Myosteatosis evaluation using erector spinae and psoas muscles to predict adverse events during adjuvant chemotherapy for breast cancer.

BACKGROUND: Myosteatosis (intramuscular adiposity) is predictive of chemotherapy toxicity in women undergoing adjuvant chemotherapy for breast cancer (BC). We evaluated a novel, user-friendly and cost-effective technique utilizing a Picture Archiving and Communication Systems (PACS) tool that is readily available in the electronic medical record (EMR), using skeletal muscle density (SMD) to detect myosteatosis and then compared PACS results with those derived from widely used body composition software (SliceOMatic, QC, Canada). METHODS: Using retrospective data from a sample of women with early BC (Stage I-III) who had CT scan and received chemotherapy. Pearson correlation coefficients were used to compare SliceOMatic with PACS results. Associations of PACS results with chemotherapy-related adverse events were evaluated using multivariable (MV) log-binomial models adjusted for age, race, BMI, anthracycline-based therapy, and number of comorbidities. RESULTS: In 338 patients, mean age was 51, 32% were non-white, and 40% had obesity (BMI ≥ 30 kg/m2). Correlation of SMD using SliceOMatic whole muscle measurements with PACS psoas muscle was 0.76 (p < .0001) and with PACS erector spinae muscle 0.91 (p < .0001). Using PACS psoas muscle, myosteatosis was associated with any adverse event [RR 1.66, CI 1.22-2.26 (p < .0001)], dose reduction [RR 1.63, CI 1.01-2.65 (p = .05)], and early treatment discontinuation [RR 2.14, CI 1.10-4.14 (p = 0.03)]. Using PACS erector spinae muscle, myosteatosis was associated any adverse event [RR 1.59, CI 1.11-2.27 (p = 0.01)] and dose reduction [RR 1.91, CI 1.07-3.42 (p = .03)]. CONCLUSION AND RELEVANCE: Skeletal muscle density measures using PACS correlated strongly with SliceOMatic results and both are similarly predictive of chemotherapy-related adverse events.

The histone demethylase KDM4B regulates peritoneal seeding of ovarian cancer.

Epithelial ovarian cancer (EOC) has poor prognosis and rapid recurrence because of widespread dissemination of peritoneal metastases at diagnosis. Multiple pathways contribute to the aggressiveness of ovarian cancer, including hypoxic signaling mechanisms. In this study, we have determined that the hypoxia-inducible histone demethylase KDM4B is expressed in ∼60% of EOC tumors assayed, including primary and matched metastatic tumors. Expression of KDM4B in tumors is positively correlated with expression of the tumor hypoxia marker CA-IX, and is robustly induced in EOC cell lines exposed to hypoxia. KDM4B regulates expression of metastatic genes and pathways, and loss of KDM4B increases H3K9 trimethylation at the promoters of target genes like LOXL2, LCN2 and PDGFB. Suppressing KDM4B inhibits ovarian cancer cell invasion, migration and spheroid formation in vitro. KDM4B also regulates seeding and growth of peritoneal tumors in vivo, where its expression corresponds to hypoxic regions. This is the first demonstration that a Jumonji-domain histone demethylase regulates cellular processes required for peritoneal dissemination of cancer cells, one of the predominant factors affecting prognosis of EOC. The pathways regulated by KDM4B may present novel opportunities to develop combinatorial therapies to improve existing therapies for EOC patients.

ErbB3 upregulation by the HNSCC 3D microenvironment modulates cell survival and growth.

Head and neck squamous carcinomas (HNSCC) present as dense epithelioid three-dimensional (3D) tumor nests that can mediate signals via the human epidermal growth factor receptor (ErbB) tyrosine kinase family to promote intratumoral survival and growth. We examined the role of the tumor microenvironment on ErbB receptor family expression and found that the status of intercellular organization altered the receptor profile. We showed that HNSCC cells forced into tumor island-like 3D aggregates strongly upregulated ErbB3 at the level of transcription. Not only was the elevated ErbB3 responsive to HRG-ß1-induced enhanced signaling mechanism, but also analysis by siRNA-knockdown and kinase inhibitor strategies revealed that the ErbB3/AKT signaling pathway was sufficient to enhance tumor cell survival and growth potential. Elevated ErbB3 expression in the high-density 3D culture system was strongly associated with hypoxia-induced HIF-1α. Hypoxia-regulated ErbB3 expression was mediated by the HIF-1α-binding consensus sequence in the ErbB3 proximal promoter. The findings show that the local 3D tumor microenvironment can trigger reprograming and switching of ErbB family members and thereby influence ErbB3-driven tumor growth.