Cell-penetrating peptides TAT and 8R functionalize P22 virus-like particles to enhance tissue distribution and retention in vivo.

Virus-like particles (VLPs) are used as nanocontainers for targeted drug, protein, and vaccine delivery. The phage P22 VLP is an ideal macromolecule delivery vehicle, as it has a large exterior surface area, which facilitates multivalent genetic and chemical modifications for cell recognition and penetration. Arginine-rich cell-penetrating peptides (CPPs) can increase cargo transport efficiency in vivo. However, studies on the tissue distribution and retention of P22 VLPs mediated by TAT and 8R are lacking. This study aimed to analyze the TAT and 8R effects on the P22 VLPs transport efficiency and tissue distribution both in vitro and in vivo. We used a prokaryotic system to prepare P22 VLP self-assembled particles and expressed TAT-or 8R-conjugated mCherry on the VLP capsid protein as model cargoes and revealed that the level of P22 VLP-mCherry penetrating the cell membrane was low. However, both TAT and 8R significantly promoted the cellular uptake efficiency of P22 VLPs in vitro, as well as enhanced the tissue accumulation and retention of P22 VLPs in vivo. At 24 h postinjection, TAT enhanced the tissue distribution and retention in the lung, whereas 8R could be better accumulation in brain. Thus, TAT was superior in terms of cellular uptake and tissue accumulation in the P22 VLPs delivery system. Understanding CPP biocompatibility and tissue retention will expand their potential applications in macromolecular cargo delivery.

Long-term outcomes and prognosis of neuroendocrine neoplasms of the head and neck: a cohort from a single institution.

BACKGROUND: Neuroendocrine neoplasm is a rare cancer of head and neck. This study aimed to evaluate clinical features, treatment outcomes, and prognostic factors of neuroendocrine neoplasm of head and neck treated at a single institution. METHODS: Between Nov 2000 and Nov 2021, ninety-three patients diagnosed with neuroendocrine neoplasms of head and neck treated at our institution were reviewed retrospectively. The initial treatments included chemotherapy (induction, adjuvant, or concurrent) combined with radiotherapy in 40 patients (C + RT group), surgery followed by post-operative RT in 34 (S + RT group), and surgery plus salvage therapy in 19 patients (S + Sa group). RESULTS: The median follow-up time was 64.5 months. 5-year overall survival rate (OS), progression-free survival rate (PFS), loco-regional relapse-free survival free rate (LRRFS) and distant metastasis-free survival rate (DMFS) were 64.5%, 51.6%, 66.6%, and 62.1%, respectively. For stage I-II, the 5-year LRRFS for patients' treatment regimen with or without radiotherapy (C + RT and S + RT groups versus S + Sa group) was 75.0% versus 12.7% (p = 0.015) while for stage III-IV, the 5-year LRRFS was 77.8% versus 50.0% (p = 0.006). The 5-year DMFS values for patients with or without systemic therapy (C + RT group versus S + RT or S + Sa) were 71.2% and 51.5% (p = 0.075). 44 patients (47.3%) experienced treatment failure and distant metastasis was the main failure pattern. CONCLUSIONS: Radiotherapy improved local-regional control and played an important role in the management of HNNENs. The optimal treatment regimen for HNNENs remains the combination of local and systemic treatments.

Identification of a linear B-cell epitope on the "puff" loop of the Senecavirus A VP2 protein involved in receptor binding.

Senecavirus A (SVA) is an important emerging swine pathogen that causes vesicular lesions in swine and acute death in newborn piglets. VP2 plays a significant role in the production of antibodies, which can be used in development of diagnostic tools and vaccines. Herein, the aim of the current study was to identify B-cell epitopes (BCEs) of SVA for generation of epitope-based SVA marker vaccine. Three monoclonal antibodies (mAbs), named 2E4, 1B8, and 2C7, against the SVA VP2 protein were obtained, and two novel linear BCEs, 177SLGTYYR183 and 266SPYFNGL272, were identified by peptide scanning. The epitope 177SLGTYYR183 was recognized by the mAb 1B8 and was fully exposed on the VP2 surface, and alanine scanning analysis revealed that it contained a high continuity of key amino acids. Importantly, we confirmed that 177SLGTYYR183 locates on "the puff" region within the VP2 EF loop, and contains three key amino acid residues involved in receptor binding. Moreover, a single mutation, Y182A, blocked the interaction of the mutant virus with the mAb 1B8, indicating that this mutation is the pivotal point for antibody recognition. In summary, the BCEs that identified in this study could be used to develop diagnostic tools and an epitope-based SVA marker vaccine.

Spatial architecture of regulatory T-cells correlates with disease progression in patients with nasopharyngeal cancer.

