Targeting the PI3K/AKT/mTOR pathway in estrogen receptor-positive breast cancer. Cancer Treat Rev. 2014;40:862-871. [PMID: 24774538 DOI: 10.1016/j.ctrv.2014.03.004]

Development of a reliable cell-based reporter gene assay to measure the bioactivity of anti-HER2 therapeutic antibodies

Human epidermal growth factor receptor 2 (HER2) is a key player in the pathogenesis and progression of breast cancer and is currently a primary target for breast cancer immunotherapy. Bioactivity determination is necessary to guarantee the safety and efficacy of therapeutic antibodies targeting HER2. Nevertheless, currently available bioassays for measuring the bioactivity of anti-HER2 mAbs are either not representative or have high variability. Here, we established a reliable reporter gene assay (RGA) based on T47D-SRE-Luc cell line that expresses endogenous HER2 and luciferase controlled by serum response element (SRE) to measure the bioactivity of anti-HER2 antibodies. Neuregulin-1 (NRG-1) can lead to the heterodimerization of HER2 on the cell membrane and induce the expression of downstream SRE-controlled luciferase, while pertuzumab can dose-dependently reverse the reaction, resulting in a good dose-response curve reflecting the activity of the antibody. After optimizing the relevant assay parameters, the established RGA was fully validated based on ICH-Q2 (R1), which demonstrated that the method had excellent specificity, accuracy, precision, linearity, and stability. In summary, this robust and innovative bioactivity determination assay can be applied in the development and screening, release control, biosimilar assessment and stability studies of anti-HER2 mAbs.

Hormonal regulation of miRNA during mammary gland development

The mammary gland is a unique organ as most of its development occurs after birth through stages of proliferation, differentiation and apoptosis that are tightly regulated by circulating hormones and growth factors. Throughout development, hormonal cues induce the regulation of different pathways, ultimately leading to differential transcription and expression of genes involved in this process, but also in the activation or inhibition of post-transcriptional mechanisms of regulation. However, the role of microRNAs (miRNAs) in the different phases of mammary gland remodeling is still poorly understood. The objectives of this study were to analyze the expression of miRNA in key stages of mammary gland development in mice and to determine whether it could be associated with hormonal variation between stages. To do so, miRNAs were isolated from mouse mammary glands at stages of adulthood, pregnancy, lactation and involution, and sequenced. Results showed that 490, 473, 419, and 460 miRNAs are detected in adult, pregnant, lactating and involuting mice, respectively, most of them being common to all four groups, and 58 unique to one stage. Most genes could be divided into six clusters of expression, including two encompassing the highest number of miRNA (clusters 1 and 3) and showing opposite profiles of expression, reaching a peak at adulthood and valley at lactation, or showing the lowest expression at adulthood and peaking at lactation. GO and KEGG analyses suggest that the miRNAs differentially expressed between stages influence the expression of targets associated with mammary gland homeostasis and hormone regulation. To further understand the links between miRNA expression and hormones involved in mammary gland development, miRNAs were then sequenced in breast cells exposed to estradiol, progesterone, prolactin and oxytocin. Four, 38, 24 and 66 miRNAs were associated with progesterone, estradiol, prolactin, and oxytocin exposure, respectively. Finally, when looking at miRNAs modulated by the hormones, differentially expressed during mammary gland development, and having a pattern of expression that could be correlated with the relative levels of hormones known to be found in vivo, 16 miRNAs were identified as likely regulated by circulating hormones. Overall, our study brings a better understanding of the regulation of miRNAs throughout mammary gland development and suggests that there is a relationship between their expression and the main hormones involved in mammary gland development. Future studies will examine this role more in detail.

EZH2: The roles in targeted therapy and mechanisms of resistance in breast cancer

Drug resistance presents a formidable challenge in the realm of breast cancer therapy. Accumulating evidence suggests that enhancer of zeste homolog 2 (EZH2), a component of the polycomb repressive complex 2 (PRC2), may serve as a key regulator in controlling drug resistance. EZH2 overexpression has been observed in breast cancer and many other malignancies, showing a strong correlation with poor outcomes. This review aims to summarize the mechanisms by which EZH2 regulates drug resistance, with a specific focus on breast cancer, in order to provide a comprehensive understanding of the underlying molecular processes. Additionally, we will discuss the current strategies and outcomes of targeting EZH2 using both single agents and combination therapies, with the goal of offering improved guidance for the clinical treatment of breast cancer patients who have developed drug resistance.

Computational framework for identifying and evaluating mutagenic and xenoestrogenic potential of food additives

Food additives are chemicals incorporated in food to enhance its flavor, color and prevent spoilage. Some of these are associated with substantial health hazards, including developmental disorders, increase cancer risk, and hormone disruption. Hence, this study aimed to comprehend the in-silico toxicology framework for evaluating mutagenic and xenoestrogenic potential of food additives and their association with breast cancer. A total of 2885 food additives were screened for toxicity based on Threshold of Toxicological Concern (TTC), mutagenicity endpoint prediction, and mutagenic structural alerts/toxicophores identification. Ten food additives were identified as having mutagenic potential based on toxicity screening. Furthermore, Protein-Protein Interaction (PPI) analysis identified ESR1, as a key hub gene in breast cancer. KEGG pathway analysis verified that ESR1 plays a significant role in breast cancer pathogenesis. Additionally, competitive interaction studies of the predicted potential mutagenic food additives with the estrogen receptor-α were evaluated at agonist and antagonist binding sites. Indole, Dichloromethane, Trichloroethylene, Quinoline, 6-methyl quinoline, Ethyl nitrite, and 4-methyl quinoline could act as agonists, and Paraldehyde, Azodicarbonamide, and 2-acetylfuranmay as antagonists. The systematic risk assessment framework reported in this study enables the exploration of mutagenic and xenoestrogenic potential associated with food additives for hazard identification and management.

Female-specific dysfunction of sensory neocortical circuits in a mouse model of autism mediated by mGluR5 and estrogen receptor α

Little is known of the brain mechanisms that mediate sex-specific autism symptoms. Here, we demonstrate that deletion of the autism spectrum disorder (ASD)-risk gene, Pten, in neocortical pyramidal neurons (NSEPten knockout [KO]) results in robust cortical circuit hyperexcitability selectively in female mice observed as prolonged spontaneous persistent activity states. Circuit hyperexcitability in females is mediated by metabotropic glutamate receptor 5 (mGluR5) and estrogen receptor α (ERα) signaling to mitogen-activated protein kinases (Erk1/2) and de novo protein synthesis. Pten KO layer 5 neurons have a female-specific increase in mGluR5 and mGluR5-dependent protein synthesis. Furthermore, mGluR5-ERα complexes are generally elevated in female cortices, and genetic reduction of ERα rescues enhanced circuit excitability, protein synthesis, and neuron size selectively in NSEPten KO females. Female NSEPten KO mice display deficits in sensory processing and social behaviors as well as mGluR5-dependent seizures. These results reveal mechanisms by which sex and a high-confidence ASD-risk gene interact to affect brain function and behavior.

From desert flora to cancer therapy: systematic exploration of multi-pathway mechanisms using network pharmacology and molecular modeling approaches

Ovarian cancer, often labeled a "silent killer," remains one of the most compelling and challenging areas of cancer research. In 2019 alone, a staggering 222,240 new cases of ovarian cancer were reported, with nearly 14,170 lives tragically lost to this relentless disease. The absence of effective diagnostic methods, increased resistance to chemotherapy, and the heterogeneous nature of ovarian cancer collectively contribute to the unfavorable prognosis observed in the majority of cases. Thus, there is a pressing need to explore therapeutic interventions that offer superior efficacy and safety, thereby enhancing the survival prospects for ovarian cancer patients. Recognizing this potential, our research synergizes bioinformatics with a network pharmacology approach to investigate the underlying molecular interactions of Saudi Arabian flora (Onopordum heteracanthum, Acacia ehrenbergiana, Osteospermum vaillantii, Cyperus rotundus, Carissa carandas, Carissa spinarum, and Camellia sinensis) in ovarian cancer treatment. At first, phytoconstituents of indigenous flora and their associated gene targets, particularly those pertinent to ovarian cancer, were obtained from open-access databases. Later, the shared targets of plants and diseases were compared to identify common targets. A protein-protein interaction (PPI) network of predicted targets was then constructed for the identification of key genes having the highest degree of connectivity among networks. Following that, a compound-target protein-pathway network was constructed, which uncovered that, namely, hispidulin, stigmasterol, ascorbic acid, octopamine, cyperene, kaempferol, pungenin, citric acid, d-tartaric acid, beta-sitosterol, (-)-epicatechin gallate, and (+)-catechin demonstrably influence cell proliferation and growth by impacting the AKT1 and VEGFA proteins. Molecular docking, complemented by a 20-ns molecular dynamic (MD) simulation, was used, and the binding affinity of the compound was further validated. Molecular docking, complemented by a 20-ns MD simulation, confirmed the binding affinity of these compounds. Specifically, for AKT1, ascorbic acid showed a docking score of -11.1227 kcal/mol, interacting with residues Ser A:240, Leu A:239, Arg A:243, Arg C:2, and Glu A:341. For VEGFA, hispidulin exhibited a docking score of -17.3714 kcal/mol, interacting with Asn A:158, Val A:190, Gln B:160, Ser A:179, and Ser B:176. To sum up, both a theoretical and empirical framework were established by this study, directing more comprehensive research and laying out a roadmap for the potential utilization of active compounds in the formulation of anti-cancer treatments.

