Expression of the CXCR4 ligand SDF-1/CXCL12 is prognostically important for adenocarcinoma and large cell carcinoma of the lung

Energy metabolism as the hub of advanced non-small cell lung cancer management: a comprehensive view in the framework of predictive, preventive, and personalized medicine

Energy metabolism is a hub of governing all processes at cellular and organismal levels such as, on one hand, reparable vs. irreparable cell damage, cell fate (proliferation, survival, apoptosis, malignant transformation etc.), and, on the other hand, carcinogenesis, tumor development, progression and metastazing versus anti-cancer protection and cure. The orchestrator is the mitochondria who produce, store and invest energy, conduct intracellular and systemically relevant signals decisive for internal and environmental stress adaptation, and coordinate corresponding processes at cellular and organismal levels. Consequently, the quality of mitochondrial health and homeostasis is a reliable target for health risk assessment at the stage of reversible damage to the health followed by cost-effective personalized protection against health-to-disease transition as well as for targeted protection against the disease progression (secondary care of cancer patients against growing primary tumors and metastatic disease). The energy reprogramming of non-small cell lung cancer (NSCLC) attracts particular attention as clinically relevant and instrumental for the paradigm change from reactive medical services to predictive, preventive and personalized medicine (3PM). This article provides a detailed overview towards mechanisms and biological pathways involving metabolic reprogramming (MR) with respect to inhibiting the synthesis of biomolecules and blocking common NSCLC metabolic pathways as anti-NSCLC therapeutic strategies. For instance, mitophagy recycles macromolecules to yield mitochondrial substrates for energy homeostasis and nucleotide synthesis. Histone modification and DNA methylation can predict the onset of diseases, and plasma C7 analysis is an efficient medical service potentially resulting in an optimized healthcare economy in corresponding areas. The MEMP scoring provides the guidance for immunotherapy, prognostic assessment, and anti-cancer drug development. Metabolite sensing mechanisms of nutrients and their derivatives are potential MR-related therapy in NSCLC. Moreover, miR-495-3p reprogramming of sphingolipid rheostat by targeting Sphk1, 22/FOXM1 axis regulation, and A2 receptor antagonist are highly promising therapy strategies. TFEB as a biomarker in predicting immune checkpoint blockade and redox-related lncRNA prognostic signature (redox-LPS) are considered reliable predictive approaches. Finally, exemplified in this article metabolic phenotyping is instrumental for innovative population screening, health risk assessment, predictive multi-level diagnostics, targeted prevention, and treatment algorithms tailored to personalized patient profiles-all are essential pillars in the paradigm change from reactive medical services to 3PM approach in overall management of lung cancers. This article highlights the 3PM relevant innovation focused on energy metabolism as the hub to advance NSCLC management benefiting vulnerable subpopulations, affected patients, and healthcare at large.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13167-024-00357-5.

The clinicopathological and prognostic value of CXCR4 expression in patients with lung cancer: a meta-analysis

Background

The C-X-C chemokine receptor 4 (CXCR4) has been suggested to play an important role in several types of cancers and is related to biological behaviors connected with tumor progression. However, the clinical significance and application of CXCR4 in lung cancer remain disputable. Thus, we conducted a meta-analysis to investigate the impact of CXCR4 expression on survival and clinicopathological features in lung cancer.

Methods

Comprehensive literature searches were conducted in PubMed, Embase and Web of Science for relevant studies. We pooled hazard ratios (HRs)/odds ratios (ORs) with 95% confidence intervals (CIs) by STATA 12.0 to evaluate the potential value of CXCR4 expression.

