Breast cancer cells that preferentially metastasize to lung or bone are more glycolytic, synthesize serine at greater rates, and consume less ATP and NADPH than parent MDA-MB-231 cells.

Gene expression signatures associated with breast cancer metastases suggest that metabolic re-wiring is important for metastatic growth in lungs, bones, and other organs. However, since pathway fluxes depend on additional factors such as ATP demand, allosteric effects, and post-translational modification, flux analysis is necessary to conclusively establish phenotypes. In this study, the metabolic phenotypes of breast cancer cell lines with low (T47D) or high (MDA-MB-231) metastatic potential, as well as lung (LM)- and bone (BoM)-homing lines derived from MDA-MB-231 cells, were assessed by 13C metabolite labeling from [1,2-13C] glucose or [5-13C] glutamine and the rates of nutrient and oxygen consumption and lactate production. MDA-MB-231 and T47D cells produced 55 and 63%, respectively, of ATP from oxidative phosphorylation, whereas LM and BoM cells were more glycolytic, deriving only 20-25% of their ATP from mitochondria. ATP demand by BoM and LM cells was approximately half the rate of the parent cells. Of the anabolic fluxes assessed, nucleotide synthesis was the major ATP consumer for all cell lines. Glycolytic NADH production by LM cells exceeded the rate at which it could be oxidized by mitochondria, suggesting that the malate-aspartate shuttle was not involved in re-oxidation of these reducing equivalents. Serine synthesis was undetectable in MDA-MB-231 cells, whereas 3-5% of glucose was shunted to serine by LM and BoM lines. Proliferation rates of T47D, BoM, and LM lines tightly correlated with their respiration-normalized NADPH production rates. In contrast, MDA-MB-231 cells produced NADPH and GSH at higher rates, suggesting this line is more oxidatively stressed. Approximately half to two-thirds of NADPH produced by T47D, MDA-MB-231, and BoM cells was from the oxidative PPP, whereas the majority in LM cells was from the folate cycle. All four cell lines used the non-oxidative PPP to produce pentose phosphates, although this was most prominent for LM cells. Taken together, the metabolic phenotypes of LM and BoM lines differed from the parent line and from each other, supporting the metabolic re-wiring hypothesis as a feature of metastasis to lung and bone.

Rosai-Dorfman Disease of the Chest Wall Following Mastectomy for Breast Cancer.

Rosai-Dorfman disease (RDD) is a rare benign proliferative histiocytic disorder generally affecting the cervical lymph nodes as sinus histiocytosis with massive lymphadenopathy. We present a unique case of multifocal soft tissue RDD originating from previous mastectomy site and retroperitoneum. The patient is a 62-year-old African American female with a prior history of bilateral breast invasive ductal adenocarcinoma. 2 years following completion of therapy, our patient re-presented with an abdominal wall mass. The core biopsy was discordant, and the mass had rapid growth prompting excision. After the excision of the abdominal wall mass pathology confirmed RDD. A PET confirmed a solitary mass behind the left kidney this mass was biopsied and confirmed that it was RDD in the retroperitoneum. Due to the slow growth of this mass observation was deemed reasonable. We present this case to highlight the need for further research to improve treatment guidelines and expectations.