Increased risk of brain metastases in women with breast cancer and p16 expression in metastatic lymph-nodes

Recent advances in breast cancer metastasis with special emphasis on metastasis to the brain

Understanding the underlying mechanisms of breast cancer metastasis is of vital importance for developing treatment approaches. This review emphasizes contemporary breakthrough studies with special focus on breast cancer brain metastasis. Acquired mutational changes in metastatic lesions are often distinct from the primary tumor, suggesting altered mutagenesis pathways. The concept of micrometastases and heterogeneity within the tumors unravels novel therapeutic targets at genomic and molecular levels through epigenetic and proteomic profiling. Several pre-clinical studies have identified mechanisms involving the immune system, where tumor associated macrophages are key players. Expression of cell proteins like Syndecan1, fatty acid-binding protein 7 and tropomyosin kinase receptor B have been implicated in aiding the transmigration of breast cancer cells to the brain. Changes in the proteomic landscape of the blood-brain-barrier show altered permeability characteristics, supporting entry of cancer cells. Findings from laboratory studies pave the path for the emergence of new biomarkers, especially blood-based miRNA and circulating tumor cell markers for prognostic staging. The constantly evolving therapeutics call for clinical trials backing supportive evidence of efficacies of both novel and existing approaches. The challenge lying ahead is discovering innovative techniques to replace use of human samples and optimize small-scale patient recruitment in trials.

Immunoexpression of HER2 pathway related markers in HER2 invasive breast carcinomas treated with trastuzumab

PURPOSE

We evaluated the immunoexpression of potential markers involved in the HER2 pathway in invasive breast carcinoma with HER2 amplification treated with trastuzumab.

METHODS

Samples of ninety patients diagnosed and treated at two public Brazilian hospitals with overexpressed invasive carcinoma between 2009 and 2018 were included. Several markers (Bcl-2, CDK4, cyclin D1, EGFR, IGF1, IGF-1R, MDM2, MUC4, p16, p21, p27, p53, PTEN, RA, TNFα, and VEGF) were immune analyzed in the tumor by immunohistochemistry and then correlated with clinicopathological variables.

RESULTS

Tumor sample expression results determined potential markers of good prognosis with statistically significant values: cyclin D1 with a nuclear grade, and recurrence; IGF-1 with tumor size, and death; p16 with a response after treatment; PTEN with a response after treatment, and death. Markers of poor prognosis: p53 with histological, and nuclear grade; IGF-1R with a compromised lymph node. The treatment resistance rate after trastuzumab was 40%; the overall survival was 4.13 years (95% CI 5.1-12.5) and the disease-free survival was 3.6 years (95% CI 5.1-13.1).

CONCLUSIONS

The tumor samples profile demonstrated that cyclin D1, IGF-1, p16, and PTEN presented the potential for a good prognosis and p53 and IGF-1R for worse.

The effects of statin therapy on brain tumors, particularly glioma: a review

Brain tumors account for less than 2% of all malignancies. However, they are associated with the highest morbidity and mortality rates among all solid tumors. The most common malignant primary brain tumors are glioma or glioblastoma (GBM), which have a median survival time of about 14 months, often suffer from recurrence after a few months following treatment, and pose a therapeutic challenge. Despite recent therapeutic advances, the prognosis for glioma patients is poor when treated with modern therapies, including chemotherapy, surgery, radiation, or a combination of these. Therefore, discovering a new target to treat brain tumors, particularly glioma, might be advantageous in raising progression-free survival and overall survival (OS) rates. Statins, also known as competitive HMG-CoA reductase inhibitors, are effective medications for reducing cholesterol and cardiovascular risk. The use of statins prior to and during other cancer treatments appears to enhance patient outcomes according to preclinical studies. After surgical resection followed by concurrent radiation and treatment, OS for patients with GBM is only about a year. Statins have recently emerged as potential adjuvant medications for treating GBM due to their ability to inhibit cell growth, survival, migration, metastasis, inflammation, angiogenesis, and increase apoptosis in-vitro and in-vivo studies. Whether statins enhance clinical outcomes, such as patient survival in GBM, is still debatable. This study aimed to explore the effects of statin therapy in the context of cancer treatment, with a particular focus on GBM.

