Regulation of AMPK-related glycolipid metabolism imbalances redox homeostasis and inhibits anchorage independent growth in human breast cancer cells

Breast cancer is one of the most lethal tumors in the world, among which 15% are triple-negative breast cancers (TNBCs) with higher metastasis and lower survival rate. Anoikis resistance is a key process during tumor metastasis, which is usually accompanied with metabolism reprogram. In this study, we established an anchorage independent growth model for MDA-MB-231 cells and investigated the changes in metabolism and redox homeostasis. Results showed that during detached-growth, MDA-MB-231 cells tend to generate ATP through fatty acid oxidation (FAO), instead of glycolysis. Amount of glucose was used for pentose phosphate pathway (PPP) to keep redox balance. Moreover, we discovered that a synthesized flavonoid derivative GL-V9, exhibited a potent inhibitory effect on the anchorage independent growth of TNBCs in vitro and anti-metastasis effect in vivo. In terms of the mechanism, GL-V9 could promote the expression and activity of AMPK, leading to the decrease of G6PD and the increase of p-ACC. Thus, the level of PPP was suppressed, whereas FAO was highly enhanced. The reprogram of glycolipid metabolism destroyed the redox balance ultimately and induced cell death. This paper indicated a novel regulating mechanism of redox homeostasis involving with glycolipid metabolism, and provided a potential candidate for the anti-metastatic therapy of TNBCs.

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Instead of glycolysis, FAO is the dominant way for ATP generation in anchorage independent growth.

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Glucose in cells detached from EMC is used for PPP to resist the ROS form OXPHOS.

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GL-V9 inhibits anchorage independent growth via imbalancing the redox homeostasis.

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AMPK is the critical regulator in GL-V9-induced glycolipid metabolism reprogram.

The value of platinum agents as neoadjuvant chemotherapy in triple-negative breast cancers: a systematic review and meta-analysis

Platinum agents such as cisplatin and carboplatin are DNA-damaging agents with activity in breast cancer (BC), particularly in the triple negative (TN) subgroup. The utility of platinum agents, in addition to standard neoadjuvant chemotherapy (NAC), is controversial. To assess the activity of platinum agents in patients with TNBC treated with NAC, we performed a systematic review and meta-analysis of all published studies. A search of PubMed, EMBASE, the Web of Science, SCOPUS, and the Cochrane Central Register of Controlled Trials was performed to identify studies that investigated platinum-based NAC in patients with TNBC. Random effect models were adopted to estimate the summary risk ratio (RR), and the publication bias was evaluated using a funnel plot and Egger's regression asymmetry test. The primary endpoints were the pooled rate of the pathologic complete response (pCR) and the RR to obtain a pCR in patients treated versus not treated with NAC containing platinum agents. 28 studies were included (six randomized controlled trials and 22 retrospective or prospective studies) for a total of 1,598 TNBC patients. Overall, the pooled rate of pCR in patients treated with platinum-based NAC was 45 %. In randomized trials, NAC containing cisplatin or carboplatin significantly increased the rate of pCR compared with nonplatinum agents (RR = 1.45, 95 % CI 1.25-1.68; P < 0.0001). Compared with non-TN, TNBCs were associated with a threefold increase in the pCR rate when treated with platinum-based NAC (RR 3.32, 95 % CI 2.39-4.61; P < 0.0001). In conclusion, pCR rates increase significantly with the addition of cisplatin or carboplatin in TNBC compared with NAC containing no platinum drugs. TN status is a predictor of benefit from platinum-based NAC.

