Role of apoptotic, autophagic and senescence pathways in minor salivary gland adenoid cystic carcinoma

Adenoid cystic carcinoma: insights from molecular characterization and therapeutic advances

Adenoid cystic carcinoma (ACC) is a malignant tumor primarily originating from the salivary glands, capable of affecting multiple organs. Although ACC typically exhibits slow growth, it is notorious for its propensity for neural invasion, local recurrence, and distant metastasis, making it a particularly challenging cancer to treat. The complexity of ACC's histological and molecular features poses significant challenges to current treatment modalities, which often show limited effectiveness. Recent advancements in single-cell RNA-sequencing (scRNA-seq) have begun to unravel unprecedented insights into the heterogeneity and subpopulation diversity within ACC, revealing distinct cellular phenotypes and origins. This review delves into the intricate pathological and molecular characteristics of ACC, focusing on recent therapeutic advancements. We particularly emphasize the insights gained from scRNA-seq studies that shed light on the cellular landscape of ACC, underscoring its heterogeneity and pathobiology. Moreover, by integrating analyses from public databases, this review proposes novel perspectives for advancing treatment strategies in ACC. This review contributes to the academic understanding of ACC by proposing novel therapeutic approaches informed by cutting-edge molecular insights, paving the way for more effective, personalized therapeutic approaches for this challenging malignancy.

Evaluation of Some Prognostic Biomarkers in Human Papillomavirus-Related Multiphenotypic Sinonasal Carcinoma

Background

Human papillomavirus (HPV)-related multi phenotypic sinonasal carcinoma (HMSC) is a recently described tumor subtype with an unknown prognosis, often misdiagnosed with other sinonasal carcinomas, and associated with high-risk HPV (HR-HPV). The present study aimed to evaluate the expression of vascular endothelial growth factor (VEGF), Bcl-2-associated X protein (BAX), epidermal growth factor receptors (EGFR), ProExTMC, and human telomerase reverse transcriptase (hTERT) and assess their association with survival and clinicopathological characteristics.

Methods

Between 2017 and 2022, 40 HMSC patients underwent surgical resection at the School of Medicine, Zagazig University Hospitals (Zagazig, Egypt). Tissue samples were examined for the presence of HR-HPV; absence of myeloblastosis (MYB), MYB proto-oncogene like 1 (MYBL1), and nuclear factor I/B (NFIB) fusions and the presence of myoepithelial proteins (calponin, S100, SMA), squamous differentiation markers (p63, p40, calponin), VEGF, BAX, ProExTMC, and hTERT by immunohistochemistry. All patients were followed up for about 54 months until death or the last known survival data. Data were analyzed using the Chi square test and Kaplan-Meier method.

Results

The expression of VEGF, hTERT, and ProExTMC was significantly associated with age, advanced tumor stages, lymph node metastasis, tumor size, mortality, relapse, poor disease-free survival (DFS), and overall survival (OS) (P<0.001). BAX expression was significantly associated with tumor size, age, poor DFS, and relapse (P=0.01, P<0.001, P=0.035, and P=0.002, respectively).

Conclusion

HMSC is strongly associated with HR-HPV. The expression of VEGF, EGFR, BAX, hTERT, and ProExTMC is associated with aggressive malignant behavior, poor survival, and poor prognosis, making them novel prognostic biomarkers for targeted therapeutics in HMSC.

Immunoexpression of Autophagy-Related Proteins in Salivary Gland Tumors: An Exploratory Study

BACKGROUND

Autophagy is a cellular survival mechanism involved in several human diseases, but its participation in the development of salivary gland tumors is not fully understood. This study investigated the immunoexpression of autophagy-related proteins (autophagy-related 7 [Atg7], microtubule-associated protein 1 light chain 3A [LC3A], microtubule-associated protein 1 light chain 3B [LC3B], protein p62 [p62], and phosphorylated mammalian target of rapamycin [p-mTOR]) in pleomorphic adenoma (PA), polymorphous adenocarcinoma (PAC), mucoepidermoid carcinoma (MEC), and adenoid cystic carcinoma (ACC) of salivary glands.