Female specific dysfunction of sensory neocortical circuits in a mouse model of autism mediated by mGluR5 and Estrogen Receptor α

Autism manifests differently in males and females and the brain mechanisms that mediate these sex-dependent differences are unknown. Here, we demonstrate that deletion of the ASD-risk gene, Pten, in neocortical pyramidal neurons (NSE Pten KO) results in robust hyperexcitability of local neocortical circuits in female, but not male, mice, observed as prolonged, spontaneous persistent activity states (UP states). Circuit hyperexcitability in NSE Pten KO mice is mediated by enhanced and/or altered signaling of metabotropic glutamate receptor 5 (mGluR5) and estrogen receptor α (ERα) to ERK and protein synthesis selectively in Pten deleted female neurons. In support of this idea, Pten deleted Layer 5 cortical neurons have female-specific increases in mGluR5 and mGluR5-driven protein synthesis. In addition, mGluR5-ERα complexes are elevated in female cortex and genetic reduction of ERα in Pten KO cortical neurons rescues circuit excitability, protein synthesis and enlarged neurons selectively in females. Abnormal timing and hyperexcitability of neocortical circuits in female NSE Pten KO mice are associated with deficits in temporal processing of sensory stimuli and social behaviors as well as mGluR5-dependent seizures. Female-specific cortical hyperexcitability and mGluR5-dependent seizures are also observed in a human disease relevant mouse model, germline Pten +/- mice. Our results reveal molecular mechanisms by which sex and a high impact ASD-risk gene interact to affect brain function and behavior.

Macrophages Promote Subtype Conversion and Endocrine Resistance in Breast Cancer

BACKGROUND

The progression of tumors from less aggressive subtypes to more aggressive states during metastasis poses challenges for treatment strategies. Previous studies have revealed the molecular subtype conversion between primary and metastatic tumors in breast cancer (BC). However, the subtype conversion during lymph node metastasis (LNM) and the underlying mechanism remains unclear.

METHODS

We compared clinical subtypes in paired primary tumors and positive lymph nodes (PLNs) in BC patients and further validated them in the mouse model. Bioinformatics analysis and macrophage-conditioned medium treatment were performed to investigate the role of macrophages in subtype conversion.

RESULTS

During LNM, hormone receptors (HRs) were down-regulated, while HER2 was up-regulated, leading to the transformation of luminal A tumors towards luminal B tumors and from luminal B subtype towards HER2-enriched (HER2-E) subtype. The mouse model demonstrated the elevated levels of HER2 in PLN while retaining luminal characteristics. Among the various cells in the tumor microenvironment (TME), macrophages were the most clinically relevant in terms of prognosis. The treatment of a macrophage-conditioned medium further confirmed the downregulation of HR expression and upregulation of HER2 expression, inducing tamoxifen resistance. Through bioinformatics analysis, MNX1 was identified as a potential transcription factor governing the expression of HR and HER2.

CONCLUSION

Our study revealed the HER2-E subtype conversion during LNM in BC. Macrophages were the crucial cell type in TME, inducing the downregulation of HR and upregulation of HER2, probably via MNX1. Targeting macrophages or MNX1 may provide new avenues for endocrine therapy and targeted treatment of BC patients with LNM.

A network pharmacology integrated serum pharmacochemistry strategy for uncovering efficacy of YXC on hepatocellular carcinoma

ETHNOPHARMACOLOGICAL RELEVANCE

The YangzhengXiaoji capsule (YXC) has a wide range of applications as effective traditional Chinese medicine (TCM) preparation for hepatocellular carcinoma (HCC) in China. However, the potential bioactive components and the mechanisms are yet unclear.

AIM OF THE STUDY

The treatment mechanism of YXC on HCC using a network pharmacology integrated serum pharmacochemistry strategy to investigate associated targets and pathways.

MATERIALS AND METHODS

We utilised HPLC-Q-TOF-MS/MS technology to identify components of the serum samples from both the model group and the YXC (H) group serum, which were collected from nude mice with orthotopic liver tumours. Following this, we conducted compound-target prediction and identified the overlap between the target genes in the YXC group and the oncogenes associated with HCC. The anticancer mechanisms of YXC were investigated by creating a compound-target-pathway network using the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway and Gene Ontology (GO) analysis. The anticancer efficacy was evaluated in vitro and in vivo. Also, potential predictive targets and pathways associated with YXC in HCC treatment were assessed by western blotting.

RESULTS

The YXC (H) serum had 47 bioactive compounds compared to other models, and identified 173 specific target genes. Using the compound-target-disease network, 141 possible target genes were identified. The KEGG pathway analysis revealed vital enrichment of pathways associated with HCC, including regulating Oncology related pathways of inflammation, immunity, apoptosis, and necrosis biological processes. YXC significantly inhibited HCC cell growth in vitro and in vivo. After YXC treatment, western blotting detected alterations in the p53/Bcl-2/Bax/Caspase-3 and PI3K/Akt pathways.

CONCLUSIONS

YXC can inhibit HCC development and advancement by a variety of components, targets and pathways, especially apoptosis-induction.

Bibliometric analysis and visualization of endocrine therapy for breast cancer research in the last two decade

Background

Breast cancer endocrine therapy research has become a crucial domain in oncology since hormone receptor-positive breast cancers have been increasingly recognized, and targeted therapeutic interventions have been advancing over the past few years. This bibliometric analysis attempts to shed light on the trends, dynamics, and knowledge hotspots that have shaped the landscape of breast cancer endocrine therapy research between 2003 and 2022.

Methods

In this study, we comprehensively reviewed the scientific literature spanning the above-mentioned period, which included publications accessible through the database of the Web of Science (WOS) and the National Center for Biotechnology Information (NCBI). Next, a systematic and data-driven analysis supported by sophisticated software tools was conducted, such that the core themes, prolific authors, influential journals, prominent countries, and critical citation patterns in the relevant research field can be clarified.

Results

A continuous and substantial expansion of breast cancer endocrine therapy research was revealed over the evaluated period. A total of 1,317 scholarly articles were examined. The results of the analysis suggested that research on endocrine therapy for breast cancer has laid a solid basis for the treatment of hormone receptor-positive breast cancer. From a geographical perspective, the US, the UK, and China emerged as the most active contributors, illustrating the global impact of this study. Furthermore, our analysis delineated prominent research topics that have dominated the discourse in the past two decades, including drug therapy, therapeutic efficacy, molecular biomarkers, and hormonal receptor interactions.

Conclusion

This comprehensive bibliometric analysis provides a panoramic view of the ever-evolving landscape of breast cancer endocrine therapy research. The findings highlight the trajectory of past developments while signifying an avenue of vast opportunities for future investigations and therapeutic advancements. As the field continues to burgeon, this analysis will provide valuable guidance for to researchers toward pertinent knowledge hotspots and emerging trends, which can expedite the discoveries in the realm of breast cancer endocrine therapy.

Inhibitors of phosphoinositide 3-kinase (PI3K) and phosphoinositide 3-kinase-related protein kinase family (PIKK)

Phosphoinositide 3-kinases (PI3K) and phosphoinositide 3-kinase-related protein kinases (PIKK) are two structurally related families of kinases that play vital roles in cell growth and DNA damage repair. Dysfunction of PIKK members and aberrant stimulation of the PI3K/AKT/mTOR signalling pathway are linked to a plethora of diseases including cancer. In recent decades, numerous inhibitors related to the PI3K/AKT/mTOR signalling have made great strides in cancer treatment, like copanlisib and sirolimus. Notably, most of the PIKK inhibitors (such as VX-970 and M3814) related to DNA damage response have also shown good efficacy in clinical trials. However, these drugs still require a suitable combination therapy to overcome drug resistance or improve antitumor activity. Based on the aforementioned facts, we summarised the efficacy of PIKK, PI3K, and AKT inhibitors in the therapy of human malignancies and the resistance mechanisms of targeted therapy, in order to provide deeper insights into cancer treatment.

