The present invention advantageously provides for novel gene signatures, tools and methods for the treatment and prognosis of epithelial tumors. Applicants have used single cell RNA-seq to reveal novel expression programs of malignant, stromal and immune cells in the HNSCC tumor ecosystem. Malignant cells varied in expression of programs related to stress, hypoxia and epithelial differentiation. A partial EMT-like program (p-EMT) was discovered that was expressed in cells residing at the leading edge of tumors. Applicants unexpectedly linked the p-EMT state to metastasis and adverse clinical features that may be used to direct treatment of epithelial cancers (e.g., HNSCC). Applicants also show that metastases are dynamically regulated by the tumor microenvironment (TME). Finally, a computational modeling approach was developed that allows analysis of malignant cells in bulk sequencing samples.