Current overview on the clinical update of Bcl-2 anti-apoptotic inhibitors for cancer therapy

Albumin nanocomplex of BCL-2/xL inhibitor reduced platelet toxicity and improved anticancer efficacy in myeloproliferative neoplasm and lymphoma

The clinical application of BCL-2/xL inhibitors for cancer treatment is limited by the on-target thrombocytopenia. Although APG-1252 was designed to mitigate this issue, platelet toxicity at higher doses in clinical trials restricts dose escalation for greater efficacy. We have developed albumin nanocomplexes of APG-1252 (Nano-1252) to reduce platelet toxicity while improving drug efficacy through enhancing drug delivery to lymphoid organs. Nano-1252 forms stable nanoparticles due to the strong binding affinity between APG-1252 and albumin, reducing the platelet toxicity threshold by fourfold by limiting premature drug release and conversion to its active forms in circulation. Furthermore, Nano-1252 exhibited preferential accumulation in lymphoid organs, leading to enhanced anticancer efficacy in Mantle Cell Lymphoma (MCL) and Myeloproliferative Neoplasms (MPNs) mouse models. Our study not only develops a potential formulation to overcome the current translational barrier of APG-1252 but also reveals novel properties of the well-established albumin nanoformulation, thereby expanding its clinical applications.

Design, Synthesis, and Anti-Prostate Cancer Potential of 2-(4-Nitrobenzyl) Malonates In Vitro and DAL Acute Oral Toxicity Assessment In Vivo

New 4-nitrobenzyl derivatives were designed and synthesised by nucleophilic substitution reactions of 4-nitrobenzyl bromide with malonic acid and its derivatives. The synthesised molecules were characterised using mass analysis and spectroscopic techniques and tested for their antioxidant properties using various methods, such as nitric oxide, DPPH, and hydrogen peroxide radical scavenging methods. The anti-inflammatory activities of the molecules were assessed using RBC membrane stabilisation and albumin denaturation methods. We evaluated the compounds' potential anti-prostate cancer activity using the DU145 cell line. The MTT assay determined the cell viability, indicating good anti-proliferative activity. The molecule 3 c exhibited the highest potency, with a CTC50 of 11.83 μg/mL. Molecular dynamics simulations were performed to study the stability of the ligand within the protein after docking and the resulting protein-ligand complex. The in vivo analysis of molecule 3 c in the DAL xenograft model demonstrated promising results. The increase in life span, reduction in tumor volume, and comparable effects to standard drugs are encouraging features that suggest that molecule 3 c may possess significant potential as an anti-cancer agent. The research also implies that these molecules might be potential lead compounds for developing new prostate cancer drugs.

Targeting Bcl-2 with Indole Scaffolds: Emerging Drug Design Strategies for Cancer Treatment

The B-cell lymphoma-2 (Bcl-2) protein family plays a crucial role as a regulator in the process of apoptosis. There is a substantial body of evidence indicating that the upregulation of antiapoptotic Bcl-2 proteins is prevalent in several cancer cell lines and original tumour tissue samples. This phenomenon plays a crucial role in enabling tumour cells to avoid apoptosis, hence facilitating the development of resistant cells against chemotherapy. Therefore, the success rate of chemotherapy for cancer can be enhanced by the down-regulation of anti-apoptotic Bcl-2 proteins. Furthermore, the indole structural design is commonly found in a variety of natural substances and biologically active compounds, particularly those that possess anti-cancer properties. Due to its distinctive physicochemical and biological characteristics, it has been highly regarded as a fundamental framework in the development and production of anti-cancer drugs. As a result, a considerable range of indole derivatives, encompassing both naturally occurring and developed compounds, have been identified as potential candidates for the treatment of cancer. Several of these derivatives have advanced to clinical trials, while others are already being used in clinical settings. This emphasizes the significant role of indole in the field of research and development of anti-cancer therapeutics. This study provides an overview of apoptosis and the structural characteristics of Bcl-2 family proteins, and mainly examines the present stage and recent developments in Bcl-2 inhibitors with an indole scaffold embedded in their structure.

Therapeutic potential of dietary bioactive compounds against anti-apoptotic Bcl-2 proteins in breast cancer

Breast cancer remains a leading cause of cancer-related mortality among women worldwide. One of its defining features is resistance to apoptosis, driven by aberrant expression of apoptosis-related proteins, notably the overexpression of anti-apoptotic Bcl-2 proteins. These proteins enable breast cancer cells to evade apoptosis and develop resistance to chemotherapy, underscoring their critical role as therapeutic targets. Diet plays a significant role in breast cancer risk, potentially escalating or inhibiting cancer development. Recognizing the limitations of current treatments, extensive research is focused on exploring bioactive compounds derived from natural sources such as plants, fruits, vegetables, and spices. These compounds are valued for their ability to exert potent anticancer effects with minimal toxicity and side effects. While literature extensively covers the effects of various dietary compounds in inducing apoptosis in cancer cells, comprehensive information specifically on how dietary bioactive compounds modulate anti-apoptotic Bcl-2 protein expression in breast cancer is limited. This review aims to provide a comprehensive understanding of the interaction between Bcl-2 proteins and caspases in the regulation of apoptosis, as well as the impact of dietary bioactive compounds on the modulation of anti-apoptotic Bcl-2 in breast cancer. It further explores how these interactions influence breast cancer progression and treatment outcomes.

Overview of BH3 mimetics in ovarian cancer

Ovarian carcinoma is the leading cause of gynecological cancer-related death, still with a dismal five-year prognosis, mainly due to late diagnosis and the emergence of resistance to cytotoxic and targeted agents. Bcl-2 family proteins have a key role in apoptosis and are associated with tumor development/progression and response to therapy in different cancer types, including ovarian carcinoma. In tumors, evasion of apoptosis is a possible mechanism of resistance to therapy. BH3 mimetics are small molecules that occupy the hydrophobic pocket on pro-survival proteins, allowing the induction of apoptosis, and are currently under study as single agents and/or in combination with cytotoxic and targeted agents in solid tumors. Here, we discuss recent advances in targeting anti-apoptotic proteins of the Bcl-2 family for the treatment of ovarian cancer, focusing on BH3 mimetics, and how these approaches could potentially offer an alternative/complementary way to treat patients and overcome or delay resistance to current treatments.

TTI-101 targets STAT3/c-Myc signaling pathway to suppress cervical cancer progression: an integrated experimental and computational analysis

BACKGROUND

Cervical cancer (CC) is a significant global health concern, demanding the consideration of novel therapeutic strategies. The signal transducer and activator of transcription 3 (STAT3) pathway has been implicated in cancer progression and is a potential target for therapeutic intervention. This study aimed to explore the therapeutic potential of TTI-101, a small molecule STAT3 inhibitor, in CC and investigate its underlying mechanisms.

METHODS

Molecular docking studies and molecular dynamics simulations were performed to explore the binding interaction between TTI-101 and STAT3 and assess the stability of the STAT3-TTI-101 complex. Cell viability assays, wound healing assays, colony formation assays, flow cytometry analysis, and gene expression analysis were conducted. In vivo xenograft models were used to assess the antitumor efficacy of TTI-101.

RESULTS

The in silico analysis shows a stable binding interaction between TTI-101 and STAT3. TTI-101 treatment inhibits cell viability, clonogenic ability, and cell migration in CC cells. Furthermore, TTI-101 induces apoptosis and cell cycle arrest. Analysis of apoptosis-related markers demonstrated dysregulation of Bax, Bcl-2, and Caspase-3 upon TTI-101 treatment. Moreover, TTI-101 caused G2/M phase arrest accompanied by a decrease in CDK1 and Cyclin B1 at mRNA levels. In the xenograft model, TTI-101 significantly inhibited tumor growth without adverse effects on body weight.

CONCLUSION

TTI-101 exhibited anticancer effects by targeting the STAT3/c-Myc signaling pathway, inducing cell cycle arrest, and promoting apoptosis in CC cells. These findings provide valuable insights into the development of novel therapeutic strategies for cervical cancer. Further investigation is warranted to validate the clinical application of TTI-101.

Co-delivery of artemisinin and metformin via PEGylated niosomal nanoparticles: potential anti-cancer effect in treatment of lung cancer cells

PURPOSE

Despite the advances in treatment, lung cancer is a global concern and necessitates the development of new treatments. Biguanides like metformin (MET) and artemisinin (ART) have recently been discovered to have anti-cancer properties. As a consequence, in the current study, the anti-cancer effect of MET and ART co-encapsulated in niosomal nanoparticles on lung cancer cells was examined to establish an innovative therapy technique.

