Low-molecular-weight heparin prophylaxis is not associated with decreased incidence of venous thromboembolism in testicular germ cell tumor patients receiving chemotherapy.

Venous thromboembolism (VTE), commonly occurring in patients with testicular germ cell tumors (GCTs), is associated with increased morbidity and mortality. Prophylactic anticoagulation has been shown to decrease the risk of VTE in patients with malignancies. The objective was to evaluate the effect of low-molecular-weight heparin (LMWH) prophylaxis on the incidence of VTE and outcome in patients with GCT treated with first-line chemotherapy. In this retrospective study, 353 chemotherapy-naive GCT patients were treated with first-line chemotherapy at the National Cancer Institute, Bratislava, Slovakia (2000-2017). Median follow-up was 71 months. VTE was defined as any venous thrombosis or pulmonary embolism, confirmed by imaging, occurring during first-line chemotherapy. Exclusion criteria were LMWH use before starting chemotherapy and VTE on initial staging. We observed 14 (4.0%) VTE events. No visceral thromboses were observed. The difference in VTE incidence between patients with and without prophylaxis was not statistically significant (5.8% vs. 3.2%, p=0.37). We observed a trend toward longer overall survival in patients without prophylaxis (hazard ratio = 0.61, 95% confidence interval = 0.32-1.13, p=0.08). Patients with extragonadal GCT receiving VTE prophylaxis had significantly shorter survival (hazard ratio = 0.29, 95% confidence interval = 0.08-1.12, p=0.04). This effect was most likely driven by a higher incidence of treatment-related deaths in patients with extragonadal GCT receiving LMWH (p=0.06). LMWH prophylaxis was not associated with decreased VTE incidence. Moreover, there was a higher incidence of treatment-related deaths in patients with extragonadal tumor location. Low-molecular-weight heparin prophylaxis during hospitalization should not be used routinely in patients with testicular germ cell tumors receiving chemotherapy.

Uncovering Microbial Composition in Human Breast Cancer Primary Tumour Tissue Using Transcriptomic RNA-seq.

Recent research studies are showing breast tissues as a place where various species of microorganisms can thrive and cannot be considered sterile, as previously thought. We analysed the microbial composition of primary tumour tissue and normal breast tissue and found differences between them and between multiple breast cancer phenotypes. We sequenced the transcriptome of breast tumours and normal tissues (from cancer-free women) of 23 individuals from Slovakia and used bioinformatics tools to uncover differences in the microbial composition of tissues. To analyse our RNA-seq data (rRNA depleted), we used and tested Kraken2 and Metaphlan3 tools. Kraken2 has shown higher reliability for our data. Additionally, we analysed 91 samples obtained from SRA database, originated in China and submitted by Sichuan University. In breast tissue, the most enriched group were Proteobacteria, then Firmicutes and Actinobacteria for both datasets, in Slovak samples also Bacteroides, while in Chinese samples Cyanobacteria were more frequent. We have observed changes in the microbiome between cancerous and healthy tissues and also different phenotypes of diseases, based on the presence of circulating tumour cells and few other markers.

Targeting of Deregulated Wnt/ß-Catenin Signaling by PRI-724 and LGK974 Inhibitors in Germ Cell Tumor Cell Lines.

The majority of patients with testicular germ cell tumors (GCTs) can be cured with cisplatin-based chemotherapy. However, for a subset of patients present with cisplatin-refractory disease, which confers a poor prognosis, the treatment options are limited. Novel therapies are therefore urgently needed to improve outcomes in this challenging patient population. It has previously been shown that Wnt/ß-catenin signaling is active in GCTs suggesting that its inhibitors LGK974 and PRI-724 may show promise in the management of cisplatin-refractory GCTs. We herein investigated whether LGK-974 and PRI-724 provide a treatment effect in cisplatin-resistant GCT cell lines. Taking a genoproteomic approach and utilizing xenograft models we found the increased level of ß-catenin in 2 of 4 cisplatin-resistant (CisR) cell lines (TCam-2 CisR and NCCIT CisR) and the decreased level of ß-catenin and cyclin D1 in cisplatin-resistant NTERA-2 CisR cell line. While the effect of treatment with LGK974 was limited or none, the NTERA-2 CisR exhibited the increased sensitivity to PRI-724 in comparison with parental cell line. Furthermore, the pro-apoptotic effect of PRI-724 was documented in all cell lines. Our data strongly suggests that a Wnt/ß-catenin signaling is altered in cisplatin-resistant GCT cell lines and the inhibition with PRI-724 is effective in NTERA-2 CisR cells. Further evaluation of Wnt/ß-catenin pathway inhibition in GCTs is therefore warranted.

