Site-selective antibody-lipid conjugates for surface functionalization of red blood cells and targeted drug delivery.

Displaying antibodies on carrier surfaces facilitates precise targeting and delivery of drugs to diseased cells. Here, we report the synthesis of antibody-lipid conjugates (ALCs) through site-selective acetylation of Lys 248 in human Immunoglobulin G (IgG) and the development of antibody-functionalized red blood cells (immunoRBC) for targeted drug delivery. ImmunoRBC with the HER2-selective antibody trastuzumab displayed on the surface (called Tras-RBC) was constructed following a three-step procedure. First, a peptide-guided, proximity-induced reaction transferred an azidoacetyl group to the ε-amino group of Lys 248 in the Fc domain. Second, the azide-modified IgG was subsequently conjugated with dibenzocyclooctyne (DBCO)-functionalized lipids via strain-promoted azide-alkyne cycloaddition (SPAAC) to result in ALCs. Third, the lipid portion of ALCs was then inserted into the cell membranes, and IgGs were displayed on red blood cells (RBCs) to construct immunoRBCs. We then loaded Tras-RBC with a photosensitizer (PS), Zinc phthalocyanine (ZnPc), to selectively target HER2-overexpressing cells, release ZnPc into cancer cells following photolysis, and induce photodynamic cytotoxicity in the cancer cells. This work showcases assembling immunoRBCs following site-selective lipid conjugation on therapeutic antibodies and the targeted introduction of PS into cancer cells. This method could apply to the surface functionalization of other membrane-bound vesicles or lipid nanoparticles for antibody-directed drug delivery.

Endoscopic incisional therapy for benign anastomotic strictures after esophagectomy or gastrectomy: a systematic review and meta-analysis.

BACKGROUND: Studies have evaluated the efficacy of endoscopic incisional therapy (EIT) for benign anastomotic strictures. We performed a systematic review and meta-analysis to evaluate stricture recurrence after EIT following esophagectomy or gastrectomy. METHODS: A systematic search of databases was performed up to April 2nd, 2023, after selection of key search terms with the research team. Inclusion criteria included human participants undergoing EIT for a benign anastomotic stricture after esophagectomy or gastrectomy, age ≥ 18, and n ≥ 5. Our primary outcome was the incidence of stricture recurrence among patients treated with EIT compared to dilation. Our secondary outcome was the stricture-free duration after EIT and rate of adverse events. Meta-analysis was performed with RevMan 5.4.1 using a Mantel-Haenszel random-effects model. Publication bias was evaluated with funnel plots and the Egger test. RESULTS: A total of 2550 unique preliminary studies underwent screening of abstracts and titles. This led to 33 studies which underwent full-text review and five studies met the inclusion criteria. Meta-analysis revealed reduced odds of overall stricture recurrence (OR 0.35, 95% CI 0.13-0.92, p = 0.03; I2 = 71%) and reduced odds of stricture recurrence among naïve strictures (OR 0.32, 95% CI 0.17-0.59, p = 0.0003; I2 = 0%) for patients undergoing EIT compared to dilation. There was no significant difference in the odds of stricture recurrence among recurrent strictures (OR 0.63, 95% CI 0.12-3.28, p = 0.58; I2 = 81%). Meta-analysis revealed a significant increase in the recurrence-free duration (MD 42.76, 95% CI 12.41-73.11, p = 0.006) among patients undergoing EIT compared to dilation. CONCLUSION: Current data suggest EIT is associated with reduced odds of stricture recurrence among naïve anastomotic strictures. Large, prospective studies are needed to characterize the safety profile of EIT, address publication bias, and to explore multimodal therapies for refractory strictures.

A new invertebrate NPY-like polypeptide, ZoaNPY, from the Zoanthus sociatus, as a novel ligand of human NPY Y2 receptor rescues vascular insufficiency via PLC/PKC and Src- FAK-dependent signaling pathways.

