study of 215 breast cancer patients and 224 controls was conducted in Iranian women. The most common allele and genotype in both controls and patients were an allele length of 19 and a homozygous genotype of (CA)(19)/(CA)(19). Women with two alleles longer than 19 were found to be at a higher risk of breast cancer with an odds ratio of 4.1 (P = 0.0002). In contrast, women with two alleles shorter than 20 were at lower risk of breast cancer. These results suggest a novel association between CA repeat length in IGF-1 and risk of breast cancer.

Association of aromatase (TTTAn) repeat polymorphism length and the relationship between obesity and decreased sperm concentration

BACKGROUND

Obesity in men is associated with low sperm count, however, this finding is inconsistent. Here, we describe length of the short tandem repeat aromatase (CYP19A1) polymorphism and its relationship to increased weight and sperm count.

METHODS

A cohort of 215 men was recruited from the community and BMI, hormone levels and sperm parameters were determined at enrollment. Men (196) were genotyped for length of the tetranucleotide TTTA repeats polymorphism (TTTA(n)), defined as short (S ≤ 7 repeats) or long (L > 7 repeats). Genotypes were categorized using allele combinations as 'low repeats' = S-S, or 'high repeats' = S-L/L-L. Weight and sperm parameters were examined in relation to size of TTTA(n) repeat.

RESULTS

Mean (±SD) age was 29.8 ± 8.6 years and mean BMI was 25.6 ± 4.6 kg/m(2). Men with high repeats had higher estradiol (E(2)) levels (98.0 ± 33.36 pmol/l) than men with low repeats (85.9 ± 26.61 pmol/l; P= 0.026). Lower FSH levels tended to be present in men with high repeats versus men with low repeats (P= 0.052). After stratification by genotype, a negative correlation between BMI and sperm count (Pearson's coefficient = 0.406) was seen only among men with high repeats (P= 0.019). Only men with high repeats exhibited increased E(2) with increased weight. A decrease in testosterone: E(2) ratio with increasing BMI was more pronounced in men with high versus low, repeats (R(2) = 0.436 versus 0.281).

CONCLUSIONS

Higher TTTA repeat numbers (>7 repeats) in the aromatase gene are associated with a negative relationship between obesity and sperm count. The effect of obesity on E(2) and sperm count appears to be absent in men with low (≤7) repeats.

New quantification method for estradiol in the prostatic tissues of benign prostatic hyperplasia using liquid chromatography-tandem mass spectrometry

Estrogen is suspected to play a role in the pathogenesis of benign prostatic hyperplasia (BPH) and prostate cancer. To clarify the role of estradiol (E2) in the prostatic tissues (prostatic tissue E2) during the development of prostatic disorders, we developed a new sensitive and specific quantification method for prostatic tissue E2 using liquid chromatography-tandem mass spectrometry (LC-MS/MS). For the solid-phase extraction, E2 was purified by anion-exchange through an Oasis MAX cartridge. In addition, after the formation of 3-pentaflurobenzyl-17beta-pyridinium-estradiol derivative (E2-PFBPY), E2-PFBPY was purified by cation-exchange through an Oasis WCX cartridge. These processes in the LC-MS/MS method improved the specificity and sensitivity for prostatic tissue E2 measurement, compared to the radioimmunoassay (RIA) method. The validation tests showed that intra-day and inter-day precisions were both within +/-15% (except for 15.5% of the inter-day precision of the lowest concentration), with the accuracy ranging from 88 to 110%. The quantification limit of this assay was 0.15pg/tube in our method, which was 80-fold more sensitive than that of the RIA method. With the use of our present method, the median E2 levels in the prostatic tissues in patients with BPH (n=20, median age: 71 years) were 12.0pg/g tissue (95% confidence interval=9.1-22.6pg/g tissue). Furthermore, the E2 levels increased significantly with aging. These results showed that our present method would be useful for elucidating the role of prostatic tissue E2 in the development of prostatic disorders with a small amount of tissue samples.

An aromatase polymorphism modulates the relationship between weight and estradiol levels in obese men

OBJECTIVE

To describe the influence of the TTTA aromatase polymorphism (TTTAn) on the relation between obesity and plasma estradiol (E(2)) in obese men.

DESIGN

A 2-year cohort study.

SETTING

Clinical research center.

