Current Cancer Drug Targets - Volume 23, Issue 1, 2023

Since their discovery, saikosaponins (SSs) have been found to play an important role in treating a variety of cancers via diverse mechanisms of action. This review summarizes the current research status and prospects of the anti-cancer activities of SSs, providing novel insights into the limitations of current studies. In addition, it discusses whether SSs can be applied in immunotherapy and the possible mechanisms by which SSs may facilitate immunotherapy. The research is significant to understanding the anti-cancer potents of SSs in the development of SSs-based therapeutic strategies and clinical practice.

The transforming growth factor-beta (TGF-β) signaling pathway has been reported to be dysregulated in the pathogenesis of several malignancies, including gynecologic cancers. This provides proof of concept of its potential value as a therapeutic target and prognostic biomarker in cervical cancer. Here we provide an overview of the biological role and clinical impact of TGF-β inhibitors either as a single agent or as a combinatorial therapy in gynecological cancers, concentrating on phase I to phase II/III clinical trials. Aberrant TGF-β signaling may lead to carcinogenesis. Inhibition of TGF-β represents an interesting area of focus for the treatment of gynecological cancer. Several TGF-β inhibitors are potential anticancer agents and are undergoing clinical trials in cancer, including galunisertib, dalantercept, and vigil. There is a growing body of data showing the potential therapeutic impact of targeting the TGF-β pathway in different cancer types, although further studies are still warranted to explore the value of this strategy and finding the most appropriate patients who could most benefit from therapy.

Aminopeptidases, which catalyze the cleavage of amino acids from the amino terminus of proteins, are widely distributed in the natural world and play a crucial role in cellular processes and functions, including metabolism, signaling, angiogenesis, and immunology. They are also involved in the homeostasis of amino acids and proteins that are required for cellular proliferation. Tumor cells are highly dependent on the exogenous supply of amino acids for their survival, and overexpression of aminopeptidase facilitates rapid tumor cell proliferation. In addition, clinical studies have demonstrated that patients with cancers with high aminopeptidase expression often have poorer outcomes. Emerging evidence supports the rationale of inhibiting aminopeptidase activity as a targeted approach for novel treatment options, as limiting the availability of amino acids can be selectively lethal to tumor cells. While there are agents that directly target aminopeptidases that demonstrate potential as cancer therapies, such as bestatin and tosedostat, more selective and more targeted therapeutic approaches are needed. This article specifically looks at the biological role of aminopeptidases in both normal and cancer processes, and their potential as a biological target for future therapeutic strategies. When examining previous publications, most do not cover aminopeptidases and their role in cancer processes. Aminopeptidases play a vital role in cell processes and functions; however, their overexpression may lead to a rapid proliferation of tumor cells. Emerging evidence supports the rationale of leveraging aminopeptidase activity as a targeted approach for new oncological treatments. This article specifically looks at the biological role of aminopeptidases in both normal and cancer processes, and their potential as a biological target for future therapeutic strategies.

Histone deacetylases (HDACs) are essential for maintaining homeostasis by catalyzing histone deacetylation. Aberrant expression of HDACs is associated with various human diseases. Although HDAC inhibitors are used as effective chemotherapeutic agents in clinical practice, their applications remain limited due to associated side effects induced by weak isoform selectivity. HDAC1 displays unique structure and cellular localization as well as diverse substrates and exhibits a wider range of biological functions than other isoforms. HDAC1 displays a unique structure primarily found in the nucleus and involved in epigenetic and transcriptional regulation. HDAC1 is ubiquitously expressed and associated with Sin3, NuRD, and CoRest transcription repressive complexes responsible for distinct cellular processes like cell proliferation and survival. HDAC1 inhibitors have been effectively used to treat various cancers such as gastric, breast, colorectal, prostate, colon, lung, ovarian, pancreatic, and inflammation without exerting significant toxic effects. In this review, we summarize four major structural classes of HDAC1 inhibitors (i.e., hydroxamic acid derivatives, benzamides, hydrazides, and thiols) with their structural activity relationship. This review is a comprehensive work on HDAC1 inhibitors to achieve deep insight of knowledge about the structural information of HDAC1 inhibitors. It may provide up-to-date direction for developing new selective HDAC1 inhibitors as anticancer agents.

Objective: Identification and validation of genes that functionally account for the growth and metastasis of prostate cancer. Methods: DU145-KO cell line was constructed by transfecting DU145 cells with lentivirus packaged with the genome-wide knock-out library. The DU145-KO cells were transplanted into the armpits of immunocompromised Nu/Nu mice, followed by the tissue collection from the lung at week 3 (early lung tissue) or week 7 (late lung tissue with micro-metastasis), as well as from primary tumor site at week 7 (late primary tumor) after inoculation. Lung metastasis was retrieved at various time points for DNA sequencing analysis to identify enriched sgRNAs, thus candidate genes/miRNAs. Further bioinformatics analysis and limited functional validation studies were carried out. Results: DU145-KO cells promoted the formation of transplanted tumors in mice and promoted the growth and metastasis of primary tumors, compared to the controls (DU145-NC cells). The analysis of sequence data showed that the abundance of sgRNAs significantly changed in the primary tumor and micro-metastasis site. Fifteen target genes (C1QTNF9B, FAM229A, hsa-mir-3929, KRT23, TARS2, CRADD, GRIK4, PLA2G15, LOXL1, SLITRK6, CDC42EP5, SLC2A4, PTGDS, MYL9 and ACOX2 for the enriched sgRNAs) have been selected for experimental validation, which showed that knock-out of any of these genes led to the enhanced potential of invasion and metastasis of DU145 cells. Conclusion: Genome-wide CRISPR-Cas9 knock-out screening technology combined with highthroughput sequencing analysis identified genes that potentially relate to prostate tumor invasion and metastasis. Analysis of these genes provided insights into biological pathways relevant to the disease and disclosed innovative markers for diagnosis or prognosis as well as potential targets for therapy.