Natural compound So-2 suppresses triple-negative breast cancer through inducing ferroptosis via downregulating transcription factor E2F7

Triple-negative breast cancer (TNBC), accounting for about 15∼18% of all breast cancers, is notorious for its poor prognosis, high rate of relapse and short overall survival. Because of lacking effective therapeutic targets or drugs, treatment of TNBC in clinical encounters great obstacle. Siegesbeckiaorientalis L. have been used as a traditional Chinese medicine "Xi-Xian-Cao" for centuries with multiple medicinal benefits including cancerous treatment. We have reported the isolation of twenty-seven germacranolides including So-2 from the aerial parts of S. orientalis with potent cytotoxicity against breast cancer cells. The studyaims to verified the anti-TNBC function of the natural compound So-2 both in vitro and vivo and uncover the underlying mechanism. The results showed that So-2 caused cell cycle arrest and suppress TNBC cell proliferation and migration. Also, So-2 was first identified to be a bona fide ferroptosis inducer in TNBC cells. So-2 effectively suppressed tumor growth of TNBC by using an orthotopic transplantation tumor model. We also characterized the oncogenic role of the transcription factor E2F7 in TNBC. E2F7 was demonstrated to be involved in the ferroptosis-inducing and tumor suppression effect of So-2. Altogether, So-2 exhibits inhibitory effect on TNBC both in vitro and vivo by inducing TNBC ferroptosis via downregulating the expression of E2F7. These findings provide valuable insight into the pathogenesis of TNBC. The natural compound So-2, isolated from Chinese traditional medicine, might be a prospective drug candidate in TNBC therapy.

P5-13-13: The Role of Topoisomerase IIa in Predicting Sensitivity to Anthracyclines in Breast Cancer Patients: A Meta-Analysis of Published Literatures

Topoisomerase IIα is not only a proliferation marker of tumor cells but also a target for anthracycline-based chemotherapy. Both in vitro and in vivo studies have shown that there was a relationship between topo IIα and chemosensitivity to anthracyclines, but the predictive role of topo IIα is still controversial in breast cancer patients. A meta-analysis based on published studies was performed with the aim of obtaining an accurate evaluation of the association between topo IIα and sensitivity to anthracycline-based chemotherapy. A total of 13 eligible studies including 2,633 cases and 2,118 controls were identified. Topo IIα was associated with sensitivity to anthracyclines in locally advanced breast cancer patients who received neoadjuvant chemotherapy (RR = 1.93, 95%CI: 1.27−2.94, P=0.002; RR =1.98, 95%CI: 1.37−2.86, P<0.001). In early breast cancer patients who received anthracycline-based adjuvant chemotherapy compared with non-taxane-based polychemotherapy, amplification(HR = 0.64, 95%CI: 0.49−0.83, P=0.001; HR = 0.59, 95% CI: 0.35−1.01, P=0.056) or deletion (HR = 0.82, 95%CI: 0.67−1.00, P=0.051; HR =0.58, 95%CI: 0.35−0.97, P=0.036) of topo IIα was significantly associated with better RFS and OS. The subgroup analysis in the early breast cancer patients indicated that taxane could be an interference for evaluation of the predictive role of topo IIα. In summary, the present meta-analysis suggests that topo IIα is a predictive factor for breast cancer patients who received anthracycline-based chemotherapy. Larger and well-designed prospective studies are required to further evaluate the predictive role of topo IIα in clinical practice.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P5-13-13.

Diffusion-Weighted MRI in Predicting the Efficacy of Neoadjuvant Chemotherapy of Breast Cancer

