Serum deprivation-response protein regulates aldehyde dehydrogenase 1 through integrin-linked kinase signaling in endometrioid carcinoma cells

Enhancing prognostic insights: myometrial invasion patterns in endometrial carcinoma, with emphasis on MELF pattern-a comprehensive review and meta-analysis

PURPOSE

The microcystic, elongated, and fragmented (MELF) pattern, characterized by myxoid and inflamed stroma, is readily identifiable as a form of myometrial infiltration. This meta-analysis endeavors to assess the prognostic significance of MELF infiltration patterns in patients diagnosed with endometrial cancer.

METHODS

A comprehensive literature search, spanning until 11 October 2023, across PubMed , Embase , Cochrane , and Web of Science databases, identified 23 relevant studies involving 5199 patients. Data analysis was performed using Stata 16.0.

RESULTS

Analysis indicates that MELF infiltration predicts a higher risk of lymph node metastasis in endometrial cancer patients [hazard ratios (HR) = 5.05; 95% confidence interval (CI), 3.62-7.05; P  < 0.05]. Notably, this association remains consistent across various patient demographics, analytical approaches, study designs, and treatment modalities. However, MELF infiltration does not significantly correlate with recurrence (HR = 1.05; 95% CI, 0.73-1.52; P  > 0.05), overall survival (HR = 1.24; 95% CI, 0.91-1.68; P  > 0.05), or disease-free survival (HR = 1.40; 95% CI, 0.85-2.28; P  > 0.05).

CONCLUSION

While MELF infiltration heightens the risk of lymph node metastasis in endometrial cancer, its impact on recurrence, overall survival, and disease-free survival remains statistically insignificant.

Relation of squamous differentiation in endometrioid carcinoma with MELF pattern to a high ratio of lymph node metastasis

One of the known histological patterns of endometrioid carcinoma (EC) in uterine corpus cancer is MELF (microcystic, elongated, and fragmented). MELF is associated with lymphovascular invasion and lymph node metastasis. Besides MELF, it is also known that squamous differentiation (SD) often occurs in EC. SD is known to be no significant difference in the frequency of lymph node metastasis in EC. However, there have been no previous reports on the association between MELF and SD. In this research, we investigated the presence of SD in MELF using an antibody to CK5. We examined 28 cases of EC with MELF pattern, in which 15 cases showed SD. Moreover, the relation of lymph node metastasis to SD was examined. Lymph node dissection was performed in 27 out of 28 cases. Among them, 12 cases showed lymph node metastasis. The ratio of lymph node metastasis was significantly higher in EC with SD (64.3 %, 9 in 14 cases) than EC without SD (23.1 %, 3 in 13 cases). In this study, we first showed the association between SD and MELF and that MELF with SD is associated with a high ratio of lymph node metastasis. It is clinically relevant to recognize that MELF with SD is aggressive with a high ratio of lymph node metastasis.

Serum deprivation protein response intervenes in the proliferation, motility, and extracellular matrix production in keloid fibroblasts by blocking the amplification of TGF-β1/SMAD signal cascade via ERK1/2

Keloid formation has been linked to abnormal fibroblast function, such as excessive proliferation and extracellular matrix (ECM) production. Serum deprivation protein response (SDPR) is a crucial regulator of cellular function under diverse pathological conditions, yet its role in keloid formation remains unknown. The current work investigated the function of SDPR in regulating the proliferation, motility, and ECM production of keloid fibroblasts (KFs), as well as to decipher the mechanisms involved. Analysis of RNA sequencing data from the GEO database demonstrated significant down-regulation of SDPR in KF compared to normal fibroblasts (NFs). This down-regulation was also observed in clinical keloid specimens and isolated KFs. Overexpression of SDPR suppressed the proliferation, motility, and ECM production of KFs, while depletion of SDPR exacerbated the enhancing impact of TGF-β1 on the proliferation, motility, and ECM production of NFs. Mechanistic studies revealed that SDPR overexpression repressed TGF-β/Smad signal cascade activation in KFs along with decreased levels of phosphorylated Samd2/3, while SDPR depletion exacerbated TGF-β/Smad activation in TGF-β1-stimulated NFs. SDPR overexpression also repressed ERK1/2 activation in KFs, while SDPR depletion exacerbated ERK1/2 activation in TGF-β1-stimulated NFs. Inhibition of ERK1/2 abolished SDPR-depletion-induced TGF-β1/Smad activation, cell proliferation, motility, and ECM production in NFs. In conclusion, SDPR represses the proliferation, motility, and ECM production in KFs by blocking the TGF-β1/Smad pathway in an ERK1/2-dependent manner. The findings highlight the role of SDPR in regulating abnormal behaviors of fibroblasts associated with keloid formation and suggest it as a potential target for anti-keloid therapy development.