Our recent multi-omics studies have revealed rich sources of novel bioactive proteins and polypeptides from marine organisms including cnidarians. In the present study, we initially conducted a transcriptomic analysis to review the composition profile of polypeptides from Zoanthus sociatus. Then, a newly discovered NPY-like polypeptide-ZoaNPY was selected for further in silico structural, binding and virtually pharmacological studies. To evaluate the pro-angiogenic effects of ZoaNPY, we employed an in vitro HUVECs model and an in vivo zebrafish model. Our results indicate that ZoaNPY, at 1-100 pmol, enhances cell survival, migration and tube formation in the endothelial cells. Besides, treatment with ZoaNPY could restore a chemically-induced vascular insufficiency in zebrafish embryos. Western blot results demonstrated the application of ZoaNPY could increase the phosphorylation of proteins related to angiogenesis signaling including PKC, PLC, FAK, Src, Akt, mTOR, MEK, and ERK1/2. Furthermore, through molecular docking and surface plasmon resonance (SPR) verification, ZoaNPY was shown to directly and physically interact with NPY Y2 receptor. In view of this, all evidence showed that the pro-angiogenic effects of ZoaNPY involve the activation of NPY Y2 receptor, thereby activating the Akt/mTOR, PLC/PKC, ERK/MEK and Src- FAK-dependent signaling pathways. Furthermore, in an excision wound model, the treatment with ZoaNPY was shown to accelerate the wound healing process in mice. Our findings provide new insights into the discovery and development of novel pro-angiogenic drugs derived from NPY-like polypeptides in the future.

A population-based analysis of the impact of 1 vs. 2 doses of mitomycin on patterns of failure of anal cancer patients treated with concurrent chemoradiotherapy.

PURPOSE: We report the impact of 1 vs. 2 doses of mitomycin-C (MMC) based chemoradiation (CRT) on patterns of treatment failure and long-term patient outcomes in anal squamous cell carcinoma (ASCC) and the predictors for locoregional failure (LRF) and distant metastasis (DM). METHODS: In this population-based study, we identified all patients with anal cancer in our province treated radically with radiation and concurrent 5-Fluorouracil (5FU) and 1 vs. 2 doses of MMC between the years 2000-2019. The primary outcomes analyzed were locoregional recurrence (LRR), disease free survival (DFS), ASCC cancer-specific survival (ASCC-CSS) and overall survival (OS). RESULTS: 451 patients were identified. 272 (60%) patients received 1 cycle of MMC (MMC1) and 179 (40%) received 2 cycles (MMC2) as part of the CRT regimen. The median follow-up was 57 (36-252) and 97 (38-239) months for MMC1 and MMC2, respectively. Cox Regression analysis showed stage IIIb and IIIc were associated with worse locoregional recurrence free survival (RFS) (HR=2.851, p=<0.001) and distant RFS (HR=3.391, p=<0.001). Similarly, stage IIIb and IIIc patients had poorer DFS (HR 3.439, p=<0.001), ASCC-SS (HR 3.729, p=<0.001) and OS (2.230, p=<0.001). The use of MMC2 showed a positive impact on improved ASCC-SS (HR 0.569, p=0.029) and distant RFS (HR 0.555, p=0.040) in patients with stage IIIb and IIIc. CONCLUSIONS: Our analysis showed that 1 vs. 2 cycles of MMC along with 5FU and radiation is associated with comparable treatment outcomes in general. However, in patients with stage IIIb and IIIc cancer, 2 doses of MMC were associated with improved ASCC-SS and distant DFS.

Chemical Modification of Cytochrome C for Acid-Responsive Intracellular Apoptotic Protein Delivery for Cancer Eradication.

Delivering bioactive proteins into cells without carriers presents significant challenges in biomedical applications due to limited cell membrane permeability and the need for targeted delivery. Here, we introduce a novel carrier-free method that addresses these challenges by chemically modifying proteins with an acid-responsive cell-penetrating peptide (CPP) for selective intracellular delivery within tumours. Cytochrome C, a protein known for inducing apoptosis, served as a model for intracellular delivery of therapeutic proteins for cancer treatment. The CPP was protected with 2,3-dimethyl maleic anhydride (DMA) and chemically conjugated onto the protein surface, creating an acid-responsive protein delivery system. In the acidic tumour microenvironment, DMA deprotects and exposes the positively charged CPP, enabling membrane penetration. Both in vitro and in vivo assays validated the pH-dependent shielding mechanism, demonstrating the modified cytochrome C could induce apoptosis in cancer cells in a pH-selective manner. These findings provide a promising new approach for carrier-free and tumour-targeted intracellular delivery of therapeutic proteins for a wide range of potential applications.

Detection and Elimination of Senescent Cells with a Self-Assembled Senescence-Associated ß-Galactosidase-Activatable Nanophotosensitizer.

