Exploration of Immune-Modulatory Effects of Amivantamab in Combination with Pembrolizumab in Lung and Head and Neck Squamous Cell Carcinoma.

Immune checkpoint inhibitors are effective first-line therapy for solid cancers. However, low response rate and acquired resistance over time has led to the need for additional therapeutic options. Here, we evaluated synergistic antitumor efficacy of EGFR × MET targeting bispecific antibody, amivantamab with PD-L1 immunotherapy, pembrolizumab in head and neck squamous cell carcinoma (HNSCC) and lung squamous cell carcinoma tumor-bearing humanized patient-derived xenograft (PDX) models. We demonstrated that pembrolizumab or amivantamab alone was ineffective and that combination treatment induced a significant reduction of tumor growth in both models (P < 0.0001 and P < 0.01, respectively). It appeared that combination of amivantamab and pembrolizumab significantly enhanced infiltration of granzyme B-producing CD8 T cells was in the TME of HNSCC PDX (P < 0.01) and enhanced neoantigen-associated central memory CD8 T cells in circulating immune cells. Analysis of single-cell RNA transcriptomics suggested that the tumor cells dramatically upregulated EGFR and MET in response to PD-L1 immunotherapy, potentially creating a metabolic state fit for tumor persistence in the tumor microenvironment (TME) and rendered pembrolizumab ineffective. We demonstrated that EGFRHIGHMETHIGH subcluster displayed an increased expression of genes implicated in production of lactate [SLC16A3 and lactate dehydrogenase A (LDHA)] compared to the EGFRLOWMETLOW cluster. Accumulation of lactate in the TME has been associated with immunosuppression by hindering the infiltration of tumor killing CD8 T and NK cells. This study proved that amivantamab reduced glycolytic markers in the EGFRHIGHMETHIGH subcluster including SLC16A3 and LDHA and highlighted remodeling of the TME by combination treatment, providing rationale for additional therapy of amivantamab with PD-1 immunotherapy. SIGNIFICANCE: Amivantamab in synergy with pembrolizumab effectively eradicated EGFRHIGHMETHIGH tumor subcluster in the tumor microenvironment of head and neck squamous cell carcinoma and overcame resistance against anti-PD-1 immunotherapy.

Manifestations of radiation toxicity in the head, neck, and spine: An image-based review.

BACKGROUND AND PURPOSE: Radiation therapy is an important component of treatment in patients with malignancies of the head, neck, and spine. However, radiation to these regions has well-known potential side effects, many of which can be encountered on imaging. In this manuscript, we review selected radiographic manifestations of therapeutic radiation to the head, neck, and spine that may be encountered in the practice of radiology. METHODS: We conducted an extensive literature review of known complications of radiation therapy in the head, neck, and spine. We excluded intracranial and pulmonary radiation effects from our search. We selected complications that had salient, recognizable imaging findings. We searched our imaging database for illustrative examples of these complications. RESULTS: Based on our initial literature search and imaging database review, we selected cases of radiation-induced tumors, radiation tissue necrosis (osteoradionecrosis and soft tissue necrosis), carotid stenosis and blowout secondary to radiation, enlarging thyroglossal duct cysts, radiation myelopathy, and radiation-induced vertebral compression fractures. CONCLUSIONS: We describe the clinical and imaging features of selected sequelae of radiation therapy to the head, neck, and spine, with a focus on those with characteristic imaging findings that can be instrumental in helping to make the diagnosis. Knowledge of these entities and their imaging findings is crucial for accurate diagnosis. Not only do radiologists play a key role in early detection of these entities, but many of these entities can be misinterpreted if one is not familiar with them.

Morphological changes associated with Nile crocodile (Crocodylus niloticus) phallic glans inflation.

