Caveolin-1-ACE2 axis modulates xenobiotic metabolism-linked chemoresistance in ovarian clear cell carcinoma

Clinicopathological Significance and Prognostic Value of the Caveolae Constitutive Proteins Dynamin-2 and Caveolin-1 in Oral Squamous Cell Carcinoma

BACKGROUND

We investigated the clinicopathological significance of the expression of two caveolae component proteins, dynamin-2 (DNM2) and caveolin-1 (CAV1), in primary tumors of patients with oral squamous cell carcinoma (OSCC).

METHODS

Immunohistochemical staining for DNM2 and CAV1 was performed on resected primary tumor specimens from 80 OSCC patients, and the individual expressions and combined expression status of these proteins were analyzed in relation to clinicopathological factors and prognosis.

RESULTS

We observed that the DNM2 expression was significantly correlated with the OSCC T-classification and the stage, while CAV1 expression was significantly correlated with the mode of invasion and recurrence. Moreover, the combined DNM2/CAV1 expression status was significantly correlated with the T-classification, stage, cell differentiation, and recurrence. In terms of overall survival, the CAV1-positive patients had a significantly poorer prognosis compared to the CAV1-negative patients, and the patients who expressed neither DNM2 nor CAV1 had a significantly better prognosis than those expressing either or both proteins.

CONCLUSION

These results suggest that in OSCC, the expression of DNM2 is involved in tumor growth and the expression of CAV1 is involved in tumor invasion, and DNM2 and/or CAV1 expression affects the progression and prognosis of OSCC. The expressions of DNM2 and CAV1 may therefore be useful markers for OSCC progression and prognosis.

Caveolin-1 modulates cisplatin sensitivity in oral squamous cell carcinoma through ferroptosis

OBJECTIVE

Cisplatin-based chemotherapy is widely used for the treatment of oral squamous cell carcinoma (OSCC), but drug resistance and decreased sensitivity often occur during the treatment, greatly weakening its therapeutic effect. Caveolin-1 (CAV1), a protein related to ferroptosis, is involved in regulating the resistance and sensitivity of various tumor chemotherapies. This study aims to investigate whether CAV1 can regulate the sensitivity of OSCC to cisplatin through ferroptosis.

METHODS

Through bioinformatics analysis, we analyzed the expression of CAV1 in OSCC and its impact on prognosis analyzed the relationship between CAV1 and tumor immune infiltration, and verified the expression of CAV1 in OSCC through immunohistochemistry experiments. We silenced the expression of CAV1 in OSCC cells through lentiviral transfection and evaluated the cell migration and invasion abilities through wound healing and Transwell assays, respectively. CCK8 assay was used to assess the sensitivity of cells to cisplatin, and ferroptosis-related biochemical marker changes were measured. Western blot was performed to detect the expression of ferroptosis-related proteins.

RESULTS

The results revealed a high expression of CAV1 in OSCC, and its high expression predicted poor prognosis in OSCC. CAV1 is associated with drug metabolism pathways in OSCC, and its expression affects the infiltration levels of various immune cells in tumors. Further experiments indicated that CAV1 can inhibit ferroptosis and cisplatin sensitivity in cancer cells, promoting their migration and invasion.

CONCLUSION

CAV1 promotes the progression of OSCC and can affect the sensitivity of cisplatin by regulating cellular ferroptosis.

ACE Loss Drives Renal Cell Carcinoma Growth and Invasion by Modulating AKT-FOXO1

Purpose

Emerging literature links the role of the renin-angiotensin-aldosterone system (RAAS) to the progression of cancers. However, the function of RAAS has not been verified in Clear-cell renal cell carcinoma (ccRCC).

Methods

ACE expression in ccRCC tissues was determined using RT-PCR, Western blot, and immunohistochemistry staining. The clinical significance of ACE was evaluated through Cox regression analysis. To assess the impact of ACE expression on ccRCC cell growth, metastasis, and glucose activity, CCK-8 assays, transwell assays, Seahorse detection, and xenograft models were utilized. The mechanisms of ACE and its upstream and downstream regulatory factors were investigated using RNA-seq, chromatin immunoprecipitation (ChIP), and luciferase reporter assays.

