The p38 MAPK inhibitor BIRB796 enhances the antitumor effects of VX680 in cervical cancer

Amlodipine inhibits Synaptotagmin-4's oncogenic activity on gastric cancer proliferation by targeting calcium signaling

BACKGROUND

Gastric cancer (GC) remains a leading cause of cancer mortality globally. Synaptotagmin-4 (SYT4), a calcium-sensing synaptic vesicle protein, has been implicated in the oncogenesis of diverse malignancies.

PURPOSE

This study delineates the role of SYT4 in modulating clinical outcomes and biological behaviors in GC.

METHODS

We evaluated SYT4 expression in GC specimens using bioinformatics analyses and immunohistochemistry. Functional assays included CCK8 proliferation tests, apoptosis assays via flow cytometry, confocal calcium imaging, and xenograft models. Western blotting elucidated MAPK pathway involvement. Additionally, we investigated the impact of the calcium channel blocker amlodipine on cellular dynamics and MAPK pathway activity.

RESULTS

SYT4 was higher in GC tissues, and the elevated SYT4 was significantly correlated with adverse prognosis. Both univariate and multivariate analyses confirmed SYT4 as an independent prognostic indicator for GC. Functionally, SYT4 promoted tumorigenesis by fostering cellular proliferation, inhibiting apoptosis, and enhancing intracellular Ca2+ influx, predominantly via MAPK pathway activation. Amlodipine pre-treatment attenuated SYT4-driven cell growth and potentiated apoptosis, corroborated by in vivo xenograft assessments. These effects were attributed to MAPK pathway suppression by amlodipine.

CONCLUSION

SYT4 emerges as a potential prognostic biomarker and a pro-oncogenic mediator in GC through a Ca2+-dependent MAPK mechanism. Amlodipine demonstrates significant antitumor effects against SYT4-driven GC, positing its therapeutic promise. This study underscores the imperative of targeting calcium signaling in GC treatment strategies.

Centrosomes and associated proteins in pathogenesis and treatment of breast cancer

Breast cancer is the most prevalent malignancy among women worldwide. Despite significant advances in treatment, it remains one of the leading causes of female mortality. The inability to effectively treat advanced and/or treatment-resistant breast cancer demonstrates the need to develop novel treatment strategies and targeted therapies. Centrosomes and their associated proteins have been shown to play key roles in the pathogenesis of breast cancer and thus represent promising targets for drug and biomarker development. Centrosomes are fundamental cellular structures in the mammalian cell that are responsible for error-free execution of cell division. Centrosome amplification and aberrant expression of its associated proteins such as Polo-like kinases (PLKs), Aurora kinases (AURKs) and Cyclin-dependent kinases (CDKs) have been observed in various cancers, including breast cancer. These aberrations in breast cancer are thought to cause improper chromosomal segregation during mitosis, leading to chromosomal instability and uncontrolled cell division, allowing cancer cells to acquire new genetic changes that result in evasion of cell death and the promotion of tumor formation. Various chemical compounds developed against PLKs and AURKs have shown meaningful antitumorigenic effects in breast cancer cells in vitro and in vivo. The mechanism of action of these inhibitors is likely related to exacerbation of numerical genomic instability, such as aneuploidy or polyploidy. Furthermore, growing evidence demonstrates enhanced antitumorigenic effects when inhibitors specific to centrosome-associated proteins are used in combination with either radiation or chemotherapy drugs in breast cancer. This review focuses on the current knowledge regarding the roles of centrosome and centrosome-associated proteins in breast cancer pathogenesis and their utility as novel targets for breast cancer treatment.

Targeting SMAD-Dependent Signaling: Considerations in Epithelial and Mesenchymal Solid Tumors

SMADs are the canonical intracellular effector proteins of the TGF-β (transforming growth factor-β). SMADs translocate from plasma membrane receptors to the nucleus regulated by many SMAD-interacting proteins through phosphorylation and other post-translational modifications that govern their nucleocytoplasmic shuttling and subsequent transcriptional activity. The signaling pathway of TGF-β/SMAD exhibits both tumor-suppressing and tumor-promoting phenotypes in epithelial-derived solid tumors. Collectively, the pleiotropic nature of TGF-β/SMAD signaling presents significant challenges for the development of effective cancer therapies. Here, we review preclinical studies that evaluate the efficacy of inhibitors targeting major SMAD-regulating and/or -interacting proteins, particularly enzymes that may play important roles in epithelial or mesenchymal compartments within solid tumors.

The effects of HPV oncoproteins on host communication networks: Therapeutic connotations

Human papillomavirus (HPV) infections are a leading cause of viral-induced malignancies worldwide, with a prominent association with cervical and head and neck cancers. The pivotal role of HPV oncoproteins, E5, E6, and E7, in manipulating cellular events, which contribute to viral pathogenesis in various ways, has been extensively documented. This article reviews the influence of HPV oncoproteins on cellular signaling pathways within the host cell, shedding light on the underlying molecular mechanisms. A comprehensive understanding of these molecular alterations is essential for the development of targeted therapies and strategies to combat HPV-induced premalignancies and prevent their progress to cancer. Furthermore, this review underscores the intricate interplay between HPV oncoproteins and some of the most important cellular signaling pathways: Notch, Wnt/β-catenin, MAPK, JAK/STAT, and PI3K AKT/mTOR. The treatment efficacies of the currently available inhibitors on these pathways in an HPV-positive context are also discussed. This review also highlights the importance of continued research to advance our knowledge and enhance therapeutic interventions for HPV-associated diseases.

