Pluto Bioinformatics

GSE71491: RNA-seq analysis of immunogenic actions of metronomic cyclophosphamide treatment: dependence of gene responses on tumor model, mouse host, and drug schedule

Bulk RNA sequencing

RNA-seq analysis was performed using RNA isolated from three tumor models (GL261 glioma, LLC Lewis lung carcinoma, B16F10 melanoma) implanted subcutaneousy in C57BL/6 mice, or in ICR scid mice. Mice were untreated or were treated with cyclophosphamide (CPA) given on a 6-day repeating metronomic schedule (CPA/6d), except as noted. Results from these global transcriptome analysis indicated substantial elevation of basal GL261 immune infiltration and strong activation by CPA/6d treatment of GL261 immune stimulatory pathways and their upstream regulators, but without preferential depletion of negative immune regulators compared to LLC and B16F10 tumors. In LLC tumors, where CPA/6d treatment was found to be anti-angiogenic, CPA/6d suppressed VEGFA target genes and down regulated cell adhesion and leukocyte transendothelial migration genes. In GL261 tumors implanted in adaptive immune-deficient scid mice, where CPA/6d-induced GL261 regression is incomplete and late tumor growth rebound can occur, T cell receptor signaling and certain cytokine-cytokine receptor responses seen in B6 mice were deficient. Extending the CPA treatment interval from 6 to 9 days (CPA/9d) which results in a strong but transient natural killer cell response followed by early tumor growth rebound induced fewer cytokines and increased expression of drug metabolism genes. Taken together, these findings elucidate molecular response pathways activated by intermittent metronomic CPA treatment and identify deficiencies that characterize immune-unresponsive tumor models and drug schedules. SOURCE: David,J.,Waxman (djw@bu.edu) - Boston University