ABCG2 Gene and ABCG2 Protein Expression in Colorectal Cancer-In Silico and Wet Analysis

SNP's use as a potential chemotoxicity stratification tool in breast cancer: from bench to clinic

Breast cancer (BC) remains one of the most prevalent malignancies affecting women worldwide, necessitating ongoing research to improve treatment outcomes and minimize adverse effects associated with chemotherapy. This article explores the role of genetic variations, particularly single nucleotide polymorphisms (SNPs), in influencing the efficacy and toxicity of chemotherapeutic agents used in BC treatment. It highlights the impact of polymorphisms in drug metabolism and transport genes, such as UDP-glucuronosyltransferase 1A1 (UGT1A1), carbonyl reductase 1 (CBR1), and ATP-binding cassette multidrug transporter (ABCB1) on the risk of adverse effects, including cardiotoxicity and hematological toxicities. By identifying specific SNPs associated with drug response and toxicity, this research underscores the potential for personalized medicine approaches to optimize treatment regimens, enhance therapeutic efficacy, and minimize side effects in BC patients. The findings advocate for the integration of genetic screening in clinical practice to improve patient outcomes and tailor chemotherapy based on individual genetic profiles.

ARID3A inhibits colorectal cancer cell stemness and drug-resistance by targeting a multitude of stemness-associated genes

AIMS

ARID3A is highly expressed in CRC patients. However, the functional role of ARID3A in CRC remains unexplored. We sought to demonstrate ARID3A function in CRC.

MATERIALS AND METHODS

ARID3A was knocked-down using lentiviruses harboring shRNA. CRC patients' tissue cDNA array was used to assess expression of ARID3A. Effect of ARID3A on CSC-associated genes was analysed using real-time PCR array. Western-blot analysis and ChIP assay were used to validate the role of ARID3A. Paclitaxel-resistant CSC-enriched cell population was used to assess correlation between ARID3A, stemness and drug resistance potential. Ex vivo findings were corroborated on preclinical mouse model.

KEY FINDINGS

ARID3A expression was significantly higher throughout CRC stages than normal individuals. ARID3A expression was significantly higher in the aggressive CRC cell line HCT116 compared to HT29, which expressed higher levels of CD44, CD133, and EpCAM, suggesting a reciprocal relationship between ARID3A expression and CRC stemness. Real-time PCR-based stem cell array using ARID3A-knockdown HCT116 cells showed upregulation of 9 cancer stem cell (CSC)-associated genes. ChIP-assay verified binding of ARID3A on transcriptionally active promoter regions of CSC associated genes. ARID3A depletion led to enhanced proliferation, anchorage-independent growth, and ABCG2 upregulation in HCT116 cells. In paclitaxel-resistant HCT116 cells, ARID3A expression was dampened, whereas, CD44 and CD133 increased. ARID3A knockdown accelerated tumor growth and promoted larger tumor formation in nude-mouse xenograft model. Ki67, CD44 and CD133 were highly upregulated in knockdown tumors.

SIGNIFICANCE

This study demonstrated that ARID3A inhibits CRC stemness, anchorage-independent growth, self-renewal, anti-cancer drug resistance of CRC cells and tumor growth in vivo.

The role of ABCG2 in health and disease: Linking cancer therapy resistance and other disorders

All biological systems have adenosine triphosphate (ATP) binding cassette (ABC) transporters, one of the significant protein superfamilies involved in transport across membranes. ABC transporters have been implicated in the etiology of diseases like metabolic disorders, cancer, and Alzheimer's disease. ATP-binding cassette superfamily G member 2 (ABCG2), one of the ABC transporters, is necessary for the ATP-dependent efflux of several endogenous and exogenous substances. Consequently, it maintained cellular homeostasis and shielded tissue from xenobiotic substances. ABCG2 was initially identified in an Adriamycin-selected breast cancer cell line (MCF-7/AdrVp) and was linked to the emergence of multidrug resistance (MDR) in cancerous cells. Under many pathophysiological conditions, including inflammation, disease pathology, tissue injury, infection, and in response to xenobiotics and endogenous substances, the expression of ABCG2 undergoes alterations that result in modifications in its function and activity. Genetic variants in the ABCG2 transporter can potentially impact its expression and function, contributing to the development of many disorders. This review aimed to illustrate the impact of ABCG2 expression and its variants on oral drug bioavailability, MDR in specific cancer cells, explore the relationship between ABCG2 expression and other disorders such as gout, Alzheimer's disease, epilepsy, and erythropoietic protoporphyria, and demonstrate the influence of various synthetic and natural compounds in regulating ABCG2 expression.

SLC38A3 Promotes the Proliferation and Migration of Tumor Cells and Predicts Poor Prognosis in Colorectal Cancer

Previous studies have revealed that abnormal expressions of membrane transporters were associated with colorectal cancer (CRC). We herein performed a comprehensive bioinformatics analysis to identify the key transporter protein-related genes involved in CRC and potential mechanisms. Differentially expressed transporter protein-related genes (DE-TPRGs) were identified from CRC and normal samples using The Cancer Genome Atlas database. SLC38A3 expression was validated by immunohistochemistry and RT-qPCR, and the potential mechanism was explored. A total of 63 DE-TPRGs (29 up-regulated and 34 down-regulated) were screened. Inside, ABCC2, ABCG2, SLC4A4, SLC9A3, SLC15A1, and SLC38A3 were identified as hub genes. SLC38A3 is indeed upregulated in colorectal cancer patients. Furthermore, we found that knockdown of SLC38A3 inhibited the proliferation and migration of HCT116 cells, and Hsp70 ATPase activator could rescue it. Overall, SLC38A3 is a novel potential biomarker involved in CRC progression and promotes the proliferation and migration of tumor cells by positively regulating the function of Hsp70.

Novel Therapeutic Approaches for Colorectal Cancer Treatment

According to GLOBOCAN 2020 data, colorectal cancer (CRC) represents the third most common malignancy and the second most deadly cancer worldwide [...].

The Non-Invasive Prediction of Colorectal Neoplasia (NIPCON) Study 1995-2022: A Comparison of Guaiac-Based Fecal Occult Blood Test (FOBT) and an Anti-Adenoma Antibody, Adnab-9

Given the need to improve the sensitivity of non-invasive methods to detect colorectal neoplasia, particularly adenomas, we compared a fecal test using a monoclonal antibody (Mab) raised against constituents of colonic adenomas designated Adnab-9 (Adenoma Antibody 9), recognizing an N-linked 87 kDa glycoprotein, to gFOBT, which is shown to reduce CRC mortality. p87 immunohistochemistry testing is significantly more sensitive (OR 3.64[CI 2.37-5.58]) than gFOBT (guaiac-based fecal occult blood test) for adenomas (<3 in number), advanced adenomas (OR 4.21[CI 2.47-7.15]), or a combination of the two (OR 3.35[CI 2.47-4.53]). p87 immunohistochemistry shows regional Paneth cell (PC) expression mainly in the right-sided colon and is significantly reduced in the ceca of African Americans (p < 0.0001). In a subset of patients, we obtained other body fluids such as urine, colonic effluent, and saliva. Urine tests (organ-specific neoantigen) showed a significant difference for advanced adenomas (p < 0.047). We conclude that fecal p87 testing is more sensitive than gFOBT and Adnab-9 and could be used to better direct the colonoscopy screening effort.