Current Advancements of Plant-Derived Agents for Triple-Negative Breast Cancer Therapy through Deregulating Cancer Cell Functions and Reprogramming Tumor Microenvironment

Crocin inhibit the metastasis of MDA-MB-231 cell line by suppressing epithelial to mesenchymal transition through WNT/β-catenin signalling pathway

Background

Triple-negative breast cancer has the poorest prognosis and survival rates compared to other breast cancer subtypes due to its invasive behaviours. This type of cancer does not respond to biological therapies and exhibits resistance to available treatment options. Therefore, it is imperative to discover new therapeutics to address this challenge.

Methods

In this study, a TNBC cell line was utilized to investigate the anti-metastatic effect of crocin on the Wnt/β-catenin pathway. Cell proliferation was assessed using the MTT assay, and the effects of crocin on migration were monitored through transwell and wound healing experiments. The expression of specific epithelial-mesenchymal transition marker genes was evaluated using real-time polymerase chain reaction, and β-catenin expression was also examined through real-time polymerase chain reaction.

Results

The findings revealed that crocin significantly inhibits cell proliferation and migration of tumour cells in a dose-dependent manner. Moreover, crocin decreased the expression of Vimentin, Snail, Zeb-1, and β-catenin. Additionally, crocin increased the expression of E-cadherin in the MDA-MB-231 cell line.

Conclusions

The results demonstrated an association between crocin and the Wnt/β-catenin signalling pathway. In conclusion, this study establishes that crocin holds promise as a potential therapeutic option for triple-negative breast cancer.

Nanoparticle drug delivery systems responsive to tumor microenvironment: Promising alternatives in the treatment of triple-negative breast cancer

The conventional therapeutic treatment of triple-negative breast cancer (TNBC) is negatively influenced by the development of tumor cell drug resistant, and systemic toxicity of therapeutic agents due to off-target activity. In accordance with research findings, nanoparticles (NPs) responsive to the tumor microenvironment (TME) have been discovered for providing opportunities to selectively target tumor cells via active targeting or Enhanced Permeability and Retention (EPR) effect. The combination of the TME control and therapeutic NPs offers promising solutions for improving the prognosis of the TNBC because the TME actively participates in tumor growth, metastasis, and drug resistance. The NP-based systems leverage stimulus-responsive mechanisms, such as low pH value, hypoxic, excessive secretion enzyme, concentration of glutathione (GSH)/reactive oxygen species (ROS), and high concentration of Adenosine triphosphate (ATP) to combat TNBC progression. Concurrently, NP-based stimulus-responsive introduces a novel approach for drug dosage design, administration, and modification of the pharmacokinetics of conventional chemotherapy and immunotherapy drugs. This review provides a comprehensive examination of the strengths, limitations, applications, perspectives, and future expectations of both novel and traditional stimulus-responsive NP-based drug delivery systems for improving outcomes in the medical practice of TNBC. This article is categorized under: Therapeutic Approaches and Drug Discovery > Emerging Technologies Nanotechnology Approaches to Biology > Nanoscale Systems in Biology Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease.

Glabridin plays dual action to intensify anti-metastatic potential of paclitaxel via impeding CYP2C8 in liver and CYP2J2/EETs in tumor of an orthotopic mouse model of breast cancer