Involvement of Protein Kinase R in Double-Stranded RNA-Induced Proteasomal Degradation of Hypoxia Inducible Factor-1α

Hypoxia inducible factor-1α (HIF-1α) is a crucial therapeutic target in various diseases, including cancer and fibrosis. We previously demonstrated that transfection with double-stranded RNA (dsRNA), including polyI:C and the dsRNA genome of mammalian orthoreovirus, resulted in significant reduction in HIF-1α protein levels in cultured cells; however, it remained to be elucidated how dsRNA induced down-regulation of HIF-1α protein levels. In this study, we examined the mechanism of dsRNA-mediated down-regulation of HIF-1α protein levels. We found that among the various cellular factors involved in dsRNA-mediated innate immunity, knockdown and knockout of protein kinase R (PKR) significantly restored HIF-1α protein levels in dsRNA-transfected cells, indicating that PKR was involved in dsRNA-mediated down-regulation of HIF-1α. Proteasome inhibitors significantly restored the HIF-1α protein levels in dsRNA-transfected cells. Ubiquitination levels of HIF-1α were increased by transfection with dsRNA. These findings indicated that degradation of HIF-1α in a ubiquitin-proteasome pathway was promoted in a PKR-dependent manner following dsRNA transfection. Expression of not only HIF-1α but also several proteins, including CDK4 and HER2, was down-regulated following dsRNA transfection. These data provide important clues for elucidation of the mechanism of dsRNA-mediated cellular toxicity, as well as for therapeutic application of dsRNA.

Unfolding the role of the PI3K/AKT/MTOR pathway in male breast cancer: A pragmatic appraisal

Breast cancer in men is rare, but a relevant public health issue, yielding a 25% higher risk of mortality comparing to female counterparts. The representation of males in clinical trials has been scarce and treatment decisions are based mainly on extrapolations from data in females. In the setting of estrogen-dependent metastatic disease, the use of everolimus has been seldom reported, although the PI3K/AKT/mTOR pathway seems to be a critical oncogenic driver. This paper dissects hallmark biological features of ER+/HER2-advanced male breast cancer, setting a comprehensive basis to promote personalized care, focusing on the potential of targeting the PI3K/AKT/mTOR pathway.

Waterborne Tebuconazole Exposure Induces Male-Biased Sex Differentiation in Zebrafish (Danio rerio) Larvae via Aromatase Inhibition

Tebuconazole is a widely used fungicide for various crops that targets sterol 14-α-demethylase (CYP51) in fungi. However, attention has shifted to aromatase (CYP19) due to limited research indicating its reproductive impact on aquatic organisms. Herein, zebrafish were exposed to 0.5 mg/L tebuconazole at different developmental stages. The proportion of males increased significantly after long-term exposure during the sex differentiation phase (0-60, 5-60, and 19-60 days postfertilization (dpf)). Testosterone levels increased and 17β-estradiol and cyp19a1a expression levels decreased during the 5-60 dpf exposure, while the sex ratio was equally distributed on coexposure with 50 ng/L 17β-estradiol. Chemically activated luciferase gene expression bioassays determined that the male-biased sex differentiation was not caused by tebuconazole directly binding to sex hormone receptors. Protein expression and phosphorylation levels were specifically altered in the vascular endothelial growth factor signaling pathway despite excluding the possibility of tebuconazole directly interacting with kinases. Aromatase was selected for potential target analysis. Molecular docking and aromatase activity assays demonstrated the interactions between tebuconazole and aromatase, highlighting that tebuconazole poses a threat to fish populations by inducing a gender imbalance.

Estrogen Receptor Signaling in Breast Cancer

Estrogen receptor (ER) signaling is a critical regulator of cell proliferation, differentiation, and survival in breast cancer (BC) and other hormone-sensitive cancers. In this review, we explore the mechanism of ER-dependent downstream signaling in BC and the role of estrogens as growth factors necessary for cancer invasion and dissemination. The significance of the clinical implications of ER signaling in BC, including the potential of endocrine therapies that target estrogens' synthesis and ER-dependent signal transmission, such as aromatase inhibitors or selective estrogen receptor modulators, is discussed. As a consequence, the challenges associated with the resistance to these therapies resulting from acquired ER mutations and potential strategies to overcome them are the critical point for the new treatment strategies' development.

Systemic therapy for hormone receptor-positive/human epidermal growth factor receptor 2-negative early stage and metastatic breast cancer

Hormone receptor (HR)-positive and human epidermal growth factor receptor 2 (HER2)-negative breast cancer is defined by the presence of the estrogen receptor and/or the progesterone receptor and the absence of HER2 gene amplification. HR-positive/HER2-negative breast cancer accounts for 65%-70% of all breast cancers, and incidence increases with increasing age. Treatment varies by stage, and endocrine therapy is the mainstay of treatment in both early stage and late-stage disease. Combinations with cyclin-dependent kinase 4/6 inhibitors have reduced distant recurrence in the early stage setting and improved overall survival in the metastatic setting. Chemotherapy is used based on stage and tumor biology in the early stage setting and after endocrine resistance for advanced disease. New therapies, including novel endocrine agents and antibody-drug conjugates, are now changing the treatment landscape. With the availability of new treatment options, it is important to define the optimal sequence of treatment to maximize clinical benefit while minimizing toxicity. In this review, the authors first discuss the pathologic and molecular features of HR-positive/HER2-negative breast cancer and mechanisms of endocrine resistance. Then, they discuss current and emerging therapies for both early stage and metastatic HR-positive/HER2-negative breast cancer, including treatment algorithms based on current data.

Low-dose aspirin, statins, and metformin and survival in patients with breast cancers: a Norwegian population-based cohort study

BACKGROUND

Previous studies assessed the prognostic effect of aspirin, statins, and metformin in breast cancer (BC) patients, with inconclusive results.

METHODS

We performed a nationwide population-based cohort study to evaluate if post-diagnostic use of low-dose aspirin, statins, and metformin was associated with BC-specific survival. Women aged ≥ 50 years and diagnosed with BC in 2004-2017, who survived ≥ 12 months after diagnosis (follow-up started 12 months after diagnosis), were identified in the Cancer Registry of Norway. The Norwegian Prescription Database provided information on prescriptions. Multivariable Cox proportional hazard models were used to estimate hazard ratios (HR) and 95% confidence intervals (CI) for the association between post-diagnostic use and BC-specific survival, overall and by oestrogen receptor (ER) status.

RESULTS

A total of 26,190 patients were included. Of these, 5324 (20%), 7591 (29%), and 1495 (6%) were post-diagnostic users of low-dose aspirin, statins, and metformin, respectively. The median follow-up was 6.1 years, and 2169 (8%) patients died from BC. HRs for use, compared to no use, were estimated at 0.96 (95% CI 0.85-1.08) for low-dose aspirin (ER+: HR = 0.97, 95% CI 0.83-1.13; ER-: HR = 0.97, 95% CI 0.73-1.29, p value for interaction = 0.562), 0.84 (95% CI 0.75-0.94) for statins (ER+: HR = 0.95, 95% CI 0.82-1.09; ER-: HR = 0.77, 95% CI 0.60-1.00, p value for interaction = 0.259), and 0.70 (95% CI 0.51-0.96) for metformin (compared to use of non-metformin antidiabetics) (ER+: HR = 0.67, 95% CI 0.45-1.01; ER-: HR = 1.62, 95% CI 0.72-3.62, p value for interaction = 0.077).

CONCLUSION

We found evidence supporting an association between post-diagnostic use of statins and metformin and survival, in patients with BC. Our findings indicate potential differences according to ER status.

