Breast cancer chemotherapy

KMT2C is a potential biomarker of prognosis and chemotherapy sensitivity in breast cancer

PURPOSE

Epigenetic regulation plays critical roles in cancer progression, and high-frequency mutations or expression variations in epigenetic regulators have been frequently observed in tumorigenesis, serving as biomarkers and targets for cancer therapy. Here, we aimed to explore the function of epigenetic regulators in breast cancer.

METHODS

The mutational landscape of epigenetic regulators in breast cancer samples was investigated based on datasets from the Cancer Genome Atlas. The Kaplan-Meier method was used for survival analysis. RNA sequencing (RNA-seq) in MCF-7 cells transfected with control siRNA or KMT2C siRNA was performed. Quantitative reverse transcription-PCR and chromatin immunoprecipitation were used to validate the RNA-seq results.

RESULTS

Among the 450 epigenetic regulators, KMT2C was frequently mutated in breast cancer samples. The tumor mutational burden (TMB) was elevated in breast cancer samples with KMT2C mutations or low KMT2C mRNA levels compared to their counterparts with wild-type KMT2C or high KMT2C mRNA levels. Somatic mutation and low expression of KMT2C were independently correlated with the poor overall survival (OS) and disease-free survival (DFS) of the breast cancer samples, respectively. RNA-seq analysis combined with chromatin immunoprecipitation and qRT-PCR assays revealed that the depletion of KMT2C remarkably affected the expression of DNA damage repair-related genes. More importantly, the low expression of KMT2C was related to breast cancer cell sensitivity to chemotherapy and longer OS of breast cancer patients who underwent chemotherapy.

CONCLUSION

We conclude that KMT2C could serve as a potential biomarker of prognosis and chemotherapy sensitivity by affecting the DNA damage repair-related genes of breast cancer.

Crocin and Metformin suppress metastatic breast cancer progression via VEGF and MMP9 downregulations: in vitro and in vivo studies

Metastatic breast cancer remains a serious health concern and numerous investigations recommended medicinal plants as a complementary therapy. Crocin is one of the known anticancer bio-component. Recently, the inhibitory effect of metformin has been studied on the various aspects of cancer. However, no study reported their combination effects on metastatic breast cancer. In the present study, we have assessed their anti-metastatic effects on in vitro and in vivo breast cancer models. Using MTT assay, scratch, and adhesion tests, we have evaluated the cytotoxic, anti-invasive and anti-adhesion effects of crocin and metformin on 4T1 cell line, respectively. Their protective effects and MMP9 as well as VEGF protein expression levels (Western blotting) investigated in the 4T1 murine breast cancer model. Our results showed that both crocin and metformin reduced cell viability, delayed scratch healing and inhibited the cell adhesion, in vitro. While crocin alone restored the mice's weight reduction, crocin, metformin, and their combination significantly reduced the tumor volume size and enhanced animal survival rate in murine breast cancer model, responses that were associated with VEGF and MMP9 down-regulation. These findings suggest that a combination of crocin and metformin could serve as a novel therapeutic approach to enhance the effectiveness of metastatic breast cancer therapy.

SUMOylation Wrestles With the Occurrence and Development of Breast Cancer

Breast cancer has the highest incidence among cancers and is the most frequent cause of death in women worldwide. The detailed mechanism of the pathogenesis of breast cancer has not been fully elucidated, and there remains a lack of effective treatment methods for the disease. SUMOylation covalently conjugates a large amount of cellular proteins, and affects their cellular localization and biological activity to participate in numerous cellular processes. SUMOylation is an important process and imbalance of SUMOylation results in the progression of human diseases. Increasing evidence shows that numerous SUMOylated proteins are involved in the occurrence and development of breast cancer. This review summarizes a series of studies on protein SUMOylation in breast cancer in recent years. The study of SUMOylated proteins provides a comprehensive understanding of the pathophysiology of breast cancer and provides evolving therapeutic strategies for the treatment of breast cancer.

