Apoptosis. Its significance in cancer and cancer therapy

Intermolecular Electrostatic Interactions in Cytochrome c Protein Monolayer on Montmorillonite Alumosilicate Surface: A Positive Cooperative Effect

Montmorillonite (MM) crystal nanoplates acquire anticancer properties when coated with the mitochondrial protein cytochrome c (cytC) due to the cancer cells' capability to phagocytize cytC-MM colloid particles. The introduced exogenous cytC initiates apoptosis: an irreversible cascade of biochemical reactions leading to cell death. In the present research, we investigate the organization of the cytC layer on the MM surface by employing physicochemical and computer methods-microelectrophoresis, static, and electric light scattering-to study cytC adsorption on the MM surface, and protein electrostatics and docking to calculate the local electric potential and Gibbs free energy of interacting protein globules. The found protein concentration dependence of the adsorbed cytC quantity is nonlinear, manifesting a positive cooperative effect that emerges when the adsorbed cytC globules occupy more than one-third of the MM surface. Computer analysis reveals that the cooperative effect is caused by the formation of protein associates in which the cytC globules are oriented with oppositely charged surfaces. The formation of dimers and trimers is accompanied by a strong reduction in the electrostatic component of the Gibbs free energy of protein association, while the van der Waals component plays a secondary role.

Nucleobindin 2 inhibits senescence in gastric carcinoma

Here, we focused on the role of Nucleobindin 2 (NUCB2), a multifunctional protein, in gastric carcinoma (GC) progression. NUCB2 expression was investigated in 150 GC cases (20 non-invasive (pT1) and 130 invasive (pT2/pT3/pT4) tumors) by immunohistochemistry (IHC), and in situ hybridization for detection of the mRNA in 21 cases. Using GC cell lines, we determined whether NUCB2 expression was associated with specific cellular phenotypes. In GC clinical samples, NUCB2 was transcriptionally upregulated when compared to normal tissues. High NUCB2 expression was associated with clinicopathological factors including deep tumor invasion, lymphovascular invasion, lymph node metastasis, and advanced clinical stages, and was a significant independent predictor of unfavorable progression-free survival in 150 non-invasive and invasive GC patients. Similar findings were also evident in 72 invasive GC cases in which patients received post-operative chemotherapy, but not in 58 invasive tumors from patients who did not receive the chemotherapy. In cell lines, NUCB2 knockout inhibited proliferation, susceptibility to apoptosis, and migration capability by inducting cellular senescence; this was consistent with higher proliferation and apoptotic indices in the NUCB2 IHC-high compared to NUCB2 IHC-low GC cases. NUCB2-dependent inhibition of senescence in GC engenders aggressive tumor behavior by modulating proliferation, apoptosis, and migration.

Three-Dimensional Structure of Novel Liver Cancer Biomarker Liver Cancer-Specific Serine Protease Inhibitor Kazal (LC-SPIK) and Its Performance in Clinical Diagnosis of Hepatocellular Carcinoma (HCC)

LC-SPIK is a liver cancer-specific isoform of Serine Protease Inhibitor Kazal and has been proposed as a new biomarker for the detection of HCC given its unique 3D structure, which differs from normal pancreatic SPIK. An ELISA technology based on its unique structure was developed to use LC-SPIK as an effective biomarker for the clinical diagnosis of HCC. AFP, the most widely used biomarker for HCC surveillance currently, suffers from poor clinical performance, especially in the detection of early-stage HCC. In one case-control study, which included 164 HCC patients and 324 controls, LC-SPIK had an AUC of 0.87 compared to only 0.70 for AFP in distinguishing HCC from liver disease controls (cirrhosis, HBV/HCV). LC-SPIK also performed significantly better than AFP for the 81 patients with early-stage HCC (BCLC stage 0 and A), with an AUC of 0.85 compared to only 0.61 for AFP. Cirrhosis is the major risk factor for HCC; about 80% of patients with newly diagnosed HCC have preexisting cirrhosis. LC-SPIK's clinical performance was also studied in HCC patients with viral and non-viral cirrhosis, including cirrhosis caused by metabolic dysfunction-associated steatotic liver disease (MASLD) and alcoholic liver disease (ALD). In a total of 163 viral cirrhosis patients with 93 HCC patients (50 early-stage), LC-SPIK had an AUC of 0.85, while AFP had an AUC of 0.70. For patients with early-stage HCC, LC-SPIK had a similar AUC of 0.83, while AFP had an AUC of only 0.60. For 120 patients with nonviral cirrhosis, including 62 HCC (23 early-stage) patients, LC-SPIK had an AUC of 0.84, while AFP had an AUC of only 0.72. For the 23 patients with early-stage HCC, LC-SPIK had a similar AUC of 0.83, while the AUC for AFP decreased to 0.65. All these results suggest that LC-SPIK exhibits significantly better performance in the detection of HCC than AFP in all etiologies of liver diseases. In addition, LC-SPIK accurately detected the presence of HCC in 71-91% of HCC patients with false-negative AFP test results in viral-associated HCC and non-viral-associated HCC.

Ferroptosis and its modulators: A raising target for cancer and Alzheimer's disease

The process of ferroptosis, a recently identified form of regulated cell death (RCD) is associated with the overloading of iron species and lipid-derived ROS accumulation. Ferroptosis is induced by various mechanisms such as inhibiting system Xc, glutathione depletion, targeting excess iron, and directly inhibiting GPX4 enzyme. Also, ferroptosis inhibition is achieved by blocking excessive lipid peroxidation by targeting different pathways. These mechanisms are often related to the pathophysiology and pathogenesis of diseases like cancer and Alzheimer's. Fundamentally distinct from other forms of cell death, such as necrosis and apoptosis, ferroptosis differs in terms of biochemistry, functions, and morphology. The mechanism by which ferroptosis acts as a regulatory factor in many diseases remains elusive. Studying the activation and inhibition of ferroptosis as a means to mitigate the progression of various diseases is a highly intriguing and actively researched topic. It has emerged as a focal point in etiological research and treatment strategies. This review systematically summarizes the different mechanisms involved in the inhibition and induction of ferroptosis. We have extensively explored different agents that can induce or inhibit ferroptosis. This review offers current perspectives on recent developments in ferroptosis research, highlighting the disease's etiology and presenting references to enhance its understanding. It also explores new targets for the treatment of cancer and Alzheimer's disease.

The regulation of inhibitor of apoptosis proteins (IAPs) during the apoptosis of Cotesia chilonis

Inhibitor of apoptosis proteins (IAPs) are crucial components of apoptosis that perform vital roles in the regulation of caspase activity in organisms. In this study, two IAPs genes were identified from Cotesia chilonis, the dominant parasitic wasp of Chilo suppressalis. CcIAP1 gene is a typical IAP and contains two BIR domains and a RING domain, whereas CcIAP gene is an atypical IAP1 only containing two BIR domains. Phylogenetic analysis indicated that CcIAP1 and CcIAP were grouped with other Hymenopteran IAPs and IAP1 in C. suppressalis. Real-time quantitative PCR revealed that CcIAP1 and CcIAP genes were both highly induced at -6°C and 30°C, and expression was highest at the third instar stage. The expression of CcIAP1 and CcIAP genes were significantly induced during parasitism of C. suppressalis, and the 7-d time point resulted in the highest expression levels for both genes, in which was an advanced stage of larval development of C. chilonis. RNAi experiments showed that CcIAP1 gene was the key IAP in the regulation of apoptosis of C. chilonis and its host. In conclusion, CcIAP1 and CcIAP correlate with the development of C. chilonis and their responses to temperature stress.