METHODS

Niosomal nanoparticles (Nio-NPs) were synthesized by thin-film hydration method, and their physicochemical properties were assessed by FTIR. The morphology of Nio-NPs was evaluated with FE-SEM and AFM. The MTT assay was applied to evaluate the cytotoxic effects of free MET, free ART, their encapsulated form with Nio-NPs, as well as their combination, on A549 cells. Apoptosis assay was utilized to detect the biological processes involved with programmed cell death. The arrest of cell cycle in response to drugs was assessed using a cell cycle assay. Following a 48-h drug treatment, the expression level of hTERT, Cyclin D1, BAX, BCL-2, Caspase 3, and 7 genes were assessed using the qRT-PCR method.

RESULTS

Both MET and ART reduced the survival rate of lung cancer cells in the dose-dependent manner. The IC50 values of pure ART and MET were 195.2 μM and 14.6 mM, respectively while in nano formulated form their IC50 values decreased to 56.7 μM and 78.3 μM, respectively. The combination of MET and ART synergistically decreased the proliferation of lung cancer cells, compared to the single treatments. Importantly, the combination of MET and ART had a higher anti-proliferative impact against A549 lung cancer cells, with lower IC50 values. According to the result of Real-time PCR, hTERT, Cyclin D1, BAX, BCL-2, Caspase 3, and Caspase 7 genes expression were considerably altered in treated with combination of nano formulated MET and ART compared to single therapies.

CONCLUSION

The results of this study showed that the combination of MET and ART encapsulated in Nio-NPs could be useful for the treatment of lung cancer and can increase the efficiency of lung cancer treatment.

Folic/lactobionic acid dual-targeted polymeric nanocapsules for potential treatment of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a malignant tumor that affects many patients diagnosed with hepatic cell inflammation and liver cirrhosis. Targeted polymeric nanocapsules could facilitate the internalization and accumulation of anticancer drugs. Dual-targeted folic acid/lactobionic acid-poly lactic co-glycolic acid nanocapsules (NCs) were prepared and loaded with pterostilbene (PTN) and characterized for their physicochemical properties, as well as in vitro and in vivo anticancer activity. NCs displayed a size of 222 nm, zeta potential of - 16.5 mV, and sustained release for 48 h. The IC50 of PTN NCs (5.87 ± 0.8 µg/mL) was 20 times lower than unencapsulated PTN (121.26 ± 9.42 µg/mL) on HepG2 liver cancer cells owing to the enhanced cellular uptake of the former, as delineated by flow cytometry. In vivo study on HCC-induced animals delineated the superiority of the dual-targeted NCs over the unencapsulated PTN, which significantly reduced the liver markers ALT, AST, and ALP, as well as the tumor-related markers AFP and Bcl2, and elevated the anti-apoptotic marker caspase 3. Furthermore, the NCs significantly reduced the oxidative stress and exhibited almost comparable histological features to the normal group. Therefore, it can be concluded that the dual-ligated folic acid/lactobionic acid nanocapsules can be considered a promising potential treatment option for hepatocellular carcinoma.

In-silico characterization of LSDV132 protein divulged its BCL-2-like nature

Lumpy skin disease virus (LSDV) belongs to Poxviridae family. This virus possesses various proteins which impart potential functions to it including assembly of newly synthesized viruses in the replication cycle and forming their structure. LSDV132 protein is also one of such proteins. Its key characteristics were unknown because, no any relevant study was reported about it. This study aimed to investigate its characteristic features and essential functions using several bioinformatics techniques. These analyses included physiochemical characterization and exploring the crucial functional and structural perspectives. Upon analysis of the physiochemical properties, the instability index was computed to be 30.89% which proposed LSDV132 protein to be a stable protein. Afterwards, the phosphorylation sites were explored. Several sites were found in this regard which led to the hypothesis that it might be involved in the regulation of apoptosis and cell signaling, among other cellular processes. Furthermore, the KEGG analysis and the analysis of protein family classification confirmed that the LSDV132 protein possessed Poxvirus-BCL-2-like motifs, indicating that it might be responsible in modulating the apoptosis of host cells. This crucial finding suggested that the protein under study possessed BCL-2-like features. Proceeding this very important finding, the molecular docking analysis was performed. In this context, various viral BCL-2 inhibitors were retrieved from the ChEMBL database for docking purpose. The docking results revealed that pelcitoclax exhibited best docking scores i.e., -9.1841 kcal/mol, among all of the other docked complexes. This fact signified that this compound might serve as an inhibitor of LSDV132 protein.

Recent trends and advances in novel formulations as an armament in Bcl-2/Bax targeted breast cancer

Breast cancer (BC) remains a significant health burden worldwide, necessitating the development of innovative therapeutic strategies. The B-cell lymphoma 2 (Bcl-2) family proteins, Bcl-2 and Bax, play a crucial role in regulating apoptosis and thus are promising targets for BC therapy. We focus on the recent advancements in novel formulations that specifically target Bcl-2/Bax pathway to combat BC. It provides an overview on biological functions of Bcl-2/Bax in apoptosis regulation, emphasizing their significance in pathogenesis and progression of the disease while covering the numerous therapeutic approaches aimed at modulating the Bcl-2/Bax pathway, including small-molecule inhibitors, peptides, gene-based therapies and other repurposed drugs harboured onto cutting-edge technologies and nanocarrier systems employed to enhance the targeted delivery of Bcl-2/Bax inhibitors tumor cells. These advanced formulations aim to improve therapeutic efficacy, minimize off-target effects, and overcome drug resistance, offering promising prospects in its treatment. In conclusion, it illuminates the diverse and evolving landscape of novel formulations as an essential armament in targeting these proteins while bridging and unravelling the obscurity of Bcl-2/Bax pathway-targeted drug delivery systems which are presently in their nascent stages of exploration for BC therapy which can benefit researchers, clinicians, and pharmaceutical scientists.

Targeting Antheraea pernyi silk fibroin modified dual-gene coexpressing vector enhances gene transport and promotes lung tumor suppression

Poor systemic administration capability, a natural tendency to target CAR-positive cells, nonspecific shedding to normal organs, and poor viral persistence in tumor tissues are major hindrances to the therapeutic benefit of adenovirus (Ad) gene vectors in the clinical setting. Antheraea pernyi silk fibroin (ASF) grafted with targeted peptides was used to coat ING4-IL-24 dual-gene coexpressing adenovirus for targeted gene therapy of lung carcinoma. The dual-gene vector with a diameter of 390 nm could target and infect H460 lung tumor cells, internalize into cells, express the ING4 and IL-24 genes at a high level, effectively inhibit the proliferation of lung tumor cells, and induce their apoptosis. The in vivo treatment of H460 human lung carcinoma xenograft tumors showed that the dual-gene coexpressing vector suppressed the proliferation of lung tumor cells by downregulating the expression of Ki67 and Bcl-2, promoted apoptosis by upregulating the expression of C Caspase-3 and Bax, and blocked tumor angiogenesis by downregulating the expression of VEGF and CD31, thus exerting a multichannel tumor inhibition effect. Surface modification of Ad with targeted cationic silk fibroin is an effective way to solve the natural tendencies and in vivo instability of adenovirus vectors, and such vectors have potential for clinical application.

Mild Uncoupling of Mitochondria Synergistically Enhances Senolytic Specificity and Sensitivity of BH3 Mimetics

Despite immense potential as anti-aging interventions, applications of current senolytics are limited due to low sensitivity and specificity. We demonstrate the specific loss of complex I-linked coupled respiration and the inability to maintain mitochondrial membrane potential upon respiratory stimulation as a specific vulnerability of senescent cells. Further decreasing the mitochondrial membrane potential of senescent cells with a mitochondrial uncoupler synergistically enhances the in vitro senolytic efficacy of BH3 mimetic drugs, including Navitoclax, by up to two orders of magnitude, whereas non-senescent cells remain unaffected. Moreover, a short-term intervention combining the mitochondrial uncoupler BAM15 with Navitoclax at a dose two orders of magnitude lower than typically used rescues radiation-induced premature aging in an in vivo mouse model, as demonstrated by reduced frailty and improved cognitive function for at least eight months. Our study shows compromised mitochondrial functional capacity is a senescence-specific vulnerability that can be targeted by mild uncoupling in vitro and in vivo.