The Molecular and Genetic Interactions between Obesity and Breast Cancer Risk

Breast cancer (BC) is considered the leading cause of death among females worldwide. Various risk factors contribute to BC development, such as age, genetics, reproductive factors, obesity, alcohol intake, and lifestyle. Obesity is considered to be a pandemic health problem globally, affecting millions of people worldwide. Obesity has been associated with a high risk of BC development. Determining the impact of obesity on BC development risk in women by demonstrating the molecular and genetic association in pre- and post-menopause females and risk to BC initiation is crucial in order to improve the diagnosis and prognosis of BC disease. In epidemiological studies, BC in premenopausal women was shown to be protective in a certain pattern. These altered effects between the two phases could be due to various physiological changes, such as estrogen/progesterone fluctuating levels. In addition, the relationship between BC risk and obesity is indicated by different molecular alterations as metabolic pathways and genetic mutation or epigenetic DNA changes supporting a strong connection between obesity and BC risk. However, these molecular and genetic alteration remain incompletely understood. The aim of this review is to highlight and elucidate the different molecular mechanisms and genetic changes occurring in obese women and their association with BC risk and development.

Nanomedicine in therapeutic warfront against estrogen receptor-positive breast cancer

Breast cancer (BC) is the most frequently diagnosed malignancy in women worldwide. Almost 70-80% of cases of BC are curable at the early non-metastatic stage. BC is a heterogeneous disease with different molecular subtypes. Around 70% of breast tumors exhibit estrogen-receptor (ER) expression and endocrine therapy is used for the treatment of these patients. However, there are high chances of recurrence in the endocrine therapy regimen. Though chemotherapy and radiation therapy have substantially improved survival rates and treatment outcomes in BC patients, there is an increased possibility of the development of resistance and dose-limiting toxicities. Conventional treatment approaches often suffer from low bioavailability, adverse effects due to the non-specific action of chemotherapeutics, and low antitumor efficacy. Nanomedicine has emerged as a conspicuous strategy for delivering anticancer therapeutics in BC management. It has revolutionized the area of cancer therapy by increasing the bioavailability of the therapeutics and improving their anticancer efficacy with reduced toxicities on healthy tissues. In this article, we have highlighted various mechanisms and pathways involved in the progression of ER-positive BC. Further, different nanocarriers delivering drugs, genes, and natural therapeutic agents for surmounting BC are the spotlights of this article.

Estrogen/HER2 receptor crosstalk in breast cancer: combination therapies to improve outcomes for patients with hormone receptor-positive/HER2-positive breast cancer

The human epidermal growth factor receptor 2 (HER2) is overexpressed in 13-22% of breast cancers (BC). Approximately 60-70% of HER2+ BC co-express hormone receptors (HRs). HR/HER2 co-expression modulates response to both anti-HER2-directed and endocrine therapy due to "crosstalk" between the estrogen receptor (ER) and HER2 pathways. Combined HER2/ER blockade may be an effective treatment strategy for patients with HR+/HER2+ BC in the appropriate clinical setting(s). In this review, we provide an overview of crosstalk between the ER and HER2 pathways, summarize data from recently published and ongoing clinical trials, and discuss clinical implications for targeted treatment of HR+/HER2+ BC.

2D-CuPd nanozyme overcome tamoxifen resistance in breast cancer by regulating the PI3K/AKT/mTOR pathway

Tamoxifen is the most commonly used treatment for estrogen-receptor (ER) positive breast cancer patients, but its efficacy is severely hampered by resistance. PI3K/AKT/mTOR pathway inhibition was proven to augment the benefit of endocrine therapy and exhibited potential for reversing tamoxifen-induced resistance. However, the vast majority of PI3K inhibitors currently approved for clinical use are unsatisfactory in terms of safety and efficacy. We developed two-dimensional CuPd (2D-CuPd) nanosheets with oxidase and peroxidase nanozyme activities to offer a novel solution to inhibit the activity of the PI3K/AKT/mTOR pathway. 2D-CuPd exhibit superior dual nanozyme activities converting hydrogen peroxide accumulated in drug-resistant cells into more lethal hydroxyl radicals while compensating for the insufficient superoxide anion produced by tamoxifen. The potential clinical utility was further demonstrated in an orthotopically implanted tamoxifen-resistant PDX breast cancer model. Our results reveal a novel nanozyme ROS-mediated protein mechanism for the regulation of the PI3K subunit, illustrate the cellular pathways through which increased p85β protein expression contributes to tamoxifen resistance, and reveal p85β protein as a potential therapeutic target for overcoming tamoxifen resistance. 2D-CuPd is the first reported nanomaterial capable of degrading PI3K subunits, and its high performance combined with further materials engineering may lead to the development of nanozyme-based tumor catalytic therapy.

Statin use in patients with hormone receptor-positive metastatic breast cancer treated with everolimus and exemestane

BACKGROUND

We analyzed the effect of statins in patients with hormone receptor-positive (HR+) metastatic breast cancer treated with everolimus + exemestane (EverX).

MATERIALS AND METHODS

We conducted a nationwide retrospective cohort study using the National Health Insurance database with patients who received EverX for metastatic breast cancer between 2011 and 2019.

RESULTS

Of 224,948 patients diagnosed with breast cancer, 1749 patients who received EverX for at least 30 days were included. Among them, 500 (28.6%) patients were found to take statins with EverX treatment (statin group), and the median duration of this combination was 5.36 months. The median time to treatment duration (TTD) for EverX and the overall survival (OS) were significantly higher in the statin group than in the no-statin group [7.69 vs. 5.06 months, p < 0.001; 45.7 vs. 26.0 months, p < 0.001, respectively]. Multivariable Cox analysis revealed that the use of statins was associated with prolonged TTD [HR = 0.67 (95% CI, 0.59-0.77)] and OS [HR = 0.57 (95% CI, 0.46-0.70)] for EverX even after adjustment for other covariates.

CONCLUSION

Statins may have synergistic effects with endocrine therapy with the mTOR inhibitor everolimus, and improve survival in patients with HR+ metastatic breast cancer.

Plant-derived natural products and combination therapy in liver cancer

Liver cancer is one of the malignant cancers globally and seriously endangers human health because of its high morbidity and mortality. Plant-derived natural products have been evaluated as potential anticancer drugs due to low side effects and high anti-tumor efficacy. However, plant-derived natural products also have defects of poor solubility and cumbersome extraction process. In recent years, a growing numbers of plant derived natural products have been used in combination therapy of liver cancer with conventional chemotherapeutic agents, which has improved clinical efficacy through multiple mechanisms, including inhibition of tumor growth, induction of apoptosis, suppression of angiogenesis, enhancement of immunity, reversal of multiple drug resistance and reduction of side effects. The therapeutic effects and mechanisms of plant-derived natural products and combination therapy on liver cancer are reviewed to provide references for developing anti-liver-cancer strategies with high efficacy and low side effects.

Tocotrienol-Rich Fractions Offer Potential to Suppress Pulmonary Fibrosis Progression

Although pulmonary fibrosis (PF) is considered a rare disease, the incidence thereof has increased steadily in recent years, while a safe and effective cure remains beyond reach. In this study, the potential of tocotrienol-rich fractions (TRF) and carotene to alleviate PF was explored. PF was induced in Sprague-Dawley rats via a single intratracheal bleomycin (BLM) (5 mg/kg) instillation. These rats were subsequently treated with TRF, carotene, pirfenidone (Pir) and nintedanib (Nin) for 28 days via gavage administration, whereafter histopathological performance, biochemical functions and molecular alterations were studied in the lung tissues. Our results showed that TRF, carotene, Nin and Pir all ameliorated PF by reducing inflammation and resisting oxidative stress to varying degrees. The related mechanisms involved the TGF-β1/Smad, PI3K/Akt and NF-κB signaling pathways. Ultimately, our findings revealed that, when combined with TRF, the therapeutic effects of Nin and Pir on PF were enhanced, indicating that TRF may, indeed, provide promising potential for use in combination therapy in the treatment of PF.

Molecular Mechanisms of Anti-Estrogen Therapy Resistance and Novel Targeted Therapies

Breast cancer (BC) is the most commonly diagnosed cancer in women, constituting one-third of all cancers in women, and it is the second leading cause of cancer-related deaths in the United States. Anti-estrogen therapies, such as selective estrogen receptor modulators, significantly improve survival in estrogen receptor-positive (ER+) BC patients, which represents about 70% of cases. However, about 60% of patients inevitably experience intrinsic or acquired resistance to anti-estrogen therapies, representing a major clinical problem that leads to relapse, metastasis, and patient deaths. The resistance mechanisms involve mutations of the direct targets of anti-estrogen therapies, compensatory survival pathways, as well as alterations in the expression of non-coding RNAs (e.g., microRNA) that regulate the activity of survival and signaling pathways. Although cyclin-dependent kinase 4/6 and phosphatidylinositol 3-kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR) inhibitors have significantly improved survival, the efficacy of these therapies alone and in combination with anti-estrogen therapy for advanced ER+ BC, are not curative in advanced and metastatic disease. Therefore, understanding the molecular mechanisms causing treatment resistance is critical for developing highly effective therapies and improving patient survival. This review focuses on the key mechanisms that contribute to anti-estrogen therapy resistance and potential new treatment strategies alone and in combination with anti-estrogen drugs to improve the survival of BC patients.

