Beyond Death: Unmasking the Intricacies of Apoptosis Escape

Apoptosis, or programmed cell death, maintains tissue homeostasis by eliminating damaged or unnecessary cells. However, cells can evade this process, contributing to conditions such as cancer. Escape mechanisms include anoikis, mitochondrial DNA depletion, cellular FLICE inhibitory protein (c-FLIP), endosomal sorting complexes required for transport (ESCRT), mitotic slippage, anastasis, and blebbishield formation. Anoikis, triggered by cell detachment from the extracellular matrix, is pivotal in cancer research due to its role in cellular survival and metastasis. Mitochondrial DNA depletion, associated with cellular dysfunction and diseases such as breast and prostate cancer, links to apoptosis resistance. The c-FLIP protein family, notably CFLAR, regulates cell death processes as a truncated caspase-8 form. The ESCRT complex aids apoptosis evasion by repairing intracellular damage through increased Ca2+ levels. Antimitotic agents induce mitotic arrest in cancer treatment but can lead to mitotic slippage and tetraploid cell formation. Anastasis allows cells to resist apoptosis induced by various triggers. Blebbishield formation suppresses apoptosis indirectly in cancer stem cells by transforming apoptotic cells into blebbishields. In conclusion, the future of apoptosis research offers exciting possibilities for innovative therapeutic approaches, enhanced diagnostic tools, and a deeper understanding of the complex biological processes that govern cell fate. Collaborative efforts across disciplines, including molecular biology, genetics, immunology, and bioinformatics, will be essential to realize these prospects and improve patient outcomes in diverse disease contexts.

Identification of Fangjihuangqi Decoction as a late-stage autophagy inhibitor with an adjuvant anti-tumor effect against non-small cell lung cancer

BACKGROUND

Clinically, although chemotherapy is one of the most commonly used methods of treating tumors, chemotherapeutic drugs can induce autophagic flux and increase tumor cell resistance, leading to drug tolerance. Therefore, theoretically, inhibiting autophagy may improve the efficacy of chemotherapy. The discovery of autophagy regulators and their potential application as adjuvant anti-cancer drugs is of substantial importance. In this study, we clarified that Fangjihuangqi Decoction (FJHQ, traditional Chinese medicine) is an autophagy inhibitor, which can synergistically enhance the effect of cisplatin and paclitaxel on non-small cell lung cancer (NSCLC) cells.

METHODS

We observed the changes of autophagy level in NSCLC cells under the effect of FJHQ, and verified the level of the autophagy marker protein and cathepsin. Apoptosis was detected after the combination of FJHQ with cisplatin or paclitaxel, and NAC (ROS scavenger) was further used to verify the activation of ROS-MAPK pathway by FJHQ.

RESULTS

We observed that FJHQ induced autophagosomes in NSCLC cells and increased the levels of P62 and LC3-II protein expression in a concentration- and time-gradient-dependent manner, indicating that autophagic flux was inhibited. Co-localization experiments further showed that while FJHQ did not inhibit autophagosome and lysosome fusion, it affected the maturation of cathepsin and thus inhibited the autophagic pathway. Finally, we found that the combination of FJHQ with cisplatin or paclitaxel increased the apoptosis rate of NSCLC cells, due to increased ROS accumulation and further activation of the ROS-MAPK pathway. This synergistic effect could be reversed by NAC.

CONCLUSION

Collectively, these results demonstrate that FJHQ is a novel late-stage autophagy inhibitor that can amplify the anti-tumor effect of cisplatin and paclitaxel against NSCLC cells.

Dual role of quercetin in enhancing the efficacy of cisplatin in chemotherapy and protection against its side effects: a review

Chemotherapy has opened a new window in cancer therapy. However, the resistance of cancer cells has dramatically reduced the efficacy of chemotherapy. Cisplatin is a chemotherapeutic agent and its potential in cancer therapy has been restricted by resistance of cancer cells. As a consequence, the scientists have attempted to find new strategies in elevating chemotherapy efficacy. Due to great anti-tumour activity, naturally occurring compounds are of interest in polychemotherapy. Quercetin is a flavonoid with high anti-tumour activity against different cancers that can be used with cisplatin to enhance its efficacy and also are seen to sensitise cancer cells into chemotherapy. Furthermore, cisplatin has side effects such as nephrotoxicity and ototoxicity. Administration of quercetin is advantageous in reducing the adverse effects of cisplatin without compromising its anti-tumour activity. In this review, we investigate the dual role of quercetin in enhancing anti-tumour activity of cisplatin and simultaneous reduction in its adverse effects.

The role of BCL-2 family proteins in regulating apoptosis and cancer therapy

Apoptosis, as a very important biological process, is a response to developmental cues or cellular stress. Impaired apoptosis plays a central role in the development of cancer and also reduces the efficacy of traditional cytotoxic therapies. Members of the B-cell lymphoma 2 (BCL-2) protein family have pro- or anti-apoptotic activities and have been studied intensively over the past decade for their importance in regulating apoptosis, tumorigenesis, and cellular responses to anticancer therapy. Since the inflammatory response induced by apoptosis-induced cell death is very small, at present, the development of anticancer drugs targeting apoptosis has attracted more and more attention. Consequently, the focus of this review is to summarize the current research on the role of BCL-2 family proteins in regulating apoptosis and the development of drugs targeting BCL-2 anti-apoptotic proteins. Additionally, the mechanism of BCL-2 family proteins in regulating apoptosis was also explored. All the findings indicate the potential of BCL-2 family proteins in the therapy of cancer.

