Xinmei Kang

Daidzein induces MCF-7 breast cancer cell apoptosis via the mitochondrial pathway

BACKGROUND In order to study the anticancer effects and cellular apoptosis pathways induced by daidzein. MATERIALS AND METHODS We used the human MCF-7 breast cancer cell line as a model and examined the apoptosis by Hoechst-propidium iodide staining fluorescence imaging and flow cytometry. RESULTS Our data indicated that daidzein induces antiproliferative effects in a concentration- and time-dependent manner. We demonstrated that daidzein-induced apoptosis in MCF-7 cells was initiated by the generation of reactive oxygen species (ROS). Furthermore, we showed that this daidzein-induced ROS generation was accompanied by disruption of mitochondrial transmembrane potential, down-regulation of bcl-2, and up-regulation of bax, which led to the release of cytochrome C from the mitochondria into the cytosol, which, in turn, resulted in the activation of caspase-9 and caspase-7, and ultimately in cell death. The induction of the mitochondrial caspase-dependent pathway was confirmed by pretreatment with pan-caspase inhibitor z-VAD-fmk and antioxidant N-acetyl-L-cysteine. CONCLUSION Accordingly, daidzein could induce breast cancer cell apoptosis through the mitochondrial caspase-dependent cell death pathway.

Effect of soy isoflavones on breast cancer recurrence and death for patients receiving adjuvant endocrine therapy

Background: The intake of soy isoflavones among women with breast cancer has become a public health concern, because these compounds have weak estrogenic effects. There is little clinical evidence about their safety for patients with breast cancer who are receiving adjuvant endocrine therapy. Methods: For patients who underwent surgery for breast cancer between August 2002 and July 2003 and who were receiving adjuvant endocrine therapy, we examined associations between dietary intake of soy isoflavones and recurrence of breast cancer and death. We measured dietary intake of soy isoflavones at baseline using a validated food frequency questionnaire. We estimated hazard ratios (HRs) and 95% confidence intervals (CIs) by means of multivariable Cox proportional hazards regression models. We further stratified the analyses by hormonal receptor status and endocrine therapy. Results: The median follow-up period for the 524 patients in this study was 5.1 years. Among premenopausal patients, the overall death rate (30.6%) was not related to intake of soy isoflavones (HR = 1.05, 95% CI 0.78–1.71 for the highest quartile [> 42.3 mg/day] v. the lowest quartile [< 15.2 mg/day], p for trend = 0.87). Relative to post-menopausal patients in the lowest quartile of soy isoflavone intake, the risk of recurrence for post-menopausal patients in the highest quartile was significantly lower (HR = 0.67, 95% CI 0.54–0.85, p for trend = 0.02). Inverse associations were observed in patients with estrogen and progesterone receptor positive disease and those receiving anastrozole therapy. Interpretation: High dietary intake of soy isoflavones was associated with lower risk of recurrence among post-menopausal patients with breast cancer positive for estrogen and progesterone receptor and those who were receiving anastrozole as endocrine therapy.

Antiangiogenic Effect of Capecitabine Combined with Ginsenoside Rg3 on Breast Cancer in Mice

Capecitabine is a novel fluoropyrimidine carbamate, which has a broader spectrum of antitumor activity than other fluoropyrimidines, such as 5-FU, DFUR, or UFT; it has proved effective over a wide dose range. Recent research has suggested that frequent administration of lower doses of certain chemotherapeutic drugs might enhance their antiangiogenic effect. The present study investigated the antiangiogenic effect of capecitabine on breast cancer. In order to augment its efficacy, we combined capecitabine chemotherapy with ginsenoside Rg3. Our results indicate that a metronomic regimen of capecitabine inhibited angiogenesis in breast cancer, and its antiangiogenic effects may be further enhanced by the concurrent administration of ginsenoside Rg3. As an antiangiogenic method, this regimen presented better antitumor effects, less toxicity, and reduced susceptibility to drug resistance.

The expression and clinical significance of microRNA-1258 and heparanase in human breast cancer

OBJECTIVES To investigate the expression profile of miR-1258 and heparanase (HPSE) in breast cancer and to assess their clinicopathological significance. DESIGN AND METHODS The expression levels of miR-1258 and HPSE were analyzed in normal, benign and malignant breast tissues. Their serum levels were evaluated in healthy women and in patients with benign and malignant breast disease. We studied the correlation between the expression of miR-1258 and HPSE and the clinical features presented by the patients. RESULTS MiR-1258 was down-regulated and HPSE was up-regulated in breast cancer, with a significant inverse correlation. A reduced miR-1258 expression and an elevated HPSE expression were associated with the lymph node status, late clinical stages, a short overall survival and a short relapse-free survival. In frozen fresh tissue samples, the miR-1258 levels in breast cancer with lymph node metastasis were significantly lower than that of breast cancer without lymph node metastasis and benign disease (BD). In contrast, the HPSE levels in breast cancer with lymph node metastasis were the highest. In serum samples, the miR-1258 levels in metastatic breast cancer (M1) were lower than that of primary breast cancer (M0) and BD. However, serum HPSE levels of M1 patients were significantly higher than that of M0 patients and BD patients. CONCLUSIONS MiR-1258 may play an important role in breast cancer development and progression by regulating the expression of HPSE, and they might be potential prognostic biomarkers for breast cancer.