Objective: To approach the apparent diffusion coefficient(ADC) obtained on diffusion weighted imaging (DWI) in predicting the response of breast cancer to neoadjuvant chemotherapy.Methods: 53 locally advanced breast cancer patients participated in this prospective study on neoadjuvant chemotherapy. All patients were treated with weekly neoadjuvant paclitaxel plus carboplatin for 4 cycles. DWI and ADC value were examined before chemotherapy(the first time point), after the first and the forth cycle of chemotherapy(the second and the third time point). Patients were categorized as high responders if their ADC at the second time point were higher by 2 times the standard deviation than the mean pre-chemotherapy ADC, and otherwise the patients were considered as low responders. Logistic regression was conducted to examine the independent factors predictive of clinical complete response(CR) and pathologic complete response(pCR).Results: CR was documented in 13 patients (24.5%); partial response in 36 patients (67.9%); stable disease in 4 patients (7.5%) and no patient had progressive disease. 11 patients(20.8%) have achieved pCR. There was a strong positive correlation between the percentage changes in ADC value at the third time points and the degree of the tumor reduction. A significant increase in ADC value was observed at the second time point compared with the first time point (1.104±0.117×10-3mm2/s, 1.220±0.158×10-3mm2/s, P<0.001), while the decrease of the longest diameter of the tumors measured by physical examination, ultrasound or MRI or the tumor volumn measured by MRI were not (P>0.05). Logistic regression revealed that percentage changes of ADC value at the second time point were significantly associated with CR(P=0.022, hazard ratio[HR] =1.08, 95% confidence interval[CI]: 1.01∼1.16) and pCR(P=0.022, HR =1.11, 95%CI: 1.02∼1.21). The AUC value of the receiver operating characteristic curve were 0.721(95%CI: 0.512∼0.931, P=0.017) and 0.775(95%CI: 0.598∼0.952, P=0.005) in the two diagnostic tests for CR and pCR, and the sensitivity and specificity were 76.9%, 63.6% and 77.5%, 90.5%, respectively. According to categorizing system described above, 10 patients(18.9%) were considered as high responders and 43 patients(81.1%) low responders. 7 patients(70%) of the high responders have achieved clinical CR and pCR while for the low responders there were only 6 patients(14.0%) and 4 patients (9.3%) proven to have CR and pCR. The difference have both reached statistical significance(P=0.001, P<0.001). Logistic regression confirmed that the categorizing system was independently predictive of CR(P=0.006, HR=42.26, 95%CI: 2.86∼624.08) and pCR(P=0.013, HR=25.19, 95%CI: 2.00∼318.91). Taking this categorizing system as a dignostic test, the sensitivity and specificity were 53.8% and 92.5% for CR and 63.6% and 92.9% for pCR, respectively.Conclusions: The change of ADC value obtained on DWI after the first cycle of neoadjuvant chemotherapy occured prior to the morphologic changes of the tumor and at this time ADC value could to some extent predict the efficacy of neoadjuvant chemotherapy.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 4025.

Estrogen Receptor Expression: Possible Predictor of Pathological Complete Response to Neoadjuvant Chemotherapy in Locally Advanced Breast Cancer Patients

BackgroundEstrogen receptor(ER) status has been found to correlate inversely to pathologic complete response (pCR) rates of neoadjuvant chemotherapy(NAC) of breast cancer. However, not all ER-positive breast cancer respond equally to NAC. The present study aimed to determine the relationship between different ER expression level with pCR in locally advanced breast cancer(LABC) patients who have received NAC.MethodsA retrospective study of 332 female unilateral LABC patients undergoing NAC was performed. All patients were confirmed as invasive breast cancer before treated with NAC, including VE (vinorelbine, epirubicin), CEF (cyclophosphamide, epirubicin, fluorouracil) and PCb regimen (paclitaxel, carboplatin). All patients underwent radical surgery and pCR was defined as the absence of invasive breast cancer in both breast and axillary lymph nodes. ER status were checked using the established immunohistochemical(IHC) method and defined as negative, weakly positive(1+), medium positive(2+) and strongly positive(3+). Binary logistic regression was performed to determine the independent predictors of pCR.ResultsER negativity, 1+, 2+ and 3+ were found in 156, 108, 37 and 31 patients, of which 42(26.9%), 21(19.4%), 3(8.1%) and 1 patients(3.2%) have achieved pCR. Binary logistic regression showed that different ER expression level(P=0.021) and HER2 status(P=0.007, hazard ratio[HR] =2.557, 95% confidence interval[CI]: 1.297∼5.038) were significantly associated with the pCR rates. pCR was much more likely to occur in patients with ER-negative(P=0.024, HR =13.119, 95% CI: 1.402∼122.774) or ER 1+(P=0.025, HR=12.928, 95% CI: 1.388∼120.390) tumors than those with ER 3+ tumors.ConclusionER weekly positive patients also gain considerable benefit from NAC, which is probably less effective in ER strongly positive patients in terms of pCR.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 1104.

