NKG2A and HLA-E define an alternative immune checkpoint axis in bladder cancer

Programmed cell death protein 1 (PD-1)/programmed death-ligand 1 (PD-L1)-blockade immunotherapies have limited efficacy in the treatment of bladder cancer. Here, we show that NKG2A associates with improved survival and responsiveness to PD-L1 blockade immunotherapy in bladder tumors that have high abundance of CD8+ T cells. In bladder tumors, NKG2A is acquired on CD8+ T cells later than PD-1 as well as other well-established immune checkpoints. NKG2A+ PD-1+ CD8+ T cells diverge from classically defined exhausted T cells through their ability to react to human leukocyte antigen (HLA) class I-deficient tumors using T cell receptor (TCR)-independent innate-like mechanisms. HLA-ABC expression by bladder tumors is progressively diminished as disease progresses, framing the importance of targeting TCR-independent anti-tumor functions. Notably, NKG2A+ CD8+ T cells are inhibited when HLA-E is expressed by tumors and partly restored upon NKG2A blockade in an HLA-E-dependent manner. Overall, our study provides a framework for subsequent clinical trials combining NKG2A blockade with other T cell-targeted immunotherapies, where tumors express higher levels of HLA-E.

Preclinical studies of the anti-tumor effects of novel Avian paramyxovirus 4 (APMV-4) oncolytic viral therapy combined with vascular endothelial growth factor-C (VEGF-C) in melanoma

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Background: Avian paramyxoviruses (APMVs) are negative-sense, single-stranded RNA viruses, of which best known is APMV-1, commonly referred to as Newcastle disease virus (NDV). NDV has been extensively studied as an oncolytic virus (OV) and has been shown to be a promising viral agent for human cancer therapy. We identified APMV-4 as a novel OV from the APMV family, with several advantages over NDV and other classes of OVs. APMV-4 is selective for cancer cells, it is not a human pathogen, there is no pre-existing immunity to this virus in humans, and it can be engineered to deliver various therapeutics. Here, we investigated anti-tumor properties of APMV-4 in mouse tumor models, and the role of Vascular Endothelial Growth Factor-C (VEGF-C), a key lymphangiogenesis factor, on therapeutic effects of AMPV-4. Methods: Anti-tumor effects of OVs were assessed using B16F10 melanoma and CT26.WT colon carcinoma in syngeneic mouse models. Tumor cells were injected intradermally into the flank, and treatment commenced when tumors reached ̃50mm3. Viruses were injected intratumorally (107 PFU) every two days, for a total of four treatments. For studies of VEGF-C, B16F10 cells were transfected with VEGF-C or with an empty vector. Tumor regression and long-term survival were assessed. Mice in complete remission were re-challenged with tumor cells on the opposite side. High-dimensional immunophenotyping using Aurora Spectral flow cytometry was performed on tumor samples collected 12 hr after the 2nd treatment with OVs. Results: Intratumoral administration of APMV-4 extended survival, promoted tumor elimination and conferred protection against re-challenge in murine colon carcinoma and melanoma tumor models, and was more effective than NDV strain LaSota. Expression of VEGF-C in B16F10 melanoma enhanced anti-tumor effects of APMV-4 or NDV, resulting in complete remission in 100% and 86% of mice, respectively (n = 7). Mice remained tumor-free during the 90-day observation period, and following re-challenge remained tumor-free for more than a year. Protection from tumor development upon re-challenge was observed in 71% and 83% of mice treated with APMV-4 or NDV, respectively. Results are representative of two experiments. VEGF-C expression in tumors induced lymphangiogenesis, which correlated with high T-cell densities. Analysis of tumor immune cell composition by flow cytometry revealed multiple unique T-cell and NK-cell subsets associated with complete remission. Conclusions: These studies identify APMV-4 as a novel oncolytic agent with great therapeutic potential and VEGF-C as potent enhancer of anti-tumor immunity. High anti-tumor efficacy of APMV-4/VEGF-C monotherapy, that in preclinical models leads to tumor eradication, indicates great therapeutic and vaccine potential of APMV-4 when combined with VEGF-C.

High endogenous CCL2 expression promotes the aggressive phenotype of human inflammatory breast cancer

Inflammatory Breast Cancer (IBC) is a highly aggressive malignancy with distinct clinical and histopathological features whose molecular basis is unresolved. Here we describe a human IBC cell line, A3250, that recapitulates key IBC features in a mouse xenograft model, including skin erythema, diffuse tumor growth, dermal lymphatic invasion, and extensive metastases. A3250 cells express very high levels of the CCL2 chemokine and induce tumors enriched in macrophages. CCL2 knockdown leads to a striking reduction in macrophage densities, tumor proliferation, skin erythema, and metastasis. These results establish IBC-derived CCL2 as a key factor driving macrophage expansion, and indirectly tumor growth, with transcriptomic analysis demonstrating the activation of multiple inflammatory pathways. Finally, primary human IBCs exhibit macrophage infiltration and an enriched macrophage RNA signature. Thus, this human IBC model provides insight into the distinctive biology of IBC, and highlights potential therapeutic approaches to this deadly disease.

