In triple-negative breast cancer (TNBC), the benefit of combining chemotherapy with checkpoint inhibitors is still not very clear. We utilize single-cell RNA- and ATAC-sequencing to examine the immune cell dynamics in 22 patients with advanced TNBC treated with paclitaxel or its combination with the anti-PD-L1 atezolizumab. We demonstrate that high levels of baseline CXCL13⁺ T cells are linked to the proinflammatory features of macrophages and can predict effective responses to the combination therapy. In responsive patients, lymphoid tissue inducer (LTi) cells, follicular B (Bfoc) cells, CXCL13⁺ T cells, and conventional type 1 dendritic cells (cDC1) concertedly increase following the combination therapy, but instead decrease after paclitaxel monotherapy. Our data highlight the importance of CXCL13⁺ T cells in effective responses to anti-PD-L1 therapies and suggest that their reduction by paclitaxel regimen may compromise the clinical outcomes of accompanying atezolizumab for TNBC treatment.

Purpose: The current management of advanced esophageal squamous cell carcinoma (ESCC) remains unsatisfactory. We investigated the safety, efficacy, and biomarkers of SHR-1210, an anti-PD-1 antibody, in patients with recurrent or metastatic ESCC. Experimental Design: This study was part of a phase I trial in China. Patients with advanced ESCC who were refractory or intolerant to previous chemotherapy were enrolled. Eligible patients received intravenous SHR-1210 at a dose of 60 mg, with escalation to 200 and 400 mg (4-week interval after first dose followed by a 2-week schedule) until disease progression or intolerable toxicity. The associations between candidate biomarkers (PD-L1 and somatic mutation load) and the efficacy of SHR-1210 were also explored. Results: Between May 11, 2016, and December 9, 2016, a total of 30 patients from one site in China were enrolled. Ten patients (33.3%) had an independently assessed objective response. Median progression-free survival was 3.6 months (95% CI, 0–7.2). Three (10.0%) treatment-related grade 3 adverse events were reported: two (6.7%) pneumonitis and one (3.3%) increased cardiac troponin I. No grade 4 or grade 5 treatment-related adverse events were reported. The exome sequencing and analysis showed that the mutational burden and the potential mutation-associated neoantigen count were associated with better responses. An objective response was more common in patients with PD-L1–positive tumors as defined by ≥5% staining (7 of 15 patients) than in those with PD-L1–negative tumors (1 of 9 patients). Conclusions: In this population of ESCC patients, SHR-1210 had a manageable safety profile and promising antitumor activity. Clin Cancer Res; 24(6); 1296–304. ©2018 AACR.

MET encodes a receptor tyrosine kinase c‐MET for hepatocyte growth factor (HGF). The specific combination of c‐MET and HGF activates downstream signaling pathways to trigger cell migration, proliferation, and angiogenesis. MET exon 14 alterations and MET gene amplification play a critical role in the origin of cancer. Several monoclonal antibodies and small‐molecule inhibitors of c‐MET have been evaluated in clinical trials. In patients with advanced non‐small cell lung cancer, cabozantinib and crizotinib showed clear efficacy with a generally tolerable adverse events profile. In gastrointestinal cancers, most phase III trials of MET inhibitors showed negative results. In hepatocellular carcinoma, based on the encouraging results of some phase II studies, a series of phase III trials are currently recruiting patients to access the efficacy and safety of MET inhibitors.

To assess the safety profile, pharmacokinetics, pharmacodynamics and preliminary antitumour activity of fixed-dose SHR-1210, a novel anti-PD-1 antibody, in advanced solid tumours. A total of 36 patients with advanced solid tumours received intravenous SHR-1210 at 60 mg, 200 mg and 400 mg (4-week interval after first dose followed by a 2-week schedule) until disease progression or intolerable toxicity. The concentration of SHR-1210 was detected for pharmacokinetics, and receptor occupancy on circulating T lymphocytes was assessed for pharmacodynamics. No dose-limiting toxicities were observed. Maximum administered dose was not reached. Most adverse events were grade 1 or 2. Treatment-related severe adverse events were found in two patients. No treatment-related death was reported. Two complete responses (gastric cancer, bladder carcinoma) and seven partial responses were seen. In responders, the median follow-up time was 16.0 months (range 8.3–19.5), and the median duration of response was not reached (range 2.7–17.5+ months). The half-life of SHR-1210 was 2.94 d, 5.61 d and 11.0 d for 3 dose levels, respectively. Our results demonstrated a promising antitumour activity and a manageable safety profile of SHR-1210, displayed an explicit PK evidence of the feasibility of fixed dose, and established the foundation for further exploration.

Better pathologic complete response and relapse-free survival after carboplatin plus paclitaxel compared with epirubicin plus paclitaxel as neoadjuvant chemotherapy for locally advanced triple-negative breast cancer: a randomized phase 2 trial

Background: Triple negative breast cancer (TNBC), the most aggressive subtype of breast cancer, is characterized by a high incidence of brain metastasis (BrM) and a poor prognosis. As the most lethal form of breast cancer, BrM remains a major clinical challenge due to its rising incidence and lack of effective treatment strategies. Recent evidence suggested a potential role of lipid metabolic reprogramming in breast cancer brain metastasis (BCBrM), but the underlying mechanisms are far from being fully elucidated. Methods: Through analysis of BCBrM transcriptome data from mice and patients, and immunohistochemical validation on patient tissues, we identified and verified the specific down-regulation of retinoic acid receptor responder 2 (RARRES2), a multifunctional adipokine and chemokine, in BrM of TNBC. We investigated the effect of aberrant RARRES2 expression of BrM in both in vitro and in vivo studies. Key signaling pathway components were evaluated using multi-omics approaches. Lipidomics were performed to elucidate the regulation of lipid metabolic reprogramming of RARRES2. Results: We found that down-regulation of RARRES2 is specifically associated with BCBrM, and that RARRES2 deficiency promoted BCBrM through lipid metabolic reprogramming. Mechanistically, reduced expression of RARRES2 in brain metastatic potential TNBC cells resulted in increased levels of glycerophospholipid and decreased levels of triacylglycerols by regulating phosphatase and tensin homologue (PTEN)-mammalian target of rapamycin (mTOR)-sterol regulatory element-binding protein 1 (SREBP1) signaling pathway to facilitate the survival of breast cancer cells in the unique brain microenvironment. Conclusions: Our work uncovers an essential role of RARRES2 in linking lipid metabolic reprogramming and the development of BrM. RARRES2-dependent metabolic functions may serve as potential biomarkers or therapeutic targets for BCBrM.