The crocodylian phallic glans is the distal inflatable structure that makes the most direct contact with the female cloacal and associated reproductive tract openings during copulation. Therefore, its form and function directly impact female tissue sensory interactions and insemination mechanics. Compared to mammals, less is known about glans functional anatomy among other amniotes, including crocodylians. Therefore, we paired an ex vivo inflation technique with magnetic resonance imaging 3D-reconstructions and corresponding histological analyses to better characterize the morphological glans restructuring occurring in the Nile crocodile (Crocodylus niloticus) at copulation. The expansion of contiguous inflatable spongiform glans tissues is variably constrained by adjacent regions of dense irregular collagen-rich tissues. Therefore, expansion shows regional differences with greater lateral inflation than dorsal and ventral. Furthermore, this enlargement elaborates the cup-like glans lumen, dorsally reorients the glans ridge, stiffens the blunt and bifid glans tip, and putatively works to seal the ventral sulcus spermaticus semen conduit groove. We suggest how these dynamic male structures may interact with structures of the female cloacal urodeum and how these morphological changes, in concert with the varying material properties of the structural tissue compartments visualized in this study, aid copulatory gamete transfer and resulting fecundity. RESEARCH HIGHLIGHTS: Nile crocodile glans inflation produces a reproductively relevant copulatory structure directing insemination and female tissue interactions. Pairing magnetic resonance imaging 3D reconstruction with corresponding histology effectively studies functional anatomy.

Polyclonal lymphocytic infiltrate with arachnoiditis resulting from intrathecal stem cell transplantation.

Stem cell treatment outside of studied and approved medical indications can have unforeseen adverse consequences. Here, we present a 74-year-old male that underwent such therapy. The patient presented to our institution with progressive lower extremity weakness and urinary incontinence. He had previously undergone intrathecal stem cell therapy in Moscow, Russia for weakness and fatigue. Magnetic resonance imaging of his thoracic and lumbar spine showed marked enlargement of the cauda equina nerve roots and abnormal mass-like soft tissue involving the thoracolumbar thecal sac. Surgical biopsy of the intrathecal soft tissue showed polyclonal lymphocytic and glial cell proliferation. The patient's symptoms did not improve with medical treatment or radiation, and he is currently under observation after multidisciplinary evaluation. Our patient's experience illustrates one of the potential risks of "stem cell tourism" and exemplifies the imaging and histopathologic features of this rare entity. We also compare our patient's treatment with other similar examples of stem cell treatments in our institution and others. These have had a wide spectrum of results. In some instances, intrathecal stem cells have caused abnormal imaging findings without any associated patient symptoms. In extreme examples, however, stem cell treatments have resulted in central nervous system neoplasms. Our patient's lesion is quite unique, with only one similar lesion having been previously published.

Blood pressure management and progression of chronic kidney disease in a canine remnant kidney model.

The canine remnant kidney model is fundamental to understanding the relationship between hypertension and chronic kidney disease (CKD). This study aimed to create a 1/16 remnant kidney model and to determine whether blood pressure (BP) control affects the progression of CKD. A group of dogs received BP treatment (group A) and another received BP treatment except for the first 2 weeks (group B). The remnant kidney model was induced using a two-step subtotal nephrectomy method; dogs received antihypertensive therapy. Systolic BP, blood urea nitrogen, serum creatinine, urinary protein, and creatinine levels were measured weekly. Kidney tissues were obtained at the conclusion of the study. Systolic BP was controlled to <160 mmHg in both groups for 18 weeks, except for the first 2 weeks in group B. Proteinuria was elevated after renal ligation in both groups, but gradually increased in group B and decreased in group A (p = 0.009). Blood urea nitrogen (p = 0.014) and creatinine (p = 0.020) levels were higher in group B than in group A. More histological damage was observed in group B than in group A. Induction of 1/16 nephrectomy successfully established CKD. Control of BP may be important to prevent or control the progression of CKD in dogs.

Circulating TNF receptors predict cardiovascular disease in patients with chronic kidney disease.

