Detection of Specific Immune Cell Subpopulation Changes Associated with Systemic Immune Inflammation-Index Level in Germ Cell Tumors.

The tumor microenvironment (TME) and the host inflammatory response are closely interconnected. The interplay between systemic inflammation and the local immune response may influence tumor development and progression in various types of cancer. The systemic immune-inflammation index (SII) represents a prognostic marker for germ cell tumors (GCTs). The aim of the present study was to detect specific immune cell subpopulation changes which were associated with the SII level in chemotherapy-naïve GCT patients. In total, 51 GCT patients, prior to cisplatin-based chemotherapy, were included in the present study. Immunophenotyping of peripheral blood leukocyte subpopulations was performed using flow cytometry. The SII level was correlated with the percentage of various leukocyte subpopulations. The obtained results demonstrated that SII levels above the cut-off value of SII ≥ 1003 were associated with higher neutrophil percentages. An inverse correlation was found between the SII and the peripheral lymphocyte percentage that logically reflects the calculations of the SII index. Furthermore, the presented data also showed that in the lymphocyte subpopulation, the association with the SII was driven by T-cell subpopulations. In innate immunity-cell subpopulations, we observed a correlation between SII level and neutrophils as well as associations with eosinophil, basophil, natural killer cell and dendritic cell percentages. We suppose that the described interactions represent a manifestation of cancer-induced immune suppression. The results of the present study contribute to the elucidation of the interrelationship between tumor cells and the innate/adaptive immune system of the host.

Comprehensive Assessment of Selected Immune Cell Subpopulations Changes in Chemotherapy-Naïve Germ Cell Tumor Patients.

The pattern of immune cell distribution in testicular germ cell tumors (GCT) significantly differs from the immune environment in normal testicular tissues. The present study aimed to evaluate the role of different leukocyte subpopulation in GCTs. A cohort of 84 chemotherapy-naïve GCT patients was analyzed. Immunophenotyping of peripheral blood leukocyte subpopulations was carried out by flow cytometry. In addition, the data assessing the immunophenotypes and the baseline clinicopathological characteristics of the included subjects were statistically evaluated. Their prognostic value for the assessment of progression-free survival (PFS) and overall survival (OS) was estimated. The percentage of different innate/adaptive immune cell subpopulations was significantly associated with poor risk-related clinical features, including the number of metastatic sites, presence of retroperitoneal, mediastinal, lung, brain and non-pulmonary visceral metastases as well as with the S-stage and International Germ Cell Consensus Classification Group (IGCCCG) risk groups. In univariate analysis, the percentages of neutrophils, eosinophils, dendritic cells type 2, lymphocytes and T cytotoxic cells were significantly associated with PFS, while the neutrophil, non-classical monocyte and lymphocyte percentage were associated with OS. However, all these outcome correlations were not independent of IGCCCG in multivariate analysis. The data indicated a link among different innate/adaptive peripheral immune cell subpopulations in GCT patients. In addition, the association between these subpopulations and tumor characteristics was also investigated. The findings of the present study may contribute to a deeper understanding of the interactions between cancer and innate/adaptive immune response in GCT patients.

Are Changes in the Percentage of Specific Leukocyte Subpopulations Associated with Endogenous DNA Damage Levels in Testicular Cancer Patients?

Chemoresistance of germ cell tumors (GCTs) represents an intensively studied property of GCTs that is the result of a complicated multifactorial process. One of the driving factors in this process is the tumor microenvironment (TME). Intensive crosstalk between the DNA damage/DNA repair pathways and the TME has already been reported. This study aimed at evaluating the interplay between the immune TME and endogenous DNA damage levels in GCT patients. A cocultivation system consisting of peripheral blood mononuclear cells (PBMCs) from healthy donors and GCT cell lines was used in an in vitro study. The patient cohort included 74 chemotherapy-naïve GCT patients. Endogenous DNA damage levels were measured by comet assay. Immunophenotyping of leukocyte subpopulations was performed using flow cytometry. Statistical analysis included data assessing immunophenotypes, DNA damage levels and clinicopathological characteristics of enrolled patients. The DNA damage level in PBMCs cocultivated with cisplatin (CDDP)-resistant GCT cell lines was significantly higher than in PBMCs cocultivated with their sensitive counterparts. In GCT patients, endogenous DNA damage levels above the cutoff value were independently associated with increased percentages of natural killer cells, CD16-positive dendritic cells and regulatory T cells. The crosstalk between the endogenous DNA damage level and specific changes in the immune TME reflected in the blood of GCT patients was revealed. The obtained data contribute to a deeper understanding of ongoing interactions in the TME of GCTs.

