Risk-stratification for treatment de-intensification in WNT-pathway medulloblastoma: finding the optimal balance between survival and quality of survivorship.

INTRODUCTION: Advances in molecular biology have led to consensus classification of medulloblastoma into four broad molecular subgroups - wingless (WNT), sonic hedgehog (SHH), Group 3, and Group 4 respectively. Traditionally, children > 3-years of age, with no/minimal residual tumor (<1.5 cm2) and lack of metastasis were classified as average-risk disease with > 80% long-term survival. Younger age (<3 years), large residual disease (≥1.5 cm2), and leptomeningeal metastases either alone or in combination were considered high-risk features yielding much worse 5-year survival (30-60%). This clinico-radiological risk-stratification has been refined by incorporating molecular/genetic information. Contemporary multi-modality management for non-infantile medulloblastoma entails maximal safe resection followed by risk-stratified adjuvant radio(chemo)therapy. Aggressive multi-modality management achieves good survival but is associated with substantial dose-dependent treatment-related toxicity prompting conduct of subgroup-specific prospective clinical trials. AREAS COVERED: We conducted literature search on PubMed from 1969 till 2023 to identify putative prognostic factors and risk-stratification for medulloblastoma including molecular subgrouping. Based on previously published data including our own institutional experience, we discuss molecular risk-stratification focusing on WNT-pathway medulloblastoma to identify candidates suitable for treatment de-intensification to strike the optimal balance between survival and quality of survivorship. EXPERT OPINION: Prospective clinical trials and emerging biological information should further refine risk-stratification in WNT-pathway medulloblastoma.

PRRT with Lu-177 DOTATATE in Treatment-Refractory Progressive Meningioma: Initial Experience from a Tertiary-Care Neuro-Oncology Center.

PURPOSE: Refractory and/or recurrent meningiomas have poor outcomes, and the treatment options are limited. Peptide receptor radionuclide therapy (PRRT) has been used in this setting with promising results. We have documented our experience of using intravenous (IV) and intra-arterial (IA) approaches of Lu-177 DOTATATE PRRT. METHODS: Eight patients with relapsed/refractory high-grade meningioma received PRRT with Lu-177 DOTATATE by IV and an IA route. At least 2 cycles were administered. Time to progression was calculated from the first PRRT session to progression. The response was assessed on MRI using RANO criteria, and visual analysis of uptake was done on Ga-68 DOTANOC PET/CT. Post-therapy dosimetry calculations for estimating the absorbed dose were performed. RESULTS: Median time to progression was 8.9 months. One patient showed disease progression, whereas seven patients showed stable disease at 4 weeks following 2 cycles of PRRT. Dosimetric analysis showed higher dose and retention time by IA approach. No significant peri-procedural or PRRT associated toxicity was seen. CONCLUSION: PRRT is a safe and effective therapeutic option for relapsed/refractory meningioma. The IA approach yields better dose delivery and should be routinely practised.

Pheromone-mediated command from the female to male clock induces and synchronizes circadian rhythms of the moth Spodoptera littoralis.

To extract any adaptive benefit, the circadian clock needs to be synchronized to the 24-h day-night cycles. We have investigated if it is a general property of the brain's circadian clock to recognize social interactions as external time givers. Sociosexual interactions with the opposite sex are universal, prevalent even in the lives of solitary animals. The solitary adult life of the Spodoptera littoralis moth is singularly dedicated to sex, offering an ideal context for exploring the impact of sociosexual cues on circadian timekeeping. We have identified specific olfactory cues responsible for social entrainment, revealing a surprisingly strong influence of pheromone-mediated remote sociosexual interactions on circadian rhythms. Males' free-running rhythms are induced and synchronized by the sex pheromone that the female releases in a rhythmic fashion, highlighting a hierarchical relation between the female and male circadian oscillators. Even a single pulse of the sex pheromone altered clock gene expression in the male brain, surpassing the effect of light on the clock. Our finding of a daytime-dependent, lasting impact of pheromone on male's courtship efficacy indicates that circadian timing in moths is a trait under sexual selection. We have identified specific components of the sex-pheromone blend that lack mate-attractive property but have powerful circadian effects, providing rationale for their continued retention by the female. We show that such volatiles, when shared across sympatric moth species, can trigger communal synchronization. Our results suggest that the sex pheromone released by female moths entrains males' behavioral activity rhythm to ensure synchronized timing of mating.

