Vascular proliferation is increased in basal-like breast cancer

Hypoxia induced responses are reflected in the stromal proteome of breast cancer

Cancers are often associated with hypoxia and metabolic reprogramming, resulting in enhanced tumor progression. Here, we aim to study breast cancer hypoxia responses, focusing on secreted proteins from low-grade (luminal-like) and high-grade (basal-like) cell lines before and after hypoxia. We examine the overlap between proteomics data from secretome analysis and laser microdissected human breast cancer stroma, and we identify a 33-protein stromal-based hypoxia profile (33P) capturing differences between luminal-like and basal-like tumors. The 33P signature is associated with metabolic differences and other adaptations following hypoxia. We observe that mRNA values for 33P predict patient survival independently of molecular subtypes and basic prognostic factors, also among low-grade luminal-like tumors. We find a significant prognostic interaction between 33P and radiation therapy.

Vessel size as a marker of survival in estrogen receptor positive breast cancer

PURPOSE

Angiogenesis is crucial for tumor growth and is one of the hallmarks of cancer. In this study, we analyzed microvessel density, vessel median size, and perivascular a-SMA expression as prognostic biomarkers in breast cancer.

METHODS

Dual IHC staining was performed where alpha-SMA antibodies were used together with antibodies against the endothelial cell marker CD34. Digital images of stainings were analyzed to extract quantitative data on vessel density, vessel size, and perivascular alpha-SMA status.

RESULTS

The analyses in the discovery cohort (n = 108) revealed a statistically significant relationship between large vessel size and shorter disease-specific survival (p = 0.007, log-rank test; p = 0.01, HR 3.1; 95% CI 1.3-7.4, Cox-regression analyses). Subset analyses indicated that the survival association of vessel size was strengthened in ER + breast cancer. To consolidate these findings, additional analyses were performed on a validation cohort (n = 267) where an association between large vessel size and reduced survival was also detected in ER + breast cancer (p = 0.016, log-rank test; p = 0.02; HR 2.3, 95% CI 1.1-4.7, Cox-regression analyses).

CONCLUSION

Alpha-SMA/CD34 dual-IHC staining revealed breast cancer heterogeneity regarding vessel size, vessel density, and perivascular a-SMA status. Large vessel size was linked to shorter survival in ER + breast cancer.

Adverse events of bevacizumab for triple negative breast cancer and HER-2 negative metastatic breast cancer: A meta-analysis

Background: Triple-negative breast cancer (TNBC) and HER-2 negative metastatic breast cancer (HER-2 negative MBC) are intractable to various treatment schemes. Bevacizumab as a novel anti-VEGF drug, its safety for these two high-risk breast cancers remains controversial. Therefore, we conducted this meta-analysis to assess the safety of Bevacizumab for TNBC and HER-2 negative MBC. Methods: We searched Medline, Embase, Web of science and Cochrane databases updated to 1 Oct 2022 for relevant randomized controlled trials (RCTs). In all, 18 RCTs articles with 12,664 female patients were included. We used any grade Adverse Events (AEs) and grade ≥3 AEs to assess the AEs of Bevacizumab. Results: Our study demonstrated that the application of Bevacizumab was associated with increased incidence of grade ≥3 AEs (RR = 1.37, 95% CI 1.30-1.45, Rate: 52.59% vs. 41.32%). Any grade AEs (RR = 1.06, 95% CI 1.04-1.08, Rate: 64.55% vs. 70.59%) did not show a significant statistical difference in both overall results and among the subgroups. In subgroup analysis, HER-2 negative MBC (RR = 1.57, 95% CI 1.41-1.75, Rate: 39.49% vs. 25.6%), dosage over 15 mg/3w (RR = 1.44, 95% CI 1.07-1.92, Rate: 28.67% vs. 19.93%) and endocrine therapy (ET) (RR = 2.32, 95% CI 1.73-3.12, Rate: 31.17% vs. 13.42%) were associated with higher risk of grade ≥3 AEs. Of all graded ≥3 AEs, proteinuria (RR = 9.22, 95%CI 4.49-18.93, Rate: 4.22% vs. 0.38%), mucosal inflammation (RR = 8.12, 95%CI 2.46-26.77, Rate: 3.49% vs. 0.43%), palmar-plantar erythrodysesthesia syndrome (RR = 6.95, 95%CI 2.47-19.57, Rate: 6.01% vs. 0.87%), increased Alanine aminotransferase (ALT) (RR = 6.95, 95%CI 1.59-30.38, Rate: 3.13% vs. 0.24%) and hypertension (RR = 4.94, 95%CI 3.84-6.35, Rate: 9.44% vs. 2.02%) had the top five risk ratios. Conclusion: The addition of Bevacizumab for TNBC and HER-2 negative MBC patients showed an increased incidence of AEs especially for grade ≥3 AEs. The risk of developing different AEs varies mostly dependent on the type of breast cancer and combined therapy. Systematic Review Registration: [https://www.crd.york.ac.uk/PROSPERO/#recordDetails], identifier [CRD42022354743].