In spite of unprecedented advances in modern cancer therapy, there is still a dearth of targeted therapy to circumvent triple-negative breast cancer (TNBC). Paclitaxel is the front-line therapy against TNBC, but the main constraints of its treatment are dose-related adverse effects and emerging chemoresistance. In this context, glabridin (phytoconstituent from Glycyrrhiza glabra) is reported to hit multiple signalling pathways at the in-vitro level, but hardly any information is known at the in-vivo level. We aimed here to elucidate glabridin potential with an underlying mechanism in combination with a low dose of paclitaxel using a highly aggressive mouse mammary carcinoma model. Glabridin potentiated the anti-metastatic efficacy of paclitaxel by substantially curtailing tumor burden and diminishing lung nodule formation. Moreover, glabridin remarkably attenuated epithelial-mesenchymal transition (EMT) traits of hostile cancer cells via up-regulating (E-cadherin & occludin) and down-regulating (Vimentin & Zeb1) vital EMT markers. Besides, glabridin amplified apoptotic induction effect of paclitaxel in tumor tissue by declining or elevating pro-apoptotic (Procaspase-9 or Cleaved Caspase-9 & Bax) and reducing anti-apoptotic (Bcl-2) markers. Additionally, concomitant treatment of glabridin and paclitaxel predominantly lessened CYP2J2 expression with marked lowering of epoxyeicosatrienoic acid (EET)'s levels in tumor tissue to reinforce the anti-tumor impact. Simultaneous administration of glabridin with paclitaxel notably enhanced plasma exposure and delayed clearance of paclitaxel, which was mainly arbitrated by CYP2C8-mediated slowdown of paclitaxel metabolism in the liver. The fact of intense CYP2C8 inhibitory action of glabridin was also ascertained using human liver microsomes. Concisely, glabridin plays a dual role in boosting anti-metastatic activity by augmenting paclitaxel exposure via CYP2C8 inhibition-mediated delaying paclitaxel metabolism and limiting tumorigenesis via CYP2J2 inhibition-mediated restricting EETs level. Considering the safety, reported protective efficacy, and the current study results of boosted anti-metastatic effects, further investigations are warranted as a promising neoadjuvant therapy for crux paclitaxel chemoresistance and cancer recurrence.

OTUD1 chemosensitizes triple-negative breast cancer to doxorubicin by modulating P16 expression

Chemotherapy remains a critical component of triple-negative breast cancer (TNBC) treatment; however, patients often develop resistance to chemotherapeutic agents. Accumulating evidence indicates that deubiquitylases (DUBs) play pivotal roles in regulating cell proliferation, differentiation, apoptosis, and tumorigenesis. Deubiquitylase OTUD1 is considered a tumor suppressor in various cancers, yet its role in doxorubicin sensitivity in breast cancer patients remains inadequately understood. In this study, we investigated the expression levels and prognostic role of OTUD1 in breast cancer. Our findings demonstrated that OTUD1 was downregulated in TNBC, and lower OTUD1 expression levels were correlated with poor prognosis. We utilized the CCK-8 cell viability assay, flow cytometric analysis, and a TNBC mouse xenograft model to examine the influence of OTUD1 on doxorubicin (DOX) chemotherapy sensitivity in vitro and in vivo. Western blot and immunohistochemistry were employed to explore the correlation between OTUD1 and P16. Our results indicated that upregulation of OTUD1 expression inhibits TNBC cell proliferation and enhances its sensitivity to doxorubicin. Additionally, rescue experiments confirmed that the chemosensitizing effect of OTUD1 overexpression could be reversed by the inhibition of P16. Therefore, our findings reveal that OTUD1 sensitizes TNBC cells to DOX by upregulating P16 expression, suggesting a potential new diagnostic biomarker and therapeutic target for the future treatment of TNBC.

Scutebarbatine A induces ROS-mediated DNA damage and apoptosis in breast cancer cells by modulating MAPK and EGFR/Akt signaling pathway

Scutebarbatine A (SBT-A), a diterpenoid alkaloid, has exerted cytotoxicity on hepatocellular carcinoma cells in our previous works. Here, the antitumor activity of SBT-A in breast cancer cells and the underlying mechanism were explored. The anti-proliferative effect of SBT-A was measured by trypan blue staining, 5-ethynyl-2'-deoxyuridine (EdU) incorporation and colony formation assay. DNA double-strand breaks (DSBs) were evaluated by observing the nuclear focus formation of γ-H2AX. Cell cycle distribution was assessed by flow cytometry. Apoptosis was determined by a TUNEL assay. Intracellular reactive oxygen species (ROS) generation and superoxide production were measured with 2', 7'-dichlorofluorescein diacetate (DCFH-DA) and dihydroethidium (DHE) staining, respectively. The results indicated that SBT-A showed a dose-dependent cytotoxic effect against breast cancer cells while revealing less toxicity toward MCF-10A breast epithelial cells. Moreover, SBT-A remarkably induced DNA damage, cell cycle arrest and apoptosis in both MDA-MB-231 and MCF-7 cells. SBT-A treatment increased the levels of ROS and cytosolic superoxide production. Pretreatment with N-acetyl cysteine (NAC), a ROS scavenger, was sufficient to block viability reduction, DNA damage, apoptosis and endoplasmic reticulum (ER) stress caused by SBT-A. By exposure to SBT-A, the phosphorylation of c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase (p38MAPK) was upregulated, while the phosphorylation of extracellular signal-regulated kinase (ERK) was downregulated. In addition, SBT-A inhibited the EGFR signaling pathway by decreasing EGFR expression and phosphorylation of Akt and p70S6K. As mentioned above, SBT-A has a potent inhibitory effect on breast cancer cells through induction of DNA damage, apoptosis and ER stress via ROS generation and modulation of MAPK and EGFR/Akt signaling pathway.

