CaCO3-assistant synthesis of pH/near-infrared light-responsive and injectable sodium alginate hydrogels for melanoma synergistic treatment

Injectable tissue-engineered human cartilage matrix composite fibrin glue for regeneration of articular cartilage defects

Due to the lack of blood vessels and nerves, the ability of cartilage to repair itself is limited, and the injury of articular cartilage urgently needs effective treatment. Currently, the limitation of clinical repair for cartilage defects is that it is difficult to form pure hyaline cartilage repair, and the source of cartilage tissue and cells is limited. To obtain high-purity regenerated hyaline cartilage, we proposed to construct an injectable hydrogel precursor by using human living hyaline cartilage graft (hLhCG) secreted by human chondrocytes as the dispersed phase and fibrinogen solution as the continuous phase, by double injection with thrombin, three-dimensional network hydrogel structure was formed under the action of thrombin to repair joint defects. The component phenotypes of hLhCG and biomechanical properties of composite gel scaffolds were verified. After 12 weeks of injection of the mixed phase at the defect site, the regenerated tissues are similar in composition to adjacent natural tissues and exhibit similar biomechanical properties. The phenotype of regenerated cartilage was verified, confirming the successful regeneration of hyaline cartilage.

DDB2 promotes melanoma cell growth by transcriptionally regulating the expression of KMT2A and predicts a poor prognosis

Identification of potential key targets of melanoma, a fatal skin malignancy, is critical to the development of new cancer therapies. Lysine methyltransferase 2A (KMT2A) promotes melanoma growth by activating the human telomerase reverse transcriptase (hTERT) signaling pathway; however, the exact mechanism remains elusive. This study aimed to reveal new molecular targets that regulate KMT2A expression and melanoma growth. Using biotin-streptavidin-agarose pull-down and proteomics, we identified Damage-specific DNA-binding protein 2 (DDB2) as a KMT2A promoter-binding protein in melanoma cells and validated its role as a regulator of KMT2A/hTERT signaling. DDB2 knockdown inhibited the expression of KMT2A and hTERT and inhibited the growth of melanoma cells in vitro. Conversely, overexpression of DDB2 activated the expression of KMT2A and promoted the growth of melanoma cells. Additionally, we demonstrated that DDB2 expression was higher in tumor tissues of patients with melanoma than in corresponding normal tissues and was positively correlated with KMT2A expression. Kaplan-Meier analysis showed a poor prognosis in patients with high levels of DDB2 and KMT2A. Overall, our data suggest that DDB2 promotes melanoma cell growth through the transcriptional regulation of KMT2A expression and predicts poor prognosis. Therefore, targeting DDB2 may regulate the effects of KMT2A on melanoma growth and progression, providing a new potential therapeutic strategy for melanoma.

Advances in NIR-Responsive Natural Macromolecular Hydrogel Assembly Drugs for Cancer Treatment

Cancer is a serious disease with an abnormal proliferation of organ tissues; it is characterized by malignant infiltration and growth that affects human life. Traditional cancer therapies such as resection, radiotherapy and chemotherapy have a low cure rate and often cause irreversible damage to the body. In recent years, since the traditional treatment of cancer is still very far from perfect, researchers have begun to focus on non-invasive near-infrared (NIR)-responsive natural macromolecular hydrogel assembly drugs (NIR-NMHADs). Due to their unique biocompatibility and extremely high drug encapsulation, coupling with the spatiotemporal controllability of NIR, synergistic photothermal therapy (PTT), photothermal therapy (PDT), chemotherapy (CT) and immunotherapy (IT) has created excellent effects and good prospects for cancer treatment. In addition, some emerging bioengineering technologies can also improve the effectiveness of drug delivery systems. This review will discuss the properties of NIR light, the NIR-functional hydrogels commonly used in current research, the cancer therapy corresponding to the materials encapsulated in them and the bioengineering technology that can assist drug delivery systems. The review provides a constructive reference for the optimization of NIR-NMHAD experimental ideas and its application to human body.