Results

Twenty-seven relevant articles involving 2932 patients with lung cancer were included in our meta-analysis. The results revealed that CXCR4 expression was apparently associated with poor overall survival (OS) (HR 1.61, 95% CI 1.42–1.82) and disease-free survival (HR 3.39, 95% CI 2.38–4.83). Furthermore, a significant correlation with poor OS was obvious in non-small cell lung cancer patients (HR 1.59, 95% CI 1.40–1.81) and in patients showing CXCR4 expression in the cytoplasm (HR 2.10, 95% CI 1.55–2.84) and the membrane (HR 1.74, 95% CI 1.24–2.45). CXCR4 expression was significantly associated with men (OR 1.32, 95% CI 1.08–1.61), advanced tumor stages (T3-T4) (OR 2.34, 95% CI 1.28–4.28), advanced nodal stages (N > 0) (OR 2.34, 95% CI 1.90–2.90), distant metastasis (OR 3.65, 95% CI 1.53–8.69), advanced TNM stages (TNM stages III, IV) (OR 3.10, 95% CI 1.95–4.93) and epidermal growth factor receptor (EGFR) expression (OR 2.44, 95% CI 1.44–4.12) but was not associated with age, smoking history, histopathology, differentiation, lymphatic vessel invasion or local recurrence.

Conclusion

High expression of CXCR4 is related to tumor progression and might be an adverse prognostic factor for lung cancer.

Functional Phenotypes of Peritoneal Macrophages Upon AMD3100 Treatment During Colitis-Associated Tumorigenesis

CXCL12 and its receptor CXCR4 are independent prognostic factors in colorectal cancer. AMD3100 is the most frequently used FDA-approved antagonist that targets the CXCL12-CXCR4 axis in clinical trials. We aimed to explore the role of AMD3100 and its effect on peritoneal macrophages' functional phenotypes during colitis-associated tumorigenesis. We treated AMD3100 in a colitis-associated colon cancer mouse model and evaluated its effect on tumorigenesis. The phagocytosis activities of peritoneal macrophages were measured by flow cytometry. The proportions of macrophages and M1/M2 subpopulations were investigated by flow cytometry, ELISA, and immunochemistry. Serum levels of pro-inflammatory and anti-inflammatory cytokines were measured by LEGENDplex™ kits. Transwell assay and qRT-PCR were performed to investigate the direct effect of CXCL12 on macrophages in vitro. We demonstrated that AMD3100 treatment reduced the inflammatory damages in the colonic mucosal and ameliorated tumor development in experimental mice. We found that the phagocytosis activities of peritoneal macrophages fluctuated during colitis-associated tumorigenesis. The proportions of peritoneal macrophages and M1/M2 subpopulations, together with their metabolite and cytokines, changed dynamically in the process. Moreover, AMD3100 regulated the functional phenotypes of macrophages, including reducing the recruiting activity, promoting polarization to the M1 subpopulation, and reducing IL-12 and IL-23 levels in serum. Our study contributes to understanding dynamic changes of peritoneal macrophages upon AMD3100 treatment during tumorigenesis and sheds light on the potential therapeutic target of AMD3100 and peritoneal macrophages against colitis-associated colon cancer.

Predictive and Prognostic Biomarkers for Lung Cancer Bone Metastasis and Their Therapeutic Value

