Enhanced anti-tumor efficacy of aspirin combined with triptolide in cervical cancer cells

Potential antitumor activity of triptolide and its derivatives: Focused on gynecological and breast cancers

Cancer remains one of the greatest global health concerns. This is especially true for gynecological cancers, which include cervical, ovarian, and endometrial cancers, and breast cancer. Natural products used for cancer treatment offer some unique advantages. Triptolide (TPL) is a biologically active terpenoid extracted from Tripterygium wilfordii, which exhibits anti-inflammatory, immunosuppressive, antitumor, and other pharmacological activities. However, clinical applications of TPL are restricted because of poor water solubility and severe cytotoxicity; to overcome these limitations, various TPL derivatives and drug delivery systems, especially nanocarriers, have been used. Furthermore, various preclinical and clinical studies have demonstrated that TPL and its derivatives exhibit excellent antitumor effects by targeting proteins involved in multiple signaling pathways. Here, we review the progress regarding novel drug delivery systems, antitumor activities, and molecular mechanisms of action of TPL and its derivatives against gynecological and breast cancers. TPL and its derivatives inhibit tumor growth, suppress tumor metastasis, and enhance the drug sensitization of resistant cancers. In addition, TPL and its derivatives exert synergistic antitumor effects against gynecological and breast cancers when combined with existing antitumor drugs, such as carboplatin, cisplatin, and PI3K inhibitors. Moreover, we highlight the clinical potential of TPL analogs against cancer from bench to bedside and their prospects for future applications in gynecologic and breast cancers.

Cervical cancer subtypes harbouring integrated and/or episomal HPV16 portray distinct molecular phenotypes based on transcriptome profiling of mRNAs and miRNAs

Heterogeneity in cervical cancers (CaCx) in terms of HPV16 physical status prompted us to investigate the mRNA and miRNA signatures among the different categories of CaCx samples. We performed microarray-based mRNA expression profiling and quantitative real-time PCR-based expression analysis of some prioritised miRNAs implicated in cancer-related pathways among various categories of cervical samples. Such samples included HPV16-positive CaCx cases that harboured either purely integrated HPV16 genomes (integrated) and those that harboured episomal viral genomes, either pure or concomitant with integrated viral genomes (episomal), which were compared with normal cervical samples that were either HPV negative or positive for HPV16. The mRNA expression profile differed characteristically between integrated and episomal CaCx cases for enriched biological pathways. miRNA expression profiles also differed among CaCx cases compared with controls (upregulation—miR-21, miR-16, miR-205, miR-323; downregulation—miR-143, miR-196b, miR-203, miR-34a; progressive upregulation—miR-21 and progressive downregulation—miR-143, miR-34a, miR-196b and miR-203) in the order of HPV-negative controls, HPV16-positive non-malignant samples and HPV16-positive CaCx cases. miR-200a was upregulated in HPV16-positive cervical tissues irrespective of histopathological status. Expression of majority of the predicted target genes was negatively correlated with their corresponding miRNAs, irrespective of the CaCx subtypes. E7 mRNA expression correlated positively with miR-323 expression among episomal cases and miR-203, among integrated cases. miR-181c expression was downregulated only among the episomal CaCx cases and negatively correlated with protein coding transcript of the proliferative target gene, CKS1B of the significantly enriched “G2/M DNA Damage Checkpoint Regulation” pathway among CaCx cases. Thus, the two CaCx subtypes are distinct entities at the molecular level, which could be differentially targeted for therapy. In fact, availability of a small molecule inhibitor of CKS1B, suggests that drugging CKS1B could be a potential avenue of treating the large majority of CaCx cases harbouring episomal HPV16.

Consensus reference gene(s) for gene expression studies in human cancers: end of the tunnel visible?

BACKGROUND

Gene expression studies are increasingly used to provide valuable information on the diagnosis and prognosis of human cancers. Also, for in vitro and in vivo experimental cancer models gene expression studies are widely used. The complex algorithms of differential gene expression analyses require normalization of data against a reference or normalizer gene, or a set of such genes. For this purpose, mostly invariant housekeeping genes are used. Unfortunately, however, there are no consensus (housekeeping) genes that serve as reference or normalizer for different human cancers. In fact, scientists have employed a wide range of reference genes across different types of cancer for normalization of gene expression data. As a consequence, comparisons of these data and/or data harmonizations are difficult to perform and challenging. In addition, an inadequate choice for a reference gene may obscure genuine changes and/or result in erroneous gene expression data comparisons.

METHODS

In our effort to highlight the importance of selecting the most appropriate reference gene(s), we have screened the literature for gene expression studies published since the turn of the century on thirteen of the most prevalent human cancers worldwide.

CONCLUSIONS

Based on the analysis of the data at hand, we firstly recommend that in each study the suitability of candidate reference gene(s) should carefully be evaluated in order to yield reliable differential gene expression data. Secondly, we recommend that a combination of PPIA and either GAPDH, ACTB, HPRT and TBP, or appropriate combinations of two or three of these genes, should be employed in future studies, to ensure that results from different studies on different human cancers can be harmonized. This approach will ultimately increase the depth of our understanding of gene expression signatures across human cancers.

Targets and molecular mechanisms of triptolide in cancer therapy

Triptolide (TPL/TL) is a natural drug with novel anticancer effects. Preclinical studies indicated that TPL inhibits cell proliferation, induces cell apoptosis, inhibits tumor metastasis and enhances the effect of other therapeutic methods in various cancer cell lines. Multiple molecules and signaling pathways, such as caspases, heat-shock proteins, NF-κB, and deoxyribonucleic acid (DNA) repair-associated factors, are associated with the anti-cancer effect. TPL also improves chemoradiosensitivity in cancer therapy. Phase I trials indicate the potential clinical value of TPL use. However, further trials with larger sample sizes are needed to confirm these results.

Selective killing effect of oxytetracycline, propafenone and metamizole on A549 or Hela cells

OBJECTIVE

To determine the selective killing effect of oxytetracycline, propafenone and metamizole on A549 or Hela cells.

METHODS

Proliferation assay, lactate dehydrogenase (LDH) assay, apoptosis detecting, flow cytometry and western blot were performed.

RESULTS

It was found that treatment with propafenone at the concentration of 0.014 g/L or higher for 48 h could induce apoptosis in Hela cells greatly, while it was not observed in oxytetracycline and metamizole at the concentration of 0.20 g/L for 48 h. Oxytetracycline, propafenone and metamizole all displayed evident inhibitory effects on the proliferation of A549 cells. The results of LDH assay demonstrated that the drugs at the test range of concentration did not cause necrosis in the cells. Propafenone could elevate the protein level of P53 effectively (P<0.01).

CONCLUSIONS

Oxytetracycline, propafenone and metamizol (dipyrone) all displayed evident inhibitory effects on the proliferation of A549 cells. Propafenone also displayed evident inhibitory effects on the proliferation of Hela cells.