Gene therapy with SOCS1 induces potent preclinical antitumor activities in oral squamous cell carcinoma

Cascade Nanoreactor Employs Mitochondrial-Directed Chemodynamic and δ-ALA-Mediated Photodynamic Synergy for Deep-Seated Oral Cancer Therapy

The management of oral squamous cell carcinoma (OSCC) poses significant challenges, leading to organ impairment and ineffective treatment of deep-seated tumors, adversely affecting patient prognosis. A cascade nanoreactor that integrates photodynamic therapy (PDT) and chemodynamic therapy (CDT) for comprehensive multimodal OSCC treatment is introduced. Utilizing iron oxide and mesoporous silica, the FMMSH drug delivery system, encapsulating the photosensitizer prodrug δ-aminolevulinic acid (δ-ALA), is developed. Triphenylphosphine (TPP) modification facilitates mitochondrial targeting, while tumor cell membrane (TCM) coating provides homotypic targeting. The dual-targeting δ-ALA@FMMSH-TPP-TCM demonstrate efficacy in eradicating both superficial and deep tumors through synergistic PDT/CDT. Esterase overexpression in OSCC cells triggers δ-ALA release, and excessive hydrogen peroxide in tumor mitochondria undergoes Fenton chemistry for CDT. The synergistic interaction of PDT and CDT increases cytotoxic ROS levels, intensifying oxidative stress and enhancing apoptotic mechanisms, ultimately leading to tumor cell death. PDT/CDT-induced apoptosis generates δ-ALA-containing apoptotic bodies, enhancing antitumor efficacy in deep tumor cells. The anatomical accessibility of oral cancer emphasizes the potential of intratumoral injection for precise and localized treatment delivery, ensuring focused therapeutic agent delivery to maximize efficacy while minimizing side effects. Thus, δ-ALA@FMMSH-TPP-TCM, tailored for intratumoral injection, emerges as a transformative modality in OSCC treatment.

TRIM8 Promotes Proliferation, Invasion, and Migration of Cervical Cancer Cells by Ubiquitinating and Degrading SOCS1

Cervical cancer (CC) is a malignant tumor primarily caused by the persistent infection with high-risk strains of human papillomavirus. This study investigates the aberrant expression of Tripartite Motif Containing 8 (TRIM8) in CC and its impact on cell proliferation, invasion, and migration. Expression levels of TRIM8, Proliferating Cell Nuclear Antigen, and Suppressor of Cytokine Signaling 1 (SOCS1) were assessed in CC cell lines. CC cells were transfected with si-TRIM8, followed by cell counting kit-8 (CCK-8) assay, colony formation assay, and Transwell assay. Protein immunoprecipitation assay was employed to examine TRIM8's binding with SOCS1, and the ubiquitination level of SOCS1 was determined after MG132 treatment. Rescue experiments were conducted using si-SOCS1 and si-TRIM8 in combination. Results indicate upregulation of TRIM8 in CC cells. Inhibition of TRIM8 suppressed cell viability, proliferation, invasion, and migration. TRIM8 promoted CC cell proliferation, invasion, and migration of CC cells through ubiquitination-mediated degradation of SOCS1. Inhibition of SOCS1 partially reversed the inhibitory effects of si-TRIM8 on the proliferation, invasion, and migration of CC cells. In conclusion, TRIM8 enhances CC cell proliferation, invasion, and migration via ubiquitination-mediated degradation of SOCS1.