Utilizing cell-free DNA to predict risk of developing brain metastases in patients with metastatic breast cancer

We compared cell-free DNA (cfDNA) results at MBC diagnosis in patients who developed brain metastases (BM) vs those without (non-BM) to understand genomic predictors of BM. Patients with cfDNA testing at MBC diagnosis (Guardant360®, 73 gene next generation sequencing) were identified. Clinical and genomic features of BM and non-BM were compared (Pearson's/Wilcoxon rank sum tests). Eighteen of 86 patients (21%) with cfDNA at MBC diagnosis developed BM. Comparing BM vs non-BM, a higher prevalence of BRCA2 (22% vs 4.4%, p = 0.01), APC (11% vs 0%, p = 0.005), CDKN2A (11% vs 1.5%, p = 0.05), and SMAD4 (11% vs 1.5%, p = 0.05) was observed. Seven of 18 BM had ≥1 of the following 4 mutations in baseline cfDNA: APC, BRCA2, CDKN2A or SMAD4 vs 5/68 non-BM (p = 0.001). Absence of this genomic pattern had a high negative predictive value (85%) and specificity (93%) in excluding BM development. Baseline genomic profile varies in MBC that develops BM.

Genomics of Breast Cancer Brain Metastases: A Meta-Analysis and Therapeutic Implications

Breast cancer brain metastases are a challenging daily practice, and the biological link between gene mutations and metastatic spread to the brain remains to be determined. Here, we performed a meta-analysis on genomic data obtained from primary tumors, extracerebral metastases and brain metastases, to identify gene alterations associated with metastatic processes in the brain. Articles with relevant findings were selected using Medline via PubMed, from January 1999 up to February 2022. A critical review was conducted according to the Preferred Reporting Items for Systematic Review and Meta-analysis statement (PRISMA). Fifty-seven publications were selected for this meta-analysis, including 37,218 patients in all, 11,906 primary tumor samples, 5541 extracerebral metastasis samples, and 1485 brain metastasis samples. We report the overall and sub-group prevalence of gene mutations, including comparisons between primary tumors, extracerebral metastases and brain metastases. In particular, we identified six genes with a higher mutation prevalence in brain metastases than in extracerebral metastases, with a potential role in metastatic processes in the brain: ESR1, ERBB2, EGFR, PTEN, BRCA2 and NOTCH1. We discuss here the therapeutic implications. Our results underline the added value of obtaining biopsies from brain metastases to fully explore their biology, in order to develop personalized treatments.

Molecular aspects of brain metastases in breast cancer

Brain metastases (BM) are a common and devastating manifestation of breast cancer (BC). BM are particularly frequent in the HER2-positive and triple-negative breast cancer phenotypes and usually occur following the metastatic spread to extracranial sites. Several genes mediating BM and biomarkers predicting their risk in BC have been reported in the past decade. These findings have advanced the understanding of BM pathobiology and paved the way for developing new therapeutic strategies but they still warrant a thorough clinical validation. Hence, a better understanding of the mechanistic aspects of BM and delineating the interactions of tumor cells with the brain microenvironment are of utmost importance. This review discusses the molecular basis of the metastatic cascade: the epithelial-mesenchymal transition, cancer, and tumor microenvironment interaction and intravasation, priming of the metastatic niche in the brain, and survival in the new site. We also outline the postulated mechanisms of BC cells' brain tropism. Finally, we discuss advances in the field of biomarkers (both tissue-based and liquid-based) that predict BM from BC.

Risk factors for breast cancer brain metastases: a systematic review

Background: Brain metastasis (BM) is an increasingly common and devastating complication of breast cancer (BC).

Methods: A systematic literature search of EMBASE and MEDLINE was conducted to elucidate the current state of knowledge on known and novel prognostic factors associated with 1) the risk for BCBM and 2) the time to brain metastases (TTBM).