Disulfiram Overcomes Cisplatin Resistance in Human Embryonal Carcinoma Cells.

Cisplatin resistance in testicular germ cell tumors (TGCTs) is a clinical challenge. We investigated the underlying mechanisms associated with cancer stem cell (CSC) markers and modalities circumventing the chemoresistance. Chemoresistant models (designated as CisR) of human embryonal carcinoma cell lines NTERA-2 and NCCIT were derived and characterized using flow cytometry, gene expression, functional and protein arrays. Tumorigenicity was determined on immunodeficient mouse model. Disulfiram was used to examine chemosensitization of resistant cells. ALDH1A3 isoform expression was evaluated by immunohistochemistry in 216 patients' tissue samples. Chemoresistant cells were significantly more resistant to cisplatin, carboplatin and oxaliplatin compared to parental cells. NTERA-2 CisR cells exhibited altered morphology and increased tumorigenicity. High ALDH1A3 expression and increased ALDH activity were detected in both refractory cell lines. Disulfiram in combination with cisplatin showed synergy for NTERA-2 CisR and NCCIT CisR cells and inhibited growth of NTERA-2 CisR xenografts. Significantly higher ALDH1A3 expression was detected in TGCTs patients' tissue samples compared to normal testicular tissue. We characterized novel clinically relevant model of chemoresistant TGCTs, for the first time identified the ALDH1A3 as a therapeutic target in TGCTs and more importantly, showed that disulfiram represents a viable treatment option for refractory TGCTs.

ßcatenin is a marker of poor clinical characteristics and suppressed immune infiltration in testicular germ cell tumors.

BACKGROUND: WNT/ßcatenin (WNTß) pathway is activated in early stages of embryonic development. We aimed to evaluate the significance of ßcatenin in germ cell tumors (GCTs) and explore associations with the inflamed environment. METHODS: Surgical specimens from 247 patients were analyzed. Βcatenin expression was detected in the tumor tissue by immunohistochemistry and correlated with clinical characteristics, outcome, PD-L1 expression and systemic immune-inflammation index (SII). The Ingenuity Pathway Analysis (IPA) was used to investigate the immune-cell related effects of ßcatenin and PD-L1 encoding genes. RESULTS: ßcatenin was expressed in 86.2% of GCTs. The expression in seminomas was significantly lower compared to all subtypes of non-seminoma (all P <  0.0001). A high expression (weighted histoscore > 150) was associated with primary mediastinal non-seminoma (P = 0.035), intermediate/poor risk disease (P = 0.033) and high tumor markers (P = 0.035). We observed a positive correlation with the PD-L1 in tumor and an inverse correlation with the SII. IPA uncovered relationships of CTNNB (ßcatenin) and CD274 (PD-L1) genes and their effects on differentiation, proliferation and activation of lymphocyte subtypes. CONCLUSION: Herein, we showed that ßcatenin is associated with male adult GCT characteristics as well as supressed immune environment.

Systemic immune-inflammation index in germ-cell tumours.

