Implications of cancer-associated systemic inflammation for biomarker studies

Prognostic value of pretreatment neutrophil count in metastatic renal cell carcinoma: a systematic review and meta-analysis

Background: In recent years, inflammation has become widely recognized as a crucial component in tumor development and progression. Neutrophils are one of the most common inflammatory markers during hematological examinations. The prognostic value of neutrophils in metastatic renal cell carcinoma (mRCC) remains inconsistent. The aim of this meta-analysis is to evaluate the prognostic value of pretreatment neutrophil count in patients with mRCC.

Methods: PubMed, Web of Science and Embase were searched for data on the association between pretreatment neutrophil count and mRCC prognosis up to October 7, 2017. We sorted out relevant studies and extracted the hazard ratio (HR) and its 95% confidence interval (CI) for overall survival (OS) and progression-free survival (PFS).

Results: A total of 13 studies containing 3,021 patients with mRCC were summarized in the present meta-analysis. An elevated pretreatment neutrophil count yielded a worse OS (HR=2.17, 95% CI=1.68–2.79, P<0.001) and PFS (HR=1.78, 95% CI=0.91–3.49, P<0.001). Furthermore, we performed a subgroup analysis based on cut-off value, ethnicity, treatment method and analysis type. As a result, the association between pretreatment neutrophil count and survival was statistically significant in the subgroups of cut-off value, ethnicity, treatment method and analysis type.

Conclusion: Our results show that the pretreatment neutrophil count is associated with mRCC outcomes and can be used as a valuable inflammatory marker for prognosis monitoring.

Neutrophil-lymphocyte ratio is a predictor of prognosis in patients with castration-resistant prostate cancer: a meta-analysis

Background

The prognostic value of neutrophil–lymphocyte ratio (NLR) in patients with castration-resistant prostate cancer (CRPC) had been investigated in previous studies; however, the results remain inconsistent. This study was aimed to investigate the prognostic value of NLR in CRPC patients.

Materials and methods

Literature was identified from PubMed, Embase, Web of Science, and Cochrane, which investigated the relationship between pretreatment NLR and prognosis in CRPC patients. HRs for overall survival (OS) and progression-free survival (PFS) were extracted from eligible studies. Heterogeneity was assessed using the I2 value. The fixed-effects model was used if there was no evidence of heterogeneity; otherwise, the random-effects model was used. Publication bias was evaluated using Begg’s funnel plot test.

Results

A total of 5,705 patients from 16 studies were included in this analysis. The pooled results showed that an elevated NLR predict poor OS (pooled HR = 1.52, 95% CI: 1.41–1.63, P<0.001) and PFS (pooled HR = 1.50, 95% CI: 1.21–1.85, P<0.001) in patients with CRPC. Subgroup analysis revealed that an elevated NLR significantly predicted poor OS in Asian studies group (HR = 2.43, 95% CI: 1.47–4.01, P=0.001). The elevated NLR also significantly predicted poor PFS in Asian studies group (HR = 1.99, 95% CI: 1.30–3.06, P=0.002).

Conclusion

This study suggests that an elevated NLR predict poor prognosis in patients with CRPC.

Meta-analysis of the efficacy of the pretreatment neutrophil-to-lymphocyte ratio as a predictor of prognosis in renal carcinoma patients receiving tyrosine kinase inhibitors

The data on the impact of the neutrophil-to-lymphocyte ratio (NLR) in metastatic renal cell carcinoma (mRCC) patients receiving tyrosine kinase inhibitors (TKIs) are inconsistent. We therefore performed a meta-analysis to assess the prognostic value of pretreatment NLR in patients treated with TKIs for mRCC. We searched the Embase, Medline, PubMed, Cochrane and ISI Web of Knowledge to identify clinical studies that had evaluated the association between the pretreatment NLR and prognosis in mRCC patients. Prognostic outcomes included overall survival (OS) and progression-free survival (PFS). Nine studies encompassing a total of 1091 participants were included. We found that a high NLR was an effective prognostic marker of both OS (pooled HR: 1.93, 95% CI: 1.35-2.77; P = 0.0003) and PFS (pooled HR: 2.12, 95% CI: 1.42-3.17; P = 0.0002). Subgroup analysis revealed that studies reporting a NLR ≥ 3 showed a more significant effect of NLR on both OS (pooled HR: 2.50, 95% CI: 1.99-3.14; P = 0.0003) and PFS (pooled HR: 2.17, 95% CI: 1.26-3.75). This meta-analysis suggests that high pretreatment NLR is associated with a poor prognosis in mRCC patients receiving TKI treatment.