Senescent cells have become an important therapeutic target for many age-related dysfunctions and diseases. We report herein a novel nanophotosensitizing system that is responsive to the senescence-associated ß-galactosidase (ß-gal) for selective detection and elimination of these cells. It involves a dimeric zinc(II) phthalocyanine linked to a ß-galactose unit via a self-immolative linker. This compound can self-assemble in aqueous media, forming stable nanoscale particles in which the phthalocyanine units are stacked and self-quenched for fluorescence emission and singlet oxygen production. Upon internalization into senescent HeLa cells, these nanoparticles interact with the overproduced senescence-associated ß-gal inside the cells to trigger the disassembly process through enzymatic cleavage of the glycosidic bonds, followed by self-immolation to release the photoactive monomeric phthalocyanine units. These senescent cells can then be lit up with fluorescence and eliminated through the photodynamic action upon light irradiation with a half-maximal inhibitory concentration of 0.06 µM.

Breaking Down Barriers to Detection and Care in Early-Age-Onset Colorectal Cancer in Canada.

The second Early-Age-Onset Colorectal Cancer Symposium, convened in October 2022, sought solutions to the barriers to early detection and care for colorectal cancer in Canada. This meeting built on a previous symposium, held in 2021 and reported in this journal. Early-age-onset colorectal cancer (EAOCRC) affects increasing numbers of people under the age of 50 in Canada and throughout the developed world. Two main themes emerged from the meeting: the importance of timely detection, and the need for a tailored approach to the care of EAOCRC. Early detection is crucial, especially in light of the later stage at diagnosis and unique tumour characteristics. Symposium participants were strongly in favour of reducing the age of eligibility for screening from 50 to 45, and promoting the development of non-invasive screening techniques such as testing for circulating tumour DNA and biomarkers. Leading approaches to care were described and discussed, which meet the unique treatment needs of younger CRC patients. Multidisciplinary practices within and outside Canada address such factors as fertility, family roles, education, careers and financial responsibilities. These models can be applied in treatment centres across the country.

Optimizing management for early-stage esophageal adenocarcinoma: longitudinal results from a multidisciplinary program.

BACKGROUND: The management of early-stage esophageal cancer is nuanced. A multidisciplinary approach may optimize management through selection of candidates for surgical or endoscopic therapies. The objective of this research was to examine long-term outcomes of patients with early-stage esophageal cancer who undergo treatment with endoscopic resection or surgery. METHODS: Data on patient demographics, co-morbidities, pathology results, OS and RFS were obtained for both the endoscopic resection group and esophagectomy group. Univariate analysis of OS and RFS were conducted using the Kaplan-Meier method with calculation of the log-rank test. Multivariate cox-proportional hazards models were created for OS and RFS using a hypothesis-driven approach. A multivariate logistic regression model was created to identify predictors of esophagectomy among patients undergoing initial endoscopic resection. RESULTS: A total of 111 patients were included. The median OS for the surgery group was 67.0 months compared to 74.0 months in the endoscopic resection group (log-rank p = 0.93). The median RFS for the surgery group was 109.4 months compared to 63.3 months in the endoscopic resection group (log-rank p = 0.0127). On multivariable analysis, patients undergoing endoscopic resection had significantly worse RFS (HR 2.55, 95% CI 1.09-6.00; p = 0.032), but equivalent OS (HR 1.03, 95% CI 0.46-2.32; p = 0.941), compared to patients undergoing esophagectomy. High-grade disease (OR 5.43, 95% CI 1.13-26.10; p = 0.035) and submucosal involvement (OR 7.75, 95% CI 1.90-31.40; p = 0.004) were identified as significant predictors of proceeding to esophagectomy. CONCLUSIONS: Through a multidisciplinary approach, patients with early-stage esophageal cancer achieve excellent RFS and OS. Submucosal involvement and high-grade disease place patients at increased risk for local disease recurrence; these patients may undergo endoscopic resection safely if treated with a multidisciplinary approach incorporating endoscopic surveillance and surgical consultation. Further risk-stratification models may enable better patient selection and optimization of long-term outcomes.

Endoscopic plication compared to laparoscopic fundoplication in the treatment of gastroesophageal reflux disease: a systematic review and meta-analysis.

