A Breast Cancer Tumor's Immune Signature Could Predict Response to Neoadjuvant Therapy

“In a study reported in the Journal of Clinical Oncology, Denkert et al found that increased tumor-infiltrating lymphocytes and the presence of lymphocyte-predominant breast cancer were associated with increased rates of pathologic complete response in patients receiving neoadjuvant anthracycline-taxane treatment with or without carboplatin. Higher rates were observed with carboplatin, with treatment interactions being significant among all patients and among those with HER2-positive disease but not among those with triple-negative disease. mRNA profiles for immune-related genes also distinguished pathologic complete response rates.

“The study involved 580 tumors from patients in the GeparSixto trial, which assessed the effects on pathologic complete response rates of adding carboplatin to neoadjuvant anthracycline plus taxane treatment. The current analysis assessed the effects on pathologic complete response of tumor-infiltrating lymphocyte levels, the presence of lymphocyte–predominant disease, and levels of immune-activating (CXCL9, CCL5, CD8A, CD80, CXCL13, IGKC, CD21) and immunosuppressive genes (IDO1, PD-1, PD-L1, CTLA4, FOXP3).”


Epidermal EGFR Controls Cutaneous Host Defense and Prevents Inflammation

“The epidermal growth factor receptor (EGFR) plays an important role in tissue homeostasis and tumor progression. However, cancer patients treated with EGFR inhibitors (EGFRIs) frequently develop acneiform skin toxicities, which are a strong predictor of a patient’s treatment response. We show that the early inflammatory infiltrate of the skin rash induced by EGFRI is dominated by dendritic cells, macrophages, granulocytes, mast cells, and T cells. EGFRIs induce the expression of chemokines (CCL2, CCL5, CCL27, and CXCL14) in epidermal keratinocytes and impair the production of antimicrobial peptides and skin barrier proteins. Correspondingly, EGFRI-treated keratinocytes facilitate lymphocyte recruitment but show a considerably reduced cytotoxic activity against Staphylococcus aureus. Mice lacking epidermal EGFR (EGFRΔep) show a similar phenotype, which is accompanied by chemokine-driven skin inflammation, hair follicle degeneration, decreased host defense, and deficient skin barrier function, as well as early lethality. Skin toxicities were not ameliorated in a Rag2-, MyD88-, and CCL2-deficient background or in mice lacking epidermal Langerhans cells. The skin phenotype was also not rescued in a hairless (hr/hr) background, demonstrating that skin inflammation is not induced by hair follicle degeneration. Treatment with mast cell inhibitors reduced the immigration of T cells, suggesting that mast cells play a role in the EGFRI-mediated skin pathology. Our findings demonstrate that EGFR signaling in keratinocytes regulates key factors involved in skin inflammation, barrier function, and innate host defense, providing insights into the mechanisms underlying EGFRI-induced skin pathologies.”