A deep matrix factorization framework for identifying underlying tissue-specific patterns of DCE-MRI: applications for molecular subtype classification in breast cancer

Objective.Breast cancer is heterogeneous in that different angiogenesis and blood flow characteristics could be present within a tumor. The pixel kinetics of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) can assume several distinct signal patterns related to specific tissue characteristics. Identification of the latent, tissue-specific dynamic patterns of intratumor heterogeneity can shed light on the biological mechanisms underlying the heterogeneity of tumors.Approach.To mine this information, we propose a deep matrix factorization-based dynamic decomposition (DMFDE) model specifically designed according to DCE-MRI characteristics. The time-series imaging data were decomposed into tissue-specific dynamic patterns and their corresponding proportion maps. The image pixel matrix and the reference matrix of population-level kinetics obtained by clustering the dynamic signals were used as the inputs. Two multilayer neural network branches were designed to collaboratively project the input matrix into a latent dynamic pattern and a dynamic proportion matrix, which was justified using simulated data. Clinical implications of DMFDE were assessed by radiomics analysis of proportion maps obtained from the tumor/parenchyma region for classifying the luminal A subtype.Main results.The decomposition performance of DMFDE was evaluated by the root mean square error and was shown to be better than that of the conventional convex analysis of mixtures (CAM) method. The predictive model withK = 3, 4, and 5 dynamic proportion maps generated AUC values of 0.780, 0.786 and 0.790, respectively, in distinguishing between luminal A and nonluminal A tumors, which are better than the CAM method (AUC = 0.726). The combination of statistical features from images with different proportion maps has the highest prediction value (AUC = 0.813), which is significantly higher than that based on CAM.Conclusion.This proposed method identified the latent dynamic patterns associated with different molecular subtypes, and radiomics analysis based on the pixel compositions of the uncovered dynamic patterns was able to determine molecular subtypes of breast cancer.

Antiangiogenic therapy reverses the immunosuppressive breast cancer microenvironment

Tumor angiogenesis induces local hypoxia and recruits immunosuppressive cells, whereas hypoxia subsequently promotes tumor angiogenesis. Immunotherapy efficacy depends on the accumulation and activity of tumor-infiltrating immune cells (TIICs). Antangiogenic therapy could improve local perfusion, relieve tumor microenvironment (TME) hypoxia, and reverse the immunosuppressive state. Combining antiangiogenic therapy with immunotherapy might represent a promising option for the treatment of breast cancer. This article discusses the immunosuppressive characteristics of the breast cancer TME and outlines the interaction between the tumor vasculature and the immune system. Combining antiangiogenic therapy with immunotherapy could interrupt abnormal tumor vasculature-immunosuppression crosstalk, increase effector immune cell infiltration, improve immunotherapy effectiveness, and reduce the risk of immune-related adverse events. In addition, we summarize the preclinical research and ongoing clinical research related to the combination of antiangiogenic therapy with immunotherapy, discuss the underlying mechanisms, and provide a view for future developments. The combination of antiangiogenic therapy and immunotherapy could be a potential therapeutic strategy for treatment of breast cancer to promote tumor vasculature normalization and increase the efficiency of immunotherapy.

Molecular Profiles of Brain Metastases: A Focus on Heterogeneity

Simple Summary

Precision cancer medicine depends on the characterization of tumor samples, usually by a single-tumor biopsy, to administer an optimal therapeutic. However, primary tumors and their metastases are often heterogeneous. A metastatic lesion may harbor a completely different genetic makeup to that of its parent tumor, and a single tumor sampling may be ineffective in selecting the most efficient therapy. Brain metastases, due to their low availability and specific microenvironment, pose a particular challenge for precision medicine. In this review, we highlight the genetic landscape of brain metastases, with a particular focus on their heterogeneity. To illustrate this problem, we present phenotypic alterations in brain metastases originating from lung cancer, breast cancer, and melanoma. This article may help clinicians better understand alterations in brain metastases and the relevance of their heterogeneity.

Abstract

Brain metastasis is a common and devastating clinical entity. Intratumor heterogeneity in brain metastases poses a crucial challenge to precision medicine. However, advances in next-generation sequencing, new insight into the pathophysiology of driver mutations, and the creation of novel tumor models have allowed us to gain better insight into the genetic landscapes of brain metastases, their temporal evolution, and their response to various treatments. A plethora of genomic studies have identified the heterogeneous clonal landscape of tumors and, at the same time, introduced potential targets for precision medicine. As an example, we present phenotypic alterations in brain metastases originating from three malignancies with the highest brain metastasis frequency: lung cancer, breast cancer, and melanoma. We discuss the barriers to precision medicine, tumor heterogeneity, the significance of blood-based biomarkers in tracking clonal evolution, the phylogenetic relationship between primary and metastatic tumors, blood–brain barrier heterogeneity, and limitations to ongoing research.

Baseline microvessel density predicts response to neoadjuvant bevacizumab treatment of locally advanced breast cancer

A subset of breast cancer patients benefits from preoperative bevacizumab and chemotherapy, but validated predictive biomarkers are lacking. Here, we aimed to evaluate tissue-based angiogenesis markers for potential predictive value regarding response to neoadjuvant bevacizumab treatment in breast cancer. In this randomized 1:1 phase II clinical trial, 132 patients with large or locally advanced HER2-negative tumors received chemotherapy ± bevacizumab. Dual Factor VIII/Ki-67 immunohistochemical staining was performed on core needle biopsies at baseline and week 12. Microvessel density (MVD), proliferative microvessel density (pMVD; Factor VIII/Ki-67 co-expression), glomeruloid microvascular proliferation (GMP), and a gene expression angiogenesis signature score, were studied in relation to pathologic complete response (pCR), clinico-pathologic features and intrinsic molecular subtype. We found that high baseline MVD (by median) significantly predicted pCR in the bevacizumab-arm (odds ratio 4.9, P = 0.012). High pMVD, presence of GMP, and the angiogenesis signature score did not predict pCR, but were associated with basal-like (P ≤ 0.009) and triple negative phenotypes (P ≤ 0.041). pMVD and GMP did also associate with high-grade tumors (P ≤ 0.048). To conclude, high baseline MVD significantly predicted response to bevacizumab treatment. In contrast, pMVD, GMP, and the angiogenesis signature score, did not predict response, but associated with aggressive tumor features, including basal-like and triple-negative phenotypes.