Cell-free chromatin from dying cancer cells integrate into genomes of bystander healthy cells to induce DNA damage and inflammation

Bystander cells of the tumor microenvironment show evidence of DNA damage and inflammation that can lead to their oncogenic transformation. Mediator(s) of cell-cell communication that brings about these pro-oncogenic pathologies has not been identified. We show here that cell-free chromatin (cfCh) released from dying cancer cells are the key mediators that trigger both DNA damage and inflammation in the surrounding healthy cells. When dying human cancer cells were cultured along with NIH3T3 mouse fibroblast cells, numerous cfCh emerged from them and rapidly entered into nuclei of bystander NIH3T3 cells to integrate into their genomes. This led to activation of H2AX and inflammatory cytokines NFκB, IL-6, TNFα and IFNγ. Genomic integration of cfCh triggered global deregulation of transcription and upregulation of pathways related to phagocytosis, DNA damage and inflammation. None of these activities were observed when living cancer cells were co-cultivated with NIH3T3 cells. However, upon intravenous injection into mice, both dead and live cells were found to be active. Living cancer cells are known to undergo extensive cell death when injected intravenously, and we observed that cfCh emerging from both types of cells integrated into genomes of cells of distant organs and induced DNA damage and inflammation. γH2AX and NFκB were frequently co-expressed in the same cells suggesting that DNA damage and inflammation are closely linked pathologies. As concurrent DNA damage and inflammation is a potent stimulus for oncogenic transformation, our results suggest that cfCh from dying cancer cells can transform cells of the microenvironment both locally and in distant organs providing a novel mechanism of tumor invasion and metastasis. The afore-described pro-oncogenic pathologies could be abrogated by concurrent treatment with chromatin neutralizing/degrading agents suggesting therapeutic possibilities.

Preoperative Neutrophil-Lymphocyte and Lymphocyte-Monocyte Ratios Reflect Immune Cell Population Rearrangement in Resectable Pancreatic Cancer

BACKGROUND

Neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), and lymphocyte-monocyte ratio (LMR) may serve as a simple index of the immune function. The aim of this study was to investigate the prognostic significance of NLR, PLR, and LMR in patients with resectable pancreatic ductal adenocarcinoma (PDAC) and to verify whether such biomarkers are associated with changes in populations of lymphoid cells.

METHODS

The prognostic implications of blood count parameters were evaluated in a retrospective cohort of 442 subjects undergoing pancreatic resections for PDAC. Subpopulations of lymphocytes and monocytes in peripheral blood were identified by FACS in a prospective cohort of 54 patients.

RESULTS

In the univariate analysis, NLR < 5 and LMR ≥ 3 were associated with significantly longer median survival of 25.7 vs 12.6 months and 29.2 vs 13.1 months, respectively. PLR did not influence survival. The Cox proportional hazards model showed that high NLR (HR 1.66, 95 % CI 1.12 to 2.46, P = 0.012) and low LMR (HR 1.65, 95 % CI 1.06 to 2.58, P = 0.026) were independent predictors of poor prognosis. NLR ≥ 5 and LMR < 3 correlated with an approximately twofold decrease in counts of helper and cytotoxic T cells, B cells, and NK cells. High NLR was also accompanied with increased neutrophil counts, while low LMR showed increased numbers of monocytes, mostly classical.

CONCLUSIONS

NLR and LMR may carry important prognostic information for patients with resected PDAC. The unfavorable prognosis likely correlates with reduced numbers of immune cells effective against the tumor and increased populations of cells involved in immune suppression.

Serum C-reactive protein acted as a prognostic biomarker for overall survival in metastatic prostate cancer patients

The aim of this study was to determine whether baseline serum C-reactive protein (CRP) levels were associated with overall survival in patients with metastatic prostate cancer in the Chinese population. A total of 135 patients with metastatic prostate cancer were retrospectively reviewed. Both Kaplan-Meier product-limit method and multivariable analysis by Cox regression model were used to assess the prognostic role of serum CRP levels on overall survival of patients with metastatic prostate cancer. There were 51 patients (37.8%) with higher values of baseline serum CRP levels (≥10 mg/L). Kaplan-Meier product-limit method and log-rank test showed that patients with high serum CRP level (≥10 mg/L) had significantly worse overall survival than those patients with normal serum CRP level (<10 mg/L) (P < 0.001). The multivariable analysis by Cox regression model further showed that high serum CRP level (≥10 mg/L) was a significantly independent predictor of overall survival (hazard ratio (HR) = 2.39; 95% confidence interval (95% CI) 1.56-2.39, P < 0.001). In addition, high Gleason score (≥8) also was an independent predictor of overall survival (HR = 1.80; 95% CI 1.16-2.79, P = 0.008). In conclusion, serum CRP level is useful to predict the prognosis of metastatic prostate cancer patients, and high serum CRP level is a significantly independent predictor of worse overall survival.