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.

Napabucasin overcomes cisplatin resistance in ovarian germ cell tumor-derived cell line by inhibiting cancer stemness.

BACKGROUND: Cisplatin resistance of ovarian yolk sac tumors (oYST) is a clinical challenge due to dismal patient prognosis, even though the disease is extremely rare. We investigated potential association between cisplatin resistance and cancer stem cell (CSC) markers in chemoresistant oYST cells and targeting strategies to overcome resistance in oYST. METHODS: Chemoresistant cells were derived from chemosensitive human oYST cells by cultivation in cisplatin in vitro. Derivative cells were characterized by chemoresistance, functional assays, flow cytometry, gene expression and protein arrays focused on CSC markers. RNAseq, methylation and microRNA profiling were performed. Quail chorioallantoic membranes (CAM) with implanted oYST cells were used to analyze the micro-tumor extent and interconnection with the CAM. Tumorigenicity in vivo was determined on immunodeficient mouse model. Chemoresistant cells were treated by inhibitors intefering with the CSC properties to examine the chemosensitization to cisplatin. RESULTS: Long-term cisplatin exposure resulted in seven-fold higher IC50 value in resistant cells, cross-resistance to oxaliplatin and carboplatin, and increased migratory capacity, invasiveness and tumorigenicity, associated with hypomethylation of differentially methylated genes/promotors. Resistant cells exhibited increased expression of prominin-1 (CD133), ATP binding cassette subfamily G member 2 (ABCG2), aldehyde dehydrogenase 3 isoform A1 (ALDH3A1), correlating with reduced gene and promoter methylation, as well as increased expression of ALDH1A3 and higher overall ALDH enzymatic activity, rendering them cross-resistant to DEAB, disulfiram and napabucasin. Salinomycin and tunicamycin were significantly more toxic to resistant cells. Pretreatment with napabucasin resensitized the cells to cisplatin and reduced their tumorigenicity in vivo. CONCLUSIONS: The novel chemoresistant cells represent unique model of refractory oYST. CSC markers are associated with cisplatin resistance being possible targets in chemorefractory oYST.

Increased levels of XPA might be the basis of cisplatin resistance in germ cell tumours.

BACKGROUND: Germ cell tumours (GCTs) represent a highly curable malignity as they respond well to cisplatin (CDDP)-based chemotherapy. Nevertheless, a small proportion of GCT patients relapse or do not respond to therapy. As this might be caused by an increased capacity to repair CDDP-induced DNA damage, identification of DNA repair biomarkers predicting inadequate or aberrant response to CDDP, and thus poor prognosis for GCT patients, poses a challenge. The objective of this study is to examine the expression levels of the key nucleotide excision repair (NER) factors, XPA, ERCC1 and XPF, in GCT patients and cell lines. METHODS: Two hundred seven GCT patients' specimens with sufficient follow-up clinical-pathological data and pairwise combinations of CDDP-resistant and -sensitive GCT cell lines were included. Immunohistochemistry was used to detect the ERCC1, XPF and XPA protein expression levels in GCT patients' specimen and Western blot and qRT-PCR examined the protein and mRNA expression levels in GCT cell lines. RESULTS: GCT patients with low XPA expression had significantly better overall survival than patients with high expression (hazard ratio = 0.38, 95% confidence interval: 0.12-1.23, p = 0.0228). In addition, XPA expression was increased in the non-seminomatous histological subtype, IGCCCG poor prognosis group, increasing S stage, as well as the presence of lung, liver and non-pulmonary visceral metastases. Importantly, a correlation between inadequate or aberrant CDDP response and XPA expression found in GCT patients was also seen in GCT cell lines. CONCLUSIONS: XPA expression is an additional independent prognostic biomarker for stratifying GCT patients, allowing for improvements in decision-making on treatment for those at high risk of refractoriness or relapse. In addition, it could represent a novel therapeutic target in GCTs.

Cancer Stem Cell Niche and Immune-Active Tumor Microenvironment in Testicular Germ Cell Tumors.

