Inhibition of Stat3 Signaling Pathway by Natural Product Pectolinarigenin Attenuates Breast Cancer Metastasis

Potential therapeutic targets of the JAK2/STAT3 signaling pathway in triple-negative breast cancer

Triple-negative breast cancer (TNBC) poses a significant clinical challenge due to its propensity for metastasis and poor prognosis. TNBC evades the body's immune system recognition and attack through various mechanisms, including the Janus Kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) signaling pathway. This pathway, characterized by heightened activity in numerous solid tumors, exhibits pronounced activation in specific TNBC subtypes. Consequently, targeting the JAK2/STAT3 signaling pathway emerges as a promising and precise therapeutic strategy for TNBC. The signal transduction cascade of the JAK2/STAT3 pathway predominantly involves receptor tyrosine kinases, the tyrosine kinase JAK2, and the transcription factor STAT3. Ongoing preclinical studies and clinical research are actively investigating this pathway as a potential therapeutic target for TNBC treatment. This article comprehensively reviews preclinical and clinical investigations into TNBC treatment by targeting the JAK2/STAT3 signaling pathway using small molecule compounds. The review explores the role of the JAK2/STAT3 pathway in TNBC therapeutics, evaluating the benefits and limitations of active inhibitors and proteolysis-targeting chimeras in TNBC treatment. The aim is to facilitate the development of novel small-molecule compounds that target TNBC effectively. Ultimately, this work seeks to contribute to enhancing therapeutic efficacy for patients with TNBC.

Niclosamide - encapsulated lipid nanoparticles for the reversal of pulmonary fibrosis

Pulmonary fibrosis (PF) is a serious and progressive fibrotic interstitial lung disease that is possibly life-threatening and that is characterized by fibroblast accumulation and collagen deposition. Nintedanib and pirfenidone are currently the only two FDA-approved oral medicines for PF. Some drugs such as antihelminthic drug niclosamide (Ncl) have shown promising therapeutic potentials for PF treatment. Unfortunately, poor aqueous solubility problems obstruct clinical application of these drugs. Herein, we prepared Ncl-encapsulated lipid nanoparticles (Ncl-Lips) for pulmonary fibrosis therapy. A mouse model of pulmonary fibrosis induced by bleomycin (BLM) was generated to assess the effects of Ncl-Lips and the mechanisms of reversing fibrosis in vivo. Moreover, cell models treated with transforming growth factor β1 (TGFβ1) were used to investigate the mechanism through which Ncl-Lips inhibit fibrosis in vitro. These findings demonstrated that Ncl-Lips could alleviate fibrosis, consequently reversing the changes in the levels of the associated marker. Moreover, the results of the tissue distribution experiment showed that Ncl-Lips had aggregated in the lung. Additionally, Ncl-Lips improved the immune microenvironment in pulmonary fibrosis induced by BLM. Furthermore, Ncl-Lips suppressed the TGFβ1-induced activation of fibroblasts and epithelial-mesenchymal transition (EMT) in epithelial cells. Based on these results, we demonstrated that Ncl-Lips is an efficient strategy for reversing pulmonary fibrosis via drug-delivery.

Mechanisms of Traditional Chinese medicine/natural medicine in HR-positive Breast Cancer: A comprehensive Literature Review

ETHNOPHARMACOLOGICAL RELEVANCE

With the emergence of endocrine resistance, the survival and good prognosis of HR-positive breast cancer (HR + BC) patients are threatened. As a common complementary and alternative therapy in cancer treatment, traditional Chinese medicine (TCM) has been widely used, and its internal mechanisms have been increasingly explored.

AIM OF THE REVIEW

In this review, the development status and achievements in understanding of the mechanisms related to the anti-invasion and anti-metastasis effects of TCM against HR + BC and the reversal of endocrine drug resistance by TCM in recent years have been summarized to provide ideas for antitumour research on the active components of TCM/natural medicine.

METHODS

We searched the electronic databases PubMed, Web of Science, and China National Knowledge Infrastructure database (CNKI) (from inception to July 2023) with the key words "HR-positive breast cancer" or "HR-positive breast carcinoma", "HR + BC" and "traditional Chinese medicine", "TCM", or "natural plant", "herb", etc., with the aim of elucidating the intrinsic mechanisms of traditional Chinese medicine and natural medicine in the treatment of HR + BC.

RESULTS

TCM/natural medicine monomers and formulas can regulate the expression of related genes and proteins through the PI3K/AKT, JAK2/STAT3, MAPK, Wnt and other signalling pathways, inhibit the proliferation and metastasis of HR + BC tumours, play a synergistic role in combination with endocrine drugs, and reverse endocrine drug resistance.

CONCLUSION

The wide variety of TCM/natural medicine components makes the research and development of new methods of TCM for BC treatments more selective and innovative. Although progress has been made on research on TCM/natural medicine, there are still many problems in clinical and basic experimental designs, and more in-depth scientific explorations and research are still needed.