Effect of photodynamic therapy mediated by hematoporphyrin derivatives on small cell lung cancer H446 cells and bronchial epithelial BEAS-2B cells

To investigate the effects of photodynamic therapy (PDT) mediated by hematoporphyrin derivatives (HPD) on the proliferation of small cell lung cancer H446 cells and bronchial epithelial BEAS-2B cells. H446 cells and BEAS-2B cells were cultured in vitro with different concentrations of HPD(0, 5, 10, 12, 15, 20 μg/mL) for 4 h, and then irradiated with 630 nm laser with different energy densities (0, 25, 50, 75, 100 mW/cm2). Cell viability of H446 cells and BEAS-2B cells were detected by CCK8 assay. The cell apoptosis was observed with Annexin V-FTTC/PI double staining and Hoechst 33258. The RT-PCR examination was applied to detect the transcriptional changes of the mRNA of Bax、Bcl-2, and Caspase-9. The results of CCK8 showed that when the HPD was 15 μg/mL and the laser power density reached 50 mW/cm2, the cell viability was significantly decreased compared with the black control group. Hoechst 33258 staining showed that with the increase of HPD concentration, the cell density was reduced, and apoptotic cells increased. Flow cytometry assay revealed that the apoptotic rates of the HPD-PDT group of H446 cells and BEAS-2B cells were significantly different from those of the blank control group. The RT-PCR examination showed that the expression levels of Bax and Caspase-9 mRNA in the HPD-PDT group were up-regulated, while the expression levels of Bcl-2 mRNA were down-regulated significantly. HPD-PDT can inhibit H446 cells and BEAS-2B cells growth. The mechanism may be related to up-regulating the expression levels of Bax and Caspase-9 mRNA and down-regulating the expression levels of Bcl-2 mRNA.

Clinical Characteristics and Local Histopathological Modulators of Endometriosis and Its Progression

Endometriosis (E) and adenomyosis (A) are associated with a wide spectrum of symptoms and may present various histopathological transformations, such as the presence of hyperplasia, atypia, and malignant transformation occurring under the influence of local inflammatory, vascular and hormonal factors and by the alteration of tumor suppressor proteins and the inhibition of cell apoptosis, with an increased degree of lesion proliferation.

MATERIAL AND METHODS

This retrospective study included 243 patients from whom tissue with E/A or normal control uterine tissue was harvested and stained by histochemical and classical immunohistochemical staining. We assessed the symptomatology of the patients, the structure of the ectopic epithelium and the presence of neovascularization, hormone receptors, inflammatory cells and oncoproteins involved in lesion development. Atypical areas were analyzed using multiple immunolabeling techniques.

RESULTS

The cytokeratin (CK) CK7+/CK20- expression profile was present in E foci and differentiated them from digestive metastases. The neovascularization marker cluster of differentiation (CD) 34+ was increased, especially in areas with malignant transformation of E or A foci. T:CD3+ lymphocytes, B:CD20+ lymphocytes, CD68+ macrophages and tryptase+ mast cells were abundant, especially in cases associated with malignant transformation, being markers of the proinflammatory microenvironment. In addition, we found a significantly increased cell division index (Ki67+), with transformation and inactivation of tumor suppressor genes p53, B-cell lymphoma 2 (BCL-2) and Phosphatase and tensin homolog (PTEN) in areas with E/A-transformed malignancy.

CONCLUSIONS

Proinflammatory/vascular/hormonal changes trigger E/A progression and the onset of cellular atypia and malignant transformation, exacerbating symptoms, especially local pain and vaginal bleeding. These triggers may represent future therapeutic targets.

Advances in molecular targeted therapies to increase efficacy of (chemo)radiation therapy

Recent advances in understanding the tumor's biology in line with a constantly growing number of innovative technologies have prompted characterization of patients' individual malignancies and may display a prerequisite to treat cancer at its patient individual tumor vulnerability. In recent decades, radiation- induced signaling and tumor promoting local events for radiation sensitization were explored in detail, resulting the development of novel molecular targets. A multitude of pharmacological, genetic, and immunological principles, including small molecule- and antibody-based targeted strategies, have been developed that are suitable for combined concepts with radiation (RT) or chemoradiation therapy (CRT). Despite a plethora of promising experimental and preclinical findings, however, so far, only a very limited number of clinical trials have demonstrated a better outcome and/or patient benefit when RT or CRT are combined with targeted agents. The current review aims to summarize recent progress in molecular therapies targeting oncogenic drivers, DNA damage and cell cycle response, apoptosis signaling pathways, cell adhesion molecules, hypoxia, and the tumor microenvironment to impact therapy refractoriness and to boost radiation response. In addition, we will discuss recent advances in nanotechnology, e.g., RNA technologies and protein-degrading proteolysis-targeting chimeras (PROTACs) that may open new and innovative ways to benefit from molecular-targeted therapy approaches with improved efficacy.

Mechanisms of action of the BCL-2 inhibitor venetoclax in multiple myeloma: a literature review

Abnormal cellular apoptosis plays a pivotal role in the pathogenesis of Multiple Myeloma (MM). Over the years, BCL-2, a crucial anti-apoptotic protein, has garnered significant attention in MM therapeutic research. Venetoclax (VTC), a small-molecule targeted agent, effectively inhibits BCL-2, promoting the programmed death of cancerous cells. While VTC has been employed to treat various hematological malignancies, its particular efficacy in MM has showcased its potential for broader clinical applications. In this review, we delve into the intricacies of how VTC modulates apoptosis in MM cells by targeting BCL-2 and the overarching influence of the BCL-2 protein family in MM apoptosis regulation. Our findings highlight the nuanced interplay between VTC, BCL-2, and MM, offering insights that may pave the way for optimizing therapeutic strategies. Through this comprehensive analysis, we aim to lay a solid groundwork for future explorations into VTC's clinical applications and the profound effects of BCL-2 on cellular apoptosis.

Cancer Resistance Is Mediated by the Upregulation of Several Anti-Apoptotic Gene Products via the Inducible Nitric Oxide Synthase/Nitric Oxide Pathway: Therapeutic Implications

Significance: Several therapeutic strategies for cancer treatments have been developed with time, and significant milestones have been achieved recently. However, with these novel therapies, not all cancer types respond and in the responding cancer types only a subset is affected. The failure to respond is principally the result that these cancers develop several mechanisms of resistance. Thus, a focus of current research investigations is to unravel the various mechanisms that regulate resistance and identify suitable targets for new therapeutics. Recent Advances: Hence, many human cancer types have been reported to overexpress the inducible nitric oxide synthase (iNOS) and it has been suggested that iNOS/nitric oxide (NO) plays a pivotal role in the regulation of resistance. We have postulated that iNOS overexpression or NO regulates the overexpression of pivotal anti-apoptotic gene products such as B-cell lymphoma 2 (Bcl-2), B-cell lymphoma extra large (Bcl-xL), myeloid cell leukemia-1 (Mcl-1), and survivin. In this report, we describe the various mechanisms, transcriptional, post-transcriptional, and post-translational, by which iNOS/NO regulates the expression of the above anti-apoptotic gene products. Critical Issues: The iNOS/NO-mediated regulation of the four gene products is not the same with both specific and overlapping pathways. Our findings are, in large part, validated by bioinformatic analyses demonstrating, in several cancers, several direct correlations between the expression of iNOS and each of the four examined anti-apoptotic gene products. Future Directions: We have proposed that targeting iNOS may be highly efficient since it will result in the underexpression of multiple anti-apoptotic proteins and shifting the balance toward the proapoptotic gene products and reversal of resistance. Antioxid. Redox Signal. 39, 853-889.

Cowanin induces apoptosis in breast cancer cells via Bcl-2 signaling pathway

OBJECTIVES

This study aimed to investigate the effect of cowanin the mechanism of cowanin toward cell death and BCL-2 protein (antiapoptotic) expression of T47D breast cancer.

METHODS

The cell death was evaluated by double staining, namely acridine orange and propidium iodide, and then observed under a fluorescence microscope. Meanwhile, the BCL-2 protein expression was determined by western blotting with measurement of protein area and protein density.

RESULTS

The result found T47D breast cancer cells were viable, apoptosis, and necrosis after treatment with cowanin. The average viable cells, apoptosis, and necrosis percentages were 54.13 %, 45.43 %, and 0.44 %, respectively. Statistical analysis showed cowanin could significantly induce death in T47D breast cancer cells by apoptosis (p<0.05). It was also revealed that cowanin and positive control (doxorubicin) treatment had a significantly decreased protein area and protein density (p<0.05).