In-vitro and in-vivo assessment of pH-responsive core-shell nanocarrier system for sequential delivery of methotrexate and 5-fluorouracil for the treatment of breast cancer

Breast cancer (BC) is one of the leading fatal diseases affecting females worldwide. Despite the presence of tremendous chemotherapeutic agents, the resistance emergence directs the recent research towards synergistic drugs' combination along with encapsulation inside biocompatible smart nanocarriers. Methotrexate (MTX) and 5-fluorouracil (Fu) are effective against BC and have sequential synergistic activity. In this study, a core-shell nanocarrier composed of mesoporous silica nanoparticles (MSN) as the core and zeolitic imidazolate framework-8 nano metal organic frameworks (ZIF-8 NMOF) as the shell was developed and loaded with Fu and MTX, respectively. The developed nanostructure; Fu-MSN@MTX-NMOF was validated by several characterization techniques and conferred high drugs' entrapment efficiency (EE%). In-vitro assessment revealed a pH-responsive drug release pattern in the acidic pH where MTX was released followed by Fu. The cytotoxicity evaluation indicated enhanced anticancer effect of the Fu-MSN@MTX-NMOF relative to the free drugs in addition to time-dependent fortified cytotoxic effect due to the sequential drugs' release. The in-vivo anticancer efficiency was examined using Ehrlich ascites carcinoma (EAC) animal model where the anticancer effect of the developed Fu-MSN@MTX-NMOF was compared to the sequentially administrated free drugs. The results revealed enhanced anti-tumor effect while maintaining the normal functions of the vital organs as the heart, kidney and liver.

Recent advances in caspase-3, breast cancer, and traditional Chinese medicine: a review

Caspases (cysteinyl aspartate-specific proteinases) are a group of structurally similar proteases in the cytoplasm that can be involved in cell differentiation, programmed death, proliferation, and inflammatory generation. Experts have found that caspase-3 can serve as a terminal splicing enzyme in apoptosis and participate in the mechanism by which cytotoxic drugs kill cancer cells. Breast cancer (BC) has become the most common cancer among women worldwide, posing a severe threat to their lives. Finding new therapeutic targets for BC is the primary task of contemporary physicians. Numerous studies have revealed the close association between caspase-3 expression and BC. Caspase-3 is essential in BC's occurrence, invasion, and metastasis. In addition, Caspase-3 exerts anticancer effects by regulating cell death mechanisms. Traditional Chinese medicine acting through caspase-3 expression is increasingly used in clinical treatment. This review summarizes the biological mechanism of caspase-3 and research progress on BC. It introduces a variety of traditional Chinese medicine related to caspase-3 to provide new ideas for the clinical treatment of BC.

Current trends in luminescence-based assessment of apoptosis

Apoptosis, the most extensively studied type of cell death, is known to play a crucial role in numerous processes such as elimination of unwanted cells or cellular debris, growth, control of the immune system, and prevention of malignancies. Defective regulation of apoptosis can trigger various diseases and disorders including cancer, neurological conditions, autoimmune diseases and developmental disorders. Knowing the nuances of the cell death type induced by a compound can help decipher which therapy is more effective for specific diseases. The detection of apoptotic cells using classic methods has brought significant contribution over the years, but innovative methods are quickly emerging and allow more in-depth understanding of the mechanisms, aside from a simple quantification. Due to increased sensitivity, time efficiency, pathway specificity and negligible cytotoxicity, these innovative approaches have great potential for both in vitro and in vivo studies. This review aims to shed light on the importance of developing and using novel nanoscale methods as an alternative to the classic apoptosis detection techniques.

Nanosecond pulsed cold atmospheric plasma jet suppresses proliferation and migration of human glioblastoma cells via apoptosis promotion and EMT inhibition

Glioblastoma (GBM) is one of the most aggressive and challenging cancers to treat. Despite extensive research on dozens of cancer cells, including GBM, the effect of cold atmospheric plasma (CAP) on the invasive migration of GBM cells has received limited attention, and the underlying mechanisms remain poorly understood. This study aims to investigate the potential molecular mechanism of ns-CAPJ in inhibiting the invasive migration of human GBM cells. The findings indicate that ns-CAPJ significantly reduces GBM cell invasion and migration, and induces apoptosis in GBM cells. Further mechanistic studies demonstrate a direct correlation between the suppression of the epithelial-mesenchymal transition (EMT) signaling pathway and ns-CAPJ's inhibitory effect on GBM cell invasion and migration. Additionally, combined with the N-acetyl cysteine (NAC, a ROS inhibitor) assay, we found that the ROS stimulated by the ns-CAPJ plays an important role in suppressing the EMT process. This work is expected to provide new insight into understanding the molecular mechanisms of how ns-CAPJ inhibits the proliferation and migration of human GBM cells.

Dual Key-Activated Nir-I/II Fluorescence Probe for Monitoring Photodynamic and Photothermal Synergistic Therapy Efficacy

As cancer markers, hydrogen peroxide (H2 O2 ) and viscosity play an essential role in the development of tumors. Meanwhile, based on the performance of near-infrared (NIR) fluorescence imaging and the high efficiency of photodynamic therapy (PDT) and photothermal therapy (PTT) synergistic therapy, it is urgent to develop a dual-key (H2 O2 and viscosity) activated fluorescence probe for cancer phototherapy. Herein, a NIR-I/II fluorescence probe named BX-B is reported. In the presence of both H2 O2 and viscosity, the fluorescence signal of NIR-I (810 nm) and NIR-II (945 nm) can be released. In the presence of H2 O2 , the PDT and PTT effects are observed. BX-B is used to monitor its therapeutic effects in cancer cells and tumor-bearing mice due to the increased viscosity caused by PDT and PTT. In addition, the tumors of mice treated with BX-B are almost completely ablated after the laser irradiation based on its PDT and PTT synergistic therapy. This work provides a reliable platform for effective cancer treatment and immediate evaluation of therapeutic effects.

Dual anticancer activity of Aspergillus nidulans pigment and Ionizing γ-Radiation on human larynx carcinoma cell line

BACKGROUND

Fungi are a readily available source of naturally generated colored compounds. These compounds might be used as radiosensitizers for treating cancer cells.

METHODS

Aspergillus nidulans was examined for its color-producing ability in Potato dextrose agar (PDA) broth medium. The pigment was characterized by Ultraviolet (UV) spectrophotometer and Gas Chromatography Mass Spectrometry (GC/MS). Pigment extracts from A. nidulans were studied for their cytotoxic effects on the growth of human larynx carcinoma cell line (HEp-2) with or without exposure to γ-radiation at three different doses (5, 10, and 15 Gy). A. nidulans pigment cytotoxic activity was tested against normal Vero cells. Cell apoptosis was studied using flow cytometry. Gene expression of P53, Caspase 3 and Bcl-2 were quantified.

RESULTS

Ultraviolet spectrum and GC/MS revealed the ability of Aspergillus nidulans to produce Rhodopin pigment. HEp-2 cells treated with A. nidulans pigment only give IC50 about 208 µg/ml. In contrast, when treated with the pigment +10 Gy γ-radiation, it give about 115 µg/ml. However, for normal cells, lower cytotoxic activity was detected. Treatment with pigment (208 g/mL) caused about 50% ± 1.0 total apoptosis level and gene expression of P53: 2.3 fold and Caspase 3: 1.84 fold in respect to untreated HEp-2), while Bcl-2 was decreased (Bcl-2: 0.63 fold in respect to untreated HEp-2). Furthermore, treated with pigment (115 µg/mL) + 10Gy caused about 47.41% ± 1.7 total apoptosis level and P53: 2.53 fold and Caspase 3: 2.0 fold in respect to untreated HEp-2, while Bcl-2 was downregulated (Bcl-2: 0.61 fold in respect to untreated HEp-2).