Results: A total of 96 studies involving institutional records from 28 countries were identified. Of these, 69 studies reported risk factors of BCBM, 46 factors associated with the TTBM and twenty studies examined variables for both outcomes. Young age, estrogen receptor negativity (ER-), overexpression of human epidermal factor (HER2+), and higher presenting stage, histological grade, tumor size, Ki67 labeling index and nodal involvement were consistently found to be independent risk factors of BCBM. Of these, triple-negative BC (TNBC) subtype, ER-, higher presenting histological grade, tumor size, and nodal involvement were also reported to associate with shorter TTBM. In contrast, young age, hormone receptor negative (HR-) status, higher presenting stage, nodal involvement and development of liver metastasis were the most important risk factors for BM in HER2-positive patients.

Conclusions: The study provides a comprehensive and individual evaluation of the risk factors that could support the design of screening tools and interventional trials for early detection of BCBM.

Genomics applied to the treatment of breast cancer

Breast cancer remains a major health issue in the world with 1.7 million new cases in 2012 worldwide. It is the second cause of death from cancer in western countries. Genomics have started to modify the treatment of breast cancer, and the developments should become more and more significant, especially in the present era of treatment personalization and with the implementation of new technologies. With molecular signatures, genomics enabled a de-escalation of chemotherapy and personalized treatments of localized forms of estrogen-dependent breast cancers. Genomics can also make a real contribution to constitutional genetics, so as to identify mutations in a panel of candidate genes. In this review, we will discuss the contributions of genomics applied to the treatment of breast cancer, whether already validated contributions or possible future applications linked to research data.

Overexpression of P16 reversed the MDR1-mediated DDP resistance in the cervical adenocarcinoma by activating the ERK1/2 signaling pathway

Background

To investigate the role of P16 (INK4a)-extracellular signal related kinase 1/2 (ERK1/2) signaling pathway in cisplatin (DDP) resistance induced by multidrug resistance protein 1 (MDR1), also known as P-glycoprotein (P-gp), in cervical adenocarcinoma.

Methods

A human DDP-resistant HeLa cell line (HeLa/DDP) was constructed using the combination of incremental and intermittent administration of DDP. Cell Counting Kit-8 (CCK-8) assay was used to measure the IC50 and resistance index (RI) of cells. The morphological changes and population doubling time were observed under an inverted microscope. Plate cloning formation assay was performed to evaluate the cell proliferation and tumorigenic ability. Cell invasion and migration were determined by transwell assays. Besides, the expression of P16, phosphorylated extracellular signal related kinase 1 and 2 (pERK1/2), total ERK1/2 and MDR1 were measured using western blot analysis. The ERK-specific inhibitor U0126 and agonist TPA was used to explore the role of ERK.

Results

The DDP-resistant cervical adenocarcinoma HeLa/DDP cell line was successfully established, which showed stronger cell growth, invasion, and migration. In the HeLa/DDP cells, pERK1/2 was downregulated, P-gp was upregulated and P16 was downregulated. Overexpression of P16 led to a significant decrease in the proliferation rate, migration ability, and invasion ability of the HeLa/DDP cells. Furthermore, overexpression of P16 increased and the decreased expression of pERK1/2 and P-gp in the HeLa/DDP cells, respectively. Treatment of HeLa/DDP cells transfected with P16 plasmid with ERK-specific inhibitor U0126 significantly decreased the expression of pERK1/2 and increased the expression of P-gp from 6 h to 48 h. Moreover, after 72 h, the expression of pERK1/2 was up-regulated and the expression of P-gp was inhibited.

Conclusion

Overexpression of P16 could partially reverse the MDR1-mediated DDP resistance in the cervical adenocarcinoma by the enhancement of phosphorylation of ERK signaling pathway, which provided a theoretical basis for the treatment of DDP resistance in cervical adenocarcinoma.

Electronic supplementary material

The online version of this article (10.1186/s13008-019-0048-6) contains supplementary material, which is available to authorized users.