Pectolinarigenin attenuates hepatic ischemia/reperfusion injury via activation of the PI3K/AKT/Nrf2 signaling pathway

Hepatic ischemia/reperfusion (I/R) injury is an unavoidable complication of liver hepatectomy, transplantation, and systemic shock. Pectolinarigenin (Pec) is a flavonoid with many biological activities, which include anti-inflammatory, anti-apoptotic, and antioxidant stress. This study explored whether Pec pretreatment could reduce hepatic I/R injury and the potential mechanisms at play. After pretreatment of mice and AML12 cells with Pec, I/R and hypoxia/reoxygenation (H/R) models were established. By examining markers related to liver injury, cell viability, oxidative stress, inflammatory response, and apoptosis, the effect of Pec on important processes involved in hepatic I/R injury was assessed. Protein levels associated with the PI3K/AKT/Nrf2 pathway were analyzed by relative quantification to investigate possible pathways through which Pec plays a role in the I/R process. Pec treatment corrected abnormal transaminase levels resulting from I/R injury, improved liver injury, and increased AML12 cell viability. Moreover, Pec treatment inhibited oxidative stress, inflammation and apoptosis and could activate the PI3K/AKT/Nrf2 pathway during I/R and H/R. Further studies found that LY294002 (PI3K inhibitor) suppressed the protective effect of Pec on hepatic I/R injury. In summary, our results show that Pec inhibits oxidative stress, inflammatory responses, and apoptosis, thereby attenuating I/R-induced liver injury and H/R-induced cell damage via activation of the PI3K/AKT/Nrf2 pathway.

Bufotalin Suppresses Proliferation and Metastasis of Triple-Negative Breast Cancer Cells by Promoting Apoptosis and Inhibiting the STAT3/EMT Axis

Triple-negative breast cancer (TNBC) is a highly aggressive type of breast cancer and has a poor prognosis. As standardized TNBC treatment regimens cause drug resistance and tumor recurrence, the development of new TNBC treatment strategies is urgently required. Bufotalin is a bufadienolide isolated from the skin and parotid venom glands of the toad Bufo gargarizan, and has several pharmacological properties, including antiviral, anti-inflammatory, and anticancer activities. However, the anticancer effect and underlying molecular mechanisms of action of bufotalin in TNBC have not been fully studied. In the current study, we investigated the effects of bufotalin on the growth and metastasis of MDA-MB-231 and HCC1937 TNBC cells. Bufotalin potently inhibited the proliferation of both TNBC cell lines by promoting cell cycle arrest and caspase-mediated apoptosis. Furthermore, bufotalin effectively suppressed the migration and invasion of both TNBC cell lines by regulating the expression of key epithelial-mesenchymal transition (EMT) biomarkers, matrix metalloproteinases (MMPs), and integrin α6. Notably, the anticancer effect of bufotalin in TNBC cells was associated with the downregulation of the signal transducer and activator of the transcription 3 (STAT3) signaling pathway. Collectively, our results suggest that the natural compound bufotalin may exert antiproliferative and antimetastatic activities in TNBC cells by modulating the apoptotic pathway and the STAT3/EMT axis.

Pectolinarigenin inhibits bladder urothelial carcinoma cell proliferation by regulating DNA damage/autophagy pathways

Pectolinarigenin (PEC), an active compound isolated from traditional herbal medicine, has shown potential anti-tumor properties against various types of cancer cells. However, its mechanism of action in bladder cancer (BLCA), which is one of the fatal human carcinomas, remains unexplored. In this study, we first revealed that PEC, as a potential DNA topoisomerase II alpha (TOP2A) poison, can target TOP2A and cause significant DNA damage. PEC induced G2/M phase cell cycle arrest via p53 pathway. Simultaneously, PEC can perform its unique function by inhibiting the late autophagic flux. The blocking of autophagy caused proliferation inhibition of BLCA and further enhanced the DNA damage effect of PEC. In addition, we proved that PEC could intensify the cytotoxic effect of gemcitabine (GEM) on BLCA cells in vivo and in vitro. Summarily, we first systematically revealed that PEC had great potential as a novel TOP2A poison and an inhibitor of late autophagic flux in treating BLCA.

Pectolinarigenin alleviated septic acute kidney injury via inhibiting Jak2/Stat3 signaling and mitochondria dysfunction