PATIENT(S)

Severely obese men (31 who had had gastric bypass surgery and 118 controls).

INTERVENTION(S)

Men were genotyped for the TTTAn CYP19A1 polymorphism. Anthropomorphic measures, plasma E(2), and other hormonal levels were determined at baseline and 2-year follow-up.

MAIN OUTCOMES MEASURE(S)

Relationships between weight and changes in weight and plasma E(2) were examined in relation to the TTTAn polymorphism.

RESULT(S)

The mean age was 46.5 ± 10.82 years, and mean body mass index was 47.1 ± 8.46 kg/m(2). The most common repeats were 7 and 11. TTTAn number did not correlate with plasma E(2) in the univariate analysis. When patients were stratified per weight group, the correlation between plasma E(2) and weight was seen only among men with a higher TTTA repeat at baseline and 2 years. Similarly, only men with higher TTTA exhibited reduced E(2) levels after weight loss.

CONCLUSION(S)

A higher TTTA repeat is associated with a strengthened relationship between obesity and E(2). The well-established effect of increased weight on plasma E(2) appears to be absent in men with low TTTA numbers.

The novel tumor-suppressor Mel-18 in prostate cancer: its functional polymorphism, expression and clinical significance

Mel-18 is a member of the polycomb group (PcG) proteins, which are chromatin regulatory factors and play important roles in development and oncogenesis. This study was designed to investigate the clinical and prognostic significance of Mel-18 in patients with prostate cancer. A total of 539 native Japanese subjects consisting of 393 prostate cancer patients and 146 controls were enrolled in this study. Mel-18 genotyping was analyzed using a PCR-RFLP method and an automated sequencer using the GENESCAN software. Immunohistochemistry revealed that Mel-18 expression was diminished in high grade and high stage prostate cancers. Moreover, patients with positive Mel-18 expression had significantly longer PSA recurrence-free survival than patients negative for Mel-18 expression (p=0.038). A Mel-18 1805A/G SNP was located in the 3' untranslated region and was predicted to alter the secondary structure of the mRNA. Mel-18 mRNA expression of the 1805A allele was clearly higher than expression of the 1805G allele by allele specific quantitative RT-PCR. In multivariate analysis, a homozygous G allele genotype and negative Mel-18 expression were independent risk factors predicting high PSA recurrence after radical prostatectomy, with HRs of 2.757 (p=0.022) and 2.271 (p=0.045), respectively. Moreover, the G allele was also an independent predictor of poor cancer-specific survival with an HR of 4.658 (p=0.019) for patients with stage D2 prostate cancer. This is the first study to provide important evidence demonstrating that Mel-18 is a tumor suppressor and possible therapeutic target, as well as a diagnostic marker for poor prognosis in prostate cancer patients.

Polymorphisms of pro-inflammatory genes and prostate cancer risk: a pharmacogenomic approach

In this paper, we consider the role of the genetics of inflammation in the pathophysiology of prostate cancer (PCa). This paper is not an extensive review of the literature, rather it is an expert opinion based on data from authors' laboratories on age-related diseases and inflammation. The aim is the detection of a risk profile that potentially allows both the early identification of individuals at risk for disease and the possible discovery of potential targets for medication. In fact, a major goal of clinical research is to improve early detection of age-related diseases, cancer included, by developing tools to move diagnosis backward in disease temporal course, i.e., before the clinical manifestation of the malady, where treatment might play a decisive role in preventing or significantly retarding the manifestation of the disease. The better understanding of the function and the regulation of inflammatory pathway in PCa may help to know the mechanisms of its formation and progression, as well as to identify new targets for the refinement of new treatment such as the pharmacogenomics approach.

Association of genetic polymorphisms at 8q24 with the risk of prostate cancer in a Japanese population

BACKGROUND

Genetic factors, as well as a combination of environmental factors, contribute to the risk of prostate cancer (PC). Recently, genome-wide linkage studies found several independent single nucleotide polymorphisms (SNPs) that are strongly associated with PC on chromosome 8q24.

METHODS

We analyzed two of these SNPs, rs1447295 and rs6983267, to examine association with the risk of PC in Japanese men. These SNPs were examined by a mismatch PCR-RFLP method in 507 PC patients (286 aggressive and 221 non-aggressive) and in 511 non-PC patients (124 benign prostatic hyperplasia and 387 normal male controls) and the allele frequencies were then compared between groups.