Small molecule targeting of the p38/Mk2 stress signaling pathways to improve cancer treatment

PURPOSE

Although a long-term goal of cancer therapy always has been the development of agents that selectively destroy cancer cells, more recent trends have been to seek secondary agents that sensitize cancer cells to existing treatment regimens. In this regard, the present study explored the possibility of using small molecule inhibitors of p38MAPK/MK2 stress signaling pathways as potential agents to enhance the sensitivity of cancer cells with abrogated G1 checkpoint to the DNA damaging agent etoposide by specifically targeting the DNA damage-induced G2 cell cycle checkpoint.

METHODS

We have applied CCK8 and FACS-based viability assays and cell cycle analysis to investigate the effect of small molecules SB203580 and MK2.III on the sensitivity of small cell lung cancer cells (SCLC) that lack the G1 checkpoint to the DNA damaging agent Etoposide when used in combination. We have also assessed the effectiveness of combination chemotherapy on tumor xenograft suppression with etoposide and MK2.III in immunosuppressed mice. In addition, additional CCK8 cell viability analysis of the MDA-MB-231 breast cancer cell line, and SW620, and SW480 colorectal cancer cell lines was performed.

RESULTS

Results suggest that etoposide produces a profound effect on the cell cycle profile of cells in a manner that is consistent with the degree of cell viability that is seen using the viable cell assay. Results of the co-treatment experiments revealed that the p38/MK2 kinase inhibitors SB203580 and MK2.III both enhanced the DNA-damaging effects of etoposide on NCI-H69 cell viability in vitro. Results revealed that in vivo MK2.III was able to act as a chemosensitizer when used in combination with etoposide making NCI-H69 lung cancer cells sensitive to chemotherapeutic drug by 45% compared to single usage of the drug. We also report that MK2.III sensitizes metastatic cell lines SW-620 and MDA-MB-231 to etoposide but does not increase the sensitivity of non-metastasizing SW-480 colorectal cells to DNA damaging agent in vitro.

CONCLUSION

Findings reported in this study provide evidence that specific inhibitors of MK2 may indeed improve overall cancer therapy; however, their effectiveness depends on cell types.

p38γ MAPK Inflammatory and Metabolic Signaling in Physiology and Disease

p38γ MAPK (also called ERK6 or SAPK3) is a family member of stress-activated MAPKs and has common and specific roles as compared to other p38 proteins in signal transduction. Recent studies showed that, in addition to inflammation, p38γ metabolic signaling is involved in physiological exercise and in pathogenesis of cancer, diabetes, and Alzheimer's disease, indicating its potential as a therapeutic target. p38γphosphorylates at least 19 substrates through which p38γ activity is further modified to regulate life-important cellular processes such as proliferation, differentiation, cell death, and transformation, thereby impacting biological outcomes of p38γ-driven pathogenesis. P38γ signaling is characterized by its unique reciprocal regulation with its specific phosphatase PTPH1 and by its direct binding to promoter DNAs, leading to transcriptional activation of targets including cancer-like stem cell drivers. This paper will review recent findings about p38γ inflammation and metabolic signaling in physiology and diseases. Moreover, we will discuss the progress in the development of p38γ-specific pharmacological inhibitors for therapeutic intervention in disease prevention and treatment by targeting the p38γ signaling network.

Design and Synthesis of Novel Celastrol Derivatives as Potential Anticancer Agents against Gastric Cancer Cells

Gastric cancer (GC) is a common malignant disease worldwide, and finding novel agents and strategies for the treatment of GC are of urgent need. Celastrol (CEL) is a well-known natural product with antineoplastic activity. In this study, pyrazole analogues were introduced at the C-29 position of CEL. A total of 24 new derivatives were designed, synthesized, and evaluated for their mechanism and antitumor activity in vitro and in vivo. Among them, compound 21 exhibited the best activity against BGC-823 cells (IC₅₀ = 0.21 ± 0.01 μM). Further biological studies showed that 21 significantly raised the reactive oxygen species (ROS) levels to activate the apoptotic pathway, causing mitochondrial dysfunction in BGC-823 cells. In addition, 21 also arrested cells in the G2/M phase to induce tumor cell apoptosis. In a nude mouse tumor xenograft model, 21 exhibited a better tumor inhibition rate (89.85%) than CEL (inhibition rate 76.52%). Taken together, the present study has provided an anticancer lead compound candidate, 21, and has revealed that increased ROS generation may be an effective strategy in the treatment of GC.

Functional Roles of JNK and p38 MAPK Signaling in Nasopharyngeal Carcinoma

c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase (MAPK) family members integrate signals that affect proliferation, differentiation, survival, and migration in a cell context- and cell type-specific way. JNK and p38 MAPK activities are found upregulated in nasopharyngeal carcinoma (NPC). Studies have shown that activation of JNK and p38 MAPK signaling can promote NPC oncogenesis by mechanisms within the cancer cells and interactions with the tumor microenvironment. They regulate multiple transcription activities and contribute to tumor-promoting processes, ranging from cell proliferation to apoptosis, inflammation, metastasis, and angiogenesis. Current literature suggests that JNK and p38 MAPK activation may exert pro-tumorigenic functions in NPC, though the underlying mechanisms are not well documented and have yet to be fully explored. Here, we aim to provide a narrative review of JNK and p38 MAPK pathways in human cancers with a primary focus on NPC. We also discuss the potential therapeutic agents that could be used to target JNK and p38 MAPK signaling in NPC, along with perspectives for future works. We aim to inspire future studies further delineating JNK and p38 MAPK signaling in NPC oncogenesis which might offer important insights for better strategies in diagnosis, prognosis, and treatment decision-making in NPC patients.