CONCLUSIONS

It can be concluded that cowanin can induce death in T47D breast cancer cells by apoptosis and affect the expression of Bcl-2 protein in T47D breast cancer cells.

Antagonizing the irreversible thrombomodulin-initiated proteolytic signaling alleviates age-related liver fibrosis via senescent cell killing

Cellular senescence is a stress-induced, stable cell cycle arrest phenotype which generates a pro-inflammatory microenvironment, leading to chronic inflammation and age-associated diseases. Determining the fundamental molecular pathways driving senescence instead of apoptosis could enable the identification of senolytic agents to restore tissue homeostasis. Here, we identify thrombomodulin (THBD) signaling as a key molecular determinant of the senescent cell fate. Although normally restricted to endothelial cells, THBD is rapidly upregulated and maintained throughout all phases of the senescence program in aged mammalian tissues and in senescent cell models. Mechanistically, THBD activates a proteolytic feed-forward signaling pathway by stabilizing a multi-protein complex in early endosomes, thus forming a molecular basis for the irreversibility of the senescence program and ensuring senescent cell viability. Therapeutically, THBD signaling depletion or inhibition using vorapaxar, an FDA-approved drug, effectively ablates senescent cells and restores tissue homeostasis in liver fibrosis models. Collectively, these results uncover proteolytic THBD signaling as a conserved pro-survival pathway essential for senescent cell viability, thus providing a pharmacologically exploitable senolytic target for senescence-associated diseases.

The human immune cell simulated anti-breast cancer nanorobot: the efficient, traceable, and dirigible anticancer bio-bot

Background

Various types of cancer therapy strategies have been investigated and successfully applied so far. There are a few modern strategies for improving drug selectivity and biocompatibility, such as nanoparticle-based drug delivery systems. Herein, we designed the traceable enzyme-conjugated magnetic nanoparticles to target human breast cancer cells by simulating the innate immune cell’s respiratory explosion response.

Methods

The human immune cell simulated anti-breast cancer-nanorobot (hisABC-NB) was produced by conjugating the mouse-derived iNOS and human-originated MPO enzymes on the folate-linked chitosan-coated Fe3O4 nanoparticles. The synthesized nanoparticles were functionalized with folic acid as the breast cancer cell detector. Then, the hisABC-NB’s stability and structural properties were characterized by studying Zeta-potential, XRD, FTIR, VSM, FESEM, and DLS analysis. Next, the selectivity and anti-tumor activity of the hisABC-NB were comparatively analyzed on both normal (MCF-10) and cancerous (MCF-7) human breast cells by analyzing the cells’ survival, apoptotic gene expression profile (P53, BAX, BCL2), and flow cytometry data. Finally, the hisABC-NB’s traceability was detected by T2-weighted MRI imaging on the balb-c breast tumor models.

Results

The hisABC-NB significantly reduced the MCF-7 human breast cancer cells by inducing apoptosis response and arresting the cell cycle at the G2/M phase compared with the normal cell type (MCF-10). Moreover, the hisABC-NB exhibited a proper MRI contrast at the tumor region of treated mice compared with the non-treated type, which approved their appropriate MRI-mediated traceability.

Conclusion

The hisABC-NB’s traceability, dirigibility, and selective cytotoxicity were approved, which are the three main required factors for an efficient anticancer compound. Therefore, it has the potential to be used as an intelligent safe anticancer agent for human breast cancer treatment. However, several in vitro and in vivo studies are required to clarify its selectivity, stability, and safety.

A novel BH3 mimetic Bcl-2 inhibitor promotes autophagic cell death and reduces in vivo Glioblastoma tumor growth

Anti-apoptotic members of the Bcl-2 family proteins play central roles in the regulation of cell death in glioblastoma (GBM), the most malignant type of brain tumor. Despite the advances in GBM treatment, there is still an urgent need for new therapeutic approaches. Here, we report a novel 4-thiazolidinone derivative BH3 mimetic, BAU-243 that binds to Bcl-2 with a high affinity. BAU-243 effectively reduced overall GBM cell proliferation including a subpopulation of cancer-initiating cells in contrast to the selective Bcl-2 inhibitor ABT-199. While ABT-199 successfully induces apoptosis in high BCL2-expressing neuroblastoma SHSY-5Y cells, BAU-243 triggered autophagic cell death rather than apoptosis in GBM A172 cells, indicated by the upregulation of BECN1, ATG5, and MAP1LC3B expression. Lc3b-II, a potent autophagy marker, was significantly upregulated following BAU-243 treatment. Moreover, BAU-243 significantly reduced tumor growth in vivo in orthotopic brain tumor models when compared to the vehicle group, and ABT-199 treated animals. To elucidate the molecular mechanisms of action of BAU-243, we performed computational modeling simulations that were consistent with in vitro results. Our results indicate that BAU-243 activates autophagic cell death by disrupting the Beclin 1:Bcl-2 complex and may serve as a potential small molecule for treating GBM.

Role of lncRNA MIAT/miR-361-3p/CCAR2 in prostate cancer cells

The study was aimed to investigate the role and mechanism of long non-coding RNAs (lncRNA) myocardial infarction-associated transcript (MIAT) in prostate cancer. The relationships between lncRNA MIAT and miR-361-3p, miR-361-3p and cell cycle and apoptosis regulator 2 (CCAR2) were predicted by StarBase and TargetScan, and verified by dual-luciferase reporter assay and RNA pull-down assay. Quantitative real-time PCR assay was performed to detect the mRNA expression of lncRNA MIAT, miR-361-3p, CCAR2, Bax, and Bcl-2 in the prostate cancer tissues or cells. The protein levels of CCAR2, Bax, and Bcl-2 were detected by Western blot analysis. The cell viability and apoptosis were detected by MTT assay and Flow cytometry analysis, respectively. lncRNA MIAT was upregulated, while miR-361 was downregulated in the prostate cancer tissues and Du145 cells. lncRNA MIAT negatively regulated miR-361-3p expression in Du145 cells. Downregulating lncRNA MIAT decreased the cell viability, induced the cell apoptosis, increased Bax expression, and decreased Bcl-2 expression in Du145 cells, while the effects were reversed by downregulating miR-361-3p or CCAR2 upregulation. Moreover, CCAR2 upregulation reversed the effects of miR-361-3p upregulation on Du145 cell viability and apoptosis. In conclusion, lncRNA MIAT participated in prostate cancer by regulating cell proliferation and apoptosis via miR-361-3p/CCAR2 axis.

The NF-κB Pharmacopeia: Novel Strategies to Subdue an Intractable Target

NF-κB transcription factors are major drivers of tumor initiation and progression. NF-κB signaling is constitutively activated by genetic alterations or environmental signals in many human cancers, where it contributes to almost all hallmarks of malignancy, including sustained proliferation, cell death resistance, tumor-promoting inflammation, metabolic reprogramming, tissue invasion, angiogenesis, and metastasis. As such, the NF-κB pathway is an attractive therapeutic target in a broad range of human cancers, as well as in numerous non-malignant diseases. Currently, however, there is no clinically useful NF-κB inhibitor to treat oncological patients, owing to the preclusive, on-target toxicities of systemic NF-κB blockade. In this review, we discuss the principal and most promising strategies being developed to circumvent the inherent limitations of conventional IκB kinase (IKK)/NF-κB-targeting drugs, focusing on new molecules that target upstream regulators or downstream effectors of oncogenic NF-κB signaling, as well as agents targeting individual NF-κB subunits.