Cardiovascular disease (CVD) is the main public health problem in patients with chronic kidney disease (CKD); however, there is no established biomarker for predicting CVD morbidity and mortality in CKD. The aim of this study was to evaluate the role of circulating tumor necrosis factor receptors (cTNFRs) in predicting CVD risk in CKD patients.We prospectively recruited 984 patients with CKD from 11 centers between 2006 and 2012. The levels of cTNFR1 and cTNFR2 were determined by performing an enzyme-linked immunosorbent assay. During the mean follow-up period of 4 years, 36 patients experienced a CVD event. The median serum concentrations of cTNFR1 and cTNFR2 were 2703.4 (225.6-13,057.7) and 5661.0 (634.9-30,599.6) pg/mL, respectively, and the cTNFR1 level was closely correlated with the cTNFR2 level (r = 0.86, P < .0001). The urinary protein-to-creatinine ratio (UPCR) and estimated glomerular filtration rate (eGFR) were significantly correlated with the cTNFR2 level (r = 0.21 for UPCR, r = -0.67 for eGFR; P < .001 for all). Similar correlations were observed for serum cTNFR1 (r = 0.21 for UPCR, r = -0.75 for eGFR; P < .001 for all). In the Cox proportional hazard analyses, cTNFR1 (hazard ratio [HR] 2.506, 95% confidence interval [CI] 1.186-5.295, P = .016) and cTNFR2 (HR 4.156, 95% CI 1.913-9.030, P < .001) predicted CVD risk even after adjustment for clinical covariates, such as UPCR, eGFR, and high-sensitivity C-reactive protein. cTNFR1 and 2 are associated with CVD and other risk factors in CKD, independently of eGFR and UPCR. Furthermore, cTNFRs could be relevant predictors of CVD in CKD patients.

Changes in site of obstruction in obstructive sleep apnea patients according to sleep position: a DISE study.

OBJECTIVES/HYPOTHESIS: This study aimed to evaluate changes in obstruction site in obstructive sleep apnea (OSA) patients according to sleep position. STUDY DESIGN: Prospective case series. METHODS: Eighty-five patients who had undergone level 1 sleep study and drug-induced sleep endoscopy in the supine and lateral positions were included. Obstruction sites were classified as soft palate (SP), tongue base (TB), lateral wall (LW), and larynx (LX). Subgroup analysis was performed according to lateral apnea-hypopnea index (AHI): those with an AHI of ≥ 10 (lateral obstructors, LO) and those with an AHI of < 10 (lateral nonobstructors, LNO). RESULTS: Prevalence in obstruction site of SP, TB, and LX decreased significantly after change from supine to lateral position (P < 0.05). However, the prevalence of LW obstruction was not affected by position change. LW collapse in moderate OSA decreased (from 66.7% to 35.9%) after change to lateral sleep, whereas it persisted in severe OSA patients (81.6%-89.5%). In the lateral position, persistent obstruction at the LW was observed more frequently in the LO group compared to the LNO group (83.3% vs. 33.3%). CONCLUSION: When sleep posture is changed from supine to lateral, obstruction due to structures such as tongue base and larynx improves dramatically. Obstruction in lateral position is mostly due to obstruction at the oropharyngeal LWs. Therefore, position dependency is mostly determined by LW collapsibility. Evaluating the changes of the upper airway according to sleep position can further characterize the upper airway collapsibility and can be used for tailored treatment planning.

Structural analysis of muscarinic acetylcholine receptor type 1 intracellular loop 3 by hydrogen/deuterium exchange mass spectrometry.