Endocervical Adenocarcinoma Showing Microcystic, Elongated, and Fragmented (MELF) Pattern of Stromal Invasion: A Single-Institutional Analysis of 10 Cases with Comprehensive Clinicopathological Analyses and Ki-67 Immunostaining

Microcystic, elongated, and fragmented (MELF) pattern of invasion has seldom been documented in endocervical adenocarcinoma (EAC). The aim of this study was to analyze the clinicopathological characteristics of EAC showing MELF pattern. We collected the clinicopathological information of 10 cases of EAC with the MELF pattern and conducted polymer-based immunostaining for Ki-67 (dilution 1:200, clone MIB-1) on these cases. Ki-67 expression was assessed using the average estimation within the hotspot method. All tumors were human papillomavirus-associated EAC with Silva pattern C. All except one tumor exceeded 3 cm in size. Five tumors involved the entire thickness of the cervical stroma, and four tumors extended into the parametrium. Lymphovascular space invasion was identified in six cases. Two patients developed metastatic recurrences in the para-aortic lymph nodes and lungs, respectively. The MELF area showed significantly lower Ki-67 labelling index than that of a conventional tumor area. We confirmed our previous observation that the MELF area displayed lower proliferative activity than the conventional tumor area of EAC. We also demonstrated that patients with EAC showing MELF pattern had several adverse clinicopathological characteristics reflecting aggressive behavior. On the other hand, since the frequencies of post-operative recurrence and disease-related mortality that occurred during the follow-up period were relatively low, further investigations are warranted to clarify the prognostic value of MELF pattern in EAC patients.

Tumor heterogeneity from the viewpoint of pathologists

Morphological and functional heterogeneity are found in tumors, with the latter reflecting the different levels of resistance against antitumor therapies. In a therapy-resistant subpopulation, the expression levels of differentiation markers decrease, and those of immature markers increase. In addition, this subpopulation expresses genes involved in drug metabolism, such as aldehyde dehydrogenase 1A1 (ALDH1A1). Because of their similarity to stem cells, cells in the latter therapy-resistant subpopulation are called cancer stem cells (CSCs). Like normal stem cells, CSCs were originally thought not to arise from non-CSCs, but this hierarchical model is too simple. It is now believed that CSCs are generated from non-CSCs. The plasticity of tumor phenotypes between CSCs and non-CSCs causes difficulty in completely curing tumors. In this review, focusing on ALDH1A1 as a marker for CSCs or immature tumor cells, the dynamics of ALDH1A1-expressing tumor cells and their regulatory mechanisms are described, and the plausible regulatory mechanisms of plasticity of ALDH1A1 expression phenotype are discussed. Genetic mutations are a significant factor for tumorigenesis, but non-mutational epigenetic reprogramming factors yielding tumor heterogeneity are also crucial in determining tumor characteristics. Factors influencing non-mutational epigenetic reprogramming in tumors are also discussed.