BACKGROUND: We evaluated systemic immune-inflammation index (SII) and its association with patient outcome in germ-cell tumours (GCTs). METHODS: Two independent cohorts of patients were analysed; the discovery set (n=171) from a single institution and the validation set (n=181) previously included in a study evaluating PD-L1 in GCTs. The SII was calculated using platelet (P), neutrophil (N) and lymphocyte (L) counts before chemotherapy and correlated with survival using regression analyses and Kaplan-Meier method. RESULTS: In the discovery cohort, the SII was associated with poor risk clinical features. Patients with low SII had significantly longer progression-free survival (HR=0.22, 95% CI 0.12-0.41, P<0.001) and overall survival (OS) (HR=0.16, 95% CI 0.08-0.32, P<0.001) compared to high SII. This index was independent of International Germ Cell Cancer Collaborative Group criteria in multivariable Cox regression analysis for OS and was validated in an independent cohort. When combining PD-L1 expression on tumour infiltrating lymphocytes (TILs) and SII, we identified three distinctive prognostic groups. CONCLUSIONS: High SII was associated with poor outcome in GCTs. Combination of PD-L1 positive TILs and SII could further refine prognosis in GCTs.

Prognostic value of intratumoral carbonic anhydrase IX expression in testicular germ cell tumors.

Testicular germ cell tumors (TGCTs) represent a highly curable malignancy, however a small proportion of patients fails to be cured with cisplatin-based chemotherapy. Carbonic anhydrase IX (CA IX) is upregulated by hypoxia in several cancer types and correlates with a poor prognosis. The present translational study evaluated expression and prognostic value of CA IX in TGCTs. Surgical specimens from 228 patients with TGCTs were processed by the tissue microarray method and subjected to immunohistochemistry with the M75 monoclonal antibody. CA IX expression was evaluated in tumors vs. adjacent normal testicular tissues and correlated with clinicopathological characteristics and clinical outcome. CA IX expression was detected in 62 (30.2%) of TGCTs compared to 0 (0%) of normal tissue adjacent to testicular tumor (P<0.001). The highest frequency of the CA IX expression was detected in teratoma (39.0%), followed by seminoma (22.7%), yolk sac tumor (22.2%), embryonal carcinoma (11.9%) and choriocarcinoma (7.7%). None of germ cell neoplasias in situ (GCNIS) exhibited CA IX expression. Patients without the CA IX tumor expression showed significantly better progression-free survival, but not overall survival, compared to patients with the CA IX expression [hazard ratio (HR), 0.57; 95% CI, 0.32-1.02; P=0.037 and HR, 0.58; 95% CI, 0.29-1.16; P=0.088, respectively]. There was no significant correlation between the CA IX expression and clinicopathological variables. The intratumoral CA IX expression can serve as a prognostic marker in the TGCT patients. These results suggest that activation of the hypoxia-induced pathways may be important in the treatment failure in TGCTs patients.

Prognostic role of programmed-death ligand 1 (PD-L1) expressing tumor infiltrating lymphocytes in testicular germ cell tumors.

PURPOSE: Testicular germ cell tumors (TGCTs) are nearly universally curable malignancies. Nevertheless, standard cisplatin-based chemotherapy is not curative in a small subgroup of patients. Previously, we showed that PD-L1 overexpression is associated with worse prognosis in TGCTs, while tumor infiltrating lymphocytes (TILs) are prognostic in different types of cancer. This study aimed to evaluate the prognostic value of PD-1 and PD-L1 expressing TILs in TGCTs. RESULTS: PD-L1 positive TILs were found significantly more often in seminomas (95.9% of patients) and embryonal carcinomas (91.0%) compared to yolk sac tumors (60.0%), choriocarcinomas (54.5%) or teratomas (35.7%) (All p < 0.05). TGCTs patients with high infiltration of PD-L1 positive TILs (HS ≥ 160) had significantly better progression-free survival (HR = 0.17, 95% CI 0.09 - 0.31, p = 0.0006) and overall survival (HR = 0.08, 95% CI 0.04 - 0.16, p = 0.001) opposite to patients with lower expression of PD-L1 (HS < 150). PD-1 expressing TILs were not prognostic in TGCTs. MATERIALS AND METHODS: Surgical specimens from 240 patients with primary TGCTs were included into this translational study. The PD-1 and PD-L1 expression on tumor and TILs were detected by immunohistochemistry using anti-PD-1 and anti-PD-L1 monoclonal antibody. Scoring was performed semiquantitatively by weighted histoscore (HS) method. CONCLUSIONS: The prognostic value of PD-L1 expressing TILs in TGCTs was demonstrated for the first time.