Dynamic and subtype-specific interactions between tumour burden and prognosis in breast cancer

We investigated the relationship between the prognostic importance of anatomic tumour burden and subtypes of breast cancer using data from the Korean Breast Cancer Registry Database. In HR+/HER2+ and HR−/HER2−tumours, an increase in T stage profoundly increased the hazard of death, while the presence of lymph node metastasis was more important in HR+/HER2+ and HR−/HER2+ tumours among 131,178 patients with stage I–III breast cancer. The patterns of increasing mortality risk and tumour growth (per centimetre) and metastatic nodes (per node) were examined in 67,038 patients with a tumour diameter ≤ 7 cm and < 8 metastatic nodes. HR+/HER2− and HR−/HER2− tumours showed a persistent increase in mortality risk with an increase in tumour diameter, while the effect was modest in HER2+ tumours. Conversely, an increased number of metastatic nodes was accompanied by a persistently increased risk in HR−/HER2+ tumours, while the effect was minimal for HR−/HER2− tumours with > 3 or 4 nodes. The interactions between the prognostic significance of anatomic tumour burden and subtypes were significant. The prognostic relevance of the anatomic tumour burden was non-linear and highly dependent on the subtypes of breast cancer.

Heterogeneity and vascular permeability of breast cancer brain metastases

Improvements in the diagnosis and treatment of systemic breast cancer have led to a prolongation in patient survival. Unfortunately, these advances are also associated with an increased incidence of brain metastases (BM), with the result that many patients succumb due to BM treatment failure. Intracranial delivery of many chemotherapeutic agents and other therapeutics is hindered by the presence of an impermeable blood-brain barrier (BBB) designed to protect the brain from harmful substances. The formation of BM compromises the integrity of the BBB, resulting in a highly heterogeneous blood-tumor barrier (BTB) with varying degrees of vascular permeability. Here, we discuss how blood vessels play an important role in the formation of brain micrometastases as well as in the transformation from poorly permeable BM to highly permeable BM. We then review the role of BTB vascular permeability in the diagnostics and the choice of treatment regimens for breast cancer brain metastases (BCBM) and discuss whether the vasculature of primary breast cancers can serve as a biomarker for BM. Specifically, we examine the association between the vascular permeability of BCBM and their accumulation of large molecules such as antibodies, which remains largely unexplored.

Molecular subtypes and precision treatment of triple-negative breast cancer

Triple-negative breast cancer (TNBC) is the most aggressive breast cancer subtype. Despite the progress made in precision treatment of cancer patients, targeted treatment is still at its early stage in TNBC, and chemotherapy remains the standard treatment. With the advances in next generation sequencing technology, genomic and transcriptomic analyses have provided deeper insight into the inter-tumoral heterogeneity of TNBC. Much effort has been made to classify TNBCs into different molecular subtypes according to genetic aberrations and expression signatures and to uncover novel treatment targets. In this review, we summarized the current knowledge regarding the molecular classification of TNBC and explore the future paradigm for using molecular classification to guide the development of precision treatment and clinical practice.

Stathmin expression associates with vascular and immune responses in aggressive breast cancer subgroups

Studies indicate that stathmin expression associates with PI3K activation in breast cancer, suggesting stathmin as a marker for targetable patient subgroups. Here we assessed stathmin in relation to tumour proliferation, vascular and immune responses, BRCA1 germline status, basal-like differentiation, clinico-pathologic features, and survival. Immunohistochemical staining was performed on breast cancers from two series (cohort 1, n = 187; cohort 2, n = 198), and mass spectrometry data from 24 cases and 12 breast cancer cell lines was examined for proteomic profiles. Open databases were also explored (TCGA, METABRIC, Oslo2 Landscape cohort, Cancer Cell Line Encyclopedia). High stathmin expression associated with tumour proliferation, p53 status, basal-like differentiation, BRCA1 genotype, and high-grade histology. These patterns were confirmed using mRNA data. Stathmin mRNA further associated with tumour angiogenesis, immune responses and reduced survival. By logistic regression, stathmin protein independently predicted a BRCA1 genotype (OR 10.0, p = 0.015) among ER negative tumours. Cell line analysis (Connectivity Map) implied PI3K inhibition in tumours with high stathmin. Altogether, our findings indicate that stathmin might be involved in the regulation of tumour angiogenesis and immune responses in breast cancer, in addition to tumour proliferation. Cell data point to potential effects of PI3K inhibition in tumours with high stathmin expression.

Evaluation of Vascular Proliferation in Molecular Subtypes of Breast Cancer

BACKGROUND

Angiogenesis plays a pivotal role in tumor development. Although microvessel density (MVD) is the most common method used for evaluation of angiogenesis, it has several limitations. Our aim was to evaluate MVD and microvessel proliferation (MVP) in a series of invasive breast carcinomas and analyze whether angiogenesis is influenced by the molecular phenotype of each tumor.