Lung cancer is the leading cause of cancer-related death worldwide. Bone metastasis, which usually accompanies severe skeletal-related events, is the most common site for tumor distant dissemination and detected in more than one-third of patients with advanced lung cancer. Biopsy and imaging play critical roles in the diagnosis of bone metastasis; however, these approaches are characterized by evident limitations. Recently, studies regarding potential biomarkers in the serum, urine, and tumor tissue, were performed to predict the bone metastases and prognosis in patients with lung cancer. In this review, we summarize the findings of recent clinical research studies on biomarkers detected in samples obtained from patients with lung cancer bone metastasis. These markers include the following: (1) bone resorption-associated markers, such as N-terminal telopeptide (NTx)/C-terminal telopeptide (CTx), C-terminal telopeptide of type I collagen (CTx-I), tartrate-resistant acid phosphatase isoform 5b (TRACP-5b), pyridinoline (PYD), and parathyroid hormone related peptide (PTHrP); (2) bone formation-associated markers, including total serum alkaline phosphatase (ALP)/bone specific alkaline phosphatase(BAP), osteopontin (OP), osteocalcin (OS), amino-terminal extension propeptide of type I procollagen/carboxy-terminal extension propeptide of type I procollagen (PICP/PINP); (3) signaling markers, including epidermal growth factor receptor/Kirsten rat sarcoma/anaplastic lymphoma kinase (EGFR/KRAS/ALK), receptor activator of nuclear factor κB ligand/receptor activator of nuclear factor κB/osteoprotegerin (RANKL/RANK/OPG), C-X-C motif chemokine ligand 12/C-X-C motif chemokine receptor 4 (CXCL12/CXCR4), complement component 5a receptor (C5AR); and (4) other potential markers, such as calcium sensing receptor (CASR), bone sialoprotein (BSP), bone morphogenetic protein 2 (BMP2), cytokeratin 19 fragment/carcinoembryonic antigen (CYFRA/CEA), tissue factor, cell-free DNA, long non-coding RNA, and microRNA. The prognostic value of these markers is also investigated. Furthermore, we listed some clinical trials targeting hotspot biomarkers in advanced lung cancer referring for their therapeutic effects.

Cluster Analysis According to Immunohistochemistry is a Robust Tool for Non-Small Cell Lung Cancer and Reveals a Distinct, Immune Signature-defined Subgroup

Clustering in medicine is the subgrouping of a cohort according to specific phenotypical or genotypical traits. For breast cancer and lymphomas, clustering by gene expression profiles has already resulted in important prognostic and predictive subgroups. For non-small cell lung cancer (NSCLC), however, little is known. We performed a cluster analysis on a cohort of 365 surgically resected, well-documented NSCLC patients, which was followed-up for a median of 62 months, incorporating 70 expressed proteins and several genes. Our data reveal that tumor grading by architecture is significant, that large cell carcinoma is likely not a separate entity, and that an immune signature cluster exists. For squamous cell carcinomas, a prognostically relevant cluster with poorer outcome was found, defined by a high CD4/CD8 ratio and lower presence of granzyme B+ tumor-infiltrating lymphocytes (TIL). This study shows that clustering analysis is a useful tool for verifying established characteristics and generating new insights for NSCLC. Importantly, for one "immune signature" cluster, the signature of the TIL (especially the amount of CD8+ TIL) was more crucial than the histologic or any other phenotypical aspect. This may be an important finding toward explaining why only a fraction of eligible patients respond to immunomodulating anticancer therapies.

CXCR4/ACKR3/CXCL12 axis in the lymphatic metastasis of vulvar squamous cell carcinoma

Aims

Vulvar squamous cell carcinoma (VSCC) spreads early and mainly locally via direct expansion into adjacent structures, followed by lymphatic metastasis to the regional lymph nodes (LNs). In the lymphatic metastasis, cancer cells bearing CXCR4 and ACKR3 (CXCR7) receptors are recruited to the LNs that produce the CXCL12 ligand. Our study aimed to assess the role of the CXCR4/ACKR3/CXCL12 axis in VSCC progression.

Methods

Tumour and LN tissue samples were obtained from 46 patients with VSCC and 51 patients with premalignant vulvar lesions. We assessed CXCR4, ACKR3 and CXCL12 by immunohistochemistry (IHC) in the tissue samples. Additionally, CXCL12 levels were determined by ELISA in the sera of 23 patients with premalignant lesions, 37 with VSCC and 16 healthy volunteers.

Results

CXCR4 and ACKR3 proteins were virtually absent in vulvar precancers, while in VSCC samples the IHC staining was strong. In the LNs of patients with VSCC, 98% of metastatic cells expressed CXCR4 and 85% expressed ACKR3. Neither CXCR4 nor ACKR3 presence was correlated with tumour human papilloma virus status. Few CXCL12-positive cells were found in the analysed tissue samples, but serum CXCL12 levels were significantly increased in both patients with premalignant vulvar lesions and with VSCC compared with healthy volunteers.