Synthesis and in vitro antiproliferative activity of certain novel pyrazolo[3,4-b]pyridines with potential p38α MAPK-inhibitory activity

Novel series of pyrazolo[3,4-b]pyridines 9a-j and 14a-f were prepared via a one-pot three-component reaction. Compounds 9a-j were synthesized by the reaction of 3-(4-chlorophenyl)-1-phenyl-1H-pyrazol-5-amine (4) with benzoyl acetonitriles 3a,b and aldehydes 5a-e, whereas the spiro derivatives 14a-f were synthesized by the reaction of pyrazole derivative 4 with 3a-c and indoline-2,3-diones 10a,b. Screening of the antiproliferative activity of 9a-j and 14a-f revealed that 14a and 14d were the most potent analogues against HepG2 and HeLa cells, with IC₅₀  = 4.2 and 5.9 μM, respectively. Moreover, compounds 9c and 14a could promote cell cycle disturbance and apoptosis in HepG2 cells, as evidenced by DNA flow cytometry and Annexin V-FITC/PI assays. Cell cycle analysis of 9c and 14a indicated a reduction in HepG2 cells in the G1 phase, with arrest in the S phase and the G2/M phase, respectively. Also, 9c and 14a are good apoptotic inducers in the HepG2 cell line. Furthermore, compounds 9h and 14d stood out as the most efficient antiproliferative agents in the NCI 60-cell line panel screening, with mean GI % equal to 60.3% and 55.4%, respectively. Additionally, 9c, 9h, 14a, and 14d showed good inhibitory action against the cellular pathway regulator p38α kinase, with IC₅₀  = 0.42, 0.41, 0.13, and 0.64 μM, respectively. A docking study was carried out on the p38α kinase active site, showing a binding mode comparable to that of reported p38 mitogen-activated protein kinase inhibitors. These newly discovered pyrazolo[3,4-b]pyridines could be considered as potential candidates for the development of newly targeted anticancer agents.

Current Insights of Inhibitors of p38 Mitogen-Activated Protein Kinase in Inflammation

BACKGROUND

The inflammatory process is one of the mechanisms by which our body upholds us from pathogens such as parasites, bacteria, viruses, and other harmful microorganisms. Inflammatory stimuli activate many intracellular signaling pathways such as the nuclear factor-kB (NF-kB) pathway and three mitogen-activated protein kinase (MAPK) pathways, which are mediated through extracellular-signal regulated kinase (ERK), c-Jun N-terminal kinase (JNK) and p38. The p38 has evolved as an enticing target in treating many persistent inflammatory diseases. Hence, designing novel p38 inhibitors targeting MAPK pathways has acquired significance.

OBJECTIVE

Peruse to identify the lead target to discover novel p38MAPK inhibitors with different scaffolds having improved selectivity over the prototype drugs.

METHODS

Structure and the binding sites of p38MAPK were focused. Various scaffolds designed for inhibition and the molecules which have entered the clinical trials are discussed.

RESULTS

This review aspires to present the available information on the structure and the 3D binding sites of p38MAPK, various scaffolds designed for imidazole, urea, benzamide, azoles, quinoxaline, chromone, ketone as a potent p38MAPK inhibitors and their SAR studies and the molecules which have entered the clinical trials.

CONCLUSION

The development of successful selective p38MAPK inhibitors in inflammatory diseases is in progress despite all challenges. It was speculated that p38MAPK also plays an important role in treating diseases such as neuroinflammation, arterial inflammation, vascular inflammation, cancer and so on, which are posing the world with treatment challenges. In this review, clinical trials of drugs are discussed related to inflammatory and its related diseases. Research is in progress to design and develop novel p38MAPK inhibitors with minimal side effects.

An Overview of Novel Agents for Cervical Cancer Treatment by Inducing Apoptosis: Emerging Drugs Ongoing Clinical Trials and Preclinical Studies

As the leading cause of cancer death, cervical cancer ranks fourth for both incidence and mortality. Cervical cancer incidence and mortality rates have reportedly decreased over the last decades thanks to extensive screening and widespread vaccination against human papilloma virus. However, there have been no major improvements concerning platinum-based chemotherapy on the survival of advanced cervical cancer. Thus, novel agents are urgently needed for the improvement of therapeutic effect. With the development of molecular biology and genomics, targeted therapy research has achieved a breakthrough development, including anti-angiogenesis, immune checkpoint inhibitors, and other treatments that are efficient for treatment of cervical cancer. Apoptosis is a crucial process for tumor progression. Drugs directed at inducing tumor-cell apoptosis are regarded as important treatment modalities. Besides, a number of novel compounds synthesized or derived from plants or microorganisms exhibited prominent anti-cancer activity by changing the apoptotic balance in cervical cancer. In this review, we summarized new target therapy drugs ongoing clinical trials that are used for treatment of cervical cancer. Further, we classified novel agents with a focus on improvement of therapeutic effect pre-clinically. To summarize, we also discussed application prospects of the new uses of old drugs and drug combinations, to provide researchers with new ideas for cervical cancer treatment.

