Caspase-3 mediated switch therapy of self-triggered and long-acting prodrugs for metastatic TNBC

Specific signaling pathways mediated programmed cell death in tumor microenvironment and target therapies

Increasing evidence has shown that programmed cell death (PCD) plays a crucial role in tumorigenesis and cancer progression. The components of PCD are complex and include various mechanisms such as apoptosis, necroptosis, alkaliptosis, oxeiptosis, and anoikis, all of which are interrelated in their functions and regulatory pathways. Given the significance of these processes, it is essential to conduct a comprehensive study on PCD to elucidate its multifaceted nature. Key signaling pathways, particularly the caspase signaling pathway, the RIPK1/RIPK3/MLKL pathway, and the mTOR signaling pathway, are pivotal in regulating PCD and influencing tumor progression. In this review, we briefly describe the generation mechanisms of different PCD components and focus on the regulatory mechanisms of these three major signaling pathways within the context of global PCD. Furthermore, we discuss various tumor therapeutic compounds that target different signaling axes of these pathways, which may provide novel strategies for effective tumor therapy and help improve patient outcomes in cancer treatment.

Injectable polydopamine/curcumin dual-modified polylactic acid/polycaprolactone coaxial staple fibers for chronotropic treatment of oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) is one of the most prevalent malignant tumors in the oral and maxillofacial region. Traditional treatments for OSCC, including surgery, radiotherapy, and chemotherapy, often lead to severe adverse effects. Therefore, the development of safe and effective novel cancer therapies is crucial for achieving synergistic cancer treatment, significantly enhancing patient survival and quality of life. In this study, triaxial electrospinning combined with freeze-shortening technology was employed to prepare injectable short fibers that provided a sustained release of curcumin (CUR). Subsequently, polydopamine (PDA) was modified on the surface of the short fibers to create PDA@CUR@PCL/PLA. The developed injectable short fibers represented a significant advancement in reducing the risks associated with the surgical implantation of traditional two-dimensional fibrous membranes. These fibers were coated with dopamine, which imparted notable significant photothermal effects, facilitating the rapid destruction of cancer cells. Furthermore, the core-loaded CUR was released in a pH-responsive manner and demonstrated a sustained anti-tumor effect. Cellular and animal experiments indicated that these composite short fibers could effectively eliminate oral cancer cells through a synergistic combination of photothermal and drug therapies without apparent toxic side effects. The developed injectable coaxial PDA@CUR@PCL/PLA short fibers are expected to provide a novel treatment approach for OSCC.

PDCdb: the biological activity and pharmaceutical information of peptide-drug conjugate (PDC)

Peptide-drug conjugates (PDCs) have emerged as a promising class of targeted therapeutics with substantial pharmaceutical advantages and market potentials, which is a combination of a peptide (selective to the disease-relevant target), a linker (stable in circulation but cleavable at target site) and a cytotoxic/radioactive drug (efficacious/traceable for disease). Among existing PDCs, those based on radiopharmaceuticals (a.k.a. radioactive drugs) are valued due to their accurate imaging and targeted destruction of disease sites. It's demanded to accumulate the biological activity and pharmaceutical information of PDCs. Herein, a database PDCdb was thus constructed to systematically describe these valuable data. Particularly, biological activities for 2036 PDCs were retrieved from literatures, which resulted in 1684, 613 and 2753 activity data generated based on clinical trial, animal model and cell line, respectively. Furthermore, the pharmaceutical information for all 2036 PDCs was collected, which gave the diverse data of (a) ADME property, plasma half-life and administration approach of a PDC and (b) chemical modification, primary target, mode of action, conjugating feature of the constituent peptide/linker/drug. In sum, PDCdb systematically provided the biological activities and pharmaceutical information for the most comprehensive list of PDCs among the available databases, which was expected to attract broad interest from related communities and could be freely accessible at: https://idrblab.org/PDCdb/.

Stimuli-responsive prodrugs with self-immolative linker for improved cancer therapy

Self-immolative prodrugs have gained significant attention as an innovative approach for targeted cancer therapy. These prodrugs are engineered to release the active anticancer agents in response to specific triggers within the tumor microenvironment, thereby improving therapeutic precision while reducing systemic toxicity. This review focuses on the molecular architecture and design principles of self-immolative prodrugs, emphasizing the role of stimuli-responsive linkers and activation mechanisms that enable controlled drug release. Recent advancements in this field include the development of prodrugs that incorporate targeting moieties for enhanced site-specificity. Moreover, the review discusses the incorporation of targeting moieties to achieve site-specific drug delivery, thereby improving the selectivity of treatment. By summarizing key research from the past five years, this review highlights the potential of self-immolative prodrugs to revolutionize cancer treatment strategies and pave the way for their integration into clinical practice.