Sepsis is a systemic inflammatory response to infection, where sepsis-associated acute kidney injury (AKI) is a common morbid disease with a high morbidity and mortality, and however at present no effective therapy exists. Increasing evidence have shown that mitochondrial damage and inflammatory response are important initiating factors in pathogenesis of septic AKI. Natural flavonoid pectolinarigenin exerted anti-inflammatory properties in previous studies, while its role in septic AKI remains unknown. In the study, pectolinarigenin administration significantly ameliorated the dramatic rise of serum creatinine and blood urea nitrogen in lipopolysaccharide (LPS)- and cecal ligation/puncture (CLP)-induced septic mice, respectively. Consistently, LPS/CLP-induced renal damage as implied by histopathological score and the increased injury markers NGAL and KIM-1, which was attenuated by pectolinarigenin. Meanwhile, LPS/CLP triggered proinflammatory cytokine production and inflammation related proteins in the kidneys. However, pectolinarigenin inhibited renal expression of IL-6, IL-1β, TNF-α, and MCP-1 to improve inflammatory response. Furthermore, pectolinarigenin upregulated Bcl-2 protein expression and suppressed apoptotic protein of BAX and cleaved caspase-3 in the kidneys of CLP-induced septic AKI. Mechanistically, LPS could induce the high expression of IL-6 and trigger the phosphorylation of Jak2 and Stat3, while pectolinarigenin remarkably reduced their corresponding levels. Notably, CLP-induced kidney injury of mice significantly reduced the expression of PGC-1α, OPA1 and increased the expression of Drp1, Cyt-C, where pectolinarigenin pretreatment significantly restored their corresponding expression in mice. In summary, pectolinarigenin improved septic AKI via inhibiting JAK2/STAT3 signaling and mitochondria dysfunction.

STAT family of transcription factors in breast cancer: Pathogenesis and therapeutic opportunities and challenges

Breast cancer is the most commonly diagnosed cancer and second-leading cause of cancer deaths in women. Breast cancer stem cells (BCSCs) promote metastasis and therapeutic resistance contributing to tumor relapse. Through activating genes important for BCSCs, transcription factors contribute to breast cancer metastasis and therapeutic resistance, including the signal transducer and activator of transcription (STAT) family of transcription factors. The STAT family consists of six major isoforms, STAT1, STAT2, STAT3, STAT4, STAT5, and STAT6. Canonical STAT signaling is activated by the binding of an extracellular ligand to a cell-surface receptor followed by STAT phosphorylation, leading to STAT nuclear translocation and transactivation of target genes. It is important to note that STAT transcription factors exhibit diverse effects in breast cancer; some are either pro- or anti-tumorigenic while others maintain dual, context-dependent roles. Among the STAT transcription factors, STAT3 is the most widely studied STAT protein in breast cancer for its critical roles in promoting BCSCs, breast cancer cell proliferation, invasion, angiogenesis, metastasis, and immune evasion. Consequently, there have been substantial efforts in developing cancer therapeutics to target breast cancer with dysregulated STAT3 signaling. In this comprehensive review, we will summarize the diverse roles that each STAT family member plays in breast cancer pathobiology, as well as, the opportunities and challenges in pharmacologically targeting STAT proteins and their upstream activators in the context of breast cancer treatment.

Investigation of molecular mechanisms underlying JAK/STAT signaling pathway in HPV-induced cervical carcinogenesis using 'omics' approach

The precise mechanism of action of Janus Kinases (JAK)/Signal Transducer and activator of Transcription (STAT) signaling in human papillomavirus (HPV)-associated cervical cancer (CaCx) is poorly defined. The present study dissected the underlying components of JAK/STAT signaling in HPV-positive cervical neoplasms. Whole transcriptome profile of CaCx cohort from TCGA database revealed elevated STAT3 and its impact on CaCx patients' survival. Using the RT² Profiler PCR Array, we analyzed 84 genes of interest associated with JAK/STAT signaling in mRNA derived from HPV-negative and HPV-positive cervical lesions which revealed 21 differentially expressed genes (DEGs). Analyses of DEGs using the Database for Annotation, Visualization and Integrated Discovery tool indicated maximum genes enriched in immune response and negative regulation of apoptotic process. Protein-protein network analysis indicated IL4, STAT5A, STAT4, and JAK3 to be the key genes in the interaction network. Further, 7 key DEGs (IL4R, IRF1, EGFR, OAS1, PIAS1, STAT4, and STAT5A) were validated in TCGA cohort using R2 platform. These genes were differentially expressed among HPV-positive cervical tissues and their correlation with STAT3 was established. EGFR and IL4R showed a comparatively strong correlation with STAT3 that supports their involvement in pathogenesis of CaCx. Finally, the Kaplan-Meier analysis established the prognostic association of the key DEGs, in CaCx cohort. The STAT3 and associated key genes discovered from our study establish a strong pathogenic role of JAK/STAT3 pathway in HPV-mediated cervical carcinogenesis.

PIM1/STAT3 axis: a potential co-targeted therapeutic approach in triple-negative breast cancer

Triple-negative breast cancer lacks an expression of ER, PR, and Her-2, has a poor prognosis, and there are no target therapies available. Therapeutic options to treat TNBC are limited and urgently needed. Strong evidence indicates that molecular signaling pathways have a significant function to regulate biological mechanisms and their abnormal expression endows with the development of cancer. PIM kinase is overexpressed in various human cancers including TNBC which is regulated by various signaling pathways that are crucial for cancer cell proliferation and survival and also make PIM kinase as an attractive drug target. One of the targets of the STAT3 signaling pathway is PIM1 that plays a key role in tumor progression and transformation. In this review, we accumulate the current scenario of the PIM-STAT3 axis that provides insights into the PIM1 and STAT3 inhibitors which can be developed as potential co-inhibitors as prospective anticancer agents.