Testicular germ cell tumors (TGCTs) represent the most common neoplasia among young men. Management of TGCTs is an excellent example of curative outcomes in clinical oncology. The unique sensitivity to cisplatin-based chemotherapy regimens has led to establishing TGCTs as a "model of cancer cure." However, mechanisms and factors underlying pervasive growth of TGCTs are still poorly understood. It is suggested that unique cancer stem cell (CSC) niche exists in the testicular tumor microenvironment. CSC niche potentially contributes to the progression of germ cell tumors. Furthermore, rich infiltration of TGCTs with immune cells indicates involvement of immune system in biology of this cancer type. This review summarizes current knowledge regarding specific cancer microenvironment in TGCTs and discusses the role of cancer stem cells as well as immune mechanisms in these tumors.

Increased Stromal Infiltrating Lymphocytes Are Associated with the Risk of Disease Progression in Mesenchymal Circulating Tumor Cell-Positive Primary Breast Cancer Patients.

Circulating tumor cells (CTCs) and the immune infiltration of tumors are closely related to clinical outcomes. This study aimed to verify the influence of stromal lymphocyte infiltration and the immune context of tumor microenvironment on the hematogenous spread and prognosis of 282 chemotherapy naïve primary BC patients. To detect the presence of mesenchymal CTCs, RNA extracted from CD45-depleted peripheral blood was interrogated for the expression of mesenchymal gene transcripts. Tumor-infiltrating lymphocytes (TILs) were detected in the stromal areas by immunohistochemistry, using CD3, CD8, and CD45RO antibodies. The concentrations of 51 plasma cytokines were measured by multiplex bead arrays. TILs infiltration in mesenchymal CTC-positive patients significantly decreased their progression-free survival (HR = 4.88, 95% CI 2.30-10.37, p < 0.001 for CD3high; HR = 6.17, 95% CI 2.75-13.80, p < 0.001 for CD8high; HR = 6.93, 95% CI 2.86-16.81, p < 0.001 for CD45ROhigh). Moreover, the combination of elevated plasma concentrations of transforming growth factor beta-3 (cut-off 662 pg/mL), decreased monocyte chemotactic protein-3 (cut-off 52.5 pg/mL) and interleukin-15 (cut-off 17.1 pg/mL) significantly increased the risk of disease recurrence (HR = 4.838, 95% CI 2.048-11.427, p < 0.001). Our results suggest a strong impact of the immune tumor microenvironment on BC progression, especially through influencing the dissemination and survival of more aggressive, mesenchymal CTC subtypes.

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.

Long-Term Cognitive Functioning in Testicular Germ-Cell Tumor Survivors.

BACKGROUND: Treatment for cancer may lead to development of cognitive difficulties in cancer survivors. This study aimed to evaluate long-term cognitive functioning (CogF) in germ-cell tumor (GCT) survivors. SUBJECTS, MATERIALS, AND METHODS: GCT survivors (n = 155) from the National Cancer Institute of Slovakia completed the Functional Assessment of Cancer Therapy Cognitive Function at a median of 10 years of follow-up (range: 5-32). The study group consisted of survivors receiving a cisplatin-based chemotherapy, radiotherapy to the retroperitoneal lymph nodes, or both, whereas the control group included survivors treated with orchiectomy only. RESULTS: Of the total survivors, 138 received treatment beyond orchiectomy and 17 controls had orchiectomy alone. Any treatment resulted in significantly greater cognitive difficulties on the overall cognitive function score. Treatment with radiotherapy was associated with cognitive declines in overall cognitive functioning and in subscales for perceived cognitive impairment and cognitive impairment perceived by others (both p < .05). The burden of chemotherapy plus radiotherapy or radiotherapy versus controls resulted in the impairment in all cognitive functioning domains (all p < .05). Overall long-term cognitive impairment was independent of age in the multivariable analysis. CONCLUSION: This prospective study shows that GCT survivors suffer from a long-term CogF impairment. These results may help guide clinicians' decisions in treatment and follow-up of GCTs. IMPLICATIONS FOR PRACTICE: In this study, long-term survivors of germ-cell tumors have reported cognitive impairment after curative treatment with radiotherapy and chemotherapy compared with controls who had treatment with orchiectomy only. These data provide an argument against the use of adjuvant radiotherapy for stage I seminoma. Unnecessary overtreatment with chemotherapy and additional radiotherapy after chemotherapy should be avoided.

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.

Molecular Mechanisms of Cisplatin Chemoresistance and Its Circumventing in Testicular Germ Cell Tumors.