Repurposing of sericin combined with dactolisib or vitamin D to combat non-small lung cancer cells through computational and biological investigations

This study aims to repurpose sericin in combating non-small lung cancer cells (A549 and H460) by combining it with dactolisib or vitamin D to reduce the dose of dactolisib and boost the anticancer effectiveness of dactolisib and vitamin D. Therefore, the binding affinities of individual and combined drugs were examined using in silico and protein-protein interaction studies, targeting NF-κB, Cyclin D1, p-AKT, and VEGF1 proteins. The findings manifested remarkable affinities for combinatorial drugs compared to individual compounds. To substantiate these findings, the combined IC50 for each combination (sericin + dactolisib and sericin + vitamin D) were determined, reporting 31.9 and 41.8 µg/ml, respectively, against A549 cells and 47.9 and 55.3 µg/ml, respectively, against H460 cells. Furthermore, combination indices were assessed to lower the doses of each drug. Interestingly, in vitro results exhibited marked diminutions in NF-κB, Cyclin D1, p-AKT, and VEGF1 after treatment with sericin + dactolisib and sericin + vitamin D compared to control lung cancer cells and those treated with a single drug. Moreover, A549 and H460 cells treated with both combinations demonstrated augmented caspase-3 levels, implying substantial apoptotic activity. Altogether, these results accentuated the prospective implementation of sericin in combination with dactolisib and vitamin D at low doses to preclude lung cancer cell proliferation.

Synergistic anticancer immunity in metastatic triple-negative breast cancer through an in situ amplifying Peptide-Drug Conjugate

Despite significant progress in combining cancer immunotherapy with chemotherapy to treat triple negative breast cancer (TNBC), challenges persist due to target depletion and tumor heterogeneity, especially in metastasis. Chemotherapy lacks precise targeting abilities, and targeted therapy is inadequate in addressing the diverse heterogeneity of tumors. To address these challenges, we introduce RGDEVD-DOX as a tumor-specific immunogenic agent, namely TPD1, which targets integrin αvβ3 and gets continuously activated by apoptosis. TPD1 facilitates the caspase-3-mediated in situ amplification that results in tumor-specific accumulation of doxorubicin. This local concentration of doxorubicin induces immunogenic cell death and promotes the recruitment of immune cells to the tumor site. Notably, the tumor-targeting capabilities of TPD1 help bypass the systemic immunotoxicity of doxorubicin. Consequently, this alters the tumor microenvironment, converting it into a 'hot' tumor that is more susceptible to immune checkpoint inhibition. We demonstrated the anti-metastatic and anti-cancer efficacy of this treatment using various xenograft and metastatic models. This study underscores the high potential of caspase-3 cleavable peptide-drug conjugates to be used in conjunction with anti-cancer immunotherapies.

Advances in tumor stroma-based targeted delivery

The tumor stroma plays a crucial role in tumor progression, and the interactions between the extracellular matrix, tumor cells, and stromal cells collectively influence tumor progression and the efficacy of therapeutic agents. Currently, utilizing components of the tumor stroma for drug delivery is a noteworthy strategy. A number of targeted drug delivery systems designed based on tumor stromal components are entering clinical trials. Therefore, this paper provides a thorough examination of the function of tumor stroma in the advancement of targeted drug delivery systems. One approach is to use tumor stromal components for targeted drug delivery, which includes certain stromal components possessing inherent targeting capabilities like HA, laminin, along with targeting stromal cells homologously. Another method entails directly focusing on tumor stromal components to reshape the tumor stroma and facilitate drug delivery. These drug delivery systems exhibit great potential in more effective cancer therapy strategies, such as precise targeting, enhanced penetration, improved safety profile, and biocompatibility. Ultimately, the deployment of these drug delivery systems can deepen our comprehension of tumor stroma and the advanced development of corresponding drug delivery systems.

Unveiling the Mechanism of the ChaiShao Shugan Formula Against Triple-Negative Breast Cancer

Background

The ChaiShao Shugan Formula (CSSGF) is a traditional Chinese medicine formula with recently identified therapeutic value in triple-negative breast cancer (TNBC). This study aimed to elucidate the underlying mechanism of CSSGF in TNBC treatment.