MATERIALS AND METHODS

We examined vascular proliferation using double immunohistochemistry (CD34/Ki67) in a series of 54 invasive breast carcinomas and compared the results with standard MVD, molecular subtypes and other classical parameters.

RESULTS

Increased MVD and MVP values were recorded in basal-like subtype, but only the MVP value reached significance among this group of patients (p=0.0001). For all cases combined, increased MVP was significantly correlated with negative estrogen receptor (ER) status (p=0.010) and higher histological grade (p=0.002).

CONCLUSION

MVP more accurately reflects the state of angiogenesis in breast cancer, compared with standard MVD. Vascular proliferation was associated with aggressive tumor features, indicating its contribution to tumor progression. The strong association between vascular proliferation and basal-like tumors suggests that this marker can be used for stratification of patients who might benefit from therapies targeting angiogenesis.

Microvascular proliferation is associated with aggressive tumour features and reduced survival in lung adenocarcinoma

Despite new treatment options in lung cancer, there is still a need for better biomarkers to assist in therapy decisions. Angiogenesis has been associated with tumour growth and dissemination, and the vascular proliferation index (VPI) is a valuable prognostic marker in other tumours. Nestin, a marker of immature endothelium, was previously applied in combination with Ki67 for proliferating endothelium as a novel marker (Nestin‐Ki67) of ongoing angiogenesis. Here, the prevalence and prognostic impact of vascular proliferation on lung cancer‐specific survival (LCSS) in lung adenocarcinomas was studied. Selected tumour slides from a cohort of 210 patients treated surgically for adenocarcinoma at Haukeland University Hospital (Norway) from 1993 to 2010 were stained for Nestin‐Ki67. VPI, the ratio between the density of proliferating vessels and the overall microvessel density were used, and the cut‐off value was set at 4.4% (upper quartile). High VPI was associated with the presence of blood vessel invasion (p = 0.007) and tumour necrosis (p = 0.007). Further, high VPI was significantly associated with reduced LCSS (p = 0.020). By multivariate analysis, VPI remained an independent prognostic factor for reduced LCSS (HR 1.7; 95% CI 1.04–2.68; p = 0.033) when adjusted for other prognostic clinico‐pathological features. In conclusion, microvessel proliferation assessed using the VPI was associated with aggressive tumour features such as blood vessel invasion and tumour necrosis and, independently, decreased LCSS. This marker should be further explored in separate cohorts, and in trials of anti‐angiogenesis therapy.

Activation of GPER suppresses migration and angiogenesis of triple negative breast cancer via inhibition of NF-κB/IL-6 signals

Triple-negative breast cancer (TNBC) is characterized by high vascularity and frequent metastasis. Here, we found that activation of G protein-coupled estrogen receptor (GPER) by its specific agonist G-1 can significantly inhibit interleukin 6 (IL-6) and vascular endothelial growth factor A (VEGF-A). TNBC tissue microarrays from 100 TNBC patients revealed GPER is negatively associated with IL-6 levels and higher grade and stage. Activation of GPER or anti-IL-6 antibody can inhibit both in vitro tube formation of human umbilical vein endothelial cells (HUVECs) and migration of TNBC cells. While recombinant IL-6 supplementary can significantly reverse the inhibitory effects of G-1, suggesting the essential role of IL-6 in G-1 induced suppression of angiogenesis and invasiveness of TNBC cells. G-1 treatment decreased the phosphorylation, nuclear localization, transcriptional activities of NF-κB and suppressed its binding with IL-6 promoter. BAY11-7028, the inhibitor of NF-κB, can mimic the effect of G-1 to suppression of IL-6 and VEGF-A. While over expression of p65 can attenuate the inhibitory effects of G-1 on IL-6 and VEGF expression. The suppression of IL-6 by G-1 can further inhibit HIF-1α and STAT3 signals in TNBC cells by inhibition their expression, phosphorylation and/or nuclear localization. Moreover, G-1 also inhibited the in vivo NF-κB/IL-6 signals and angiogenesis and metastasis of MDA-MB-231 xenograft tumors. In conclusion, our study demonstrated that activation of GPER can suppress migration and angiogenesis of TNBC via inhibition of NF-κB/IL-6 signals, therefore it maybe act as an important target for TNBC treatment.

Tumour cell invasion into blood vessels is significantly related to breast cancer subtypes and decreased survival

AIMS

Vascular invasion in breast cancer is associated with increased risk of recurrence, metastases and death from disease. However, there are few studies discriminating between blood vessel invasion (BVI) and lymphatic vessel involvement (LVI).

METHODS

A population-based series of 282 breast cancers was examined (200 screen-detected and 82 interval patients) with respect to BVI and LVI in addition to basic features and molecular subtypes, using CD31 and D2-40 antibodies. This series is part of the prospective Norwegian Breast Cancer Screening Program.

RESULTS

The frequency of LVI and BVI was 25% and 15%, respectively. BVI was associated with HER2-positive and basal-like tumours, and several features of aggressive breast cancer, whereas LVI showed weaker associations. BVI was the strongest factor to predict interval cancer presentation. BVI showed significant associations with recurrence-free survival and disease-specific survival in univariate and multivariate analyses, whereas LVI was not significant.

CONCLUSIONS

Our findings indicate that BVI by tumour cells is strongly associated with aggressive tumour features including a basal-like phenotype, and BVI was an independent prognostic factor in contrast to what was found for LVI.