Purpose: This study aims to investigate the prognostic value of composition and spatial architecture of tumor-infiltrating lymphocytes (TILs) as well as PDL1 expression on TILs subpopulations in nasopharyngeal carcinoma (NPC). Methods: A total of 121 patients with NPC were included and divided into two groups: favorable (n = 68) and unfavorable (n = 53). The archived tumor tissues of the included patients were retrieved, and a tissue microarray was constructed. The density and spatial distribution of TILs infiltration were analyzed using the multiplex fluorescent immunohistochemistry staining for CD3, CD4, CD8, Foxp3, cytokeratin (CK), PDL1, and 4',6-diamidino-2-phenylindole (DAPI). The infiltration density of TILs subpopulations and PDL1 expression were compared between the two groups. The Gcross function was calculated to quantify the relative proximity of any two types of cells. The Cox proportional hazards regression model was used to identify factors associated with overall survival (OS) and disease-free survival (DFS). Results: The densities of regulatory T-cells (Tregs), effector T-cells (Teffs), PDL1+ Tregs, and PDL1+ Teffs were significantly higher in patients with unfavorable outcomes. PDL1 expression on tumor cells (TCs) or overall TILs was not associated with survival. Multivariate analysis revealed that higher PDL1+ Tregs infiltration density was independently associated with inferior OS and DFS, whereas Tregs infiltration density was only a prognostic marker for DFS. Spatial analysis revealed that unfavorable group had significantly stronger Tregs and PDL1+ Tregs engagement in the proximity of TCs and cytotoxic T lymphocyte (CTLs). Gcross analysis further revealed that Tregs and PDL1+ Tregs were more likely to colocalize with CTLs. Moreover, increased GTC : Treg (Tregs engagement surrounding TCs) and GCTL : PDL1+ Treg were identified as independent factors correlated with poor outcomes. Conclusion: TILs have a diverse infiltrating pattern and spatial distribution in NPC. Increased infiltration of Tregs, particularly PDL1+ Tregs, as well as their proximity to TCs and CTLs, correlates with unfavorable outcomes, implying the significance of intercellular immune regulation in mediating disease progression.

Role of adjuvant (chemo)radiotherapy for resected extrahepatic cholangiocarcinoma: a meta-analysis.

BACKGROUND: Adjuvant (chemo)radiotherapy (A(C)RT) may be an important supplement to surgery for extrahepatic cholangiocarcinoma (EHCC). However, whether all patients would achieve benefits from A(C)RT and which adjuvant regimen, adjuvant radiotherapy (ART) or adjuvant chemoradiotherapy (ACRT), would be preferred, are still undetermined. The low incidence of EHCC makes it difficult to carry out randomized controlled trials (RCTs); therefore, almost all clinical studies on radiotherapy are retrospective. We have conducted a meta-analysis of these retrospective studies. METHODS: We conducted a meta-analysis of current retrospective studies using PubMed, Embase, and ClinicalTrials databases. All studies published in English that were related to A(C)RT and which analyzed overall survival (OS), disease-free survival (DFS), or locoregional recurrence-free survival (LRFS) were included. Estimated hazard ratios (HRs) were calculated for OS, DFS, and LRFS. RESULTS: Data from eight studies including 685 patients were included. Our analysis showed that A(C)RT significantly improved OS (HR 0.69, 95% confidence interval (CI) 0.48-0.97, P=0.03), DFS (HR 0.60, 95% CI 0.47-0.76, P<0.0001), and LRFS (HR 0.27, 95% CI 0.17-0.41, P<0.00001) of EHCC overall. In subgroups, patients with microscopically positive resection margin (R1) could achieve a benefit from A(C)RT (HR 0.44, 95% CI 0.27-0.72, P=0.001). No statistically OS difference was observed in negative resection margin (R0) subgroup (HR 0.98, 95% CI 0.30-3.19, P=0.98).Significant OS benefit was found in patients who received concurrent ACRT (HR 0.40, 95% CI 0.26-0.62, P<0.0001), while the result of ART without chemotherapy showed no significant benefit (HR 1.14, 95% CI 0.29-4.50, P=0.85). In the distal cholangiocarcinoma subgroup, no significant difference was seen when ACRT and ART were included (HR 0.61, 95% CI 0.14-2.72, P=0.52), but a significant difference was seen when analyzing the concurrent ACRT only (HR 0.29, 95% CI 0.13-0.64, P=0.002). CONCLUSIONS: A(C)RT may improve OS, DFS, and LRFS in EHCC patients, especially in those with R1 resection margins. ACRT may be superior to ART especially in distal patients.

Radiotherapy for one rectal cancer patient with cirrhosis and moderate to severe thrombocytopenia: a case report.

When patients with cirrhosis and severe thrombocytopenia suffer malignant tumors, there is usually no effective and feasible treatment method due to the high risk of hemorrhage. Herein, we report a case in which radiotherapy was given to a patient with a strong desire for the treatment. The patient was a 66-year-old man with a 13-year history of cirrhosis and a 10-year history of thrombocytopenia, and was diagnosed with locally advanced rectal cancer (LARC; T4aN1M0, stage IIIB). The platelet count before radiotherapy was 32 × 109/L, and the blood coagulation was normal. The severity of thrombocytopenia increased after 2 Gy × 7 fractions pelvic radiation, with platelet counts dropping to 16 × 109/L. Platelet counts failed to return to pre-therapy levels after supporting therapy including recombinant human interleukin 11 subcutaneous injection and platelet transfusion. Although radiotherapy was discontinued eventually, the data presented here represent a valuable resource that can help inform treatment decisions for tumor patients with cirrhosis and thrombocytopenia.