Conclusions

It appears that during progression and lymphatic spread of VSCC, the CXCR4/ACKR3/CXCL12 axis is activated. Moreover, our data suggest that CXCR4 antagonists merit further attention as a possible therapeutic option in patients with VSCC.

Prognostic significance of CD8+ T-cells density in stage III colorectal cancer depends on SDF-1 expression

Since colorectal cancer (CRC) remains one of the most common malignancies, a tremendous amount of studies keep taking place in this field. Over the past 25 years, a notable part of the scientific community has focused on the association between the immune system and colorectal cancer. A variety of studies have shown that high densities of infiltrating CD8+ T-cells are associated with improved disease-free and overall survival in CRC. Stromal cell-derived factor-1 (SDF-1) is a protein that regulates leukocyte trafficking and is variably expressed in several healthy and malignant tissues. There is strong evidence that SDF-1 has a negative prognostic impact on a variety of solid tumors. However, the existing data do not provide sufficient evidence that the expression of SDF-1 has an influence on CRC. Knowing nowadays, that the microenvironment plays a crucial role in the development of cancer, we hypothesized that the expression of SDF-1 in CRC could influence the prognostic significance of CD8+ T-cells, as an indicator of the essential role of the immune microenvironment in cancer development. Therefore, we explored the combined prognostic significance of CD8+ T-cell density and SDF-1 expression in a large CRC collective. We analyzed a tissue microarray of 613 patient specimens of primary CRCs by immunohistochemistry (IHC) for the CD8 + T-cells density and the expression of SDF-1 by tumor cells and tumor-infiltrating immune cells. Besides, we analyzed the expression of SDF-1 at the RNA level in The Cancer Genome Atlas cohort. We found that the combined high CD8+ T-cell infiltration and expression of SDF-1 shows a favorable 5-year overall survival rate (66%; 95% CI 48-79%) compared to tumors showing a high expression of CD8+ T-cell only (55%; 95% CI 45-64%; p = 0.0004). After stratifying the patients in nodal negative and positive groups, we found that the prognostic significance of CD8+ T-cell density in nodal positive colorectal cancer depends on SDF-1 expression. Univariate and multivariate Hazard Cox regression survival analysis considering the combination of both markers revealed that the combined high expression of SDF-1 and CD8+ T-cell density was an independent, favorable, prognostic marker for overall survival (HR = 0.34, 95% CI 0.17-0.66; p = 0.002 and HR = 0.45, 95% CI 0.23-0.89; p = 0.021, respectively). In our cohort there was a very weak correlation between SDF-1 and CD8+ T-cells (rs = 0.13, p = 0.002) and in the trascriptomic expression of these two immune markers display a weak correlation (rs = 0.28, p < 0.001) which was significantly more pronounced in stage III cancers (rs = 0.40, p < 0.001). The combination of high CD8+ T-cell density and expression of SDF-1 represents an independent, favorable, prognostic condition in CRC, mostly in patients with stage III disease.

The CXCL12-CXCR4 Signaling Axis Plays a Key Role in Cancer Metastasis and is a Potential Target for Developing Novel Therapeutics against Metastatic Cancer