Computer-Aided Drug Design Applied to Secondary Metabolites as Anticancer Agents

Computer-Aided Drug Design (CADD) techniques have garnered a great deal of attention in academia and industry because of their great versatility, low costs, possibilities of cost reduction in in vitro screening and in the development of synthetic steps; these techniques are compared with highthroughput screening, in particular for candidate drugs. The secondary metabolism of plants and other organisms provide substantial amounts of new chemical structures, many of which have numerous biological and pharmacological properties for virtually every existing disease, including cancer. In oncology, compounds such as vimblastine, vincristine, taxol, podophyllotoxin, captothecin and cytarabine are examples of how important natural products enhance the cancer-fighting therapeutic arsenal. In this context, this review presents an update of Ligand-Based Drug Design and Structure-Based Drug Design techniques applied to flavonoids, alkaloids and coumarins in the search of new compounds or fragments that can be used in oncology. A systematical search using various databases was performed. The search was limited to articles published in the last 10 years. The great diversity of chemical structures (coumarin, flavonoids and alkaloids) with cancer properties, associated with infinite synthetic possibilities for obtaining analogous compounds, creates a huge chemical environment with potential to be explored, and creates a major difficulty, for screening studies to select compounds with more promising activity for a selected target. CADD techniques appear to be the least expensive and most efficient alternatives to perform virtual screening studies, aiming to selected compounds with better activity profiles and better "drugability".

BIRB796, an Inhibitor of p38 Mitogen-Activated Protein Kinase, Inhibits Proliferation and Invasion in Glioblastoma Cells

Glioblastoma (GBM) is the most common malignant tumor, and it is characterized by high cellular proliferation and invasion in the central nervous system of adults. Due to its high degree of heterogeneity and mortality, there is no effective therapy for GBM. In our study, we investigated the effect of the p38-MAPK signaling pathway inhibitor BIRB796 on GBM cells. Cell Counting Kit-8 (CCK-8) assay, 5-ethynyl-2'-deoxyuridine (EDU) staining, and cell cycle distribution analysis were performed, and the results showed that BIRB796 decreased proliferation in U87 and U251 cells. Moreover, wound healing and invasion assays were performed, which showed that BIRB796 inhibited the migration and invasion of human GBM cells. We found that BIRB796 treatment significantly decreased the formation of the cytoskeleton and thus downregulated the movement ability of the cells, as shown by phalloidin staining and vimentin immunofluorescence staining. Real-time polymerase chain reaction showed that the mRNA levels of MMP-2, Vimentin, CyclinD1, and Snail-1 were downregulated. Consistently, the expressions of MMP-2, Vimentin, CyclinD1, and p-p38 were also decreased after BIRB796 treatment. Taken together, all our results demonstrated that BIRB796 could play an antitumor role by inhibiting the proliferation and invasion in GBM cells. Thus, BIRB796 may be used as an adjuvant therapy to improve the therapeutic efficacy of GBM treatment.

Aurora kinase inhibitors: a patent review (2014-2020)

Introduction: Aurora kinases are a family of serine/threonine kinases, and promote mitotic spindle assembly by regulating centrosome duplication and separation. Aurora kinases are overexpressed in a variety of tumor cell lines, thus, the use of Aurora kinase small-molecule inhibitors has become a potential treatment option for cancer.Areas covered: As a continuing review of Aurora kinase inhibitors and their patents published in 2009, 2011 and 2014. Herein, we updated the information for Aurora kinase inhibitors in clinical trials and the patents filed from 2014 to 2020. PubMed, Scopus, SciFinder, and www.clinicaltrials.gov databases were used for searching the clinical information and patents of Aurora kinase inhibitors.Expert opinion: Even though Aurora A or B selective as well as pan inhibitors show preclinical and clinical efficacy, so far, no Aurora kinase inhibitor has been approved for clinical use. Preliminary evidence suggested that highly selective Aurora kinase or multi-target inhibitors as a single agent as well as in combination therapy are still the current main development trend of Aurora kinase inhibitors.

Tumor-infiltrating CD8+ T cell antitumor efficacy and exhaustion: molecular insights

Host immunity has an essential role in the clinical management of cancers. Therefore, it is advantageous to choose therapies that can promote tumor cell death and concurrently boost host immunity. The dynamic tumor microenvironment (TME) determines whether an antineoplastic drug will elicit favorable or disparaging immune responses from tumor-infiltrating lymphocytes (TILs). CD8+ T cells are one of the primary tumor-infiltrating immune cells that deliver antitumor responses. Here, we review the influence of various factors in the TME on CD8+ T cell exhaustion and survival, and possible strategies for restoring CD8+ T cell effector function through immunotherapy.