A DM1-doped porous gold nanoshell system for NIR accelerated redox-responsive release and triple modal imaging guided photothermal synergistic chemotherapy

Background

Although many treatments for breast cancer are available, poor tumour targeting limits the effectiveness of most approaches. Consequently, it is difficult to achieve satisfactory results with monotherapies. The lack of accurate diagnostic and monitoring methods also limit the benefits of cancer treatment. The aim of this study was to design a nanocarrier comprising porous gold nanoshells (PGNSs) co-decorated with methoxy polyethylene glycol (mPEG) and trastuzumab (Herceptin®, HER), a therapeutic monoclonal antibody that binds specifically to human epidermal receptor-2 (HER2)-overexpressing breast cancer cells. Furthermore, a derivative of the microtubule-targeting drug maytansine (DM1) was incorporated in the PGNSs.

Methods

Prepared PGNSs were coated with mPEG, DM1 and HER via electrostatic interactions and Au–S bonds to yield DM1-mPEG/HER-PGNSs. SK-BR-3 (high HER2 expression) and MCF-7 (low HER2) breast cancer cells were treated with DM1-mPEG/HER-PGNSs, and cytotoxicity was evaluated in terms of cell viability and apoptosis. The selective uptake of the coated PGNSs by cancer cells and subsequent intracellular accumulation were studied in vitro and in vivo using inductively coupled plasma mass spectrometry and fluorescence imaging. The multimodal imaging feasibility and synergistic chemo-photothermal therapeutic efficacy of the DM1-mPEG/HER-PGNSs were investigated in breast cancer tumour-bearing mice. The molecular mechanisms associated with the anti-tumour therapeutic use of the nanoparticles were also elucidated.

Result

The prepared DM1-mPEG/HER-PGNSs had a size of 78.6 nm and displayed excellent colloidal stability, photothermal conversion ability and redox-sensitive drug release. These DM1-mPEG/HER-PGNSs were taken up selectively by cancer cells in vitro and accumulated at tumour sites in vivo. Moreover, the DM1-mPEG/HER-PGNSs enhanced the performance of multimodal computed tomography (CT), photoacoustic (PA) and photothermal (PT) imaging and enabled chemo-thermal combination therapy. The therapeutic mechanism involved the induction of tumour cell apoptosis via the activation of tubulin, caspase-3 and the heat shock protein 70 pathway. M2 macrophage suppression and anti-metastatic functions were also observed.

Conclusion

The prepared DM1-mPEG/HER-PGNSs enabled nanodart-like tumour targeting, visibility by CT, PA and PT imaging in vivo and powerful tumour inhibition mediated by chemo-thermal combination therapy in vivo. In summary, these unique gold nanocarriers appear to have good potential as theranostic nanoagents that can serve both as a probe for enhanced multimodal imaging and as a novel targeted anti-tumour drug delivery system to achieve precision nanomedicine for cancers.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12951-021-00824-5.

Branched α-helical peptides enhanced antitumor efficacy and selectivity

Drug resistance to traditional chemotherapeutics is one of the main challenges in cancer treatment. Herein, cationic antimicrobial peptides (CAPs) were repurposed as anticancer agents to counter chemotherapy drug resistance. After a systematic study of de novo designed synthetic α-helical CAPs in various cell lines, the 4-arm branched peptide {[(LLKK)2]2κC}2 was found to exhibit better selectivity compared to its linear counterpart (LLKK)4, and was more effective than the 2-arm branched peptide [(LLKK)2]2κC. In particular, the 4-arm branched peptide could counter drug resistance and kill multiple drug resistant cells. Mechanism studies reveal that these α-helical peptides killed both the parent and resistant cancer cells based on the apoptotic pathway. The in vivo study in mice bearing breast tumors showed that branched peptides could be retained at the tumour sites after intratumoral injection and significantly reduced tumor growth while exhibiting minimal toxicity on main organs. These results indicate that the 4-arm branched peptide is a promising candidate for anticancer therapy.

Combination of using prodrug-modified cationic liposome nanocomplexes and a potentiating strategy via targeted co-delivery of gemcitabine and docetaxel for CD44-overexpressed triple negative breast cancer therapy

