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IMPORTANCE: Triple-negative breast cancer (TNBC) classified by transcriptional profiling as the mesenchymal subtype frequently harbors aberrations in the phosphoinositide 3-kinase (PI3K) pathway, raising the possibility of targeting this pathway to enhance chemotherapy response. Up to 30% of mesenchymal TNBC can be classified histologically as metaplastic breast cancer, a chemorefractory group of tumors with a mixture of epithelial and mesenchymal components identifiable by light microscopy. While assays to identify mesenchymal TNBC are under development, metaplastic breast cancer serves as a clinically identifiable surrogate to evaluate potential regimens for mesenchymal TNBC. OBJECTIVE: To assess safety and efficacy of mammalian target of rapamycin (mTOR) inhibition in combination with liposomal doxorubicin and bevacizumab in patients with advanced metaplastic TNBC. DESIGN, SETTING, AND PARTICIPANTS: Phase 1 study with dose escalation and dose expansion at the University of Texas MD Anderson Cancer Center of patients with advanced metaplastic TNBC. Patients were enrolled from April 16, 2009, to November 4, 2014, and followed for outcomes with a cutoff date of November 1, 2015, for data analysis. INTERVENTIONS: Liposomal doxorubicin, bevacizumab, and the mTOR inhibitors temsirolimus or everolimus using 21-day cycles. MAIN OUTCOMES AND MEASURES: Safety and response. When available, archived tissue was evaluated for aberrations in the PI3K pathway. RESULTS: Fifty-two women with metaplastic TNBC (median age, 58 years; range, 37-79 years) were treated with liposomal doxorubicin, bevacizumab, and temsirolimus (DAT) (N = 39) or liposomal doxorubicin, bevacizumab, and everolimus (DAE) (N = 13). The objective response rate was 21% (complete response = 4 [8%]; partial response = 7 [13%]) and 10 (19%) patients had stable disease for at least 6 months, for a clinical benefit rate of 40%. Tissue was available for testing in 43 patients, and 32 (74%) had a PI3K pathway aberration. Presence of PI3K pathway aberration was associated with a significant improvement in objective response rate (31% vs 0%; P = .04) but not clinical benefit rate (44% vs 45%; P > .99). CONCLUSIONS AND RELEVANCE: Using metaplastic TNBC as a surrogate for mesenchymal TNBC, DAT and DAE had notable activity in mesenchymal TNBC. Objective response was limited to patients with PI3K pathway aberration. A randomized trial should be performed to test DAT and DAE for metaplastic TNBC, as well as nonmetaplastic, mesenchymal TNBC, especially when PI3K pathway aberrations are identified.

AbstractFungal taxonomy and ecology have been revolutionized by the application of molecular methods and both have increasing connections to genomics and functional biology. However, data streams from traditional specimen- and culture-based systematics are not yet fully integrated with those from metagenomic and metatranscriptomic studies, which limits understanding of the taxonomic diversity and metabolic properties of fungal communities. This article reviews current resources, needs, and opportunities for sequence-based classification and identification (SBCI) in fungi as well as related efforts in prokaryotes. To realize the full potential of fungal SBCI it will be necessary to make advances in multiple areas. Improvements in sequencing methods, including long-read and single-cell technologies, will empower fungal molecular ecologists to look beyond ITS and current shotgun metagenomics approaches. Data quality and accessibility will be enhanced by attention to data and metadata standards and rigorous enforcement of policies for deposition of data and workflows. Taxonomic communities will need to develop best practices for molecular characterization in their focal clades, while also contributing to globally useful datasets including ITS. Changes to nomenclatural rules are needed to enable validPUBLICation of sequence-based taxon descriptions. Finally, cultural shifts are necessary to promote adoption of SBCI and to accord professional credit to individuals who contribute to community resources.

PURPOSE: Cancer is a manifestation of aberrant cellular proliferation, and the cell cycle is one of the most successfully drugged targets in oncology. No prior study has been reported that simultaneously targets the 3 principal cell cycle phases populated by proliferating cells - G1, S, and G2/M.METHODS: Temsirolimus (G1inhibitor), topotecan (S inhibitor), and bortezomib (G2/M inhibitor) were administered in combination to patients with advanced malignancies using a 3+3 dose escalation schedule to assess the safety and establish the maximum tolerated dose (primary endpoints) of this cell cycle targeting approach. An in silicopharmacodynamic model using established effects of each of these agents on the cell cycle was used to validate the regimen and to guide the dosing regimen.RESULTS: Sixty-two subjects were enrolled. The most common adverse events and dose-limiting toxicities were cytopenias, consistent with the cell cycle targeting approach employed. All cytopenias resolved to baseline values upon holding study drug administration. The maximum tolerated dose was temsirolimus 15 mg/kg IV D1, 8, 15; topotecan 2.8 mg/m2IV D1, 8; and bortezomib 0.9 mg/m2IV D1, 4, 8, 11 of a 21-day cycle. In silicomodeling suggests the regimen induces cell population shifts from G2/M and S phases to G1phase and the quiescent G0phase. Eighteen percent of subjects (11/62) achieved partial response (n = 2, serous ovarian and papillary thyroid) or stable disease for > 6 months (n = 9).CONCLUSION: Combining drugs with inhibitory activity of G1phase, S phase, and G2/M phase is safe and warrants further evaluation.

Our laboratory has identified at least two types of vascular smooth muscle cells (VSMCs) that exist in canine arteries and veins: type 1 cells, located in the media express muscle specific proteins but do not proliferate in culture; and type 2 cells, located in both media and adventitia, do not express muscle specific protein but proliferate in culture. Plasma membrane Ca2+-ATPases (PMCAs) have been implicated in proliferation control. The present study examines the expression of PMCA isoforms and calmodulin-binding domain splice variants in these two types of canine VSMCs. PMCA protein was found in both type 1 and type 2 cells. Reverse transcriptase–polymerase chain reaction assays were developed for canine PMCA calmodulin-binding domain splice variants. We cloned and sequenced isolates corresponding to PMCA1b, 4a and 4b from canine VSMCs. PMCA 2 and 3 were not detected. Freshly isolated type 1 cells expressed PMCA 1b, 4a and 4b, while freshly isolated type 2 cells expressed PMCA1b and 4b. Upon placement in culture, type 2 cells originating from either carotid artery or saphenous vein demonstrated a time-dependent upregulation of PMCA4a mRNA. Treatment with the phosphoinositide 3-kinase inhibitor wortmannin produced concentration-dependent inhibition of both PMCA4a upregulation and [3H]thymidine incorporation. These findings suggest a role for phosphoinositide 3-kinase in regulating PMCA expression, which may be important in the control of Ca2+-sensitive VSMC functions.

Clostridium novyi-NT targets aberrant tumor physiology and can produce a precise, robust, and reproducible antitumor response.