Methods

TNBC targets were analyzed using R and data were from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. The major ingredients and related protein targets of CSSGF were explored via the Traditional Chinese Medicine Systems Pharmacology database, and an ingredient-target network was constructed via Cytoscape to identify hub genes. The STRING database was used to construct the PPI network. GO and KEGG enrichment analyses were performed via R to obtain the main targets. The online tool Kaplan‒Meier plotter was used to identify the prognostic genes. Molecular docking was applied to the core target genes and active ingredients. MDA-MB-231 and MCF-7 cell lines were used to verify the efficacy of the various drugs.

Results

A total of 4562 genes were screened as TNBC target genes. The PPI network consisted of 89 nodes and 845 edges. Our study indicated that quercetin, beta-sitosterol, luteolin and catechin might be the core ingredients of CSSGF, and EGFR and c-Myc might be the latent therapeutic targets of CSSGF in the treatment of TNBC. GO and KEGG analyses indicated that the anticancer effect of CSSGF on TNBC was mainly associated with DNA binding, transcription factor binding, and other biological processes. The related signaling pathways mainly involved the TNF-a, IL-17, and apoptosis pathways. The molecular docking data indicated that quercetin, beta-sitosterol, luteolin, and catechin had high affinity for EGFR, JUN, Caspase-3 and ESR1, respectively. In vitro, we found that CSSGF could suppress the expression of c-Myc or promote the expression of EGFR. In addition, we found that quercetin downregulates c-Myc expression in two BC cell lines.

Conclusion

This study revealed the effective ingredients and latent molecular mechanism of action of CSSGF against TNBC and confirmed that quercetin could target c-Myc to induce anti-BC effects.

CXCR4-Targeted Macrophage-Derived Biomimetic Hybrid Vesicle Nanoplatform for Enhanced Cancer Therapy through Codelivery of Manganese and Doxorubicin

Immune-cell-derived membranes have garnered significant attention as innovative delivery modalities in cancer immunotherapy for their intrinsic immune-modulating functionalities and superior biocompatibilities. Integrating additional parental cell membranes or synthetic lipid vesicles into cellular vesicles can further potentiate their capacities to perform combinatorial pharmacological activities in activating antitumor immunity, thus providing insights into the potential of hybrid cellular vesicles as versatile delivery vehicles for cancer immunotherapy. Here, we have developed a macrophage-membrane-derived hybrid vesicle that has the dual functions of transporting immunotherapeutic drugs and shaping the polarization of tumor-associated macrophages for cancer immunotherapy. The platform combines M1 macrophage-membrane-derived vesicles with CXCR4-binding-peptide-conjugated liposomes loaded with manganese and doxorubicin. The hybrid nanovesicles exhibited remarkable macrophage-targeting capacity through the CXCR4-binding peptide, resulting in enhanced macrophage polarization to the antitumoral M1 phenotype characterized by proinflammatory cytokine release. The manganese/doxorubicin-loaded hybrid vesicles in the CXCR4-expressing tumor cells evoked potent cancer cytotoxicity, immunogenic cell death of tumor cells, and STING activation. Moreover, cotreatment with manganese and doxorubicin promoted dendritic cell maturation, enabling effective tumor growth inhibition. In murine models of CT26 colon carcinoma and 4T1 breast cancer, intravenous administration of the manganese/doxorubicin-loaded hybrid vesicles elicited robust tumor-suppressing activity at a low dosage without adverse systemic effects. Local administration of hybrid nanovesicles also induced an abscessive effect in a bilateral 4T1 tumor model. This study demonstrates a promising biomimetic manganese/doxorubicin-based hybrid nanovesicle platform for effective cancer immunotherapy tailored to the tumor microenvironment, which may offer an innovative approach to combinatorial immunotherapy.

Peptide-drug conjugates: A new paradigm for targeted cancer therapy

Peptide-drug conjugates (PDCs) are the new hope for targeted therapy after antibody-drug conjugates (ADCs). Compared with ADCs, the core advantages of PDCs are enhanced tissue penetration, easier chemical synthesis, and lower production costs. Two PDCs have been approved by the US Food and Drug Administration (FDA) for the treatment of cancer. The therapeutic effects of PDCs are remarkable, but PDCs also encounter problems when used as targeted therapeutics, such as poor stability, a short blood circulation time, a long research and development time frame, and a slow clinical development process. Therefore, it is very urgent and important to understand the latest research progress of cancer cells targeting PDC, the solution to its stability problem, the scheme of computer technology to assist its research and development, and the direction of its future development. In this manuscript, based on the structure and function of PDCs, the latest research progress on PDCs from the aspects of cancer cell-targeting peptide (CTP) selection, pharmacokinetic characteristics, stability regulation and so on were systematically reviewed, hoping to highlight the current problems and future development directions of PDCs.

