CXCR3-B Expression Correlates With Tumor Necrosis Extension in Renal Cell Carcinoma

The Role of CXCL11 and its Receptors in Cancer: Prospective but Challenging Clinical Targets

Chemokine ligand 11 is a member of the CXC chemokine family and exerts its biological function mainly through binding to CXCR3 and CXCR7. The CXCL11 gene is ubiquitously overexpressed in various human malignant tumors; however, its specific mechanisms vary among different cancer types. Recent studies have found that CXCL11 is involved in the activation of multiple oncogenic signaling pathways and is closely related to tumorigenesis, progression, chemotherapy tolerance, immunotherapy efficacy, and poor prognosis. Depending on the specific expression of its receptor subtype, CXCL11 also has a complex 2-fold role in tumours; therefore, directly targeting the structure-function of CXCL11 and its receptors may be a challenging task. In this review, we summarize the biological functions of CXCL11 and its receptors and their roles in various types of malignant tumors and point out the directions for clinical applications.

CXCR3 isoform A promotes head and neck cancer progression by enhancing stem-like property and chemoresistance

The chemokine network orchestrates the cancer stem-like property and consequently participates in cancer progression. CXCR3 contributes cancer progressive property and immunomodulation in the tumor microenvironment. The two major isoforms of CXCR3 are scrutinized and the divergence is showed that CXCR3A promotes cancer cell growth and motility while CXCR3B functions contrarily in many studies. However, rare studies illustrate the role of CXCR3 isoforms in cancer stem-like property and chemoresistance, especially in head and neck cancer (HNC). First, we used immunohistochemistry staining to evaluate expression levels of CXCR3, CXCR3B, and Sox2 cancer stem cell (CSC) marker and association with tumor progression in HNC tissues. Results showed that high levels of CXCR3 were significantly associated with advanced stage (p <0.01), regional lymph node metastasis (p <0.05), and poor differentiation (p <0.005) and further correlated with worse survival rate in oral cancer patients (p = 0.036). Higher levels of CXCR3B were found in regional lymphatic invasion of HNC and progressive stage of squamous cell carcinoma. Elevated Sox2 expression was significantly associated with the advanced stage of HNC in the oral cavity, and demonstrated a co-expression pattern with CXCR3B. Furthermore, lentivirus-mediated overexpression of CXCR3A and CXCR3B in SAS human oral cancer cells promoted cell mobility. CXCR3A overexpression enhanced sphere-forming ability and chemoresistance of CSCs by upregulating stemness-related genes. This study first provides a novel insight of CXCR3 isoform A in HNC cancer progression via regulating cancer stem-like properties and chemoresistance, suggesting that CXCR3A may be a prognostic marker and novel target for HNC therapy.

Salvage Endoscopic Nasopharyngectomy in Recurrent Nasopharyngeal Carcinoma: Prognostic Factors and Treatment Outcomes

BACKGROUND

This study aimed to investigate the demographics, treatment outcomes, and prognostic factors of salvage endoscopic nasopharyngectomy in recurrent nasopharyngeal carcinoma (NPC).

METHODS

We conducted a retrospective analysis of 189 patients who underwent treatment for recurrent NPC from January 2006 to June 2018. The Kaplan-Meier method and log-rank test were used to assess survival rates. A Cox regression model was used for multivariate survival analyses.

RESULTS

We included 132 men and 57 women in the study, with a median age of 51 (range, 25-85) years. The overall 1-, 3-, and 5-year survival rates were 82.2%, 59.5%, and 43.6%, respectively, during a median follow-up of 24 (range, 2-111) months. In subjects over 50 years of age, diabetes, low body mass index (BMI < 20 kg/m²), low hemoglobin (<120 g/l) levels, increased neutrophil to lymphocyte ratio (NLR; ≥ 6), advanced T stage (rT3 and rT4), lymph node metastasis, and positive surgical margins were associated with a poor prognosis in terms of overall survival. Cox multivariate regression analyses showed significant differences in age, BMI, NLR, diabetes, T stage, N stage, and tumor necrosis.

CONCLUSIONS

In subjects over 50 years of age, diabetes, low BMI, increased NLR, advanced T stage, lymph node metastasis, and tumor necrosis were independent prognostic factors for overall survival.