Bevacizumab Addition in Neoadjuvant Treatment Increases the Pathological Complete Response Rates in Patients with HER-2 Negative Breast Cancer Especially Triple Negative Breast Cancer: A Meta-Analysis

Background

Neoadjuvant therapy is administered to breast cancer patients as an induction process before surgery or radiotherapy to reduce tumor size. Human epidermal growth factor receptor-2 (HER-2) negative breast cancer lacks effective standard target therapy. Bevacizumab has a controversial role in the treatment of breast cancer and we conduct a meta-analysis to evaluate the value of adding bevacizumab in neoadjuvant regimen.

Methods

Potentially eligible studies were retrieved using PubMed, EMBASE and Medline. Clinical characteristics of patients and statistical data with pathological complete response (pCR) data were collected. Then a meta-analysis model was established to investigate the correlation between administration of bevacizumab in neoadjuvant therapy and pCR rates in HER-2 negative breast cancer.

Results

Seven eligible studies and 5408 patients were yielded. The pCR rates for “breast” or “breast plus lymph node” were similar. In subgroup analysis, we emphasized on patients with triple-negative breast cancer (TNBC). In the criterion of “lesions in breast” the pooled ORs was 1.55 [1.29, 1.86], P<0.00001 and regarding to the evaluation criterion of “lesions in breast and lymph nodes”, the pooled ORs was 1.48 [1.23, 1.78], P<0.0001, in favor of bevacizumab administration.

Conclusion

According to our pooled results, we finally find that bevacizumab addition as a neoadjuvant chemotherapy component, for induction use with limited cycle to improve the pCR rates and patients may avoid long-term adverse event and long-term invalid survival improvement. Especially in subgroup analysis, pCR rates could be improved significantly and physicians could consider bevacizumab with caution. As patients could avoid the adverse event caused by long-term using of bevacizumab, long-term quality of life improvement may be achieved, especially in TNBC.

Increased angiogenesis is associated with a 32-gene expression signature and 6p21 amplification in aggressive endometrial cancer

Background

Angiogenesis is a hallmark of cancer. The aim of this study was to explore whether microvessel proliferation is associated with gene expression profiles or copy number alterations in endometrial cancer.

Methods

A prospective series of endometrial carcinomas was studied for angiogenesis markers, gene expression profiles, and gene copy number data. For validation, an independent series of endometrial carcinomas as well as an external cohort of endometrial cancer patients were examined by gene expression microarrays.

Results

Increased microvessel proliferation (MVP) was associated with aggressive tumor features and reduced survival, and a 32-gene expression signature was found to separate tumors with high versus low MVP. An increased 32-gene signature score was confirmed to associate with high-grade tumor features and reduced survival by independent cohorts. Copy number studies revealed that amplification of the 6p21 region was significantly associated with MVP, a high 32-gene score, as well as reduced survival.

Conclusion

Increased MVP was significantly associated with aggressive endometrial cancer and reduced survival. Integrated analyses demonstrated significant associations between increased vascular proliferation, amplification of the 6p21 region, VEGF-A mRNA expression, and the 32-gene angiogenesis signature. Our findings indicate amplification of 6p21 as a possible driver of tumor vascular proliferation in endometrial cancer.

Strong Expression of Hypoxia-Inducible Factor-1α (HIF-1α) Is Associated with Axl Expression and Features of Aggressive Tumors in African Breast Cancer

PURPOSE

Inhibition of hypoxia-inducible factor (HIF) and Axl receptor tyrosine kinase is being evaluated for targeted therapy in solid tumors. Both HIF-1α and Axl influence tumor growth and metastatic potential, and they have been linked to treatment failure in many cancers. However, there is a lack of reports on HIF-1α expression in African breast cancer, which has a poor prognosis, and novel treatment targets must therefore be established. Here, we aimed to evaluate HIF-1α in relation to Axl expression, angiogenesis markers, and other tumor characteristics in a series of African breast cancer.

METHODS

Using immunohistochemistry, we examined 261 invasive breast cancers on tissue microarrays for HIF-1α and Axl as well as several other markers, and a subset of 185 cases had information on VEGF (vascular endothelial growth factor) expression, microvessel density (MVD), proliferating microvessel density (pMVD) and vascular proliferation index (VPI) for important comparisons.

RESULTS

Strong HIF-1α expression was associated with increased Axl (p = 0.007), VEGF (p<0.0005), and p53 (p = 0.032) expression, as well as high tumor cell proliferation by Ki-67 (p = 0.006), and high tumor grade (p = 0.003). Tumors with strong HIF-1α expression had significantly higher MVD (p = 0.019) and higher pMVD (p = 0.027) than tumors with weak expression.

CONCLUSIONS

High HIF-1α expression is significantly associated with Axl and VEGF expression, and with markers of poor prognosis in this series of breast cancer, suggesting HIF-1α and Axl as potential therapeutic targets in African breast cancer.

Decreased vascular endothelial growth factor expression is associated with cell apoptosis in low-dose aspirin-induced gastric mucosal injury

BACKGROUND

The use of low-dose aspirin (LDA) has emerged as an important cause of gastrointestinal ulcers. The aim of this study was to investigate the association between LDA-induced gastric mucosal injury and the expression of vascular endothelial growth factor (VEGF) and cell apoptosis in elderly Chinese patients.

