SCD1 activity promotes cell migration via a PLD-mTOR pathway in the MDA-MB-231 triple-negative breast cancer cell line.

BACKGROUND: Breast cancer is the most common cancer in women. Despite high survival rates in Western countries, treatments are less effective in metastatic cases and triple-negative breast cancer (TNBC) patient survival is the shortest across breast cancer subtypes. High expression levels of stearoyl-CoA desaturase-1 (SCD1) have been reported in breast cancer. The SCD1 enzyme catalyzes the formation of oleic acid (OA), a lipid stimulating the migration of metastatic breast cancer cells. Phospholipase activity is also implicated in breast cancer metastasis, notably phospholipase D (PLD). METHODS: Kaplan-Meier survival plots generated from gene expression databases were used to analyze the involvement of SCD1 and PLD in several cancer subtypes. SCD1 enzymatic activity was modulated with a pharmaceutical inhibitor or by OA treatment (to mimic SCD1 over-activity) in three breast cancer cell lines: TNBC-derived MDA-MB-231 cells as well as non-TNBC MCF-7 and T47D cells. Cell morphology and migration properties were characterized by various complementary methods. RESULTS: Our survival analyses suggest that SCD1 and PLD2 expression in the primary tumor are both associated to metastasis-related morbid outcomes in breast cancer patients. We show that modulation of SCD1 activity is associated with the modification of TNBC cell migration properties, including changes in speed, direction and cell morphology. Cell migration properties are regulated by SCD1 activity through a PLD-mTOR/p70S6K signaling pathway. These effects are not observed in non-TNBC cell lines. CONCLUSION: Our results establish a key role for the lipid desaturase SCD1 and delineate an OA-PLD-mTOR/p70S6K signaling pathway in TNBC-derived MDA-MB-231 cell migration.

Anthracycline could be essential for triple-negative breast cancer: A randomised phase II study by the Kanagawa Breast Oncology Group (KBOG) 1101.

BACKGROUND: It is important to determine whether anthracycline-containing regimens or taxane-containing regimens are more effective in individual patients. The present study compared the efficacy of six cycles of docetaxel and cyclophosphamide (TC6) with that of three cycles of 5-fluorouracil, epirubicin and cyclophosphamide followed by docetaxel (FEC-D) in Japanese patients with hormone receptor (HR)-negative breast cancer (BC) to identify subtypes requiring anthracycline treatment. METHODS: The study included 103 patients with operable HR-negative BC. Of these patients 53 received FEC-D and 50 received TC6. The primary endpoint was pathological complete response (pCR). The secondary endpoints were safety, breast-conserving surgery, disease-free survival (DFS) and overall survival (OS). The predictive factors for each regimen were evaluated. RESULTS: Of the 103 patients, 97 completed the study (FEC-D, 50 patients; TC6, 47 patients). The pCR rate was higher with FEC-D (36%) than with TC6 (25.5%); however, the difference was not significant (P = 0.265). TC6 was safer than FEC-D, as the adverse events with docetaxel in the FEC-D regimen were similar to those with the TC6 regimen. Among patients with basal BC, the pCR rate was significantly higher with FEC-D (42.9%) than with TC6 (13.6%; P = 0.033). Among patients with triple-negative breast cancer (TNBC), the DFS and OS were significantly better with FEC-D than with TC6 (P = 0.016 and P = 0.034, respectively). CONCLUSION: TC6 was not as effective as FEC-D for treating HR-negative BC, as TC6 was not sufficient to treat TNBC, particularly the basal subtype. Our findings suggest that anthracyclines are better treatment options than taxanes for basal BC.

Clinical study on postoperative triple-negative breast cancer with Chinese medicine: Study protocol for an observational cohort trial.