ALDH1: A potential therapeutic target for cancer stem cells in solid tumors

Solid tumors can be divided into benign solid tumors and solid malignant tumors in the academic community, among which malignant solid tumors are called cancers. Cancer is the second leading cause of death in the world, and the global incidence of cancer is increasing yearly New cancer patients in China are always the first. After the concept of stem cells was introduced in the tumor community, the CSC markers represented by ALDH1 have been widely studied due to their strong CSC cell characteristics and potential to be the driving force of tumor metastasis. In the research results in the past five years, it has been found that ALDH1 is highly expressed in various solid cancers such as breast cancer, lung cancer, colorectal cancer, liver cancer, gastric cancer, cervical cancer, esophageal cancer, ovarian cancer, head,and neck cancer. ALDH1 can activate and transform various pathways (such as the USP28/MYC signaling pathway, ALDH1A1/HIF-1α/VEGF axis, wnt/β-catenin signaling pathway), as well as change the intracellular pH value to promote formation and maintenance, resulting in drug resistance in tumors. By targeting and inhibiting ALDH1 in tumor stem cells, it can enhance the sensitivity of drugs and inhibit the proliferation, differentiation, and metastasis of solid tumor stem cells to some extent. This review discusses the relationship and pathway of ALDH1 with various solid tumors. It proposes that ALDH1 may serve as a diagnosis and therapeutic target for CSC, providing new insights and new strategies for reliable tumor treatment.

Nicotinamide N-methyltransferase is related to MELF pattern invasion in endometrioid carcinoma

Grade 1 (G1) endometrioid carcinoma (EC) is relatively a good prognosis. However, in a minority of cases, G1 shows an aggressive histological pattern known as the microcystic, elongated, and fragmented (MELF) pattern. We previously reported that EC with high expression levels of S100A4 and serum deprivation-response protein (SDPR) was related to MELF pattern invasion. However, the molecular features of the invasive front area of the MELF pattern have not been investigated. In this study, we searched for genes preferentially expressed in the invasive front area of EC with the MELF pattern using laser microdissection and RNA sequencing, and showed that nicotinamide N-methyltransferase (NNMT) is related to MELF pattern invasiveness. Immunohistochemical analyses confirmed high NNMT expression in the invasive front area of the MELF pattern. Moreover, NNMT promoted migration, invasion, colony formation, epithelial-mesenchymal transition (EMT), and chemoresistance using EC cell lines. We speculate that depletion of NNMT promotes histone methylation and leads to tumor suppression because NNMT consumes S-adenosyl methionine (SAM), which is an essential methylation cofactor. NNMT knockout cells showed enhanced expression of H3K9me2. RNA sequencing using NNMT knockout cell lines suggested that methylation of H3K9 leads to repression of the transcription of various oncogenic genes. Our findings demonstrate the possibility that NNMT inhibitors, which are expected to be used for the treatment of metabolic disorders, would be effective for the treatment of aggressive EC. This is the first report of gene analyses focusing on the morphological changes associated with MELF pattern invasion of EC.

CAVIN2 is frequently silenced by CpG methylation and sensitizes lung cancer cells to paclitaxel and 5-FU

Aim: To explore the biological functions and clinical significance of CAVIN2 in lung cancer. Materials & methods: Methylation-specific PCR was used to measure promoter methylation of CAVIN2. The function of CAVIN2 was tested by Cell Counting Kit-8, colony formation, Transwell, flow cytometric analysis, acridine orange/ethidium bromide, chemosensitivity assay and xenograft assay. Results: CAVIN2 is significantly downregulated by promoter methylation in lung cancer. CAVIN2 overexpression inhibits lung cancer cell migration and invasion. Furthermore, ectopic expression of CAVIN2 inhibits cell proliferation in vivo and in vitro by inducing G2/M cell cycle arrest, which sensitizes the chemosensitivity of lung cancer cells to paclitaxel and 5-fluorouracil, but not cisplatin. Conclusion: CAVIN2 is a tumor suppressor in non-small-cell lung cancer and can sensitize lung cancer cells to paclitaxel and 5-fluorouracil.