METHODS

A total of 136 patients aged 60 to 80 years with LDA-induced (100 mg/d for at least 1 month) gastric mucosal injury and 48 age-matched healthy subjects were enrolled in this study. The patients were divided into a low-severity group and a high-severity group based on their modified Lanza scale scores. Biopsy specimens of gastric mucosa from all participants were subjected to immunohistochemical staining for VEGF expression and terminal deoxynucleotidyl transferase dUTP nick end labeling staining for cell apoptosis. Staining indices and apoptotic indices were applied to assess VEGF expression level and the extent of cell apoptosis.

RESULTS

VEGF expression decreased significantly in the 2 patient groups, whereas the extent of cell apoptosis significantly increased compared with the control group. Furthermore, Spearman's correlation coefficients suggest that VEGF expression levels and the extent of cell apoptosis in gastric mucosae shared a significant correlation with the severity of LDA-induced gastric mucosal injury. Receiver operating characteristics analysis further confirmed these results.

CONCLUSIONS

Our findings provide important clues as to the underlying molecular mechanism behind gastric mucosal injury resulting from exposure to LDA in elderly adults, and also suggest that interventions specifically targeting the pathways associated with angiogenesis and apoptosis may help facilitate the healing process.

Vasculature-specific MRI reveals differential anti-angiogenic effects of a biomimetic peptide in an orthotopic breast cancer model

Translational vasculature-specific MRI biomarkers were used to measure the effects of a novel anti-angiogenic biomimetic peptide in an orthotopic MDA-MB-231 human triple-negative breast cancer model at an early growth stage. In vivo diffusion-weighted and steady-state susceptibility contrast (SSC) MRI was performed pre-treatment and 2 weeks post-treatment in tumor volume-matched treatment and control groups (n = 5/group). Treatment response was measured by changes in tumor volume; baseline transverse relaxation time (T2); apparent diffusion coefficient (ADC); and SSC-MRI metrics of blood volume, vessel size, and vessel density. These vasculature-specific SSC-MRI biomarkers were compared to the more conventional, non-vascular biomarkers (tumor growth, ADC, and T2) in terms of their sensitivity to anti-angiogenic treatment response. After 2 weeks of peptide treatment, tumor growth inhibition was evident but not yet significant, and the changes in ADC or T2 were not significantly different between treated and control groups. In contrast, the vascular MRI biomarkers revealed a significant anti-angiogenic response to the peptide after 2 weeks—blood volume and vessel size decreased, and vessel density increased in treated tumors; the opposite was seen in control tumors. The MRI results were validated with histology—H&E staining showed no difference in tumor viability between groups, while peptide-treated tumors exhibited decreased vascularity. These results indicate that translational SSC-MRI biomarkers are able to detect the differential effects of anti-angiogenic therapy on the tumor vasculature before significant tumor growth inhibition or changes in tumor viability.

Angiogenesis and tumor microenvironment: bevacizumab in the breast cancer model

Solid tumors require blood vessels for growth, and many new cancer therapies are directed against the tumor vasculature. Antiangiogenic therapies should destroy the tumor vasculature, thereby depriving the tumor of oxygen and nutrients. According to Jain et al., an alternative hypothesis could be that certain antiangiogenic agents can also transiently "normalize" the abnormal structure and function of tumor vasculature to make it more efficient for oxygen and drug delivery. With emphasize on the research works of Jain et al., the aim of this review is to describe the impact of antivascular endothelial growth factor (VEGF) therapy on "pseudo-normalization" of tumor vasculature and tumor microenvironment, its role in early and metastatic breast cancer, and the clinical evidence supporting this original concept. The phase III clinical trials showed that extended tumors, metastatic or locally advanced, are likely to benefit from bevacizumab therapy in combination with chemotherapy, assuming that a high level of tumor neoangiogenesis as in triple-negative tumors is the best target. In adjuvant setting, the lower level of tumor vasculature could mask a potential benefit of anti-VEGF therapy. All these findings highlight the need to identify biomarkers to help in the selection of patients most likely to respond to anti-VEGF therapy, to better understand the mechanism of angiogenesis and of resistance to anti-VEGF therapy according to molecular subtypes.

Neoadjuvant bevacizumab and anthracycline-taxane-based chemotherapy in 678 triple-negative primary breast cancers; results from the geparquinto study (GBG 44)

BACKGROUND

We evaluated the pathological complete response (pCR) rate after neoadjuvant epirubicin, (E) cyclophosphamide (C) and docetaxel containing chemotherapy with and without the addition of bevacizumab in patients with triple-negative breast cancer (TNBC).

PATIENTS AND METHODS

Patients with untreated cT1c-4d TNBC represented a stratified subset of the 1948 participants of the HER2-negative part of the GeparQuinto trial. Patients were randomized to receive four cycles EC (90/600 mg/m(2); q3w) followed by four cycles docetaxel (100 mg/m(2); q3w) each with or without bevacizumab (15 mg/kg; q3w) added to chemotherapy.

RESULTS

TNBC patients were randomized to chemotherapy without (n = 340) or with bevacizumab (n = 323). pCR (ypT0 ypN0, primary end point) rates were 27.9% without and 39.3% with bevacizumab (P = 0.003). According to other pCR definitions, the addition of bevacizumab increased the pCR rate from 30.9% to 41.8% (ypT0 ypN0/+; P = 0.004), 36.2% to 46.4% (ypT0/is ypN0/+; P = 0.009) and 32.9% to 43.3% (ypT0/is ypN0; P = 0.007). Bevacizumab treatment [OR 1.73, 95% confidence interval (CI) 1.23-2.42; P = 0.002], lower tumor stage (OR 2.38, 95% CI 1.24-4.54; P = 0.009) and grade 3 tumors (OR 1.68, 95% CI 1.14-2.48; P = 0.009) were confirmed as independent predictors of higher pCR in multivariate logistic regression analysis.