An injectable, in situ forming and NIR-responsive hydrogel persistently reshaping tumor microenvironment for efficient melanoma therapy

BACKGROUND

Melanoma is a highly aggressive form of skin cancer with increasing incidence and mortality rates. Chemotherapy, the primary treatment for melanoma, is limited by hypoxia-induced drug resistance and suppressed immune response at the tumor site. Modulating the tumor microenvironment (TME) to alleviate hypoxia and enhance immune response has shown promise in improving chemotherapy outcomes.

METHODS

In this study, a novel injectable and in situ forming hydrogel named MD@SA was developed using manganese dioxide (MnO2) nanosheets pre-loaded with the chemotherapy drug doxorubicin (DOX) and mixed with sodium alginate (SA). The sustainable drug delivery, oxygen generation ability, and photothermal property of MD@SA hydrogel were characterized. The therapeutic efficacy of hydrogel was studied in B16F10 in vitro and B16F10 tumor-bearing mice in vivo. The immune effects on macrophages were analyzed by flow cytometry, real-time quantitative reverse transcription PCR, and immunofluorescence analyses.

RESULTS

The MD@SA hydrogel catalyzed the tumoral hydrogen peroxide (H2O2) into oxygen, reducing the hypoxic TME, down-regulating hypoxia-inducible factor-1 alpha (HIF-1α) and drug efflux pump P-glycoprotein (P-gp). The improved TME conditions enhanced the uptake of DOX by melanoma cells, enhancing its efficacy and facilitating the release of tumor antigens. Upon NIR irradiation, the photothermal effect of the hydrogel induced tumor apoptosis to expose more tumor antigens, thus re-educating the M2 type macrophage into the M1 phenotype. Consequently, the MD@SA hydrogel proposes an ability to constantly reverse the hypoxic and immune-inhibited TME, which eventually restrains cancer proliferation.

CONCLUSION

The injectable and in situ forming MD@SA hydrogel represents a promising strategy for reshaping the TME in melanoma treatment. By elevating oxygen levels and activating the immune response, this hydrogel offers a synergistic approach for TME regulation nanomedicine.

Biomineralized Polydopamine Nanoparticle-Based Sodium Alginate Hydrogels for Delivery of Anti-serine/Threonine Protein Kinase B-Rapidly Accelerated Fibrosarcoma siRNA for Metastatic Melanoma Therapy

Malignant melanoma, as a highly aggressive skin cancer, is strongly associated with mutations in serine/threonine protein kinase B-RAF (BRAF, where RAF stands for rapidly accelerated fibrosarcoma). Targeted therapy with anti-BRAF small interfering RNA (siBRAF) represents a crucial aspect of metastatic melanoma treatment. In this study, an injectable hydrogel platform based on sodium alginate (SA), with multifunctions of photothermal and Ca2+-overload cell apoptosis, was explored as a siBRAF carrier for metastatic melanoma therapy. We employed polydopamine nanoparticles (PDAs) as a photothermal core and constructed a calcium phosphate (CaP) shell via biomineralization (PDA@CaP) to load siBRAF (PDA@siBRAF/CaP). The pH-sensitive CaP shell facilitated the release of Ca2+ under the weakly acidic tumor microenvironment, triggering the gelation of PDA@siBRAF/CaP-SA to localized release siBRAF at tumor sites with the interruption of the RAS-RAF-MEK-ERK (MAPK) pathway. Besides, the continuous release of Ca2+ could also lead to Ca2+-overload cell apoptosis. Moreover, the photothermal effect of PDA regulated the release kinetics, resulting in coordinated therapeutic abilities of individual components in the PDA@siBRAF/CaP-SA hydrogels. Consequently, the effective inhibition of tumor growth and metastasis was achieved in vitro and in vivo using a highly metastatic melanoma cell line B16F10 as the model, by combining photothermal ablation, Ca2+ overload, and BRAF silencing. Our work provides a proof-of-concept for an injectable hydrogel system that simultaneously targets multiple mechanisms involved in melanoma progression and has the potential to be translated into clinical use for the metastatic melanoma therapy.