CONCLUSION

This study concluded that the anti-cancer activity of Aspergillus nidulans pigment was enhanced by ionizing radiation at 10 Gy, as well as its low cytotoxic activity against normal Vero cells.

Zinc treatment reverses and anti-Zn-regulated miRs suppress esophageal carcinomas in vivo

Esophageal squamous cell carcinoma (ESCC) is a deadly disease with few prevention or treatment options. ESCC development in humans and rodents is associated with Zn deficiency (ZD), inflammation, and overexpression of oncogenic microRNAs: miR-31 and miR-21. In a ZD-promoted ESCC rat model with upregulation of these miRs, systemic antimiR-31 suppresses the miR-31-EGLN3/STK40-NF-κB-controlled inflammatory pathway and ESCC. In this model, systemic delivery of Zn-regulated antimiR-31, followed by antimiR-21, restored expression of tumor-suppressor proteins targeted by these specific miRs: STK40/EGLN3 (miR-31), PDCD4 (miR-21), suppressing inflammation, promoting apoptosis, and inhibiting ESCC development. Moreover, ESCC-bearing Zn-deficient (ZD) rats receiving Zn medication showed a 47% decrease in ESCC incidence vs. Zn-untreated controls. Zn treatment eliminated ESCCs by affecting a spectrum of biological processes that included downregulation of expression of the two miRs and miR-31-controlled inflammatory pathway, stimulation of miR-21-PDCD4 axis apoptosis, and reversal of the ESCC metabolome: with decrease in putrescine, increase in glucose, accompanied by downregulation of metabolite enzymes ODC and HK2. Thus, Zn treatment or miR-31/21 silencing are effective therapeutic strategies for ESCC in this rodent model and should be examined in the human counterpart exhibiting the same biological processes.

Use of Arabidopsis thaliana as a model to understand specific carcinogenic events: Comparison of the molecular machinery associated with cancer-hallmarks in plants and humans

Model organisms are fundamental in cancer research given that they rise the possibility to characterize in a quantitative-objective fashion the organisms as a whole in ways that are infeasible in humans. From this perspective, model organisms with short generation times and established protocols for genetic manipulation allow the understanding of basic biology principles that might guide carcinogenic onset. The cancer-hallmarks (CHs) approach, a modular perspective for cancer understanding, stands that underlying the variability among different cancer types, critical events support the carcinogenic origin and progression. Thus, CHs as interconnected genetic circuitry, have a causal effect over cancer biogenesis and might represent a comparison scaffold among model organisms to identify and characterize evolutionarily conserved modules to understand cancer. Nevertheless, the identification of novel cancer regulators by comparative genomics approaches relies on selecting specific biological processes or related signaling cascades that limit the type of detected regulators, even more, holistic analysis from a systemic perspective is absent. Similarly, although the plant Arabidopsis thaliana has been used as a model organism to dissect specific disease-associated mechanisms, given the evolutionary distance between plants and humans, a general concern about the utility of using A. thaliana as a cancer model persists. In the present research, we take advantage of the CHs paradigm as a framework to establish a functional systemic comparison between plants and humans, that allowed the identification not only of specific novel key genetic regulators, but also, biological processes, metabolic systems, and genetic modules that might contribute to the neoplastic transformation. We propose five cancer-hallmarks that overlapped in conserved mechanisms and processes between Arabidopsis and human and thus, represent mechanisms which study can be prioritized in A. thaliana as an alternative model for cancer research. Additionally, derived from network analyses and machine learning strategies, a new set of potential candidate genes that might contribute to neoplastic transformation is described. These findings postulate A. thaliana as a suitable model to dissect, not all, but specific cancer properties, highlighting the importance of using alternative complementary models to understand carcinogenesis.

Eldecalcitol inhibits the progression of oral cancer by suppressing the expression of GPx-1

OBJECTIVES

This study aimed to investigate the role of eldecalcitol in the progression of oral squamous cell carcinoma and to explore the related mechanism.

MATERIALS AND METHODS

The effects of eldecalcitol on the proliferation, cell cycle, apoptosis, and migration of oral cancer cells (SCC-15 and CAL-27) were evaluated with cell counting kit-8, flow cytometry, quantitative real-time polymerase chain reaction, western blotting, and scratch assay. Mouse xenograft tumor model was established to further confirm the role of eldecalcitol in the progression of oral cancer. Immunohistochemistry, quantitative real-time polymerase chain reaction, and western blotting were used to detect glutathione peroxidase-1 expression in oral cancer tissue and cells treated with eldecalcitol.

RESULTS

Eldecalcitol was found to inhibit the proliferation and migration of SCC-15 and CAL-27 cells significantly, block the cell cycle in the G0/G1 phase, and enhance the apoptosis. In addition, glutathione peroxidase-1 was downregulated by eldecalcitol and acted as an important medium of eldecalcitol in inhibiting the proliferation and migration of SCC-15 and CAL-27 cells, as well as promoting their apoptosis.

CONCLUSIONS

Eldecalcitol may inhibit the progression of oral cancer by suppressing the expression of glutathione peroxidase-1, which may provide new insight into the application of eldecalcitol as a potential anti-cancer drug.

A Review on Immune-Inspired Node Fault Detection in Wireless Sensor Networks with a Focus on the Danger Theory

The use of fault detection and tolerance measures in wireless sensor networks is inevitable to ensure the reliability of the data sources. In this context, immune-inspired concepts offer suitable characteristics for developing lightweight fault detection systems, and previous works have shown promising results. In this article, we provide a literature review of immune-inspired fault detection approaches in sensor networks proposed in the last two decades. We discuss the unique properties of the human immune system and how the found approaches exploit them. With the information from the literature review extended with the findings of our previous works, we discuss the limitations of current approaches and consequent future research directions. We have found that immune-inspired techniques are well suited for lightweight fault detection, but there are still open questions concerning the effective and efficient use of those in sensor networks.

Modulation of oral cancer and periodontitis using chemotherapeutic agents - A narrative review

Periodontitis, an inflammatory condition, is linked to a higher risk of developing oral cancer. Periodontitis may be a precipitating factor for tumorigenesis and the aggressiveness of specific cancer variants. Although genetics is considered the primary etiologic factor for the development of most cancers, many factors have come to be recognized in the initiation and progression of oral cancer. Consecutively, it is suggestive that periodontitis and oral cancer are distinct disease entities but share common pathogenic mechanisms. Oxidative stress and epigenetic mechanisms are among the most researched mechanisms responsible for initiating apoptotic mechanisms implicated in periodontitis and oral cancer. Current research aims to formulate therapeutic agents to intercede in these mechanisms via host modulation therapy and epigenetic therapy. These advances can revolutionize the treatment of periodontitis and oral cancer. This review aims to shed light on the common pathogenic mechanisms of these diseases and the various host modulation agents that could be beneficial in their treatment.

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.