Mcl-1 levels critically impact the sensitivities of human colorectal cancer cells to APG-1252-M1, a novel Bcl-2/Bcl-XL dual inhibitor that induces Bax-dependent apoptosis

New treatment options, such as targeted therapies, are urgently needed for the treatment of colorectal cancer (CRC), the third leading cause of cancer-related deaths worldwide. The current study focuses on demonstrating the therapeutic efficacies of APG-1252-M1 (an active form of the prodrug, APG-1252 or pelcitoclax), a highly potent Bcl-2/Bcl-XL dual inhibitor in clinical trials, against CRC and understanding the underlying mechanisms. APG-1252-M1 effectively decreased the survival of CRC cell lines, particularly those expressing relatively low levels of Mcl-1, with the induction of apoptosis. High levels of Mcl-1 were significantly correlated with decreased sensitivity of CRC cell lines to APG-1252-M1. When combined with an Mcl-1 inhibitor, APG-1252-M1 synergistically decreased the survival and induced apoptosis of APG-1252-M1-insensitive cell lines with high levels of Mcl-1. This combination further decreased the survival and enhanced apoptosis even in sensitive cell lines with relatively low levels of Mcl-1, whereas enforced expression of ectopic Mcl-1 in these cells abrogated APG-1252-M1's effects on decreasing cell survival and inducing apoptosis, which could be reversed by Mcl-1 inhibition. APG-1252-M1 rapidly induced cytochrome C and Smac release from mitochondria with caspase-3 and PARP cleavage. Deficiency of Bax in CRC cells abolished APG-1252-M1's ability to induce apoptosis, indicating that APG-1252-M1 induces Bax-dependent apoptosis. The current study thus demonstrates the potential of APG-1252-M1 as a monotherapy in the treatment of CRC, particularly those with low Mcl-1 expression, or in combination with an Mcl-1 inhibitor, warranting further evaluation in vivo and in the clinic.

Effects of clinical and metabolic variables and hormones on the expression of immune protein biomarkers in the endometrium of women with polycystic ovary syndrome and normal-cycling controls

BACKGROUND

Women with polycystic ovary syndrome (PCOS) are at an elevated risk of endometrial cancer, which may be associated with the continuous proliferative state caused by the interaction between hormones and metabolic factors.

OBJECTIVE

To investigate the impact of hormones and metabolic factors in the proliferation and death of endometrium during the proliferative phase.

METHODS

Cross-sectional study with 11 women with PCOS and eight normal-cycling non-PCOS controls at the Federal University of the State of Rio de Janeiro from February 2011 to June 2019. Clinical, biochemical, and hormonal data were collected to analyze their influence on the expression of biomarkers related to the endometrial tissue breakdown. Hysteroscopy and endometrial biopsies were conducted, and the endometrial samples underwent immunohistochemistry for markers of apoptosis B-cell lymphoma 2 (BCL2), cleaved caspase-3 (CASP3), fas cell surface death receptor (FAS), FAS ligand (FASLG), BCL2 associated X (BAX), marker of proliferation Ki-67 (MKI67), and cell death using terminal deoxynucleotidyl transferase dUTP nick and labeling (TUNEL).

RESULTS

CASP3 and TUNEL expressions were lower in both stroma and endometrium gland of PCOS women than in controls. MKI67 and homeostasis indexes (BCL2/BAX; FASLG/FAS) in the endometrium of the PCOS group were significantly higher. Body mass index (BMI) values were positively correlated with the expression of MKI67 and MKI67/TUNEL ratio in the endometrial stroma compartment. Fasting insulin levels were positively correlated with the expression of BCL2, and DHEA-S levels were negatively correlated with the expression of CASP3 of women with PCOS.

CONCLUSION

BMI, insulin, and DHEA-S influence the endometrial homeostasis breakdown in PCOS in the endometrium stroma.

Morpholine substituted quinazoline derivatives as anticancer agents against MCF-7, A549 and SHSY-5Y cancer cell lines and mechanistic studies

A series of morpholine substituted quinazoline derivatives have been synthesized and evaluated for cytotoxic potential against A549, MCF-7 and SHSY-5Y cancer cell lines. These compounds were found to be non-toxic against HEK293 cells at 25 μM and hence display anticancer potential. In these series compounds, AK-3 and AK-10 displayed significant cytotoxic activity against all the three cell lines. AK-3 displayed IC50 values of 10.38 ± 0.27 μM, 6.44 ± 0.29 μM and 9.54 ± 0.15 μM against A549, MCF-7 and SHSY-5Y cancer cell lines. Similarly, AK-10 showed IC50 values of 8.55 ± 0.67 μM, 3.15 ± 0.23 μM and 3.36 ± 0.29 μM against A549, MCF-7 and SHSY-5Y, respectively. In the mechanistic studies, it was found that AK-3 and AK-10 inhibit the cell proliferation in the G1 phase of the cell cycle and the primary cause of death of the cells was found to be through apoptosis. Thus, morpholine based quinazoline derivatives have the potential to be developed as potent anticancer drug molecules.

Specific Local Predictors That Reflect the Tropism of Endometriosis-A Multiple Immunohistochemistry Technique

Ectopic endometrial epithelium associates a wide spectrum of symptomatology. Their evolution can be influenced by inflammatory and vascular changes, that affect not only the structure and cell proliferation rate, but also symptoms. This prospective study involved tissue samples from surgically treated patients, stained using classical histotechniques and immunohistochemistry. We assessed ectopic endometrial glands (CK7+, CK20-), adjacent blood vessels (CD34+), estrogen/progesterone hormone receptors (ER+, PR+), inflammatory cells (CD3+, CD20+, CD68+, Tryptase+), rate of inflammatory cells (Ki67+) and oncoproteins (BCL2+, PTEN+, p53+) involved in the development of endometriosis/adenomyosis. A CK7+/CK20- expression profile was present in the ectopic epithelium and differentiated it from digestive metastases. ER+/PR+ were present in all cases analyzed. We found an increased vascularity (CD34+) in the areas with abdominal endometriosis and CD3+-:T-lymphocytes, CD20+-:B-lymphocytes, CD68+:macrophages, and Tryptase+: mastocytes were abundant, especially in cases with adenomyosis as a marker of proinflammatory microenvironment. In addition, we found a significantly higher division index-(Ki67+) in the areas with adenomyosis, and inactivation of tumor suppressor genes-p53+ in areas with neoplastic changes. The inflammatory/vascular/hormonal mechanisms trigger endometriosis progression and neoplastic changes increasing local pain. Furthermore, they may represent future therapeutic targets. Simultaneous-multiple immunohistochemical labelling represents a valuable technique for rapidly detecting cellular features that facilitate comparative analysis of the studied predictors.

Neutralizing Anti-IL-17A Antibody Demonstrates Preclinical Activity Enhanced by Vinblastine in Langerhans Cell Histiocytosis

Langerhans cell histiocytosis (LCH) is an inflammatory myeloid neoplasm characterised by the accumulation into granulomas of apoptosis-resistant pathological dendritic cells (LCH-DCs). LCH outcome ranges from self-resolving to fatal. Having previously shown that, (i) monocyte-derived DCs (Mo-DCs) from LCH patients differentiate into abnormal and pro-inflammatory IL-17A-producing DCs, and (ii) recombinant IL-17A induces survival and chemoresistance of healthy Mo-DCs, we investigated the link between IL-17A and resistance to apoptosis of LCH-DCs. In LCH granulomas, we uncovered the strong expression of BCL2A1 (alias BFL1), an anti-apoptotic BCL2 family member. In vitro, intracellular IL-17A expression was correlated with BCL2A1 expression and survival of Mo-DCs from LCH patients. Based on the chemotherapeutic drugs routinely used as first or second line LCH therapy, we treated these cells with vinblastine, or cytarabine and cladribine. Our preclinical results indicate that high doses of these drugs decreased the expression of Mcl-1, the main anti-apoptotic BCL2 family member for myeloid cells, and killed Mo-DCs from LCH patients ex vivo, without affecting BCL2A1 expression. Conversely, neutralizing anti-IL-17A antibodies decreased BCL2A1 expression, the downregulation of which lowered the survival rate of Mo-DCs from LCH patients. Interestingly, the in vitro combination of low-dose vinblastine with neutralizing anti-IL-17A antibodies killed Mo-DCs from LCH patients. In conclusion, we show that BCL2A1 expression induced by IL-17A links the inflammatory environment to the unusual pro-survival gene activation in LCH-DCs. Finally, these preclinical data support that targeting both Mcl-1 and BCL2A1 with low-dose vinblastine and anti-IL-17A biotherapy may represent a synergistic combination for managing recurrent or severe forms of LCH.