METHODS

Twenty PAs, 20 PACs, 20 MECs, and 14 ACCs were selected. The percentages of cytoplasmic and nuclear positivity for autophagy-related proteins in neoplastic cells were assessed and correlated with histopathological parameters.

RESULTS

Cytoplasmic immunoexpression of Atg7 was observed in all groups, with high median percentages of positivity. Regarding LC3A and LC3B, cytoplasmic immunoexpression was found in most PACs (95%) and in all cases of PA, MEC and ACC, with the highest percentages of positivity in PACs and PAs (p < 0.005). ACCs exhibited lower cytoplasmic immunoexpression of p-mTOR (p < 0.005) and lower nuclear expression of p62 (p < 0.05) when compared to PAs, PACs and MECs. Low nuclear immunoexpression of Atg7, LC3A and p-mTOR and absence of nuclear staining for LC3B were observed in all groups. Regarding histopathological parameters of PAs, MECs and ACCs, there were no significant differences in the expression of autophagy-related proteins. In all groups, positive correlations were observed between the immunoexpression of some autophagy-related proteins (p < 0.05).

CONCLUSIONS

The results suggest the participation of autophagy in the pathogenesis of PA, PAC, MEC, and ACC of salivary glands. Upregulation of autophagy and reduced nuclear translocation of p62 may contribute to the aggressive biological behavior of salivary gland ACC.

Adenoid Cystic Carcinoma of Salivary Glands: A Ten-Year Review and an Assessment of the Current Management, Surgery, Radiotherapy, and Chemotherapy

Adenoid cystic carcinoma (ACC) is a rare cancer that arises from the salivary glands and other sites in the body, such as the lung and breast. Although the tumor accounts for 10% of all salivary gland malignancies, it only accounts for 1% of head and neck malignancies. It can affect both major and minor salivary glands; here, it is called salivary gland adenoid cystic carcinoma or SACC, with a slight predilection to the latter, and commonly manifests between the 6_th and 7_th decades of life. The disease also shows a slight female predilection, with a reported female to male ratio of 3 : 2. Lesions of SACC are often insidious and slow-growing, and symptoms such as pain and altered sensation are frequently associated with advanced stages of the disease. Salivary adenoid cystic carcinoma is characterized by perineural invasion (PNI), a distinctive feature that potentially plays a significant role in the tumor's relapse and recurrence, which is approximately 50%. The disease is not prevalent, and its etiopathogenesis is poorly understood, although several genetic patterns and biomarkers have been linked to its initiation and/or progression. The discovery of these mutations and biomarkers has encouraged several clinical studies to use therapeutic agents to target the specific receptors on the cancer cells to potentially prevent further proliferation of the tumor cells and metastasis of the disease. Diagnosis of SACC is often challenging and frequently requires a combination of clinical examination, imaging, and histopathology. Management of SACC is primarily surgical excision, while radiotherapy has shown to be effective in improving local control in cases with microscopic residual disease. However, treatment of recurrent or metastatic tumors by radiotherapy with or without chemotherapy has so far shown limited success. The aim of this thesis is to provide an update of literature on SACC with a particular focus on the latest management approaches and future trends.

Cellular senescence in cancer: clinical detection and prognostic implications

Cellular senescence is a state of stable cell-cycle arrest with secretory features in response to cellular stress. Historically, it has been considered as an endogenous evolutionary homeostatic mechanism to eliminate damaged cells, including damaged cells which are at risk of malignant transformation, thereby protecting against cancer. However, accumulation of senescent cells can cause long-term detrimental effects, mainly through the senescence-associated secretory phenotype, and paradoxically contribute to age-related diseases including cancer. Besides its role as tumor suppressor, cellular senescence is increasingly being recognized as an in vivo response in cancer patients to various anticancer therapies. Its role in cancer is ambiguous and even controversial, and senescence has recently been promoted as an emerging hallmark of cancer because of its hallmark-promoting capabilities. In addition, the prognostic implications of cellular senescence have been underappreciated due to the challenging detection and sparse in and ex vivo evidence of cellular senescence in cancer patients, which is only now catching up. In this review, we highlight the approaches and current challenges of in and ex vivo detection of cellular senescence in cancer patients, and we discuss the prognostic implications of cellular senescence based on in and ex vivo evidence in cancer patients.