Triple-negative breast cancer and the need for new therapeutic targets

Triple-negative breast cancers (TNBCs) are a diverse and heterogeneous group of tumors that by definition lack estrogen and progesterone receptors and amplification of the HER2 gene. The majority of the tumors classified as TNBCs are highly malignant, and only a subgroup responds to conventional chemotherapy with a favorable prognosis. Results from decades of research have identified important molecular characteristics that can subdivide this group of breast cancers further. High-throughput molecular analyses including sequencing, pathway analyses, and integrated analyses of alterations at the genomic and transcriptomic levels have improved our understanding of the molecular alterations involved in tumor development and progression. How this knowledge should be used for rational selection of therapy is a challenging task and the subject of numerous ongoing research programs. This review summarizes the current knowledge on the clinical characteristics and molecular alterations of TNBCs. Currently used conventional therapeutic strategies and targeted therapy studies are discussed, with references to recently published results on the molecular characterization of TNBCs.

Impact of breast cancer subtypes and treatment on survival: an analysis spanning two decades

BACKGROUND

We investigated the impact of breast cancer molecular subtypes and treatment on survival in a cohort of medically insured women followed for more than 20 years.

METHODS

We examined 934 female members of an integrated health care delivery system newly diagnosed with invasive breast cancer between 1988 and 1995 and followed them through 2008. Tumors were classified into four molecular subtypes on the basis of their expression profile: luminal A; luminal B; basal-like; and HER2-enriched. We followed women from the surgery date to death, health plan disenrollment, or study's end. HR and 95% confidence intervals (CI) were fit using Cox proportional hazards models adjusting for cancer treatments and tumor characteristics.

RESULTS

A total of 223 (23.9%) women died because of breast cancer during the 21-year study period. Compared with women with luminal A tumors, women with HER2-enriched (HR 2.56, 95% CI 1.53-4.29) and luminal B tumors (HR 1.96, 95% CI: 1.08-3.54) had roughly a two-fold increased adjusted risk of breast cancer mortality. In addition, the survival curves suggest that risk of late mortality persists in women with luminal A tumors.

CONCLUSION

Among women with health care coverage, molecular subtypes were important predictors of breast cancer mortality. Women with HER2-enriched tumors and luminal B subtypes had the poorest survival despite adjusting for important covariates.

IMPACT

In a cohort followed for more than 20 years, women with HER2-enriched tumors had worse survival, but interestingly, the survival curve for women with luminal A tumors continued to steadily decline after 10 years of follow-up.

A phase 2 study of sequential neoadjuvant chemotherapy with gemcitabine and doxorubicin followed by gemcitabine and cisplatin in patients with large or locally advanced operable breast cancer: results from long-term follow-up

BACKGROUND

Neoadjuvant chemotherapy (NACT) is being increasingly used for patients with large-size operable breast cancer. This phase 2 study of sequential NACT with gemcitabine and doxorubicin (Gem + Dox) followed by gemcitabine and cisplatin (Gem + Cis) was conducted in women with large or locally advanced breast cancer. The objectives were to evaluate the pathological complete response (pCR) rate, toxicity, pathological and genetic markers predicting response, the proportion of patients undergoing breast conservation surgery, progression-free survival (PFS) and overall survival (OS) after 5 years, and time to treatment failure (TtTF). In this manuscript, we report the long-term OS, PFS, and TtTF results.

METHODS

Female patients aged at least 18 years with large T2 (at least 3 cm) or locally advanced (T3, T4, or N2) breast carcinoma were included. Treatment consisted of 4 cycles of Gem + Dox (gemcitabine 1,200 mg/m(2) on days 1 and 8 plus doxorubicin 60 mg/m(2) on day 1 of each 21-day cycle), followed by 4 cycles of Gem + Cis (gemcitabine 1,000 mg/m(2) on days 1 and 8 plus cisplatin 70 mg/m(2) on day 1 of each 21-day cycle), and then surgery.

RESULTS

Sixty-five patients were enrolled. The pCR rate was 20%. The 5-year OS probability was 71% (95% CI 56-82%), and the 4-year PFS and TtTF probabilities were 63% (95% CI 48-74%) and 45% (95% CI 32-57%), respectively.