New Bioactive Fused Triazolothiadiazoles as Bcl-2-Targeted Anticancer Agents

A series of 3-(6-substituted phenyl-[1,2,4]-triazolo[3,4-b]-[1,3,4]-thiadiazol-3-yl)-1H-indoles (5a–l) were designed, synthesized and evaluated for anti-apoptotic Bcl-2-inhibitory activity. Synthesis of the target compounds was readily accomplished through a reaction of acyl hydrazide (1) with carbon disulfide in the presence of alcoholic potassium hydroxide to afford the corresponding intermediate potassium thiocarbamate salt (2), which underwent cyclization reaction in the presence of excess hydrazine hydrate to the corresponding triazole thiol (3). Further cyclisation reaction with substituted benzoyl chloride derivatives in the presence of phosphorous oxychloride afforded the final 6-phenyl-indol-3-yl [1,2,4]-triazolo[3,4-b]-[1,3,4]-thiadiazole compounds (5a–l). The novel series showed selective sub-micromolar IC₅₀ growth-inhibitory activity against Bcl-2-expressing human cancer cell lines. The most potent 6-(2,4-dimethoxyphenyl) substituted analogue (5k) showed selective IC₅₀ values of 0.31–0.7 µM against Bcl-2-expressing cell lines without inhibiting the Bcl-2-negative cell line (Jurkat). ELISA binding affinity assay (interruption of Bcl-2-Bim interaction) showed potent binding affinity for (5k) with an IC₅₀ value of 0.32 µM. Moreover, it fulfils drug likeness criteria as a promising drug candidate.

BH3-mimetics: recent developments in cancer therapy

The hopeful outcomes from 30 years of research in BH3-mimetics have indeed served a number of solid paradigms for targeting intermediates from the apoptosis pathway in a variety of diseased states. Not only have such rational approaches in drug design yielded several key therapeutics, such outputs have also offered insights into the integrated mechanistic aspects of basic and clinical research at the genetics level for the future. In no other area of medical research have the effects of such work been felt, than in cancer research, through targeting the BAX-Bcl-2 protein-protein interactions. With these promising outputs in mind, several mimetics, and their potential therapeutic applications, have also been developed for several other pathological conditions, such as cardiovascular disease and tissue fibrosis, thus highlighting the universal importance of the intrinsic arm of the apoptosis pathway and its input to general tissue homeostasis. Considering such recent developments, and in a field that has generated so much scientific interest, we take stock of how the broadening area of BH3-mimetics has developed and diversified, with a focus on their uses in single and combined cancer treatment regimens and recently explored therapeutic delivery methods that may aid the development of future therapeutics of this nature.

Antisense Oligonucleotide-Mediated Splice Switching: Potential Therapeutic Approach for Cancer Mitigation

Splicing is an essential process wherein precursor messenger RNA (pre-mRNA) is reshaped into mature mRNA. In alternative splicing, exons of any pre-mRNA get rearranged to form mRNA variants and subsequently protein isoforms, which are distinct both by structure and function. On the other hand, aberrant splicing is the cause of many disorders, including cancer. In the past few decades, developments in the understanding of the underlying biological basis for cancer progression and therapeutic resistance have identified many oncogenes as well as carcinogenic splice variants of essential genes. These transcripts are involved in various cellular processes, such as apoptosis, cell signaling and proliferation. Strategies to inhibit these carcinogenic isoforms at the mRNA level are promising. Antisense oligonucleotides (AOs) have been developed to inhibit the production of alternatively spliced carcinogenic isoforms through splice modulation or mRNA degradation. AOs can also be used to induce splice switching, where the expression of an oncogenic protein can be inhibited by the induction of a premature stop codon. In general, AOs are modified chemically to increase their stability and binding affinity. One of the major concerns with AOs is efficient delivery. Strategies for the delivery of AOs are constantly being evolved to facilitate the entry of AOs into cells. In this review, the different chemical modifications employed and delivery strategies applied are discussed. In addition to that various AOs in clinical trials and their efficacy are discussed herein with a focus on six distinct studies that use AO-mediated exon skipping as a therapeutic strategy to combat cancer.

Low-doses of aspirin promote the growth of human PC-9 lung cancer cells through activation of the MAPK family

Aspirin has been reported for its anti-tumor activity, however, there are few studies on its effects in lung cancer. The present study found that aspirin had a dual role in the proliferation of human lung cancer PC-9 (formerly known as PC-14) and A549 cells, and in human colon cancer HCT116 cells. The cells were treated with 0, 1, 2, 4, 8 and 16 mM aspirin for 24-72 h or 7-12 days and cell proliferation was examined by MTT and colony formation assay. In order to explore the relationship between the proliferation-enhancing effect of low-dose aspirin and mitogen-activated protein kinase (MAPK) signaling activation, PC-9 cells were pretreated with 10 µM PD98059 (a specific inhibitor of ERK), SB203580 (a specific inhibitor of p38) and SP600125 (a specific inhibitor of JNK) for 30 min respectively. Western blot assay was performed to detect the activation of MAPK members in PC-9 cells. Cellular apoptosis was detected using flow cytometer-based Annexin V/propidium iodide dual staining. An assessment of MAPK inhibitors was performed to further validate the role of JNK, p38 and ERK in aspirin-promoted PC-9 cell growth. It was demonstrated that aspirin could promote the growth of human PC-9 lung cancer cells and induced MAPK activation at low concentrations. All the MAPK inhibitors tested (PD98059, SB203580 and SP600125) were able to inhibit the aspirin-induced proliferation of PC-9 cells.

Ligand-based design approach of potential Bcl-2 inhibitors for cancer chemotherapy

BACKGROUND AND OBJECTIVES

Overexpression of prosurvival Bcl-2 family members make tumor cells resistant to conventional cancer therapeutic agents. It is commonly observed feature in many different types of human tumors. Hence, small-molecules as Bcl-2 inhibitors may have a promising therapeutic potential for the treatment of human cancer. The given study focusses on development of novel and small Bcl-2 inhibitors using ligand-based drug design approach.

METHODS

Ligand based pharmacophore was generated using the PHASE tool of Schrödinger and screened ZINC database through ZINCPharmer webserver to identify compounds with similar features. Compounds having good fitness score were selected for molecular docking and binding interactions were compared with drugs in market as well as trials. QSAR model was generated using advanced AutoQSAR tool and validated for prediction of unknown compounds. QSAR prediction of in silico active identified three potential compounds and were subjected to investigate stability by molecular dynamics simulations and MM-PBSA binding energy calculations.

RESULTS

Study identified three in silico potential molecules with good stability and binding affinity. Further substructure search and pIC₅₀ value prediction has identified six more molecules. Total nine molecules have demonstrated good drug likeness features.

CONCLUSION

Final oral rat LD50 calculation of nine molecules has identified three hit molecules i.e., ZINC76760927, ZINC76768675 and ZINC52767796 for further in vitro and in vivo testing as safe and potential Bcl-2 inhibitors.

Combination Therapy of Navitoclax with Chemotherapeutic Agents in Solid Tumors and Blood Cancer: A Review of Current Evidence

Combination therapy emerges as a fundamental scheme in cancer. Many targeted therapeutic agents are developed to be used with chemotherapy or radiation therapy to enhance drug efficacy and reduce toxicity effects. ABT-263, known as navitoclax, mimics the BH3-only proteins of the BCL-2 family and has a high affinity towards pro-survival BCL-2 family proteins (i.e., BCL-XL, BCL-2, BCL-W) to induce cell apoptosis effectively. A single navitoclax action potently ameliorates several tumor progressions, including blood and bone marrow cancer, as well as small cell lung carcinoma. Not only that, but navitoclax alone also therapeutically affects fibrotic disease. Nevertheless, outcomes from the clinical trial of a single navitoclax agent in patients with advanced and relapsed small cell lung cancer demonstrated a limited anti-cancer activity. This brings accumulating evidence of navitoclax to be used concomitantly with other chemotherapeutic agents in several solid and non-solid tumors that are therapeutically benefiting from navitoclax treatment in preclinical studies. Initially, we justify the anti-cancer role of navitoclax in combination therapy. Then, we evaluate the current evidence of navitoclax in combination with the chemotherapeutic agents comprehensively to indicate the primary regulator of this combination strategy in order to produce a therapeutic effect.

Senescent cells in cancer therapy: why and how to remove them

Cellular senescence is a stress response that imposes a growth arrest on cancer and nonmalignant cells during cancer therapy. By secreting a plethora of proinflammatory factors collectively termed the senescence-associated secretory phenotype (SASP), therapy-induced senescent cells can promote tumorigenesis. Moreover, the SASP from senescent cells is also able to drive therapy resistance and mediate many adverse effects of cancer therapy. Because senescent cell production often occurs during cancer therapy, it is important to carefully consider these potential detrimental effects. Senotherapy, which refers to selective removal of senescent cells, has been proposed as a promising adjuvant approach to eliminate the adverse effects of senescent cells. Thus, in this review we summarize in detail the mechanisms by which senescent cells contribute to tumorigenesis and therapeutic resistance. Also, we thoroughly discuss the potential strategies regarding how to effectively circumvent the undesirable effects of therapy-induced senescent cells.

