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.

Coexpression and Synergistic Role of Multiple Atypical Chemokine Binders in Breast Cancer

Background: The expression and role of Duffy antigen receptor for chemokine (DARC), D6 and ChemoCentryx chemokine receptor (CCX-CKR) in breast cancer have already been studied independently in the past several years. However, the relationship and importance of these atypical chemokine binders (ACB) are still unclear. In this large scale clinical study, we invastigated the characteristics of multiple ACB simultaneously. Material and Methods: The protein levels of DARC, D6 and CCX-CKR were analyzed by immunohistochemistry in 517 patients with invasive breast cancer, 29 patients with noninvasive breast cancer. All of these cases come from the Cancer Hospital of Fudan University during 2001-2006, with complete clinicopathological data and follow-up data, including survival information. Results: In the invasive breast cancer patients, triple, double and single positive expression of these ACB were 135 cases (26.1%), 154 cases (29.8%) and 121 cases (23.4%), respectively. On the other hand, 107 cases (20.7%) were complete negative. The triple positive staining was significantly conversely correlated with lymph node metastasis, disease stage, relapse-free survival (RFS) as well as overall survival (OS). DARC, D6, and CCX-CKR were independent factors that influenced lymph node metastasis and their coexpression was favorable prognostic factor for RFS and OS. Discussion: Our results confirmed that DARC, D6, and CCX-CKR play a negative role in breast cancer. Furthermore, their triple or double high coexpression is more favorable for the patients, suggesting that multiple ACB may provide better protection against metastasis and relapse by synergistically regulating chemokine network in breast cancer.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 4166.

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.

Overexpression or Lack of beta 2-Adrenergic Receptor Correlate with Progression of Breast Cancer

Background: Recent studies showed that stress can modulate biological behavior of ovarian carcinoma through adrenergic receptors. Since both nonselective beta-adrenergic receptor antagonist propranolol and selective beta 2-adrenergic receptor (b2AR) antagonist ICI 118,551 instead of b1AR antagonist atenolol could eliminate most of the effects, b2AR is accordingly regarded as the key molecule. In this study, we investigated the role of b2AR in breast cancer. Material and Methods: Gene expression of b2AR was analyzed by RT-PCR in human breast cancer cell lines MDA-MB-231, MDA-MB-435, MDA-MB-468, MCF-7, T47D, BT-549, HCC1937, BCaP-37 and normal mammary epithelial-like cell line HBL-100. b2AR cDNA was transfected into MDA-MB-435 cells. Protein level of b2AR was analyzed by immunohistochemistry in clinical samples, including 25 normal human breast or benign disease breast tissues and 202 breast cancer tissues. Results: b2AR was detected in majority of breast cancer cell lines, except for MDA-MB-435, MCF-7 and T47D, and all of normal or benign disease breast tissues. Both nonselective beta-adrenergic receptor agonist norepinephrine (NE) and selective b2AR agonist terbutaline promoted proliferation and invasion of spontaneous b2AR-positive MDA-MB-231 cells and transfectant MDA-MB-435-b2AR cells, these effects were completely inhibited by selective b2AR antagonist ICI 118,551. In the breast cancer patients, 125 samples (61.9%) expressed b2AR weakly or moderately just as normal breast or benign diseases tissue, and 43 (21.3%) presented significantly stronger b2AR expression, while no b2AR staining was found in other 34 samples (16.8%). Higher expression or lack of b2AR were associated with axillary lymph nodes metastasis and poor disease free survival (DFS). Discussion: Based on our preliminary results, the breast cancer patients could be classified into three subgroups: b2AR “normal”, high expression and negative groups. Overexpression or lack of b2AR associated with metastasis and clinical prognosis in breast cancer. Obviously, abnormal expression of b2AR may influence the outcome of breast cancer.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 4165.

Changing Patterns and Present Status of Female Breast Cancer in China over 30 Years

Introduction: As a metropolis with rapid social and economic development over the past three decades, Shanghai has a breast cancer incidence that surpasses all other cancer registries in China.Methods: In order to estimate the regular changing patterns of female breast cancer in urban Shanghai, population-based incidence data from 1975 to 2004 were studied. In addition, a one-hospital-based in-patient database of 9709 female breast cancer patients treated surgically between Jan-1990 and Dec-2008 were reviewed, retrospectively.Results: We observed that breast cancer incidence increased dramatically over the past 30 years and documented a peak incidence represented by the middle-age group (45-59 yrs), which emerged in the last 20 years. The incidence peak moved from the 40-44 year group in the previous two decades to the 50-54 year group in the most recent decade. Median age at diagnosis was earlier in Shanghai than in the western countries, although it increased from 47.5-yr in 1990 to 51-yr in 2008. Considerably higher exposure to reproductive risk factors and relatively fewer hormone-dependent cases were observed- only 49.2% of breast cancers were estrogen receptor(ER) positive, 46.1% were progesterone receptor positive. The proportion of asymptomatic cases detected by screening gradually increased, as well as that of early-stage cases (from 78.6% in 1990 to 87.9% in 2008 and carcinoma in situ (14.9% in 2008). Analysis of surgical treatment patterns suggested a trend of less-invasive options.Conclusions: Rapid socioeconomic growth and birth-control policies have revealed some unique risk factors, which pushed the pattern of breast cancer in Shanghai towards that of the western countries. Age of peak incidence as well as median age at diagnosis increase with time, which suggests that increased incidence trending along with increasing age will be observed in the future. The middle-age group born after 1950s would be involved in current birth-control policies and they are also the cohorts related to the incidence boom. Thus specific screening protocols should be refined for the Chinese population, considering not only increasing age but also birth cohorts. Improvements in breast cancer detection provide patients with more opportunities for less invasive treatment options.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 2058.