Flavones: Six Selected Flavones and Their Related Signaling Pathways That Induce Apoptosis in Cancer

Cancer is a horrific disease that, to date, has no cure. It is caused by various factors and takes many lives. Apoptosis is a programmed cell death mechanism and if it does not function correctly in cancer cells, it can lead to severe disease. There are various signaling pathways for regulating apoptosis in cancer cells. Flavonoids are non-artificial natural bioactive compounds that are gaining attention as being capable of for inducing apoptosis in cancer cells. Among these, in this study, we focus on flavones. Flavones are a subclass of the numerous available flavonoids and possess several bioactive functions. Some of the most reported and well-known critical flavones, namely apigenin, acacetin, baicalein, luteolin, tangeretin, and wogonin, are discussed in depth in this review. Our main aim is to investigate the effects of the selected flavones on apoptosis and cell signaling pathways that contribute to death due to various types of cancers.

Effects of Alkanna bracteosa extract on the expression level of HSP90α and HER2 genes in human gastric cancer cell line

Gastric cancer was classified as the third most deadly cancer among all other cancer types. The HSP90 and HER2 genes play essential roles in the stability and function of high-expression proteins that cause malignancy. The aim of this research was to investigate the influence of the alcoholic Alkanna bracteosa extract on the expression of HSP90α and HER2 genes in AGS cell line. Therefore, the methanolic extraction was isolated from aerial parts of the plant and AGS and HuGu cell lines were analyzed using 102.4–0.05 mg ml⁻¹ dose concentrations in serial dilution; to measure the cell toxicity by MTT assay. Furthermore, real-time PCR analysis measured the expression level of HSP90α and HER2 genes using the IC50 dose concentrations. Quantification of apoptosis was analyzed by Annexin/PI kit in flow cytometry and DNA fragmentation tests. The results of MTT assay represented the IC50 dose concentration of 0.8 and 3.2 mg ml⁻¹ for AGS and HuGu respectively. The rate of HER2 gene expression was significantly decreased in AGS cells treated with 0.8 mg ml⁻¹ dose concentration compared to control. The exposure of AGS treated cells with 0.8 mg ml⁻¹ dose concentration after 24 h represented 24.3% apoptosis and 13.3% necrosis. The agarose gel represented the DNA fragmentation pattern of apoptosis. This study demonstrated the significant differences between the cell viability rate, gene expression level, and apoptosis of the Alkanna bracteosa extract on AGS cells. These results demonstrated the first report of which the Alkanna braceteosa would be an effective candidate for possible treatment of Gastric cancer.

Solanum Procumbens-Derived Zinc Oxide Nanoparticles Suppress Lung Cancer In Vitro through Elevation of ROS

Lung cancer is one of the cancers with high mortality rate. The current therapeutic regimens have only limited success rate. The current work highlights the potential of Solanum procumbens-derived zinc oxide nanoparticle (SP-ZnONP)-induced apoptosis in A549 lung cancer cells. Synthesized nanoparticles were confirmed by UV-Vis spectrophotometry, X-ray diffraction (XRD), dynamic light scattering analysis (DLS), scanning electron microscopy (SEM), Fourier transform infrared (FT-IR), and photoluminescence analysis. Lactate dehydrogenase (LDH), cytotoxicity, and cell viability assays revealed that the SP-ZnONP caused the cell death and the inhibition concentration (IC₅₀) was calculated to be 61.28 μg/mL. Treatment with SP-ZnONPs caused morphological alterations in cells, such as rounding, which may have been caused by the substance's impact on integrins. Acridine orange/ethidium bromide dual staining revealed that the cells undergo apoptosis in a dose-dependent manner, which indicates the cell death. Furthermore, reactive oxygen species (ROS) were examined and it was shown that the nanoparticles elevated ROS levels, which led to lipid peroxidation. In short, the SP-ZnONPs increase the level of ROS, which in turn causes lipid peroxidation results in apoptosis. On the other hand, the SP-ZnONPs decrease nitric oxide level in A549 cells in a dose-dependent manner, which also supports the apoptosis. In conclusion, SP-ZnONPs would become a promising treatment option for lung cancer.

Methyl Gallate Suppresses Tumor Development by Increasing Activation of Caspase3 and Disrupting Tumor Angiogenesis in Melanoma

Methyl gallate is a phenolic compound mainly found in medicinal plants. It has been reported to its anticancer activity in various tumors. In this study, we aimed to demonstrate the antitumor effect of methyl gallate in the melanoma mouse model and B16F10 cells. Our results showed that methyl gallate decreased cell viability and induced apoptosis by increasing the expression of cleaved caspase3 in B16F10 cells and prevented cell migration and tube formation in human umbilical vein endothelial cells. In B16F10 cell-inoculated mice, methyl gallate not only decreased tumor volume by 30% but also significantly reduced tumor vessel density and pericyte coverage. Moreover, methyl gallate diminished by close to 50% the expression of cytokeratin and LYVE-1 in mouse right inguinal lymph nodes, indicating that methyl gallate could suppress metastasis. In conclusion, this study suggests that methyl gallate inhibits tumor development by inducing apoptosis and blocking tumor angiogenesis and metastasis and might be considered a therapeutic agent for melanoma.

Cyclophilin A contributes to shikonin-induced glioma cell necroptosis and promotion of chromatinolysis

Shikonin induces glioma cell death via necroptosis, a caspase-independent programmed cell death pathway that is chiefly regulated by receptor-interacting serine/threonine protein kinase1 (RIP1) and 3 (RIP3). Chromatinolysis is considered as one of the key events leading to cell death during necroptosis. It is usually accompanied with nuclear translocation of AIF and formation of γ-H2AX. Cyclophilin A (CypA) is reported to participate in the nuclear translocation of AIF during apoptosis. However, it remains unclear whether CypA contributes to necroptosis and regulation of chromatinolysis. In this study, our results revealed for the first time that shikonin promoted time-dependent CypA activation, which contributed to nuclear translocation of AIF and γ-H2AX formation. In vitro studies showed that knockdown of CypA by siRNA or inhibition of CypA by its specific inhibitor, cyclosporine A (CsA), not only significantly mitigated shikonin-induced glioma cell death, but also prevented chromatinolysis. Mechanistically, activated CypA targeted mitochondria and triggered mitochondrial superoxide overproduction, which then promoted AIF translocation from mitochondria into the nucleus by depolarizing the mitochondria and intensified the formation of γ-H2AX by promoting intracellular accumulation of ROS. Additionally, the CypA in the nucleus can form DNA degradation complexes with AIF and γ-H2AX, which also promote the execution of chromatinolysis. Thus, we demonstrate that CypA contributes to shikonin-induced glioma cell necroptosis and promotion of chromatinolysis.

The Apelin/APLNR system modulates tumor immune response by reshaping the tumor microenvironment

Apelin is an endogenous ligand of the Apelin receptor (APLNR), a seven-transmembrane G protein-coupled receptor, which is widely distributed in human tissue. The Apelin/APLNR system is involved in regulating several physiological and pathological processes. The Apelin expression is increased in a variety of cancer and the Apelin/APLNR system could regulate the development of tumors through mediating autophagy, apoptosis, pyroptosis, and other biological processes to regulate tumor cell proliferation, migration, and invasion. The Apelin/APLNR system also participates in immune response and immune regulation through PI3K-Akt, ERK-MAPK, and other signal pathways. The latest research points out that there is a negative regulatory relationship between APLNR and immune checkpoint PD-L1. In this review, we outline the significance of the Apelin/APLNR signaling pathway in tumorigenesis and its immune regulation. These endeavors provide new insights into the translational application of Apelin/APLNR in cancer and may contribute to the promotion of more effective treatments for cancers.