G protein-coupled receptors (GPCRs) perform vital signaling functions and are involved in various diseases, making GPCRs major drug targets. GPCRs have seven α-helical transmembrane domains connected by three extracellular loops (ECLs) and three intracellular loops (ICLs). Among the three ICLs, ICL3 has been reported to have a critical function in interacting with downstream signaling molecules. Despite its important role in GPCR signaling, the structure of ICL3 has not been fully defined. In the present study, we used muscarinic acetylcholine receptor type 1 (M1) as a model system to analyze the structure of ICL3. Optimized purification conditions for M1_ICL3 comprised His-tag affinity purification and solubilization with n-dodecyl-b-D-maltopyranoside. Purified M1_ICL3 was analyzed using circular dichroism and hydrogen/deuterium exchange mass spectrometry; the results of these analyses suggested that M1_ICL3 is disordered and flexible.

Concomitant replacement of the dilated ascending aorta during aortic valve replacement; does it increase the perioperative morbidity and mortality risks?

BACKGROUND: Concerns of increased surgical risks with ascending aortic replacement have led surgeons to manage post-stenotic aortic dilatation more conservatively during aortic valve replacement (AVR). The present study aimed to assess the prognostic implications and surgical risks of replacing the dilated aorta during AVR. METHODS: Between January 1999 and March 2010, 134 patients who received surgery for aortic stenosis and post-stenotic dilatation (aorta size ≥40 mm) were included in the present study. AVR was performed in 92 patients (AVR group) while aortic valve and ascending aorta replacement (AVR + aorta group) were performed in 42 patients. Overall survival was compared between the two groups using Cox proportional hazard model after adjustment with inverse-probability-of-treatment weighting. RESULTS: The mean follow-up duration was 3.5 ± 3 years. There were no significant differences in the operative mortality and morbidity between the two groups. The late cardiac deaths were also not significantly different between the two groups (p = 1.00). In the AVR group, the ascending aortic expansion rate which was 0.18 mm/year over a mean follow-up duration of 2.3 ± 2.2 years by echocardiography showed a positive correlation with time (r = 0.3, p = 0.08). A relatively greater aortic expansion rate was identified as a risk factor for late mortality (p = 0.015, HR 1.08 (CI: 1.02 to 1.15). CONCLUSIONS: Concomitant replacement of the dilated ascending aorta during AVR did not increase the immediate postoperative morbidity or mortality risks and tended to exert a long-term beneficial effect on the risk of late mortality.

Is pylorospasm a cause of delayed gastric emptying after pylorus-preserving pancreaticoduodenectomy?

BACKGROUND: Delayed gastric emptying (DGE) occurs in 14% to 61% of patients after pylorus-preserving pancreaticoduodenectomy, but its pathogenesis is unclear. We hypothesized that DGE may be due to pylorospasm secondary to vagal injuries at operation and may be preventable by the addition of pyloromyotomy. METHODS: Patients operated on consecutively between April 2000 and August 2003 were studied. Pyloromyotomy was of the Fredet-Ramstedt type combined with antroplasty. DGE-free recovery was defined as tolerance of a diet for three successive days by postoperative day 8. The symptom of nausea was used as a basis for nasogastric tube removal and diet resumption. A gastric emptying test (GET) with solid food was obtained. Patients with difficulty swallowing were fed via a feeding tube. RESULTS: There were 47 patients. Two patients were excluded because of death (n = 1) and ileus with pancreatic fistula (n = 1). Diagnoses were pancreatic cancer (n = 23), chronic pancreatitis (n = 11), ampullary cancer (n = 5), mucinous cystic neoplasm (n = 5), and duodenal villous adenoma (n = 3). Median times to nasogastric tube removal, start of liquid diet, and start of solid diet were postoperative days 2, 3, and 5, respectively. Two patients had tube feedings. Preoperative GET was abnormal in 51%, and postoperative GET was abnormal in 37%. The average length of stay was 9.5 days (median, 7 days). DGE occurred in only one patient (2.2%). There were no late complications during a 6-month follow-up. CONCLUSIONS: The addition of pyloromyotomy to pylorus-preserving pancreaticoduodenectomy is effective in preventing DGE. Results are supportive of the hypothesis that DGE may be caused by operative injuries of the vagus innervating the pyloric region.