INTRODUCTION: Endoscopic plication offers an alternative to surgical fundoplication for treatment of gastroesophageal reflux disease (GERD). This systematic review and meta-analysis evaluate outcomes following endoscopic plication compared to laparoscopic fundoplication. METHODS AND PROCEDURES: Systematic search of MEDLINE, Embase, Scopus, and Web of Science was conducted in September 2022. Study followed PRISMA guidelines. Studies comparing endoscopic plication to laparoscopic fundoplication with n > 5 were included. Primary outcome was PPI cessation, with secondary outcomes including complications, procedure duration, length of stay, change in lower esophageal sphincter (LES) tone, and DeMeester score. RESULTS: We reviewed 1544 studies, with five included comparing 105 (46.1%) patients receiving endoscopic plication (ENDO) to 123 (53.9%) undergoing laparoscopic fundoplication (LAP). Average patient age was 47.6 years, with those undergoing plication being younger (46.4 ENDO vs 48.5 LAP). BMI (26.6 kg/m2 ENDO vs 26.2 kg/m2 LAP), and proportion of females (42.9% ENDO vs 37.4% LAP) were similar. Patients undergoing laparoscopic procedures had worse baseline LES pressure (12.8 mmHg ENDO vs 9.0 mmHg LAP) and lower preoperative DeMeester scores (34.6 ENDO vs. 34.1 LAP). The primary outcome demonstrated that 89.2% of patients undergoing laparoscopic fundoplication discontinued PPI compared to 69.4% for those receiving plication. Meta-analysis revealed that plication had significantly reduced odds of PPI discontinuation (OR 0.27, studies = 3, 95% CI 0.12 to 0.64, P = 0.003, I2 = 0%). Secondary outcomes demonstrated that odds of complications (OR 1.46, studies = 4, 95% CI 0.34 to 6.32, P = 0.62, I2 = 0%), length of stay (MD - 1.37, studies = 3, 95% CI - 3.48 to 0.73, P = 0.20, I2 = 94%), and procedure durations were similar (MD 0.78, studies = 3, 95% CI - 39.70 to 41.26, P = 0.97, I2 = 98%). CONCLUSIONS: This is the first meta-analysis comparing endoscopic plication to laparoscopic fundoplication. Results demonstrate greater likelihood of PPI discontinuation with laparoscopic fundoplication with similar post-procedural risk.

7-hydroxycoumarin-ß-D-glucuronide protects against cisplatin-induced acute kidney injury via inhibiting p38 MAPK-mediated apoptosis in mice.

AIMS: Cisplatin is a widely-used drug in the clinical treatment of tumors, but kidney nephrotoxicity is one of the reasons that limits its widespread use. We previously found that 7-hydroxycoumarin-ß-D-glucuronide (7-HCG) was one of metabolites of skimmin and highly enriched in the kidneys and maintained a high blood concentration in skimmin-treated rats. Therefore, we investigated whether 7-HCG has a protective effect on cisplatin-induced acute kidney injury. MATERIALS AND METHODS: Male C57BL/6 mice were continuously administered 7-HCG for five days, and on the third day, an intraperitoneal injection of cisplatin was given to induce acute kidney injury. After 72 h, the mice were sacrificed for analysis. Serum and renal tissue were collected for renal function evaluation. RNA sequencing was used to explore mechanism, and further validated by western blot and immunohistochemistry. In addition, pharmacokinetic study of oral 7-HCG administration was performed to examine how much 7-hydroxycoumarin (7-HC) was metabolized and 7-HC possible effect on renal protection. KEY FINDINGS: 7-HCG significantly reduced serum BUN and SCR levels, and alleviated pathological damage in renal tissue, and reduced the renal index. RNA sequencing revealed that 7-HCG could reverse p38 MAPK regulation and apoptosis. By western blotting, it was found that 7-HCG could reduce renal injury by reducing p-p38, p-ERK, p-JNK, cleaved-caspase3 and Bax. The immunohistochemical results of cleaved-caspase3 were consistent with western blotting. 7-HCG also significantly reduced the production of ROS in kidney tissue. Pharmacokinetic experiments have shown that 7-HCG in the blood increased rapidly and was eliminated slowly, with an average t1/2ß of 18.3 h. And the concentration of 7-HCG in the target organ kidney was about 4 times higher than that in blood. SIGNIFICANCE: Our findings indicate that 7-HCG could exert its protective effect against cisplatin-induced acute kidney injury by inhibiting apoptosis via p38 MAPK regulation and elucidates its pharmacokinetics.