A multimodal nanoparticles‐based theranostic method and system

We propose a nanoparticles‐based system for the early detection of tumors, treatment under real‐time feedback, and monitoring. The building blocks of the system comprise a few modalities that are integrated into one powerful system which can operate at the patient's bedside in an outpatient clinic setting. The method relies on the unique characteristics of superparamagnetic nanoparticles. It takes advantage of their ability to produce acoustical signals under alternating magnetic fields (AMFs) and to produce heat under these same AMFs with different parameters. It utilizes the nanoparticles' coating for specific binding. The manuscript describes the various parts of this method for localization, source separation, confined heat elevation, triggering of cell death, and monitoring the response to treatment through fluorescence signaling. The entire system continues to evolve into a minimally invasive trans‐endoscopic set‐up.

This article is categorized under:

Diagnostic Tools > In Vivo Nanodiagnostics and Imaging

Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease

Simultaneous Visualization of MiRNA-221 and Caspase-3 in Cancer Cells for Investigating the Feasibility of MiRNA-Targeted Therapy with a Dual-Color Fluorescent Nanosensor

MiRNA-targeted therapy holds great promise for precision cancer therapy. It is important to investigate the effect of changes in miRNA expression on apoptosis in order to evaluate miRNA-targeted therapy and achieve personalized therapy. In this study, we designed a dual-color fluorescent nanosensor consisting of grapheme oxide modified with a molecular beacon and peptide. The nanosensor can simultaneously detect and image miRNA-221 and apoptotic protein caspase-3 in living cells. Intracellular experiments showed that the nanosensor could be successfully applied for in situ monitoring of the effect of miRNA-221 expression changes on apoptosis by dual-color imaging. The current strategy could provide new avenues for investigating the feasibility of miRNA-targeted therapy, screening new anti-cancer drugs targeting miRNA and developing personalized treatment plans.

A Hybrid Imaging Platform(CT/PET/FMI) for Evaluating Tumor Necrosis and Apoptosis in Real-Time

Multimodality imaging is an advanced imaging tool for monitoring tumor behavior and therapy in vivo. In this study, we have developed a novel hybrid tri-modality system that includes two molecular imaging methods: positron emission computed tomography (PET) and fluorescence molecular imaging (FMI) and the anatomic imaging modality X-ray computed tomography (CT). The following paper describes the system development. Also, its imaging performance was tested in vitro (phantom) and in vivo, in Balb/c nude mice bearing a head and neck tumor xenograft treated with novel gene therapy [a new approach to the delivery of recombinant bacterial gene (IL-24-expressing strain)]. Using the tri-modality imaging system, we simultaneously monitored the therapeutic effect, including the apoptotic and necrotic induction within the tumor in vivo. The apoptotic induction was examined in real-time using an 18F-ML-10 tracer; the cell death was detected using ICG. A CT was used to evaluate the anatomical situation. An increased tumor inhibition (including tumor growth and tumor cell apoptosis) was observed in the treatment group compared to the control groups, which further confirmed the therapeutic effect of a new IL-24-expressing strain gene therapy on the tumor in vivo. By being able to offer concurrent morphological and functional information, our system is able to characterize malignant tissues more accurately. Therefore, this new tri-modality system (PET/CT/FMI) is an effective imaging tool for simultaneously investigating and monitoring tumor progression and therapy outcomes in vivo.

Small but Powerful: The Human Vault RNAs as Multifaceted Modulators of Pro-Survival Characteristics and Tumorigenesis

Simple Summary

Small non-protein-coding RNAs have been recognized as valuable regulators of gene expression in all three domains of life. Particularly in multicellular organisms, ncRNAs-mediated gene expression control has evolved as a central principle of cellular homeostasis. Thus, it is not surprising that non-coding RNA misregulation has been linked to various diseases. Here, we review the contributions of the four human vault RNAs to cellular proliferation, apoptosis and cancer biology.

Abstract

The importance of non-coding RNAs for regulating gene expression has been uncovered in model systems spanning all three domains of life. More recently, their involvement in modulating signal transduction, cell proliferation, tumorigenesis and cancer progression has also made them promising tools and targets for oncotherapy. Recent studies revealed a class of highly conserved small ncRNAs, namely vault RNAs, as regulators of several cellular homeostasis mechanisms. The human genome encodes four vault RNA paralogs that share significant sequence and structural similarities, yet they seem to possess distinct roles in mammalian cells. The alteration of vault RNA expression levels has frequently been observed in cancer tissues, thus hinting at a putative role in orchestrating pro-survival characteristics. Over the last decade, significant advances have been achieved in clarifying the relationship between vault RNA and cellular mechanisms involved in cancer development. It became increasingly clear that vault RNAs are involved in controlling apoptosis, lysosome biogenesis and function, as well as autophagy in several malignant cell lines, most likely by modulating signaling pathways (e.g., the pro-survival MAPK cascade). In this review, we discuss the identified and known functions of the human vault RNAs in the context of cell proliferation, tumorigenesis and chemotherapy resistance.

Novel Prognostic Signature for Acute Myeloid Leukemia: Bioinformatics Analysis of Combined CNV-Driven and Ferroptosis-Related Genes

Background: Acute myeloid leukemia (AML), which has a difficult prognosis, is the most common hematologic malignancy. The role of copy number variations (CNVs) and ferroptosis in the tumor process is becoming increasingly prominent. We aimed to identify specific CNV-driven ferroptosis-related genes (FRGs) and establish a prognostic model for AML.

Methods: The combined analysis of CNV differential data and differentially expressed genes (DEGs) data from The Cancer Genome Atlas (TCGA) database was performed to identify key CNV-driven FRGs for AML. A risk model was constructed based on univariate and multivariate Cox regression analysis. The Gene Expression Omnibus (GEO) dataset was used to validate the model. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were conducted to clarify the functional roles of DEGs and CNV-driven FRGs.

Results: We identified a total of 6828 AML-related DEGs, which were shown to be significantly associated with cell cycle and immune response processes. After a comprehensive analysis of CNVs and corresponding DEGs and FRGs, six CNV-driven FRGs were identified, and functional enrichment analysis indicated that they were involved in oxidative stress, cell death, and inflammatory response processes. Finally, we screened 2 CNV-driven FRGs (DNAJB6 and HSPB1) to develop a prognostic risk model. The overall survival (OS) of patients in the high-risk group was significantly shorter in both the TCGA and GEO (all p < 0.05) datasets compared to the low-risk group.

Conclusion: A novel signature based on CNV-driven FRGs was established to predict the survival of AML patients and displayed good performance. Our results may provide potential targets and new research ideas for the treatment and early detection of AML.

RNF7 inhibits apoptosis and sunitinib sensitivity and promotes glycolysis in renal cell carcinoma via the SOCS1/JAK/STAT3 feedback loop

Background

RING finger protein 7 (RNF7) is a highly conserved protein that functions as an E3 ubiquitin ligase. RNF7 overexpression is indicated in multiple human cancers, but its role in renal cell carcinoma (RCC) and the mechanisms underlying how it regulates the initiation and progression of RCC have not been explored.

Methods

Bioinformatics analysis, quantitative reverse-transcription polymerase chain reaction (RT-PCR), and Western blot were conducted to determine the expression of RNF7 in RCC tissues and cell lines. Knockdown and overexpression experiments were performed to examine the effects of RNF7 on cell viability, apoptosis, and glycolysis in vitro and on tumor growth in nude mice in vivo.