Local dose-dense chemotherapy for triple-negative breast cancer via minimally invasive implantation of 3D printed devices

Dose-dense chemotherapy is the preferred first-line therapy for triple-negative breast cancer (TNBC), a highly aggressive disease with a poor prognosis. This treatment uses the same drug doses as conventional chemotherapy but with shorter dosing intervals, allowing for promising clinical outcomes with intensive treatment. However, the frequent systemic administration used for this treatment results in systemic toxicity and low patient compliance, limiting therapeutic efficacy and clinical benefit. Here, we report local dose-dense chemotherapy to treat TNBC by implanting 3D printed devices with time-programmed pulsatile release profiles. The implantable device can control the time between drug releases based on its internal microstructure design, which can be used to control dose density. The device is made of biodegradable materials for clinical convenience and designed for minimally invasive implantation via a trocar. Dose density variation of local chemotherapy using programmable release enhances anti-cancer effects in vitro and in vivo. Under the same dose density conditions, device-based chemotherapy shows a higher anti-cancer effect and less toxic response than intratumoral injection. We demonstrate local chemotherapy utilizing the implantable device that simulates the drug dose, number of releases, and treatment duration of the dose-dense AC (doxorubicin and cyclophosphamide) regimen preferred for TNBC treatment. Dose density modulation inhibits tumor growth, metastasis, and the expression of drug resistance-related proteins, including p-glycoprotein and breast cancer resistance protein. To the best of our knowledge, local dose-dense chemotherapy has not been reported, and our strategy can be expected to be utilized as a novel alternative to conventional therapies and improve anti-cancer efficiency.

Cellular stress management by caspases

Cellular stress plays a pivotal role in the onset of numerous human diseases. Consequently, the removal of dysfunctional cells, which undergo excessive stress-induced damage via various cell death pathways, including apoptosis, is essential for maintaining organ integrity and function. The evolutionarily conserved family of cysteine-aspartic-proteases, known as caspases, has been a key player in orchestrating apoptosis. However, recent research has unveiled the capability of these enzymes to govern fundamental cellular processes without triggering cell death. Remarkably, some of these non-lethal functions of caspases may contribute to restoring cellular equilibrium in stressed cells. This manuscript discusses how caspases can function as cellular stress managers and their potential impact on human health and disease. Additionally, it sheds light on the limitations of caspase-based therapies, given our still incomplete understanding of the biology of these enzymes, particularly in non-apoptotic contexts.

Research advances in peptide‒drug conjugates

Peptide‒drug conjugates (PDCs) are drug delivery systems consisting of a drug covalently coupled to a multifunctional peptide via a cleavable linker. As an emerging prodrug strategy, PDCs not only preserve the function and bioactivity of the peptides but also release the drugs responsively with the cleavable property of the linkers. Given the ability to significantly improve the circulation stability and targeting of drugs in vivo and reduce the toxic side effects of drugs, PDCs have already been extensively applied in drug delivery. Herein, we review the types and mechanisms of peptides, linkers and drugs used to construct PDCs, and summarize the clinical applications and challenges of PDC drugs.

Curcumin and melphalan cotreatment induces cell cycle arrest and apoptosis in MDA-MB-231 breast cancer cells

Breast cancer is the second most common type of cancer worldwide and the leading cause of cancer death in women. Dietary bioactive compounds may act at different stages of carcinogenesis, including tumor initiation, promotion, and progression. Spices have been used for thousands of years and have many bioactive compounds with chemopreventive and chemotherapeutic properties. Curcumin has a multitude of beneficial biological properties, including anti-inflammatory and anticancer effects. This study investigated the effects of cotreatment with curcumin and the chemotherapeutic drug melphalan in cultured MDA-MB-231 breast cancer cells. When used alone, both curcumin and melphalan had a cytotoxic effect on breast cancer cells. Combined treatment with 11.65 µM of curcumin and 93.95 µM of melphalan (CURC/MEL) reduced cell viability by 28.64% and 72.43% after 24 h and 48 h, respectively. CURC/MEL reduced the number of colony-forming units and increased ROS levels by 1.36-fold. CURC/MEL alter cell cycle progression, induce apoptosis, and upregulate caspases-3, -7, and -9, in MDA-MB-231 cells. Cotreatment with curcumin and melphalan have anti-breast cancer cells effects and represent a promising candidate for clinical testing.