Genetic Contribution of GADD45A to Susceptibility to Sporadic and Non-BRCA1/2 Familial Breast Cancers: A Systemic Evaluation in Chinese Populations

GADD45A is a candidate breast cancer susceptibility gene because its product participates in DNA repair and it is a downstream gene of p53 and BRCA1, both of which are breast cancer susceptibility genes. The genetic contribution of GADD45A to sporadic and familial breast cancer is still ambiguous. We screened germline mutation of GADD45A in 185 non-BRCA1/2 familial breast cancer patients, but no deleterious mutation was found. Seven single-nucleotide-polymorphisms were identified in a sub-sample. Five common variants (minor allele frequency (MAF)>10%) were genotyped for association analyses to scrutinize the relationship between breast cancer and polymorphisms in GADD45A in two independent population sets. In the first case-control study, a comparison of genotype frequencies between sporadic breast cancer patients and controls indicated the CT/TT-genotypes of +1506C>T and CG/CC-genotypes of +3204G>C were associated with decreased breast cancer risk (adjusted odds ratio (OR), 0.77; 95% confidence interval (CI), 0.62-0.96; and adjusted OR, 0.71; 95%CI, 0.57-0.88, respectively) compared with their wild-type homozygotes. A common hyplotype CGTCC was also associated with reduced risk (P=1.0×10-4). In a second familial breast cancer patient-based case-control study, although +1506C>T and +3204G>C failed to be validated, the haplotype CGTCC showed a borderline significance. Notably, the combined P-values were robust for +3204G>C (P=3.1×10-4) and CGTCC (P=1.6×10-5). Moreover, CGTCC was correlated with a higher GADD45A expression in normal breast tissues. In conclusion, although germline mutation of GADD45A is not common in familial breast cancer patients, polymorphisms/haplotypes in GADD45A contribute to breast cancer risk, at least to sporadic breast cancer.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 5163.

Intermittent Hypoxia: Potential Factor of Resistance to Endocrine Therapy

Background: It has been reported that intermittent hypoxia, which is likely more prevalent than acute hypoxia in breast cancers, can cause persistent depression of estrogen receptor alpha (ER-α) expression in breast cell lines. However, it remains suspension whether intermittent hypoxia may be associated with resistance to endocrine therapy.Material and methods: The role of intermittent hypoxia in resistance to endocrine therapy was investigated in ER-α positive breast cell lines and animal models.Results: We observed that intermittent hypoxia promoted cancer cell proliferation in vitro and in vivo compared with normoxia. At both mRNA and protein levels, intermittent hypoxia induced down-regulation of ER-α and factor inhibiting HIF-1 (FIH) as well as up-regulation of hypoxia inducible factor-1 alpha (HIF-1α) and carbonic anhydrase IX (CA-IX). ER-α positive breast cancer cells under normoxic condition were capable of an intact response to ICI 182,780 (Tocris), whereas the inhibitory effect of ICI 182,780 (Tocris) was significantly reduced in those after intermittent hypoxia. Such effect was further validated with fulvestrant (Astrazeneca) in the animal models. To clarify whether intermittent hypoxia was associated with resistance to endocrine therapy, the expression of HIF-1α, a critical regulator of hypoxia-related pathway, was blocked by a reformed type of small interfering RNA (siRNA), stealth RNAi (Invitrogen), which can reduce the cytotoxic interferon response unlike conventional siRNA. Interestingly, knock-down of HIF-1α did result in the restoration of not only the ER-α expression but also the response to endocrine therapy, which was reproducible with administration of Bortezomib, a proteasome inhibitor of HIF-1α.Discussion: These data provide functional evidence that intermittent hypoxia may confer resistance to endocrine therapy in breast cancers through the crosstalk between HIF-1α and ER-α signaling, which holds a promise to overcome endocrine resistance.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 5148.

