miR-638 Serves as a Biomarker of 5-Fluorouracil Sensitivity to Neoadjuvant Chemotherapy in Breast Cancer / 한국유방암학회지

Purpose@#Neoadjuvant chemotherapy (NAC) is widely used to treat breast cancer (BC). The prediction and evaluation of chemotherapy responses remains a significant challenge. @*Methods@#MicroRNAs (miRNAs) play a crucial role in cancer drug resistance. We used a miRNA microarray and identified that miR-638 is downregulated in chemoresistant cases.However, the exact role of miR-638 and the underlying mechanisms of chemoresistance remain unclear. Using real-time quantitative reverse transcription polymerase chain reaction, we found significant downregulation of miR-638 in chemoresistant patients compared with chemosensitive patients. To explore the function of miR-638, we overexpressed and inhibited miR-638 expression in MDA-MB-231 and MCF-7 cells by transfecting them with miR-638 mimics and miR-638 inhibitor, respectively. Cell proliferation and apoptosis were measured using MTS and flow cytometry, respectively. A minimal patient-derived xenograft (MiniPDX™) model was established to evaluate the chemosensitivity to different drugs. @*Results@#The results showed that cell proliferation decreased and cell apoptosis increased in cells transfected with the miR-638 mimic, and cell proliferation and apoptosis were reversed with transfection of miR-638 inhibitor compared with the control group. Among patients who received 5-fluorouracil (5-FU), miR-638 expression levels were lower in the chemoresistant group than in the chemosensitive group. The MiniPDX™ model showed that MDA-MB-231 cells overexpressing miR-638 were more susceptible to 5-FU treatment in vivo. @*Conclusion@#We provided evidence of acquired resistance to 5-FU caused by miR-638 deficiency. Alterations in miR-638 may be used with 5-FU chemotherapy during NAC for BC.

Protective effect of dexrazoxane on cardiotoxicity in breast cancer patients who received anthracycline-containing chemotherapy / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To evaluate the cardioprotective effects of dexrazoxane (DEX) on breast cancer patients who received anthracycline-containing chemotherapy.</p><p><b>METHODS</b>A total of 122 breast cancer patients after operation were randomly divided into two groups: The experimental group of 61 cases treated with EPI plus DEX (DEX:EPI = 10:1) as adjuvant chemotherapy regimen, and the control group of 61 cases treated with EPI but without DEX. All patients received four cycles of adjuvant chemotherapy and their changes of specific cardiac functional status and hematology status before and after chemotherapy, as well as non-cardiac toxicity were observed and analyzed.</p><p><b>RESULTS</b>Brain natriuretic peptide (BNP) before chemotherapy and after four cycles of chemotherapy in the control group was (106.78 ± 4.52)×10(-6) µg/ml and (187.19 ± 8.71)×10(-6) µg/ml, respectively, with a significant difference between them (P < 0.05). It in the experimental group was (102.34 ± 8.76)×10(-6) µg/ml and (105.29 ± 7.21)×10(-6) µg/ml, respectively, without a significant difference (P > 0.05). Cardiac troponin T (cTnT) before chemotherapy and after four cycles of chemotherapy in the control group was (12.55 ± 2.73)×10(-3) µg/ml and ( 31.05 ± 7.10 )×10(-3) µg/ml, respectively, with a significant difference between them (P < 0.05). It in the experimental group was (12.70 ± 2.15)×10(-3) µg/ml and (13.65 ± 7.82)×10(-3) µg/ml, respectively, without a significant difference (P > 0.05). The hart rate (HR) before chemotherapy and after four cycles of chemotherapy in the control group, was 75.32 ± 7.14 bpm and 89.60 ± 9.21 bpm, respectively, with a significant difference (P < 0.05). It in the experimental group was 78.60 ± 6.29 bpm and 83.10 ± 7.56 bpm, respectively, without a significant difference (P > 0.05). The left ventricular ejection fraction (LVEF) before chemotherapy and after four cycles of chemotherapy in the control group was (65.23 ± 7.82)% and (55.21 ± 7.23)%, respectively, with a significant difference between them (P < 0.05). It in the experimental group was (64.12 ± 6.25)% and (59.6 ± 4.72)%, respectively, without a significant difference (P > 0.05). The absolute neutrophil count before chemotherapy and after four cycles of chemotherapy in the control group was (3.95 ± 1.36)×10(9)/L and (3.50 ± 1.52)×10(9)/L, respectively, without a significant difference (P > 0.05). It in the experimental group, was (4.96 ± 1.41)×10(9)/L and (3.10 ± 1.26)×10(9)/L, respectively, with a significant difference (P < 0.05). The incidence of grade I-IV bone marrow suppression in the experimental group was 21.3%, 16.4%, 24.6%, and 4.9%, respectively. It in the control group was 16.4%, 11.5%, 9.8%, and 5.5%, respectively, with a significant difference (P < 0.05).</p><p><b>CONCLUSIONS</b>Cardiac toxicity after anthracycline treatment in breast cancer patients may be significantly reduced by DEX, without increase of non-cardiac and and non-hematologic toxicity. DEX combined with anthracycline increases the risk of bone marrow suppression, therefore, peripheral blood picture should be monitored or routine bone marrow support may be needed.</p>

Comparison of tolerance and toxicity of CEF-100 regimen versus CEF-60 regimen as adjuvant therapy for breast cancer / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To evaluate tolerance and toxicity of high-dose epirubicin regimen CEF-100 as adjuvant therapy for breast cancer.</p><p><b>METHODS</b>From March 2005 to October 2006, 98 patients with stage I - III a breast cancer were randomly assigned to receive postoperative chemotherapy with CEF-100 regimen (epirubicin 100 mg/m2, dl per 21 days for 6 cycles, n =48) or CEF-60 regimen (epirubicin 60 mg/m2, dl per 21 days for 6 cycles, n = 50). Blood routine test were done every cycle, liver and kindey function were examined and adverse effects were recorded after every cycle.</p><p><b>RESULTS</b>No difference of average leucocyte or neutrophil count (P >0.05) was observed in every cycle. Adverse effects of digestive tract and damage of liver function in CEF-100 group were more severe than that in CEF-60 group (P <0.05), but all adverse effects could be relieved by treatment. No severe non-hematological toxicity and cardiac toxicity in both groups were observed (P <0.05). There was no death caused by chemotherapy.</p><p><b>CONCLUSION</b>Our data shows that high dose epirubicin-containing CEF regimen is safe and tolerable for postoperative chemotherapy of breast cancer patient, and the adverse effects could be relieved by marrow support and liver-protection therapy. Further observation and longer follow-up is still needed in order to evaluate the efficacy of this high dose regimen.</p>