Predicting clinical response to everolimus in ER+ breast cancers using machine-learning

Endocrine therapy remains the primary treatment choice for ER+ breast cancers. However, most advanced ER+ breast cancers ultimately develop resistance to endocrine. This acquired resistance to endocrine therapy is often driven by the activation of the PI3K/AKT/mTOR signaling pathway. Everolimus, a drug that targets and inhibits the mTOR complex has been shown to improve clinical outcomes in metastatic ER+ breast cancers. However, there are no biomarkers currently available to guide the use of everolimus in the clinic for progressive patients, where multiple therapeutic options are available. Here, we utilized gene expression signatures from 9 ER+ breast cancer cell lines and 23 patients treated with everolimus to develop and validate an integrative machine learning biomarker of mTOR inhibitor response. Our results show that the machine learning biomarker can successfully distinguish responders from non-responders and can be applied to identify patients that will most likely benefit from everolimus treatment.

Targeted therapy for breast cancer: An overview of drug classes and outcomes

The last 25 years have seen significant growth in new therapeutic options for breast cancer, termed targeted therapies based on their ability to block specific pathways known to drive breast tumor growth and survival. Introduction of these drugs has been made possible through advances in the understanding of breast cancer biology. While the promise of targeted therapy for breast cancer has been clear for some time, the experience of the clinical use of multiple drugs and drug classes allows us to now present a summary and perspective as to the success and impact of this endeavor. Here we will review breast cancer targeted therapeutics in clinical use. We will provide the rationale for their indications and summarize clinical data in patients with different breast cancer subtypes, their impact on breast cancer progression and survival and their major adverse effects. The focus of this review will be on the development that has occurred within classes of targeted therapies and subsequent impact on breast cancer patient outcomes. We will conclude with a perspective on the role of targeted therapy in breast cancer treatment and highlight future areas of development.

Estrogen Signaling Dictates Musculoskeletal Stem Cell Behavior: Sex Differences in Tissue Repair

Sexual dimorphisms in humans and other species exist in visually evident features such as body size and less apparent characteristics, including disease prevalence. Current research is adding to a growing understanding of sex differences in stem cell function and response to external stimuli, including sex hormones such as estrogens. These differences are proving significant and directly impact both the understanding of stem cell processes in tissue repair and the clinical implementation of stem cell therapies. Adult stem cells of the musculoskeletal system, including those used for development and repair of muscle, bone, cartilage, fibrocartilage, ligaments, and tendons, are no exception. Both in vitro and in vivo studies have found differences in stem cell number, proliferative and differentiation capabilities, and response to estrogen treatment between males and females of many species. Maintaining the stemness and reducing senescence of adult stem cells is an important topic with implications in regenerative therapy and aging. As such, this review discusses the effect of estrogens on musculoskeletal system stem cell response in multiple species and highlights the research gaps that still need to be addressed. The following evidence from investigations of sex-related phenotypes in adult progenitor and stem cells are pieces to the big puzzle of sex-related effects on aging and disease and critical information for both fundamental tissue repair and regeneration studies and safe and effective clinical use of stem cells. Impact Statement This review summarizes current knowledge of sex differences in and the effects of estrogen treatment on musculoskeletal stem cells in the context of tissue engineering. Specifically, it highlights the impact of sex on musculoskeletal stem cell function and ability to regenerate tissue. Furthermore, it discusses the varying effects of estrogen on stem cell properties, including proliferation and differentiation, important to tissue engineering. This review aims to highlight the potential impact of estrogens and the importance of performing sex comparative studies in the field of tissue engineering.

Nano-Based Theranostic Platforms for Breast Cancer: A Review of Latest Advancements

Breast cancer (BC) is a highly metastatic multifactorial disease with various histological and molecular subtypes. Due to recent advancements, the mortality rate in BC has improved over the past five decades. Detection and treatment of many cancers are now possible due to the application of nanomedicine in clinical practice. Nanomedicine products such as Doxil^® and Abraxane^® have already been extensively used for BC adjuvant therapy with favorable clinical outcomes. However, these products were designed initially for generic anticancer purposes and not specifically for BC treatment. With a better understanding of the molecular biology of BC, several novel and promising nanotherapeutic strategies and devices have been developed in recent years. In this context, multi-functionalized nanostructures are becoming potential carriers for enhanced chemotherapy in BC patients. To design these nanostructures, a wide range of materials, such as proteins, lipids, polymers, and hybrid materials, can be used and tailored for specific purposes against BC. Selective targeting of BC cells results in the activation of programmed cell death in BC cells and can be considered a promising strategy for managing triple-negative BC. Currently, conventional BC screening methods such as mammography, digital breast tomosynthesis (DBT), ultrasonography, and magnetic resonance imaging (MRI) are either costly or expose the user to hazardous radiation that could harm them. Therefore, there is a need for such analytical techniques for detecting BC that are highly selective and sensitive, have a very low detection limit, are durable, biocompatible, and reproducible. In detecting BC biomarkers, nanostructures are used alone or in conjunction with numerous molecules. This review intends to highlight the recent advances in nanomedicine in BC treatment and diagnosis, emphasizing the targeting of BC cells that overexpress receptors of epidermal growth factors. Researchers may gain insight from these strategies to design and develop more tailored nanomedicine for BC to achieve further improvements in cancer specificity, antitumorigenic effects, anti-metastasis effects, and drug resistance reversal effects.

ENDORSE: a prognostic model for endocrine therapy in estrogen-receptor-positive breast cancers

Advanced and metastatic estrogen receptor-positive (ER+ ) breast cancers are often endocrine resistant. However, endocrine therapy remains the primary treatment for all advanced ER+ breast cancers. Treatment options that may benefit resistant cancers, such as add-on drugs that target resistance pathways or switching to chemotherapy, are only available after progression on endocrine therapy. Here we developed an endocrine therapy prognostic model for early and advanced ER+ breast cancers. The endocrine resistance (ENDORSE) model is composed of two components, each based on the empirical cumulative distribution function of ranked expression of gene signatures. These signatures include a feature set associated with long-term survival outcomes on endocrine therapy selected using lasso-regularized Cox regression and a pathway-based curated set of genes expressed in response to estrogen. We extensively validated ENDORSE in multiple ER+ clinical trial datasets and demonstrated superior and consistent performance of the model over clinical covariates, proliferation markers, and multiple published signatures. Finally, genomic and pathway analyses in patient data revealed possible mechanisms that may help develop rational stratification strategies for endocrine-resistant ER+ breast cancer patients.

Expert consensus on the clinical application of PI3K/AKT/mTOR inhibitors in the treatment of advanced breast cancer

Phosphoinositide 3-kinase (PI3K)/protein kinase B (PKB or AKT)/mammalian target of rapamycin (mTOR) signaling pathway (PAM pathway) plays an important role in the development of breast cancer and are closely associated with the resistance to endocrine therapy in advanced breast cancer. Therefore, anticancer treatment targeting key molecules in this signaling pathway has become a research hotspot in recent years. Randomized clinical trials have demonstrated that PI3K/AKT/mTOR inhibitors bring significant clinical benefit to patients with advanced breast cancer, especially to those with hormone receptor (HR)-positive, human epidermal growth factor receptor (HER) 2-negative advanced breast cancer. Alpelisib, a PI3K inhibitor, and everolimus, an mTOR inhibitor, have been approved by FDA. Based on their high efficacy and relatively good safety profile, an expanded indication of everolimus in breast cancer has been approved by National Medical Products Administration (NMPA). Alpelisib is expected to be approved in China in the near future. The members of the consensus expert panel reached this consensus to comprehensively define the role of PI3K/AKT/mTOR signaling pathway in breast cancer, efficacy and clinical applications of PI3K/AKT/mTOR inhibitors, management of adverse reactions, and PIK3CA mutation detection, to promote the understanding of PI3K/AKT/mTOR inhibitors for Chinese oncologists, improve clinical decision-making, and prolong the survival of target patient population.

