Nectin-4 expression in a subset of cutaneous adnexal carcinomas: A potential target for therapy with enfortumab vedotin

BACKGROUND

Enfortumab vedotin (EV) is an antibody-drug conjugate directed against Nectin-4 that is used to treat urothelial carcinoma. Nectin-4 is inherently expressed in the skin and adnexal structures. Since therapeutic options for cutaneous adnexal carcinomas are limited, we sought to evaluate Nectin-4 expression in adnexal carcinomas and benign adnexal neoplasms to identify tumors that are potentially targetable with EV.

METHODS

Eight sebaceous carcinomas (seven periocular and one lymph node metastasis), eight digital papillary adenocarcinomas, seven squamoid eccrine ductal carcinomas, eight poromas, eight trichilemmomas, and seven sebaceous adenomas were subjected to immunohistochemical staining for anti-Nectin-4 antibody. H-scores for Nectin-4 expression were calculated.

RESULTS

Benign adnexal neoplasms had a significantly lower mean (±SD) Nectin-4 H-score (142.6 ± 39.1) than did the adnexal carcinomas (198 ± 90.8; p = 0.006). Nectin-4 was expressed in 91% (21/23) of adnexal carcinomas. Sebaceous carcinomas frequently exhibited high expression of Nectin-4 (88% [7/8]), with a mean (±SD) H-score (258.1 ± 58.4) significantly higher than those for digital papillary adenocarcinomas (197.5 ± 52.5; p = 0.035) and squamoid eccrine ductal carcinomas (131.4 ± 114.1; p = 0.031). Sebaceous carcinomas also had significantly higher H-scores than did sebaceous adenomas (186.4 ± 25.0; p = 0.013).

CONCLUSIONS

Increased Nectin-4 expression in a subset of cutaneous adnexal carcinomas, particularly sebaceous carcinomas, reveals that EV is a potential therapeutic option for these tumors.

CD73 expression defines immune, molecular, and clinicopathological subgroups of lung adenocarcinoma

INTRODUCTION

CD73 is a membrane-bound enzyme crucial in adenosine generation. The adenosinergic pathway plays a critical role in immunosuppression and in anti-tumor effects of immune checkpoint inhibitors (ICI). Here, we interrogated CD73 expression in a richly annotated cohort of human lung adenocarcinoma (LUAD) and its association with clinicopathological, immune, and molecular features to better understand the role of this immune marker in LUAD pathobiology.

MATERIALS AND METHODS

Protein expression of CD73 was evaluated by immunohistochemistry in 106 archived LUADs from patients that underwent surgical treatment without neoadjuvant therapy. Total CD73 (T +) was calculated as the average of luminal (L +) and basolateral (BL +) percentage membrane expression scores for each LUAD and was used to classify tumors into three groups based on the extent of T CD73 expression (high, low, and negative).

RESULTS

CD73 expression was significantly and progressively increased across normal-appearing lung tissue, adenomatous atypical hyperplasia, adenocarcinoma in situ, minimally invasive adenocarcinoma, and LUAD. In LUAD, BL CD73 expression was associated with an increase in PD-L1 expression in tumor cells and increase of tumor-associated immune cells. Stratification of LUADs based on T CD73 extent also revealed that tumors with high expression of this enzyme overall exhibited significantly elevated immune infiltration and PD-L1 protein expression. Immune profiling demonstrated that T-cell inflammation and adenosine signatures were significantly higher in CD73-expressing lung adenocarcinomas relative to those lacking CD73.

CONCLUSION

Our study suggests that higher CD73 expression is associated with an overall augmented host immune response, suggesting potential implications in the immune pathobiology of early stage lung adenocarcinoma. Our findings warrant further studies to explore the role of CD73 in immunotherapeutic response of LUAD.

[Polyneuropathy in critically ill patients: a seldom recognized cause of dependence on mechanical ventilators]

INTRODUCTION

Neuromuscular complications, in a critical care unit, are a cause of morbidity in children and prolonged dependence on a mechanical ventilator. Polyneuropathy of the critical patient is such a complication and is seen in patients on mechanical respiratory assistance.

OBJECTIVE

To discuss the neurological and electrophysiological clinical findings of polyneuropathy of the critical patient.

CLINICAL CASE

We evaluated four patients who initially required mechanical respiratory assistance, three for lung disorders and one for acute encephalopathy, who developed prolonged dependence on mechanical ventilators in the year 1999. In all these patients electromyography showed primary axon nerve disorders with secondary demyelination of all four limbs and phrenic nerve involvement.

CONCLUSIONS

Clinical suspicion and use of suitable electrophysiological techniques permits identification of this condition in the severely ill paediatric patient. Better recognition of the condition and investigation of the etiological factors would help to develop suitable measures for prevention and treatment.

Microtubule-associated protein-2 located in growth regions of rat hippocampal neurons is highly phosphorylated at its proline-rich region

Neuronal morphogenesis is regulated, among other factors, by microtubule-associated proteins (MAPs). A family of these proteins, MAP2, which is very abundant in the mammalian nervous system, has been associated with the formation of neurites at early developmental stages and with the dendritic scaffold upon maturation. The function of MAP2 is regulated by its phosphorylation state. One of the phosphorylation sites that has been described is located in the proline-rich region of the protein. It comprises of the residues 1616-1626 and is specifically recognized by the antibody 305. However, little is known about the functional consequences of its modification in vivo. To gain insight into this, we have analysed the expression levels and intracellular distribution of MAP2 phosphorylated at this site (MAP2-P), in primary cultures of rat hippocampal neurons at different developmental stages. Western blot analysis of hippocampal neuron protein extracts revealed that the ratio of MAP2-P:MAP2 was 4:1 at early developmental stages and became 1:4 at later developmental stages, suggesting a role of such phosphorylated forms of the protein in neuritogenesis. Consistent with this view, immunofluorescence microscopy analysis showed that the ratio MAP2-P:MAP2 was 2 in the neurite growth cones, sites where net elongation takes place. A higher presence of phosphorylated MAP2 was observed in growth regions with higher levels of microfilaments, which may be related with the growth region stability. Indeed, when growth-cone collapse was induced in hippocampal neurons after cytochalasin D treatment, which depolymerizes microfilaments, the ratio MAP2-P:MAP2 in these growing regions decreased down to 1. Finally, acceleration of neuronal maturation induced by the activation of glutamate-receptors triggered a dramatic decrease in the phosphorylation of MAP2 at the site recognized by antibody 305. From these results we suggest that the phosphorylation of MAP2 at its proline-rich region is an important event during neuritogenesis.

Blepharospasm and apraxia of eyelid opening in lithium intoxication

We present the case of a 72-year-old woman with a history of a bipolar mood disorder chronically treated with lithium. Upon having the dose increased, she developed an acute confusional state accompanied by blepharospasm (BS) and apraxia of eyelid opening. Gait instability with frequent falls, pyramid tract signs, and postural tremor in both hands were also evident. On withdrawing lithium, symptoms remitted within 2 weeks. This patient illustrates that BS and apraxia of eyelid opening may be triggered by lithium overdose. Our case warrants the inclusion of lithium in the list of drugs liable to induce such movement disorders.