A Genetically Encoded Photocaged Cysteine for Facile Site-Specific Introduction of Conjugation-Ready Thiol Residues in Antibodies.

Antibody-drug conjugates (ADCs) have emerged as a powerful class of anticancer therapeutics that enable the selective delivery of toxic payloads into target cells. There is increasing appreciation for the importance of synthesizing such ADCs in a defined manner where the payload is attached at specific permissive sites on the antibody with a defined drug to antibody ratio. Additionally, the ability to systematically alter the site of attachment is important to fine-tune the therapeutic properties of the ADC. Engineered cysteine residues have been used to achieve such site-specific programmable attachment of drug molecules onto antibodies. However, engineered cysteine residues on antibodies often get "disulfide-capped" during secretion and require reductive regeneration prior to conjugation. This reductive step also reduces structurally important disulfide bonds in the antibody itself, which must be regenerated through oxidation. This multistep, cumbersome process reduces the efficiency of conjugation and presents logistical challenges. Additionally, certain engineered cysteine sites are resistant to reductive regeneration, limiting their utility and the overall scope of this conjugation strategy. In this work, we utilize a genetically encoded photocaged cysteine residue that can be site-specifically installed into the antibody. This photocaged amino acid can be efficiently decaged using light, revealing a free cysteine residue available for conjugation without disrupting the antibody structure. We show that this ncAA can be incorporated at several positions within full-length recombinant trastuzumab and decaged efficiently. We further used this method to generate a functional ADC site-specifically modified with monomethyl auristatin F (MMAF).

Melatonin Inhibits AGS Cell Proliferation by Binding to the ATP Binding Site of CDK2 Under Hyperglycemic Conditions.

Cancer cells utilize glucose as their primary energy source. The aggressive nature of cancer cells is therefore enhanced in hyperglycemic conditions. This study has been adopted to investigate the therapeutic potential of melatonin against such aggressive proliferation of AGS cells-a human gastric cancer cell line, under hyperglycemic conditions. AGS cells were incubated with high glucose-containing media, and the effects of melatonin have been evaluated, therein. Cell proliferation, ROS generation, flow-cytometric analysis for cell cycle and apoptosis, wound healing, immunoblotting, zymography, reverse zymography assays, in-silico analysis, and kinase activity assays were performed to evaluate the effects of melatonin. We observed that melatonin inhibited the hyperglycemia-induced cell proliferation in a dose-dependent manner. It further altered the expression and activity of MMP-9 and TIMP-1. Moreover, melatonin inhibited AGS cell proliferation by arresting AGS cells in the G0/G1 phase after binding in the ATP binding site of CDK-2, thereby inhibiting its kinase activity. In association, a significant decrease in the expression of cyclin D1, cyclin E, CDK-4, and CDK-2 were observed. In conclusion, these findings suggest that melatonin has anti-gastric cancer potential. Melatonin could therefore be included in future drug designs for gastric cancer-hyperglycemia co-morbidity treatment.

Relevance of sleep for wellness: New trends in using artificial intelligence and machine learning.

Sleep and well-being have been intricately linked, and sleep hygiene is paramount for developing mental well-being and resilience. Although widespread, sleep disorders require elaborate polysomnography laboratory and patient-stay with sleep in unfamiliar environments. Current technologies have allowed various devices to diagnose sleep disorders at home. However, these devices are in various validation stages, with many already receiving approvals from competent authorities. This has captured vast patient-related physiologic data for advanced analytics using artificial intelligence through machine and deep learning applications. This is expected to be integrated with patients' Electronic Health Records and provide individualized prescriptive therapy for sleep disorders in the future.