Long-Term Patient-Reported Quality of Life of Anal Cancer Survivors Treated With Intensity Modulated Radiation Therapy and Concurrent Chemotherapy: Results From a Prospective Phase II Trial.

PURPOSE: Intensity modulated radiation therapy (IMRT) has confirmed its superiority in improving acute treatment-related toxicities in anal cancer, without compromising tumor control. However, the effect of IMRT on long-term quality of life (QOL) is poorly documented. The study prospectively evaluated the long-term patient-reported QOL after IMRT-based chemoradiation in anal cancer. METHODS AND MATERIALS: Fifty-eight patients treated with IMRT and concurrent 5 fluorouracil/mitomycin-C were enrolled in the study. A prespecified secondary endpoint was prospective evaluation of long-term QOL. Fifty-four patients underwent QOL evaluation at baseline, after treatment, and during follow-up until 60 months, with European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-C30 (EORTC QLQ-C30) scales and the Colorectal Cancer-Specific Quality Of Life Questionnaire (QLQ-CR29) scales. The QOL scores at baseline and posttreatment periods were compared. RESULTS: For QLQ-C30, at 60 months, the mean scores of global health status, all functional scales, and all symptoms except diarrhea had improved, indicating normalization of QOL. Clinically and statistically significant improvements in the global health status (15.4; P = .003), role functioning (19.3; P = .0017), emotional functioning (18.9; P = .008), and social functioning (29.8; P ≤ .001) were observed. Diarrhea persisted as a concern over the years (P = .172). For European Organization for Research and Treatment of Cancer QLQ-CR29, rectal pain (-38.6; P = .001), mucous or blood discharge per rectum (-22.8; P = .005), and perianal soreness (-37.3; P ≤ .001) were improved both clinically and statistically. Clinically significant fecal leakage was reported by 16% of patients (5.6; P = .421). Volumes receiving 45 and 54 Gy were independent predictors for fecal incontinence. Clinically and statistically significant urinary incontinence occurred in 21% of patients (17.5; P = .014). Deterioration of dyspareunia was clinically significant (26.7; P = .099) at 60 months. CONCLUSIONS: Compared with historical data, IMRT is associated with reduced long-term effects on QOL. The majority of patients treated with IMRT experienced clinically significant recovery of function and improvement in QOL over 5 years after completion of treatment. Specific toxicities such as chronic diarrhea, fecal incontinence, and urinary and sexual dysfunction were primarily responsible for deterioration of the long-term QOL. Future research aimed at reducing such toxicities is needed to further improve long-term QOL in anal cancer.

Selective photodynamic eradication of senescent cells with a ß-galactosidase-activated photosensitiser.

A ß-galactosidase-responsive photosensitiser has been designed and synthesised. It contains a galactosyl substrate, a boron dipyrromethene-based photosensitising unit and a black hole quencher 2 connected via an AB2-type self-immolative linker. This novel photosensitiser can be selectively activated by the senescence-associated ß-galactosidase in senescent cells, leading to restoration in fluorescence emission and effective killing of the cells via photodynamic action.

Improved Survival in a Cohort of Patients Aged 75 Years and Older With Fecal Immunochemical Testing-Detected Colorectal Cancer.