Blueberry Juice Attenuates Pulmonary Fibrosis via Blocking the TGF-β1/Smad Signaling Pathway

Idiopathic pulmonary fibrosis (IPF) is a progressive, fatal, and chronic lung disease, lacking a validated and effective therapy. Blueberry has demonstrated multiple pharmacological activities including anti-inflammatory, antioxidant, and anticancer. Therefore, the objective of this study was to investigate whether blueberry juice (BBJ) could ameliorate IPF. Experiments in vitro revealed that BBJ could significantly reduce the expressions of TGF-β1 modulated fibrotic protein, which were involved in the cascade of fibrosis in NIH/3T3 cells and human pulmonary fibroblasts. In addition, for rat primary lung fibroblasts (RPLFs), BBJ promoted the cell apoptosis along with reducing the expressions of α-SMA, vimentin, and collagen I, while increasing the E-cadherin level. Furthermore, BBJ could reverse epithelial–mesenchymal transition (EMT) phenotypic changes and inhibit cell migration, along with inducing the upregulation of E-cadherin in A549 cells. Compared with the vehicle group, BBJ treatment alleviated fibrotic pathological changes and collagen deposition in both bleomycin-induced prevention and treatment pulmonary fibrosis models. In fibrotic lung tissues, BBJ remarkably suppressed the expressions of collagen I, α-SMA, and vimentin and improved E-cadherin, which may be related to its inhibition of the TGF-β1/Smad pathway and anti-inflammation efficacy. Taken together, these findings comprehensively proved that BBJ could effectively prevent and attenuate idiopathic pulmonary fibrosis via suppressing EMT and the TGF-β1/Smad signaling pathway.

IL-6/JAK/STAT3 Signaling in Breast Cancer Metastasis: Biology and Treatment

Breast cancer is the most commonly diagnosed cancer in women. Metastasis is the primary cause of mortality for breast cancer patients. Multiple mechanisms underlie breast cancer metastatic dissemination, including the interleukin-6 (IL-6)-mediated signaling pathway. IL-6 is a pleiotropic cytokine that plays an important role in multiple physiological processes including cell proliferation, immune surveillance, acute inflammation, metabolism, and bone remodeling. IL-6 binds to the IL-6 receptor (IL-6Rα) which subsequently binds to the glycoprotein 130 (gp130) receptor creating a signal transducing hexameric receptor complex. Janus kinases (JAKs) are recruited and activated; activated JAKs, in turn, phosphorylate signal transducer and activator of transcription 3 (STAT3) for activation, leading to gene regulation. Constitutively active IL-6/JAK/STAT3 signaling drives cancer cell proliferation and invasiveness while suppressing apoptosis, and STAT3 enhances IL-6 signaling to promote a vicious inflammatory loop. Aberrant expression of IL-6 occurs in multiple cancer types and is associated with poor clinical prognosis and metastasis. In breast cancer, the IL-6 pathway is frequently activated, which can promote breast cancer metastasis while simultaneously suppressing the anti-tumor immune response. Given these important roles in human cancers, multiple components of the IL-6 pathway are promising targets for cancer therapeutics and are currently being evaluated preclinically and clinically for breast cancer. This review covers the current biological understanding of the IL-6 signaling pathway and its impact on breast cancer metastasis, as well as, therapeutic interventions that target components of the IL-6 pathway including: IL-6, IL-6Rα, gp130 receptor, JAKs, and STAT3.

Ginsenoside Rh1 inhibits tumor growth in MDA-MB-231 breast cancer cells via mitochondrial ROS and ER stress-mediated signaling pathway

Ginsenoside-Rh1 (Rh1) is a ginseng-derived compound that has been reported to exert anticancer effects by regulating cell cycle arrest and apoptosis according to reactive oxygen species (ROS) production. However, the effects of Rh1 on mitochondrial dysfunction are involved in triple negative breast cancer (TNBC) cell apoptosis, and the related molecular mechanisms remain unknown. Rh1 treatment induced cell toxicity less than 50% at 50 μM. In addition, Rh1 induced apoptosis in TNBC cells through cleaved caspase-3 activation and G1/S arrest. The Rh1-treated TNBC cells showed a significant increase in mitochondrial ROS (mtROS), which in turn increased protein expression of mitochondrial molecules, such as Bak and cytochrome C, and caused the loss of mitochondrial membrane potential. Pretreatment with mitochondria-targeted antioxidant Mito-TEMPO alters the Rh1-reduced rate of mito- and glycol-ATP. Furthermore, Rh1 induces ER stress-mediated calcium accumulation via PERK/eIF2α/ATF4/CHOP pathway. Inhibition of ATF4 by siRNA transfection significantly inhibited Rh1-mediated apoptosis and calcium production. Interestingly, Mito-TEMPO treatment significantly reduced apoptosis and ER stress induced by Rh1. Finally, Rh1 at 5 mg/kg suppressed tumor growth through increased levels of ROS production, cleaved caspase-3, and ATF4 more than 5-fluorouracil treated group. Overall, our results suggest that Rh1 has potential for use in TNBC treatment.

