Low Infiltration Group Research Articles

Immunogenic tumor cell death induced by chemotherapy in patients with breast cancer and esophageal squamous cell carcinoma.

It has been reported that chemo-radiotherapy can induce immunogenic tumor cell death (ICD), which triggers T-cell immunity mainly mediated by high-mobility group box 1 protein (HMGB1) and calreticulin. However, there is still limited information to support this theory relating to chemotherapy alone. In the present study, the expression of HMGB1 and calreticulin was evaluated by immunohistochemistry in pre-treatment biopsy specimens and surgically resected specimens, which were obtained from patients with breast cancer (n=52) and esophageal squamous cell carcinoma (ESCC) (n=8) who had been treated with neoadjuvant chemotherapy (NAC). We also analyzed HMGB1 and calreticulin expression in breast cancer cell lines treated with chemotherapeutic drugs. As a result, both HMGB1 and calreticulin expression levels were significantly upregulated after NAC in both breast cancer and ESCC tissues. However, no significant correlation was observed between HMGB1 expression and pathological response after NAC or between HMGB1 expression and patient survival. Furthermore, although overall survival in the high infiltration group of CD8-positive T cells was significantly superior to that in the low infiltration group in breast cancer patients, there were no correlations between the number of CD8-positive T cells and HMGB1 or calreticulin expression levels. In addition, chemotherapeutic drugs induced upregulation of HMGB1 and calreticulin in all tested cell lines. Our findings indicate that chemotherapy alone can significantly induce ICD regardless of the degree of pathological response after chemotherapy.

Abstract 2945: Impact of intratumoral mature dendritic cells on prognosis of the patients with esophageal squamous cell carcinoma

Abstract [Background] Promising efficacy of the immunotherapy with anti-PD-1 antibody for esophageal squamous cell carcinoma (ESCC) is expected. Tumor-infiltrating lymphocytes (TILs)have been found to be associated with favorable outcome of patients in many cancers including ESCC. However, the contributing factor of TILs in the primary tumor remains unclear. Dendritic cells (DCs) are the most potent antigen-presenting cells to induce cytotoxic T lymphocytes. [Purpose] The aim of this study was to examine the correlation of mature dendritic cells with CD8+ cells in the tumor in order to clarify the impact of DCs on locally infiltrated lymphocytes in ESCC. [Object and Methods] Formalin-fixed, paraffin-embedded blocks of primary lesions were collected from 80 patients with ESCC who underwent surgical treatment at Osaka City University Hospital. Immunohistochemical analysis using anti-LAMP-3 antibody and CD8 antibody was used to evaluate intratumoral DCs and TILs. The number of LAMP-3+DCs and TILs were counted at ×400 magnification. We divided the 80 cases into two groups according to the median number of intratumoral DCs and TILs to examine the clinicopathological features. [Results] LAMP-3+DCs were predominantly observed in peritumoral area and sparsely found in intratumoral area, whereas CD8+T cells distributed between both peritumoral and intratumoral areas. The number of DCs was significantly associated with increasing TNM stage. For example, the median number of DCs was 59.9 in pathological T1, 34.2 in T2/3, 62.4 in pN1, 34.1 in pN1/2/3. In addition, many patients with high infiltaraion of DCs had positive lymphatic invasion (Ly). The number of intratumoral DCs was significantly correlated with the number of TILs which were observed in intratumoral regions. Patients in the high infiltration of DCs group showed a significant better prognosis than patients in the low infiltration group. Double staining showed that LAMP3+DC-CD8+T cell clusters were seen in peritumoral area. Citation Format: Junya Nishimura, Hiroaki Tanaka, Yuichiro Miki, Tatsuro Tamura, Tatsunari Fukuoka, Go Ohira, Masatsune Shibutani, Sadaaki Yamazoe, Kenjiro Kimura, Takahiro Toyokawa, Hisashi Nagahara, Ryosuke Amano, Kazuya Muguruma, Kiyoshi Maeda, Kosei Hirakawa, Masaichi Ohira. Impact of intratumoral mature dendritic cells on prognosis of the patients with esophageal squamous cell carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2945. doi:10.1158/1538-7445.AM2017-2945

Abstract 4075: Composition and distribution of tumor-infiltrating lymphocytes in breast cancer

Abstract Backgroud: High tumor-infiltrating lymphocytes(TILs)are known to be associated with response to primary systemic therapy (PST) in breast cancer patients especially in Her2+ and triple negative patients. However, the composition of TILs in the high infiltration group is largely unknown. Uncovering the immunodynamic composition of TILs may be useful for better understanding the mechanism how the TILs exert effect. And the immune reservoir data for extensive analysis of altered TIL subsets after chemotherapy is still lacking. Methods: The tumor specimens of 56 breast cancer patients who did not receive PST and 16 breast cancer patients who underwent surgical resection after anthracycline- or anthracycline/taxane-based PST were analysed. We used the multi -parametric flow cytometric platform (optimized for 20 colors for each panel of T cells, B cells, NK, and other Lineage markers detection) to accomplish the purpose. The result is more objective and estimated parameter is more abundant compared to the histological methods (hematoxylin-eosin staining and immunohistochemical staining). Breast cancer patients can be divided into low, medium and high infiltration group according to the CD45+ number in the tissue and weight of the tumor specimens. TIL subset composition is compared among different groups (Low vs Medium vs High, Chemotherapy vs non Chemotherapy). Result: In patients with ER- and high histological grade patients, there are more TILs infiltration compared to the ER+ and low histological grade patients (P = 0.038 and P = 0.039 respectively). And we found that the percentage of CD4+T cells in total CD3+T cells, Treg in CD4+T cells and Plasmablasts in total B cells is much higher in the high infiltration group compared to the low infiltration group (56.03% vs 44.21%, P<0.01; 18.64% vs 9.37%, P<0.001; 16.75% vs 1.88%, P<0.001 respectively). By contrast, percentage of CD8+T in total CD3+T cells and NK cells in the total lymphocytes is much lower (35.26% vs 46.71%, P<0.001; 2.74% vs 5.88%, P<0.01 respectively). After PST both the percentage of CD8+T in total CD3+T cells and effector memory CD8+T cells increase heavily (53.82% vs 41.14%, P<0.001; 79.49% vs70.88%, P<0.05 respectively) and percentage of CD4+T cells in total CD3+T and naïve CD8+T cells decrease (31.81% vs 50.35%, P<0.001; 2.81% vs 4.21%, P<0.05 respectively). Functional markers such as HLADR,CD28 and PD1 in the T cells decrease dramatically and CD127 increases noticeably. Conclusion: The inner composition of TIL subsets in the high infiltration is largely different from low infiltration group and this might help explain the reason why high TILs could predict pathological complete response. Chemotherapy can lead to the heavy change of TIL subsets and this may be the part of immunological mechanism that why chemotherapy has deep influences on the tumor. Citation Format: Liang Guo, Yayun Chi, Jingyan Xue, Shyamal Goswami, Bingqing Zhou, Chunmei Cao, Zhimin Shao, Xiaoming Zhang, Jiong Wu. Composition and distribution of tumor-infiltrating lymphocytes in breast cancer. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 4075.