Circulating serum sVCAM-1 concentration in advanced ovarian cancer patients: correlation with concentration in ascites

Background

Vascular cell adhesion molecule-1 (VCAM-1) is associated with ovarian cancer progression but the origin of its soluble form (sVCAM-1) in serum is not well investigated. The purpose of this study was to elucidate whether the concentration of sVCAM-1 in serum correlates with the concentration in ascites, that represents local tumour environment, and with systemic inflammation, various clinicopathological characteristics, and patient outcome.

Patients and methods.

Thirty-six patients with advanced ovarian cancer were included in the study. Serum for sVCAM-1 analysis was obtained prior to surgery. Ascites samples were collected at the beginning of the operation. Clinical data were collected from patients’ medical records. sVCAM-1 in samples was analysed by flow cytometric bead-based assay. The mean follow-up period was 11 months (range 0–23) from the time of surgery.

Results

Serum sVCAM-1 concentrations are positively correlated to ascites sVCAM-1 concentrations. There was a weakly positive correlation of serum sVCAM-1 with tumour size and no correlation with inflammatory tumour markers, FIGO stage or grade. Higher concentrations of sVCAM-1 were associated with poor disease outcome (death from ovarian cancer) in almost all cases before chemotherapy was started.

Conclusions

This is the first study demonstrating that serum concentrations of sVCAM-1 in advanced ovarian cancer patients correlate with sVCAM-1 concentrations in ascites, thus expressing the biologic potential of malignant disease to metastasis, rather than systemic inflammation. Higher serum and ascites sVCAM-1 concentrations might have predictive potential for different biologic behaviour.

Methylated DNA and high total DNA levels in the serum of patients with breast cancer following neoadjuvant chemotherapy are predictive of a poor prognosis

In a previous study, we established a one-step methylation-specific polymerase chain reaction (OS-MSP) assay for the detection of methylated DNA (met-DNA) and total DNA levels in serum. For the present study, this OS-MSP assay was used for patients with breast cancer treated with neoadjuvant chemotherapy (NAC) in order to investigate the prognostic significance of met-DNA and total DNA levels. Following treatment with NAC and prior to surgery, serum samples obtained from 120 patients with stage II/III breast cancer were subjected to the OS-MSP assay for analysis of the glutathione S-transferase pi 1, Ras association (RalGDS/AF-6) domain family member 1 and retinoic acid receptor β2 genes. The detection of methylation in a minimum of one of these genes indicated a positive outcome of the assay. The total DNA content of the serum was also determined. Of the 120 stage II/III patients, seven (6%) were positive for met-DNA in serum and showed a significantly worse overall survival (OS) time compared with patients negative for met-DNA (n=113) (5-year OS, 43 vs. 85%; P=0.002). The patients with high total DNA levels in serum (n=40) also showed a significantly worse OS compared with those with low total DNA levels (n=80) (65 vs. 91%; P<0.001). The presence of met-DNA and high total DNA levels in the serum were found to be significant prognostic factors that are independent of a pathological complete response by multivariate analysis. Following NAC, met-DNA and high total DNA levels in the serum detected with the OS-MSP assay constitute novel prognostic factors for patients with breast cancer; this may be clinically useful for the prognosis prediction for patients who do not achieve a pathological complete response following NAC.

Detection of EpCAM-Negative and Cytokeratin-Negative Circulating Tumor Cells in Peripheral Blood

Enrichment of rare circulating tumor cells (CTCs) in blood is typically achieved using antibodies to epithelial cell adhesion molecule (EpCAM), with detection using cytokeratin (CK) antibodies. However, EpCAM and CK are not expressed in some tumors and can be downregulated during epithelial-to-mesenchymal transition. A micro-fluidic system, not limited to EpCAM or CK, was developed to use multiple antibodies for capture followed by detection using CEE-Enhanced (CE), a novel in situ staining method that fluorescently labels the capture antibodies bound to CTCs. Higher recovery of CTCs was demonstrated using antibody mixtures compared to anti-EpCAM. In addition, CK-positive breast cancer cells were found in 15 of 24 samples (63%; range 1–60 CTCs), while all samples contained additional CE-positive cells (range 1–41; median = 11; P = .02). Thus, antibody mixtures against a range of cell surface antigens enables capture of more CTCs than anti-EpCAM alone and CE staining enables the detection of CK-negative CTCs.