Modulatory Effects of Biosynthesized Gold Nanoparticles Conjugated with Curcumin and Paclitaxel on Tumorigenesis and Metastatic Pathways-In Vitro and In Vivo Studies

Background: Breast cancer is the most common cancer in women globally, and diagnosing it early and finding potential drug candidates against multi-drug resistant metastatic breast cancers provide the possibilities of better treatment and extending life. Methods: The current study aimed to evaluate the synergistic anti-metastatic activity of Curcumin (Cur) and Paclitaxel (Pacli) individually, the combination of Curcumin–Paclitaxel (CP), and also in conjugation with gold nanoparticles (AuNP–Curcumin (Au-C), AuNP–Paclitaxel (Au-P), and AuNP–Curcumin–Paclitaxel (Au-CP)) in various in vitro and in vivo models. Results: The results from combination treatments of CP and Au-CP demonstrated excellent synergistic cytotoxic effects in triple-negative breast cancer cell lines (MDA MB 231 and 4T1) in in vitro and in vivo mouse models. Detailed mechanistic studies were performed that reveal that the anti-cancer effects were associated with the downregulation of the expression of VEGF, CYCLIN-D1, and STAT-3 genes and upregulation of the apoptotic Caspase-9 gene. The group of mice that received CP combination therapy (with and without gold nanoparticles) showed a significant reduction in the size of tumor when compared to the Pacli alone treatment and control groups. Conclusions: Together, the results suggest that the delivery of gold conjugated Au-CP formulations may help in modulating the outcomes of chemotherapy. The present study is well supported with observations from cell-based assays, molecular and histopathological analyses.

Natural Flavonoid Pectolinarigenin Alleviated Hyperuricemic Nephropathy via Suppressing TGFβ/SMAD3 and JAK2/STAT3 Signaling Pathways

Natural flavonoid pectolinarigenin (PEC) was reported to alleviate tubulointerstitial fibrosis of unilateral ureteral obstruction (UUO) mice in our previous study. To further investigate nephroprotective effects of PEC in hyperuricemic nephropathy (HN), adenine and potassium oxonate induced HN mice and uric acid-treated mouse kidney epithelial (TCMK-1) cells were employed in the study. As a result, PEC significantly lowered serum uric acid level and restored hyperuricemia-related kidney injury in HN mice. Meanwhile, PEC alleviated inflammation, fibrosis, and reduced adipokine FABP4 content in the kidneys of HN mice and uric acid-treated TCMK-1 cells. Mechanistically, PEC inhibited the TGF-β1 expression as well as the phosphorylation of transcription factor SMAD3 and STAT3 to regulate the corresponding inflammatory and fibrotic gene expression in kidney tissues. In conclusion, our results suggested that PEC could inhibit the activation of SMAD3 and STAT3 signaling to suppress inflammation and fibrosis, and thereby alleviate HN in mice.

A novel aryl-guanidinium derivative, VP79s, targets the signal transducer and activator of transcription 3 signaling pathway, downregulates myeloid cell leukaemia-1 and exhibits preclinical activity against multiple myeloma

AIMS

We have recently described a novel guanidinium-based compound, VP79s, which induces cytotoxicity in various cancer cell lines. Here, we aim to investigate the activity of VP79s and associated mechanisms of action in multiple myeloma (MM) cells in vitro and ex vivo.

MAIN METHODS

The effects of VP79s on cell viability and induction of apoptosis was examined in a panel of drug-sensitive and drug-resistant MM cell lines, as well as ex vivo patient samples and normal donor lymphocytes and platelets. Cell signaling pathways associated with the biological effects of VP79s were analysed by immunoblotting and flow cytometry. Gene expression changes were assessed by quantitative real-time PCR analysis.

KEY FINDINGS

VP79s was found to rapidly inhibit both constitutively active and IL-6-induced STAT3 signaling with concurrent downregulation of the IL-6 receptors, CD130 and CD126. VP79s induced a rapid and dose-dependent downregulation of anti-apoptotic Bcl-2 family member, myeloid cell leukaemia-1 (MCL-1). VP79s enhanced bortezomib induced cell death and was also found to overcome bone marrow stromal cell induced drug resistance. VP79s exhibited activity in ex vivo patient samples at concentrations which had no effect on peripheral blood mononuclear cells, lymphocytes and platelets isolated from healthy donors.

SIGNIFICANCE

As VP79s resulted in rapid inhibition of the key IL-6/STAT3 signaling pathway and downregulation of MCL-1 expression with subsequent selective anti-myeloma activity, VP79s may be a potential therapeutic agent with a novel mechanism of action in MM cells.