Applications of CRISPR-Cas9 in gynecological cancer research

Gynecological cancers pose a significant threat to women's health worldwide, with cervical cancer, ovarian cancer, and endometrial cancer having high incidences. Current gynecological cancer treatment methods mainly include surgery, chemotherapy, radiotherapy, and chemoradiotherapy. The CRISPR-Cas9 gene editing technology as a new therapeutic method has shown tremendous effect in the treatment of other cancers, promoting research on its potential therapeutic effect in gynecological cancer. In this article, we reviewed the current research status of CRISPR-Cas9 technology in gynecological cancer, focusing on the importance of studying the mechanism of CRISPR-Cas9 in gynecological cancer treatment, thereby laying a foundation for further research on its clinical application.

Proteomic Technology "Lens" for Epithelial-Mesenchymal Transition Process Identification in Oncology

The epithelial-mesenchymal transition (EMT) is a complex transformation process that induces local and distant progression of many malignant tumours. Due to its complex array of proteins that are dynamically over-/underexpressed during this process, proteomic technologies gained their place in the EMT research in the last years. Proteomics has identified new molecular pathways of this process and brought important insights to develop new therapy targets. Various proteomic tools and multiple combinations were developed in this area. Out of the proteomic technology armentarium, mass spectrometry and array technologies are the most used approaches. The main characteristics of the proteomic technology used in this domain are high throughput and detection of minute concentration in small samples. We present herein, using various proteomic technologies, the identification in cancer cell lines and in tumour tissue EMT-related proteins, proteins that are involved in the activation of different cellular pathways. Proteomics has brought besides standard EMT markers (e.g., cell-cell adhesion proteins and transcription factors) other future potential markers for improving diagnosis, monitoring evolution, and developing new therapy targets. Future will increase the proteomic role in clinical investigation and validation of EMT-related biomarkers.

Unique Molecular Features in High-Risk Histology Endometrial Cancers

Endometrial cancer is the most common gynecologic malignancy in the United States and the sixth most common cancer in women worldwide. Fortunately, most women who develop endometrial cancer have low-grade early-stage endometrioid carcinomas, and simple hysterectomy is curative. Unfortunately, 15% of women with endometrial cancer will develop high-risk histologic tumors including uterine carcinosarcoma or high-grade endometrioid, clear cell, or serous carcinomas. These high-risk histologic tumors account for more than 50% of deaths from this disease. In this review, we will highlight the biologic differences between low- and high-risk carcinomas with a focus on the cell of origin, early precursor lesions including atrophic and proliferative endometrium, and the potential role of stem cells. We will discuss treatment, including standard of care therapy, hormonal therapy, and precision medicine-based or targeted molecular therapies. We will also discuss the impact and need for model systems. The molecular underpinnings behind this high death to incidence ratio are important to understand and improve outcomes.

Serum deprivation-response protein regulates aldehyde dehydrogenase 1 through integrin-linked kinase signaling in endometrioid carcinoma cells

Endometrioid carcinoma (EC) is one of the most common malignancies of the female genital system. We reported previously that aldehyde dehydrogenase 1 (ALDH1), a predominant isoform of the ALDH family in mammals and a potential marker of normal and malignant stem cells, is related to the tumorigenic potential of EC. We compared the levels of various proteins in human EC cells with high and low ALDH1 expression using shotgun proteomics and found that serum deprivation‐response protein (SDPR) was preferentially expressed in cells with high ALDH1 expression. Also known as cavin‐2, SDPR is a member of the cavin protein family, which is required for the formation of caveolae. Using SDPR‐knockout EC cells generated using the CRISPR/Cas9 system, we revealed that SDPR was correlated with invasion, migration, epithelial‐mesenchymal transition, and colony formation, as well as the expression of ALDH1. RNA sequencing showed that integrin‐linked kinase (ILK) signaling is involved in the effect of SDPR on ALDH1. Immunohistochemical analysis revealed that the localization of ILK at the cell cortex was disrupted by SDPR knockout, potentially interfering with ILK signaling. Moreover, immunohistochemical analysis of clinical samples showed that SDPR is related to histological characteristics associated with invasiveness, such as poor differentiation, lymphatic invasion, and the microcystic, elongated, and fragmented histopathological pattern. This is, to our knowledge, the first report that SDPR is related to tumor progression.