Epidemiology of Triple Negative Breast Cancer in China

Background:The classification of tumors based on the gene expression may define intrinsic breast cancer subtypes in which the effect of risk factors could be more obvious. We sought to assess the risk factors for triple negative breast cancer on Chinese population.Methods: A retrospective study of 5761 patients was carried out from a large database of breast cancer patients undergoing surgery between January 1, 1991 and June 31, 2008 in Cancer Hospital, Fudan University, Shanghai, China. Univariate analyses were performed by chi-square test of Student's t test and multivariate analyses by logistic regression.Results: A total of 1108 women were identified as having triple negative breast cancer and were compared with the 4653 women with non-triple negative. Regardless the pathological discrepancy, women with triple negative breast cancers were significantly more likely to be younger age(P=0.001; OR=1.615, 95%CI=1.207-2.160), premenopausal (P = 0.003; OR = 1.570, 95% CI = 1.171-2.106) and parous women (P = 0.001; OR = 1.741, 95% CI = 1.269-2.387).There seems no associations with increasing risk of triple negative breast cancer for breastfeeding (P=0.126), younger age at menarche (P=0.129), first degree family history (P=0.111) and oral contraceptive usage (P=0.251).Conclusion:Based on this large population study in Chinese breast cancer patients, the risk factors for triple negative phenotype may be somewhat different from those for Western women. Therefore, a better knowledge of this issue is warranted due to it may have impact on clinical outcomes and may offer some insight into the process of carcinogenesis and therapeutic efficacy.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 2065.

Postsurgical drainage and the risk of breast cancer recurrence in Chinese breast cancer patients

e22234

Background: Clinical investigations suggest that while primary breast cancer surgical removal favorably modifiers the natural history of breast cancer. Postoperative drainage, a surgery-derived discharge after breast cancer surgery, reflecting some biological features of surgical stimulation, was assessed and explored its relationship with breast cancer recurrence in this study. Methods: A total of 1445 women undergoing surgery between Jan 1, 2000 and Dec31, 2002 in Cancer Hospital of Fudan University, Shanghai, China was retrospectively studied. Survival curves were performed with Kaplan-Meier method and the predictive value of postsurgical drainage was estimated using proportional Cox regression model. Conclusions: The larger drainage volume POD 1 is a useful marker, suggesting a greater stimulation to surgical treatment compared to the lower ones. Awareness of the relationship between early surgery-stimulated effects and harmful wound healing response might help to explore new strategies to block or deplete these harmful effects, resulting in improving patients' survival.

No significant financial relationships to disclose.

Demographic features and prognostic profiles of breast cancer patients presenting with nipple discharge in Chinese population

e22204

Background: Breast cancer patients with nipple discharge (ND) may constitute a distinct clinical entity compared to those without ND, which has not been well elucidated in previous reports. We sought to analyze the demographic features and prognostic profiles of breast cancer patients presenting with nipple discharge in Chinese population. Methods: A total of 3234 patients, categorized as ND (2.47%) and non-nipple discharge (NND; 97.53%) according to different initial signs, were retrospectively analyzed. Survival curves were performed with Kaplan-Meier method and annual recurrence hazard was estimated by hazard function. Results: ND group tended to have smaller tumors and less axillary lymph node (ALN) involvement than NND group (P < 0.05). In the univariate analysis, we found significantly different recurrence-free survivals (RFS) between subgroups (P = 0.0182), with the rate of 77.78% for ND group and 72.46% for the other at the 11th year respectively. In Cox proportional hazards regression analysis, we found that tumor size (P < 0.001), ALN status (P < 0.001) were independent prognostic factors for RFS. To further evaluate whether prognostic effect of ND status remained unabated over time, the test for lack of proportionality was performed. However, it was statistically significant (global test, P = 0.039), which hinted at a demand for the employment of Cox non-proportional hazards regression in this analysis. In time dependent Cox model, ND status (P = 0.0495) as well as ERBB2 status (P = 0.017), tumor size (P < 0.001), ALN status (P < 0.001) were independent prognostic factors when ND and ERBB2 status were taken as time-varying covariates. Annual hazard rates for recurrence remained lower on ND group until approximately 4.5 years after surgery, while the situation was just the opposite thereafter. Conclusions: Our findings suggested that demographic features and prognostic profiles were quite different between breast cancers presenting with and without ND in Chinese population, which may indirectly uncover distinct biological behaviors and potentially enlighten novel therapeutic approaches for patients with different initial signs.

No significant financial relationships to disclose.

