Soluble lymphocyte activation gene-3 (sLAG3) and CD4/CD8 ratio dynamics as predictive biomarkers in patients undergoing immune checkpoint blockade for solid malignancies.

BACKGROUND: The search for biomarkers to identify suitable candidates for immune checkpoint inhibitor (ICI) therapy remains ongoing. We evaluate how soluble levels of the next generation immune checkpoint Lymphocyte Activation Gene-3 (sLAG-3) and its association with circulating T lymphocyte subsets could pose as a novel biomarker to predict outcome to ICI therapy. METHODS: Circulating levels of sLAG3 were analyzed using multiplex immunoassay in n = 84 patients undergoing ICI therapy for advanced solid cancer, accompanied by flow cytometry analyses of peripheral blood mononuclear cells (PBMCs). RESULTS: Uni- and multivariate analysis shows that patients with higher sLAG3 concentrations before ICI therapy had a significantly impaired progression-free (PFS) and overall survival (OS) (HRPFS: 1.005 [95%CI: 1.000-1.009], p = 0.039; HROS: 1.006 [95%CI: 1.001-1.011], p = 0.015). The CD4/CD8 cell ratio and its dynamics during therapy were strong predictors of PFS and OS with patients with a decreasing ratio between baseline and after 1-2 cycles having an improved median OS compared to patients with increasing values (p = 0.012, HR: 3.32). An immunological score combining sLAG3 and the CD4/CD8 ratio showed the highest predictive potential (HROS: 10.3). CONCLUSION: Pending prospective validation, sLAG3 and correlating circulating T-cell subsets can be used as a non-invasive predictive marker to predict outcome to ICI therapy to help identifying ideal ICI candidates in the future.

Peripheral blood CD3+HLADR+ cells and associated gut microbiome species predict response and overall survival to immune checkpoint blockade.

Background: The search for biomarkers to identify ideal candidates for immune checkpoint inhibitor (ICI) therapy is fundamental. In this study, we analyze peripheral blood CD3+HLADR+ cells (activated T-cells) as a novel biomarker for ICI therapy and how its association to certain gut microbiome species can indicate individual treatment outcomes. Methods: Flow cytometry analysis of peripheral mononuclear blood cells (PBMCs) was performed on n=70 patients undergoing ICI therapy for solid malignancies to quantify HLA-DR on circulating CD3+ cells. 16s-rRNA sequencing of stool samples was performed on n=37 patients to assess relative abundance of gut microbiota. Results: Patients with a higher frequency of CD3+HLADR+ cells before treatment initiation showed a significantly reduced tumor response and overall survival (OS), a worst response and experienced less toxicities to ICI therapy. As such, patients with a frequency of CD3+HLADR+ cells above an ideal cut-off value of 18.55% had a median OS of only 132 days compared to 569 days for patients below. Patients with increasing CD3+HLADR+ cell counts during therapy had a significantly improved OS. An immune signature score comprising CD3+HLADR+ cells and the neutrophil-lymphocyte ratio (NLR) was highly significant for predicting OS before and during therapy. When allied to the relative abundance of microbiota from the Burkholderiales order and the species Bacteroides vulgatus, two immune-microbial scores revealed a promising predictive and prognostic power. Conclusion: We identify the frequencies and dynamics of CD3+HLADR+ cells as an easily accessible prognostic marker to predict outcome to ICIs, and how these could be associated with immune modulating microbiome species. Two unprecedented immune-microbial scores comprising CD3+HLADR+, NLR and relative abundance of gut bacteria from the Burkhorderiales order or Bacteroides vulgatus species could accurately predict OS to immune checkpoint blockade.

Telomere Shortening in Peripheral Leukocytes Is Associated With Poor Survival in Cancer Patients Treated With Immune Checkpoint Inhibitor Therapy.

