Peloruside A-Induced Cell Death in Hypoxia Is p53 Dependent in HCT116 Colorectal Cancer Cells

Application of three-dimensional cell culture technology in screening anticancer drugs

The drug development process involves a variety of drug activity evaluations, which can determine drug efficacy, strictly analyze the biological indicators after the drug action, and use these indicators as the preclinical drug evaluation criteria. At present, most of the screening of preclinical anticancer drugs mainly relies on traditional 2D cell culture. However, this traditional technology cannot simulate the tumor microenvironment in vivo, let alone reflect the characteristics of solid tumors in vivo, and has a relatively poor ability to predict drug activity. 3D cell culture is a technology between 2D cell culture and animal experiments, which can better reflect the biological state in vivo and reduce the consumption of animal experiments. 3D cell culture can link the individual study of cells with the study of the whole organism, reproduce in vitro the biological phenotype of cells in vivo more greatly, and thus predict the activity and resistance of anti-tumor drugs more accurately. In this paper, the common techniques of 3D cell culture are discussed, with emphasis on its main advantages and application in the evaluation of anti-tumor resistance, which can provide strategies for the screening of anti-tumor drugs.

Colorectal liver metastasis: molecular mechanism and interventional therapy

Colorectal cancer (CRC) is one of the most frequently occurring malignancy tumors with a high morbidity additionally, CRC patients may develop liver metastasis, which is the major cause of death. Despite significant advances in diagnostic and therapeutic techniques, the survival rate of colorectal liver metastasis (CRLM) patients remains very low. CRLM, as a complex cascade reaction process involving multiple factors and procedures, has complex and diverse molecular mechanisms. In this review, we summarize the mechanisms/pathophysiology, diagnosis, treatment of CRLM. We also focus on an overview of the recent advances in understanding the molecular basis of CRLM with a special emphasis on tumor microenvironment and promise of newer targeted therapies for CRLM, further improving the prognosis of CRLM patients.

Sulfonamido carboranes as highly selective inhibitors of cancer-specific carbonic anhydrase IX

Carbonic anhydrase IX (CA IX) is a transmembrane enzyme overexpressed in hypoxic tumors, where it plays an important role in tumor progression. Specific CA IX inhibitors potentially could serve as anti-cancer drugs. We designed a series of sulfonamide inhibitors containing carborane clusters based on prior structural knowledge of carborane binding into the enzyme active site. Two types of carborane clusters, 12-vertex dicarba-closo-dodecaborane and 11-vertex 7,8-dicarba-nido-undecaborate (dicarbollide), were connected to a sulfonamide moiety via aliphatic linkers of varying lengths (1-4 carbon atoms; n = 1-4). In vitro testing of CA inhibitory potencies revealed that the optimal linker length for selective inhibition of CA IX was n = 3. A 1-sulfamidopropyl-1,2-dicarba-closo-dodecaborane (3) emerged as the strongest CA IX inhibitor from this series, with a K_i value of 0.5 nM and roughly 1230-fold selectivity towards CA IX over CA II. X-ray studies of 3 yielded structural insights into their binding modes within the CA IX active site. Compound 3 exhibited moderate cytotoxicity against cancer cell lines and primary cell lines in 2D cultures. Cytotoxicity towards multicellular spheroids was also observed. Moreover, 3 significantly lowered the amount of CA IX on the cell surface both in 2D cultures and spheroids and facilitated penetration of doxorubicin. Although 3 had only a moderate effect on tumor size in mice, we observed favorable ADME properties and pharmacokinetics in mice, and preferential presence in brain over serum.

Neuroprotective Approach of Anti-Cancer Microtubule Stabilizers Against Tauopathy Associated Dementia: Current Status of Clinical and Preclinical Findings

Neuronal microtubule (MT) tau protein provides cytoskeleton to neuronal cells and plays a vital role including maintenance of cell shape, intracellular transport, and cell division. Tau hyperphosphorylation mediates MT destabilization resulting in axonopathy and neurotransmitter deficit, and ultimately causing Alzheimer’s disease (AD), a dementing disorder affecting vast geriatric populations worldwide, characterized by the existence of extracellular amyloid plaques and intracellular neurofibrillary tangles in a hyperphosphorylated state. Pre-clinically, streptozotocin stereotaxically mimics the behavioral and biochemical alterations similar to AD associated with tau pathology resulting in MT assembly defects, which proceed neuropathological cascades. Accessible interventions like cholinesterase inhibitors and NMDA antagonist clinically provides only symptomatic relief. Involvement of microtubule stabilizers (MTS) prevents tauopathy particularly by targeting MT oriented cytoskeleton and promotes polymerization of tubulin protein. Multiple in vitro and in vivo research studies have shown that MTS can hold substantial potential for the treatment of AD-related tauopathy dementias through restoration of tau function and axonal transport. Moreover, anti-cancer taxane derivatives and epothiolones may have potential to ameliorate MT destabilization and prevent the neuronal structural and functional alterations associated with tauopathies. Therefore, this current review strictly focuses on exploration of various clinical and pre-clinical features available for AD to understand the neuropathological mechanisms as well as introduce pharmacological interventions associated with MT stabilization. MTS from diverse natural sources continue to be of value in the treatment of cancer, suggesting that these agents have potential to be of interest in the treatment of AD-related tauopathy dementia in the future.

Interferon-stimulated gene 15 enters posttranslational modifications of p53

The tumor suppressor protein p53 is a central governor of various cellular signals. It is well accepted that ubiquitination as well as ubiquitin-like (UBL) modifications of p53 protein is critical in the control of its activity. Interferon-stimulated gene 15 (ISG15) is a well-known UBL protein with pleiotropic functions, serving both as a free intracellular molecule and as a modifier by conjugating to target proteins. Initially, attentions have historically focused on the antiviral effects of ISG15 pathway. Remarkably, a significant role in the processes of autophagy, DNA repair, and protein translation provided considerable insight into the new functions of ISG15 pathway. Despite the deterministic revelation of the relation between ISG15 and p53, the functional consequence of p53 ISGylation appears somewhat confused. More important, more recent studies have hinted p53 ubiquitination or other UBL modifications that might interconnect with its ISGylation. Here, we aim to summarize the current knowledge of p53 ISGylation and the differences in other significant modifications, which would be beneficial for the development of p53-based cancer therapy.