Diosgenin Derivatives as Potential Antitumor Agents: Synthesis, Cytotoxicity, and Mechanism of Action

Thirty-two new diosgenin derivatives were designed, synthesized, and evaluated for their cytotoxic activities in three human cancer cell lines (A549, MCF-7, and HepG2) and normal human liver cells (L02) using an MTT assay in vitro. Most compounds, especially 8, 18, 26, and 30, were more potent when compared with diosgenin. The structure-activity relationship results suggested that the presence of a succinic acid or glutaric acid linker, a piperazinyl amide terminus, and lipophilic cations are all beneficial for promoting cytotoxic activity. Notably, compound 8 displayed excellent cytotoxic activity against HepG2 cells (IC₅₀ = 1.9 μM) and showed relatively low toxicity against L02 cells (IC₅₀ = 18.6 μM), showing some selectivity between normal and tumor cells. Studies on its cellular mechanism of action showed that compound 8 induces G0/G1 cell cycle arrest and apoptosis in HepG2 cells. Predictive studies indicated that p38α mitogen-activated protein kinase (MAPK) is the optimum target of 8 based on its 3D molecular similarity, and docking studies showed that compound 8 fits well into the active site of p38α-MAPK and forms relatively strong interactions with the surrounding amino acid residues. Accordingly, compound 8 may be used as a promising lead compound for the development of new antitumor agents.

Understanding Abnormal c-JNK/p38MAPK Signaling in Amyotrophic Lateral Sclerosis: Potential Drug Targets and Influences on Neurological Disorders

c-JNK (c-Jun N-terminal kinase) and p38 mitogen-activated protein kinase (MAPK) family members work in a cell-specific manner to regulate neuronal signals. The abnormal activation of these cellular signals can cause glutamate excitotoxicity, disrupted protein homeostasis, defective axonal transport, and synaptic dysfunction. Various pre-clinical and clinical findings indicate that the up-regulation of c-JNK and p38MAPK signaling is associated with neurological disorders. Exceptionally, a significant amount of experimental data has recently shown that dysregulated c-JNK and p38MAPK are implicated in the damage to the central nervous system, including amyotrophic lateral sclerosis. Furthermore, currently available information has shown that c- JNK/p38MAPK signaling inhibitors may be a promising therapeutic alternative for improving histopathological, functional, and demyelination defects related to motor neuron disabilities. Understanding the abnormal activation of c-JNK/p38MAPK signaling and the prediction of motor neuron loss may help identify important therapeutic interventions that could prevent neurocomplications. Based on the involvement of c-JNK/p38MAPK signaling in the brain, we have assumed that the downregulation of the c-JNK/p38MAPK signaling pathway could trigger neuroprotection and neurotrophic effects towards clinicopathological presentations of ALS and other brain diseases. Thus, this research-based review also outlines the inhibition of c-JNK and p38MAPK signal downregulation in the pursuit of disease-modifying therapies for ALS.

Pharmacophore hybridization approach to discover novel pyrazoline-based hydantoin analogs with anti-tumor efficacy

In search for new and safer anti-cancer agents, a structurally guided pharmacophore hybridization strategy of two privileged scaffolds, namely diaryl pyrazolines and imidazolidine-2,4-dione (hydantoin), was adopted resulting in a newfangled series of compounds (H1-H22). Herein, a bio-isosteric replacement of "pyrrolidine-2,5-dione" moiety of our recently reported antitumor hybrid incorporating diaryl pyrazoline and pyrrolidine-2,5-dione scaffolds with "imidazoline-2,4-dione" moiety has been incorporated. Complete biological studies revealed the most potent analog among all i.e. compound H13, which was at-least 10-fold more potent compared to the corresponding pyrrolidine-2,5-dione, in colon and breast cancer cells. In-vitro studies showed activation of caspases, arrest of G0/G1 phase of cell cycle, decrease in the expression of anti-apoptotic protein (Bcl-2) and increased DNA damage. In-vivo assay on HT-29 (human colorectal adenocarcinoma) animal xenograft model unveiled the significant anti-tumor efficacy along with oral bioavailability with maximum TGI 36% (i.p.) and 44% (per os) at 50 mg/kg dose. These findings confirm the suitability of hybridized pyrazoline and imidazolidine-2,4-dione analog H13 for its anti-cancer potential and starting-point for the development of more efficacious analogs.

The roles of signaling pathways in SARS-CoV-2 infection; lessons learned from SARS-CoV and MERS-CoV

The number of descriptions of emerging viruses has grown at an unprecedented rate since the beginning of the 21^st century. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes coronavirus disease 2019 (COVID-19), is the third highly pathogenic coronavirus that has introduced itself into the human population in the current era, after SARS-CoV and Middle East respiratory syndrome coronavirus (MERS-CoV). Molecular and cellular studies of the pathogenesis of this novel coronavirus are still in the early stages of research; however, based on similarities of SARS-CoV-2 to other coronaviruses, it can be hypothesized that the NF-κB, cytokine regulation, ERK, and TNF-α signaling pathways are the likely causes of inflammation at the onset of COVID-19. Several drugs have been prescribed and used to alleviate the adverse effects of these inflammatory cellular signaling pathways, and these might be beneficial for developing novel therapeutic modalities against COVID-19. In this review, we briefly summarize alterations of cellular signaling pathways that are associated with coronavirus infection, particularly SARS-CoV and MERS-CoV, and tabulate the therapeutic agents that are currently approved for treating other human diseases.