Metastasis is the main cause of death in cancer patients; there is currently no effective treatment for cancer metastasis. This is primarily due to our insufficient understanding of the metastatic mechanisms in cancer. An increasing number of studies have shown that the C-X-C motif chemokine Ligand 12 (CXCL12) is overexpressed in various tissues and organs. It is a key niche factor that nurtures the pre-metastatic niches (tumorigenic soil) and recruits tumor cells (oncogenic "seeds") to these niches, thereby fostering cancer cell aggression and metastatic capabilities. However, the C-X-C motif chemokine Receptor 4 (CXCR4) is aberrantly overexpressed in various cancer stem/progenitor cells and functions as a CXCL12 receptor. CXCL12 activates CXCR4 as well as multiple downstream multiple tumorigenic signaling pathways, promoting the expression of various oncogenes. Activation of the CXCL12-CXCR4 signaling axis promotes Epithelial-Mesenchymal Transition (EMT) and mobilization of cancer stem/progenitor cells to pre-metastatic niches. It also nurtures cancer cells with high motility, invasion, and dissemination phenotypes, thereby escalating multiple proximal or distal cancer metastasis; this results in poor patient prognosis. Based on this evidence, recent studies have explored either CXCL12- or CXCR4-targeted anti-cancer therapeutics and have achieved promising results in the preclinical trials. Further exploration of this new strategy and its potent therapeutics effect against metastatic cancer through the targeting of the CXCL12- CXCR4 signaling axis may lead to a novel therapy that can clean up the tumor microenvironment ("soil") and kill the cancer cells, particularly the cancer stem/progenitor cells ("seeds"), in cancer patients. Ultimately, this approach has the potential to effectively treat metastatic cancer.

AMD3100 inhibits epithelial-mesenchymal transition, cell invasion, and metastasis in the liver and the lung through blocking the SDF-1α/CXCR4 signaling pathway in prostate cancer

Stromal cell-derived factor-1 (SDF-1) and CXC chemokine receptor 4 (CXCR4) have been found to be tightly correlated with the progression of prostate cancer (PC). In this study, we investigated the effects of an SDF-1α/CXCR4 inhibitor, AMD3100, on cell progression and metastasis potential of human PC cells. Human PC cell lines (LNCaP, PC3, and DU145) were cultured to detect SDF-1α/CXCR4, which showed higher SDF-1α and CXCR4 expression than the normal human prostate epithelial cell line, RWPE-1. AMD3100 was confirmed to be an inhibitor of SDF-1α, and to detect the effect of SDF-1α/CXCR4 inhibition on PC, PC cells were treated with AMD3100 or/and CXCR4 siRNA. The results suggested that inhibition of the SDF-1α/CXCR4 pathway could promote the E-cadherin level but inhibit the levels of invasion and migration of vimentin, N-cadherin and α5β1 integrin. Finally, tumor formation in nude mice was conducted, and the cell experiment results were verfied. These data show that AMD3100 suppresses epithelial-mesenchymal transition and migration of PC cells by inhibiting the SDF-1α/CXCR4 signaling pathway, which provides a clinical target in the treatment of PC.

Diagnostic and prognostic impact of mucin 1-6 expression in non-small cell lung cancer

Background

The prognostic significance and clinico-pathological characterization of mucin (MUC) expression in non-small cell lung cancer (NSCLC) is controversial and little studied.

Aims

This study aims at elucidating this issue on the largest and most detailed cohort so far.

Settings and Design

We examined the expression of MUC 1, 2, 4, 5AC and 6 on 371, well documented, surgically resected NSCLC cases.

Materials and Methods

Immunohistochemical results were correlated with several of our previously studied, relevant parameters on this cohort including a follow-up period of up to 20 years. An additional point we examined for practical reasons that has not been addressed so far, was the possible assistance of MUC expression for the differentiation between a primary lung adenocarcinoma and metastasis from a known pancreatobiliary primary tumor.

Statistical Analysis Used

Cronbach's Alpha reliability correlation, Spearman's correlation, ANOVA means of comparison with additional Kruskall-Wallis H-test, and Kaplan-Meier survival analysis were employed as statistical analyses in this study.

Results and Conclusions

MUCs were associated with histologic subtypes, tumor differentiation and members of the epidermal growth factor receptor signaling pathway, although they were not found to be significant for prognosis. Expression of MUC1 correlated with certain other markers and may point to a group of patients relevant for upcoming treatment strategies involving MUC1. According to our findings, we also recommend additional MUC5AC staining for a thyroid transcription factor 1-negative adenocarinoma in the lung for the differentiation of a possible metastasis in the presence of a pancreatic ductal adenocarcinoma.