Luminal group may give more benefit for invasive micropapillary carcinoma component breast cancer patients: experience from Cancer Hospital Fudan University

Abstract #6152

Objective: Comparative studies on clinical features and outcomes of very rare invasive micropapillary carcinoma of breast cancer of 4 subtypes by immunohistochemistry staining.&#x2028; Methods: From Aug 2005 to Mar 2008, a total of 52 breast cancer patients(BCPs) with an invasive micropapillary component (IMPC) among 1951 Chinese BCPs with complete of clinicopathologic data in our institution were enrolled into a retrospective analysis. We characterized all these 52 patients and analyzed using various parameters.&#x2028; Results: The 52 cases of breast carcinoma with an IMPC all occurred in women. Mean age was 51 years (range from 26-82). All of these patients had breast masses; one also had metastasis to the supraclavicular lymph node at the time of diagnosis., mean tumor size was 2.83cm(T2), 23.08%(12/52) was pure invasive micropapillary carcinoma, and lymph node positive percentage was 75.59 %( 36/51).Fifty one patients received surgery, while one of them lost the chance of surgery. Forty of them received the modified mastectomy while one was performed lumpectomy due to old age. One was performed LAND alone and four were performed lumpectomy and sentinel lymph node biopsy.&#x2028; By using IHC staining, when we regard HER2/neu 0 and +as negative. The Luminal A group, Luminal B, trip-negative, HER2+ /ER- were 76.92% (40/52), 11.54 %( 6/52), 7.69 %( 4/52), 3.85 %( 2/52), respectively. Compared to the database of 2005 breast cancer carcinoma in our institution, there was more Luminal A group patients than the whole group (P=0.01, chi-square test.), more Luminal B (P=0.028, Fisher exact possibility test), less trip-negative group (P=0.001, chi-square test). The positive lymph node among the Luminal A group, Luminal B, trip-negative, HER2+ /ER- were 65%,80%, 100%, 100%, respectively, while the lymphvascular invasion were 55%,33.33%,50%,50%,respectively, Mulifocality in Luminal A was 25% , 16.67% in Luminal B , while 50% in both trip-negative and HER2+/ER-.&#x2028; Twenty-one of them received both anthracyclines and Taxane, while 27 only received anthracyclines, Four patients only were received only AIs due to old age. All the luminal group patients received endrocine therapy after chemo. After nearly 14 months (2∼34 months) follow up, thirty-six women were disease free, one had local recurrence, and 1 had lung metastasis, while 1 had ovary carcinoma when the diagnosis of breast malignant, one patient lost following up due to mental disorder. Among the luminal B, one had metastasis when diagnosis, others were disease free. One woman of the trip-negative died of non-breast cancer disease,the HER2+/ER- group was no recurrence or metastasis.&#x2028; Discussion: The prelimary results showed that more luminal group in the IMPC may get benefit from the endocrine therapy. However the number of these cases is small and follow-up time is not very long, further studies are necessary to explain these rare and unique pattern of invasive carcinoma.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 6152.

Seroma formation after breast cancer surgery and its risk factors

Abstract #4085

Background:. Seroma formation is one of the most common complications after breast cancer surgery including modified radical mastectomy and breast conservative surgery. Our study aims to investigate the risk factors of postoperative seroma in Chinese breast cancer patients.&#x2028; Methods: Clinical data of 158 women who underwent surgerical therapy for breast cancer in our hospital were collected prospectively and all patients were followed up. The risk factors for seroma occurrence were compared between the seroma group and control group using X 2 test or t test, as well as the logistic regression was used as multivariate analysis.&#x2028; Results: Univariate analysis showed that the average age of the seroma group was significantly higher than those without seroma formation(58.71vs51.00, P=0.0019), but the total serum protein and albumin content were lower (68.47g/L vs 72.53g/L, P=0.009 and 40.75g/L vs 42.52g/L,P=0.020, respectively). In seroma group, the drainage volume of the first three days, the total and daily drainage volume were all higher (all p values less than 0.01), as well as drainage duration and hospital stay were longer(8.3d vs 14.4d, P=0.000 and 11.5d vs 23.7d, P=0.000, respectively). Logistic regression showed that older patients (OR=1.080, 95%CI 1.016∼1.148, P=0.013), lower total serum protein content(OR=0.814, 95%CI 0.705∼0.940, P=0.005)and higher drainage volume in d1(OR=1.009, 95%CI 1.001∼1.016, P=0.022) and d3 (OR=1.017, 95%CI 1.005∼1.029, P=0.005) were all independent risk factors for subcutaneous seroma. The daily average drainage curve showed a gradually decreasing trend with a highest collections in the first three days. The seroma group had significantly higher average daily drainage volume( P=0.034) and longer duration (P=0.000).&#x2028; Conclusion:The risk factors of seroma formation after breast cancer surgery are complicated. However in order to prevent its occurrence effectively, the factors including age, nutrition status and daily drainage volume should be taken into consideration.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 4085.