The Distinct Roles of CXCR3 Variants and Their Ligands in the Tumor Microenvironment

First thought to orchestrate exclusively leukocyte trafficking, chemokines are now acknowledged for their multiple roles in the regulation of cell proliferation, differentiation, and survival. Dysregulation of their normal functions contributes to various pathologies, including inflammatory diseases and cancer. The two chemokine receptor 3 variants CXCR3-A and CXCR3-B, together with their cognate chemokines (CXCL11, CXCL10, CXCL9, CXCL4, and CXCL4L1), are involved in the control but also in the development of many tumors. CXCR3-A drives the infiltration of leukocytes to the tumor bed to modulate tumor progression (paracrine axis). Conversely, tumor-driven changes in the expression of the CXCR3 variants and their ligands promote cancer progression (autocrine axis). This review summarizes the anti- and pro-tumoral activities of the CXCR3 variants and their associated chemokines with a focus on the understanding of their distinct biological roles in the tumor microenvironment.

Differential expression profile of CXCR3 splicing variants is associated with thyroid neoplasia. Potential role in papillary thyroid carcinoma oncogenesis?

Papillary thyroid cancer (PTC) is the most prevalent endocrine neoplasia. The increased incidence of PTC in patients with thyroiditis and the frequent immune infiltrate found in PTC suggest that inflammation might be a risk factor for PTC development. The CXCR3-ligand system is involved in thyroid inflammation and CXCR3 has been found upregulated in many tumors, suggesting its pro-tumorigenic role under the inflammatory microenvironment. CXCR3 ligands (CXCL4, CXCL9, CXCL10 and CXCL11) trigger antagonistic responses partly due to the presence of two splice variants, CXCR3A and CXCR3B. Whereas CXCR3A promotes cell proliferation, CXCR3B induces apoptosis. However, the relation between CXCR3 variant expression with chronic inflammation and PTC development remains unknown. Here, we characterized the expression pattern of CXCR3 variants and their ligands in benign tumors and PTC. We found that CXCR3A and CXCL10 mRNA levels were increased in non-metastatic PTC when compared to non-neoplastic tissue. This increment was also observed in a PTC epithelial cell line (TPC-1). Although elevated protein levels of both isoforms were detected in benign and malignant tumors, the CXCR3A expression remained greater than CXCR3B and promoted proliferation in Nthy-ori-3-1 cells. In non-metastatic PTC, inflammation was conditioning for the CXCR3 ligands increased availability. Consistently, CXCL10 was strongly induced by interferon gamma in normal and tumor thyrocytes.

Our results suggest that persistent inflammation upregulates CXCL10 expression favoring tumor development via enhanced CXCR3A-CXCL10 signaling. These findings may help to further understand the contribution of inflammation as a risk factor in PTC development and set the basis for potential therapeutic studies.

Prognostic Significance of Tumor Necrosis in Hilar Cholangiocarcinoma

BACKGROUND

Tumor necrosis and peritumoral fibrosis have both been suggested to have a prognostic value in selected solid tumors. However, little is known regarding their influence on tumor progression and prognosis in hilar cholangiocarcinoma (HC).

METHODS

Surgically resected tumor specimens of HC (n = 47) were analyzed for formation of necrosis and extent of peritumoral fibrosis. Tumor necrosis and grade of fibrosis were assessed histologically and correlated with clinicopathological characteristics, tumor recurrence, and patients' survival. Univariate Kaplan-Meier analysis and a stepwise multivariable Cox regression model were applied.

RESULTS

Mild peritumoral fibrosis was evident in 12 tumor samples, moderate peritumoral fibrosis in 20, and high-grade fibrosis in 15. Necrosis was evident in 19 of 47 tumor samples. Patients with tumors characterized by necrosis showed a significantly decreased 5-year recurrence-free survival (37.9 vs. 25.7 %; p < .05) and a significantly decreased 5-year overall survival (42.6 vs. 12.4 %; p < .05), when compared with patients with tumors showing no necrosis. R status, tumor recurrence, and tumor necrosis were of prognostic value in the univariate analysis (all p < .05). Multivariate survival analysis confirmed tumor necrosis (p = .038) as the only independent prognostic variable.

CONCLUSIONS

The assessment of tumor necrosis appears as a valuable additional prognostic tool in routine histopathological evaluation of HC. These observations might have implications for monitoring and more individualized multimodal therapeutic strategies.