CXCR4 Based Therapeutics for Non-Small Cell Lung Cancer (NSCLC)

Lung cancer is the second most common malignancy. Unfortunately, despite advances in multimodality therapeutics for the disease, the overall five-year survival rate among newly diagnosed lung cancer patients remains in the range region of 15%. In addition, although immune checkpoint inhibitors are increasingly being incorporated into lung cancer treatment protocols, the proportion of patients that respond to these agents remains low and the duration of response is often short. Therefore, novel methodologies to enhance the efficacy of immunotherapy in lung cancer are highly desirable. Chemokines are small chemotactic cytokines that interact with their 7 transmembrane G-protein⁻coupled receptors, to guide immune cell trafficking in the body under both physiologic and pathologic conditions. Tumor cells highjack a small repertoire of the chemokine/chemokine receptor system and utilize it in a manner that benefits local tumor growth and distant spread. The chemokine receptor, CXCR4 is expressed in over 30 types of malignant tumors and, through interaction with its ligand CXCL12, was shown exert pleotropic pro-tumorigenic effects. In this review, the pathologic roles that CXCL12/CXCR4 play in lung cancer propagation are presented. Furthermore, the challenges and potential benefits of incorporating drugs that target CXCL12/CXCR4 into immune-based lung cancer therapeutic protocols are discussed.

Tenascin‑C promotes the migration of bone marrow stem cells via toll‑like receptor 4‑mediated signaling pathways: MAPK, AKT and Wnt

There are currently limitations in stem cell therapy due to the low rate of homing and proliferation of cells following transplantation. The present study was designed to investigate the effects of Tenascin-C (TN-C) on bone marrow mesenchymal stem cells (BMSCs) and its underlying mechanisms. BMSCs were obtained from C57BL/6 mice. The survival and proliferation of BMSCs was analyzed by Cell Counting Kit-8 assay, migration was evaluated using the Transwell method, and differentiation was assessed by immunocytochemistry and immunofluorescence. In addition, the levels of proteins were detected by western blotting. High concentrations of TN-C promoted the migration of BMSCs. H₂O₂ at concentrations of 60–90 µmol/ml induced cell death in BMSCs, and thus, it was used to simulate oxidative stress in the microenvironment of acute myocardial infarction (AMI). High concentrations of TN-C were able to protect BMSCs from cell death, and promoted the migration of BMSCs (P<0.05). However, TAK-242 [the inhibitor of Toll-like receptor 4, (TLR4)] reduced the promoting effect of TN-C (P<0.05). By contrast, TN-C had no effect on the proliferation and differentiation of BMSCs. TN-C reduced the phosphorylation levels of p38 mitogen-activated protein kinase (MAPK), and increased the phosphorylation levels of Ser473 protein kinase B (AKT) and β-catenin, all of which were inhibited by TAK-242 (P<0.05). In the simulated AMI microenvironment, TN-C promoted the migration of BMSCs via TLR4-mediated signaling pathways, including MAPK, AKT and Wnt.

Alcohol-Mediated Organ Damages: Heart and Brain

Alcohol is one of the most commonly abused substances in the United States. Chronic consumption of ethanol has been responsible for numerous chronic diseases and conditions globally. The underlying mechanism of liver injury has been studied in depth, however, far fewer studies have examined other organs especially the heart and the central nervous system (CNS). The authors conducted a narrative review on the relationship of alcohol with heart disease and dementia. With that in mind, a complex relationship between inflammation and cardiovascular disease and dementia has been long proposed but inflammatory biomarkers have gained more attention lately. In this review we examine some of the consequences of the altered cytokine regulation that occurs in alcoholics in organs other than the liver. The article reviews the potential role of inflammatory markers such as TNF-α in predicting dementia and/or cardiovascular disease. It was found that TNF-α could promote and accelerate local inflammation and damage through autocrine/paracrine mechanisms. Unraveling the mechanisms linking chronic alcohol consumption with proinflammatory cytokine production and subsequent inflammatory signaling pathways activation in the heart and CNS, is essential to improve our understanding of the disease and hopefully facilitate the development of new remedies.