BACKGROUND: Breast cancer (BC) poses a tremendous threat to the health of women worldwide, especially triple-negative breast cancers (TNBCs). Currently, the curative effect of traditional Chinese medicine (TCM) has been recognized in more and more people worldwide; however, the specific effect has not been systematically evaluated. The purpose of this cohort study is to evaluate the clinical effects of TCM syndrome differentiation on recurrence and metastasis rate, survival rate, and the quality of life in patients with TNBC. METHODS: This study is a multicenter observational cohort trial taking 2 years. A total of 620 patients will be allocated at a ratio of 1:1 to receive TCM or not. The primary outcomes are progression-free survival (PFS) and overall survival (OS), which are calculated at the end of the trial. Secondary outcomes include TCM symptoms, Karnofsky Performance Status (KPS), ECOG score, European Organization for Research and Treatment of Cancer (EORTC) Breast-Cancer-Specific Quality of Life Questionnaire (EORTC QLQ-BR23), as well as clinical indicators including tumor markers, immune function evaluation, chest computed tomography/magnetic resonance imaging, and abdominal B-ultrasound. Assessments will be performed at baseline and 3, 6, 9, 12, 16, and 20 weeks after observation. DISCUSSION: This will be the first clinical trial to evaluate the PFS and OS in TNBC patients receiving TCM, which may be used to assess the feasibility of a larger-scale clinical trial in the future, and formulate a standardized TCM treatment plan. STUDY REGISTRATION: ClinicalTrials.gov (NCT03332368).

De-escalating and escalating systemic therapy in triple negative breast cancer.

Triple negative breast cancer has the highest relapse risk of all the clinical subsets, although the escalation of chemotherapy has benefited this subset substantially over recent years. Systemic options are limited to chemotherapy, which makes meaningful de-escalation or escalation of therapy more challenging but possible. Observational cohorts suggest a less than 10% risk of relapse and minimal if any benefit of chemotherapy in very small (<1 cm), node-negative triple negative disease. In higher risk, particularly node-positive disease, anthracycline/taxane-based regimens remain standard. Neoadjuvant chemotherapy clearly de-escalates surgery, although there are insufficient data to give less than standard chemotherapy on the basis of response to neoadjuvant therapy. Efforts to meaningfully escalate therapy in high-risk disease have included incorporating platinums into Neoadjuvant therapy, with clear benefit in pCR but uncertain impact on relapse and survival at this time. Residual disease after neoadjuvant chemotherapy carries a particularly poor prognosis; a recent randomized trial of 6 months' capecitabine in this setting suggested a survival advantage to this approach in higher risk residual disease. While not validated at this time, future directions are likely to include biologic prognostication with tumor and immune variables, as well as targeted non-cytotoxic approaches leveraging the molecular heterogeneity of triple negative disease.

Irinotecan and capecitabine combination chemotherapy in a patient with triple-negative breast cancer relapsed after adjuvant chemotherapy with anthracycline and taxane.

The most effective regimen for taxane- and anthracycline-refractory triple-negative breast cancer (TNBC) has not yet been established. Capecitabine was approved by the US Food and Drug Administration for the treatment of advanced breast cancer and has shown efficacy in advanced breast cancer refractory to anthracyclines and taxanes. Irinotecan has synergism with 5-fluorouracil and shows efficacy in advanced breast cancer. Here we report on a patient with TNBC who relapsed with widespread bone and lung metastases shortly after adjuvant anthracycline followed by taxane chemotherapy. She achieved a metabolic complete response with irinotecan and capecitabine combination therapy and had 10 months' progression-free survival and 22 months' overall survival. She relapsed with and died of brain metastasis without any definite signs of progression of the lung and bone lesions she had had before the irinotecan and capecitabine combination therapy. To validate this favorable result, larger clinical trials are warranted in patients with metastatic or relapsed TNBC.

[A retrospective study of tegafur/uracil compared with cyclophosphamide, methotrexate, and fluorouracil as adjuvant chemotherapy in patients with node-negative, triple-negative breast cancer].