Plasma Cytokines Correlated With Disease Characteristics, Progression-Free Survival, and Overall Survival in Testicular Germ-Cell Tumor Patients.

BACKGROUND: Cytokines are the communicators of immune system and are involved in all immune responses. The aim of this study was to assess the correlation among plasma cytokines, patient and tumor characteristics, and clinical outcome in chemonaive testicular germ-cell tumor (TGCT) patients. PATIENTS AND METHODS: This study included 92 metastatic chemotherapy-naive TGCT patients treated with platinum-based chemotherapy from July 2010 to March 2014. Plasma was isolated before first administration of chemotherapy, and the concentration of 51 plasma cytokines were analyzed using multiplex bead arrays. RESULTS: At a median follow-up of 33.2 months (range, 0.1-54.8 months), 10.9% of patients experienced disease progression, and 7.6% died. Several cytokines were associated with different baseline clinicopathologic features. Elevated plasma levels of interferon (IFN)-α2, interleukin (IL)-2Rα, IL-16, hepatocyte growth factor (HGF), and monocyte chemotactic protein (MCP)-3 were significantly associated with worse progression-free survival and overall survival (OS). Moreover, elevated levels of stem-cell growth factor (SCGF)-ß were also associated with worse OS. Patients with elevated levels of all 6 cytokines experienced significantly worse outcomes compared to patients who had fewer than 6 cytokines elevated (hazard ratio = 12.06; 95% confidence interval, 7.39-19.49; P = .002 for progression-free survival, and hazard ratio = 39.65; 95% confidence interval, 25.03-62.18; P < .00001 for OS, respectively). Results were independent of International Germ Cell Cancer Collaborative Group criteria. CONCLUSION: We found a correlation among progression free-survival, OS, and circulating cytokines in TGCT. This suggests the existence an association between plasma cytokines and baseline clinicopathologic features in TGCT. Plasma cytokines could be used for identification of high-risk patients who are candidates for new therapeutic approaches.

PARP expression in germ cell tumours.

BACKGROUND: Poly(ADP-ribose)polymerase (PARP) inhibitors represent a new class of promising drugs in anticancer therapy. AIMS: To evaluate PARP expression in testicular germ cell tumours (GCTs) and to correlate expression patterns with clinicopathological variables. METHODS: In this translational study, tumour specimens from 124 patients with GCTs (114 patients with testicular primary tumours and 10 with extragonadal GCTs) were identified. PARP expression was detected by immunohistochemistry using monoclonal antibodies, scored by the multiplicative quickscore (QS) method and compared to PARP expression in normal testicular tissue. RESULTS: We observed higher expression of PARP in testicular tumours compared to normal testicular tissue (mean QS=10.04 vs 3.31, p<0.0000001). Mean QS±SD for each histological subtype was as follows: intratubular germ cell neoplasia unclassified (IGCNU)=18.00±0.00, embryonal carcinoma=9.62±5.64, seminoma=9.74±6.51, yolk sac tumour=7.8±7.20, teratoma=5.87±5.34, and choriocarcinoma=4.50±8.33. The PARP overexpression (QS>9) was most often detected in IGCNU (100% of specimen with PARP overexpression), seminona (52.6%), embryonal carcinoma (47.0%), yolk sac tumour (33.3%), teratoma (26.7%) and choriocarcinoma (25.0%), compared to 1.9% of normal testicular tissue specimens. There was no association between PARP expression and clinical variables. CONCLUSIONS: In this pilot study, we showed for the first time, that PARP is overexpressed in testicular germ cell tumours compared to normal testis.