CONCLUSIONS

The addition of bevacizumab to chemotherapy in TNBC significantly increases pCR rates.

Endothelial-like properties of claudin-low breast cancer cells promote tumor vascular permeability and metastasis

The vasculature serves as the main conduit for breast tumor metastases and is a target of therapeutics in many tumor types. In this study, we aimed to determine if tumor-associated vascular properties could help to explain the differences observed in metastagenicity across the intrinsic subtypes of human breast tumors. Analysis of gene expression signatures from more than 3,000 human breast tumors found that genomic programs that measured vascular quantity, vascular proliferation, and a VEGF/Hypoxia-signature were the most highly expressed in claudin-low and basal-like tumors. The majority of the vascular gene signatures added metastasis-predictive information to immunohistochemistry-defined microvessel density scores and genomically defined-intrinsic subtype classification. Interestingly, pure claudin-low cell lines, and subsets of claudin-low-like cells within established basal-like cancer cell lines, exhibited endothelial/tube-like morphology when cultured on Matrigel. In vivo xenografts found that claudin-low tumors, but not luminal tumors, extensively perfused injected contrast agent through paracellular spaces and non-vascular tumor-lined channels. Taken together, the endothelial-like characteristics of the cancer cells, combined with both the amount and the physiologic state of the vasculature contribute to breast cancer metastatic progression. We hypothesize that the genetic signatures we have identified highlight patients that should respond most favorably to anti-vascular agents.

A Phase I dose-escalation study of the VEGFR inhibitor tivozanib hydrochloride with weekly paclitaxel in metastatic breast cancer

Tivozanib is a potent selective tyrosine kinase inhibitor (TKI) of vascular endothelial growth factor receptors (VEGFRs) 1, 2, and 3. This Phase Ib study investigated the safety/tolerability, pharmacokinetics (PK), and activity of tivozanib with weekly paclitaxel in metastatic breast cancer (MBC). MBC patients with no prior VEGFR TKI treatment received daily oral tivozanib (3 weeks on, 1 week off) with weekly paclitaxel 90 mg/m(2). Standard 3 + 3 dose escalation was used; tivozanib cohorts (C) included C1 0.5 mg, C2 1.0 mg, and C3 1.5 mg. Assessments included Response Evaluation Criteria in Solid Tumors response, PK, and vascular function. Eighteen patients enrolled. Toxicities in >20 % of patients included fatigue, alopecia, nausea, diarrhea, peripheral sensory neuropathy, and hypertension. Grade 3/4 toxicities in >15 % of patients included fatigue and neutropenia. Maximum tolerated dose was tivozanib 1.5 mg with paclitaxel 90 mg/m(2). Four patients withdrew because of toxicity and one due to progressive disease. Thirteen patients were evaluable for response: four (30.8 %) had confirmed partial response; four had stable disease ≥6 months (30.8 %). PK data suggest no influence of paclitaxel on tivozanib concentrations. Tivozanib plus weekly paclitaxel was tolerable at all dose levels, supporting their combination at full dose. Activity in this small population was encouraging.

The estimation of metaloproteinases and their inhibitors blood levels in patients with pancreatic tumors

Background

The aim of the study was to evaluate the concentration of proteolytic enzymes, MMP-2 and MMP-9, and their tissue inhibitors, TIMP-1 and TIMP-2, in the blood of patients with benign and malignant pancreatic tumors.

Methods

MMP-2, MMP-9, TIMP-1, and TIMP-2 were evaluated in the patients with benign and malignant pancreatic tumors before surgery and in the 30-day follow-up. The study covered 134 patients aged 54 to 76 years, who were divided into groups by TNM staging.

Results

Before the operation, the highest mean concentration of MMP-2 was found in patients with unresectable cancer, whereas the highest level of MMP-9 was in patients with resectable cancer. The highest level of TIMP-1 was noted in patients with inflammatory tumors. In 1 month following the operation, the highest level of MMP-2 was also in patients with unresectable cancer and the highest level of TIMP-2 in patients with inflammatory tumors.

Conclusions

The evaluation of the level of the studied cytokines in the pancreatic tumor patients can be diagnostically significant in the differentiation of benign and malignant changes. The changes in the levels of the studied enzymes and their inhibitors can have a prognostic value in the clinical severity of pancreatic cancer.

Low-molecular contrast agent dynamic contrast-enhanced (DCE)-MRI and diffusion-weighted (DW)-MRI in early assessment of bevacizumab treatment in breast cancer xenografts

PURPOSE

To investigate the effect of bevacizumab treatment on vascular architecture and function in two xenograft models with different angiogenic properties using diffusion-weighted magnetic resonance imaging (DW-MRI) and dynamic contrast-enhanced MRI (DCE-MRI).

MATERIALS AND METHODS

Mice carrying basal-like (MAS98.12) or luminal-like (MAS98.06) orthotopic breast cancer xenografts were treated with bevacizumab (5 mg/kg), doxorubicin (8 mg/kg), or both drugs in combination. DW-MRI and DCE-MRI were performed before and 3 days after treatment using a Bruker 7T preclinical scanner. Mean microvessel density (MVD) and proliferating microvessel density (pMVD) in the tumors were determined for evaluation of vascular response to bevacizumab treatment.