BACKGROUND: Fecal immunochemical testing is an accepted form of colorectal cancer screening and is recommended for adults up to the age of 75 years in Canadian guidelines. However, many individuals 75 years and older continue to receive fecal immunochemical testing despite being outside accepted guidelines. OBJECTIVE: This study aimed to determine whether patients aged 75 years and older with screen-detected cancer demonstrated improved outcomes and survival compared with patients with non-screen-detected cancer. DESIGN: This is a retrospective population-based cohort study. SETTINGS: Provincial data were collected from the Alberta Cancer Registry and the Alberta Colorectal Cancer Screening Program between November 2013 and 2019. PATIENTS: We identified an aggregated patient cohort aged 75 years and older with a diagnosis of colorectal cancer from November 2013 to November 2019, as well as patients 75 years and older who underwent fecal immunochemical testing within these dates. MAIN OUTCOME MEASURES: The proportion of screen-detected colorectal cancers was calculated. Surgical intervention, hospital length of stay, postoperative mortality, and overall survival were analyzed. RESULTS: Between November 2013 and 2019, 3586 patients 75 years and older were diagnosed with colorectal cancer; 690 (19%) were "screen-detected." Screen-detected patients were almost 3 times more likely to undergo surgery (OR, 2.83) and had a 36% overall survival benefit (HR, 0.64) compared with non-screen-detected patients, adjusted for other variables such as age, Charlson Comorbidity Index, and stage. LIMITATIONS: The retrospective study design prevents conclusions regarding causation. CONCLUSIONS: Screen detection of colorectal cancer in patients aged 75 years and older is associated with improved overall survival when controlling for other potential confounders. When compared with their non-screen-detected counterparts, these patients have an earlier stage of disease and are more likely to undergo surgical intervention with improved outcomes, irrespective of age. These data may support screening for appropriately selected patients who would otherwise fall outside of current guidelines. See Video Abstract at http://links.lww.com/DCR/B986 . SOBREVIDA MEJORADA EN UNA COHORTE DE PACIENTES DE AOS O MS CON CNCER COLORRECTAL DETECTADOS POR RIF: ANTECEDENTES:La prueba basada en una Reacción Inmunoquímica Fecal - RIF, es una forma aceptada de detección de cáncer colorrectal y esta recomendada en adultos a partir de los 75 años en las guías canadienses. Sin embargo, muchas personas de 75 años o más continúan realizándose pruebas inmunoquímicas fecales a pesar de estar fuera de las guías aceptadas.OBJETIVO:Poder determinar si los pacientes de 75 años o más con detección RIF positiva a un cáncer demuestran mejores resultados y sobrevida comparados con los pacientes sin detección.DISEÑO:Estudio de cohortes retrospectivo basado en una población definida.CONFIGURACIÓN:Se recopilaron los datos provinciales del Registro de cánceres y del Programa de detección de cáncer colorrectal de Alberta, Canada, entre 2013 y 2019.PACIENTES:Identificamos una cohorte agregada de pacientes de 75 años o más con diagnóstico de cáncer colorrectal desde noviembre de 2013 hasta noviembre de 2019, así como pacientes de 75 años o más que se sometieron a pruebas inmunoquímicas fecales dentro de las fechas mencionadas.PRINCIPALES MEDIDAS DE RESULTADO:Se calculó la proporción de cánceres colorrectales detectados mediante un cribado. Se analizaron la intervención quirúrgica, la duración de la estadía hospitalaria, la mortalidad post-operatoria y la sobrevida global.RESULTADOS:Entre noviembre de 2013 y noviembre 2019, 3586 pacientes de 75 años o más, fueron diagnosticados con cáncer colorrectal; 690 (19%) fueron detectados por cribado. Los pacientes detectados mediante el cribado, tenían casi tres veces más probabilidades de someterse a una cirugía (Razón de Probabilidad de 2,83) y beneficiaron de una sobrevida general del 36 % (HR 0,64) comparados con los pacientes sin detectación por cribado, corregidos por otras variables como la edad, el índice de comorbilidad de Charlson y el estadío del tumor.LIMITACIONES:El diseño retrospective del presente estudio impide obtener conclusiones con respecto a la causalidad.CONCLUSIONES:La detección por cribado de cáncer colorrectal en pacientes de 75 años o más se asocia con una mejor sobrevida general cuando se controlan los otros posibles factores de confusión. Comparando con las contrapartes no detectadas por cribado, estos pacientes se encuentran en una etapa más temprana de la enfermedad y es más probable que se sometan a una intervención quirúrgica con mejores resultados, independientemente a la edad. Estos datos pueden respaldar la detección de pacientes adecuadamente seleccionados que, de otro modo, quedarían fuera de las pautas actuales. Consulte Video Resumen en http://links.lww.com/DCR/B986 . (Traducción-Dr. Xavier Delgadillo ).

Toward Precise Antitumoral Photodynamic Therapy Using a Dual Receptor-Mediated Bioorthogonal Activation Approach.

Targeted delivery and specific activation of photosensitizers can greatly improve the treatment outcome of photodynamic therapy. To this end, we report herein a novel dual receptor-mediated bioorthogonal activation approach to enhance the tumor specificity of the photodynamic action. It involves the targeted delivery of a biotinylated boron dipyrromethene (BODIPY)-based photosensitizer, which is quenched in the native form by the attached 1,2,4,5-tetrazine unit, and an epidermal growth factor receptor (EGFR)-targeting cyclic peptide conjugated with a bicycle[6.1.0]non-4-yne moiety. Only for cancer cells that overexpress both the biotin receptor and EGFR, the two components can be internalized preferentially where they undergo an inverse electron-demand Diels-Alder reaction, leading to restoration of the photodynamic activity of the BODIPY core. By using a range of cell lines with different expression levels of these two receptors, we have demonstrated that this stepwise "deliver-and-click" approach can confine the photodynamic action on a specific type of cancer cells.