Muscarinic Receptors Associated with Cancer

Simple Summary

Recently, cancer research has described the presence of the cholinergic machinery, specifically muscarinic receptors, in a wide variety of cancers due to their activation and signaling pathways associated with tumor progression and metastasis, providing a wide overview of their contribution to different cancer formation and development for new antitumor targets. This review focused on determining the molecular signatures associated with muscarinic receptors in breast and other cancers and the need for pharmacological, molecular, biochemical, technological, and clinical approaches to improve new therapeutic targets.

Abstract

Cancer has been considered the pathology of the century and factors such as the environment may play an important etiological role. The ability of muscarinic agonists to stimulate growth and muscarinic receptor antagonists to inhibit tumor growth has been demonstrated for breast, melanoma, lung, gastric, colon, pancreatic, ovarian, prostate, and brain cancer. This work aimed to study the correlation between epidermal growth factor receptors and cholinergic muscarinic receptors, the survival differences adjusted by the stage clinical factor, and the association between gene expression and immune infiltration level in breast, lung, stomach, colon, liver, prostate, and glioblastoma human cancers. Thus, targeting cholinergic muscarinic receptors appears to be an attractive therapeutic alternative due to the complex signaling pathways involved.

Bu-shen-zhu-yun decoction inhibits granulosa cell apoptosis in rat polycystic ovary syndrome through estrogen receptor α-mediated PI3K/AKT/mTOR pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Bu-shen-zhu-yun decoction (BSZYD) is a traditional chinese herbal prescription is widely used in the treatment of infertility.

AIM OF THE STUDY

We aimed to elucidate the impact of a traditional herbal prescription BSZYD on polycystic ovary syndrome (PCOS).

MATERIALS AND METHODS

The candidate active compounds in BSZYD and their putative targets were investigated by bioinformatics analysis. A deydroepiandrosterone (DHEA)-induced PCOS rat model was then constructed using female Sprague-Dawley (SD) rats. Serum hormone levels were measured by enzyme-linked immunosorbent assay (ELISA). Pathological changes in ovarian tissues were analyzed with hematoxylin and eosin (H&E) staining. The expressions of estrogen receptor α (ER α)-mediated PI3K/AKT/mTOR pathway were measured by immunofluorescence and western blotting.

RESULTS

Bioinformatics analysis showed that the putative targets of active compound candidates in BSZYD were enriched in PI3K/AKT and estrogen signaling pathways related to regulating ovarian ovulation. Animal experiments showed that BSZYD significantly alleviated pathological changes in the ovary, altered hormone levels of serum and reduced apoptosis rate of granulosa cells. In addition, BSZYD treatment notably upregulated the expressions of proteins in ER α-mediated PI3K/AKT/mTOR pathway and downregulated apoptosis-related proteins in PCOS rats.

CONCLUSION

BSZYD can restore ovary lesions and ameliorate apoptosis through ER α-mediated PI3K/AKT/mTOR pathway, which might partly contribute to the treatment of PCOS.

Anticancer activity of chicken cathelicidin peptides against different types of cancer

BACKGROUND

This study served as the pioneer in studying the anti-cancer role of chicken cathelicidin peptides.

METHODS AND RESULTS

Chicken cathelicidins were used as anticancer agent against the breast cancer cell line (MCF-7) and human colon cancer cell line (HCT116). In addition, the mechanism of action of the interaction of cationic peptides with breast cancer cell line MCF-7 was also investigated. An in vivo investigation was also achieved to evaluate the role of chicken cathelicidin in Ehrlich ascites cell (EAC) suppression as a tumor model after subcutaneous implantation in mice. It was found during the study that exposure of cell lines to 40 µg/ml of chicken cathelicidin for 72 h reduced cell lines growth rate by 90-95%. These peptides demonstrated down-regulation of (cyclin A1 and cyclin D genes) of MCF-7 cells. The study showed that two- and three-fold expression of both of caspase-3 and - 7 genes in untreated MCF-7 cells compared to treated MCF-7 cells with chicken cathelicidin peptides. Our data showed that chicken (CATH-1) enhance releasing of TNFα, INF-γ and upregulation of granzyme K in treated mice groups, in parallel, the tumor size and volume was reduced in the treated EAC-bearing groups. Tumor of mice groups treated with chicken cathelicidin displayed high area of necrosis compared to untreated EAC-bearing mice. Based on histological analysis and immunohistochemical staining revealed that the tumor section in Ehrlich solid tumor exhibited a strong Bcl2 expression in untreated control compared to mice treated with 10 & 20 µg of cathelicidin. Interestingly, low expression of Bcl2 were observed in mice taken 40 µg/mL of CATH-1.

CONCLUSIONS

This study drive intention in treatment of cancer through the efficacy of anticancer efficacy of chicken cathelicidin peptides.

m6A binding protein YTHDF2 in cancer

YT521-B homology domain family member 2 (YTHDF2) is an N⁶-methyladenosine (m⁶A)-binding protein that was originally found to regulate the stability of mRNA. Growing evidence has shown that YTHDF2 can participate in multifarious bioprocesses, including embryonic development, immune response, and tumor progression. Furthermore, YTHDF2 is closely associated with the proliferation, apoptosis, invasion, and migration of tumor cells, suggesting its significant role in cancers. YTHDF2 primarily relies on m⁶A modification to modulate signaling pathways in cancer cells. However, the expression and function of YTHDF2 in human malignancies remain controversial. Meanwhile, the underlying molecular mechanisms of YTHDF2 have not been elucidated. In this review, we principally summarized the biological functions and molecular mechanisms of YTHDF2 in tumors and discussed its prognostic and therapeutic values.

The Role of mTOR and eIF Signaling in Benign Endometrial Diseases

Adenomyosis, endometriosis, endometritis, and typical endometrial hyperplasia are common non-cancerous diseases of the endometrium that afflict many women with life-impacting consequences. The mammalian target of the rapamycin (mTOR) pathway interacts with estrogen signaling and is known to be dysregulated in endometrial cancer. Based on this knowledge, we attempt to investigate the role of mTOR signaling in benign endometrial diseases while focusing on how the interplay between mTOR and eukaryotic translation initiation factors (eIFs) affects their development. In fact, mTOR overactivity is apparent in adenomyosis, endometriosis, and typical endometrial hyperplasia, where it promotes endometrial cell proliferation and invasiveness. Recent data show aberrant expression of various components of the mTOR pathway in both eutopic and ectopic endometrium of patients with adenomyosis or endometriosis and in hyperplastic endometrium as well. Moreover, studies on endometritis show that derangement of mTOR signaling is linked to the establishment of endometrial dysfunction caused by chronic inflammation. This review shows that inhibition of the mTOR pathway has a promising therapeutic effect in benign endometrial conditions, concluding that mTOR signaling dysregulation plays a critical part in their pathogenesis.

Systematic understanding of anti-tumor mechanisms of Tamarixetin through network and experimental analyses

Tamarixetin, a flavonoid derived from Quercetin, was shown to possess anti-cancer properties in various types of cancer. However, the mechanism of action of this compound is not well understood. Observations from reverse docking and network pharmacology analysis, were validated by cell based studies to analyse the chemotherapeutic potential and elucidate the molecular mechanism of action of Tamarixetin in breast cancer. In silico analysis using reverse docking and PPI analysis clearly indicated that out of 35 proteins targeted by Tamarixetin, the top 3 hub genes, namely, AKT1, ESR1 and HSP90AA1, were upregulated in breast tumor tissues and more importantly showed strong negative correlation to breast cancer patient survival. Furthermore, the KEGG pathway analysis showed enrichment of target proteins of Tamarixetin in 33 pathways which are mainly involved in neoplastic signalling. In vitro cell-based studies demonstrated that Tamarixetin could inhibit cell proliferation, induce ROS and reduce mitochondrial membrane potential, leading to cell death. Tamarixetin induced cell cycle arrest at G2/M phase and inhibited the migration as well as the invasion of breast cancer cells. Taken together, the combination of in silico and in vitro approaches used in the present study clearly provides evidence for the chemotherapeutic potential of Tamarixetin in breast cancer.

Factors influencing the anticancer effects of metformin on breast cancer outcomes: a systematic review and meta-analysis

INTRODUCTION

Several clinical trials have attempted to find evidence that supports the use of metformin as an anticancer treatment. However, the observed effects on various breast cancer (BC) outcomes have been heterogeneous.

AREAS COVERED

Based on the outcomes of previous clinical trials, this review discusses the patients' characteristics, cancer intrinsic subtypes, cancer stage, and anticancer treatments that may influence the anticancer effect of metformin on BC outcomes. Additionally, the safety and tolerability of metformin addition to various anticancer regimens are reviewed.

