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Abstract Since the United States Food and Drug Administration (FDA) approved the first chimeric antigen receptor T-cell (CAR-T) therapy in 2017, it has marked a major breakthrough in cancer treatment, leading to a surge in global research and applications in this field. In recent years, China has made rapid progress, quickly catching up through heavy investment in CAR-T construction, preparation processes, and treatment strategies. China’s CAR-T therapy market is driven by substantial pharmaceutical investment targeting its vast population, yet high therapy costs remain uncovered by basic medical insurance. In November 2023, FDA issued a warning about the risk of secondary cancers in patients undergoing CAR-T therapy, sparking global concern. In fact, the China National Medical Products Administration (NMPA) preemptively implemented a series of measures to address the safety concerns of CAR-T therapy, emphasizing the risk of secondary cancers and advising lifelong monitoring as part of the approval process for CAR-T products. Nevertheless, additional regulatory measures are needed to address emerging risks, particularly the threat of secondary cancers. The authors believe that raising the standards for Investigational New Drug (IND) approval and establishing a dynamic reporting and feedback system based on real-world data will strengthen regulatory oversight and support the sustainable growth of the CAR-T industry in China.

Abstract The current selection of ligands for both proteins of interest (POI) and E3 ubiquitin ligase significantly restricts the scope of targeted protein degradation (TPD) technologies. This study introduces cell-penetrating peptide-induced chimera conjugates (cp-PCCs) targeting the DHHC3 enzyme involved in PD-L1 palmitoylation. This approach disrupts PD-L1’s immunosuppressive function, enhancing anti-tumor immunity. We developed cp-PCCs to degrade DHHC3, directly linking DHHC3-mediated PD-L1 palmitoylation to PD-L1 stability on tumor cells. Our research utilized both in vitro assays and in vivo experiments in immune checkpoint blockade-resistant mouse models. We focused on a CRBN-based cp-PCC named PCC16, which demonstrated a DC50 of 102 nmol for DHHC3 degradation and significantly reduced PD-L1 levels. In resistant models, PCC16 not only robustly downregulated PD-L1 but also exhibited substantial anti-tumor activity in vivo without significant toxicity. This outperformed traditional inhibitors, showcasing the potential of cp-PCC technology to bypass current PROTAC limitations. Our findings suggest that cp-PCCs offer a promising method for targeting PD-L1 through DHHC3 inhibition and support their continued exploration as a versatile tool in cancer immunotherapy, especially for tumors resistant to standard treatments.

IntroductionOur previous research has found that degradation of palmitoyltransferase in tumor cells using a linear peptide PROTAC leads to a significant decrease in PD-L1 expression in tumors. However, this degradation is not a sustained and efficient process. Therefore, we designed a cyclic peptide PROTAC to achieve this efficient anti-PD-L1 effect.MethodsWe designed and synthesized an improvement in linear peptide PROTAC targeting palmitoyltransferase DHHC3, and used disulfide bonds to stabilize the continuous N- and C-termini of the peptides to maintain their structure. Cellular and molecular biology techniques were used to test the effect of this cyclic peptide on PD-L1.ResultsIn human cervical cancer cells, our cyclic peptide PROTAC can significantly downregulate palmitoyl transferase DHHC3 and PD-L1 expressions. This targeted degradation effect is enhanced with increasing doses and treatment duration, with a DC50 value much lower than that of linear peptides. Additionally, flow cytometry analysis of fluorescence intensity shows an increase in the amount of cyclic peptide entering the cell membrane with prolonged treatment time and higher concentrations. The Cellular Thermal Shift Assay (CETSA) method used in this study indicates effective binding between our novel cyclic peptide and DHHC3 protein, leading to a change in the thermal stability of the latter. The degradation of PD-L1 can be effectively blocked by the proteasome inhibitor MG132. Results from clone formation experiments illustrate that our cyclic peptide can enhance the proliferative inhibition effect of cisplatin on the C33A cell line. Furthermore, in the T cell-C33A co-culture system, cyclic peptides target the degradation of PD-L1, thereby blocking the interaction between PD-L1 and PD-1, and promoting the secretion of IFN-γ and TNF-α in the co-culture system supernatant.ConclusionOur results demonstrate that a disulfide-bridged cyclic peptide PROTAC targeting palmitoyltransferase can provide a stable and improved anti-PD-L1 activity in human tumor cells.

IntroductionImmune checkpoint inhibitors (ICIs) are monoclonal antibodies that target immune checkpoints that suppress immune cell activity. Low efficiency and high resistance are currently the main barriers to their clinical application. As a representative technology of targeted protein degradation, proteolysis-targeting chimeras (PROTACs) are considered to have potential for addressing these limitations.MethodsWe synthesized a stapled peptide-based PROTAC (SP-PROTAC) that specifically targeted palmitoyltransferase ZDHHC3 and resulted in the decrease of PD-L1 in human cervical cancer cell lines. Flow cytometry, confocal microscopy, protein immunoblotting, Cellular Thermal Shift Assay (CETSA), and MTT assay analyses were conducted to evaluate the effects of the designed peptide and verify its safety in human cells.ResultsIn cervical cancer celllines C33A and HeLa, the stapled peptide strongly downregulated PD-L1 to < 50% of baseline level at 0.1 μM. DHHC3 expression decreased in both dosedependentand time-dependent manners. MG132, the proteasome inhibitor, can alleviate the SP-PROTAC mediated degradation of PD-L1 in human cancer cells. In a co-culture model of C33A and T cells, treatment with the peptide induced IFN-γ and TNF-α release in a dose-dependent manner by degrading PD-L1. These effects were more significant than that of the PD-L1 inhibitor, BMS-8.ConclusionsCells treated with 0.1 μM of SP-PROTAC or BMS-8 for 4 h revealed that the stapled peptide decreased PD-L1 more effectively than BMS-8. DHHC3-targeting SP-PROTAC decreased PD-L1 in human cervical cancer more effectively than the inhibitor BMS-8.