Spore Powder of Ganoderma lucidum Improves Cancer-Related Fatigue in Breast Cancer Patients Undergoing Endocrine Therapy: A Pilot Clinical Trial.

The fatigue prevalence in breast cancer survivors is high during the endocrine treatment. However, there are few evidence-based interventions to manage this symptom. The aim of this study was to investigate the effectiveness of spore powder of Ganoderma lucidum for cancer-related fatigue in breast cancer patients undergoing endocrine therapy. Spore powder of Ganoderma lucidum is a kind of Basidiomycete which is a widely used traditional medicine in China. 48 breast cancer patients with cancer-related fatigue undergoing endocrine therapy were randomized into the experimental or control group. FACT-F, HADS, and EORTC QLQ-C30 questionnaires data were collected at baseline and 4 weeks after treatment. The concentrations of TNF-α, IL-6, and liver-kidney functions were measured before and after intervention. The experimental group showed statistically significant improvements in the domains of physical well-being and fatigue subscale after intervention. These patients also reported less anxiety and depression and better quality of life. Immune markers of CRF were significantly lower and no serious adverse effects occurred during the study. This pilot study suggests that spore powder of Ganoderma lucidum may have beneficial effects on cancer-related fatigue and quality of life in breast cancer patients undergoing endocrine therapy without any significant adverse effect.

AIB1 is required for the acquisition of epithelial growth factor receptor-mediated tamoxifen resistance in breast cancer cells.

Acquired resistance to tamoxifen has become a serious obstacle in breast cancer treatment. The underlying mechanism responsible for this condition has not been completely elucidated. In this study, a tamoxifen-resistant (Tam-R) MCF-7 breast cancer cell line was developed to mimic the occurrence of acquired tamoxifen resistance as seen in clinical practice. Increased expression levels of HER1, HER2 and the estrogen receptor (ER)-AIB1 complex were found in tamoxifen-resistant cells. EGF stimulation and gefitinib inhibition experiments further demonstrated that HER1/HER2 signaling and AIB1 were involved in the proliferation of cells that had acquired Tam resistance. However, when AIB1 was silenced with AIB1-siRNA in Tam-R cells, the cell growth stimulated by the HER1/HER2 signaling pathway was significantly reduced, and the cells were again found to be inhibited by tamoxifen. These results suggest that the AIB1 protein could be a limiting factor in the HER1/HER2-mediated hormone-independent growth of Tam-R cells. Thus, AIB1 may be a new therapeutic target, and the removal of AIB1 may decrease the crosstalk between ER and the HER1/HER2 pathway, resulting in the restoration of tamoxifen sensitivity in tamoxifen-resistant cells.

Factors associated with cancer-related fatigue in breast cancer patients undergoing endocrine therapy in an urban setting: a cross-sectional study

BackgroundFatigue is prevalent in breast cancer survivors and has profound effects on daily life. The interference of fatigue with endocrine therapy may be difficult to separate. This study investigates the prevalence and severity of fatigue and identifies the demographic, clinical, and lifestyle factors associated with cancer-related fatigue (CRF) in breast cancer patients undergoing endocrine therapy in an urban area.MethodsWomen with stage I-IIIA breast cancer were recruited and asked to participate (n = 371) in the study. The 315 women who responded to the questionnaire (84.9%), 54 (17.1%) had completed endocrine therapy and 261 (82.9%) were still undergoing endocrine therapy. The patients had been diagnosed at an average of 31 months prior to recruitment (range, 7 to 60 months); the average age was 48 (range, 33 to 72) years. The 11-point scale and Visual Analog Scale (VAS) were employed to quantify the level of fatigue experienced by the patients. Logistic regression analyses and a trend test method were performed to evaluate factors associated with CRF.ResultsAmong the 315 patients, 189 (60%) had experienced or were experiencing CRF during endocrine therapy. Logistic regression analysis was performed to identify factors associated with CRF, including BMI (body mass index), clinical stage, menopausal status, duration of endocrine therapy, physical activity, and diet. Factors unrelated to CRF were age, marital status, treatment, endocrine therapy drugs, alcohol intake, and smoking. The trend test method revealed an association between physical activity and dietary level and the intensity of CRF.ConclusionsThe present findings suggest that fatigue is an important problem in the majority of breast cancer patients during endocrine therapy. We found that BMI, clinical stage, menopausal status, duration of endocrine therapy, physical activity, and diet are associated with fatigue. Future research should focus on the impact factors of CRF and lifestyle in the management of breast cancer patients.