BACKGROUND: Immune checkpoint inhibitor (ICI) therapy represents a new standard of care for an increasing number of malignancies. Nevertheless, response rates and outcome of ICI treatment vary between individuals and the identification of predictive markers or hints towards immune cell exhaustion during therapy has remained a major challenge. Leukocyte telomere length is an established predictive biomarker of replicative aging and cellular proliferative potential in various hematological diseases. However, its relevance in the context of ICI therapy has not been investigated to date. Here, we analyze the age-adapted delta telomere length (ΔTL) of peripheral leukocytes as a potential predictive and prognostic marker in patients undergoing ICI therapy. METHODS: Age-adapted delta telomere length (ΔTL) of 84 patients treated with ICIs for solid malignancies was measured via quantitative real-time PCR. ΔTL was correlated with outcome and clinical data. RESULTS: ΔTL was not significantly altered between patients with different tumor entities or tumor stages and did not predict tumor response to ICI therapy. However, ΔTLs at initiation of treatment were a prognostic marker for overall survival (OS). When using a calculated ideal cut-off value, the median OS in patients with shorter ΔTL was 5.7 months compared to 18.0 months in patients showing longer ΔTL. The prognostic role of age-adapted ΔTL was further confirmed by uni- and multivariate Cox-regression analyses. CONCLUSION: In the present study, we demonstrate that shorter telomere lengths in peripheral blood leukocytes are associated with a significantly impaired outcome in patients receiving ICI therapy across different malignancies. We explain our findings by hypothesizing an older replicative age in peripheral leukocytes of patients with an impaired overall survival, reflected by a premature TL shortening. Whether this association is ICI-specific remains unknown. Further follow-up studies are needed to provide insights about the exact mechanism of how shortened telomeres eventually affect OS and could help guiding therapeutic decisions in future.

Progressive Sarcopenia Correlates with Poor Response and Outcome to Immune Checkpoint Inhibitor Therapy.

BACKGROUND: Immune checkpoint inhibitors (ICIs) represent a new therapeutic standard for an increasing number of tumor entities. Nevertheless, individual response and outcome to ICI is very heterogeneous, and the identification of the ideal ICI candidate has remained one of the major issues. Sarcopenia and the progressive loss of muscle mass and strength, as well as muscular fat deposition, have been established as negative prognostic factors for a variety of diseases, but their role in the context of ICI therapy is not fully understood. Here, we have evaluated skeletal muscle composition as a novel prognostic marker in patients undergoing ICI therapy for solid malignancies. METHODS: We analyzed patients with metastasized cancers receiving ICI therapy according to the recommendation of the specific tumor board. Routine CT scans before treatment initialization and during ICI therapy were used to assess the skeletal muscle index (L3SMI) as well as the mean skeletal muscle attenuation (MMA) in n = 88 patients receiving ICI therapy. RESULTS: While baseline L3SMI and MMA values were unsuitable for predicting the individual response and outcome to ICI therapy, longitudinal changes of the L3SMI and MMA (∆L3SMI, ∆MMA) during ICI therapy turned out to be a relevant marker of therapy response and overall survival. Patients who responded to ICI therapy at three months had a significantly higher ∆L3SMI compared to non-responders (-3.20 mm2/cm vs. 1.73 mm2/cm, p = 0.002). Moreover, overall survival (OS) was significantly lower in patients who had a strongly decreasing ∆L3SMI (<-6.18 mm2/cm) or a strongly decreasing ∆MMA (<-0.4 mm2/cm) during the first three month of ICI therapy. Median OS was only 127 days in patients with a ∆L3SMI of below -6.18 mm2/cm, compared to 547 days in patients with only mildly decreasing or even increasing ∆L3SMI values (p < 0.001). CONCLUSION: Both progressive sarcopenia and an increasing skeletal muscle fat deposition are associated with poor response and outcome to ICI therapy, which might help to guide treatment decisions during ICI therapy.

Serum Levels of Soluble Urokinase Plasminogen Activator Receptor Predict Tumor Response and Outcome to Immune Checkpoint Inhibitor Therapy.