CXCR3A contributes to the invasion and metastasis of gastric cancer cells

CXCR3, belonging to CXC chemokine receptors, has been identified to be overexpressed in various kinds of tumors. There are three mRNA variants of CXCR3 (CXCR3A, CXCR3B and CXCR3alt) in human cells. The functions of major CXCR3 isoforms (CXCR3A, CXCR3B) have been reported in some tumors including prostate and breast cancer. However, the effects of CXCR3A and CXCR3B on gastric cancer cell progression remain unknown. The present investigation found that CXCR3A mRNA level was upregulated but CXCR3B mRNA level was downregulated in gastric cancer cells and tissues. In vitro growth analysis showed that CXCR3A acted as a positive mediator in regulating cell growth, whereas CXCR3B exerted the opposite effect. In vitro invasion and migration assays showed that CXCL10 promoted gastric cancer cell invasion and migration via CXCR3A, but not CXCR3B. Moreover, knockdown of CXCR3A inhibited cell growth and metastasis in vivo. Additionally, CXCR3A knockdown attenuated matrix metalloproteinase (MMP)‑13 and IL‑6 expression, and reduced ERK1/2 activation. Together, these data suggest that CXCR3A contributes to the growth, invasion and metastasis of gastric cancer cells in vitro and in vivo, and thus may be a key mediator of gastric cancer progression.

Overexpression of the chemokine receptor CXCR3 and its correlation with favorable prognosis in gastric cancer

Chemokine receptor, CXCR3, has been increasingly reported to be involved in tumorigenesis and tumor progression, but limited data are available regarding the expression of CXCR3 in gastric cancer (GC). In the present study, the expressions of CXCR3 and its variants were detected in 96 GC and corresponding nontumor gastric tissues by immunohistochemical staining, in 40 freshly frozen GC and nontumor gastric tissues by reverse-transcription polymerase chain reaction and quantitative real-time polymerase chain reaction, and in 10 freshly frozen GC and nontumor gastric tissues by Western blotting. Results revealed that an overexpression of CXCR3 occurs in GC tissues as compared to the nontumor gastric tissues. High level of CXCR3 expression was found to be inversely associated with invasion depth and metastasis (P = .030 and P = .019, respectively) and directly associated with improved overall survival (log-rank test, P < .001). Furthermore, multivariate analysis showed that high CXCR3 expression acts an independent prognostic factor for GC patients (hazard ratio, 0.379 [0.196-0.734]; P = .004). The messenger RNA expression of both the CXCR3 variants, CXCR3-A and CXCR3-B, were up-regulated in GC tissues (P = .006 and P = .002, respectively), although CXCR3-B messenger RNA expression was significantly higher than CXCR3-A, with an average CXCR3-B to CXCR3-A ratio of 1.80. CXCR3-B protein expression was also up-regulated in GC tissues (P = .023). In conclusion, our study suggested a potential use of CXCR3 overexpression as a prognostic marker for GC and involvement of the up-regulation of CXCR3-B in favorable prognosis of GC patients.

C-X-C ligand 10 and C-X-C receptor 3 status can predict tamoxifen treatment response in breast cancer patients

To investigate the expression levels of CXCL10 and CXCR3 in tumors from breast cancer patients randomized to adjuvant tamoxifen treatment or no endocrine treatment, in order to further study the connection to prognosis and prediction of tamoxifen treatment outcome. Immunohistochemistry on tissue microarrays from 912 breast cancer patients randomized to tamoxifen or no endocrine treatment. CXCR3 status was found to be a prognostic tool in predicting distant recurrence, as well as reduced breast cancer-specific survival. In patients with estrogen receptor (ER)-positive tumors, tumors with strong CXCL10 levels had improved effect of tamoxifen treatment in terms of local recurrence-free survival [risk ratio (RR) 0.46 (95 % CI 0.25–0.85, P = 0.01)] compared with patients with tumors expressing weak CXCL10 expression. Further, patients with ER-positive tumors with strong CXCR3 expression had an improved effect of tamoxifen in terms of breast cancer-specific survival [RR 0.34 (95 % CI 0.19–0.62, P < 0.001)] compared with the group with weak CXCR3 levels [RR 1.33 (95 % CI 0.38–4.79, P = 0.65)]. We show here for the first time that CXCL10 and CXCR3 expression are both predictors of favorable outcome in patients treated with tamoxifen.

The association of CXCR3 and renal cell carcinoma metastasis

PURPOSE

Renal cell carcinoma expresses CXCR3 but the function of CXCR3 in renal cell carcinoma has not been clarified. We explored the function of CXCR3 in renal cell carcinoma and investigated CXCR3 regulating factors.