Unravelling the Anticancer Mechanisms of Traditional Herbal Medicines with Metabolomics

Metabolite profiling of cancer cells presents many opportunities for anticancer drug discovery. The Chinese, Indian, and African flora, in particular, offers a diverse source of anticancer therapeutics as documented in traditional folklores. In-depth scientific information relating to mechanisms of action, quality control, and safety profile will promote their extensive usage in cancer therapy. Metabolomics may be a more holistic strategy to gain valuable insights into the anticancer mechanisms of action of plants but this has remained largely unexplored. This review, therefore, presents the available metabolomics studies on the anticancer effects of herbal medicines commonly used in Africa and Asia. In addition, we present some scientifically understudied ‘candidate plants’ for cancer metabolomics studies and highlight the relevance of metabolomics in addressing other challenges facing the drug development of anticancer herbs. Finally, we discussed the challenges of using metabolomics to uncover the underlying mechanisms of potential anticancer herbs and the progress made in this regard.

Repurposing drugs as novel triple negative breast cancer therapeutics

BACKGROUND

Among all the types of breast cancer (BC), triple negative breast cancer (TNBC) is the most aggressive form having high metastasis and recurrence rate with limited treatment options. Conventional treatments such as chemotherapy and radiotherapy have lots of toxic side effects and also no FDA approved therapies are available till now. Repurposing of old clinically approved drugs towards various targets of TNBC is the new approach with lesser side effects and also leads to successful inexpensive drug development with less time consuming. Medicinal plants containg various phytoconstituents (flavonoids, alkaloids, phenols, essential oils, tanins, glycosides, lactones) plays very crucial role in combating various types of diseases and used in drug development process because of having lesser side effects.

OBJECTIVE

The present review focuses in summarization of various categories of repurposed drugs against multitarget of TNBC and also summarizes the phytochemical categories that targets TNBC singly or in combination with synthetic old drugs.

METHODS

Literature information was collected from various databases such as Pubmed, Web of Science, Scopus and Medline to understand and clarify the role and mechanism of repurposed synthetic drugs and phytoconstituents aginst TNBC by using keywords like "breast cancer", "repurposed drugs", "TNBC" and "phytoconstituents".

RESULTS

Various repurposed drugs and phytochemicals targeting different signaling pathways that exerts their cytotoxic activities on TNBC cells ultimately leads to apoptosis of cells and also lowers the recurrence rate and stops the metastasis process.

CONCLUSION

Inhibitory effects seen in different levels, which provides information and evidences to researchers towards drug developments process and thus further more investigations and researches need to be taken to get the better therapeutic treatment options against TNBC.

Ginsenoside Rh1 Prevents Migration and Invasion through Mitochondrial ROS-Mediated Inhibition of STAT3/NF-κB Signaling in MDA-MB-231 Cells

Breast cancer (BC) a very common cancer in women worldwide. Triple negative breast cancer (TNBC) has been shown to have a poor prognosis with a high level of tumor metastatic spread. Here, the inhibitory effects of ginsenoside-Rh1 (Rh1) on BC metastasis, and its underlying signaling pathway in TNBC were investigated. Rh1-treated MDA-MB-231 cells were analyzed for metastasis using a wound healing assay, transwell migration and invasion assay, western blotting, and qRT-PCR. Rh1 treatment significantly inhibited BC metastasis by inhibiting the both protein and mRNA levels of MMP2, MMP9, and VEGF-A. Further, Rh1-mediated inhibitory effect on BC migration was associated with mitochondrial ROS generation. Rh1 treatment significantly eliminated STAT3 phosphorylation and NF-κB transactivation to downregulate metastatic factors, such as MMP2, MMP9, and VEGF-A. In addition, Mito-TEMPO treatment reversed Rh1 effects on the activation of STAT3, NF-κB, and their transcriptional targets. Rh1 further enhanced the inhibitory effects of STAT3 or NF-κB specific inhibitor, stattic or BAY 11-7082 on MMP2, MMP9, and VEGF-A expression, respectively. In summary, our results revealed the potent anticancer effect of Rh1 on TNBC migration and invasion through mtROS-mediated inhibition of STAT3 and NF-κB signaling.

Design, synthesis and biological evaluation of 1H-pyrrolo[2,3-b]pyridine derivatives as potent fibroblast growth factor receptor inhibitors

Abnormal activation of FGFR signaling pathway plays an essential role in various types of tumors. Therefore, targeting FGFRs represents an attractive strategy for cancer therapy. Herein, we report a series of 1H-pyrrolo[2,3-b]pyridine derivatives with potent activities against FGFR1, 2, and 3. Among them, compound 4h exhibited potent FGFR inhibitory activity (FGFR1–4 IC₅₀ values of 7, 9, 25 and 712 nM, respectively). In vitro, 4h inhibited breast cancer 4T1 cell proliferation and induced its apoptosis. In addition, 4h also significantly inhibited the migration and invasion of 4T1 cells. Furthermore, 4h with low molecular weight would be an appealing lead compound which was beneficial to the subsequent optimization. In general, this research has been developing a class of 1H-pyrrolo[2,3-b]pyridine derivatives targeting FGFR with development prospects.

Discovery of a new class of 1H- pyrrorole [2,3-b]pyridine FGFR inhibitors with high ligand efficiency.