EXPERT OPINION

Metformin is a challenging anticancer agent in BC cohorts, besides being safe and well-tolerated at antidiabetic doses. Survival benefits of metformin have been observed in BC patients with: hormone receptor-positive, human epidermal growth factor receptor-2 overexpression, and high insulin like growth factor-1 receptor expression on the tumor surface. Moreover, patients with diabetes receiving metformin experienced better survival outcomes compared to diabetic patients not receiving metformin. Additionally, metformin has anti-proliferative activity in patients with BC who have high insulin resistance and high body mass index. Besides, metformin has been shown to decrease metastatic events, and enhance the level of metabolic- and insulin-related biomarkers associated with carcinogenesis. Finally, most adverse events following metformin treatment were low-grade GIT toxicities.

MUC1 is a potential target to overcome trastuzumab resistance in breast cancer therapy

Although resistance is its major obstacle in cancer therapy, trastuzumab is the most successful agent in treating epidermal growth factor receptor 2 positive (HER2 +) breast cancer (BC). Some patients show resistance to trastuzumab, and scientists want to circumvent this problem. This review elaborately discusses possible resistance mechanisms to trastuzumab and introduces mucin 1 (MUC1) as a potential target efficient for overcoming such resistance. MUC1 belongs to the mucin family, playing the oncogenic/mitogenic roles in cancer cells and interacting with several other oncogenic receptors and pathways, such as HER2, β-catenin, NF-κB, and estrogen receptor (ERα). Besides, it has been established that MUC1- Cytoplasmic Domain (MUC1-CD) accelerates the development of resistance to trastuzumab and that silencing MUC1-C proto-oncogene is associated with increased sensitivity of HER2⁺ cells to trastuzumab-induced growth inhibitors. We mention why targeting MUC1 can be useful in overcoming trastuzumab resistance in cancer therapy.

Potential “Therapeutic” Effects of Tocotrienol-Rich Fraction (TRF) and Carotene “Against” Bleomycin-Induced Pulmonary Fibrosis in Rats via TGF-β/Smad, PI3K/Akt/mTOR and NF-κB Signaling Pathways

Background: Pulmonary fibrosis (PF) is a chronic, progressive, and, ultimately, terminal interstitial disease caused by a variety of factors, ranging from genetics, bacterial, and viral infections, to drugs and other influences. Varying degrees of PF and its rapid progress have been widely reported in post-COVID-19 patients and there is consequently an urgent need to develop an appropriate, cost-effective approach for the prevention and management of PF. Aim: The potential “therapeutic” effect of the tocotrienol-rich fraction (TRF) and carotene against bleomycin (BLM)-induced lung fibrosis was investigated in rats via the modulation of TGF-β/Smad, PI3K/Akt/mTOR, and NF-κB signaling pathways. Design/Methods: Lung fibrosis was induced in Sprague-Dawley rats by a single intratracheal BLM (5 mg/kg) injection. These rats were subsequently treated with TRF (50, 100, and 200 mg/kg body wt/day), carotene (10 mg/kg body wt/day), or a combination of TRF (200 mg/kg body wt/day) and carotene (10 mg/kg body wt/day) for 28 days by gavage administration. A group of normal rats was provided with saline as a substitute for BLM as the control. Lung function and biochemical, histopathological, and molecular alterations were studied in the lung tissues. Results: Both the TRF and carotene treatments were found to significantly restore the BLM-induced alterations in anti-inflammatory and antioxidant functions. The treatments appeared to show pneumoprotective effects through the upregulation of antioxidant status, downregulation of MMP-7 and inflammatory cytokine expressions, and reduction in collagen accumulation (hydroxyproline). We demonstrated that TRF and carotene ameliorate BLM-induced lung injuries through the inhibition of apoptosis, the induction of TGF-β1/Smad, PI3K/Akt/mTOR, and NF-κB signaling pathways. Furthermore, the increased expression levels were shown to be significantly and dose-dependently downregulated by TRF (50, 100, and 200 mg/kg body wt/day) treatment in high probability. The histopathological findings further confirmed that the TRF and carotene treatments had significantly attenuated the BLM-induced lung injury in rats. Conclusion: The results of this study clearly indicate the ability of TRF and carotene to restore the antioxidant system and to inhibit proinflammatory cytokines. These findings, thus, revealed the potential of TRF and carotene as preventive candidates for the treatment of PF in the future.

A Low Dose Combination of Withaferin A and Caffeic Acid Phenethyl Ester Possesses Anti-Metastatic Potential In Vitro: Molecular Targets and Mechanisms

Simple Summary

Cancer therapy suffers from its high cost and high rate of adverse effects and relapse of the disease. Hence, the new (preferably natural), economic and safer therapeutic as well preventive measures have been on demand and have been subject of priority research. We have, earlier, demonstrated anticancer activity in the extracts of Ashwagandha leaves and propolis. A combination of Wi-A (an active anticancer ingredient in Ashwagandha extract) and CAPE (an active anticancer ingredient in propolis) was earlier shown to offer higher and cancer cell-selective cytotoxicity. In the present study, we report an anti-metastasis activity in the low dose combination of Wi-A and CAPE along with its mechanism of action and propose its use in cancer metastasis treatment.

Abstract

Withaferin A (Wi-A) and Caffeic Acid Phenethyl Ester (CAPE) are the bioactive ingredients of Ashwagandha (Withania somnifera) and propolis, respectively. Both of these natural compounds have been shown to possess anticancer activity. In the present study, we recruited a low dose of each of these compounds and developed a combination that exhibited remarkably potent anti-migratory and anti-angiogenic activities. Extensive molecular analyses including a cDNA array and expression analyses of the specific gene targets demonstrated that such activities are mediated through their effect on cell adhesion/tight junction proteins (Claudins, E-cadherin), inhibition of canonical Wnt/β-catenin signaling pathways and the consequent downregulation of EMT-signaling proteins (Vimentin, MMPs, VEGF and VEGFR) that play a critical role in cancer metastasis. The data supported that this novel combination of Wi-A and CAPE (Wi-ACAPE, containing 0.5 µM of Wi-A and 10 µM of CAPE) may be recruited for the treatment of metastatic and aggressive cancers and, hence, warrant further evaluation by recruiting a variety of experimental and clinical metastatic models.

The natural isoflavone Biochanin-A synergizes 5-fluorouracil anticancer activity in vitro and in vivo in Ehrlich solid-phase carcinoma model

Isoflavones are considered one of the most extensively studied plant-derived phytoestrogenic compounds. Of these, Biochanin A (Bio-A), a natural isoflavone abundant in cabbage, alfalfa, and red clover, has drawn a lot of attention. As reported in multiple studies, Bio-A possesses a promising anticancer activity against estrogen receptor-positive (ER+)  breast cancer. The current study investigated the working hypothesis that Bio-A could synergistically enhance the potency of 5-fluorouracil (5-FU) in ER+ breast cancer. The hypothesis was tested both in vitro on hormone receptor-positive (MCF-7) and triple-negative breast cancer cells (MDA-MB231). Additionally, in vivo studies were performed in the Ehrlich solid-phase carcinoma mouse model. The in vitro cytotoxicity studies revealed that Bio-A synergistically increased the potency of 5-FU in both MCF-7 and MDA-MB231 cell lines. The synergistic effect of 5-FU/Bio-A combination was verified in vivo. The combination therapy (where 5-FU was used at one fourth its full dose) led to a significant 75% reduction in tumor volume after two treatment cycles. This was in addition to producing a significant 2.1-fold increase in tumor necrosis area% compared to mock-treated control. In conclusion, the current study presents the first preclinical evidence for the potential merit of 5-FU/Bio-A combination for the treatment of ER+ breast cancer. The synergistic antitumor effect of Bio-A/ 5-FU combination can be, at least partly, attributed to Bio-A-mediated suppression of ER-α/Akt axis and the augmentation of 5-FU-mediated proapoptotic effects. © 2022 John Wiley & Sons, Ltd.