Existing and Evolving Landscape of Medulloblastoma: Towards Optimization and Personalization.

Advances in diagnostic imaging, pathology, and molecular biology coupled with improvements in neurosurgical approaches, radiotherapeutic techniques, and systemic therapies over the last two decades have vastly improved survival outcomes for medulloblastoma, the most common childhood malignant tumor [...].

MicroRNA-409-3p/BTG2 signaling axis improves impaired angiogenesis and wound healing in obese mice.

Wound healing is facilitated by neoangiogenesis, a complex process that is essential to tissue repair in response to injury. MicroRNAs are small, noncoding RNAs that can regulate the wound healing process including stimulation of impaired angiogenesis that is associated with type-2 diabetes (T2D). Expression of miR-409-3p was significantly increased in the nonhealing skin wounds of patients with T2D compared to the non-wounded normal skin, and in the skin of a murine model with T2D. In response to high glucose, neutralization of miR-409-3p markedly improved EC growth and migration in human umbilical vein endothelial cells (HUVECs), promoted wound closure and angiogenesis as measured by increased CD31 in human skin organoids, while overexpression attenuated EC angiogenic responses. Bulk mRNA-Seq transcriptomic profiling revealed BTG2 as a target of miR-409-3p, where overexpression of miR-409-3p significantly decreased BTG2 mRNA and protein expression. A 3' untranslated region (3'-UTR) luciferase assay of BTG2 revealed decreased luciferase activity with overexpression of miR-409-3p, while inhibition had opposite effects. Mechanistically, in response to high glucose, miR-409-3p deficiency in ECs resulted in increased mTOR phosphorylation, meanwhile BTG-anti-proliferation factor 2 (BTG2) silencing significantly decreased mTOR phosphorylation. Endothelial-specific and tamoxifen-inducible miR-409-3p knockout mice (MiR-409IndECKO ) with hyperglycemia that underwent dorsal skin wounding showed significant improvement of wound closure, increased blood flow, granulation tissue thickness (GTT), and CD31 that correlated with increased BTG2 expression. Taken together, our results show that miR-409-3p is a critical mediator of impaired angiogenesis in diabetic skin wound healing.

The Keystone Perforator Island Flap: Review of Utility and Versatile Clinical Applications.

Background: The keystone perforator island flap (KPIF) was described almost a decade ago. However, this flap has only recently been recognized for its advantages in various clinical applications in plastic surgery. A better understanding of the versatility of KPIFs can help promote the widespread adoption of this technique for complex wounds in various anatomical regions. Methods: A retrospective chart review was conducted of patients undergoing KPIFs from December 2018 to March 2022 at the authors' home institution. The indications, surgical approaches, patient characteristics, and outcomes were extracted for review and analysis. Results: A total of 12 patients (ages 13-86 years) underwent reconstruction with KPIFs for oncologic and nononcologic defects. By anatomic region, three cases involved the upper back, six involved the lumbosacral region, one involved the perineum, and two involved the midfoot. Half of the patients (n = 6) had failed previous attempts at wound closure. The mean defect size was 13.8 × 10.0 cm for the upper back lesions, 13.7 × 4.8 for the lumbosacral defects, and 3.5 × 2.0 for the metatarsal wounds. Median follow-up time for all patients was 7.5 months (IQR: 4-10.5). On follow-up, there was 100% flap survival. Conclusion: KPIFs are a simple, safe, and suitable option for reconstructive closure of defects in many anatomical areas, including wounds complicated by previous failed closure attempts, with low complication risk profile.

Unusual Presentation of Reversible Transient Vision Loss After Caesarean Section Under Subarachnoid Block: A Case Report.