A statistical framework for assessing pharmacological responses and biomarkers using uncertainty estimates

High-throughput testing of drugs across molecular-characterised cell lines can identify candidate treatments and discover biomarkers. However, the cells' response to a drug is typically quantified by a summary statistic from a best-fit dose-response curve, whilst neglecting the uncertainty of the curve fit and the potential variability in the raw readouts. Here, we model the experimental variance using Gaussian Processes, and subsequently, leverage uncertainty estimates to identify associated biomarkers with a new Bayesian framework. Applied to in vitro screening data on 265 compounds across 1074 cancer cell lines, our models identified 24 clinically established drug-response biomarkers, and provided evidence for six novel biomarkers by accounting for association with low uncertainty. We validated our uncertainty estimates with an additional drug screen of 26 drugs, 10 cell lines with 8 to 9 replicates. Our method is applicable to any dose-response data without replicates, and improves biomarker discovery for precision medicine.

Phase 1 trial of ralimetinib (LY2228820) with radiotherapy plus concomitant temozolomide in the treatment of newly diagnosed glioblastoma

BACKGROUND AND PURPOSE

This phase 1 trial aimed to determine the maximum tolerated dose (MTD; primary objective) of a p38-MAPK inhibitor, ralimetinib, with radiotherapy (RT) and chemotherapy (TMZ), in the treatment of newly diagnosed glioblastoma (GBM) patients.

MATERIALS AND METHODS

The study was designed as an open-label dose-escalation study driven by a Tite-CRM design and followed by an expansion cohort. Ralimetinib was administered orally every 12 h, 7 days a week, for 2 cycles of 2 weeks at a dose of 100, 200 or 300 mg/12 h. Patients received ralimetinib added to standard concurrent RT (60 Gy in 30 fractions) with TMZ (75 mg/m²/day) and 6 cycles of adjuvant TMZ (150-200 mg/m² on days 1-5 every 28 days).

RESULTS

The MTD of ralimetinib was 100 mg/12 h with chemoradiotherapy. The three patients treated at 200 mg/12 h presented a dose-limiting toxicity: one patient had a grade 3 face edema, and two patients had a grade 3 rash and grade 3 hepatic cytolysis (66%). Of the 18 enrolled patients, 15 received the MTD of ralimetinib. At the MTD, the grade ≥ 3 adverse events during concomitant chemoradiotherapy were hepatic cytolysis (2/15 patients), dermatitis/rash (1/15), lymphopenia (1/15) and nausea/vomiting (1/15). No interaction of TMZ and ralimetinib when administrated concomitantly has been observed. Inhibition of pMAPKAP-K2 (-54%) was observed in peripheral blood mononuclear cells.

CONCLUSION

This phase 1 trial is the first trial to study the combination of a p38-MAPK inhibitor, ralimetinib, with radiotherapy (RT) and chemotherapy (TMZ), in the treatment of newly diagnosed glioblastoma (GBM) patients. The MTD of ralimetinib was 100 mg/12 h. The most frequent dose-limiting toxicities were hepatic cytolysis and rash.

Mitogen-Activated Protein Kinase Inhibitors and T-Cell-Dependent Immunotherapy in Cancer

Mitogen-activated protein kinase (MAPK) signaling networks serve to regulate a wide range of physiologic and cancer-associated cell processes. For instance, a variety of oncogenic mutations often lead to hyperactivation of MAPK signaling, thereby enhancing tumor cell proliferation and disease progression. As such, several components of the MAPK signaling network have been proposed as viable targets for cancer therapy. However, the contributions of MAPK signaling extend well beyond the tumor cells, and several MAPK effectors have been identified as key mediators of the tumor microenvironment (TME), particularly with respect to the local immune infiltrate. In fact, a blockade of various MAPK signals has been suggested to fundamentally alter the interaction between tumor cells and T lymphocytes and have been suggested a potential adjuvant to immune checkpoint inhibition in the clinic. Therefore, in this review article, we discuss the various mechanisms through which MAPK family members contribute to T-cell biology, as well as circumstances in which MAPK inhibition may potentiate or limit cancer immunotherapy.

The LIV-1-GRPEL1 axis adjusts cell fate during anti-mitotic agent-damaged mitosis

Background

Understanding how cells respond to mitotic poisons is of great biomedical and clinical significance. However, it remains unknown how cell-death or survival is determined during exposure to anti-mitotic drugs.

Methods

The biological effects of SLC39A6 (LIV-1) and GrpE-like 1 (GRPEL1) on mitotic exit and apoptosis were evaluated both in vitro and in vivo using flow cytometry, western blotting, xenografts and time-lapse imaging. The interactions between proteins and the ubiquitination of GRPEL1 were assessed by GST pull down, immunoprecipitation and mass spectrometry analysis. The expression of LIV-1 in cancers was assessed by immunohistochemistry.

Findings

Overexpression of LIV-1 led to direct apoptosis. Depleted for LIV-1 evade anti-mitotic agent-induced killing through a rapid exit from arrested mitosis. LIV-1 interacts with GRPEL1 and Stabilizes GRPEL1 Protein by Preventing Ubiquitylation of GRPEL1. LIV-1-GRPEL1 axis depletion works to reduce the mitotic arrest by inducing PP2A-B55α phosphates activity, while inhibit apoptosis by banding AIF and preventing the latter's release into the nucleus. Loss of function in this axis was frequent in multiple types of human epithelial cancer.

Interpretation

These data demonstrate that LIV-1-GRPEL1 axis dually regulates mitotic exit as well as apoptosis by interacting with PP2A B55α and AIF. Its discovery constitutes a conceptual advance for the decisive mechanism of cell fate during damaged mitosis.

Fund

National Clinical Research Center for Obstetric and Gynecologic Diseases, the National Natural Science Foundation of China.