CONCLUSIONS

NACT with Gem + Dox followed by Gem + Cis was efficacious in patients with operable breast cancer.

Basal phenotype breast cancer: implications for treatment and prognosis

Breast cancer is the most common malignancy in females. The origins and biology of breast carcinomas remain unclear. Cellular and molecular heterogeneity results in different distinct groups of tumors with different clinical behavior and prognosis. Gene expression profiling has delineated five molecular subtypes based on similarities in gene expression: luminal A, luminal B, HER2 overexpressing, normal-like and basal-like. Basal-like breast cancer (BLBC) lacks estrogen receptor, progesterone receptor and HER2 expression, and comprises myoepithelial cells. Specific features include high proliferative rate, rapid growth, early recurrence and decreased overall survival. BLBC is associated with ductal carcinoma in situ, BRCA1 mutation, brain and lung metastasis, and negative axillary lymph nodes. Currently, chemotherapy is the only therapeutic choice, but demonstrates poor outcomes. There is an overlap in definition between triple-negative breast cancer and BLBC due to the triple-negative profile of BLBC. Despite the molecular and clinical similarities, the two subtypes respond differently to neoadjuvant therapy. Although particular morphologic, genetic and clinical features of BLBC have been identified, a variety of definitions among studies accounts for the contradictory results reported. In this article the molecular morphological and histopathological profile, the clinical behavior and the therapeutic options of BLBC are presented, with emphasis on the discordant findings among studies.

Preoperative concurrent paclitaxel-radiation in locally advanced breast cancer: pathologic response correlates with five-year overall survival

We have previously demonstrated high pathologic response rates after neoadjuvant concurrent chemoradiation in patients with locally advanced breast cancer (LABC). We now report disease-free survival (DFS) and overall survival (OS) in the context of pathologic response. 105 LABC patients (White 46%, Non-White 54%) were treated with paclitaxel (30 mg/m² intravenously twice a week) for 10-12 weeks. Daily radiotherapy was delivered to breast, axillary, and supraclavicular lymph nodes during weeks 2-7 of paclitaxel treatment, at 1.8 Gy per fraction to a total dose of 45 Gy with a tumor boost of 14 Gy at 2 Gy/fraction. Pathological complete response (pCR) was defined as the absence of invasive cancer in breast and lymph nodes and pathological partial response (pPR) as the persistence of <10 microscopic foci of invasive carcinoma in breast or lymph nodes. Pathologic response (pCR and pPR) after neoadjuvant chemoradiation was achieved in 36/105 patients (34%) and was associated with significantly better DFS and OS. Pathological responders had a lower risk of recurrence or death (HR = 0.35, P = 0.01) and a longer OS (HR = 4.27, P = 0.01) compared with non-responders. Median DFS and OS were 57 and 84 months for non-responders, respectively, and have not yet been reached for responders. Importantly, pathologic response was achieved in 54% of patients with HR negative tumors (26/48). In conclusion, pathologic response to concurrent paclitaxel-radiation translated into superior DFS and OS. Half of the patients with HR negative tumors achieved a pathologic response.

Neoadjuvant therapy for locally advanced breast cancer: Focus on chemotherapy and biological targeted treatments' armamentarium

Despite progress achieved in diagnosis and therapy in recent years, locally advanced breast cancer (LABC) remains a major clinical issue. Biological characteristics and clinical behavior varies widely, ranging from indolent to locally aggressive or generalized disease. In depth knowledge of biology of cancer progression and cancer could lead to the identification of tumor characteristics associated with outcome. Neoadjuvant chemotherapy (NCT) integrated into a multimodality program is nowadays the established treatment in LABC. Although our efforts in this research task are ongoing, of special clinical interest is the integration of anti-HER2 and other biological therapies, as anti-angiogenesis targeted treatments, that may further improve the long term control of LABC. Clinical management of LABC could be modified based on molecular biology and an approach tailored to each patient will optimize therapy.