A transient vision loss is not commonly encountered during the postoperative period following a caesarean section. Although numerous causes have been suggested for transient vision loss, when loss of vision is associated with seizures and headaches, the differential diagnoses include hemolysis, elevated liver enzymes, low platelet syndrome, reversible cerebral vasoconstriction syndrome, posterior reversible encephalopathy syndrome (PRES), dural venous thrombosis, and central retinal arteriolar occlusion. We report a case of a 35-year-old patient who underwent an elective caesarean section under spinal anaesthesia and developed a headache followed by loss of vision and seizures during the postoperative period. An MRI scan of the brain on the same day revealed subtle hyperintensity in bilateral parieto-occipital lobes in the cortical and subcortical areas and bilateral cerebral hemispheres, which indicates PRES. Rapid and complete resolution of symptoms was observed with supportive treatment. Therefore, prompt suspicion and effective management of PRES are of paramount importance to prevent short- and long-term neurological deficits.

Clinico-Radiological Outcomes in WNT-Subgroup Medulloblastoma.

Medulloblastoma (MB) comprises four broad molecular subgroups, namely wingless (WNT), sonic hedgehog (SHH), Group 3, and Group 4, respectively, with subgroup-specific developmental origins, unique genetic profiles, distinct clinico-demographic characteristics, and diverse clinical outcomes. This is a retrospective audit of clinical outcomes in molecularly confirmed WNT-MB patients treated with maximal safe resection followed by postoperative standard-of-care risk-stratified adjuvant radio(chemo)therapy at a tertiary-care comprehensive cancer centre. Of the 74 WNT-MB patients registered in a neuro-oncology unit between 2004 to 2020, 7 patients accrued on a prospective clinical trial of treatment deintensification were excluded, leaving 67 patients that constitute the present study cohort. The median age at presentation was 12 years, with a male preponderance (2:1). The survival analysis was restricted to 61 patients and excluded 6 patients (1 postoperative mortality plus 5 without adequate details of treatment or outcomes). At a median follow-up of 72 months, Kaplan-Meier estimates of 5-year progression-free survival and overall survival were 87.7% and 91.2%, respectively. Traditional high-risk features, large residual tumour (≥1.5 cm2), and leptomeningeal metastases (M+) did not significantly impact upon survival in this molecularly characterized WNT-MB cohort treated with risk-stratified contemporary multimodality therapy. The lack of a prognostic impact of conventional high-risk features suggests the need for refined risk stratification and potential deintensification of therapy.

Enhanced Directed Evolution in Mammalian Cells Yields a Hyperefficient Pyrrolysyl tRNA for Noncanonical Amino Acid Mutagenesis.

Heterologous tRNAs used for noncanonical amino acid (ncAA) mutagenesis in mammalian cells typically show poor activity. We recently introduced a virus-assisted directed evolution strategy (VADER) that can enrich improved tRNA mutants from naïve libraries in mammalian cells. However, VADER was limited to processing only a few thousand mutants; the inability to screen a larger sequence space precluded the identification of highly active variants with distal synergistic mutations. Here, we report VADER2.0, which can process significantly larger mutant libraries. It also employs a novel library design, which maintains base-pairing between distant residues in the stem regions, allowing us to pack a higher density of functional mutants within a fixed sequence space. VADER2.0 enabled simultaneous engineering of the entire acceptor stem of M. mazei pyrrolysyl tRNA (tRNAPyl ), leading to a remarkably improved variant, which facilitates more efficient incorporation of a wider range of ncAAs, and enables facile development of viral vectors and stable cell-lines for ncAA mutagenesis.

CDKN2A/B deletion in IDH-mutant astrocytomas: An evaluation by Fluorescence in-situ hybridization.