Effects of jasplakinolide on cytotoxicity, cytoskeleton and apoptosis in two different colon cancer cell lines treated with m-THPC-PDT

Colorectal cancer (CRC) is a common malignant tumor, and metastasis is one of the most important challenges in the treatment of CRC. Photodynamic therapy (PDT) is a novel and non-invasive treatment that influence cytoskeleton and to reduce cancer metastases. In addition, cytoskeleton is related to cancer metastases. Two isogenic colorectal cancer cell lines SW480 and SW620 were used in the present study, we found that m-THPC mediated PDT changed the cytotoxicity, apoptosis and cytoskeleton in both cell lines. Interestingly, the expression of intermediate filaments protein cytokeratin18 were different in the two cell lines. In order to further confirm the relationship between cytoskeleton and cell migration, we combined with microfilament stabilizer jasplakinolide (JASP) to observe the effects of microfilaments on cell migration, cytotoxicity and apoptosis. Taken together, these findings suggest that m-THPC-PDT could induce cytoplasmic cytoskeleton destruction in both types of cells, especially on microfilaments and microtubules. Moreover, in SW480 cells, microtubules may participate in the apoptosis process induced by m-THPC-PDT, while microfilaments may participate in the process of m-THPC-PDT inhibiting cell migration. But in SW620 cells, only microfilaments may be involved in m-THPC-PDT induced apoptosis and inhibition of cell migration.

Targeted Therapies in Lung Cancers: Current Landscape and Future Prospects

BACKGROUND

Lung cancer is the most common and malignant cancer worldwide. Targeted therapies have emerged as a promising treatment strategy for lung cancers.

OBJECTIVE

The objective of this study is to evaluate the current landscape of targets and finding promising targets for future new drug discovery for lung cancers by identifying the science-technology-clinical development pattern and mapping the interaction network of targets.

METHODS

Targets for cancers were classified into 3 groups based on a paper published in Nature. We search for scientific literature, patent documents and clinical trials of targets in Group 1 and Group 2 for lung cancers. Then, a target-target interaction network of Group 1 was constructed, and the science-technology-clinical(S-T-C) development patterns of targets in Group 1 were identified. Finally, based on the cluster distribution and the development pattern of targets in Group 1, interactions between the targets were employed to predict potential targets in Group 2 on drug development.

RESULTS

The target-target interaction(TTI)network of group 1 resulted in 3 clusters with different developmental stages. The potential targets in Group 2 are divided into 3 ranks. Level-1 is the first priority and level-3 is the last. Level-1 includes 16 targets, such as STAT3, CRKL, and PTPN11, that are mostly involved in signaling transduction pathways. Level-2 and level-3 contain 8 and 6 targets related to various biological functions.

CONCLUSION

This study will provide references for drug development in lung cancers, emphasizing that priorities should be given to targets in Level-1, whose mechanisms are worth further exploration.

Structure-based design approach of potential BCL-2 inhibitors for cancer chemotherapy

B-cell lymphoma 2 (BCL-2) family is one of the chief regulators of cellular apoptosis. The intricate interactions between pro-apoptotic and anti-apoptotic genes of the BCL-2 family dictate the apoptotic balance of the cell. An overexpression of the anti-apoptotic members of BCL-2 is indicative of cell death evasion and cancer metastasis. Among the four BCL-2 homology domains, the BH3 domain plays a key role in the suppression of BCL-2 expression. Therefore, BH3-mimetic drugs are currently investigated for their suitability as BCL-2 inhibitors. In the present study, we followed a structure-based pharmacophore modelling approach to identify BH3-mimetic small molecules, to formulate a more precise and targeted cancer treatment regimen. To identify proteins with similar binding features, a structure-based pharmacophore model was generated based on the structure of Bcl-2 complexed with Venetoclax (PDB-ID:6O0K). Compounds with good fitness score and pharmacophore features, screened from the ZINC database, were subjected to (i) molecular docking studies, (ii) molecular mechanics-generalized Born surface area (MM-GBSA), and (iii) absorption, distribution, metabolism, excretion and toxicity (ADMET) prediction. From the analysis, two molecules were identified: ZINC68728276 and ZINC14166367, with docking scores of -7.323 and -8.649 kcal/mol and free binding energies (MM-GBSA) of -72.913 and -72.291 kcal/mol, respectively. The structural parameters and binding affinity of these complexes were validated through molecular dynamics simulation and molecular mechanics-Poisson-Boltzmann surface area (MM-PBSA) free energy calculations and compared with Venetoclax. The results indicated stability and good binding affinity of both the compounds. The study identified ZINC68728276 and ZINC14166367 as in silico potential Bcl-2 inhibitors, which can be further considered for in vitro studies.

miR-140-3p inhibits colorectal cancer progression and its liver metastasis by targeting BCL9 and BCL2

Recent studies have identified microRNAs (miRNAs) as a compelling novel class of biomarker in colorectal cancer (CRC) development and metastasis. Here, we demonstrated that the level of plasma exosomal miR‐140‐3p in CRC patients was lower than that in healthy controls. The decreased miR‐140‐3p level was also observed in CRC patients with liver metastasis. The expression of miR‐140‐3p in CRC tissues were significantly lower than that in matched normal tissues. Functionally, miR‐140‐3p overexpression suppressed proliferation, migration, invasion, and β‐catenin nuclear translocation, as well as promoted apoptosis in LoVo cells, while inhibition of miR‐140‐3p reversed these cellular processes in HCT 116 cells. Notably, BCL9 and BCL2 were recognized as direct targets of miR‐140‐3p. BCL9 knockdown abrogated miR‐140‐3p inhibitor‐induced effects on HCT 116 cells with decreased proliferation, migration, and invasion. BCL2 knockdown increased apoptosis of miR‐140‐3p inhibitor‐transfected HCT 116 cells. In vivo experiments revealed that miR‐140‐3p overexpression inhibited tumor growth in LoVo xenograft model and diminished metastatic nodules in nude mice liver. Taken together, this work supports that miR‐140‐3p exerts as a tumor suppressor in CRC progression via targeting BCL9 and BCL2, and suggests miR‐140‐3p‐BCL9/BCL2 axis may be applied in miRNA‐based therapy and prognostication of CRC.

Challenges and Advances in Managing Thrombocytopenic Cancer Patients

Cancer patients have varying incidence, depth and duration of thrombocytopenia. The mainstay of managing severe chemotherapy-induced thrombocytopenia (CIT) in cancer is the use of platelet transfusions. While prophylactic platelet transfusions reduce the bleeding rate, multiple unmet needs remain, such as high residual rates of bleeding, and anticancer treatment dose reductions/delays. Accordingly, the following promising results in other settings, antifibrinolytic drugs have been evaluated for prevention and treatment of bleeding in patients with hematological malignancies and solid tumors. In addition, Thrombopoeitin receptor agonists have been studied for two major implications in cancer: treatment of severe thrombocytopenia associated with myelodysplastic syndrome and acute myeloid leukemia; primary and secondary prevention of CIT in solid tumors in order to maintain dose density and intensity of anti-cancer treatment. Furthermore, thrombocytopenic cancer patients are often prescribed antithrombotic medication for indications arising prior or post cancer diagnosis. Balancing the bleeding and thrombotic risks in such patients represents a unique clinical challenge. This review focuses upon non-transfusion-based approaches to managing thrombocytopenia and the associated bleeding risk in cancer, and also addresses the management of antithrombotic therapy in thrombocytopenic cancer patients.

Senolytics for Cancer Therapy: Is All That Glitters Really Gold?

Simple Summary

Senescence is an essential component of tumor cell biology and is a primary cell stress response to therapy. While the long-term impact of senescence in cancer therapy is not yet fully understood, the use of senolytics, drugs that selectively kill senescent cells, is an area of active investigation in cancer treatment. Several challenges and unanswered questions have arisen from the current preclinical literature, indicating the need to re-evaluate some of the basic premises and experimental approaches, as well as the potential utility for translating to the clinic the application of senolytics as adjuvants to current cancer therapy.