Cathepsin C Interacts with TNF-α/p38 MAPK Signaling Pathway to Promote Proliferation and Metastasis in Hepatocellular Carcinoma

Purpose

Although cathepsin C (CTSC) has been reported to maintain malignant biological properties in various cancers, its functions in hepatocellular carcinoma (HCC) remain obscure. We aimed to investigate the potential role of CTSC in HCC.

Materials and Methods

HCC tissue microarrays (n=122) were employed to analyze the correlation between CTSC expression and clinicopathological characteristics through immunohistochemistry staining. Quantitative real-time polymerase chain reaction, western blot assay, Cell Counting Kit-8 assay, colony formation, cell migration, and invasion assays, xenograft mice model were adopted to validate what had been indicated by the bioinformatic web tools.

Results

By bioinformatic tools and tissue microarrays, CTSC was found upregulated in HCC compared with normal liver tissues, and its higher expression was correlated with poor prognosis of HCC patients (hazard ratio, 2.402; 95% confidence interval, 1.493 to 3.865; p < 0.001). By gain/loss-of-function assays, we implicated that CTSC functioned as an oncogene to promote the proliferation and metastasis of HCC cells. Mechanistically, we revealed that CTSC was involved in several cancer-related signaling pathways by Gene Set Enrichment Analysis, among which tumor necrosis factor α (TNF-α)/p38 pathway was verified to be activated by CTSC. Furthermore, we found that TNF-α could activate CTSC expression in a concentration- dependent manner. Ralimetinib, an oral p38 mitogen-activated protein kinase (MAPK) inhibitor could inhibit CTSC expression. These indicated a potential positive feedback loop between CTSC and TNF-α/MAPK (p38) signaling.

Conclusion

Taken together, CTSC plays an important role in the growth and metastasis of HCC and may be a promising therapeutic target upon HCC.

Novel urokinase-plasminogen activator inhibitor SPINK13 inhibits growth and metastasis of hepatocellular carcinoma in vivo

Advanced hepatocellular carcinoma (HCC) is a highly aggressive malignancy that is a serious threat to the public health system of China. Urokinase-plasminogen activator (uPA) can promote the invasive growth and metastasis of HCC cells by activating matrix metalloproteinases (MMPs), leading to the breakage of the extra-cellular matrix. uPA is a promising target for advanced HCC treatment. In this stuy the expression of uPA was examined by quantitative polymerase chain reaction in hepatic cell lines. Protein interaction between uPA and SPINK13 was identified by immunoprecipitation. In vitro biochemical assay was used to examine the inhibitory effect of the SPINK13 on the direct cleaving of the recombinant pro-MMP9 by uPA. The antitumor effect of SPINK13 was examined by transwell assay or the nude mice tumor model.The expression of uPA was much higher in highly aggressive HCC cell lines than in lowly aggressive HCC cell lines or non-tumor hepatic cell lines. SPINK13 interacted with uPA in HCC cells and directly inhibited the cleaving of MMP9 by uPA. Treatment of the recombinant SPINK13 protein inhibited the invasion of HCC cells in several experiments, such as transwell experiments or the intrahepatic growth model. The results of the study indicated that SPINK13 could function as a promising therapeutic approach for patients with advanced HCC.

Aurora kinase inhibitor VX‑680 suppresses the proliferation and migration of HUVECs and angiogenesis

Angiogenesis serves a key role in tumor growth and metastasis. VX‑680, a potent inhibitor targeting the Aurora kinase family, is widely used in the inhibition of tumor progression. However, the effect of VX‑680 on angiogenesis remains unknown. The present study identified that VX‑680 inhibited human umbilical vein endothelial cell (HUVEC) proliferation and promoted HUVEC apoptosis by inducing the cleavage of PARP and caspase‑3. VX‑680 also markedly decreased the migration and tube formation of HUVECs in a dose‑dependent manner. In addition, VX‑680 significantly suppressed the formation of blood vessels in a dose‑dependent manner confirmed by a chicken embryo chorioallantoic membrane assay in vivo. Furthermore, VX‑680 inhibited the expression levels of vascular endothelial growth factor and phosphorylated RAC‑α serine/threonine‑protein kinase in HUVECs. These results suggested that VX‑680 suppressed angiogenesis and may be a potential novel anti‑angiogenic agent.

Human p38α mitogen-activated protein kinase in the Asp168-Phe169-Gly170-in (DFG-in) state can bind allosteric inhibitor Doramapimod

Doramapimod (BIRB-796) is widely recognized as one of the most potent and selective type II inhibitors of human p38α mitogen-activated protein kinase (MAPK); however, the understanding of its binding mechanism remains incomplete. Previous studies indicated high affinity of the ligand to a so-called allosteric pocket revealed only in the 'out' state of the DFG motif (i.e. Asp168-Phe169-Gly170) when Phe169 becomes fully exposed to the solvent. The possibility of alternative binding in the DFG-in state was hypothesized, but the molecular mechanism was not known. Methods of bioinformatics, docking and long-time scale classical and accelerated molecular dynamics have been applied to study the interaction of Doramapimod with the human p38α MAPK. It was shown that Doramapimod can bind to the protein even when the Phe169 is fully buried inside the allosteric pocket and the kinase activation loop is in the DFG-in state. Orientation of the inhibitor in such a complex is significantly different from that in the known crystallographic complex formed by the kinase in the DFG-out state; however, the Doramapimod's binding is followed by the ligand-induced conformational changes, which finally improve accommodation of the inhibitor. Molecular modelling has confirmed that Doramapimod combines the features of type I and II inhibitors of p38α MAPK, i.e. can directly and indirectly compete with the ATP binding. It can be concluded that optimization of the initial binding in the DFG-in state and the final accommodation in the DFG-out state should be both considered at designing novel efficient type II inhibitors of MAPK and homologous proteins. Communicated by Ramaswamy H. Sarma.