TRPV1 Modulator Ameliorates Alzheimer-Like Amyloid-ß Neuropathology via Akt/Gsk3ß-Mediated Nrf2 Activation in the Neuro-2a/APP Cell Model.

Alzheimer's disease (AD) is a progressive and irreversible neurodegenerative disorder for which there is no effective therapeutic strategy. PcActx peptide from the transcriptome of zoantharian Palythoa caribaeorum has recently been identified and verified as a novel antagonist of transient receptor potential cation channel subfamily V member 1 (TRPV1). In the present study, we further investigated the neuroprotective potential of PcActx peptide and its underlying mechanism of action, in an N2a/APP cell model of AD. Both Western blot and RT-PCR analysis revealed that PcActx peptide markedly inhibited the production of amyloid-related proteins and the expression of BACE1, PSEN1, and PSEN2. Moreover, PcActx peptide notably attenuated the capsaicin-stimulated calcium response and prevented the phosphorylation of CaMKII and CaMKIV (calcium-mediated proteins) in N2a/APP cells. Further investigation indicated that PcActx peptide significantly suppressed ROS generation through Nrf2 activation, followed by enhanced NQO1 and HO-1 levels. In addition, PcActx peptide remarkably improved Akt phosphorylation at Ser 473 (active) and Gsk3ß phosphorylation at Ser 9 (inactive), while pharmacological inhibition of the Akt/Gsk3ß pathway significantly attenuated PcActx-induced Nrf2 activation and amyloid downregulation. In conclusion, PcActx peptide functions as a TRPV1 modulator of intercellular calcium homeostasis, prevents AD-like amyloid neuropathology via Akt/Gsk3ß-mediated Nrf2 activation, and shows promise as an alternative therapeutic agent for AD.

The Effect of Covid-19 Pandemic on Current and Future Endoscopic Personal Protective Equipment Practices: A National Survey of 77 Endoscopists.

Introduction: The COVID-19 pandemic has raised awareness about the importance of personal protective equipment (PPE). We aimed to study and compare PPE practices among Canadian endoscopists before and after the COVID-19 pandemic. Methods: A 74-item questionnaire was emailed from June 2020 to September 2020 to practicing endoscopists in Canada. Survey questions collected basic demographics and differences between PPE practices pre- and post-COVID-19. PPE practices were categorized into four endoscopic procedure types including upper or lower endoscopy and diagnostic or interventional. Outcomes for specific procedures were reported as rates, with ranges shown when evaluating all procedure types together. Results: A total of 77 respondents completed the survey with the majority of respondents aged 40 to 49 (44%) and identifying as Gastroenterologists (70%). Gender was evenly split (49% females versus 51% males). In the pre-pandemic era, the majority of endoscopists wore gowns (91 to 94%) and all endoscopists wore gloves (100%). However, the majority of endoscopists did not wear surgical masks (21 to 31%), face shields (13 to 34%), eye protection (13 to 21%), hair protection (11 to 13%), or N95 respirators (2 to 3%). In the post-pandemic era, more surgeons plan on wearing face shields (33 to 47%, P = 0.001 to 0.045), goggles (38.5 to 58.7%, P < 0.001), hair protection (33 to 36%, P = 0.011 to 0.024), and a trend suggests more surgeons will wear surgical masks (51 to 61%, P = 0.163 to 0.333). More endoscopists also plan on wearing N95 respirators during lower endoscopy (6 to 7%, P < 0.005). Conclusion: The COVID-19 pandemic has changed the attitudes of many endoscopists regarding future PPE use in routine endoscopy. Ongoing studies are needed to inform new post-pandemic PPE consensus guidelines.

Anti-epileptic Kunitz-like peptides discovered in the branching coral Acropora digitifera through transcriptomic analysis.