RESULTS

The rs1447295 A allele was associated with susceptibility to PC (PC vs. non-PC: P = 0.041; OR, 1.28; 95%CI = 1.01-1.61), and was more significantly associated with disease in aggressive PC (aggressive PC vs. normal controls, P = 0.013; OR, 1.43; 95%CI = 1.08-1.90). The rs6983267 G allele did not show significant association with susceptibility to PC (PC vs. non-PC: P = 0.967; OR, 1.00; 95%CI = 0.83-1.21). However, it was associated with disease in non-aggressive PC (non-aggressive PC vs. normal controls: P = 0.0068; OR, 1.43; 95%CI = 1.10-1.85).

CONCLUSIONS

The two SNPs at 8q24 were associated with an increased risk of prostate cancer and contributed to tumor aggression in Japanese men.

Current topics and perspectives relating to hormone therapy for prostate cancer

Prostate cancer is androgen-dependent, and hormone therapy, mainly achieved by androgen deprivation, has been one of the main treatment modalities in the clinical management of prostate cancer patients for more than six decades. In the 1980s, luteinizing hormone-releasing hormone agonists, which reduce testosterone to castration levels, were introduced Also, after the 1980s, nonsteroidal antiandrogens were developed in addition to steroidal antiandrogens. Since then, so-called maximum androgen blockade (MAB)/combined androgen blockade (CAB), which is a combination of surgical or medical castration and oral antiandrogens, has been developed. More recently, novel treatment modalities have been developed, such as intermittent androgen suppression, nonsteroidal antiandrogen monotherapy, and alternative antiandrogen therapy after relapse from initial MAB/CAB, The present article focuses on these treatment modalities to review current topics and perspectives with respect to hormone therapy for prostate cancer.

Polymorphisms of fibroblast growth factor receptor 4 have association with the development of prostate cancer and benign prostatic hyperplasia and the progression of prostate cancer in a Japanese population

Fibroblast growth factor receptor 4 (FGFR4) is a member of a family of transmembrane receptors with ligand-induced tyrosine kinase activity. The Glycine (Gly) to Arginine (Arg) polymorphism at codon 388 (Gly388Arg), which encodes an amino acid in the transmembrane part of the FGFR4 gene, was reported to be associated with an increased risk in some carcinomas. We investigated the association between the Gly388Arg polymorphism or the G or A polymorphism at intron 11 (rs2011077) of FGFR4, which was located 1,213 base pairs apart from the Gly388Arg polymorphism, and the risk of prostate cancer or benign prostate hyperplasia (BPH), and the prostate cancer disease status in Japanese men. Genotypes of Gly388Arg and rs2011077 polymorphisms of FGFR4 were determined in 492 patients with prostate cancer, 165 patients with BPH and 179 male controls. Regarding the Gly388Arg polymorphism, individuals with the ArgArg genotype had a 2.207- and 1.958-fold increased risk of prostate cancer and BPH, and a 1.804-fold increased risk of metastatic prostate cancer compared with those with the GlyGly genotype. Regarding the rs2011077 polymorphism, individuals with the GG genotype had a 6.260- and 3.033-fold increased risk of prostate cancer and BPH, and a 5.550-fold increased risk of metastatic prostate cancer compared with those with the AA genotype. Our results indicate that the FGFR4 Arg allele of the Gly388Arg polymorphism and the G allele of the rs2011077 polymorphism have a significant impact on the development of prostate cancer and BPH, and the progression of prostate cancer in a Japanese population.

[Chemotherapy for prostate cancer]

For many years the benefit of chemotherapy in patients with prostate cancer was thought to be limited to palliation of late-stage disease, and thus this treatment option only became involved in patient care towards the end of the disease process, if at all. However, two landmark phase-III trials with docetaxel-based therapy (TAX 327 and Southwest Oncology Group, SWOG, 9916) have shown a survival benefit for patients with hormone refractory prostate cancer (HRPC) thus prompting a change in patterns of care. With raising interest for chemotherapeutic options and clinical trials for new drugs and new indications (neoadjuvant therapy, adjuvant therapy, increasing PSA levels after local treatment, and hormone sensitive cancer) under way our goal was to review within the context of a multidisciplinary team the available evidence and explore the standard for the medical treatment of prostate cancer outside of clinical trials. We are carefully evaluating the current treatment recommendations based on the available evidence and highlight potential future treatment options but also discuss important clinical topics (treatment until progression versus the advantage of chemo holidays, definition of particular patient subgroups and potential second line options) for which there are no clear cut answers to date. The role and importance of radiotherapy, biphosphonate treatment and the medical management of pain and side effects is also discussed. The multitude of treatment options for patients with advanced prostate cancer clearly asks for a close collaboration between urologists, medical oncologists and radiation therapists.