INTRODUCTION: CDKN2A/B homozygous deletion is one of the defining features of grade 4 in IDH-mutant astrocytic tumours. AIM: To evaluate CDKN2A/B-deletion in IDH-mutant astrocytic tumours and its clinicopathological impact. MATERIALS AND METHODS: CDKN2A/B-deletion was evaluated by Fluorescence in-situ hybridisation (FISH) and interpreted by two recently accepted methods. RESULTS: Eighty-three out of 94 cases (histologically-grade 2: 3, grade 3: 46, grade 4: 34) were interpretable on FISH. Concordant CDKN2A/B-deletion was observed in 71% (27/38) of lower-grade tumours (n = 49) and 90% (27/30) of histological grade 4 tumours (n = 34). Both the interpretation methods showed good agreement (Kappa = 0.75). CDKN2A/B-deletion showed an inverse correlation for < 10% MIB-1 labeling index (p = 0.01) while that by method-2 showed a significant correlation for grade 4 (p = 0.02). No significant correlation was observed for any other clinicopathological parameters. Twenty-four patients showed progression/recurrence (including deaths), and no significant difference in frequency of CDKN2A/B deletion was observed among cases with disease progression across different histological grades. CONCLUSIONS: CDKN2A/B-deletion was observed across all the histological grades of IDH-mutant astrocytic tumours, expectedly more in the higher grade. FISH, as a method, can be used for the detection of CDKN2A/B homozygous deletion, when there is concordant interpretation.

Prepectoral and Retropectoral Breast-implant-Associated Anaplastic Large-cell Lymphoma.

Breast-implant-associated anaplastic large cell lymphoma (BIA-ALCL) is a non-Hodgkin lymphoma that arises in the space between the surface of a breast implant and the fibrous capsule that grows around the implant. Since its first description 20 years ago, almost 1000 cases of BIA-ALCL have been diagnosed worldwide. Nowadays, guidelines describe the diagnosis, staging, and treatment of this disease. We present the first two cases diagnosed and treated in Peru, demonstrating a wide range of aggressiveness of BIA-ALCL.

Electrochemical labelling of hydroxyindoles with chemoselectivity for site-specific protein bioconjugation.

Electrochemistry has recently emerged as a powerful approach in small-molecule synthesis owing to its numerous attractive features, including precise control over the fundamental reaction parameters, mild reaction conditions and innate scalability. Even though these advantages also make it an attractive strategy for chemoselective modification of complex biomolecules such as proteins, such applications remain poorly developed. Here we report an electrochemically promoted coupling reaction between 5-hydroxytryptophan (5HTP) and simple aromatic amines-electrochemical labelling of hydroxyindoles with chemoselectivity (eCLIC)-that enables site-specific labelling of full-length proteins under mild conditions. Using genetic code expansion technology, the 5HTP residue can be incorporated into predefined sites of a recombinant protein expressed in either prokaryotic or eukaryotic hosts for subsequent eCLIC labelling. We used the eCLIC reaction to site-specifically label various recombinant proteins, including a full-length human antibody. Furthermore, we show that eCLIC is compatible with strain-promoted alkyne-azide and alkene-tetrazine click reactions, enabling site-specific modification of proteins at two different sites with distinct labels.

Discrepancies in Financial Conflicts of Interest in Robotic Cardiothoracic Surgery Studies.

BACKGROUND: In academic surgery publications, self-reporting of conflicts of interest (COI) has often proved to be inaccurate. Here, we review the accuracy of COI disclosures for studies related to the use of robotic technology in cardiothoracic surgery and evaluate factors associated with increased discrepancies. METHODS: A literature search identified robotic surgery-related studies with at least 1 American author published between January 2015 and December 2020 from 3 major American cardiothoracic surgery journals (The Journal of Thoracic and Cardiovascular Surgery, The Annals of Thoracic Surgery, and Annals of Cardiothoracic Surgery). Industry payments from Intuitive Surgical (Intuitive) were collected with use of the Centers for Medicare and Medicaid Open Payments database. COI discrepancies were identified by comparing author declaration statements with payments found for the year of publication and the year prior (24-month period). RESULTS: A total of 144 studies (764 authors) were identified. At least 1 author of 112 studies (78%) had received payments from Intuitive. At least 1 author of 98 studies (68%) had received an undeclared payment from Intuitive. Authors who accurately disclosed payments received significantly higher median payments compared with authors who did not ($16,511 [interquartile range, $6389-$159,035] vs $1762 [interquartile range, $338-$7500]; P < .0001). Last authors were significantly more likely to have a COI discrepancy compared with middle and first authors (P = .018; P = .0015). CONCLUSIONS: Most studies investigating the use of robotic technology in cardiothoracic surgery did not accurately declare COI with Intuitive. This study highlights the need for improved accuracy of reporting industry sponsorship by publishing authors.