An in vitro investigation of the apoptosis-inducing activity of corosolic acid in breast cancer cells

Objectives

Breast cancer is the most prevalent cancer among females with different molecular subtypes. Corosolic acid is a pentacyclic triterpenoid with anti-cancer properties.

Materials and Methods

The MTT assay was used to assess the cytotoxic activity of corosolic acid on MDA-MB-231 and MCF7 cell lines. To determine the apoptotic cells, the flow cytometry technique was utilized. The expression levels of apoptosis-related genes and proteins were quantified using quantitative real time-PCR (qRT-PCR) and Western blotting methods. The activity of caspase enzymes was measured by spectrophotometry.

Results

Corosolic acid significantly inhibited the proliferation of both cell lines compared with controls. This agent markedly induced apoptosis in MDA-MB-231 cells but did not affect MCF7 cells compared with controls. Treating the MADA-MB-231 and MCF7 cell lines with corosolic acid showed an inducing effect on apoptosis-associated caspases, including Caspase-8, 9, and -3, in MADA-MB-231 cells with no effect on apoptotic markers in MCF7 cells. Further experiments uncovered corosolic acid-induced apoptosis in MADA-MB-231 cells by decreasing the expression of the phosphorylated form of JAK2 and STAT3 proteins.

Conclusion

The present data suggested that corosolic acid is an apoptosis-inducing phytochemical in triple-negative breast cancer MADA-MB-231 cells. Also, corosolic acid triggered apoptosis in these cells by stimulating both pathways of apoptosis and inhibiting the JAK/STAT signaling. Furthermore, corosolic acid was found to inhibit MCF7 cell proliferation by a non-apoptotic mechanism.

Carrier-Free Nanoplatform via Evoking Pyroptosis and Immune Response against Breast Cancer

Pyroptosis, as a novel mode of cell death, has been proven to have impressive antitumor effects. Dying cells undergoing pyroptosis can elicit antitumor immunity by the release of tumor-associated antigens (TAAs) and damage-associated molecular patterns (DAMPs). Accordingly, developing an effective, stable, and controllable nanoplatform that can promote these two side effects is a promising option for cancer therapy. In this study, we designed a carrier-free chemo-photodynamic nanoplatform (A-C/NPs) using a co-assembly strategy with cytarabine (Ara-C) and chlorin e6 (Ce6) to induce pyroptosis and a subsequent immune response against breast cancer. Mechanistically, A-C/NPs can trigger GSDME-mediated pyroptosis in a controllable manner through reactive oxygen species (ROS) accumulation, causing immunogenic cell death (ICD), in which dying cells release high-mobility group box 1 (HMGB1), adenosine triphosphate (ATP), and calcitonin (CRT). Additionally, Ara-C can stimulate the maturation of cytotoxic T lymphocytes to act synergistically with Ce6-mediated immunogenic cell death (ICD), collectively augmenting the anticancer effect of A-C/NPs. The A-C/NPs showed excellent suppressive effects on the growth of orthotopic, abscopal, and recurrent tumors in a breast cancer mouse model. The chemo-photodynamic therapy (PDT) using the proposed nanomedicine strategy could be a novel strategy for triggering pyroptosis and improving the global anticancer immune response.