RESULTS

No changes in DCE-MRI or DW-MRI parameters were observed in untreated controls during the experiment period. DW-MRI showed increased apparent diffusion coefficient (ADC) values in all treatment groups in both basal-like and luminal-like xenografts. DCE-MRI showed increased contrast agent uptake, particularly in central regions of the tumors, after bevacizumab/combination treatment in both xenograft models. This was accompanied by decreased MVD and pMVD in basal-like xenografts. Doxorubicin treatment had no effect on DCE-MRI parameters in any of the xenograft models.

CONCLUSION

Both DW-MRI and DCE-MRI demonstrated an early response to bevacizumab treatment in the xenograft tumors. Increased contrast agent uptake and reduced MVD/pMVD is consistent with a normalization of vascular function.

Molecular hierarchy of heparin-binding EGF-like growth factor-regulated angiogenesis in triple-negative breast cancer

Heparin-binding EGF-like growth factor (HB-EGF) is one of several proangiogenic factors and represents a possible therapeutic target for patients with triple-negative breast cancer (TNBC). However, the role of HB-EGF in promoting tumor aggressiveness in TNBC remains unclear. To investigate specific genes and pathways involved in TNBC tumorigenesis, we profiled gene expression changes in two TNBC cell lines under two-dimensional culture (2DC) and three-dimensional culture (3DC) and in a tumor xenograft model. We identified simultaneous upregulation of HB-EGF, VEGFA, and angiopoietin-like 4 (ANGPTL4) in 3DC and tumor xenografts, compared with 2DC. We show that HB-EGF regulates the expression of VEGFA or ANGPTL4 via transcriptional regulation of hypoxia-inducible factor-1α and NF-κB. Furthermore, suppression of VEGFA or ANGPTL4 expression enhanced HB-EGF expression, highlighting a unique regulatory loop underlying this angiogenesis network. Targeted knockdown of HB-EGF significantly suppressed tumor formation in a TNBC xenograft model, compared with individual knockdown of either VEGFA or ANGPTL4, by reducing the expression of both VEGFA and ANGPTL4. In patients with TNBC, VEGFA or ANGPTL4 expression was also significantly correlated with HB-EGF expression. Low concentrations of exogenously added HB-EGF strongly activated the proliferation of endothelial cells, tube formation, and vascular permeability in blood vessels, in a similar fashion to high doses of VEGFA and ANGPTL4. Taken together, these results suggest that HB-EGF plays a pivotal role in the acquisition of tumor aggressiveness in TNBC by orchestrating a molecular hierarchy regulating tumor angiogenesis.

Cardiac side effects of anticancer treatments: new mechanistic insights

Damage to heart cells leading to heart failure is a known complication of well-established cancer therapies including anthracycline antibiotics and radiation therapy, and the cardiovascular complications of these therapies has been controlled in large part through dose limitations and modifications of delivery methods. Recent research into the cellular and molecular mechanisms for the cardiovascular effects of these therapies may lead to other cardioprotective strategies that improve effectiveness of cancer treatments. Newer cancer therapies that have been developed based upon specifically targeting oncogene signaling also have been associated with heart failure. Rapid development of a detailed understanding of how these agents cause cardiac dysfunction promises to improve outcomes in cancer patients, as well as stimulate concepts of cardiovascular homeostasis that will likely accelerate development of cardiovascular therapies.

Microvessel proliferation by co-expression of endothelial nestin and Ki-67 is associated with a basal-like phenotype and aggressive features in breast cancer

BACKGROUND

To quantify tumour angiogenesis, microvessel density (MVD) has been widely used. We here present a novel angiogenesis marker, microvessel proliferation (MVP), based on dual immunohistochemical staining of nestin and Ki-67. Immature endothelial cells express nestin, and when co-expressed with the proliferation marker Ki-67, the number of proliferating immature blood vessels can be measured.

MATERIALS AND METHODS

Microvessel proliferation was evaluated in 178 breast cancer samples and estimated by vascular proliferation index (VPI), the ratio between the number of vessels containing proliferating endothelial cells and the total number of immature vessels.

RESULTS

High VPI was strongly associated with several markers of aggressive breast cancer, such as negative oestrogen receptor (ER) status (p = 0.003), high tumour cell proliferation by Ki-67 (p = 0.004), high p53 expression (p = 0.001), and five profiles for the basal-like phenotype (odds ratios (OR); range 3.4-6.3). Also, high VPI was significantly associated with interval detected breast cancer compared with screening detected lesions (p < 0.0005), and adverse outcome in univariate and multivariate survival analysis (p = 0.034 and p = 0.022, respectively).

CONCLUSION

Microvessel proliferation is a novel marker of ongoing angiogenesis and was associated with aggressive tumour features, basal-like phenotypes, interval presentation, and prognosis in this series of breast cancer.

A triple negative breast cancer: what it is not!

The triple negative cancer is an unusual, and at the same time, a unique entity where the discordance rate is almost 18%. That means 18% of Her2 negative results will transform into a Her2 positive status and will have the affinity to spread to the central nervous system (CNS). With the identification of CD44, CD24, and ALDH1, we may be able to determine which group of triple negative breast cancer patients will have CNS metastasis. This case illustrates the Her2 expressing cells have higher CNS affinity. As the original tumor was Her2 negative, if a genomic assay was then done on this patient, we would have identified the potential of CNS involvement. In conclusion, genomic assays should be routinely done on triple negative cancers.