Japanese clinical trials of a tegafur/uracil(UFT)-based postoperative chemotherapy regimen compared with cyclophosphamide, methotrexate, and fluorouracil(CMF)treatment have shown that UFT is not inferior to CMF for the treatment of hormone receptor-positive breast cancer patients. However, the usefulness of UFT for hormone receptor-negative breast cancer, including the triple-negative subtype(hormone receptor-negative, human epidermal growth factor receptor 2 [HER2]-negative), is unknown. The aim of this retrospective study was to examine the effectiveness of postoperative, adjuvant UFT compared to CMF when these regimens were given to women with node-negative, triple-negative breast cancer. We analyzed 50 women with node-negative, triple-negative breast cancer who were treated with six cycles of CMF(n=33) or two years of UFT(n=17)after surgery between January 2000 and December 2010. Although no significant differences were observed in relapse-free survival or overall survival in all patients, subset analysis of tumors of larger size(t2), higher nuclear grade(NG3), and with positivity for lymphovascular invasion showed that UFT was inferior to CMF. These results encourage caution regarding the choice of adjuvant UFT for node-negative, triple-negative breast cancer.

BikDDA, a mutant of Bik with longer half-life expression protein, can be a novel therapeutic gene for triple-negative breast cancer.

Our previous studies showed that BikDD, a constitutively active mutant form of Bik, exhibited powerful antitumor effects in preclinical pancreatic, lung and breast cancer models. Howerver, the antitumor activity of BikDD in triple-negative breast cancer (TNBC) is unknown. Here we show that aberrant expression of p-ERK1/2 was a meaningful molecular phenotype in TNBC patients, and can be an obstacle for treatment because of the converse correlation with Bik. A novel mutant, BikDDA, in which Ser124 was changed to Alanine to block BikDD phosphorylation by p-ERK1/2 prevented subsequent ubiquitin-proteasome degradation. BikDDA showed a prolonged half-life and enhanced pro-apoptotic ability in TNBC cells compared with BikDD. Moreover, aberrant expression of p-ERK1/2 was associated with 5-fluorouracil resistance in breast cancer patients and BikDDA enhanced the therapeutic effects of 5-fluorouracil in vitro.

High Ki67 predicts unfavourable outcomes in early breast cancer patients with a clinically clear axilla who do not receive axillary dissection or axillary radiotherapy.

AIM: Axillary dissection is increasingly forgone in early breast cancer patients with a clinically negative axilla. The GRISO 053 randomised trial recruited 435 patients of age over 45 years, tumour ≤1.4 cm and clinically negative axilla, to assess the importance of axillary radiotherapy versus no axillary radiotherapy in patients not given axillary dissection. In the present study on a subgroup GRISO cases our aim was to assess the prognostic importance of tumour biological factors after more than 10 years of follow-up. METHODS: We retrospectively assessed biological factors in a subgroup of 285 GRISO cases (145 given axillary radiotherapy; 140 not given axillary radiotherapy) with complete biologic, therapeutic and follow-up information, using multivariable Cox proportional hazards regression modelling. RESULTS: Only 10-year cumulative incidence of distant metastasis was lower in the axillary radiotherapy (1%) than no axillary radiotherapy arm (7%) (p=0.037). Irrespective of study arm, hormone receptor positivity had significantly favourable effects on 10-year disease-free survival (DFS) and overall survival. human epidermal growth factor receptor 2 (HER2)-positive and triple-negative subtypes were associated with lower 10-year DFS (60% and 76%, respectively) than luminal A (96%) and B (91%) (p=0.001). Ten-year DFS for high (≥14%) Ki67 cancers was lower than for low Ki67 cancers (p=0.027); however, this effect was mainly confined to the no axillary radiotherapy arm. CONCLUDING STATEMENT: For patients with clinically node-negative small breast cancer not given axillary dissection, 10-year DFS is worsened by HER2 positivity, triple-negative phenotype and high Ki67. Axillary radiotherapy counteracts the negative prognostic effect of high Ki67 in patients not receiving axillary dissection.