PURPOSE OF REVIEW: Testicular germ cell tumors (TGCTs) represent the most common solid tumors affecting young men. Majority of TGCTs respond well to cisplatin-based chemotherapy. However, patients with refractory disease have limited treatment modalities associated with poor prognosis. Here, we discuss the main molecular mechanisms associated with acquired cisplatin resistance in TGCTs and how their understanding might help in the development of new approaches to tackle this clinically relevant problem. We also discuss recent data on the strategies of circumventing the cisplatin resistance from different tumor types potentially efficient also in TGCTs. RECENT FINDINGS: Recent data regarding deregulation of various signaling pathways as well as genetic and epigenetic mechanisms in cisplatin-resistant TGCTs have contributed to understanding of the mechanisms related to the resistance to cisplatin-based chemotherapy in these tumors. Understanding of these mechanisms enabled explaining why majority but not all TGCTs patients are curable with cisplatin-based chemotherapy. Moreover, it could lead to the development of more effective treatment of refractory TGCTs and potentially other solid tumors resistant to platinum-based chemotherapy. This review provides additional insights into mechanisms associated with cisplatin resistance in TGCTs, which is a complex phenomenon, and there is a need for novel modalities to overcome it.

Chemotherapy-Induced Peripheral Neuropathy (CIPN) as a Predictor of Decreased Quality of Life in Testicular Germ Cell Tumor Survivors.

BACKGROUND: Chemotherapy-induced peripheral neuropathy (CIPN) after curative treatment for testicular germ cell tumors (GCTs) has been previously reported. It has been shown that CIPN can contribute to impaired quality of life (QOL) in cancer survivors. Herein, we aimed to evaluate CIPN in association with QOL in GCT survivors. PATIENTS AND METHODS: European Organization for Research and Treatment of Cancer (EORTC) Quality of Life - Chemotherapy-Induced Peripheral Neuropathy questionnaire (QLQ-CIPN20) and Quality of Life Questionnaire (QLQ-C30) were prospectively completed by GCT survivors (N = 151) at National Cancer Institute in Slovakia during their annual follow-up. The median follow-up was 10 years (range 4-30). Upon obtaining the scores from each questionnaire, each score from QLQ-C30 was correlated with CIPN defined as high or low (above and below median) as obtained from CIPN20. RESULTS: GCT survivors with high overall CIPN score reported impaired QOL in QLQ-C30. The global health status was lower in survivors with high CIPN versus low CIPN (mean score ± SEM: 67.17 ± 2.00 vs. 86.18 ± 1.76, P < .00001). Survivors with high CIPN reported worse physical, role, emotional, cognitive, and social functioning compared to survivors with low CIPN (all P < .00001). CIPN high survivors perceived more fatigue, nausea, pain, dyspnea, sleeping disorders, and appetite loss compared to CIPN low survivors (all P < .004). Higher burden of CIPN was associated with more financial problems vs CIPN low (mean score ± SEM: 19.70 ± 2.64 vs. 6.67 ± 2.32, P = .00025). Spearman analysis has confirmed negative correlation of overall CIPN20 score with QLQ-C30 global health status (R = -0.53, P < .0001). CONCLUSION: CIPN is a strong predictor of impairment in QOL among GCT survivors. Molecular mechanisms of neurotoxicity should be intensively studied to find preventive and therapeutic strategies.

DNA damage levels in peripheral blood mononuclear cells before and after first cycle of chemotherapy have comparable prognostic values in germ cell tumor patients.

Background: Germ cell tumors (GCTs) represent the most frequent solid malignancy in young men. This malignancy is highly curable by cisplatin (CDDP)-based chemotherapy. However, there is a proportion of patients having a poor prognosis due to refractory disease or its relapse. No reliable biomarkers being able to timely and accurately stratify poor prognosis GCT patients are currently available. Previously, we have shown that chemotherapy-naïve GCT patients with higher DNA damage levels in peripheral blood mononuclear cells (PBMCs) have significantly worse prognosis compared to patients with lower DNA damage levels. Methods: DNA damage levels in PBMCs of both chemotherapy-naïve and first cycle chemotherapy-treated GCT patients have been assessed by standard alkaline comet assay and its styrene oxide (SO)-modified version. These levels were correlated with clinico-pathological characteristics. Results: We re-confirm prognostic value of DNA damage level in chemotherapy-naïve GCT patients and reveal that this prognosticator is equally effective in GCT patients after first cycle of CDDP-based chemotherapy. Furthermore, we demonstrate that SO-modified comet assay is comparably sensitive as standard alkaline comet assay in case of patients who underwent first cycle of CDDP-based chemotherapy, although it appears more suitable to detect DNA cross-links. Conclusion: We propose that DNA damage levels in PBMCs before and after first cycle of CCDP-based chemotherapy are comparable independent prognosticators for progression-free and overall survivals in GCT patients. Therefore, their clinical use is highly advised to stratify GCT patients to identify those who are most at risk of developing disease recurrence or relapse, allowing tailoring therapeutic interventions to poor prognosis individuals, and optimizing their care management and treatment regimen.