A genetic polymorphism of the osteoprotegerin gene is associated with an increased risk of advanced prostate cancer

Background

The purpose of this study was to evaluate the role of osteoprotegerin gene (OPG) polymorphisms as genetic modifiers in the etiology of prostate cancer (PCa) and disease progression.

Methods

Three hundred and sixty one patients with PCa and 195 normal controls were enrolled in the study, and two genetic polymorphisms, 149 T/C and 950 T/C in the putative promoter region of OPG, were genotyped.

Results

There was no significant difference in the genotype frequencies between PCa patients and controls (P = 0.939 and 0.294 for 149 T/C and 950 T/C polymorphisms, respectively). However, those patients with TC and TT genotypes in the 950 T/C polymorphism had a significantly increased risk of extraprostatic (age-adjusted odds ratio; aOR = 1.74 and 2.03 for TC and TT genotypes compared with the CC genotype, P = 0.028) and metastatic disease (aOR = 1.72 and 2.76 for TC and TT genotypes compared with the CC genotype, P = 0.009) compared with those with the CC genotype. In addition, analysis of the metastatic PCa patients (Stage D) showed that the presence of the T allele of the OPG 950 T/C polymorphism was an independent risk factor predicting survival by Cox proportional hazard regression analyses (P = 0.031).

Conclusion

Progression of PCa may be influenced by an intrinsic genetic factor of the host's bone metabolism. The variant C allele of 950 T/C in the OPG promoter may play a major role as a genetic safe guard against progression in patients with PCa.

The CYP19 TTTA repeat polymorphism is related to the prognosis of premenopausal stage I-II and operable stage III breast cancers

PURPOSE

Given the critical role of the CYP19 gene, encoding aromatase, in estrogen synthesis and the association of the estrogen level with its TTTA repeat polymorphism, the potential influence of this polymorphism on breast cancer survival, and hence management, deserves further study.

METHODS

Genotyping for the CYP19 TTTA repeat polymorphism was performed on 482 stage I-II and operable stage III Taiwanese breast cancer patients. Patients with more than seven TTTA repeats in either allele of CYP19 were defined as having the long allele. We correlated clinical variables and CYP19 genotypic polymorphism with outcome.

RESULTS

In hormone receptor (HR)-positive breast cancers, premenopausal patients with the long allele of the CYP19 polymorphism had a significantly higher overall survival (OS) rate (8-year, 89% versus 68%; p= .003) than those without it. This difference was further demonstrated by a multivariate analysis (OS hazard ratio, 1.53; p= .041). In postmenopausal women or patients with HR-negative breast cancer, there was no significant difference in OS between patients with or without the long allele. In premenopausal women with HR-positive cancers, adequate intensity adjuvant chemotherapy did not achieve a greater OS rate than suboptimal chemotherapy in patients with the long allele, but it resulted in a significantly higher OS rate (p= .011) than suboptimal chemotherapy in women without the long allele.

CONCLUSIONS

The CYP19 TTTA repeat polymorphism is associated with survival in premenopausal women, but not in postmenopausal women, with HR-positive breast cancers. Premenopausal women with the long allele have a greater survival rate and may not gain benefit from adjuvant chemotherapy.

Effect of SLCO1B3 haplotype on testosterone transport and clinical outcome in caucasian patients with androgen-independent prostatic cancer

PURPOSE

The organic anion transporter OATP1B3, encoded by SLCO1B3, is involved in the transport of steroid hormones. However, its role in testosterone uptake and clinical outcome of prostatic cancer is unknown. This study examined (a) the SLCO1B3 genotype in cancer cells as well as the uptake of testosterone by cells transfected with genetic variants of SLCO1B3; (b) the expression of OATP1B3 in normal prostate, benign prostatic hyperplasia, and prostatic cancer; and (c) the role of SLCO1B3 haplotype on clinical outcome of Caucasian patients with androgen-independent prostatic cancer.

