Anastasis: cell recovery mechanisms and potential role in cancer

Targeting apoptosis in clear cell renal cell carcinoma

Clear cell renal cell carcinoma (ccRCC) is the most prevalent subtype of renal cancer, accounting for approximately 80% of all renal cell cancers. Due to its exceptional inter- and intratumor heterogeneity, it is highly resistant to conventional systemic therapies. Targeting the evasion of cell death, one of cancer's hallmarks, is currently emerging as an alternative strategy for ccRCC. In this article, we review the current state of apoptosis-inducing therapies against ccRCC, including antisense oligonucleotides, BH3 mimetics, histone deacetylase inhibitors, cyclin-kinase inhibitors, inhibitors of apoptosis protein antagonists, and monoclonal antibodies. Although preclinical studies have shown encouraging results, these compounds fail to improve patients' outcomes significantly. Current evidence suggests that inducing apoptosis in ccRCC may promote tumor progression through apoptosis-induced proliferation, anastasis, and apoptosis-induced nuclear expulsion. Therefore, re-evaluating this approach is expected to enable successful preclinical-to-clinical translation.

Cell Death, by Any Other Name…

Studies trying to understand cell death, this ultimate biological process, can be traced back to a century ago. Yet, unlike many other fashionable research interests, research on cell death is more alive than ever. New modes of cell death are discovered in specific contexts, as are new molecular pathways. But what is "cell death", really? This question has not found a definitive answer yet. Nevertheless, part of the answer is irreversibility, whereby cells can no longer recover from stress or injury. Here, we identify the most distinctive features of different modes of cell death, focusing on the executive final stages. In addition to the final stages, these modes can differ in their triggering stimulus, thus referring to the initial stages. Within this framework, we use a few illustrative examples to examine how intercellular communication factors in the demise of cells. First, we discuss the interplay between cell-cell communication and cell death during a few steps in the early development of multicellular organisms. Next, we will discuss this interplay in a fully developed and functional tissue, the gut, which is among the most rapidly renewing tissues in the body and, therefore, makes extensive use of cell death. Furthermore, we will discuss how the balance between cell death and communication is modified during a pathological condition, i.e., colon tumorigenesis, and how it could shed light on resistance to cancer therapy. Finally, we briefly review data on the role of cell-cell communication modes in the propagation of cell death signals and how this has been considered as a potential therapeutic approach. Far from vainly trying to provide a comprehensive review, we launch an invitation to ponder over the significance of cell death diversity and how it provides multiple opportunities for the contribution of various modes of intercellular communication.

Potential impacts of bisphenols on prostate cells: An overview of cytotoxicity, proliferation, oxidative stress, apoptosis, and ER-stress response activation

This study aimed to evaluate the toxic effects of Bisphenol A (BPA), Bisphenol F (BPF) and Bisphenol S (BPS) on PNT1A and PC-3 cells, focusing on their effects on endoplasmic reticulum (ER) stress and related pathways. PNT1A and PC-3 were treated with BPA, BPF and BPS at concentrations of 0.1, 1 and 10 μM for 48 h cytotoxicity, BrdU cell proliferation, ROS generation, apoptosis detection, gene expression analysis and Western blot analysis were performed. BPA induced proliferation and late apoptosis in PNT1A cells, whereas it induced both late apoptosis and early apoptosis in PC-3 cells. BPF and BPS induced late apoptosis in PC-3 cells. Increased ROS levels were observed in PNT1A cells exposed to 1-10 μM BPA. BPA, BPF and BPS increased the expression levels of ER stress-related genes in PNT1A cells. Furthermore, exposure to BPA increased the expression of ER stress-related CHOP/DDIT3 protein in PNT1A cells. These findings highlight the potential health risks associated with BPA, BPF and BPS exposure and emphasize the importance of investigating the underlying mechanisms by which these chemicals may affect human health. Further research is required to comprehensively understand the role of ER stress pathways in cellular responses to these substances.

Optimal blue light irradiation conditions for the treatment of acne vulgaris in a mouse model

BACKGROUND

Although blue light is one of the therapeutic approaches used to treat acne vulgaris (AV), there is no consensus on its effectiveness. As a result, it is not recommended in the major acne vulgaris treatment guidelines.

OBJECTIVE

The goal of this study was to look into the mechanism, safety, and efficacy of blue light therapy. We achieved this by examining the pathological response, inflammation, and depth of light penetration in a mouse model of cystic AV.

METHODS

The aims of the study were addressed by exposing the mice to light with a wavelength of 415 nm under four different irradiation conditions. The exposure was done for five consecutive days followed by a no irradiation period of 72 h.

RESULTS

Blue light treatment was most effective when irradiation was performed at 100 mW/cm² for 20 min for five consecutive days. Inflammatory responses emerged 72 h after the final irradiation dose was administered. These responses were not associated with apoptosis as cleaved caspase-3 staining revealed no significant increases in apoptosis in the skin under any of the tested conditions. Blue light reached the superficial layer of the acne cyst at 5% of the total irradiation power and was attenuated by half for every 50 μm of progress through the cyst.

CONCLUSION

In conclusion, blue light could control severe dermatologic inflammatory responses; therefore, it can be used to irradiate AV with high inflammation levels on a daily basis until improvement is observed. In addition, porphyrin, a metabolite of Cutibacterium acnes, and reactive oxygen species generated by the surrounding skin tissue may have essential roles in AV treatment.

What Are the Reasons for Continuing Failures in Cancer Therapy? Are Misleading/Inappropriate Preclinical Assays to Be Blamed? Might Some Modern Therapies Cause More Harm than Benefit?

Over 50 years of cancer research has resulted in the generation of massive amounts of information, but relatively little progress has been made in the treatment of patients with solid tumors, except for extending their survival for a few months at best. Here, we will briefly discuss some of the reasons for this failure, focusing on the limitations and sometimes misunderstanding of the clinical relevance of preclinical assays that are widely used to identify novel anticancer drugs and treatment strategies (e.g., "synthetic lethality"). These include colony formation, apoptosis (e.g., caspase-3 activation), immunoblotting, and high-content multiwell plate cell-based assays, as well as tumor growth studies in animal models. A major limitation is that such assays are rarely designed to recapitulate the tumor repopulating properties associated with therapy-induced cancer cell dormancy (durable proliferation arrest) reflecting, for example, premature senescence, polyploidy and/or multinucleation. Furthermore, pro-survival properties of apoptotic cancer cells through phoenix rising, failed apoptosis, and/or anastasis (return from the brink of death), as well as cancer immunoediting and the impact of therapeutic agents on interactions between cancer and immune cells are often overlooked in preclinical studies. A brief review of the history of cancer research makes one wonder if modern strategies for treating patients with solid tumors may sometimes cause more harm than benefit.