BACKGROUND: Immune checkpoint inhibitors (ICIs) have led to a paradigm shift in cancer therapy, improving outcomes in the treatment of various malignancies. However, not all patients benefit to the same extend from ICI. Reliable tools to predict treatment response and outcome are missing. Soluble urokinase plasminogen activator receptor (suPAR) is a marker of immune activation, whose levels are prognostic in various cancers. We evaluated circulating suPAR levels as a novel predictive and prognostic biomarker in patients receiving ICI therapy for solid tumors. METHODS: A total of n = 87 patients receiving ICI therapy for different solid malignancies as well as 32 healthy controls were included into this study. Serum levels of suPAR were measured by ELISA prior to and sequentially at two time points during ICI therapy. RESULTS: Baseline suPAR serum levels were significantly higher in solid tumor patients compared to healthy controls. Importantly, patients with low suPAR levels both before or during ICI treatment were more likely to have a favorable response to treatment at three and six months, respectively. This finding was confirmed by multivariate binary logistic regression analysis including several clinicopathological parameters. Moreover, circulating suPAR levels before and during therapy were an independent prognostic factor for overall survival (OS). As such, patients with initial suPAR levels above our ideal prognostic cut-off value (4.86 ng/ml) had a median OS of only 160 days compared to 705 days for patients with suPAR levels below this cut-off value. Finally, low baseline suPAR levels identified a subgroup of patients who experienced ICI-related side effects which in turn were associated with favorable treatment response and outcome. CONCLUSION: Our data suggest that measurements of suPAR serum levels are a previously unknown, easily accessible tool to predict individual treatment response and outcome to ICI therapy. Circulating suPAR might therefore be implemented into stratification algorithms to identify the ideal candidates for ICI treatment.

Serum levels of soluble B and T lymphocyte attenuator predict overall survival in patients undergoing immune checkpoint inhibitor therapy for solid malignancies.

Therapy with immune checkpoint inhibitors (ICIs) can lead to durable tumor control in patients with various advanced stage malignancies. However, this is not the case for all patients, leading to an ongoing search for biomarkers predicting response and outcome to ICI. The B and T lymphocyte attenuator (BTLA) is an immune checkpoint expressed on immune cells that was shown to modulate therapeutic responses. Here, we evaluate circulating levels of its soluble form, soluble B and T lymphocyte attenuator (sBTLA), as a biomarker for the prediction of treatment response and outcome to ICI therapy. Serum levels of sBTLA were analyzed by multiplex immunoassay in n = 84 patients receiving ICI therapy for solid malignancies and 32 healthy controls. BTLA expression was evaluated on peripheral blood mononuclear cells in a subset of patients (n = 6) using multicolor flow cytometry. Baseline sBTLA serum levels were significantly higher in cancer patients compared to healthy controls. Importantly, circulating sBTLA levels were an independent prognostic factor for overall survival (OS). As such, patients with initial sBTLA levels above the calculated prognostic cutoff value (311.64 pg/mL) had a median OS of only 138 days compared to 526 for patients with sBTLA levels below this value (P = .001). Uni- and multivariate Cox regression analyses confirmed the prognostic role of sBTLA in the context of ICI therapy. Finally, we observed a significant correlation between sBTLA levels and the frequency of CD3 + CD8 + BTLA+ T cells in peripheral blood. Thus, our data suggest that circulating sBTLA could represent a noninvasive biomarker to predict outcome to ICI therapy, helping to select eligible therapy candidates.

Macrophage migration inhibitory factor predicts an unfavorable outcome after transarterial chemoembolization for hepatic malignancies.

Transarterial chemoembolization (TACE) is a therapeutic option for patients with intermediate-stage hepatocellular carcinoma (HCC) or metastatic liver cancers. Identifying those patients who particularly benefit from TACE remains challenging. Macrophage migration inhibitory factor (MIF) represents is an inflammatory protein described in patients with liver cancer, but no data on its prognostic relevance in patients undergoing TACE exist. Here, we evaluate MIF serum concentrations as a potential biomarker in patients undergoing TACE for primary and secondary hepatic malignancies. MIF serum concentrations were measured by multiplex immunoassay in 50 patients (HCC: n = 39, liver metastases: n = 11) before and 1 day after TACE as well as in 51 healthy controls. Serum concentrations of MIF did not differ between patients and healthy controls. Interestingly, in the subgroup of patients with larger tumor size, significantly more patients had increased MIF concentrations. Patients with an objective tumor response to TACE therapy showed comparable concentrations of serum MIF compared to patients who did not respond. MIF concentrations at day 1 after TACE were significantly higher compared to baseline concentrations. Importantly, baseline MIF concentrations above the optimal cutoff value (0.625 ng/ml) turned out as a significant and independent prognostic marker for a reduced overall survival (OS) following TACE: patients with elevated MIF concentrations showed a significantly reduced median OS of only 719 days compared to patients below the cutoff value (median OS: 1430 days, p = 0.021). Baseline MIF serum concentrations are associated with tumor size of intrahepatic malignancies and predict outcome of patients with liver cancer receiving TACE.

