Low cleaved caspase-7 levels indicate unfavourable outcome across all breast cancers

Anastasis and Other Apoptosis-Related Prosurvival Pathways Call for a Paradigm Shift in Oncology: Significance of Deintensification in Treating Solid Tumors

What is apoptosis? The Nomenclature Committee on Cell Death and numerous other pioneering cancer/p53 biologists use the terms "apoptosis" and "cell death" interchangeably, disregard the mind-numbing complexity and heterogeneity that exists within a tumor (intratumor heterogeneity), disregard the contribution of polyploid giant cancer cells (PGCCs; the root causes of therapy resistance and relapse) to this heterogeneity, and then propose novel apoptosis-stimulating anticancer strategies. This is shocking for the following three reasons. First, clinical studies reported since the 1990s have revealed that increased apoptosis in solid tumors is associated with increased tumor diversity and poor prognosis. Second, we have known for years that dying (apoptotic) cancer cells release a panel of secretions (e.g., via phoenix rising and other pathways) that promote metastatic outgrowth. Third, over a decade ago, it was demonstrated that cancer cells can recover from late stages of apoptosis (after the formation of apoptotic bodies) via the homeostatic process of anastasis, resulting in the emergence of aggressive variants. The cell surface expression of CD24 has recently been reported to be preferentially enriched in recovered (anastatic) cancer cells that exhibit tumorigenic properties. These and related discoveries outlined herein call for a paradigm shift in oncology to focus on strategies that minimize the occurrence of treacherous apoptosis and other tumor-repopulating events (e.g., therapy-induced cancer cell dormancy and reactivation). They also raise an intriguing question: is deregulated anastasis (rather than evasion of apoptosis) a hallmark of cancer?

Leveraging the redundancy of S-denitrosylases in response to S-nitrosylation of caspases: Experimental strategies and beyond

Redox-based protein posttranslational modifications, such as S-nitrosylation of critical, active site cysteine thiols have garnered significant clinical attention and research interest, reasoning for one of the crucial biological implications of reactive messenger molecule, nitric oxide in the cellular repertoire. The stringency of the S-(de)nitrosylation-based redox switch governs the activity and contribution of several susceptible enzymes in signal transduction processes and diverse pathophysiological settings, thus establishing it as a transient yet reasonable, and regulated mechanism of NO adduction and release. Notably, endogenous proteases like cytosolic and mitochondrial caspases with a molecular weight ranging from 33 to 55 kDa are susceptible to performing this biochemistry in the presence of major oxidoreductases, which further unveils the enormous redox-mediated regulational control of caspases in the etiology of diseases. In addition to advancing the progress of the current state of understanding of 'redox biochemistry' in the field of medicine and enriching the existing dynamic S-nitrosoproteome, this review stands as a testament to an unprecedented shift in the underpinnings for redundancy and redox relay between the major redoxin/antioxidant systems, fine-tuning of which can command the apoptotic control of caspases at the face of nitro-oxidative stress. These intricate functional overlaps and cellular backups, supported rationally by kinetically favorable reaction mechanisms suggest the physiological relevance of identifying and involving such cognate substrates for cellular S-denitrosylases that can shed light on the bigger picture of extensively proposing targeted therapies and redox-based drug designing to potentially alleviate the side effects of NOx/ROS in disease pathogenesis.

Targeting NAD Metabolism: Rational Design, Synthesis and In Vitro Evaluation of NAMPT/PARP1 Dual-Target Inhibitors as Anti-Breast Cancer Agents

The malignancy of breast cancer poses a global challenge, with existing treatments often falling short of desired efficacy. Extensive research has underscored the effectiveness of targeting the metabolism of nicotinamide adenine dinucleotide (NAD), a pivotal molecule crucial for cancer cell survival and growth, as a promising anticancer strategy. Within mammalian cells, sustaining optimal NAD concentrations relies on two key enzymes, namely nicotinamide phosphoribosyltransferase (NAMPT) and poly(ADP-ribose) polymer 1 (PARP1). Recent studies have accentuated the potential benefits of combining NAMPT inhibitors and PARP1 inhibitors to enhance therapeutic outcomes, particularly in breast cancer. In this study, we designed and synthesized eleven novel NAMPT/PARP1 dual-target inhibitors. Among them, compound DDY02 exhibited acceptable inhibitory activities against both NAMPT and PARP1, with IC50 values of 0.01 and 0.05 µM, respectively. Moreover, in vitro evaluations revealed that treatment with DDY02 resulted in proliferation inhibition, NAD depletion, DNA damage, apoptosis, and migration inhibition in MDA-MB-468 cells. These results posit DDY02, by targeting NAD metabolism through inhibiting both NAMPT and PARP1, as a promising lead compound for the development of breast cancer therapy.