In this study, novel prodrug-modified cationic liposome nanocomplexes (Combo NCs) were reported for gemcitabine (GEM) and docetaxel (DTX) co-delivery. This nanoplatform exhibited multiple favorable characteristics, such as a 'green' fabrication with a one-step chemical reaction, appropriate size (∼200nm) and distribution (PDI<0.2), low zeta potential (-31.1mv), high drug-loading efficiency (9.3% GEM plus 3.1% DTX, wt%) and pH and enzymatic dual-stimulus-responsive release properties. Immunofluorescence and cellular uptake studies showed that Combo NCs efficiently targeted overexpressed CD44 in MDA-MB-231 carcinoma. In vitro studies revealed that Combo NCs played a critical role in the synergistic induction of cytotoxicity, apoptosis and inhibition of wound healing. Combo NCs were confirmed to exhibit great potency for increasing S phase arrest and remodeling the CDA and dCK balance by decreasing the mRNA expression of CDA down to 0.09-fold and increasing the mRNA expression of dCK by 1.36-fold, remarkably increasing the dCK/CDA ratio to 15.3-fold compared with the blank control. The biodistribution results obtained in vivo revealed an effective accumulation in tumor foci. All of these advantages of Combo NCs contributed to their remarkable anti-tumor efficacy without systemic toxicity as well as their apoptosis-enhancing and anti-proliferative capacities, as determined by TUNEL and Ki67 immunohistochemistry in vivo. Consequently, such a rationally contemplated co-delivery system demonstrated the promising potential of clinical applications for triple-negative breast cancer therapy.

STATE OF SIGNIFICANCE

The Combo NCs were innovatively applied for co-delivery of hydrophilic GEM and hydrophobic DTX. The ester bond linking and shielding effect of HA-GEM made the carriers achieve synchronous release properties, which was determined in in vitro release study. Due to the HA modification, the vectors own great potency for positive targeting to CD44 overexpressed triple-negative breast cancer cells MDA-MB-231. Cytotoxicity and apoptosis studies confirmed the targeting effect and synergism between two drugs. Interestingly, we found in cell cycle study, drug combinations (free combination or Combo NCs) didn't show a rise in G2M phase, which was significantly higher when treated DTX alone. We further discovered the role of DTX in combinations may involve in modulating GEM associated enzymes thus enhancing the efficacy of GEM. Consequently, this nanoplatform provided a novel solution for achieving targeted co-delivery and potentiating effect in cancer therapy.

Bovine herpesvirus 4-based vector delivering a hybrid rat/human HER-2 oncoantigen efficiently protects mice from autochthonous Her-2+ mammary cancer

The epidermal growth factor receptor 2 (HER-2) oncogene is a major target for the immunotherapy of breast cancer. Following up to the therapeutic success achieved with Her-2-targeting monoclonal antibodies, immune-prophylactic approaches directed against Her-2 have also been investigated taking into account, and trying to overcome, Her-2 self-tolerance. Perhaps due to safety (and efficacy) concerns, the least explored anti-Her-2 active immunization strategy so far has been the one relying on viral-vectored vaccine formulations. Taking advantage of the favorable properties of bovine herpesvirus 4 (BoHV-4) in terms of safety and ease of manipulation as well as its previously documented ability to transduce and confer immunogenicity to heterologous antigens, we tested the ability of different recombinant HER-2-BoHV-4 immunogens to 8break tolerance and elicit a protective, anti-mammary tumor antibody response in HER-2 transgenic BALB-neuT mice. All the tested constructs expressed the HER-2 transgenes at high levels and elicited significant cellular immune responses in BALB/c mice upon administration via either DNA vaccination or viral infection. In BALB-neuT mice, instead, only the viral construct expressing the membrane-bound chimeric form of Her-2 protein (BoHV-4-RHuT-gD) elicited a humoral immune response that was more intense and earlier-appearing than that induced by DNA vaccination. In keeping with this observation, two administrations of BoHV-4-RHuT-gD effectively protected BALB-neuT mice from tumor formation, with 50% of vaccinated animals tumor-free after 30 weeks from immunization compared to 100% of animals exhibiting at least one palpable tumor in the case of animals vaccinated with the other BoHV-4-HER-2 constructs.

The descriptive epidemiology of female breast cancer: an international comparison of screening, incidence, survival and mortality

BACKGROUND

This paper presents the latest international descriptive epidemiological data for invasive breast cancer amongst women, including incidence, survival and mortality, as well as information on mammographic screening programmes.

RESULTS

Almost 1.4 million women were diagnosed with breast cancer worldwide in 2008 and approximately 459,000 deaths were recorded. Incidence rates were much higher in more developed countries compared to less developed countries (71.7/100,000 and 29.3/100,000 respectively, adjusted to the World 2000 Standard Population) whereas the corresponding mortality rates were 17.1/100,000 and 11.8/100,000. Five-year relative survival estimates range from 12% in parts of Africa to almost 90% in the United States, Australia and Canada, with the differential linked to a combination of early detection, access to treatment services and cultural barriers. Observed improvements in breast cancer survival in more developed parts of the world over recent decades have been attributed to the introduction of population-based screening using mammography and the systemic use of adjuvant therapies.