Phosphorylated CXCR4 expression has a positive prognostic impact in colorectal cancer

BACKGROUND

The CXCL12-CXCR4 chemokine axis plays an important role in cell trafficking as well as in tumor progression. In colorectal cancer (CRC), the chemokine receptor CXCR4 has been shown to be an unfavorable prognostic factor in some studies, however, the role of its activated (phosphorylated) form, pCXCR4, has not yet been evaluated. Here, we aimed to investigate the prognostic value of CXCR4 and pCXCR4 in a large cohort of CRC patients.

PATIENTS AND METHODS

A tissue microarray (TMA) of 684 patient specimens of primary CRCs was analyzed by immunohistochemistry (IHC) for the expression of CXCR4 and pCXCR4 by tumor cells and tumor-infiltrating immune cells (TICs).

RESULTS

The combined high expression of CXCR4 and pCXCR4 showed a favorable 5-year overall survival rate (68%; 95%CI = 59-76%) compared to tumors showing a high expression of CXCR4 only (48%; 95%CI = 41-54%). High expression of pCXCR4 was significantly associated with a favorable prognosis in a test and validation group (p = 0.015 and p = 0.0001). Moreover, we found that CRCs with a high density of pCXCR4+ tumor-infiltrating immune cells (TICs) also showed a favorable prognosis in a test and validation group (p = 0.054 and p = 0.004). Univariate Cox regression analysis for TICs revealed that a high density of pCXCR4+ TICs was a favorable prognostic marker for overall survival (HR = 0.97,95%CI = 0.96-1.00; p = 0.01). In multivariate Cox regression survival analyses a high expression of pCXCR4 in tumor cells lost its association with a better overall survival (HR = 0.99; 95%CI = 0.99-1.00, p = 0.098).

CONCLUSION

Our results show that high densities of CXCR4 and pCXCR4 positive TICs are favorable prognostic factors in CRC.

A meta-analysis of CXCL12 expression for cancer prognosis

Background:

CXCL12 (SDF1) is reported to promote cancer progression in several preclinical models and this is corroborated by the analysis of human tissue specimens. However, the relationship between CXCL12 expression and cancer survival has not been systematically assessed.

Methods:

We conducted a systematic review and meta-analysis of studies that evaluated the association between CXCL12 expression and cancer survival.

Results:

Thirty-eight studies inclusive of 5807 patients were included in the analysis of overall, recurrence-free or cancer-specific survival, the majority of which were retrospective. The pooled hazard ratios (HRs) for overall and recurrence-free survival in patients with high CXCL12 expression were 1.39 (95% CI: 1.17–1.65, P=0.0002) and 1.12 (95% CI: 0.82–1.53, P=0.48) respectively, but with significant heterogeneity between studies. On subgroup analysis by cancer type, high CXCL12 expression was associated with reduced overall survival in patients with oesophagogastric (HR 2.08; 95% CI: 1.31–3.33, P=0.002), pancreatic (HR 1.54; 95% CI: 1.21–1.97, P=0.0005) and lung cancer (HR 1.37; 95% CI: 1.08–1.75, P=0.01), whereas in breast cancer patients high CXCL12 expression conferred an overall survival advantage (HR 0.5; 95% CI: 0.38–0.66, P<0.00001).

Conclusions:

Determination of CXCL12 expression has the potential to be of use as a cancer biomarker and adds prognostic information in various cancer types. Prospective or prospective–retrospective analyses of CXCL12 expression in clearly defined cancer cohorts are now required to advance our understanding of the relationship between CXCL12 expression and cancer outcome.