Elevated soluble urokinase plasminogen activator receptor serum levels indicate poor survival following transarterial chemoembolization therapy for hepatic malignancies: An exploratory analysis.

BACKGROUND AND AIM: Transarterial chemoembolization (TACE) represents a standard of care for patients with intermediate-stage hepatocellular carcinoma (HCC) or liver metastases. However, identification of the ideal candidates for TACE therapy remains challenging. The soluble urokinase plasminogen activator receptor (suPAR) has recently evolved as a prognostic marker in patients with cancer; however no data on suPAR in the context of TACE exists. METHODS: Serum levels of suPAR were measured by an enzyme-linked immunosorbent assay in n = 48 TACE patients (HCC: n = 38, liver metastases: n = 10) before intervention and 1 day after TACE, as well as in 20 healthy controls. RESULTS: Serum levels of suPAR were significantly elevated in patients with liver cancer compared to healthy controls. Patients with or without an objective tumor response to TACE therapy had comparable levels of circulating suPAR. Importantly, baseline suPARs above the ideal prognostic cut-off value (5.39 ng/mL) were a significant prognostic marker for reduced overall survival (OS) following TACE. As such, patients with initial suPAR levels >5.39 ng/mL showed a significantly reduced median OS of only 256 days compared to patients with suPAR serum levels below the cut-off value (median OS: 611 days). In line with previous data, suPAR serum concentrations correlated with those of creatinine but were independent of tumor entity, leukocyte count, and C-reactive protein in multivariate analysis. CONCLUSION: Baseline suPAR serum levels provide important information on the postinterventional outcome of liver cancer patients receiving TACE.

Circulating levels of soluble urokinase plasminogen activator receptor predict outcome after resection of biliary tract cancer.

BACKGROUND & AIMS: Surgical resection is the only potentially curative therapy for patients with biliary tract cancer (BTC), but 5-year survival rates after tumor resection have remained below 30%, corroborating the need for better stratification tools to identify the ideal surgical candidates. The soluble urokinase plasminogen activator receptor (suPAR) represents a mediator of inflammation and has been associated with distinct types of cancer. In this study, we evaluated a potential role of suPAR as a novel biomarker in patients undergoing BTC resection. METHODS: Tumor expression of uPAR was analyzed by immunohistochemistry in 108 BTC samples. Serum levels of suPAR were analyzed by ELISA in a training and validation cohort comprising a total of 117 patients with BTC and 76 healthy controls. RESULTS: High tumoral uPAR expression was associated with an adverse outcome after BTC resection. Accordingly, circulating levels of suPAR were significantly elevated in patients with BTC compared to healthy controls, as well as in patients with primary sclerosing cholangitis. Using a small training set, we established an optimal prognostic suPAR cut-off value of 3.72 ng/ml for patients with BTC. Importantly, preoperative suPAR serum levels above this cut-off value were associated with significantly impaired overall survival in both the training and validation cohort. Multivariate Cox-regression analysis including various clinicopathological parameters such as tumor stage, markers of inflammation and organ dysfunction, as well as tumor markers, revealed circulating suPAR levels as an independent prognostic marker following BTC resection. Finally, high preoperative suPAR levels were indicative of acute kidney injury after tumor resection. CONCLUSION: Circulating suPAR represents a previously unrecognized biomarker in patients with resectable BTC, which might help to preoperatively identify the ideal candidates for liver surgery. LAY SUMMARY: Surgical resection represents the only curative treatment option for patients with biliary tract cancer, but not all patients benefit to the same extent in terms of overall survival. Here, we provide evidence that serum levels of an inflammatory mediator (suPAR) are indicative of a patient's postoperative outcome and might thus help to identify the ideal surgical candidates.