Coordinated regulation of immune contexture: crosstalk between STAT3 and immune cells during breast cancer progression

Recent insights into the molecular and cellular mechanisms underlying cancer development have revealed the tumor microenvironment (TME) immune cells to functionally affect the development and progression of breast cancer. However, insufficient evidence of TME immune modulators limit the clinical application of immunotherapy for advanced and metastatic breast cancers. Intercellular STAT3 activation of immune cells plays a central role in breast cancer TME immunosuppression and distant metastasis. Accumulating evidence suggests that targeting STAT3 and/or in combination with radiotherapy may enhance anti-cancer immune responses and rescue the systemic immunologic microenvironment in breast cancer. Indeed, apart from its oncogenic role in tumor cells, the functions of STAT3 in TME of breast cancer involve multiple types of immunosuppression and is associated with tumor cell metastasis. In this review, we summarize the available information on the functions of STAT3-related immune cells in TME of breast cancer, as well as the specific upstream and downstream targets. Additionally, we provide insights about the potential immunosuppression mechanisms of each type of evaluated immune cells. Video abstract.

Application of digital holographic tomography in antitumor effect of cantharides complex on 4T1 breast cancer cells

The study focuses on a methodology providing noninvasive monitoring and evaluation of the antitumor effect of traditional Chinese medicine, cantharides complex (canth), on 4T1 breast tumor cells. Digital holographic tomography (DHT) and developed data post-processing algorithms were used for quantitative estimation of changes in optical and morphological parameters of cells. We calculated and compared data on the refractive index, thickness, and projected area of 4T1 breast tumor cells in control untreated specimens and those treated with doxorubicin hydrochloride (DOX), canth, and their combinations. Post-treatment changes in cellular morphology recorded by DHT demonstrated that the two drugs led to noticeably different morphological changes in cells that can be presumably associated with different pathways of their death, apoptosis, or necrosis. The effect of combined treatment with these two drugs strongly depended on their relative concentrations and could lead to changes characteristic either for DOX or for canth; however, being more profound than those obtained when using each drug solely. The results obtained by DHT are in a good correspondence with commonly used cell viability analysis and immunofluorescent analysis of changes in cellular cytoskeleton.

The Tetramethylpyrazine Derivative Statmp-151: A Novel Small Molecule Stat3 Inhibitor With Promising Activity Against Breast Cancer

Breast cancer is the most common malignancy in women and is a molecularly heterogeneous disease. Signal transducer and activator of transcription 3 (Stat3) is overexpressed and hyperactivated in a variety of human tumours, including breast cancer, thus representing a promising target for breast cancer treatment. In the present study, we evaluated the activities of a novel Stat3 inhibitor named Statmp-151 in the human breast cancer cell lines MCF-7 and MDA-MB-231 and the murine mammary carcinoma cell line 4T1. The in vitro results showed that Statmp-151 inhibited the proliferation of breast cancer cell lines in a dose- and time-dependent manner and suppressed the phosphorylation of Stat3 in a dose-dependent manner. Flow cytometry (FCM) assays revealed that Statmp-151 affected mitochondrial membrane potential and reactive oxygen species (ROS) production. Furthermore, Statmp-151 inhibited cell migration, as shown by analysis of the matrix metalloproteinases MMP2 and MMP9. Finally, in a 4T1 tumour-bearing mouse model, intraperitoneal injection of 30 mg/kg/day Statmp-151 significantly suppressed the growth of tumours without obvious toxicity. These results indicated that Statmp-151 might be a potential candidate for the treatment of breast cancer.

The expression and clinical significance of signal transducer and activator of transcription 3, tumor necrosis factor α induced protein 8-like 2, and runt-related transcription factor 1 in breast cancer patients

BACKGROUND

This study explored the expression and clinical significance of signal transducer and activator of transcription 3 (STAT3), tumor necrosis factor α induced protein 8-like 2 (TIPE2), and runt-related transcription factor 1 (RUNX1) in breast cancer tissue.

METHODS

From October 2014 to October 2017, 68 breast cancer patients (68 breast cancer tissue specimens) who underwent a radical mastectomy in our hospital were set as the observation group and the corresponding normal tissue 3 cm away from the cancer tissue was selected as the control group. The expression levels of STAT3, TIPE2, and RUNX1 in the two groups were compared via immunohistochemical staining. Multiple logistic regression was then used to analyze the related risk factors affecting the 2-year prognosis of breast cancer patients. The receiver operating characteristic (ROC) curve was then plotted and the area under the ROC curve was calculated. The predictive values of STAT3, TIPE2, and RUNX1, and the predictive value of the three transcription factors combined on the 2-year prognostic survival of breast cancer patients were determined.

RESULTS

(I) In the observation group, the positive expression of STAT3 and the negative expression of TIPE2 and RUNX1 were significantly higher than those in the control group (P<0.05). (II) Of the 68 patients, 51 survived within 2 years and 17 patients died. Positive STAT3 expression, negative TIPE2 expression, negative RUNX1 expression, poor histological differentiation, TNM stage III-IV, and distant metastasis were all identified as factors that can affect the 2-year prognosis of breast cancer patients (P<0.05). (III) The ROC curve analysis examining the 2-year prognostic survival of breast cancer patients showed that the area under the curve achieved the largest value when the predictive values of STAT3, TIPE2, RUNX1 were combined.