Results

The elevated RNF7 expression in tumor tissues of patients with RCC was correlated with poor survival. RNF7 overexpression inhibited apoptosis and promoted glycolysis in vitro and increased tumor growth in vivo by activating the JAK/STAT3 signaling pathway by ubiquitination of SOCS1. Moreover, RNF7 overexpression affected the sensitivity of RCC cells to sunitinib. Finally, STAT3 activation was necessary for transcriptional induction of RNF7.

Conclusion

These results demonstrate that RNF7 inhibited apoptosis, promoted glycolysis, and inhibited sunitinib sensitivity in RCC cells via ubiquitination of SOCS1, thus activating STAT3 signaling. These suggest the potential for targeting the RNF7-SOCS1/JAK/STAT3 pathway for RCC treatment.

Supplementary Information

The online version contains supplementary material available at 10.1186/s11658-022-00337-5.

Antifungal activity of dexamethasone against fluconazole-resistant Candida albicans and its activity against biofilms

Objective: The present study investigated the antifungal action of dexamethasone disodium phosphate (Dex). Methodology: Susceptibility testing was performed using the Clinical & Laboratory Standards Institute protocol; M27-A3, checkerboard test and biofilm were evaluated with two isolates of Candida albicans, hyphal production test, molecular docking analysis and flow cytometry analysis. Result: Dex and fluconazole (FLC) together had a synergistic effect. Mature biofilm was reduced when treated with Dex alone or in combination. Dex and FLC promoted a decrease in the production of hyphae and changes in the level of mitochondrial depolarization, increased generation of reactive oxygen species, loss of membrane integrity, increased phosphatidylserine externalization and molecular docking; there was interaction with ALS3 and SAP5 targets. Conclusion: Dex showed antifungal activity against FLC-resistant C. albicans strains.

A "Self-Checking" pH/Viscosity-Activatable NIR-II Molecule for Real-Time Evaluation of Photothermal Therapy Efficacy

We present a second near-infrared (NIR-II) self-checking molecule, LET-1052, for acidic tumor microenvironment (TME) turn-on photothermal therapy (PTT), followed by viscosity based therapeutic efficacy evaluation by itself in two independent channels, denoted as "self-checking" strategy. In acidic TME, LET-1052 was protonated and turned on NIR-II absorption for PTT under 1064 nm laser irradiation. Subsequently, PTT-induced cellular death increases intracellular viscosity, which inhibited the intramolecular rotation of LET-1052, resulting in the enhancement of NIR-I fluorescence for real-time evaluation of PTT efficacy. After PTT of tumor-bearing mice for different periods of NIR-II laser irradiation, NIR-I fluorescence in the tumor region showed positive correlation with tumor growth inhibition rate, demonstrating reliable and prompt prediction of PTT efficacy. The strategy may be expanded for instant evaluation of other therapeutic modalities for personalized medicine.

Apoptotic and Antiproliferative Potential of GAPDH from Mallotus philippensis Seed on Human Lung Carcinoma: In Vitro and In Vivo Approach

Aim:

The anticancer potential of a purified seed protein from Mallotus philippensis is scientifically evaluated and reported here.

Background:

Seeds of Mallotus philippensis are used to treat various diseases in the indigenous systems of medicine in India.

Objectives:

The present study deals with the isolation, purification, identification, and screening of protein of interest that exhibit maximum activity against lung cancer cells from the seed crude protein of Mallotus philippensis.

Methods:

Size-exclusion with HPLC was used to purify crude protein (15 mg) from M. philippensis seeds. Protein of interest was identified using the LC-MS/MS method and analyzed by in vitro (A549 cell lines) in vivo (B16-F10 cells from melanoma cancer-induced Wistar rats) to estimate anticancer activity.

Results:

SDS-PAGE was applied to isolate and purify elution III (480 μg/ml). Elution III LCMS/ MS data were used to search the UniProt database and were eventually matched with glyceraldehyde 3-phosphate dehydrogenase (GAPDH). MTT assay of GAPDH-treated A549 cells exhibited an IC50 of 3.03 ± 0.39 μg (24 h) and 1.93 ± 0.19 μg (48 h). AO/EtBr staining showed early and late apoptotic characteristics such as cell membrane blebbing, chromatin condensation, and the formation of apoptotic bodies. Hoechst staining confirmed the death of cells by exhibiting bright blue fluorescent, condensed, and fragmented nuclei. GAPDH-treated rats by 10 and 20 mg/kg bw significantly increased body weight by 29.50 ± 3.06 and 31.33 ± 2.69, respectively, and decreased melanoma metastasis in the lungs by 66.79% and 86.57%, respectively. Further, GAPDH treatment significantly increased the levels of SOD, CAT, and GPx and reduced GST and GSH. Histopathological analysis confirmed nuclear alteration in the lung tissue of the treated groups only.

Conclusion:

Apoptotic potential of GAPDH against lung carcinoma has been confirmed in the present investigation.

Platinum prodrug nanoparticles inhibiting tumor recurrence and metastasis by concurrent chemoradiotherapy

Background

Although concurrent chemoradiotherapy (CRT), as one of the most effective antineoplastic therapies in clinic, can successfully inhibit the growth of tumor cells, a risk of developing secondary tumor is still an insurmountable barrier in clinical practice.

Results

Herein, a new platinum prodrug composed of tannic acid (TA) and Pt²⁺ (TA-Pt) complex film was synthesized on the surface of Fe₂O₃ nanoparticles (NPs) with excellent stability and biocompatibility for enhanced CRT. In this system, TA-Pt complex could respond to the tumor acidic microenvironment and damage the DNA of tumor cells. Moreover, the internal iron core not only improved the effect of subsequent radiotherapy (RT), but also disrupted the iron balance in cells, inducing intracellular ferroptosis and eliminating apoptosis-resistant cells. In vitro and vivo experimental results indicated that more than 90% of tumor cells were depleted and more than 75% of the cured tumor-bearing mice evinced no recurrence or metastasis.

Conclusions

This work offered a new idea for combining the effective chemotherapy, RT and ferroptosis therapy to enhance the curative effect of CRT and inhibit tumor recurrence and metastasis.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s12951-022-01322-y.

Functional interaction between S100A1 and MDM2 may modulate p53 signaling in normal and malignant endometrial cells

BACKGROUND

S100A1 expression is deregulated in a variety of human malignancies, but its role in normal and malignant endometrial cells is unclear.

METHODS

We used endometrial carcinoma (Em Ca) cell lines to evaluate the physical and functional interaction of S100A1 with p53 and its negative regulator, mouse double minute 2 (MDM2). We also evaluated the expression of S100A1, p53, and MDM2 in clinical samples consisting of 89 normal endometrial and 189 Em Ca tissues.

RESULTS

S100A1 interacted with MDM2 but not p53 in Em Ca cell lines. Treatment of cells stably overexpressing S100A1 with Nutlin-3A, an inhibitor of the p53/MDM2 interaction, increased expression of p53-target genes including p21^waf1 and BAX. S100A1 overexpression enhanced cellular migration, but also sensitized cells to the antiproliferative and proapoptotic effects of Adriamycin, a genotoxic agent; these phenotypes were abrogated when S100A1 was knocked down using shRNA. In clinical samples from normal endometrium, S100A1 expression was significantly higher in endometrial glandular cells of the middle/late secretory and menstrual stages when compared to cells in the proliferative phases; high S100A1 was also positively correlated with expression of MDM2 and p21^waf1 and apoptotic status, and inversely correlated with Ki-67 scores. However, such correlations were absent in Em Ca tissues.