Doxorubicin prodrug-based nanomedicines for the treatment of cancer

The chemotherapeutic drug of doxorubicin (DOX) has witnessed widespread applications for treating various cancers. DOX-treated dying cells bear cellular modifications which allow enhanced presentation of tumor antigen and neighboring dendritic cell activation. Furthermore, DOX also facilitate the immune-mediated clearance of tumor cells. However, disadvantages such as severe off-target toxicity, and prominent hydrophobicity have resulted in unsatisfactory clinical therapeutic outcomes. The effective delivery of DOX drug molecules is still challenging despite the rapid advances in nanotechnology and biomaterials. Huge progress has been witnessed in DOX nanoprodrugs owing to their brilliant benefits such as tumor stimuli-responsive drug release capacity, high drug loading efficiency and so on. This review summarized recent progresses of DOX prodrug-based nanomedicines to provide deep insights into future development and inspire researchers to explore DOX nanoprodrugs with real clinical applications.

CXC Chemokine Receptor Type 4 Antagonistic Gold Nanorods Induce Specific Immune Responses and Long-Term Immune Memory to Combat Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) is highly challenging in its treatment because of the lack of the targeted markers. TNBC patients are not able to acquire benefits from endocrine therapy and targeted therapy except for chemotherapy. CXCR4 is highly expressed on TNBC cells that mediated the tumor cell metastasis as well as proliferation by the response of its ligand CXCL12, therefore holding promising potential of a candidate target for the treatment. In this work, a novel conjugate of CXCR4 antagonist peptide E5 and gold nanorods was fabricated (AuNRs-E5), which was applied to murine breast cancer tumor cells and an animal model, aiming to induce endoplasmic reticulum stress by endoplasmic reticulum-targeted photothermal immunological effects. Results showed that AuNRs-E5 could induce much more generation of damage-related molecular patterns in 4T1 cells under laser irradiation than AuNRs, which significantly promoted the maturation of dendritic cells and stimulated systematic anti-tumor immune responses by enhancing the infiltration of CD8⁺T cells into the tumor and tumor-draining lymph node, downregulating the regulatory T lymphocytes, and upregulating M1 macrophages in tumors, reversing the microenvironment from "cold" tumors to "hot" tumors. The administration of AuNRs-E5 with laser irradiation not only inhibited the tumor growth significantly but also exerted specific long immune responses to the triple-negative breast cancer tumor cells, which led to the prolonged survival of the mice and the specific immunological memory.

Bioabsorbable nano-micelle hybridized hydrogel scaffold prevents postoperative melanoma recurrence

The residual and scattered small tumor tissue or cells after surgery are the main reason for tumor recurrence. Chemotherapy has a powerful ability to eradicate tumors but always accompanied by serious side effects. In this work, tissue-affinity mercapto gelatin (GelS) and dopamine-modified hyaluronic acid (HAD) were employed to fabricate a hybridized cross-linked hydrogel scaffold (HG) by multiple chemical reactions, which could integrate the doxorubicin (DOX) loaded reduction-responsive nano-micelle (PP/DOX) into this scaffold via click reaction to obtain the bioabsorbable nano-micelle hybridized hydrogel scaffold (HGMP). With the degradation of HGMP, PP/DOX was slowly released and formed targeted PP/DOX with degraded gelatin fragments as target molecules, which increased the intracellular accumulation, and inhibited the aggregation of B16F10 cells in vitro. In mouse models, HGMP absorbed the scattered B16F10 cells and released targeted PP/DOX to suppress tumorigenesis. For another, implantation of HGMP at the surgical site reduced the recurrence rate of postoperative melanoma and inhibited the growth of recurrent tumors. Meanwhile, HGMP significantly relieved the damage of free DOX to hair follicle tissue. This bioabsorbable nano-micelle hybridized hydrogel scaffold provided a valuable strategy for adjuvant therapy after tumor surgery.

Enhancing the therapeutic efficacy of nanoparticles for cancer treatment using versatile targeted strategies

Poor targeting of therapeutics leading to severe adverse effects on normal tissues is considered one of the obstacles in cancer therapy. To help overcome this, nanoscale drug delivery systems have provided an alternative avenue for improving the therapeutic potential of various agents and bioactive molecules through the enhanced permeability and retention (EPR) effect. Nanosystems with cancer-targeted ligands can achieve effective delivery to the tumor cells utilizing cell surface-specific receptors, the tumor vasculature and antigens with high accuracy and affinity. Additionally, stimuli-responsive nanoplatforms have also been considered as a promising and effective targeting strategy against tumors, as these nanoplatforms maintain their stealth feature under normal conditions, but upon homing in on cancerous lesions or their microenvironment, are responsive and release their cargoes. In this review, we comprehensively summarize the field of active targeting drug delivery systems and a number of stimuli-responsive release studies in the context of emerging nanoplatform development, and also discuss how this knowledge can contribute to further improvements in clinical practice.