Patterns of Care in Craniopharyngioma: Clinical Outcomes After Surgery and Radiation Therapy in a Real-World Setting.

OBJECTIVE: Craniopharyngioma (CP) is a benign neuroepithelial tumor generally treated with maximal safe resection and radiation therapy (RT) in incompletely resected CP or in recurrent tumors to achieve long-term control. We analyzed the clinical outcomes of patients with CPs treated with a multimodality approach. PATIENTS AND METHODS: A retrospective clinical audit of histologically proven CPs registered between 2008 and 2019 at a specialized neuro-oncology center in India was performed. Time-to-event outcomes (overall survival [OS] and progression-free survival [PFS]) were analyzed. RESULTS: One hundred and twenty-two patients with CP were analyzed. The median age of the population was 14 years (interquartile range [IQR], 8-26) with a significant male preponderance. Gross total resection was achieved in only 25% of patients. At a median follow-up of 57.1 months (IQR, 27.8-87.8), 5-year estimates of PFS and OS were 52% (95% confidence interval, 46%-63.4%) and 85.8% (95% confidence interval, 78.6%-93%), respectively. Recurrence or progression was observed in 48 of 122 patients (39.3%) at a median time of 84.4 months (IQR, 24.7-174.8). On multivariate analysis, the absence of residual disease (P = 0.004), near-total resection (P = 0.035), and use of up-front adjuvant RT (P < 0.001) significantly improved the 5-year PFS, whereas the absence of extracavernous extension (P = 0.058) and any use of postoperative RT (P = 0.026) significantly improved the 5-year OS. CONCLUSIONS: This study represents one of the largest single-institutional series of CPs, showing improved PFS with up-front adjuvant RT in most cases of CP. Deferring adjuvant RT should be considered only in patients with no evidence of residual disease (as shown on dedicated sellar imaging) after primary surgery.

The Benefit of Cost-Transparency Calculators Does Not Extend to Vascular Surgery Patients.

BACKGROUND: In 2021, the Centers for Medicare & Medicaid Services (CMS) mandated that every hospital create a publicly available webtool for pricing various medical services in an effort to give patients transparency in regard to their health care expenses and allow patients to "shop around" to receive the care most fitting their budget. Our objective is to investigate the utility this mandate provides for vascular surgery patients. METHODS: Standardized searches were performed to find patient cost calculators for Newsweek's Top 50 Hospitals in the United States. If the webtool was found, a list of standardized searches were performed to investigate whether the tool listed prices for the following vascular procedures: Arteriovenous fistula (AVF), varicose vein procedures, and Endovascular Aneurysm Repair (EVAR). RESULTS: Of the 50 hospitals included, all had an easily accessible web-based cost estimator tool. The average time to find the cost estimator was 33.27 sec. Of these 50 hospitals, 10% provided cost information on AVF surgery, 12% provided cost information on varicose vein procedures, and 0% provided information on EVAR. There was no difference in the hospital's likelihood to report a price based on region of the United States. Average preinsurance price for AVF surgery was $11,933.61 and $22,191 for vein procedures. CONCLUSIONS: In conclusion, despite good adherence to the CMS mandate requiring a publicly available pricing tool, these tools provide little to no information for vascular surgery patients. Overall, this discrepancy places vascular surgery patients at a significant disadvantage. As such, vascular patients do not have access to the knowledge necessary to financially prepare for surgery, and furthermore, they are not afforded the luxury to choose where to have procedures performed based on price variability. Hopefully this research will encourage hospitals to broaden the scope of their cost calculators to allow it to benefit all patients.