Resveratrol in breast cancer treatment: from cellular effects to molecular mechanisms of action

Breast cancer (BC) is one of the most common cancers in females and is responsible for the highest cancer-related deaths following lung cancer. The complex tumor microenvironment and the aggressive behavior, heterogenous nature, high proliferation rate, and ability to resist treatment are the most well-known features of BC. Accordingly, it is critical to find an effective therapeutic agent to overcome these deleterious features of BC. Resveratrol (RES) is a polyphenol and can be found in common foods, such as pistachios, peanuts, bilberries, blueberries, and grapes. It has been used as a therapeutic agent for various diseases, such as diabetes, cardiovascular diseases, inflammation, and cancer. The anticancer mechanisms of RES in regard to breast cancer include the inhibition of cell proliferation, and reduction of cell viability, invasion, and metastasis. In addition, the synergistic effects of RES in combination with other chemotherapeutic agents, such as docetaxel, paclitaxel, cisplatin, and/or doxorubicin may contribute to enhancing the anticancer properties of RES on BC cells. Although, it demonstrates promising therapeutic features, the low water solubility of RES limits its use, suggesting the use of delivery systems to improve its bioavailability. Several types of nano drug delivery systems have therefore been introduced as good candidates for RES delivery. Due to RES's promising potential as a chemopreventive and chemotherapeutic agent for BC, this review aims to explore the anticancer mechanisms of RES using the most up to date research and addresses the effects of using nanomaterials as delivery systems to improve the anticancer properties of RES.

Amaryllidaceae-Type Alkaloids from Pancratium maritimum: Apoptosis-Inducing Effect and Cell Cycle Arrest on Triple-Negative Breast Cancer Cells

Aiming to find Amaryllidaceae alkaloids against breast cancer, including the highly aggressive triple-negative breast cancer, the phytochemical study of Pancratium maritimum was carried out. Several Amaryllidaceae-type alkaloids, bearing scaffolds of the haemanthamine-, homolycorine-, lycorine-, galanthamine-, and tazettine-type were isolated (3–11), along with one alkamide (2) and a phenolic compound (1). The antiproliferative effect of compounds (1–11) was evaluated by the sulforhodamine B assay against triple-negative breast cancer cell lines MDA-MB-231 and MDA-MB-468, breast cancer cells MCF-7, and the non-malignant fibroblast (HFF-1) and breast (MCF12A) cell lines. The alkaloids 3, 5, 7, and 11 showed significant growth inhibitory effects against all breast cancer cell lines, with IC₅₀ (half-maximal inhibitory concentration) values ranging from 0.73 to 16.3 µM. The homolycorine-type alkaloid 7 was selected for further investigation in MDA-MB-231 cells. In the annexin-V assay, compound 7 increased cell death by apoptosis, which was substantiated, in western blot analyses, by the increased expression of the pro-apoptotic protein Bax, and the decreased expression of the anti-apoptotic protein Bcl-xL. Consistently, it further stimulated mitochondrial reactive oxygen species (ROS) generation. The antiproliferative effect of compound 7 was also associated with G2/M cell cycle arrest, which was supported by an increase in the p21 protein expression levels. In MDA-MB-231 cells, compound 7 also exhibited synergistic effects with conventional chemotherapeutic drugs such as etoposide.

Ameliorating Effect of Crassocephalum rabens (Asteraceae) Extract on Skin Aging: A Randomized, Parallel, Double-Blind, and Placebo-Controlled Study

Crassocephalum rabens (Asteraceae) is a common herb used in Taiwanese folk medicine to treat inflammation-related syndromes. Pharmacological studies have revealed that galactolipids exhibit anti-oxidative, anti-inflammatory, and anti-hyaluronidase activities and improve skin wrinkles, moisture, and elasticity in healthy subjects. However, the anti-aging effects of C. rabens and its primary active compound, 1,2-di-O-linolenoyl-3-O-β-galactopyranosyl-sn-glycerol (dLGG), remain elusive. Here, we investigated whether C. rabens can improve skin conditions in healthy individuals using a double-blind approach. Forty enrolled volunteers were randomly and equally assigned to the control or treatment group and were required to take either a placebo or a C. rabens extract capsule daily for one month. Skin parameters were measured before and after the study. The results showed significant differences in skin elasticity, wrinkles, collagen content, brightness, and hydration between the baseline and week 4 in the treatment group. Particularly, compared with those in the placebo group, skin wrinkles (p < 0.05), brightness (p < 0.001), collagen content (p < 0.01), and UV spots (p < 0.05) were notably improved after treatment with the C. rabens extract. Our study successfully demonstrated the application of C. rabens in preventing skin aging. Further investigations will be conducted to study the underlying anti-aging mechanism of dLGG.