Lacrimal gland dysfunction causes dry eye disease (DED) due to decreased tear production. Aqueous-deficient DED is more prevalent in women, suggesting that sexual dimorphism of the human lacrimal gland could be a potential cause. Sex steroid hormones are a key factor in the development of sexual dimorphism. This study aimed to quantify estrogen receptor (ER) and androgen receptor (AR) expression in the human lacrimal gland and compare it between sexes. RNA was isolated from 35 human lacrimal gland tissue samples collected from 19 cornea donors. AR, ERα, and ERβ mRNA was identified in all samples, and their expression was quantified using qPCR. Immunohistochemical staining was performed on selected samples to evaluate protein expression of the receptors. ERα mRNA expression was significantly higher than the expression of AR and ERβ. No difference in sex steroid hormone (SSH) receptor mRNA expression was observed between sexes, and no correlation was observed with age. If ERα protein expression is found to be concordant with mRNA expression, it should be investigated further as a potential target for hormone therapy of DED. Further research is needed to elucidate the role of sex steroid hormone receptors in sex-related differences of lacrimal gland structure and disease.

Sexual dimorphism significantly impacts the lacrimal gland’s structure, function, and ageing processes, playing an important role in dry eye disease (DED) pathophysiology. This multifactorial disorder, characterised by tear film instability, inflammation, and visual impairment, disproportionately affects women, especially after menopause. It highlights the interplay between sex steroid hormones, lacrimal gland function, and environmental factors. Systemic and local androgens are vital for maintaining lacrimal gland health and tear production, while the role of oestrogens remains less clear. Evidence suggests dose and context-dependent effects on inflammation and glandular function. Histopathological and molecular studies reveal significant sex differences in the lacrimal gland, with women exhibiting more pronounced age-related degenerative changes, including fibrosis and acinar atrophy, contributing to their increased susceptibility to DED. Despite these findings, the underlying mechanisms connecting sex steroid hormones, receptor expression, and local tissue regulation to these disparities remain poorly understood, highlighting the need for further research. This review synthesises the current knowledge of sex-specific differences in the lacrimal gland, emphasising the importance of integrating systemic and local biomarkers, histological data, and molecular insights into personalised therapeutic strategies. By tailoring treatments to patients’ unique hormonal and molecular profiles, personalised medicine has the potential to transform DED management, addressing unmet clinical needs and improving outcomes.

To assess sex-related differences in the pathohistological features of the human lacrimal gland and to investigate age- and sex-related differences in stereologically measured volume density of the secretory tissue, connective tissue, and fat.We performed ...

Tumor necrosis is a recurrent characteristic of head and neck squamous cell carcinomas (HNSCCs). There is a need for more investigations on the influence of biomolecules released by these necrotic foci in the HNSCC tumor microenvironment. It is suspected that a fraction of the biomolecules released by necrotic cells are damage-associated molecular patterns (DAMPs), which are known to be natural endogenous ligands of Toll-like receptors (TLRs), including, among others, proteins and nucleic acids. However, there has been no direct demonstration that biomolecules released by HNSCC necrotic cells can activate TLRs. Our aim was to investigate whether some of these molecules could behave as agonists of the TLR3, either in vitro or in vivo. We chose a functional approach based on reporter cell exhibiting artificial TLR3 expression and downstream release of secreted alkaline phosphatase. The production of biomolecules activating TLR3 was first investigated in vitro using three HNSCC cell lines subjected to various pronecrotic stimuli (external irradiation, serum starvation, hypoxia and oxidative stress). TLR3 agonists were also investigated in necrotic tumor fluids from five oral cancer patients and three mouse tumor grafts. The release of biomolecules activating TLR3 was demonstrated for all three HNSCC cell lines. External irradiation was the most consistently efficient stimulus, and corresponding TLR3 agonists were conveyed in extracellular vesicles. TLR3-stimulating activity was detected in the fluids from all five patients and three mouse tumor grafts. In most cases, this activity was greatly reduced by RNAse pretreatment or TLR3 blocking antibodies. Our data indicate that TLR3 agonists are consistently present in necrotic fluids from HNSCC cells and mainly made of dsRNA fragments. These endogenous agonists may induce TLR3, which might lead to a protumorigenic effect. Regarding methodological aspects, our study demonstrates that direct investigations—including functional testing—can be performed on necrotic fluids from patient tumors.

Refractory neuropathic pain of the head and neck remains a major clinical challenge, particularly when mediated through the cervicotrigeminal complex (CTC), a unique anatomical hub integrating trigeminal and upper cervical nociceptive inputs. This narrative review synthesizes neuroanatomical, pathophysiological, and clinical evidence to provide a unifying framework for diagnosis and management. A structured search of PubMed, Scopus, and Web of Science identified English-language clinical and mechanistic studies addressing CTC-mediated pain, with case reports excluded unless mechanistically informative. We propose multidimensional refractoriness criteria that integrate pharmacological non-response, failed interventional strategies, and objective functional impairment. Current treatments span pharmacotherapy, peripheral interventions (nerve blocks, radiofrequency ablation), and neuromodulation at multiple network levels (occipital nerve stimulation, spinal cord stimulation, motor cortex stimulation, deep brain stimulation). Non-invasive approaches such as rTMS, tDCS, and vagus nerve stimulation are emerging but remain investigational. Advances in imaging and neurophysiological biomarkers now permit greater precision in detecting CTC dysfunction and tailoring therapy. By combining anatomical precision, mechanistic insight, and multidisciplinary strategies, this review proposes a clinically actionable definition of refractoriness and supports a stepwise, mechanism-based approach to therapy. CTC emerges as a targetable hub for diagnostic and therapeutic strategies in refractory head and neck pain.

Background: Non-smoking, non-drinking (NSND) oral squamous cell carcinoma (OSCC) is increasingly recognized, yet its clinicopathologic and immune-related correlates remain incompletely defined. Methods: We retrospectively studied 243 surgically treated patients with previously untreated primary OSCC (2011–2020). Patients were classified as NSND or smoking and/or drinking (SD). Immune-modulating conditions and preoperative systemic immune–inflammatory indices (NLR, LMR, SIRI, AISI) were assessed, and overall (OS) and disease-specific survival (DSS) were analyzed. Results: Eighty-five patients (35.0%) were NSND. NSND patients were more often female (58.8% vs. 12.7%) and slightly older (median 54 vs. 50 years). Subsite distribution differed (p < 0.001): tongue (52.9%), buccal mucosa (15.3%), and floor of mouth (3.5%) in NSND versus a predominance of floor of mouth tumors in SD (34.8%). NSND tumors showed smaller diameter, lower depth of invasion, less perineural invasion (40.5% vs. 55.1%), and more frequent inflammatory infiltrate (73.8% vs. 60.1%). Immune-modulating conditions were enriched in NSND (67.1% vs. 17.7%; p < 0.001; adjusted OR 6.25, 95% CI 3.23–12.11), particularly among NSND patients >50 years (79.2%). NSND patients showed lower NLR (p = 0.01), lower SIRI and AISI (p < 0.001), and higher LMR (p < 0.001). Median OS was 81.2 months; NSND showed a trend toward improved OS (p = 0.083) and improved OS after age/sex adjustment (HR 0.64, 95% CI 0.42–0.98), but not after full clinicopathologic adjustment; DSS did not differ (p = 0.59). Conclusions: NSND OSCC exhibits a distinct clinicopathologic presentation and is strongly associated with immune-modulating comorbidity and lower tumor-associated systemic inflammatory indices, consistent with an immune-modulated clinical phenotype.