Prognostic role of plasma vitamin D and its association with disease characteristics in germ cell tumours.

Background: Testicular cancer is the most common malignancy among young men. Vitamin D has pluripotent effects on cancer pathogenesis and plays a role in the metastatic cascade. The aim of this study is to analyze plasma vitamin D in association with clinico-pathological findings and prognosis in patients with germ-cell tumors (GCTs). Methods: This study included 120 newly diagnosed and/or relapsed GCT patients treated from April 2013 to July 2020, for whom plasma was available in the biobank. Blood samples were drawn the 1st chemotherapy cycle as well as before the 2nd cycle. Plasma vitamin D was measured using ELISA and correlated with disease characteristics and the outcome. For survival analysis, the cohort was dichotomized into "low" and "high" based on median vitamin D. Results: There was no significant difference in vitamin D plasma levels between healthy donors and GCT patients (p = 0.71). Vitamin D level was not associated with disease characteristics except for brain metastases, where patients with brain metastases had a vitamin D level that was 32% lower compared to patients without brain metastases, p = 0.03. Vitamin D was also associated with response to chemotherapy, with an approximately 32% lower value in patients with an unfavorable response compared to a favorable response, p = 0.02. Moreover, low plasma levels of vitamin D were significantly associated with disease recurrence and inferior progression-free survival (PFS), but not with overall survival (OS) (HR = 3.02, 95% CI 1.36-6.71, p = 0.01 for PFS and HR = 2.06, 95% CI 0.84-5.06, p = 0.14 for OS, respectively). Conclusion: Our study suggests the prognostic value of pretreatment vitamin D concentrations in GCT patients. Low plasma vitamin D was associated with an unfavorable response to therapy and disease recurrence. However, it remains to be determined whether the biology of the disease confirms a causative role for low vitamin D and whether its supplementation affects the outcome.

Cognitive impairment and biomarkers of gut microbial translocation in testicular germ cell tumor survivors.

Background: Survivors of testicular germ cell tumors (GCT) may suffer from late cognitive impairment. We hypothesized that disruption of intestinal barrier during chemotherapy and/or radiotherapy may be a contributing factor of cognitive dysfunction within the gut-blood-brain axis. Methods: GCT survivors (N = 142) from National Cancer Institute of Slovakia completed the Functional Assessment of Cancer Therapy Cognitive Function questionnaires during their annual follow-up visit at 9-year median (range 4-32). Biomarkers of gut microbial translocation and dysbiosis high mobility group box-1 (HMGB-1), lipopolysaccharide, d-lactate and sCD14 were measured from peripheral blood obtained during the same visit. Each questionnaire score was correlated with biomarkers. Survivors were treated with orchiectomy only (N = 17), cisplatin-based chemotherapy (N = 108), radiotherapy to the retroperitoneum (N = 11) or both (N = 6). Results: GCT survivors with higher sCD14 (above median) had worse cognitive function perceived by others (CogOth domain) (mean ± SEM; 14.6 ± 0.25 vs 15.4 ± 0.25, p = 0.019), lower perceived cognitive abilities (CogPCA domain) (20.0 ± 0.74 vs 23.4 ± 0.73, p = 0.025) and lower overall cognitive function score (109.2 ± 0.74 vs 116.7 ± 1.90, p = 0.021). There were no significant cognitive declines associated with HMGB-1, d-lactate and lipopolysaccharide. Survivors treated with ≥ 400mg/m2 vs < 400mg/m2 of cisplatin-based chemotherapy had a higher lipopolysaccharide (567.8 µg/L ± 42.7 vs 462.9 µg/L ± 51.9, (p = 0.03). Conclusions: sCD14 is a marker of monocytic activation by lipopolysaccharide and may also serve as a promising biomarker of cognitive impairment in long-term cancer survivors. While chemotherapy and radiotherapy-induced intestinal injury may be the underlying mechanism, further research using animal models and larger patient cohorts are needed to explore the pathogenesis of cognitive impairment in GCT survivors within the gut-brain axis.

Overcoming Chemotherapy Resistance in Germ Cell Tumors.