Altered glycometabolism affects both clinical features and prognosis of triple-negative and neoadjuvant chemotherapy-treated breast cancer

Glycometabolism is a distinctive aspect of energy metabolism in breast cancer, and key glycometabolism enzymes/pathways (glycolysis, hexosamine biosynthetic pathway, and pentose phosphate pathway) may directly or indirectly affect the clinical features. In this study, we analyzed the particular correlation between the altered glycometabolism and clinical features of breast cancer to instruct research and clinical treatment. Tissue microarrays containing 189 hollow needle aspiration samples and 295 triple-negative breast cancer tissues were used to test the expression of M2 isoform of pyruvate kinase (PKM2), glutamine-fructose-6-phosphate transaminase 1 (GFPT1), glucose-6-phosphate dehydrogenase (G6PD), and p53 by immunohistochemistry and the intensity of these glycometabolism-related protein was evaluated. Chi-square test, Kaplan-Meier estimates, and Cox proportional hazards model were used to analyze the relationship between the expression of these factors and major clinical features. PKM2, GFPT1, and G6PD affect the pathologic complete response rate of neoadjuvant chemotherapy patients in different ways; pyruvate kinase muscle isozyme 2 (PKM2) and G6PD are closely associated with the molecular subtypes, whereas GFPT1 is correlated with cancer size. All these three factors as well as p53 have impacts on the progression-free survival and overall survival of triple-negative breast cancer patients. Cancer size shows significant association with PKM2 and GFPT1 expression, while the pN stage and grade are associated with PKM2 and G6PD expression. Our study support that clinical characteristics are reflections of specific glycometabolism pathways, so their relationships may shed light on the orientation of research or clinical treatment. The expression of PKM2, GFPT1, and G6PD are hazardous factors for prognosis: high expression of these proteins predict worse progression-free survival and overall survival in triple-negative breast cancer, as well as worse pathologic complete response rate in neoadjuvant chemotherapy breast cancer. However, p53 appears as a protective factor only in the patients receiving neoadjuvant chemotherapy. All the four proteins, PKM2, GFPT1, G6PD and p53, are prognostic markers of breast cancer. The correlation among them suggests that there may be crosstalk of the four proteins in breast cancer.

Photothermal therapeutic application of gold nanorods-porphyrin-trastuzumab complexes in HER2-positive breast cancer

Gold nanorods are effective photothermal agents in diagnosis and treatment of cancer due to their specific near-infrared laser absorption. However, tumor photothermal therapy by nanorods alone is lack of targeting. Here, we described a novel nanocomplex made up of gold nanorods, porphyrin, and trastuzumab, called TGNs and investigated the TGN-mediated photothermal therapy as a potential alternative treatment of targeting HER2-positive breast cancers. By conjugating trastuzumab and porphyrin to the surface of gold nanorods, we have increased the targeting specificity and amplified the detecting effectiveness at the same time. TGN-mediated photothermal ablation by near-infrared laser led to a selective destruction of HER2-positive cancer cells and significantly inhibited tumor growth in mouse models bearing HER2 over-expressed breast cancer xenograft with less toxicity. Moreover, TGNs provided better therapeutic efficacy in comparison with the conventional molecule targeted therapy. Our current data suggest a highly promising future of TGNs for its therapeutic application in trastuzumab-resistant breast cancers.

Malignant melanoma therapy by chemotherapy and autoimmunity induced by cytokine.

PURPOSE The aim of this study was to evaluate the effect of combining dacarbazine (DTIC) and granulocyte/macrophage colony-stimulating factor (GM-CSF) with interleukin-2 (IL-2) in patients with advanced malignant melanoma. METHODS Twenty-seven (27) patients with advanced malignant melanoma received dacarbazine (500 mg/m(2)/days 1-2, intravenously), GM-CSF (175 ug/m(2)/days 3-6, subcutaneously), and interleukin-2 (400 MIU/m(2)/days 7-10, subcutaneously). Each treatment cycle required 21 days to completion. RESULTS Time to progression was 7-11 months. The total effective rate was 44.4%, and the combination of chemotherapy, GM-CSF, and IL-2 had low toxicity. CONCLUSIONS The combination of DTIC with GM-CSF and IL-2 is feasible and possibly efficacious for clinical use.