CONCLUSIONS

The levels of STAT3, TIPE2, and RUNX1 expression in breast cancer tissues were significantly different from that in adjacent normal tissues. This suggested that the combined detection of STAT3, TIPE2, and RUNX1 may improve the rate of early breast cancer diagnosis. Furthermore, STAT3, TIPE2, and RUNX1 may be useful in evaluating the prognosis of the patients with breast cancer.

The signaling pathways and targets of traditional Chinese medicine and natural medicine in triple-negative breast cancer

ETHNOPHARMACOLOGICAL RELEVANCE

Triple-negative breast cancer (TNBC) has a poorer prognosis than other subtypes due to its strong invasion and higher risk of distant metastasis. Traditional Chinese medicine (TCM) and natural medicine have the unique advantages of multitargets and small side-effects and may be used as long-term complementary and alternative therapies.

AIM OF THE REVIEW

The present article summarizes the classical signaling pathways and potential targets by the action of TCM and natural medicine (including extracts, active constituents and formulas) on TNBC and provides evidence for its clinical efficacy.

METHODS

The literature information was acquired from the scientific databases PubMed, Web of Science and CNKI from January 2010 to June 2020, and it was designed to elucidate the internal mechanism and role of TCM and natural medicine in the treatment of TNBC. The search key words included "Triple negative breast cancer" or "triple negative breast carcinoma", "TNBC" and "traditional Chinese medicine" or "Chinese herbal medicine", "medicinal plant", "natural plant", and "herb".

RESULTS

We described the antitumor activity of TCM and natural medicine in TNBC based on different signaling pathways. Plant medicine and herbal formulas regulated the related gene and protein expression via pathways such as PI3K/AKT/mTOR, MAPK and Wnt/β-catenin, which inhibit the growth, proliferation, migration, invasion and metastasis of TNBC cells.

CONCLUSION

The inhibitory effect of TCM and natural medicine on tumors was reflected in multiple levels and multiple pathways, providing reasonable evidence for new drug development. To make TCM and natural medicine widely and flexibly used in clinical practice, the efficacy, safety and mechanism of action need more in-depth experimental research.

Pectolinarigenin inhibits cell viability, migration and invasion and induces apoptosis via a ROS-mitochondrial apoptotic pathway in melanoma cells

Pectolinarigenin a plant secondary metabolite that has various biological effects, including the inhibition of melanogenesis and tumor growth. Melanoma has a high degree of malignancy, with rapid metastasis and severe drug resistance, explaining the need for new candidate drugs that inhibit tumor growth and metastasis. However, the pharmacological action and mechanism of pectolinarigenin on the growth and metastasis of melanoma remain elusive. Thus, the present study aimed to investigate the role of pectolinarigenin in melanoma cell proliferation, apoptosis, migration and invasion. Apoptotic and metastasis-associated proteins were analyzed using western blotting. The results demonstrated that pectolinarigenin treatment resulted in growth inhibition and apoptosis induction in melanoma cells, arising from the loss of mitochondrial transmembrane potential, reactive oxygen species and the altered expression of apoptosis-associated proteins. In addition, wound-healing and Transwell assays demonstrated the potential of pectolinarigenin to impair the migration and invasion of melanoma cells in accordance with the changes in the expression of the associated proteins. Therefore, the results of the present study suggested that pectolinarigenin may serve a pivotal role in promoting melanoma cell apoptosis and reducing metastasis, and may thus be a promising potential candidate for an anti-melanoma treatment strategy.

Flavonoids in Cancer Metastasis

Metastasis represents a serious complication in the treatment of cancer. Flavonoids are plant secondary metabolites exerting various health beneficiary effects. The effects of flavonoids against cancer are associated not only with early stages of the cancer process, but also with cancer progression and spread into distant sites. Flavonoids showed potent anti-cancer effects against various cancer models in vitro and in vivo, mediated via regulation of key signaling pathways involved in the migration and invasion of cancer cells and metastatic progression, including key regulators of epithelial-mesenchymal transition or regulatory molecules such as MMPs, uPA/uPAR, TGF-β and other contributors of the complex process of metastatic spread. Moreover, flavonoids modulated also the expression of genes associated with the progression of cancer and improved inflammatory status, a part of the complex process involved in the development of metastasis. Flavonoids also documented clear potential to improve the anti-cancer effectiveness of conventional chemotherapeutic agents. Most importantly, flavonoids represent environmentally-friendly and cost-effective substances; moreover, a wide spectrum of different flavonoids demonstrated safety and minimal side effects during long-termed administration. In addition, the bioavailability of flavonoids can be improved by their conjugation with metal ions or structural modifications by radiation. In conclusion, anti-cancer effects of flavonoids, targeting all phases of carcinogenesis including metastatic progression, should be implemented into clinical cancer research in order to strengthen their potential use in the future targeted prevention and therapy of cancer in high-risk individuals or patients with aggressive cancer disease with metastatic potential.