CONCLUSION

The interaction between S100A1 and MDM2 may modulate proliferation, susceptibility to apoptosis, and migration through alterations in p53 signaling in normal- but not malignant-endometrial cells.

Suppression of colorectal carcinogenesis by naringin

BACKGROUND

Colorectal cancer is the third most malignant cancer worldwide. Despite novel treatment options, the incidence and mortality rates of colon cancer continue to increase in most countries, especially in US, European and Asian countries. Colorectal carcinogenesis is multifactorial, including dietary and genetic factors, as well as lacking physical activity. Vegetables and fruits contain high amounts of secondary metabolites, which might reduce the risk for colorectal carcinogenesis. Flavonoids are important bioactive polyphenolic compounds. There are more than 4,000 different flavonoids, including flavanones, flavonoids, isoflavonoids, flavones, and catechins in a large variety of plant.

HYPOTHESIS

Among various other flavonoids, naringin in Citrus fruits has been a subject of intense scrutiny for its activity against many types of cancer, including colorectal cancer. We hypothesize that naringin is capable to inhibit the growth of transformed colonocytes and to induce programmed cell death in colon cancer cells.

RESULTS

We comprehensively review the inhibitory effects of naringin on colorectal cancers and address the underlying mechanistic pathways such as NF-κB/IL-6/STAT3, PI3K/AKT/mTOR, apoptosis, NF-κB-COX-2-iNOS, and β-catenin pathways.

CONCLUSION

Naringin suppresses colorectal inflammation and carcinogenesis by various signaling pathways. Randomized clinical trials are needed to determine their effectiveness in combating colorectal cancer.

Don’t dust off the dust! – A facile synthesis of graphene quantum dots derived from indoor dust towards their cytotoxicity and antibacterial activity

This study presents a feasible and sustainable way for producing crystalline graphene quantum dots derived from indoor dust particles using a simple eco-friendly hydrothermal procedure.

Regio- and stereoselective synthesis and evaluation of densely functionalized bispiro[oxindole-isoxazole-indandione] hybrids as anticancer agents

This is the combination of three key pharmacophores through bispiro quaternary carbon atoms and evaluation of their anticancer activity.

The efficiency of photothermal action of gold shell-isolated nanoparticles against tumor cells depends on membrane interactions

Photoinduced hyperthermia with nanomaterials has been proven effective in photothermal therapy (PTT) of tumor tissues, but a precise control in PTT requires determination of the molecular-level mechanisms. In this paper, we determined the mechanisms responsible for the action of photoexcited gold shell-isolated nanoparticles (AuSHINs) in reducing the viability of MCF7 (glandular breast cancer) and especially A549 (lung adenocarcinoma) cells in vitro experiments, while the photoinduced damage to healthy cells was much smaller. The photoinduced effects were more significant than using other nanomaterials, and could be explained by the different effects from incorporating AuSHINs on Langmuir monolayers from lipid extracts of tumoral (MCF7 and A549) and healthy cells. The incorporation of AuSHINs caused similar expansion of the Langmuir monolayers, but Fourier-transform infrared spectroscopy (FTIR) data of Langmuir-Schaefer films (LS) indicated distinct levels of penetration into the monolayers. AuSHINs penetrated deeper into the A549 extract monolayers, affecting the vibrational modes of polar groups and carbon chains, while in MCF7 monolayers penetration was limited to the surroundings of the polar groups. Even smaller insertion was observed for monolayers of the healthy cell extract. The photochemical reactions were modulated by AuSHINs penetration, since upon irradiation the surface area of A549 monolayer decreased owing to lipid chain cleavage by oxidative reactions. For MCF7 monolayers, hydroperoxidation under illumination led to a ca. 5% increase in surface area. The monolayers of healthy cell lipid extract were barely affected by irradiation, consistent with the lowest degree of AuSHINs insertion. In summary, efficient photothermal therapy may be devised by producing AuSHINs capable of penetrating the chain region of tumor cell membranes.

Evaluation of the anticarcinogenic potential of the endophyte, Streptomyces sp. LRE541 isolated from Lilium davidii var. unicolor (Hoog) Cotton

BACKGROUND

Endophytic actinomycetes, as emerging sources of bioactive metabolites, have been paid great attention over the years. Recent reports demonstrated that endophytic streptomycetes could yield compounds with potent anticancer properties that may be developed as chemotherapeutic drugs.

RESULTS

Here, a total of 15 actinomycete-like isolates were obtained from the root tissues of Lilium davidii var. unicolor (Hoog) Cotton based on their morphological appearance, mycelia coloration and diffusible pigments. The preliminary screening of antagonistic capabilities of the 15 isolates showed that isolate LRE541 displayed antimicrobial activities against all of the seven tested pathogenic microorganisms. Further in vitro cytotoxicity test of the LRE541 extract revealed that this isolate possesses potent anticancer activities with IC50 values of 0.021, 0.2904, 1.484, 4.861, 6.986, 8.106, 10.87, 12.98, and 16.94 μg/mL against cancer cell lines RKO, 7901, HepG2, CAL-27, MCF-7, K562, Hela, SW1990, and A549, respectively. LRE541 was characterized and identified as belonging to the genus Streptomyces based on the 16S rRNA gene sequence analysis. It produced extensively branched red substrate and vivid pink aerial hyphae that changed into amaranth, with elliptic spores sessile to the aerial mycelia. To further explore the mechanism underlying the decrease of cancer cell viability following the LRE541 extract treatment, cell apoptosis and cell cycle arrest assays were conducted in two cancer cell lines, RKO and 7901. The result demonstrated that LRE541 extract inhibited cell proliferation of RKO and 7901 by causing cell cycle arrest both at the S phase and inducing apoptosis in a dose-dependent manner. The chemical profile of LRE541 extract performed by the UHPLC-MS/MS analysis revealed the presence of thirty-nine antitumor compounds in the extract. Further chemical investigation of the LRE541 extract led to the discovery of one prenylated indole diketopiperazine (DKP) alkaloid, elucidated as neoechinulin A, a known antitumor agent firstly detected in Streptomyces; two anthraquinones 4-deoxy-ε-pyrromycinone (1) and epsilon-pyrromycinone (2) both displaying anticancer activities against RKO, SW1990, A549, and HepG2 with IC50 values of 14.96 ± 2.6 - 20.42 ± 4.24 μg/mL for (1); 12.9 ± 2.13, 19.3 ± 4.32, 16.8 ± 0.75, and 18.6 ± 3.03 μg/mL for (2), respectively.

CONCLUSION

Our work evaluated the anticarcinogenic potential of the endophyte, Streptomyces sp. LRE541 and obtained one prenylated indole diketopiperazine alkaloid and two anthraquinones. Neoechinulin A, as a known antitumor agent, was identified for the first time in Streptomyces. Though previously found in Streptomyces, epsilon-pyrromycinone and 4-deoxy-ε-pyrromycinone were firstly shown to possess anticancer activities.