Clinicopathological features of the triple-negative tumors in Chinese breast cancer patients

Abstract #6080

Background: Triple negative breast cancers are defined by a lack of expression of estrogen, progesterone, and Her-2 receptors. A number of studies suggested that the triple-negative phenotype could contribute to an aggressive behavior and a poor prognosis. However, similar data is still not available for Chinese populations. We sought to analyze the clinicopathological features of this subgroup in our hospital in order to get characteristics for Chinese breast cancer.&#x2028; Methods: We performed a retrospective study of 2028 female unilateral breast cancer patients undergoing surgery in our hospital from February 1991 to December 2003. ER, PR and Her-2 status were assessed using immunohistochemical staining. Survival curves were performed with Kaplan-Meier method and annual recurrence hazard was estimated by hazard function.&#x2028; Results: According to different combinations of hormone receptor (HR) and Her-2 status, 2028 patients were categorized into the three subgroups as follows: Her-2+ (32.25%), HR+/Her-2- (48.92%) and triple-negative (18.83%). Triple-negative tumors were larger (greater than 2 cm in diameter) than HR+/Her-2- tumors, but smaller than Her-2+ tumors (70.03%, 66.15% and 76.15% respectively, P &lt; 0.001). In addition, 21.99% of patients whose tumors were triple-negative had four or more axillary nodes involved compared with 27.37% of patients with Her-2+ tumors and 22.78% with HR+/Her-2- tumors (P = 0.004). There were statistical differences in the distribution of TP53 mutation and Cathepsin-D status (P &lt; 0.001 for both). In the univariate analysis, we found a statistical significance for recurrence-free survival (RFS) among the three subgroups (P = 0.0036), with the rate of 72.89% for Her-2+ tumors, 78.26% for HR+/Her-2- tumors and 75.61% for triple-negative tumors at the 11th year respectively. When it came to the time of hazard peaks, discrepancies existed in different subgroups. Triple-negative patients showed an early major recurrence surge peaking at the 2.5th year after surgery, followed by a gradual decline until year 6.5 and then a modest increase. As to HR+/Her-2- patients, the hazard plot exhibited a wide initial plateau-like wave covering at least 4 years and a subsequent rise. The hazard rate for Her-2+ patients displayed a tapering sharp at the 1st year and a second rise. Furthermore, the first peak of triple-negative tumors was higher than that of HR+/Her-2- patients, but lower than that of Her-2+ ones.&#x2028; Conclusions: The recurrence pattern for triple-negative tumors was intermediate between Her-2+ and HR+/Her-2- counterparts.Our findings suggested that biological characteristics and prognosis of Chinese triple-negative breast cancer might be more favorable and somewhat different from those in Western populations.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 6080.

The new understanding of two-sided role of glutathione S-transferase M1 in breast cancer susceptibility

Abstract #3098

[Background and purpose] Although glutathione S-transferase M1 (GSTM1) enzyme occupies a key position in biological detoxification processes by catalyzing the glutathione conjugation of carcinogens, GSTM1 gene is genetically deleted (referred as GSTM1-null or GSTM1-/-) in a high percentage of the Eurasian populations. Numerous studies have examined the association of GSTM1-/- with breast cancer yielding inconsistent results. In addition, few genetic variants in this gene have been explored. We set out to systematically evaluate the contributions of GSTM1 gene deletion/presence and common variants in GSTM1 to breast cancer, followed by functional studies.&#x2028; [Methods and Results] In the present study, we show that GSTM1-/- does confer a weak increased risk of breast cancer compared with GSTM1-present genotype, being confirmed by a meta-analysis of combining 40 related studies with the current case-control study (921 cases vs. 711 controls) of Chinese population (overall odds ratio of 1.10, 95% confidence interval: 1.04-1.15, P&lt;0.001). Unexpectedly, GSTM1 homozygous wild-type (+/+) is also associated with a risk of breast cancer compared with heterozygous (+/-) individuals on the basis of accurate classification using long-PCR-based assay. Furthermore, for the population with one allele of GSTM1 (GSTM1+/-) accounting for 30-50%, we genotype four common single nucleotide polymorphisms (SNPs) spanning GSTM1 gene and identify a functional variant g.-498C&gt;G in the putative promoter region associated with breast cancer risk. It displays that minor -498G allele is significantly more frequent in breast cancer controls than in cases (odds ratio of 0.51, 95% confidence interval: 0.30-0.86, P=0.012). This allele also leads to significantly reduced promoter activity compared to the major -498C allele. Further studies reveal the -498G can modify AP-2 binding site and decrease GSTM1 transcription. Among the three AP-2 isoforms, AP-2α provides the predominant regulation effect on this SNP.&#x2028; [Conclusions] These results indicate that the effect of GSTM1 genotypes conferring to breast cancer susceptibility is not dosage-dependent as taken for grant previously. GSTM1 has a two-sided role in breast cancer susceptibility; too high or too low expression of GSTM1 is not beneficial. We recommend that the complicated genetic predisposition of GSTM1 be considered when predicting breast cancer susceptibility using single or a panel of genetic variants.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 3098.