CONCLUSION

The future worldwide breast cancer burden will be strongly influenced by large predicted rises in incidence throughout parts of Asia due to an increasingly "westernised" lifestyle. Efforts are underway to reduce the global disparities in survival for women with breast cancer using cost-effective interventions.

Clinical implications of cancer self-seeding

Most metastatic cancers are incurable--a fact that underscores the limitations of our existing paradigms for understanding metastasis. In this Review, we use breast cancer to explore many of the enigmas revealed by these existing paradigms. Traditionally, metastatic models describe metastasis as a unidirectional process, whereby cancer cells leave a primary tumor and unidirectionally seed metastasis in regional lymph nodes or distant sites. By contrast, recent data indicate that metastasis is a multidirectional process whereby cancer cells can seed distant sites as well as the primary tumor itself. This later process, known as 'self-seeding,' has been validated in diverse experimental models. Here, we show that the self-seeding model may answer many of the mysteries inherent to cancer metastasis. Indeed, reframing our understanding of metastasis within the self-seeding model offers new opportunities for prevention and cure of metastatic cancer.

Increased expression of hyaluronic acid binding protein 1 is correlated with poor prognosis in patients with breast cancer

BACKGROUND AND OBJECTIVES

Hyaluronic acid binding protein 1 (HABP1), a family of proteins interacting with hyaluronan (HA), had been associated with cell adhesion and tumor invasion. The aim of this study was to investigate the correlation between clinicopathologic factors and patient survival time with the expression of HABP1 in breast cancer patients.

METHODS

Expression of HABP1 mRNA and protein were detected with real-time quantitative PCR and immunohistochemical staining in 63 breast cancer and non-cancerous matched tissues.

RESULTS

The mRNA expression level of HABP1 was unrelated to the patient's age, tumor size, histological grade, TNM stage. However, it proved to be positively related to axillary nodes metastasis (P = 0.008). Furthermore, it was shown that the survival rate of patients with low HABP1 expression was significantly higher than that of patients with high HABP1 expression (P = 0.025). Multivariate analysis revealed that HABP1 mRNA expression level was a significant factor for predicting prognosis (P = 0.022). The immunohistochemistry results showed that the expression level of HABP1 in breast cancer cells was higher than that in normal breast cells.

CONCLUSION

HABP1 might be an independent predictive factor for breast cancer prognosis and up-regulation of HABP1 might play an important role in the metastasis of breast cancer.

Prodigiosin down-regulates survivin to facilitate paclitaxel sensitization in human breast carcinoma cell lines

Prodigiosin is a bacterial metabolite with potent anticancer activity, which is attributed to its proapoptotic effect selectively active in malignant cells. Still, the molecular mechanisms whereby prodigiosin induces apoptosis remain largely unknown. In particular, the role of survivin, a vital inhibitor of apoptosis, in prodigiosin-induced apoptosis has never been addressed before and hence was the primary goal of this study. Our results showed that prodigiosin dose-dependently induced down-regulation of survivin in multiple breast carcinoma cell lines, including MCF-7, T-47D and MDA-MB-231. This down-regulation is mainly regulated at the level of transcription, as prodigiosin reduced the levels of both survivin mRNA and survivin promoter activity but failed to rescue survivin expression when proteasome-mediated degradation is abolished. Importantly, overexpression of survivin rendered cells more resistant to prodigiosin, indicating an essential role of survivin down-regulation in prodigiosin-induced apoptosis. In addition, we found that prodigiosin synergistically enhanced cell death induced by paclitaxel, a chemotherapy drug known to up-regulate survivin that in turn confers its own resistance. This paclitaxel sensitization effect of prodigiosin is ascribed to the lowering of survivin expression, because prodigiosin was shown to counteract survivin induction by paclitaxel and, notably, the sensitization effect was severely abrogated in cells that overexpress survivin. Taken together, our results argue that down-regulation of survivin is an integral component mediating prodigiosin-induced apoptosis in human breast cancer cells, and further suggest the potential of prodigiosin to sensitize anticancer drugs, including paclitaxel, in the treatment of breast cancer.