Investigation of the effect of Prunus Amygdalus Amara on the expression of some genes of apoptosis and immortality in breast cancer cells (MCF-7)

BACKGROUND

Anti-cancer effects of almond nuts or oil have been approved, but there are a few pieces of research that have evaluated, in detail, almond and other seeds' effects on cancer. Therefore, in the present project, the aim was to explore the regulatory effect of the bitter almond extract (Prunus amygdalus Batsch) on the apoptotic and anti-cancer potency of MCF-7 cells.

OBJECTIVES

In the current experimental research, the Almond effect on MCF7 cells was evaluated by investigating the expression and the balance between Bcl-2, Bax genes to unmark the potential molecular mechanism.

METHODS

For 24 and 48h, the MCF7 cells were treated with the bitter almond extract (187.5-3000 µg/mL). MTT assay was used to assess the viability, and Real-time-PCR was applied to determine the expression of Bax and Bcl-2, facing β-actin.

RESULTS

Our results revealed a significant difference between different extract concentrations on the viability of MCF7 cell lines in 24 and 48 h; cell viability decreased time-dependently (P < 0.05). After 24 and 48h of extract facing MCF7 cells, the evaluated IC50 value was 3000 and 1500 µg/mL, respectively. Based on Real Time-PCR analysis, after 24 and 48 h, the mRNA levels of BCL-2 decreased by the extract, whereas BAX was in the MCF-7 cell line.

CONCLUSION

From the results, it can be concluded that bitter almond extract has anti-cancer properties that may influence the apoptotic pathways by regulating relative gene expression.

lncRNA XIST knockdown suppresses hypoxia/reoxygenation (H/R)-induced apoptosis of H9C2 cells by regulating miR-545-3p/G3BP2

This study was aimed at determining the roles and functions of lncRNA XIST/miR-545-3p/G3BP2 axis during hypoxia/reoxygenation (H/R)-induced H9C2 cell apoptosis. H9C2 cells were distributed into two groups, the H/R injury and control groups. High-throughput lncRNA sequencing was applied in the determination of differentially expressed lncRNAs between H/R-induced H9C2 cells and normal H9C2 cells. Real-time polymerase chain reactions (RT-PCR) were used to confirm the expression levels of lncRNA XIST in H/R-induced H9C2 cells. H9C2 cells were then transfected with lncRNA XIST recombinant plasmid (lncRNA XIST), sh-LINC XIST, agomiR-545-3p, antagomiR-545-3p, pcDNA-G3BP2, sh-G3BP2, and a corresponding negative control (NC). Bioinformatic analyses revealed that MiR-545-3p was a target for lncRNA XIST. This finding was confirmed by dual-luciferase reporter assay. The degree of cell apoptosis was evaluated by a flow cytometer. RT-PCR and western blot were performed to assess the apoptotic-related proteins in each group. A total of 859 differentially expressed lncRNAs (up-regulated = 502, down-regulated = 357) were identified. LncRNA XIST was found to be down-regulated in H/R-induced H9C2 cells while miR-545-3p was distinctly up-regulated. miR-545-3p was established to be a direct target for LncRNA XIST. LncRNA XIST significantly enhanced the apoptotic rate, while its inhibition suppressed the apoptotic rate. AgomiR-545-3p partially blocked the lncRNA XIST and enhanced the apoptosis of H/R-induced H9C2 cells. Moreover, miR-545-3p was shown to be a direct target for G3BP2. The overexpression of G3BP2 partially reversed the apoptotic effects of miR-545-3p on H/R-induced H9C2 cells. lncRNA XIST/miR-545-3p/GBP2 was found to be an apoptotic regulator in H/R-induced H9C2 cells.

PNO1 regulates autophagy and apoptosis of hepatocellular carcinoma via the MAPK signaling pathway

Some studies have reported that activated ribosomes are positively associated with malignant tumors, especially in hepatocellular carcinoma (HCC). The RNA-binding protein PNO1 is a critical ribosome rarely reported in human tumors. This study aimed to explore the molecular mechanisms of PNO1 in HCC. Using 150 formalin-fixed and paraffin-embedded samples and 8 fresh samples, we found high PNO1 expression in HCC tumor tissues through Western blotting and RT-PCR. Moreover, the higher PNO1 expression was associated with poor HCC prognosis patients. In vitro and in vivo experiments indicated that PNO1 overexpression promoted the proliferation and depressed the apoptosis of HCC cells. High PNO1 expression also increased the autophagy of HCC cells. The molecular mechanisms underlying PNO1 were examined by RNA-seq analysis and a series of functional experiments. Results showed that PNO1 promoted HCC progression through the MAPK signaling pathway. Therefore, PNO1 was overexpressed in HCC, promoted autophagy, and inhibited the apoptosis of HCC cells through the MAPK signaling pathway.

A novel therapeutic strategy for hepatocellular carcinoma: Immunomodulatory mechanisms of selenium and/or selenoproteins on a shift towards anti-cancer

Selenium (Se) is an essential trace chemical element that is widely distributed worldwide. Se exerts its immunomodulatory and nutritional activities in the human body in the form of selenoproteins. Se has increasingly appeared as a potential trace element associated with many human diseases, including hepatocellular carcinoma (HCC). Recently, increasing evidence has suggested that Se and selenoproteins exert their immunomodulatory effects on HCC by regulating the molecules of oxidative stress, inflammation, immune response, cell proliferation and growth, angiogenesis, signaling pathways, apoptosis, and other processes in vitro cell studies and in vivo animal studies. Se concentrations are generally low in tissues of patients with HCC, such as blood, serum, scalp hair, and toenail. However, Se concentrations were higher in HCC patient tissues after Se supplementation than before supplementation. This review summarizes the significant relationship between Se and HCC, and details the role of Se as a novel immunomodulatory or immunotherapeutic approach against HCC.