MATERIALS AND METHODS

We obtained 56 clinical samples of clear cell renal cell carcinoma and corresponding normal renal tissue samples from the surgical specimens of Japanese patients who underwent radical nephrectomy at Chiba University Hospital between 2000 and 2011. As renal cell carcinoma cell lines, we used 786-O, ACHN and Caki-1. The expression profiles of CXCR3 and its splice variants were examined. For functional analyses 786-O and interferon-γ inducible 10 kDa protein or IP-10 (CXCL10) were selected as representatives.

RESULTS

CXCR3 and its ligands were abundant in renal cell carcinoma samples compared to corresponding normal kidney samples. The CXCR3-A-to-CXCR3-B ratio was 1.5 times higher in renal cell carcinoma samples than in normal kidney samples. CXCL10 treatment induced 786-O cell migration and invasion, and these effects were inhibited by neutralizing antibody. Phosphorylated RhoA and pro/active matrix metalloproteinase-9 expression was up-regulated by CXCL10 treatment. In clinical samples CXCR3 and CXCR3-A expression was significantly higher in metastatic than in nonmetastatic carcinoma samples. Finally, the expression of CXCR3-A and HIF-1α correlated significantly in clinical samples. In 786-O treatment with CoCl2 up-regulated CXCR3 and HIF-1α expression 4.5 and 2.2-fold, respectively.

CONCLUSIONS

We determined the association of CXCR3 and renal cell carcinoma metastasis. CXCR3 expression may be regulated by hypoxia.

A novel CXCR3-B chemokine receptor-induced growth-inhibitory signal in cancer cells is mediated through the regulation of Bach-1 protein and Nrf2 protein nuclear translocation

Chemokines and their receptors play diverse roles in regulating cancer growth and progression. The receptor CXCR3 can have two splice variants with opposite functions. CXCR3-A promotes cell growth, whereas CXCR3-B mediates growth-inhibitory signals. However, the negative signals through CXCR3-B in cancer cells are not well characterized. In this study, we found that CXCR3-B-mediated signaling in MCF-7 and T47D breast cancer cells induced apoptotic cell death. Signals through CXCR3-B decreased the levels of the antiapoptotic proteins Bcl-2 and Bcl-xL and increased the expression of apoptotic cleaved poly(ADP-ribose) polymerase. Along with up-regulation in apoptosis, CXCR3-B signals were associated with a decrease in cellular autophagy with reduced levels of the autophagic markers Beclin-1 and LC3B. Notably, CXCR3-B down-regulated the expression of the cytoprotective and antiapoptotic molecule heme oxygenase-1 (HO-1) at the transcriptional level. There was an increased nuclear localization of Bach-1 and nuclear export of Nrf2, which are important negative and positive transcription factors, respectively, for HO-1 expression. We also observed that CXCR3-B promoted the activation of p38 MAPK and the inhibition of ERK-1/2. CXCR3-B could not induce cancer cell apoptosis at the optimal level when we either inhibited p38 activity or knocked down Bach-1. Further, CXCR3-B-induced apoptosis was down-regulated when we overexpressed HO-1. Together, our data suggest that CXCR3-B mediates a growth-inhibitory signal in breast cancer cells through the modulations of nuclear translocation of Bach-1 and Nrf2 and down-regulation of HO-1. We suggest that the induction of CXCR3-B-mediated signaling can serve as a novel therapeutic approach where the goal is to promote tumor cell apoptosis.

The emerging role of CXC chemokines and their receptors in cancer

Chemokines and their receptors have a multifaceted role in tumor biology and are implicated in nearly all aspects of cancer growth, survival and dissemination. Modulation of the interaction between chemokines and their cell surface receptor is, therefore, a promising area for the development of new cancer medicines. In this review, we look at the compelling evidence that is emerging to support targeting CXC chemokines, also known as family α chemokines, as novel therapeutic strategies in the treatment of cancer.

The emerging role of CXC chemokines in epithelial ovarian cancer

In recent years, chemokines have generated intense investigations due to their involvement in both physiological and pathological processes of inflammation, particularly in ovarian biology. The physiological process of ovulation in the normal ovary involves various chemokines that mediate the healing of the ruptured endometrium. It is now being reported that many of these chemokines are also associated with the cancer of the ovary. Chronic inflammation underlies the progression of ovarian cancer; therefore, it raises the possibility that chemokines are involved in the inflammatory process and mediate immune responses that may favour or inhibit tumour progression. Ovarian cancer is a gynaecological cancer responsible for highest rate of mortality in women. Although there have been several investigations and advances in surgery and chemotherapy, the survival rate for this disease remains low. This is mainly because of a lack of specific symptoms and biomarkers for detection. In this review, we have discussed the emerging role of the CXC chemokines in epithelial ovarian cancer (EOC). The CXC group of chemokines is gaining importance in the field of ovarian cancer for being angiostatic and angiogenic in function. While there have been several studies on the angiogenesis function, emerging research shows that ELR(-) CXC chemokines, CXCL9 and CXCL10, are angiostatic. Importantly, the angiostatic chemokines can inhibit the progression of EOC. Given that there are currently no biomarkers or specific therapeutic targets for the disease, these chemokines are emerging as promising targets for therapy.