Time distributions and prognosis factors of breast cancer recurrence in different sites after operation

Abstract #2080

Objective Our study aims to analyze the breast caner patients with different sites of recurrence, and to have knowledge of the regular patterns and influence factors of metastastic breast cancer.&#x2028; Methods We performed a retrospective study of 210 female breast cancer patients who were continuously followed up in our hospital from January 2005 to May 2007 and had complete data of metastasis. The clinical and biological characteristics were compared between the patients with organ metastases (lung, liver, brain) and non-viscera metastases (lymph node, bone).&#x2028; Results Cox regression analysis-hazard function showed that patients with elder age (RR=0.927 95%CI 0.877∼0.981, P=0.008) and HER-2 negative(RR=0.253 95%CI 0.076∼0.836, P=0.024)tended to develop non-viscera metastases, while patients with larger tumors (RR=3.832 95%CI 1.073∼13.687, P=0.039) tended to develop organ metastasesp.&#x2028; &#x2028; When stratified by the prognostic factors, the annual risk hazard curve of the patients with high risk of recurrence had double peaks at the second year and the ninth years after mastectomy respectively, and it was significantly higher than those of the patients with middle and low risk.[figure1]Annual risk hazard curves of both local relapse and metastasis also showed a double-peaked pattern. The curves for lymph node, bone, lung and liver metastasis showed a similar pattern, but all the peaks of curve emerged later than that of the local relapse.&#x2028; &#x2028; Conclusion Patients with different clinical and biological characteristics may develop recurrence in different sites. There are certain regular patterns of time distribution for different metastasis sites after mastectomy. The local recurrence may be the foreboding for the metastasis and we should pay attention to the local relapse signs especially in the patients with high risk.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 2080.

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Genetic Polymorphisms in the DNA Repair Enzyme ERCC2 and Breast Tumour Risk in a Chinese Population

DNA repair systems enable our cells to respond to carcinogens and mutagens. The ERCC2 gene encodes a DNA repair protein that has multiple regulatory cellular functions including nucleotide excision repair, basal transcription, cell cycle control, and apoptosis. The ERCC2 polymorphism Lys751Gln may alter the capacity for DNA repair, which could affect the risk of certain cancers. We examined whether the Lys751Gln polymorphism was associated with the risk of breast cancer in Chinese women by analysing the genotype frequencies in 486 patients with breast cancer and 479 cancer-free control subjects. At least one variant allele (Lys/Gln or Gln/Gln) was associated with a 44% decreased risk of breast cancer. Patients with breast cancer with the 751Lys/Gln or 751Gln/Gln genotypes were less likely to be hormone receptor positive. In conclusion, our results demonstrated that ERCC2 polymorphisms might be potential risk markers for breast cancer in the Chinese population.