Changing the Landscape of Solid Tumor Therapy from Apoptosis-Promoting to Apoptosis-Inhibiting Strategies

The many limitations of implementing anticancer strategies under the term "precision oncology" have been extensively discussed. While some authors propose promising future directions, others are less optimistic and use phrases such as illusion, hype, and false hypotheses. The reality is revealed by practicing clinicians and cancer patients in various online publications, one of which has stated that "in the quest for the next cancer cure, few researchers bother to look back at the graveyard of failed medicines to figure out what went wrong". The message is clear: Novel therapeutic strategies with catchy names (e.g., synthetic "lethality") have not fulfilled their promises despite decades of extensive research and clinical trials. The main purpose of this review is to discuss key challenges in solid tumor therapy that surprisingly continue to be overlooked by the Nomenclature Committee on Cell Death (NCCD) and numerous other authors. These challenges include: The impact of chemotherapy-induced genome chaos (e.g., multinucleation) on resistance and relapse, oncogenic function of caspase 3, cancer cell anastasis (recovery from late stages of apoptosis), and pitfalls of ubiquitously used preclinical chemosensitivity assays (e.g., cell "viability" and tumor growth delay studies in live animals) that score such pro-survival responses as "lethal" events. The studies outlined herein underscore the need for new directions in the management of solid tumors.

Regulatory Role of Apoptotic and Inflammasome Related Proteins and Their Possible Functional Aspect in Thiram Associated Tibial Dyschondroplasia of Poultry

Tibial dyschondroplasia debilities apoptotic and inflammasomal conditions that can further destroy chondrocytes. Inflammasomes are specialized protein complexes that process pro-inflammatory cytokines, e.g., interleukin-1β (IL-1β) and IL-18. Moreover, there is mounting evidence that many of the signaling molecules that govern programmed cell death also affect inflammasome activation in a cell-intrinsic way. During the last decade, apoptotic functions have been described for signaling molecules involving inflammatory responses and cell death pathways. Considering these exceptional developments in the knowledge of processes, this review gives a glimpse of the significance of these two pathways and their connected proteins in tibial dyschondroplasia. The current review deeply elaborates on the elevated level of signaling mediators of mitochondrial-mediated apoptosis and the inflammasome. Although investigating these pathways’ mechanisms has made significant progress, this review identifies areas where more study is especially required. It might lead to developing innovative therapeutics for tibial dyschondroplasia and other associated bone disorders, e.g., osteoporosis and osteoarthritis, where apoptosis and inflammasome are the significant pathways.

Construction and validation of a prognostic risk model for breast cancer based on protein expression

Breast cancer (BRCA) is the primary cause of mortality among females globally. The combination of advanced genomic analysis with proteomics characterization to construct a protein prognostic model will help to screen effective biomarkers and find new therapeutic directions. This study obtained proteomics data from The Cancer Proteome Atlas (TCPA) dataset and clinical data from The Cancer Genome Atlas (TCGA) dataset. Kaplan–Meier and Cox regression analyses were used to construct a prognostic risk model, which was consisted of 6 proteins (CASPASE7CLEAVEDD198, NFKBP65-pS536, PCADHERIN, P27, X4EBP1-pT70, and EIF4G). Based on risk curves, survival curves, receiver operating characteristic curves, and independent prognostic analysis, the protein prognostic model could be viewed as an independent factor to accurately predict the survival time of BRCA patients. We further validated that this prognostic model had good predictive performance in the GSE88770 dataset. The expression of 6 proteins was significantly associated with the overall survival of BRCA patients. The 6 proteins and encoding genes were differentially expressed in normal and primary tumor tissues and in different BRCA stages. In addition, we verified the expression of 3 differential proteins by immunohistochemistry and found that CDH3 and EIF4G1 were significantly higher in breast cancer tissues. Functional enrichment analysis indicated that the 6 genes were mainly related to the HIF-1 signaling pathway and the PI3K-AKT signaling pathway. This study suggested that the prognosis-related proteins might serve as new biomarkers for BRCA diagnosis, and that the risk model could be used to predict the prognosis of BRCA patients.

