Imidazole Analogs of Vascular-Disrupting Combretastatin A-4 with Pleiotropic Efficacy against Resistant Colorectal Cancer Models

Bioinformatics analysis of colorectal cancer transcriptomic data reveals novel prognostic signature and potential biomarker genes

OBJECTIVE

Colorectal cancer (CRC) is a type of digestive system cancer. At the molecular level, some factors, including genetic and epigenetic factors, as well as various signaling pathways such as oxidative stress and inflammation, play an active role in the onset of CRC. Genetic and epigenetic mutations, particularly in oncogenes and tumor suppressor genes, occur during colorectal adenocarcinoma development as a result of a change in gastrointestinal epithelial cell proliferation and self-renewal rates. This study aimed to determine the genes and molecular mechanisms that play a role in the emergence of this disease by analyzing the CRC data.

MATERIAL AND METHODS

Microarray data selected for bioinformatics analysis is Gene Expression data stored with the code GSE110224 in the National Center for Biotechnology Information (NCBI) Gene Expression Omnibus (GEO) database. Gene expression analysis, functional clustering analysis, enrichment analysis, and pathway analysis were performed using this data set.

RESULTS

Analysis of raw transcriptomic data revealed 1770 common DEGs in CRC. While the expression level of 769 of these genes increased, the expression level of 1001 genes decreased. A Protein-protein interaction (PPI) network was created from the first 25 genes with increased expression levels and 11 signature genes were identified. Increased expression of REG1A, MMP3, FOXQ1 and CEMIP genes and decreased expression of AQP8, CA1, CLDN8, PYY, CA4, CEACAM7 and SLC30A10 genes were observed.

CONCLUSIONS

This approach revealed a CRC-specific molecular profile and may provide some guidance for further investigation of potential biomarkers for diagnosis and prognosis prediction of CRC patients.

Combretastatin A-4 based compounds as potential anticancer agents: A review

The current review discusses the importance of combretastatin A-4 (CA-4) as a lead compound of microtubule targeting agents. CA-4 holds a unique place among naturally occurring compounds having cytotoxic activity. In this review an overall picture of design strategies, structure-activity relationship, synthesis, cytotoxic activity, and binding interactions of promising CA-4 analogues, are discussed and arranged chronologically from 2016 to early 2023. Also, this review emphasizes their biological activity as anticancer agents, within an overview of clinical application limitation and suggested strategies to overcome. Dual targeting tubulin inhibitors showed highpotentialto surpass medication resistance and provide synergistic efficacy. Linking platinum (IV), amino acids, and HDAC targeting moieties to active tubulin inhibitorsproduced potent active compounds. Analogues of CA-4 bridged with azetidin-2-one, pyrazole, sulfide, or carrying selenium atom exhibited cytotoxic action against a variety of malignant cell lines through different pathways.

Luciferase Expressing Preclinical Model Systems Representing the Different Molecular Subtypes of Colorectal Cancer

Colorectal cancer (CRC) is a heterogeneous disease. More insight into the biological diversity of CRC is needed to improve therapeutic outcomes. Established CRC cell lines are frequently used and were shown to be representative models of the main subtypes of CRC at the genomic and transcriptomic level. In the present work, we established stable, luciferase expressing derivatives from 10 well-established CRC cell lines, generated spheroids and subcutaneous xenograft tumors in nude mice, and performed comparative characterization of these model systems. Transcriptomic analyses revealed the close relation of cell lines with their derived spheroids and xenograft tumors. The preclinical model systems clustered with patient tumor samples when compared to normal tissue thereby confirming that cell-line-based tumor models retain specific characteristics of primary tumors. Xenografts showed different differentiation patterns and bioluminescence imaging revealed metastatic spread to the lungs. In addition, the models were classified according to the CMS classification system, with further sub-classification according to the recently identified two intrinsic epithelial tumor cell states of CRC, iCMS2 and iCMS3. The combined data showed that regarding primary tumor characteristics, 3D-spheroid cultures resemble xenografts more closely than 2D-cultured cells do. Furthermore, we set up a bioluminescence-based spheroid cytotoxicity assay in order to be able to perform dose-response relationship studies in analogy to typical monolayer assays. Applying the established assay, we studied the efficacy of oxaliplatin. Seven of the ten used cell lines showed a significant reduction in the response to oxaliplatin in the 3D-spheroid model compared to the 2D-monolayer model. Therapy studies in selected xenograft models confirmed the response or lack of response to oxaliplatin treatment. Analyses of differentially expressed genes in these models identified CAV1 as a possible marker of oxaliplatin resistance. In conclusion, we established a combined 2D/3D, in vitro/in vivo model system representing the heterogeneity of CRC, which can be used in preclinical research applications.