A comparison of tumor characteristics between ER+/PR+ and ER+/PR- breast tumors in Chinese women

21097

Background: Although breast caner patients with any one of the two sex hormone receptors positive can be treated with endocrine therapy, many clinical data showed that there was different response to endocrine therapy for patients with ER+/PR+ and with ER+/PR- tumors. The aim of this study was to find out the factors related to PR expression by comparing the ER+/PR+ tumors and ER+/PR- tumors clinically and biologically. Methods: Between January 1990 to August 2006, 5,191 female breast cancer patients with known ER/PR expression status who received operation in our hospital were enrolled onto this retrospective study. Clinical and biological features of 2,227 patients with ER+/PR+ tumors were compared with those of 909 patients with ER+/PR- tumors. χ2 test was used for univariate analysis and logistic regression for multivariate analysis. Disease-free survival (DFS) and overall survival (OS) was calculated using Kaplan-Meier analyses, and all statistical tests were two-sided. Results: The peak onset age of patients with ER+/PR+ tumors and ER+/PR- tumors was 50, and it was significantly higher than that of patients with ER- tumors, which is 48(P=0.001). Univariate analysis showed that ER+/PR- tumors were larger in size, had more lymph nodes of metastasis, were higher in tumor grade than ER+/PR+ tumors. Furthermore, the expression of ER and CathepsinD was significantly lower, and CerbB-2 expression was higher in ER+/PR- tumors than in ER+/PR+ tumors. Multivariate analysis indicated that positive PR expression was associated with the level of ER(OR=1.792, P=0.000), CathepsinD(OR=1.380, P=0.035)and CerbB-2(OR=0.639, P=0.007). DFS(P=0.004) and OS(P=0.009) were higher among patients with PR-expressing tumors than with PR- negative tumors. Conclusions: ER+/PR+ tumors and ER+/PR- tumors may have the same etiology which is different from that of ER- tumors. Because of low ER level and changes of the expression of CerbB-2 and CathepsinD, the tumors that lacked PR expression display more aggressive features and have worse prognosis. According to these differences, new target of therapy and endocrine regimen may provide the possibility of improving the response and prognosis of endocrine therapy for patients with ER+/PR- tumors.

No significant financial relationships to disclose.

The rule of mortality risk in young women (≤35 years) with primary breast cancer

21098

Background: The prognosis of young women (=35 years) is poorer than that of women over 35 years, which may indicate that they bear different biologic characteristics. However, such data is still not available at home and abroad as the rule of mortality risk in young women and its distinction from that in women over 35 years. We sought to investigate the clinical characteristics, prognosis and the rule of mortality risk in young women (=35 years) with primary breast cancer. Methods: We performed a retrospective study of 2331 female unilateral breast cancer patients undergoing surgery in our hospital from January 1990 to October 2005.They were divided into two groups with the cut-off of 35 years. Selection criteria included complete data on the following: age, tumor size, axillary nodal status, estrogen receptor (ER) status, menopausal status.Overall survival curve was estimated by Kaplan-Meier method and annual mortality hazard by hazard function. Their clinicopathologic indices, overall survival curve and annual mortality hazard were analyzed. Results: There was statistical significance between =35 years and >35 years group in terms of tumor size( P =0.0231), axillary nodal status( P <0.001) and estrogen receptor status( P =0.064). 10-year overall survival was 72% and 79% ( P = 0.0081), respectively, for =35 years and >35 years group. Although annual mortality hazard curve for both groups showed double-peaked pattern, there also exist some differences. Mortality surges for =35 years patients appeared earlier than those for >35 years counterparts. Moreover, =35 years group showed a minor increase between double peaks, which cannot be found in >35 years group. Conclusions: Between the two groups, different tumor biology leads to the discrepancy of overall survival and mortality pattern, which might indicate distinct principles and measures in the follow-up and treatment for young patients to provide the possibility of improving the therapeutic effect and reducing the mortality hazard.

No significant financial relationships to disclose.

Culturally appropriate measures for monitoring child development at family and community level: a WHO collaborative study

Culturally appropriate techniques for monitoring child psychosocial development were prepared and tested in China, India and Thailand on a total of 28,139 children. This is the largest study of its kind ever undertaken. Representative groups aged between birth and 6 years were examined and the results were used to produce national development standards-separately for rural and urban children in China and India, and for all children combined in Thailand-which are considered to be more satisfactory than foreign-based standards. In each country, between 13 and 19 key milestones of psychosocial development were selected for a simplified developmental screening operation and these have been incorporated on a home-based record of a child's growth and development. Between 35 and 67 tests have been devised in each country to test the children at first-referral level.

A two-level cross-sectional model using grafted polynomials

A new statistical model is proposed for the analysis of hierarchically structured cross-sectional growth data, especially for where measurements are made over long age ranges. The model combines a two-level model with grafted piecewise polynomials, to make efficient use of available data.