Histologic tumor necrosis is an independent prognostic indicator for clear cell and papillary renal cell carcinoma

Histologic tumor necrosis (TN) has been reported to indicate a poor prognosis for different human cancers. In papillary renal cell carcinoma (RCC), data regarding the prognostic impact of TN are conflicting. We retrospectively studied the pathology records of 2,333 consecutive patients who underwent nephrectomy from 1984 to 2006 at a single tertiary academic center. In multivariate analyses regarding clear cell RCC, the presence of histologic TN was an independent negative prognostic factor for metastasis-free (hazard ratio [HR], 2.32; confidence interval [CI], 1.86-2.9; P < .001) and overall (HR, 1.52; CI, 1.31-1.76; P < .001) survival. Regarding papillary RCC, the presence of histologic TN represented an independent predictor of metastasis-free (HR, 5.22; CI, 2.2-12.5; P < .001) and overall (HR, 1.69; CI, 1.11-2.58; P = .015) survival. Our findings suggest that the presence of TN is an independent predictor of clinical outcome in clear cell and papillary RCC. Thus, histologic TN might be a reliable prognostic indicator and should, therefore, routinely be examined during pathologic analysis of RCC specimens.

Altered CXCR3 isoform expression regulates prostate cancer cell migration and invasion

BACKGROUND

Carcinoma cells must circumvent the normally suppressive signals to disseminate. While often considered 'stop' signals for adherent cells, CXCR3-binding chemokines have recently been correlated positively with cancer progression though the molecular basis remains unclear.

RESULTS

Here, we examined the expression and function of two CXCR3 variants in human prostate cancer biopsies and cell lines. Globally, both CXCR3 mRNA and protein were elevated in localized and metastatic human cancer biopsies compared to normal. Additionally, CXCR3A mRNA level was upregulated while CXCR3B mRNA was downregulated in these prostate cancer specimens. In contrast to normal prostate epithelial cells (RWPE-1), CXCR3A was up to half the receptor in the invasive and metastatic DU-145 and PC-3 prostate cancer cells, but not in the localized LNCaP cells. Instead of inhibiting cell migration as in RWPE-1 cells, the CXCR3 ligands CXCL4/PF4 and CXCL10/IP10 promoted cell motility and invasiveness in both DU-145 and PC-3 cells via PLCβ3 and μ-calpain activation. CXCR3-mediated diminution of cell motility in RWPE-1 cells is likely a result of cAMP upregulation and m-calpain inhibition via CXCR3B signal transduction. Interestingly, overexpression of CXCR3B in DU-145 cells decreased cell movement and invasion.

CONCLUSION

These data suggest that the aberrant expression of CXCR3A and down-regulation of CXCR3B may switch a progression "stop" to a "go" signal to promote prostate tumor metastasis via stimulating cell migration and invasion.

Epithelial and mesenchymal phenotypic switchings modulate cell motility in metastasis

The most ominous stage of cancer progression is metastasis, or the dissemination of carcinoma cells from the primary site into distant organs. Metastases are often resistant to current extirpative therapies and even the newest biological agents cure only a small subset of patients. Therefore a greater understanding of tumor biology that integrates properties intrinsic to carcinomas with tissue environmental modulators of behavior is needed. In no aspect of tumor progression is this more evident than the acquisition of cell motility that is critical for both escape from the primary tumor and colonization. In this overview, we discuss how this behavior is modified by carcinoma cell phenotypic plasticity that is evidenced by reversible switching between epithelial and mesenchymal phenotypes. The presence or absence of intercellular adhesions mediate these switches and dictate the receptivity towards signals from the extracellular milieu. These signals, which include soluble growth factors, cytokines, and extracellular matrix embedded with matrikines and matricryptines will be discussed in depth. Finally, we will describe a new mode of discerning the balance between epithelioid and mesenchymal movement.