BCL(X)L and BCL2 increase mitochondrial dynamics in breast cancer cell: Evidence from functional and genetic studies

BCL2 family proteins are important regulators of mitochondrial outer membrane permeabilization (MOMP). In recent years, BCL2 family proteins have also been linked to the regulation of mitochondrial bioenergetics and dynamics. Given their overexpression in breast cancer cells, we sought to explore whether two key members of this family, BCL2 and BCL(X)L impacted on mitochondrial fusion/fission processes. By employing a single cell imaging and RNA sequencing we found that overexpression of BCL2 or BCL(X)L increases mitochondrial dynamics and alters the expression profile of genes involved in this process. Collectively, our data show that overexpression of BCL2 proteins regulates mitochondrial dynamics in breast cancer tumor cells.

BCL(X)L and BCL2 increase the metabolic fitness of breast cancer cells: a single-cell imaging study

The BCL2 family of proteins regulate apoptosis by controlling mitochondrial outer membrane permeability. However, the effects on mitochondrial structure and bioenergetics have also been reported. Here we comprehensively characterized the effects of BCL2 and BCL(X)L on cellular energetics in MCF7 breast cancer cells using time-lapse confocal single-cell imaging and mitochondrial and cytosolic FRET reporters. We found that BCL2 and BCL(X)L increase the metabolic robustness of MCF7 cells, and that this was associated with increased mitochondrial NAD(P)H and ATP levels. Experiments with the F₁F₀ synthase inhibitor oligomycin demonstrated that BCL2 and in particular BCL(X)L, while not affecting ATP synthase activity, more efficiently coupled the mitochondrial proton motive force with ATP production. This metabolic advantage was associated with an increased resistance to nutrient deprivation and enhanced clonogenic survival in response to metabolic stress, in the absence of profound effects on cell death. Our data suggest that a primary function of BCL(X)L and BCL2 overexpression in tumor cells is to increase their resistance to metabolic stress in the tumor microenvironment, independent of cell death signaling.

Downregulation of Diacylglycerol kinase zeta (DGKZ) suppresses tumorigenesis and progression of cervical cancer by facilitating cell apoptosis and cell cycle arrest

Diacylglycerol kinase zeta (DGKZ) participates in cancer progression. Here, the current work aims to identify the functional role of DGKZ in cervical cancer (CC). DGKZ expression in cervical cancer tissues and paired adjacent normal cervical tissues was assessed using Immunohistochemistry assay. SiHa and HeLa cells were transfected with lentivirus plasmids (sh-DGKZ or sh-NC) to evaluate the effects of DGKZ knockdown on cell proliferation, apoptosis and cell cycle distribution in vitro. Furthermore, BALB/c nude mice were injected subcutaneously with Lentivirus-sh-DGKZ-SiHa cells or Lentivirus-sh-NC-SiHa cells to analyze the influence of DGKZ silencing on tumor growth of CC in vivo. Moreover, the potential molecular mechanisms were predicted by GO and KEGG analysis and preliminarily explored through PathScan Analysis. Elevated DGKZ expression in cervical tumor was observed. Downregulation of DGKZ repressed proliferation and boosted apoptosis of SiHa and HeLa cells and induced cell cycle arrest at G0/G1 phase. In addition, Knockdown of DGKZ restrained tumor growth in tumor xenograft mice. Importantly, GO and KEGG analysis displayed that differentially expressed proteins induced by silence of DGKZ were mostly enriched in autophagy or mitophagy, indicating that the functions of DGKZ on cell proliferation and tumor growth may be associated with autophagy or mitophagy. PathScan analysis presented that PI3K-AKT and TAK1-NF-κB signaling pathways were prominently inhibited in SiHa cells transfected with sh-DGKZ. In summary, downregulation of DGKZ impeded cell proliferation, boosted cell apoptosis and induced cell cycle arrest to suppress tumorigenesis and progression of cervical cancer.

