Project description:Approximately half of women diagnosed with advanced triple negative breast cancer (TNBC) will develop brain metastases, of which the majority will have uncontrolled extracranial disease. While local therapies to treat brain metastases are standardly prescribed, survival remains less than 6 months. This phase II, multi-center trial evaluated efficacy of irinotecan and iniparib, anti-cancer agents with activity in TNBC and known to cross the blood brain barrier, among 34 patients with new or progressive TNBC brain metastases. While time to progression was short (2.1 months), 27% of patients experienced intracranial clinical benefit and therapy was well-tolerated. Correlative studies illustrate partial response was associated with germline BRCA mutation status and high tumor expression of proliferation genes and signatures. To our knowledge, this is the first study showing feasibility of enrolling patients with progressive TNBC brain metastases to a systemic therapy and lays the groundwork for future studies to treat this devastating disease.
Project description:Chemotherapy is the mainstay treatment stragety for triple negative breast cancer (TNBC). However resistance to chemotherapy is common, leading to disease progression and death. Strategies that improve chemotherapy efficacy has the potential to reduce TNBC mortality. In this research, we demonstrated that the pan-PI3K inhibitor copanlisib, which is already in clinic to treat hematologic malignancies, enhanced the cytotoxicity of eribulin, a common chemotherapy used to treat taxane-resistant TNBC, in a panel of TNBC patient-derived xenograft (PDX) models. The improved tumor growth inhibition was irrespective of PI3K pathway alteration and was corroborated by the enhanced apoptotic induction observed in PDX tumors post combination therapy compared to each drug alone. The combination therapy inhibited eribulin-induced PI3K pathway activation, providing an underlying mechanism of action for its enhanced anti-tumor effect. Based on these results, a Phase I/II trial of this combination in patients with metastatic TNBC was initiated and is ongoing.
Project description:Advanced colorectal cancer (CRC) is an unresolved clinical problem. Epigenetic drugs belonging to the group of histone deacetylase inhibitors (HDACi) may combat CRC in rationally designed treatment schedules. Unfortunately, there is sparse evidence on molecular mechanisms and markers that determine cellular sensitivity to HDACi. Irinotecan is widely used to treat CRC and causes replication stress (RS) and DNA damage as topoisomerase-I inhibitor. We applied irinotecan and the class I HDACi entinostat (MS-275) to isogenic p53-positive and -negative CRC cells. Combinations of irinotecan and MS-275 evoke mitochondrial damage, caspase-mediated apoptosis, and RS-associated DNA damage synergistically and p53-dependently. Targeted mass spectrometry and immunoblot show that irinotecan induces phosphorylation, acetylation, and accumulation of p53 and its target genes. Addition of MS-275 augments the irinotecan-induced acetylation of C-terminal lysine residues of p53 but decreases its phosphorylation and p53 target gene induction. Furthermore, MS-275 increases the amount of acetylated p53 at mitochondria and dysregulates the expression of pro- and anti-apoptotic BCL2 proteins in irinotecan-treated cells. Regarding DNA repair, we see that MS-275 represses the homologous recombination (HR) filament protein RAD51, which limits DNA damage and pro-apoptotic effects of irinotecan. These data suggest that key class I HDAC-dependent functions of p53 in cells with RS are linked to mitochondrial damage and a breakdown of HR. Most importantly, combinations of irinotecan plus MS-275 also kill short-term primary CRC cell cultures and organoids from CRC patients but spare organoids of adjacent matched normal tissue. Thus, irinotecan/HDACi treatment is a promising new approach for the therapy of p53-proficient tumors with clinically tractable inhibitors.
Project description:The aim of this study was evaluate the transcriptome changes in the comparison between triple negative tumors with increased SPARC expression and triple negative tumors with decreased SPARC expression according to Nagai et al., 2011 (Breast Cancer Res Treat (2011) 126:1–14) The results generated could be of particular interest to better define the prognostic impact of SPARC expression in triple negative breast tumors
Project description:Traditional Chinese Medicine (TCM) has been used for thousands of years to treat or prevent diseases, including cancer. Good manufacturing practices (GMP) and sophisticated product analysis (PhytomicsQC) to ensure consistency are now available allowing the assessment of its utility. Polychemical Medicines, like TCM, include chemicals with distinct tissue-dependent pharmacodynamic properties that result in tissue-specific bioactivity. Determining the mode of action of these mixtures was previously unsatisfactory; however, information rich RNA microarray technologies now allow for thorough mechanistic studies about complex mixtures effects. PHY906 is a long used four herb TCM formula employed as adjuvant to relieve side effects associated with chemotherapy. Animal studies documented a decrease in global toxicity and an increase in therapeutic effectiveness of chemotherapy when PHY906 was combined. Using a systems biology approach, we studied tumor tissue to identify reasons for the enhancement of the antitumor effect of Irinotecan by PHY-906 in a well-characterized pre-clinical model; PHY-906 and Irinotecan were administered orally to female BDF-1 mice bearing subcutaneous Colon 38 tumors. We observed that 1) individually PHY-906 and Irinotecan induce distinct alterations in tumor, liver and spleen; 2) PHY-906 alone predominantly induces repression of transcription and immune-suppression in tumors; 3) these effects are reverted in the presence of Irinotecan, with prevalent induction of pro-apoptotic and pro-inflammatory pathways that may favor tumor rejection. Most importantly, PHY-906 together with Irinotecan triggers unique changes not activated by each one alone suggesting that the combination creates a unique tissue-specific response. Four groups of BDF-1 mice bearing colon 38 tumors were treated with Phosphate Buffered Saline (PBS) (n=10), PHY-906 (n=10), Irinotecan (CPT-11, Camptosar(TM)) (n=10) or the combination PHY-906 and Irinotecan (n=10). Tumor (38 samples), spleen (38 samples), and liver (35 samples) tissues were removed and frozen for total RNA isolation and subsequent microarray hybridization. There were a total of 111 samples representing 12 treated tissue groups with 8 to 10 biological replicates each. A reference sample was generated from a pool of mixed normal mouse tissue.
Project description:Breast cancer in young patients is known to exhibit more aggressive biological behavior and is associated with a less favorable prognosis than the same disease in older patients, owing in part to an increased incidence of brain metastases, the mechanistic explanations behind which remain poorly understood. We recently reported that young mice, compared to older mice, showed about a three-fold increase in the development of brain metastases in mouse models of triple-negative and luminal B breast cancer. Here we have performed a quantitative mass spectrometry-based proteomic analysis to identify proteins contributing to age-related disparities in the development of breast cancer brain metastases. Using a mouse model of brain-tropic (MDA-MB-231BR) triple-negative breast cancer, we harvested subpopulations of tumor metastases, the tumor-adjacent metastatic microenvironment, and uninvolved brain tissues via laser microdissection followed by quantitative proteomic analysis using high resolution mass spectrometry to characterize differentially abundant proteins contributing to age-dependent rates of brain metastasis.
Project description:Analysis of lung and liver metastases derived from M-Wnt primary tumor. Results provide insight into genes associated with progression of triple negative breast cancer to metastatic disease.