Abstract Background Influenza A virus (IAV) triggers acute exacerbation of chronic obstructive pulmonary disease (AECOPD), but the molecular mechanisms remain unclear. In this study, we investigated the role of IAV induced NLRP3 inflammasome activation to increase airway inflammation response in the progression of AECOPD. Methods Human bronchial epithelial cells were isolated and cultured from normal and COPD bronchial tissues and co-cultured with IAV. The NLRP3 inflammasome associated genes were identified using RNA sequencing, and the expressions of NLRP3 inflammasome components were measured using qRT-PCR and western blot after cells were transfected with siRNA and treated with MCC950. Moreover, IAV-induced COPD rat models were established to confirm the results; 37 AECOPD patients were included to measure the serum and bronchoalveolar lavage fluid (BALF) of interleukin (IL)-18 and IL-1β. Results Increased levels of NLRP3 inflammasome components were not seen until 6 h post-inoculation in normal cells. However, both cell groups reached peak NLRP3 level at 12 h post-inoculation and maintained it for up to 24 h. ASC, Caspase-1, IL-1β and IL-18 were also elevated in a similar time-dependent pattern in both cell groups. The mRNA and protein expression of the NLRP3 inflammasome components were decreased when COPD cells treated with siRNA and MCC950. In COPD rats, the NLRP3 inflammasome components were elevated by IAV. MCC950 alleviated lung damage, improved survival time, and reduced NLRP3 inflammasome components expression in COPD rats. Additionally, the serum and BALF levels of IL-1β and IL-18 were increased in AECOPD patients. Conclusions NLRP3 inflammasome is activated in COPD patients as a pre-existing condition that is further exacerbated by IAV infection.

Immune checkpoint inhibitors have made significant progress in the treatment of various cancers. However, due to the low ICI responsive rate for the gynecologic cancer, ICI two-drug combination therapy tends to be a predominant way for clinical treatment. Antibody-drug conjugates, a promising therapeutic modality for cancer, have been approved by the FDA for breast cancer, lymphoma, multiple myeloma and gastric cancer. On September 2021, the FDA granted accelerated approval to tisotumab vedotin for patients with recurrent or metastatic cervical cancer. Currently, the role of therapy of ADCs on gynecologic tumors was also included in medication regimens. Now more than 30 ADCs targeting for 20 biomarkers are under clinical trials in the field, including monotherapy or combination with others for multiple lines of therapy. Some ADCs have been proved to enhance the antitumor immunity effect on both pre-clinical models and clinical trials. Therefore, combination of ADCs and ICIs are expected in clinical trials. In this review, we discuss current development of ADCs in gynecologic oncology and the combination effects of ICIs and ADCs.

Background: Shufeng Jiedu (SFJD) capsules can be used as adjunctive treatment for patients with community-acquired pneumonia, but the effectiveness and safety of SFJD are not clear. This review aims to evaluate the effectiveness and safety of SFJD based on randomized controlled trials (RCTs).Methods: A systematic review was conducted by searching PubMed, Embase, Scopus, Web of Science, CENTRAL, CNKI, VIP, CBM, Wanfang and trial registry platforms from their inception to March 2022. Two reviewers screened studies, extracted the data and assessed risk of bias independently. The data were pooled for meta-analysis or presented narratively.Results: Seventeen RCTs involving 1840 participants were included. All trials compared SFJD plus antibiotics to antibiotics, or combined with symptomatic treatment in both groups. The overall certainty of evidence was assessed as moderate to very low certainty. Compared with routine treatment (antibiotics alone or antibiotics plus symptomatic treatment), SFJD plus routine treatment showed beneficial effects in resolution of fever (MD −1.20 days, 95%CI −1.73 to −0.67; 10 RCTs; very low certainty), cough (MD −1.02 days, 95%CI −1.23 to −0.81; 9 RCTs; moderate certainty), phlegm (MD −1.46 days, 95%CI −2.84 to −0.08; 6 RCTs; very low certainty), pulmonary crepitations (MD −1.61 days, 95%CI −2.64 to −0.59; 8 RCTs; low certainty), shortness of breath (MD −2.80 days, 95%CI −2.88 to −2.72; 2 RCTs; low certainty) and chest pain (MD −2.85 days, 95%CI −3.01 to −2.69; 1 RCT; low certainty). There was no significant difference in pathogen clearance (1 RCT). No serious adverse events were reported, but 2.60% (5/192) patients reported nausea in the SFJD groups, 1.04% (2/192) participants in routine group, and no significant difference was identified.Conclusions: Current evidence suggests that adding SFJD may shorten the duration of symptom relief in community-acquired pneumonia for 1–2 days. The adverse events were minor and controllable, and no serious adverse events were reported. Well-reported trials and potential of reducing antibiotics were expected in the future studies.