EXPERIMENTAL DESIGN

SLCO1B3 genotype was assessed in the NCI-60 panel of tumor cells by sequencing, whereas testosterone transport was analyzed in Cos-7 cells transfected with WT, 334G, and 699A SLCO1B3 variants. OATP1B3 expression in prostatic tissues was examined by fluorescence microscopy, and the relationship between SLCO1B3 haplotypes and survival was examined in patients.

RESULTS

Cells transfected with wild-type (334T/699G) SLCO1B3, or with a vector containing either the 334G or 699A variants, actively transported testosterone, whereas its uptake was impaired in cells transfected with a gene carrying both 334G and 699A single nucleotide polymorphisms. Prostatic cancer overexpresses OATP1B3 compared with normal or benign hyperplastic tissue; patients with SLCO1B3 334GG/699AA haplotype showed longer median survival (8.5 versus 6.4 years; P = 0.020) and improved survival probability at 10 years (42% versus 23%; P < 0.023) than patients carrying TT/AA and TG/GA haplotypes.

CONCLUSIONS

The common SLCO1B3 GG/AA haplotype is associated with impaired testosterone transport and improved survival in patients with prostatic cancer.

The emerging role of the insulin-like growth factor pathway as a therapeutic target in cancer

The insulin-like growth factor signaling pathway is important in many human cancers based on data from experimental models as well as epidemiological studies. Important therapies targeted at this pathway have been or are being developed, including monoclonal antibodies to the insulin-like growth factor-I receptor and small molecule inhibitors of the tyrosine kinase function of this receptor. These investigational therapies are now being studied in clinical trials. Emerging data from phase I trials are encouraging regarding the safety of the monoclonal antibodies. In this manuscript, the rationale for targeting the insulin-like growth factor system is reviewed in addition to a summary of the available clinical trial data.

Molecular mechanisms and treatment of bone metastasis

The metastasis of cancer cells to bone alters bone architecture and mineral homeostasis. As described by the 'seed and soil' hypothesis, bone represents a fertile ground for cancer cells to flourish. A 'vicious cycle' of reciprocal bone-cancer cellular signals occurs with osteolytic (bone-resorbing) metastases, and a similar mechanism likely modulates osteoblastic (bone-forming) metastatic lesions as well. The development of targeted therapies either to block initial cancer cell chemotaxis, invasion and adhesion or to break the 'vicious cycle' is dependent on a more complete understanding of bone metastases. Although bisphosphonates delay progression of skeletal metastases, it is clear that more-effective therapies are needed. Cancer-associated bone morbidity remains a major public health problem, and to improve therapy and prevention it is important to understand the pathophysiology of the effects of cancer on bone. This review details scientific advances in this area.

Inherited variation in the androgen pathway is associated with the efficacy of androgen-deprivation therapy in men with prostate cancer

PURPOSE

Androgen-deprivation therapy (ADT) is the most common and effective systemic therapy for advanced prostate cancer. We hypothesized that germline genetic variation in the androgen axis would improve the efficacy of ADT.

PATIENTS AND METHODS

A cohort of 529 men with advanced prostate cancer treated with ADT was genotyped for 129 DNA polymorphisms distributed across 20 genes involved in androgen metabolism.

RESULTS

Three polymorphisms in separate genes (CYP19A1, HSD3B1, and HSD17B4) were significantly (P < .01) associated with time to progression (TTP) during ADT, remaining so in multivariate analyses and after correcting for the number of hypotheses tested. Individuals carrying more than one of the polymorphisms associated with improved TTP demonstrated a better response to therapy than individuals carrying zero or one (P < .0001).

CONCLUSION

This report is the first to examine the influence of inherited variation in the androgen metabolic pathway on the efficacy of ADT, establishing the importance of pharmacogenomics on individual's response to this therapy. At least two potential clinical benefits may be realized from this study. The first is prognostic -genotyping patients at these loci may yield important information that could improve efficacy prediction. The second is therapeutic -these results shed light on the pathways that govern response to ADT. Drugs could be developed (or may already exist) to inhibit or augment these targets to improve ADT efficacy.