Abstract

Senolytics represent a group of mechanistically diverse drugs that can eliminate senescent cells, both in tumors and in several aging-related pathologies. Consequently, senolytic use has been proposed as a potential adjuvant approach to improve the response to senescence-inducing conventional and targeted cancer therapies. Despite the unequivocal promise of senolytics, issues of universality, selectivity, resistance, and toxicity remain to be further clarified. In this review, we attempt to summarize and analyze the current preclinical literature involving the use of senolytics in senescent tumor cell models, and to propose tenable solutions and future directions to improve the understanding and use of this novel class of drugs.

Palbociclib Renders Human Papilloma Virus-Negative Head and Neck Squamous Cell Carcinoma Vulnerable to the Senolytic Agent Navitoclax

We demonstrate that inhibition of cyclin-dependent kinases 4/6 (CDK4/6) leads to senescence in human papillomavirus (HPV)-negative (-) head and neck squamous cell carcinoma (HNSCC), but not in HPV-positive (+) HNSCC. The BCL-2 family inhibitor, navitoclax, has been shown to eliminate senescent cells effectively. We evaluated the efficacy of combining palbociclib and navitoclax in HPV^- HNSCC. Three HPV^- HNSCC cell lines (CAL27, HN31, and PCI15B) and three HPV⁺ HNSCC cell lines (UPCI-SCC-090, UPCI-SCC-154, and UM-SCC-47) were treated with palbociclib. Treatment drove reduced expression of phosphorylated Rb (p-Rb) and phenotypic evidence of senescence in all HPV^- cell lines, whereas HPV⁺ cell lines did not display a consistent response by Rb or p-Rb and did not exhibit morphologic changes of senescence in response to palbociclib. In addition, treatment of HPV^- cells with palbociclib increased both β-galactosidase protein expression and BCL-xL protein expression compared with untreated controls in HPV^- cells. Co-expression of β-galactosidase and BCL-xL occurred consistently, indicating elevated BCL-xL expression in senescent cells. Combining palbociclib with navitoclax led to decreased HPV^- HNSCC cell survival and led to increased apoptosis levels in HPV^- cell lines compared with each agent given alone. IMPLICATIONS: This work exploits a key genomic hallmark of HPV^- HNSCC (CDKN2A disruption) using palbociclib to induce BCL-xL-dependent senescence, which subsequently causes the cancer cells to be vulnerable to the senolytic agent, navitoclax.

Nicotinamide adenine dinucleotide phosphate oxidase inhibitor induces apoptosis on Epstein-Barr virus positive B lymphoma cells

Over-expression of nicotinamide adenine dinucleotide phosphate oxidase (Nox) isoform enzymes was recently reported in various cancers including Burkitt’s lymphoma (BL). However, the functions of Nox isoform enzymes in BL remain poorly understood. In this study, Nox isoform expression and the effects of a Nox-specific inhibitor were evaluated in Epstein-Barr virus (EBV)-positive Raji BL cells in comparison with EBV-negative Ramos BL cells. To evaluate Nox enzyme expression in Raji and Ramos BL cells, polymerase chain reaction (PCR) and western blot analysis were performed. To verify the intracellular signaling mechanism of the Nox inhibitor-induced apoptosis of Raji cells, WST-1 assay, trypan blue exclusion method, flow cytometry, PCR, western blotting, and bromodeoxyuridine staining were conducted. Experiments using the pan-caspase inhibitor z-VAD, reactive oxygen species scavenger N-acetyl-L-cysteine (NAC), and Bim inhibitor 1 were performed. PCR and western blot results showed that Nox isoform enzymes were highly expressed in EBV-positive BL Raji cells compared with EBV-negative BL Ramos cells. The Nox2 inhibitor induced apoptosis of Raji cells in time- and dose-dependent manners. The Nox2 inhibitor also caused up-regulation of Bim and Noxa, down-regulation of Mcl-1, translocation of Bax, release of cytochrome c, and caspase cascade activation, resulting in apoptosis. Furthermore, z-VAD, NAC, and BI-1 effectively blocked the Nox2 inhibitor-induced apoptosis of Raji cells. Taken together, these results provide a novel insight into the mechanism of Nox inhibitor-induced apoptosis and evidence for Nox as a therapeutic target to treat EBV-positive malignancies.

Inflammation driven tumor-like signaling in prostatic epithelial cells by sexually transmitted Trichomonas vaginalis

OBJECTIVES

To identify the sequence of inflammation-driven signaling cascades and other molecular events that might cause tumor-like transformation of prostatic cells.

METHODS

Cytokine array analysis, Reactome and STRING analysis, immunoblotting, and immunocytochemistry were used to investigate the molecular mechanisms governing inflammation-driven adverse changes in human prostatic cells caused by the sexually transmitted infection, Trichomonas vaginalis, resulting in prostatitis, benign prostatic hyperplasia and prostate cancer.

RESULTS

Array analysis showed upregulation of 23 cytokines within 24 h of infection of human prostatic epithelial RWPE-1 cells with the parasite, in vitro. Reactome and STRING analysis of array data identified interleukin-6, interleukin-8, nuclear factor kappa B, signal transducer and activator of transcription 3 and cyclooxygenase 2 as chief instigators of prostatic anomaly, which were found to be significantly upregulated by immunofluorescence and western blotting analyses. STRING further connected these instigators with macrophage migration inhibitory factor, PIM-1 and prostate-specific antigen; which was confirmed by their marked stimulation in infected prostatic cells by immunoblotting and immunocytochemistry. Upregulated proliferation markers, such as Ki67, proliferating cell nuclear antigen and B-cell lymphoma 2, suggested tumor-like signaling in infected RWPE-1 cells, which was further supported by downregulation of E-cadherin, upregulation of vimentin and activation of focal adhesion kinase. Prostate tumor DU145 cells were more sensitive to parasite invasion, and showed rapid upregulation with nuclear translocation of sensitive parameters, such as nuclear factor kappa B, signal transducer and activator of transcription 3, and macrophage migration inhibitory factor. The migration of DU145 cells augmented when incubated in spent media from parasite-infected RWPE-1 cells.

CONCLUSION

The initiation of inflammation driven tumor-like cell signaling in parasite-infected human prostatic epithelial cells is apparent, with the prostate tumor (DU145) cells being more sensitive to T. vaginalis than normal (RWPE-1) prostatic cells.

Regulation of Cell Death by Mitochondrial Transport Systems of Calcium and Bcl-2 Proteins

Mitochondria represent the fundamental system for cellular energy metabolism, by not only supplying energy in the form of ATP, but also by affecting physiology and cell death via the regulation of calcium homeostasis and the activity of Bcl-2 proteins. A lot of research has recently been devoted to understanding the interplay between Bcl-2 proteins, the regulation of these interactions within the cell, and how these interactions lead to the changes in calcium homeostasis. However, the role of Bcl-2 proteins in the mediation of mitochondrial calcium homeostasis, and therefore the induction of cell death pathways, remain underestimated and are still not well understood. In this review, we first summarize our knowledge about calcium transport systems in mitochondria, which, when miss-regulated, can induce necrosis. We continue by reviewing and analyzing the functions of Bcl-2 proteins in apoptosis. Finally, we link these two regulatory mechanisms together, exploring the interactions between the mitochondrial Ca2+ transport systems and Bcl-2 proteins, both capable of inducing cell death, with the potential to determine the cell death pathway-either the apoptotic or the necrotic one.

Acute toxicity analysis of Disarib, an inhibitor of BCL2

Small molecule inhibitors targeting BCL2 are explored as anticancer therapeutics. Previously, we have reported identification and characterization of a novel BCL2 inhibitor, Disarib. Disarib induced cancer cell death in a BCL2 dependent manner in different cancer cell lines and mouse tumor models when it was administered intraperitoneally. In the present study, using two syngeneic mouse models, breast adenocarcinoma (EAC) and Dalton’s lymphoma (DLA), we show that oral administration of Disarib resulted in significant tumor regression in a concentration dependent manner. Importantly, tumor developed in both female and male mice were equally sensitive to Disarib. Further, we have investigated the toxicity of Disarib in normal cells. Single dose toxicity analysis of Disarib in male and female mice after oral administration revealed no significant variations compared to control group for parameters such as body weight, food and water consumption and behavioural changes which were analysed for the entire period of study. Haematological and histopathological analyses also did not show any significant difference from the control groups. Thus, our results reveal safe use of Disarib as a small molecule inhibitor and provide the foundation for investigation of other preclinical studies.