Synergistic growth-inhibition effect of quercetin and N-Acetyl-L-cysteine against HepG2 cells relying on the improvement of quercetin stability

In this study, N-Acetyl-l-cysteine (NAC) as a widely-used antioxidant was first applied to improve the stability of Que in medium. The stability of Que in medium was analyzed, and the growth-inhibition effect of Que and NAC against HepG2 cells was estimated. The results showed NAC could significantly improve the stability of Que in medium (more than 80%), while Que alone in medium was totally degraded within 4 h. Besides, it was found that Que together with NAC could significantly enhance the growth-inhibition effect against HepG2 cells compared with Que alone, with the IC₅₀ value of 40 μM and 200 μM for Que together with NAC and Que alone. Moreover, NAC could inhibit the depletion of GSH induced by Que. The synergistic growth-inhibition effect of Que and NAC against HepG2 cells was attributed to NAC improving Que stability in medium accompanied by NAC inhibiting the depletion of GSH induced by Que. The results showed that NAC could improve the stability of Que and reduce the degradation rate of Que in culture medium. This study can provide a reference for the further study of the mechanism of NAC enhancing the stability of quercetin and the development of broad-spectrum stabilizers.

Difference in the binding mechanisms of ABT-263/43b with Bcl-xL/Bcl-2: computational perspective on the accurate binding free energy analysis

B-cell lymphoma/leukemia gene-2(Bcl-2) protein family known for regulating cell cycle arrest and subsequent cell death is highly expressed in a variety of cancers. Among them, the Bcl-xL and Bcl-2 are two essential proteins in the Bcl-2 family. In the present work, the differences in binding modes as between the two proteins and two ligands ABT-263/43b were investigated and compared. And the computational alanine scanning combined with the recently developed interaction entropy (AS-IE) method was employed for predicting their binding free energies and finding those amino acids that were more critical during the binding process. The result showed that the binding free energy calculated by the AS-IE method was more in line with experimental values than the molecular mechanics/Poisson-Boltzmann surface area (MM/PBSA) method. Besides, no significant difference was found between Bcl-xL and ABT-263/43b in the binding free energy, which Bcl-xL showed slightly weaker binding free energy to 43b because of the fewer number of key residues with interactions. Nonetheless, compared with the Bcl-2 and 43b complex, the Bcl-2 and ABT-263 system had greater number of key residues interacting with ABT-263, in particular, contribute favorably, resulting in a stronger binding ability for the Bcl-2 and ABT-263 systems. The van der Waals and hydrogen bond contributions were significant in the four protein-ligand complexes. Overall, Tyr108 was found to be the common key residues in the Bcl-xL-ligand complex, while Tyr105, Glu100, and Glu143 were established as the common key residue in the Bcl-2-ligand systems. We hope that the predicted hot spot residues and their energy distributions can guide the design of peptide and small-molecule drugs targeting Bcl-xL and Bcl-2.

Nicotinamide N-Methyltransferase: An Emerging Protagonist in Cancer Macro(r)evolution

Nicotinamide N-methyltransferase (NNMT) has progressed from being considered merely a Phase II metabolic enzyme to one with a central role in cell function and energy metabolism. Over the last three decades, a significant body of evidence has accumulated which clearly demonstrates a central role for NNMT in cancer survival, metastasis, and drug resistance. In this review, we discuss the evidence supporting a role for NNMT in the progression of the cancer phenotype and how it achieves this by driving the activity of pro-oncogenic NAD+-consuming enzymes. We also describe how increased NNMT activity supports the Warburg effect and how it promotes oncogenic changes in gene expression. We discuss the regulation of NNMT activity in cancer cells by both post-translational modification of the enzyme and transcription factor binding to the NNMT gene, and describe for the first time three long non-coding RNAs which may play a role in the regulation of NNMT transcription. We complete the review by discussing the development of novel anti-cancer therapeutics which target NNMT and provide insight into how NNMT-based therapies may be best employed clinically.

CDC20 regulates the cell proliferation and radiosensitivity of P53 mutant HCC cells through the Bcl-2/Bax pathway

Purpose: The incidence of hepatocellular carcinoma (HCC) is extremely high, and China accounts for approximately 50% of global liver cancer cases. Previous studies reported that CDC20 is involved in the occurrence and progression of a variety of malignant tumors. So, whether CDC20 will affect the development of HCC, we have conducted in-depth research on this. Methods: We selected Hep3B and HepG2 for cell culture, and performed siRNA transfection, lentiviral infection, western blot, MTS determination, cell cycle determination, apoptosis test, immunodeficiency test, clone survival test and subcutaneous parthenogenesis in nude mice. Results: Knockdown of CDC20 greatly enhanced the radiation efficacy on the growth retardation in HepG2, and protein level of CDC20 was decreased for the activation of P53 by radiation. Downregulation of CDC20 combined with radiation can inhibit proliferation, aggravate DNA damage, increase G2/M arrest, and promote apoptosis of HCC cells to a greater extent, and the relative survival fraction of HCC cells was gradually reduced with radiation dose increased in P53 mutated Hep3B cells. After knocking down CDC20 in HCC, Bcl-2 was down-regulated and Bax expression increased. Down-regulation of CDC20 can inhibit further invasion by promoting the radiosensitivity of HCC. Conclusion: In this study, we found that that CDC20 was highly expressed in HCC and participated in radio resistance of HCC cells with P53 mutation Bcl-2/Bax via signaling pathway. This study is the first to present evidence that CDC20 may play a role in improving the efficacy of radiotherapy in HCC.

Cytoplasmic EBP50 and elevated PARP1 are unfavorable prognostic factors in ovarian clear cell carcinoma

Patients with ovarian clear cell carcinoma (OCCC) experience frequent recurrence, which is most likely due to chemoresistance. We used shotgun proteomics analysis and identified upregulation of ezrin-binding phosphoprotein 50 (EBP50) in recurrent OCCC samples. Cytoplasmic and/or nuclear (Cyt/N), but not membranous, EBP50 immunoreactivity was significantly higher in recurrent OCCC as compared to that of primary tumors. OCCC cells expressing cytoplasmic EBP50 were significantly less susceptible to cisplatin (CDDP)-induced apoptosis compared to cells expressing membranous EBP50. Abrogation of resistance following knockdown of cytoplasmic EBP50 was accompanied by decreased XIAP and BCL2, increased BAX and increased caspase-3 cleavage. We found that poly (ADP-ribose) polymerase1 (PARP1), which is involved in DNA damage detection and repair, binds to EBP50 through its PDZ1 domain. CDDP treatment of cells expressing cytoplasmic (but not membranous) EBP50 increased nuclear PARP1 expression, whereas knockdown of EBP50 cells decreased PARP1 expression and activity following CDDP treatment. Finally, OCCC patients with a combination of Cyt/N EBP50 and high PARP1 score had worst the prognosis for overall and progression-free survival. Together, our data suggest that cytoplasmic EBP50 inhibits apoptosis and promotes OCCC survival through stabilization of PARP1 activity and modulation of the XIAP/BCL2/BAX axis. This may increase the likelihood of tumor recurrence, and we therefore suggest a combined analysis for EBP50 and PARP1 may have great utility in OCCC prediction and prognosis.

Evolution and Structure of API5 and Its Roles in Anti-Apoptosis

Apoptosis, also named programmed cell death, is a highly conserved physiological mechanism. Apoptosis plays crucial roles in many life processes, such as tissue development, organ formation, homeostasis maintenance, resistance against external aggression, and immune responses. Apoptosis is regulated by many genes, among which Apoptosis Inhibitor-5 (API5) is an effective inhibitor, though the structure of API5 is completely different from the other known Inhibitors of Apoptosis Proteins (IAPs). Due to its high expression in many types of tumors, API5 has received extensive attention, and may be an effective target for cancer treatment. In order to comprehensively and systematically understand the biological roles of API5, we summarized the evolution and structure of API5 and its roles in anti-apoptosis in this review.