Inflammatory breast cancer (IBC) is an aggressive form of breast cancer with a poor prognosis. Here the authors report the characterization of a human IBC cell line recapitulating the clinical and histopathological features of the human disease, and implicating its high level of CCL2 in macrophage infiltration and tumor progression.

Treatment of locally advanced esophageal carcinoma with induction cisplatin-paclitaxel-5FU (PTF) before local therapy

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Background: We analyse induction therapy with PTF before local definitive therapy in terms of response, resectability, toxicity and survival. Methods: Patients (pts) with locally advanced esophageal carcinoma were included. Treatment: Paclitaxel 175 mg/m2 and CDDP 75 mg/m2 on day 1 and 5FU 800 mg/m2/day, days 1–4, every 21 days. After 2–3 cycles surgery is considered. If unresectable, Radiotherapy (64 Gy) and concomitant Carboplatin (60 mg/m2, d 1–5 during 1st and 4th week of RT) are planned. Results: From May-02 to October-06 31 pts were treated (28M, 3F) Age: 55 (32–70) PS 0–1: 6–25. Location: Upper 10, Middle 13, Distal 7, Whole 1. Pathology: Squamous 29, Adenocarcinoma 2. T3/4:14/17 N0/1:8/23 M1a: 3. Weight loss >10 kg 12 pts. 87 cycles have been delivered. Range: 2–4. Mean 2,83. Median 3. Toxicity (episodes): hematological 3/4: no episodes. Emesis 3: 2. Mucositis 3: 2. Asthenia 2/3: 8. 2 pts died in remission due to gastrostomy complications and esophago-tracheal fistula, treatment related. Response: CR 5, PR 9, SD 13, PD 4. Treatment after PTF: Surgery 10 pts (1 upper, 5 middle, 4 distal). 1 distal unresectable at surgery, 2 middle not resected because of liver cirrhosis and liver metastases at surgery. pCR: 1. pPR 6 (R0: 3, R1: 3) Chemoradiation with concomitant Carboplatin: 19, making 3 SD in PR, 2 PR in CR and 1 SD in CR. One PR and 4 SD progressed after chemoradiation. Progression: 21 (local 7, systemic 7, both 7). Died: 19 (16 of disease, 2 of complications of gastrostomy, 1 unrelated) Median PFS: 48,28 weeks (95% CI 32,80 - 63,77). Median OS: 51,14 weeks (95% CI 28,81 - 73,47). Conclusions: This schedule has a good toxicity profile. Surgical rescue is possible in almost a half of middle and distal tumours. Chemoradiation is the best approach for unresectable tumours. Considering stage at diagnosis, survival curves are promising.

No significant financial relationships to disclose.

Nasopharyngeal carcinoma: Comparison of concomitant chemoradiotherapy with neoadjuvant chemotherapy in the caucasian population

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Background: Nowadays, concomitant chemoradiotherapy (CT-RT) is the standard treatment for nasopharyngeal carcinoma (NPC). Neoadyuvant chemotherapy (CT) has been investigated without definitive conclusions. The aim of this study is to compare results of patients(pts) treated with neoadyuvant CT with those treated with concurrent CT-RT. Methods: 38 pts with histologically proven NPC stage II-IVb (PS 0–2) were treated. 27 pts (71.1%) (Group A) (June 1994-May 2000) received Cisplatin (P) 100 mg/m2, Epirrubicin (E) 70 mg/m2, Bleomicin (B) 15 mg D1 and B 12 mg/m2 continous infusion (c.i) for 5 days every 3 week with sequential RT. The other 11 pts (28.9%) (Group B) (June 2002-August 2006) received P 100 mg/m2 D1, D22 and D43 concurrent with RT followed by adyuvant CT P 80 mg/m2 and 5-Fluorouracil 1,000mg/m2/d D1-D4 c.i every 28 day for 3 cycles. Results: 38 pts: 30 male(79%), 8 female(21%). Median age: 53(range 15–75). Stages:II:7, III:11, IVA:12, IVB:8(AJCC 2002). Histology:WHO I-II:11, WHO III:27. Overall response rate: Group A: 25/27 (92.5%), Group B: 10/11 (90.9%) p=0.65. Group A: CR: 17/27 (62.9%); PR: 8/27 (29.6%); PD: 1/27( 3.7%). Group B: CR: 8/11(72.7%); RP: 2/11 (18.1%). 1 pts of each group was not evaluated. Median overall survival (OS) was 34 months (m) in Group A and has not been reached in Group B. Estimated 3 years OS was 48% in GroupA and 80% in GroupB. Median progression free survival (PFS) was 42 m in Group A and 45 m in Group B p=0.72. Estimated 3 years PFS was 50.6% and 66.7% respectively. In the multivariate analysis concurrent CT-RT (HR=5.94 p=0.03) and stage (HR=0.17 p=0.01) were associated with OS. There was 2 toxic death in Group A. The most common toxicities was; Group A: bone marrow suppresion, nausea; Group B: mucositis. Conclusions: These data suggest that P based concomitant CT-RT improves OS and PFS compared with neoadyuvant CT (BEC) followed by RT.

No significant financial relationships to disclose.