C-X-C chemokine receptor type 5 gene polymorphism affects gene expression in CD4+ T cells and is associated with increased risk of colorectal cancer

CXC Chemokine Receptor Type 5 Gene Polymorphisms in a Cohort of Egyptian Patients with Diffuse Large B-Cell Lymphoma

BACKGROUND

The chemokine receptor CXCR5 is selectively expressed on B cells; it is involved in lymphocyte homing and the development of normal lymphoid tissue. Its principle ligand is CXCL13 or B lymphocyte chemoattractant. Three polymorphisms in the CXCR5 gene, rs148351692 C/G, rs6421571 C/T, and rs78440425 G/A, have been identified.

OBJECTIVE

To assess the genetic polymorphisms of CXCR5 and evaluate their possible contribution to the susceptibility and response to therapy of diffuse large B-cell lymphoma (DLBCL).

PATIENTS AND METHODS

Fifty DLBCL (not otherwise specified) patients and 50 control subjects were included in this study. CXCR5 genotypes were determined by PCR-RFLP.

RESULTS

Our study revealed that the CXCR5 rs148351692 C/G and rs6421571 C/T gene polymorphisms are associated with an increased risk of developing DLBCL (OR 28.57 [95% CI 8.96-96.56] and 3.45 [1.67-11.83] respectively), while CXCR5 rs78440425 G/A showed no association with the risk of lymphoma. Moreover, the double and triple combined gene polymorphisms are associated with an increased risk of developing DLBCL of approximately 120-fold and 105-fold, respectively. CXCR5 gene polymorphisms had no significant impact on disease outcome or response to therapy.

CONCLUSIONS

CXCR5 gene polymorphisms could be considered a potential risk factor for the development of DLBCL.

Molecular Targets in Precision Chemoprevention of Colorectal Cancer: An Update from Pre-Clinical to Clinical Trials

Colorectal cancer (CRC) is one of the leading causes of cancer deaths worldwide. The initiation and progression of CRC is a multi-step process that proceeds via precursor lesions to carcinoma, with each stage characterized by its distinct molecular and tissue microenvironment changes. Precursor lesions of CRC, aberrant crypt foci, and adenoma exhibit drastic changes in genetic, transcriptomic, and proteomic profiles compared to normal tissue. The identification of these changes is essential and provides further validation as an initiator or promoter of CRC and, more so, as lesion-specific druggable molecular targets for the precision chemoprevention of CRC. Mutated/dysregulated signaling (adenomatous polyposis coli, β-catenin, epidermal growth factor receptor, V-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog (KRAS), tumor protein53, Akt, etc.), inflammatory (cyclooxygenase-2, microsomal prostaglandin E synthase-1, inducible nitric oxide synthase, and other pro-inflammatory mediators), and metabolic/growth factor (fatty acid synthase, β-Hydroxy β-methylglutaryl-CoA reductase, and ornithine decarboxylase) related targets are some of the well-characterized molecular targets in the precision chemoprevention of CRC. In this review, we discuss precursor-lesion specific targets of CRC and the current status of pre-clinical studies regarding clinical interventions and combinations for better efficacy and safety toward future precision clinical chemoprevention. In addition, we provide a brief discussion on the usefulness of secondary precision chemopreventive targets for tertiary precision chemoprevention to improve the disease-free and overall survival of advanced stage CRC patients.

CXCL13/CXCR5 signaling axis in cancer

The tumor microenvironment comprises stromal and tumor cells which interact with each other through complex cross-talks that are mediated by a variety of growth factors, cytokines, and chemokines. The chemokine ligand 13 (CXCL13) and its chemokine receptor 5 (CXCR5) are among the key chemotactic factors which play crucial roles in deriving cancer cell biology. CXCL13/CXCR5 signaling axis makes pivotal contributions to the development and progression of several human cancers. In this review, we discuss how CXCL13/CXCR5 signaling modulates cancer cell ability to grow, proliferate, invade, and metastasize. Furthermore, we also discuss the preliminary evidence on context-dependent functioning of this axis within the tumor-immune microenvironment, thus, highlighting its potential dichotomy with respect to anticancer immunity and cancer immune-evasion mechanisms. At the end, we briefly shed light on the therapeutic potential or implications of targeting CXCL13/CXCR5 axis within the tumor microenvironment.