Paired related homeobox 1 attenuates autophagy via acetyl-CoA carboxylase 1-regulated fatty acid metabolism in salivary adenoid cystic carcinoma

Autophagy can affect the invasion and metastasis of carcinoma. Our previous study has shown that invasion and epithelial‐mesenchymal transition in salivary adenoid cystic carcinoma (SACC) can be promoted by the metabolic reprogramming of free fatty acids (FFAs). However, the effect of FFA metabolism on autophagy in SACC remains unknown. In this study, we showed that overexpression of paired related homeobox 1 (PRRX1) reduced the number of autophagosomes and decreased the expression of LC3 and Beclin‐1 in SACC patients and SACC‐83 cells in vitro. Moreover, PRRX1‐mediating FFA reprogramming triggered to autophagy via regulating acetyl‐CoA carboxylase 1 (ACC1), leading to invasion and migration in SACC.

Autophagy upregulation may explain inhibition of oral carcinoma in situ by photobiomodulation in vitro

There is currently no clear understanding on the pathways involved in the process of cell inhibition by photobiomodulation (PBM). The present study evaluated the influence of PBM on the expression of autophagy markers in vitro in an in situ model of oral carcinoma. Oral squamous cell carcinoma (Cal27) and stromal fibroblasts (FG) cultures were used. The independent variables were 'cell type' (FG and CAL27) 'culture condition' (monocultures or co-cultures) and PBM (placebo and 36 J/cm²). The cultures were irradiated from a red LED source for mRNA expression and protein expression analyses. The autophagy markers evaluated were Beclin-1, LC3B and p62 as well as adjuvant markers (BAX Bcl-2, VEGF, CD105, CD34, PRDX1, PRDX4 and GRP78). The Cal27 cells upregulated the autophagy markers upon exposure to PBM both at the mRNA and protein expression levels, providing evidence to explain malignant cell inhibition by PBM.

Regulatory effect of LncRNA DRAIC/miR-149-5p/NFIB molecular network on autophagy of esophageal cancer cells and its biological behavior

OBJECTIVE

This experiment will explore the effect of LncRNA DRAIC/miR-149-5p/NFIB molecular network on esophageal cancer (EC) cells' biological behavior and autophagy.

METHODS

We bought human EC cells and normal esophageal epithelial cells HEEC. DRAIC, miR-149-5p and NFIB protein expression were tested. The low expression plasmid of DRAIC and empty vector of DRAIC, miR-149-5p miR-mimics, miR-149-5p inhibitors and negative control groups, NFIB high expression plasmid, NFIB low expression plasmid and empty vector were transfected into EC cells (Eca-109 and EC9706) to detect changes in cell biological behavior and autophagy protein expression. The targeted relationship between DRAIC/miR-149-5p/NFIB was verified through dual-luciferase report and pull-down experiment.

RESULTS

DRAIC and NFIB showed high expression in EC cells, while miR-149-5p showed low expression. Down-regulating DRAIC, NFIB and over-expressing miR-149-5p can inhibit EC cells' proliferation and invasion, and improve apoptosis and autophagy. Dual-luciferase report and pull-down experiment confirmed that DRAIC targeted miR-149-5p regulation, and down-regulating DRAIC could reverse miR-149-5p inhibitor's effect on the biological behavior of EC cells. However, dual-luciferase report revealed that miR-149-5p directly targeted NFIB, and miR-149-5p inhibitor could weaken the effect of down-regulating NFIB on apoptosis and autophagy of EC cells. Moreover, DRAIC has an effect on the autophagy of EC cells through miR-149-5p/NFIB.

CONCLUSION

LncRNA DRAIC is relevant to cell biology and autophagy of EC. In the future, DRAIC may be developed as a key gene for EC diagnosis and treatment.