Testicular germ cell tumors (GCTs) are highly curable malignancies. Excellent survival rates in patients with metastatic disease can be attributed to the exceptional sensitivity of GCTs to cisplatin-based chemotherapy. This hypersensitivity is probably related to alterations in the DNA repair of cisplatin-induced DNA damage, and an excessive apoptotic response. However, chemotherapy fails due to the development of cisplatin resistance in a proportion of patients. The molecular basis of this resistance appears to be multifactorial. Tracking the mechanisms of cisplatin resistance in GCTs, multiple molecules have been identified as potential therapeutic targets. A variety of therapeutic agents have been evaluated in preclinical and clinical studies. These include different chemotherapeutics, targeted therapies, such as tyrosine kinase inhibitors, mTOR inhibitors, PARP inhibitors, CDK inhibitors, and anti-CD30 therapy, as well as immune-checkpoint inhibitors, epigenetic therapy, and others. These therapeutics have been used as single agents or in combination with cisplatin. Some of them have shown promising in vitro activity in overcoming cisplatin resistance, but have not been effective in clinical trials in refractory GCT patients. This review provides a summary of current knowledge about the molecular mechanisms of cisplatin sensitivity and resistance in GCTs and outlines possible therapeutic approaches that seek to overcome this chemoresistance.

Glycan signatures for the identification of cisplatin-resistant testicular cancer cell lines: Specific glycoprofiling of human chorionic gonadotropin (hCG).

BACKGROUND: Testicular cancer (TC) is the most frequent type of cancer among young men aged between 15 and 34 years. TC is treated using cisplatin, but 3%-5% of TC patients fail to respond to cisplatin, with a very bad to fatal prognosis. Accordingly, it is most important to quickly and readily identify those TC patients who are resistant to cisplatin treatment. METHODS: This study seeks to investigate changes in the glycosylation associated with cisplatin resistance to TC cell lines. RESULTS: A specific glycoprofiling of human chorionic gonadotropin (hCG) was analysed in three TC cell lines and one cell line of female origin. A typical calibration curve for hCG glycoprofiling showed a dynamic range up to 50 ng/ml, with a limit of detection of 0.3 ng/ml and assay reproducibility represented by relative standard deviation of 3.0%. Changes in the glycan signatures on hCG were analysed in cisplatin-sensitive cell lines and in their cisplatin-resistant sub-lines using an enzyme-linked lectin assay (ELLA) protocol. An immobilised antibody was applied to a selective capture of hCG from a cytoplasmic fraction of cell lysates with final incubation using a lectin from a panel of 17 lectins. CONCLUSION: The results suggest that one particular lectin Dolichos biflorus agglutinin (DBA) can selectively discriminate sensitive TC cell lines from resistant TC cell lines. Moreover, there are additional lectins which can provide useful information about the strength of cisplatin resistance.

Effect of the PARP inhibitor veliparib on germ cell tumor cell lines.

Germ cell tumors (GCTs) usually represent efficiently curable neoplasms due to their chemosensitivity to platinum-based therapeutic regimen. However, some patients develop therapeutic resistance and succumb to their disease. Novel therapeutic approaches are therefore needed for these patients. It has previously been demonstrated that poly (ADP-ribose) polymerase (PARP) expression is upregulated in GCTs compared with normal testis tissue. Therefore, PARP expression was analyzed in GCT cell lines and xenografts and it was examined whether its inhibition by veliparib can reverse cisplatin-resistance. Its expression was analyzed in sensitive and cisplatin-resistant variants (referred to as CisR throughout the manuscript) GCT cell lines and xenografts using quantitative PCR, western blotting and immunohistochemistry. The present study investigated whether the combination of cisplatin with the PARP inhibitor veliparib increased the cytotoxic effect of cisplatin in vitro using a luminescent viability assay and an immunodeficient mouse model in vivo. PARP expression was observed in all tested cell lines, with the highest expression in embryonal carcinoma (EC) cell lines and xenografts. Low or no expression was detected in the JEG-3 choriocarcinoma cell line pairs and xenografts. The combination of veliparib and cisplatin or carboplatin was examined in the cisplatin-resistant NTERA-2 CisR and NCCIT CisR EC cell lines and synergistic effects were observed in NTERA-2 CisR cells. However, in vivo analysis did not confirm this synergy. The present data indicated PARP expression in GCT cell lines and xenografts. However, veliparib failed to increase the cytotoxicity of platinum-based drugs. Therefore, further research is warranted to effectively inhibit PARP using different PARP inhibitors or other drug combinations.

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.