Improved Natural Killer cell activity and retained anti-tumor CD8(+) T cell responses contribute to the induction of a pathological complete response in HER2-positive breast cancer patients undergoing neoadjuvant chemotherapy.

BACKGROUND: Locally advanced HER2-overexpressing breast cancer (BC) patients achieve a high rate of pathological complete responses (pCR) after neoadjuvant chemotherapy (NC). The apparently unaltered immune proficiency of these patients together with the immune-modulating activities of NC drugs suggest a potential contribution of host immunity in mediating clinical responses. We thus performed an extensive immunomonitoring in locally advanced BC patients undergoing NC to identify immunological correlates of pCR induction. METHODS: The immune profile of 40 HER2-positive and 38 HER2-negative BC patients was characterized at diagnosis and throughout NC (Paclitaxel and Trastuzumab, or Docetaxel and Epirubicin, respectively). The percentages of circulating immune cell subsets including T and B lymphocytes, Natural Killer (NK) cells, regulatory T cells, T helper 17 lymphocytes, were quantified by multiparametric flow cytometry. NK cells functional activity was evaluated through the analysis of NF-kB nuclear translocation by Multispectral flow cytometry, and with the in vitro monitoring of Trastuzumab-mediated antibody-dependent cell cytotoxicity (ADCC). CD8(+) T cell responses against six different tumor-associated antigens (TAA) were characterized by IFN-γ ELISPOT and IFN-γ/IL-2 DualSpot assays. RESULTS: After NC, HER2-positive patients showed a significant increase in the number of NK cells and regulatory T cells irrespective of the pathological response, whereas patients undergoing a pCR disclosed higher percentages of T helper 17 cells. Notably, a significant increase in the number of activated NK cells was observed only in HER2-positive patients achieving a pCR. Characterization of anti-tumor T cell responses highlighted sustained levels of CD8(+) T cells specific for survivin and mammaglobin-A throughout NC in patients undergoing a pCR in both arms. Moreover, HER2-positive patients achieving a pCR were characterized by a multi-epitopic and polyfunctional anti-tumor T cell response, markedly reduced in case of partial response. CONCLUSIONS: These results indicate that maintenance of functional T cell responses against selected antigens and improvement of NK cell proficiency during NC are probably critical requirements for pCR induction, especially in HER2-positive BC patients. Trail registration: TRIAL REGISTRATION NUMBER: NCT02307227, registered on ClinicalTrials.gov ( http://www.clinicaltrials.gov , November 26, 2014).

Gout-like arthritis following cimetidine and ranitidine.

A case report is presented of a patient having a history of gouty arthritic attacks who suffered similar attacks subsequent to receiving cimetidine and ranitidine. The patient was rechallenged twice with each drug and reacted on each occasion. During the therapy with H2-receptor antagonists, he suffered no attacks that were not immediately preceded by one of these drugs. It is suggested that alternate forms of therapy such as antacids, sucralfate, or carbenoxalone may be preferable in patients suffering from ulcers and gouty arthritic problems.