1,2,4-Trisubstituted imidazolinones with dual carbonic anhydrase and p38 mitogen-activated protein kinase inhibitory activity

Various 1,2,4 trisubstituted imidazolin-5-one derivatives were synthesized and evaluated for their inhibitory activity against p38 mitogen-activated protein kinase (p38MAPK) and carbonic anhydrase (CA) enzymes aiming to explore potential dual inhibitors. Results revealed that compounds 3c, 3g, 3h, 4a, 6c and 6d were the most effective derivatives against p38αMAPK (IC₅₀ = 0.14, 0.14, 0.056, 0.14, 0.13 and 0.14 μM, respectively) compared to sorafenib (IC₅₀ = 1.58 μM) as standard drug. On the other hand, compound 4a revealed the best inhibitory activity against all the tested carbonic anhydrase isoforms CA I, II, IV and IX with K_i values of 95.0, 0.83, 6.90 and 12.4 nM, respectively compared to acetazolamide with K_i values 250, 12.1, 74 and 12.8 nM, respectively. Therefore, compound 4a can be considered as a potent dual p38αMAPK/CA inhibitor.

JNK, p38, ERK, and SGK1 Inhibitors in Cancer

Mitogen-activated protein kinases (MAP kinases) are a family of kinases that regulates a range of biological processes implicated in the response to growth factors like latelet-derived growth factor (PDGF), epidermal growth factor (EGF), vascular endothelial growth factor (VEGF), and stress, such as ultraviolet irradiation, heat shock, and osmotic shock. The MAP kinase family consists of four major subfamilies of related proteins (extracellular regulated kinases 1/2 (ERK1/2), c-Jun N-terminal kinase (JNK), p38, and extracellular regulated kinase 5 (ERK5)) and regulates numerous cellular activities, such as apoptosis, gene expression, mitosis, differentiation, and immune responses. The deregulation of these kinases is shown to be involved in human diseases, such as cancer, immune diseases, inflammation, and neurodegenerative disorders. The awareness of the therapeutic potential of the inhibition of MAP kinases led to a thorough search for small-molecule inhibitors. Here, we discuss some of the most well-known MAP kinase inhibitors and their use in cancer research.

Novel proteasome inhibitor delanzomib sensitizes cervical cancer cells to doxorubicin-induced apoptosis via stabilizing tumor suppressor proteins in the p53 pathway

Cervical cancer, the third most commonly occurring cancer, is the second leading cause of cancer related mortality among women. Aberrant ubiquitination and proteasome activity, both human papillomavirus and tumor derived, have been shown to contribute to tumor angiogenesis, proliferation, and invasion in many cancers, including cervical cancer. Thus, small molecule proteasome inhibitors are a potential and strategic treatment option for cervical cancer. In this study, novel proteasome inhibitor delanzomib (CEP-18770) exhibited potent pro-apoptotic and cytotoxic effects on a panel of cervical cancer cell lines by blocking proteasomal activity. Delanzomib also significantly sensitized cervical cancer cells to treatment of doxorubicin (Dox), a traditional chemotherapeutic agent. Furthermore, proteasome inhibition revealed stabilization of p53 and p53 transcriptional targets and induction of p38/JNK phosphorylation. Additionally, delanzomib worked synergistically with Dox to further upregulate p53 and its downstream targets and enhanced Dox-induced p38 phosphorylation. Our study strongly supports the 26S proteasome as a potential therapeutic target in cervical cancer and proteasome inhibition by delanzomib may be a potential treatment strategy for cervical cancer patients.

Synthesis and Evaluation of New Pyrazoline Derivatives as Potential Anticancer Agents in HepG-2 Cell Line

Cancer is a major public health concern worldwide. Adverse effects of cancer treatments still compromise patients' quality of life. To identify new potential anticancer agents, a series of novel pyrazoline derivatives were synthesized and evaluated for cytotoxic effects on HepG-2 (human liver hepatocellular carcinoma cell line) and primary hepatocytes. Compound structures were confirmed by ¹H-NMR, mass spectrometry, and infrared imaging. An in vitro assay demonstrated that several compounds exerted cytotoxicity in the micromolar range. Benzo[b]thiophen-2-yl-[5-(4-hydroxy-3,5-dimethoxy-phenyl)-3-(2-hydroxy-phenyl)-4,5-dihydo-pyrazol-1-yl]-methanone (b17) was the most effective anticancer agent against HepG-2 cells owing to its notable inhibitory effect on HepG-2 with an IC₅₀ value of 3.57 µM when compared with cisplatin (IC₅₀ = 8.45 µM) and low cytotoxicity against primary hepatocytes. Cell cycle analysis and apoptosis/necrosis evaluation using this compound revealed that b17 notably arrested HepG-2 cells in the G₂/M phase and induced HepG-2 cells apoptosis. Our findings indicate that compound b17 may be a promising anticancer drug candidate.