Systemic and Local Administration of a Dual-siRNA Complex Efficiently Inhibits Tumor Growth and Bone Invasion in Oral Squamous Cell Carcinoma

Oral squamous cell carcinoma (OSCC) accounts for nearly 90% of oral and oropharyngeal cancer cases and is characterized by high mortality and poor prognosis. RNA-based gene therapies have been developed as an emerging option for cancer treatment, but it has not been widely explored in OSCC. In this work, we developed an efficient siRNA cationic micelle DOTAP-mPEG-PCL (DMP) by self-assembling the cationic lipid DOTAP and monomethoxy poly(ethylene glycol)-poly(ε-caprolactone) (mPEG-PCL) polymer. We tested the characteristics and transformation efficiency of this micelle and combined DMP with siRNA targeting STAT3 and TGF-β to evaluate the antitumor effect and bone invasion interfering in vitro and in vivo. The average size of the DMP was 28.27 ± 1.62 nm with an average zeta potential of 54.60 ± 0.29 mV. The DMP/siRNA complex showed high delivery efficiency, with rates of 97.47 ± 0.42% for HSC-3. In vitro, the DMP/siSTAT3 complex exhibited an obvious cell growth inhibition effect detected by MTT assay (an average cell viability of 25.1%) and clonogenic assay (an average inhibition rate of 51.9%). Besides, the supernatant from HSC-3 transfected by DMP/siTGF-β complexes was found to interfere with osteoclast differentiation in vitro. Irrespective of local or systemic administration, DMP/siSTAT3+siTGF-β showed antitumor effects and bone invasion inhibition in the OSCC mice mandibular invasion model according to tumor volume assays and Micro-CT scanning. The complex constructed by DMP cationic micelles and siSTAT3+siTGF-β represents a potential RNA-based gene therapy delivery system for OSCC.

Network pharmacology and experiment validation investigate the potential mechanism of triptolide in oral squamous cell carcinoma

Objective: This study aimed to investigate the molecular mechanism of triptolide in the treatment of oral squamous cell carcinoma (OSCC) via network pharmacology and experimental validation. Methods: The network pharmacological method was used to predict the key targets, detect the signal pathways for the treatment of OSCC, and screen the critical components and targets for molecular docking. Predicted targets were validated in cellular and xenograft mouse model. Results: In this study, we predicted action on 17 relevant targets of OSCC by network pharmacology. PPI network demonstrated that Jun, MAPK8, TP53, STAT3, VEGFA, IL2, CXCR4, PTGS2, IL4 might be the critical targets of triptolide in the treatment of OSCC. These potential targets are mainly closely related to JAK-STAT and MAPK signaling pathways. The analysis of molecular docking showed that triptolide has high affinity with Jun, MAPK8 and TP53. Triptolide can suppress the growth of OSCC cells and xenograft mice tumor, and downregulate the expression of Jun, MAPK8, TP53, STAT3, VEGFA, IL2, CXCR4, PTGS2 to achieve the therapeutic effect of OSCC. Conclusion: Through network pharmacological methods and experimental studies, we predicted and validated the potential targets and related pathways of triptolide for OSCC treatment. The results suggest that triptolide can inhibit the growth of OSCC via several key targets.

Ad-hoc modifications of cyclic mimetics of SOCS1 protein: Structural and functional insights

Suppressors of cytokine signaling 1 (SOCS1) protein, a negative regulator of the Janus kinase (JAK)-signal transducer and activator of transcription (STAT) pathway, possesses a small kinase inhibitory region (KIR) involved in the inhibition of JAK kinases. Several studies showed that mimetics of KIR-SOCS1 can be potent therapeutics in several disorders (e.g., neurological, autoimmune or cardiovascular diseases). In this work, starting from a recently identified cyclic peptidomimetic of KIR-SOCS1, icPS5(Nal1), to optimize the peptide structure and improve its biological activity, we designed novel derivatives, containing crucial amino acids substitutions and/or modifications affecting the ring size. By combining microscale thermophoresis (MST), Circular Dichroism (CD), Nuclear Magnetic Resonance (NMR) and computational studies, we showed that the cycle size plays a key role in the interaction with JAK2 and the substitution of native residues with un-natural building blocks is a valid tool to maintain low-micromolar affinity toward JAK2, greatly increasing their serum stability. These findings contribute to increase the structural knowledge required for the recognition of SOCS1/JAK2 and to progress towards their conversion into more drug-like compounds.