Intrinsic and extrinsic pathways of apoptosis: Role in cancer development and prognosis

Apoptosis, also named programmed cell death, is a fundament process required for morphogenetic homeostasis during early development and in pathophysiological conditions. It is come into existence in 1972 by work of Kerr, Wyllie and Currie and later on investigated during the research on development of the C. elegans. Trigger by several stimuli, apoptosis is necessary during the embryonic development and aging as homeostatic mechanism to control the cell population and also play a key role as defense mechanism against the immune responses and elimination of damaged cells. Cancer, a genetic disease, is a growing burden on the health and economy of both developing and developed countries. Every year there is tremendously increasing in the number of new cancer cases and mortality rate. Although, there is a significant improvement have been made in biotechnological and bioinformatic fields however, the therapeutic advantages and cancer etiology is still under explored. Several studies determined the deregulation of different apoptotic components during the cancer development and progression. Apoptosis relies on activation of distinct signaling pathways that are often deregulated in cancer. Thus, exploring the single or more than one apoptotic component underlying their expression in carcinogenesis could help to track the disease progression. Current book chapter will provide the several evidences supporting the use of different apoptotic components as prognosis and prediction markers in various human cancer types.

SAHA and EGCG Promote Apoptosis in Triple-negative Breast Cancer Cells, Possibly Through the Modulation of cIAP2

BACKGROUND/AIM

Inhibition of apoptosis is one of the hallmarks of cancer, and anti-apoptotic genes are often targets of genetic and epigenetic alterations. Cellular inhibitor of apoptosis 2 (cIAP2) has a role in degrading caspases by linking them to ubiquitin molecules, and is upregulated in triple-negative breast cancer (TNBC). Previous studies have demonstrated that cIAP2 may play a role in the epithelial-to-mesenchymal transition (EMT).

MATERIALS AND METHODS

Suberoylanilide hydroxamic acid (SAHA), a histone deacetylase (HDAC) inhibitor, was administered to triple-negative breast cancer (TNBC) cells alone or in combination with epigallocatechin-3-gallate (EGCG), a DNA methyltransferase (DNMT) inhibitor isolated from green tea.

RESULTS

The compounds were able to decrease the expression of cIAP2 while increasing the expression of pro-apoptotic caspase 7. There were also changes in histone modifications, suggesting a role of epigenetic mechanisms in these changes in expression of cIAP2. These changes resulted in an increase in apoptosis. SAHA and EGCG were also capable of limiting TNBC cell migration across a fibronectin (FN) matrix.

CONCLUSION

SAHA and EGCG reduce the metastatic potential of TNBC by inducing the apoptotic pathway.

Comprehensive analysis of differentially expressed serum microRNAs in humans responding to Brucella infection

Background

MicroRNAs (miRNAs), a subset of small non-coding RNA molecules, play crucial roles in various pathophysiological processes. Studies increasingly indicate that dysregulated miRNAs are associated with bacterial infection. Nevertheless, little is known about miRNAs that respond to Brucella infection and their potential clinical value. Our research aimed to identify the serum miRNAs altered during Brucella infection.

Methods

We enrolled serum samples from 73 patients diagnosed with brucellosis and 65 age- and sex-matched control individuals. Illumina sequencing via synthesis (SBS) technology was performed for an initial screen of miRNAs expression profile in serum samples pooled from 29 patients and 29 controls, respectively. A quantitative real-time polymerase chain reaction (qRT-PCR) assay was conducted in the training and validation sets to confirm the concentrations of differentially expressed miRNAs in individual serum samples from 73 patients and 65 controls.

Results

The Illumina SBS technology identified 1,372 known miRNAs and 1,893 novel miRNAs in brucellosis patients. The three markedly upregulated miRNAs (miR-15a-3p, miR-7-2-3p, miR-103b) in brucellosis patients were subsequently validated by qRT-PCR assay, of which miR-103b was confirmed to be significantly and steadily increased in the brucellosis patients compared with the controls (>2-fold, P<0.001). The area under the receiver operating characteristic (ROC) curve (AUC) for miR-103b was 0.714 (95% CI, 0.624-0.804). Bioinformatics analysis predicted that some putative target genes of miR-103b are involved in immune regulation or the processes of apoptosis and autophagy in humans.

Conclusions

The serum miR-103b level markedly increases after Brucella infection and has the potential to serve as an auxiliary diagnostic indicator for Brucella infection that deserves further investigation.