Approximately 50 million people are suffering from epilepsy worldwide. Corals have been used for treating epilepsy in traditional Chinese medicine, but the mechanism of this treatment is unknown. In this study, we analyzed the transcriptome of the branching coral Acropora digitifera and obtained its Kyoto Encyclopedia of Genes and Genomes (KEGG), EuKaryotic Orthologous Groups (KOG) and Gene Ontology (GO) annotation. Combined with multiple sequence alignment and phylogenetic analysis, we discovered three polypeptides, we named them AdKuz1, AdKuz2 and AdKuz3, from A. digitifera that showed a close relationship to Kunitz-type peptides. Molecular docking and molecular dynamics simulation indicated that AdKuz1 to 3 could interact with GABAA receptor but AdKuz2-GABAA remained more stable than others. The biological experiments showed that AdKuz1 and AdKuz2 exhibited an anti-inflammatory effect by decreasing the aberrant level of nitric oxide (NO), IL-6, TNF-α and IL-1ß induced by LPS in BV-2 cells. In addition, the pentylenetetrazol (PTZ)-induced epileptic effect on zebrafish was remarkably suppressed by AdKuz1 and AdKuz2. AdKuz2 particularly showed superior anti-epileptic effects compared to the other two peptides. Furthermore, AdKuz2 significantly decreased the expression of c-fos and npas4a, which were up-regulated by PTZ treatment. In addition, AdKuz2 reduced the synthesis of glutamate and enhanced the biosynthesis of gamma-aminobutyric acid (GABA). In conclusion, the results indicated that AdKuz2 may affect the synthesis of glutamate and GABA and enhance the activity of the GABAA receptor to inhibit the symptoms of epilepsy. We believe, AdKuz2 could be a promising anti-epileptic agent and its mechanism of action should be further investigated.

Early-Age-Onset Colorectal Cancer in Canada: Evidence, Issues and Calls to Action.

The inaugural Early-Age-Onset Colorectal Cancer Symposium was convened in June 2021 to discuss the implications of rapidly rising rates of early-age-onset colorectal cancer (EAO-CRC) in Canadians under the age of 50 and the impactful outcomes associated with this disease. While the incidence of CRC is declining in people over the age of 50 in Canada and other developed countries worldwide, it is significantly rising in younger people. Canadians born after 1980 are 2 to 2.5 times more likely to be diagnosed with CRC before the age of 50 than previous generations at the same age. While the etiology of EAO-CRC is largely unknown, its characteristics differ in many key ways from CRC diagnosed in older people and warrant a specific approach to risk factor identification, early detection and treatment. Participants of the symposium offered directions for research and clinical practice, and developed actionable recommendations to address the unique needs of these individuals diagnosed with EAO-CRC. Calls for action emerging from the symposium included: increased awareness of EAO-CRC among public and primary care practitioners; promotion of early detection programs in younger populations; and the continuation of research to identify unique risk factor profiles, tumour characteristics and treatment models that can inform tailored approaches to the management of EAO-CRC.

Specific Activation of Photosensitizer with Extrinsic Enzyme for Precisive Photodynamic Therapy.

Delivery of functional proteins into the intracellular space has been a challenging task that could lead to a myriad of therapeutic applications. We report herein a novel bioconjugation strategy for enzyme modification and selective delivery into cancer cells for lock-and-key-type activation of photosensitizers. Using a bifunctional linker containing a bis(bromomethyl)phenyl group and an o-phthalaldehyde moiety, it could induce cyclization of the peptide sequence Ac-NH-CRGDfC-CONH2 through site-specific dibenzylation with the two cysteine residues and further coupling with ß-galactosidase via the phthalaldehyde-amine capture reaction. This facile two-step one-pot procedure enabled the preparation of cyclic RGD-modified ß-galactosidase readily, which could be internalized selectively into αvß3 integrin-overexpressed cancer cells. Upon encountering an intrinsically quenched distyryl boron dipyrromethene-based photosensitizer conjugated with a galactose moiety through a self-immolative linker inside the cells, the extrinsic enzyme induced specific cleavage of the ß-galactosidic bond followed by self-immolation to release an activated derivative, thereby restoring the photodynamic activities and causing cell death effectively. The high specificity of this extrinsic enzyme-activated photosensitizing system was also demonstrated in vivo using nude mice bearing an αvß3 integrin-positive U87-MG tumor. The specific activation at the tumor site resulted in lighting up and complete eradication of the tumor upon laser irradiation, while by using the native ß-galactosidase, the effects were largely reduced. In contrast to the conventional activation using intrinsic enzymes, this extrinsic enzyme activatable approach can further minimize the nonspecific activation toward precisive photodynamic therapy.