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.

Antigens containing TAVSPTTLR tandem repeats could be used in assaying antibodies to Classical swine fever virus

Classical swine fever virus (CSFV) causes a highly contagious and often fatal viral disease in pigs. The highly conserved epitope TAVSPTTLR on the glycoprotein E2 was shown to be suitable for differentiation of CSFV from other pestiviruses. In this study, we found that swine CSFV antisera contained TAVSPTTLR-related rather than TAVSPTTLR-specific CSFV antibodies. The CSFV antisera reacted only to some extent with a synthetic TAVSPTTLR-containing peptide, but inhibited the binding of TAVSPTTLR-specific antibodies to the viral antigen. Since chimeric antigens containing TAVSPTTLR tetramers or hexamers were recognized by the swine CSFV antisera, such antigens could be potentially applied to the detection of CSFV antibodies. These results might be helpful in designing a TAVSPTTLR epitope-based CSFV vaccine and a corresponding serological test.

Activation of complement in the discordant heart xenotransplantation of pig-to-monkey model and the impact of intrathymic inoculation of xenogeneic antigen combined with whole-body gamma-radiation

OBJECTIVE

This study investigated changes in complement in discordant heart xenotransplantation using a pig-to-monkey model as well as the impact of intrathymic inoculation (IT) with xenogeneic antigen combined with whole-body gamma-radiation (WBI).

METHODS

In this experiment, pigs and monkeys selected as donors and recipients, respectively, were randomly divided into three groups: a blank group (group A), a whole-body irradiation group (group B) and an irradiation plus intrathymic injection group (group C). In every group, monkeys underwent heterotopic heart xenotransplantation.

RESULTS

The results showed that the survival of donor hearts in group C was significantly longer than that of group A (P < .01). In mixed lymphocyte reactions, there was a significant reduction of the stimulation index in group C compared with group A. After xenotransplantation, the level of xenoreactive antibody in group C rose slower than that in group A or group B (P < .01). After rejection, the levels of CD46 and C3 declined greatly.

CONCLUSIONS

These results suggested that pretreatment with IT and WBI induced T-cell immunosuppression, restraining elicited xenoreactive antibody production of both immunoglobulin M and immunoglobulin G classes. However, it did not hinder complement activation via the classical pathway during hyperacute rejection and consequent xenograft rejection.

Chronic hepatitis, hepatic dysplasia, fibrosis, and biliary hyperplasia in hamsters naturally infected with a novel Helicobacter classified in the H. bilis cluster

We recently described helicobacter-associated progressive, proliferative, and dysplastic typhlocolitis in aging (18- to 24-month-old) Syrian hamsters. Other pathogens associated with typhlocolitis in hamsters, Clostridium difficile, Lawsonia intracellularis, and Giardia spp., were not indentified. The presence of Helicobacter genus-specific DNA was noted by PCR in cecal and paraffin-embedded liver samples from aged hamsters by the use of Helicobacter-specific PCR primers. By 16S rRNA analysis, the Helicobacter sp. isolated from the liver tissue was identical to the cecal isolates from hamsters. The six hamster 16S rRNA sequences form a genotypic cluster most closely related to Helicobacter sp. Flexispira taxon 8, part of the Helicobacter bilis/H. cinaedi group. Livers from aged helicobacter-infected hamsters showed various stages of predominantly portocentric and, to a lesser extent, perivenular fibrosis. Within nodules, there was cellular atypia consistent with nodular dysplasia. The livers also exhibited a range of chronic active portal/interface and lobular inflammation, with significant portal hepatitis being present. The inflammation was composed of a mixture of lymphocytes, neutrophils, and macrophages, indicative of its chronic-active nature in these aged hamsters infected with Helicobacter spp. The isolation of novel Helicobacter spp., their identification by PCR from the diseased livers of aged hamsters, and their taxonomic classification as belonging to the Helicobacter bilis cluster strengthen the argument that H. bilis and closely related Helicobacter spp. play an etiological role in hepatobiliary disease in both animals and humans.