Programmed death-ligand 1 (PD-L1) and its receptor programmed cell death protein 1 (PD-1) modulate antitumor immunity and are major targets of checkpoint blockade immunotherapy. However, clinical trials of anti-PD-L1 and anti-PD-1 antibodies in breast cancer demonstrate only modest efficacy. Furthermore, specific PD-L1 contributions in various tissue and cell compartments to antitumor immunity remain incompletely elucidated. Here we show that PD-L1 expression is markedly elevated in mature adipocytes versus preadipocytes. Adipocyte PD-L1 prevents anti-PD-L1 antibody from activating important antitumor functions of CD8+ T cells in vitro. Adipocyte PD-L1 ablation obliterates, whereas forced preadipocyte PD-L1 expression confers, these inhibitory effects. Pharmacologic inhibition of adipogenesis selectively reduces PD-L1 expression in mouse adipose tissue and enhances the antitumor efficacy of anti-PD-L1 or anti-PD-1 antibodies in syngeneic mammary tumor models. Our findings provide a previously unappreciated approach to bolster anticancer immunotherapy efficacy and suggest a mechanism for the role of adipose tissue in breast cancer progression.

BackgroundWe explore the clinical and prognostic significance of expression of vascular endothelial growth factor receptor (VEGFR)-2, platelet-derived growth factor receptor (PDGFR)-β, and c-Met in patients with hepatocellular carcinoma (HCC).MethodsThe expression of VEGFR-2, PDGFR-β, and c-Met were determined by immunohistochemical examination of the tissues of 93 HCC patients. The relationships of these markers with clinicopathological factors and prognosis were then analyzed.ResultsHigh expression of VEGFR-2, PDGFR-β, and c-Met was found in 86%, 19.4%, and 80.6% of patients, respectively. Expression of VEGFR-2 correlated with gender (P = 0.044), hepatitis B surface antigen positivity (P = 0.024), degree of tumor differentiation (P = 0.023), and hepatic cirrhosis (P = 0.026). Expression of PDGFR-β correlated with alpha-fetoprotein level (P = 0.029), tumor size (P = 0.033), and hepatic cirrhosis (P = 0.023). No significant correlations were identified between expression of c-Met and clinicopathological factors. Expression of PDGFR-β correlated with overall survival (P = 0.046) and expression of c-Met correlated with progression-free survival (P = 0.01).ConclusionsWe found that in patients with HCC, high expression of VEGFR-2 correlates with chronic hepatitis B virus infection and hepatic cirrhosis. High expression of PDGFR-β is a predictor of poor prognosis. High expression of C-Met may predict therapeutic effectiveness of sorafenib in HCC patients.

BackgroundThe optimal laboratory assay for detecting KRAS mutations in different biospecimens from patients with metastatic colorectal cancer (mCRC), and the clinical relevance of these gene alterations is still in question. We analyzed the prognostic–predictive relevance of KRAS status, determined in tumor and plasma DNA by two different assays, in a large mono-institutional series of mCRC patients.MethodsDNA sequencing and peptide-nucleic-acid-mediated-polymerase chain reaction clamping (PNA-PCR) were used to determine KRAS status in 416 tumor and 242 matched plasma DNA samples from mCRC patients who received chemotherapy only. Relationships with outcomes were analyzed with respect to the different assays and tissue types.ResultsPNA-PCR was significantly more sensitive in detecting KRAS mutations than sequencing (41% vs. 30%, p < 0.001). KRAS mutations were more frequent in tumor tissue than in plasma (sequencing, 38% vs. 17%, p < 0.001; PNA-PCR, 47% vs. 31%, p < 0.001). Median OS was consistently shorter in KRAS-mutated patients than KRAS wild-type patients, independent from the assay and tissue tested; the largest difference was in plasma samples analyzed by PNA-PCR (KRAS mutated vs. wild-type: 15.7 vs. 19.1 months, p = 0.009). No association was observed between KRAS status and other outcomes. When tumor and plasma results were considered together, median OS in patients categorized as tissue/plasma KRAS negative/negative, tissue/plasma KRAS discordant, and tissue/plasma KRAS positive/positive were 21.0, 16.9 and 15.4 months, respectively (p = 0.008).ConclusionsKRAS mutation status is of prognostic relevance in patients with mCRC. KRAS mutations in both tumor tissue and plasma are a strong prognostic marker for poor outcomes.Electronic supplementary materialThe online version of this article (doi:10.1186/s13046-014-0104-7) contains supplementary material, which is available to authorized users.

Immune checkpoint blockade-based immunotherapy has become standard of care for multiple cancer types. However, the overall response rates among various cancer types still remain unsatisfactory. There is a pressing clinical need to identify combination therapies to improve efficacy of anticancer immunotherapy. We previously showed that pharmacologic inhibition of PPARγ by GW9662 boosts αPD-L1 and αPD-1 antibody efficacy in treating murine mammary tumors. In addition, we defined sexually dimorphic αPD-L1 efficacy in B16 melanoma. Here, we show a sexually dimorphic response to the combination of GW9662 and αPD-L1 immunotherapy in B16 melanoma. Combination effects were observed in female, but not male hosts. Neither female oöphorectomy impairs, nor does male castration rescue the combination effects, suggesting a sex hormone-independent response to this combination therapy. In diet-induced obese females, melanoma growth remained responsive to the combination treatment, albeit less robustly than lean females. These findings are informative for future design and application of immunotherapy-related combination therapy for treating human melanoma patients by taking gender and obesity status into consideration.

Objective: To retrospectively assess the size change of hepatic hemangiomas（HH） in hormone receptor positive (HR+) breast cancer patients after comprehensive treatment. Methods: Totally 364 confirmed invasive breast cancer cases with HH were diagnosed at the Breast Cancer Center of Yunnan Cancer Hospital in 2013-2018 by abdominal color Doppler ultrasound (ADUS) + contrast enhanced ultrasound (CEUS) and at least one upper abdominal CT imaging examination. Follow-up was 6-78 months, and changes in location, number and size of HH at different treatment stages were compared between the HR+ and 85 HR- groups. Subgroup analysis of patients receiving chemotherapy and endocrine therapy was also performed. Results: Totally 323 patients were enrolled, including 238 HR+ (73.7%) and 85 HR- (26.3%) cases. Changes in the longest diameter were similar in both groups (P=0.556), and size change of HH was not associated with axillary lymph node metastasis of breast cancer (P>0.05). HH showed no change during chemotherapy but was significantly enlarged after chemotherapy (P<0.01). There was no significant difference between the tamoxifen (TAM; endocrine drug) only and combination or sequential endocrine treatment (P>0.05) groups. Only the aromatase inhibitor group showed statistical significance (P<0.05) in the AI (letrozole, anastrozole and exemestane) group at the t1 time point. Conclusion: During chemotherapy and endocrine therapy for breast cancer patients with HH, the size of HH changes in some patients, while others develop new HH. No significant effect on size change of HH was observed in this study.