In silico docking and ADME study of deketene curcumin derivatives (DKC) as an aromatase inhibitor or antagonist to the estrogen-alpha positive receptor (Erα+): potent application of breast cancer

Regardless of many extensive studies, hormonal-based breast cancer is the most common cause of cancer-related mortality of females worldwide. Indeed, estrogen receptor-positive (ER +) is the communal subtype in breast cancer. To treat this, three types of medications are typically used: selective estrogen receptor modulators (SERMs), selective estrogen receptor down modulators (SERDMs), and aromatase inhibitors (AIs), all of which directly interact with the activation of the estrogen signaling pathway and its formation. Despite their effectiveness, the development of new treatments is required since clinical efficacy is restricted owing to resistance. As a result, in silico studies for drug discovery are booming over the decades because of their affordability and less time-consuming features. Here, 25 deketene curcumin derivatives have been selected for docking studies through MVD software over the positive type of breast cancer through both the treatment hosts Erα + receptor and aromatase. DKC compounds are used because they have several pharmacological uses, including anti-cancer, anti-diabetic, anti-viral, anti-fungal, and anti-bacterial properties. Moreover, an ADME study was carried out for DKC derivatives that reveal the optimum drug-likeness profile. From 25 derivatives, the results showed a better MolDock score, hydrogen bonding, and steric interaction between compounds DKC-10, DKC-20, and DKC-21 with Erα + and aromatase. Although the study was done on both the treatable path hosts, better results were obtained with Erα + as an antagonist. Therefore, it is proposed that three selected DKC derivatives would be better therapeutic agents against breast cancer.

Identification of Prognostic Biomarkers for Glioblastoma Based on Transcriptome and Proteome Association Analysis

Objective:

Glioblastoma multiforme (GBM) is the most malignant primary brain tumor in adults. This study aimed to identify significant prognostic biomarkers related to GBM.

Methods:

We collected 3 GBM and 3 healthy human brain samples for transcriptome and proteomic sequencing analysis. Differentially expressed genes (DEGs) between GBM and control samples were identified using the edge R package in R. Functional enrichment analyses, prediction of long noncoding RNA target genes, and protein-protein interaction network analyses were performed. Subsequently, transcriptomic and proteomic association analyses, validation using The Cancer Genome Atlas (TCGA) database, and survival and prognostic analyses were conducted. Then the hub genes directly related to GBM were screened. Finally, the expression of key genes was verified by quantitative polymerase chain reaction (qPCR).

Results:

Totally, 1140 transcripts and 503 proteins were significantly up- or down-regulated. A total of 25 genes were upregulated and 62 were downregulated at both the transcriptome and proteome levels. Results from TCGA database showed that 84 of these 87 genes matched with transcriptome sequencing results. A Cox regression analysis suggested that Fibronectin 1(FN1) was a prognostic risk factor. The qPCR results showed that FN1 was significantly upregulated in GBM samples.

Conclusions:

FN1 may play a role in GBM progression through ECM-receptor interaction and PI3K-Akt signaling pathways. FN1 may be considered as a prognostic biomarkers related to GBM.

Sea Cucumber Intestinal Peptide Induces the Apoptosis of MCF-7 Cells by Inhibiting PI3K/AKT Pathway

Sea cucumbers are one of many marine echinoderm animals that contain valuable nutrients and medicinal compounds. The bioactive substances in sea cucumbers make them have promising biological and pharmacological properties, including antioxidant, anti-bacterial, and anti-tumor effects. In this study, sea cucumber intestinal peptide (SCIP) is a small molecular oligopeptide (<1,000 Da) extracted from sea cucumber intestines hydrolyzed by alkaline protease. The analysis of amino acid composition showed that hydrophobic amino acids and branched-chain amino acids were rich in SCIP. Nowadays, although increasing studies have revealed the biological functions of the sea cucumber active substances, there are few studies on the function of SCIP. Furthermore, due to the anti-cancer activity being an essential characteristic of sea cucumber active substances, we also investigated the anti-cancer potential and the underlying mechanism of SCIP in vivo and in vitro. The results indicate that SCIP inhibits the growth of MCF-7 tumor cells in zebrafish and increases the apoptosis of human breast cancer MCF-7 cells. Further mechanism studies confirm that SCIP promotes the expression of apoptosis-related proteins and thus promotes the breast cancer cells (MCF-7) apoptosis via inhibition of PI3K/AKT signal transduction pathway.

Global signalling network analysis of luminal T47D breast cancer cells in response to progesterone

BACKGROUND

Breast cancer cells enter into the cell cycle following progestin exposure by the activation of signalling cascades involving a plethora of enzymes, transcription factors and co-factors that transmit the external signal from the cell membrane to chromatin, ultimately leading to a change of the gene expression program. Although many of the events within the signalling network have been described in isolation, how they globally team up to generate the final cell response is unclear.

METHODS

In this study we used antibody microarrays and phosphoproteomics to reveal a dynamic global signalling map that reveals new key regulated proteins and phosphor-sites and links between previously known and novel pathways. T47D breast cancer cells were used, and phospho-sites and pathways highlighted were validated using specific antibodies and phenotypic assays. Bioinformatic analysis revealed an enrichment in novel signalling pathways, a coordinated response between cellular compartments and protein complexes.

RESULTS

Detailed analysis of the data revealed intriguing changes in protein complexes involved in nuclear structure, epithelial to mesenchyme transition (EMT), cell adhesion, as well as transcription factors previously not associated with breast cancer cell proliferation. Pathway analysis confirmed the key role of the MAPK signalling cascade following progesterone and additional hormone regulated phospho-sites were identified. Full network analysis shows the activation of new signalling pathways previously not associated with progesterone signalling in T47D breast cancer cells such as ERBB and TRK. As different post-translational modifications can mediate complex crosstalk mechanisms and massive PARylation is also rapidly induced by progestins, we provide details of important chromatin regulatory complexes containing both phosphorylated and PARylated proteins.

CONCLUSIONS

This study contributes an important resource for the scientific community, as it identifies novel players and connections meaningful for breast cancer cell biology and potentially relevant for cancer management.

Anticancer effects of veratramine via the phosphatidylinositol-3-kinase/serine-threonine kinase/mechanistic target of rapamycin and its downstream signaling pathways in human glioblastoma cell lines

AIMS

Antitumor effects of veratramine in prostate and liver cancers has been investigated, but it is still unclear whether veratramine can be used as an effective therapeutic agent for glioma. The aim of this study was to evaluate the potential pharmacological mechanism of veratramine in glioma.

MAIN METHODS

Using four types of human glioblastoma cell lines, including A172, HS-683, T98G, and U-373-MG the dose-dependent antitumor effect of veratramine was evaluated. The cytotoxicity and cell proliferation were examined by CCK-8, and cell proliferation was further confirmed by anchorage-independent colony formation assay. The cell cycle distribution and apoptotic rate was assessed by flow cytometry, and apoptosis was further evaluated by apoptosis assay. The migration and invasiveness capacity were analyzed by using transwell. Protein and mRNA levels of related factors were determined by western blotting and RT-qPCR, respectively.

KEY FINDINGS

Veratramine markedly induced apoptosis, suppressed the cell proliferation via the cell cycle G₀/G₁ phase arrest, and reduced the capacity for the migration and invasion in human glioblastoma multiforme cell lines. Moreover, veratramine was sufficient to affect the phosphatidylinositol-3-kinase/serine-threonine kinase/mechanistic target of rapamycin signaling pathway and its downstream Mdm2/p53/p21 pathway in human glioblastoma cell lines.

SIGNIFICANCE

Antitumor effects of veratramine in suppression of glioma progression was mediated by the regulation of PI3K/Akt/mTOR and Mdm2/p53/p21 signaling pathway.

Targeting AKT in ER-Positive HER2-Negative Metastatic Breast Cancer: From Molecular Promises to Real Life Pitfalls?

The AKT protein kinase plays a central role in several interconnected molecular pathways involved in growth, apoptosis, angiogenesis, and cell metabolism. It thereby represents a therapeutic target, especially in hormone receptor-positive (HR) breast cancers, where the PI3K/AKT signaling pathway is largely hyperactivated. Moreover, resistance to therapeutic classes, including endocrine therapy, is associated with the constitutive activation of the PI3K/AKT pathway. Improved knowledge on the molecular mechanisms underlying resistance to endocrine therapy has led to the diversification of the therapeutic arsenal, notably with the development of PI3K and mTOR inhibitors, which are currently approved for the treatment of advanced HR-positive breast cancer patients. AKT itself constitutes a novel pharmacological target for which AKT inhibitors have been developed and tested in clinical trials. However, despite its pivotal role in cell survival and anti-apoptotic mechanisms, as well as in endocrine therapy resistance, few drugs have been developed and are available for clinical practice. The scope of the present review is to focus on the pivotal role of AKT in metastatic breast cancer through the analysis of its molecular features and to discuss clinical implications and remaining challenges in the treatment of HR-positive metastatic breast cancer.