Results

RAAS-related gene Angiotensin-Converting Enzyme (ACE) was significantly under expressed in ccRCC cells and tissues. High ACE expression was positively associated with a favorable prognosis in ccRCC patients. Functional studies showed that ACE overexpression suppressed ccRCC cell line OS-RC-2 and A498 growth, metastasis, and glycolysis activities, while its knockdown had the opposite effect. Mechanistically, ACE inhibited ccRCC progression and epithelial-mesenchymal transition (EMT) by disrupting the AKT-FOXO1 signaling pathway. Furthermore, we provide evidence that ACE could enhance everolimus (approved agent for ccRCC) antitumor effect and ACE expression is transcriptionally regulated by ZBTB26.

Conclusion

Our findings investigated the roles and mechanisms of ACE in ccRCC. ACE inhibits the growth and metastasis of ccRCC cells in vitro and in vivo by promoting FOXO1 expression, which is the downstream target of PI3K-AKT pathway. Thus, this research suggests that ACE may be a promising target for new therapeutic strategy in ccRCC.

Activation of limbal epithelial proliferation is partly controlled by the ACE2-LCN2 pathway

In response to corneal injury, an activation of corneal epithelial stem cells and their direct progeny the early transit amplifying (eTA) cells to rapidly proliferate is critical for proper re-epithelialization. Thus, it is important to understand how such stem/eTA cell activation is regulated. Angiotensin-converting enzyme 2 (ACE2) is predominantly expressed in the stem/eTA-enriched limbal epithelium but its role in the limbal epithelium was unclear. Single cell RNA sequencing (scRNA-seq) suggested that Ace2 involved the proliferation of the stem/eTA cells. Ace2 was reduced following corneal injury. Such reduction enhanced limbal epithelial proliferation and downregulated LCN2, a negative regulator of proliferation in a variety of tissues, via upregulating TGFA and consequently activating epidermal growth factor receptor (EGFR). Inhibition of EGFR or overexpression of LCN2 reversed the increased proliferation in limbal epithelial cells lacking ACE2. Our findings demonstrate that after corneal injury, ACE2 is downregulated, which activates limbal epithelial cell proliferation via a TGFA/EGFR/LCN2 pathway.

From clinical management to personalized medicine: novel therapeutic approaches for ovarian clear cell cancer

Ovarian clear-cell cancer is a rare subtype of epithelial ovarian cancer with unique clinical and biological features. Despite optimal cytoreductive surgery and platinum-based chemotherapy being the standard of care, most patients experience drug resistance and a poor prognosis. Therefore, novel therapeutic approaches have been developed, including immune checkpoint blockade, angiogenesis-targeted therapy, ARID1A synthetic lethal interactions, targeting hepatocyte nuclear factor 1β, and ferroptosis. Refining predictive biomarkers can lead to more personalized medicine, identifying patients who would benefit from chemotherapy, targeted therapy, or immunotherapy. Collaboration between academic research groups is crucial for developing prognostic outcomes and conducting clinical trials to advance treatment for ovarian clear-cell cancer. Immediate progress is essential, and research efforts should prioritize the development of more effective therapeutic strategies to benefit all patients.

Differential molecular pathway expression according to chemotherapeutic response in ovarian clear cell carcinoma

OBJECTIVE

Ovarian clear cell carcinoma (OCCC) is a distinct entity from epithelial ovarian cancer. The prognosis of advanced and recurrent disease is very poor due to resistance to chemotherapeutic agents. Our aim was to explore the molecular alterations among OCCC patients with different chemotherapeutic responses and to obtain insights into potential biomarkers.

METHODS

Twenty-four OCCC patients were included in this study. The patients were divided into two groups based on the relapse time after the first-line platinum-based chemotherapy: the platinum-sensitive group (PS) and the platinum-resistant group (PR). Gene expression profiling was performed using NanoString nCounter PanCancer Pathways Panel.

RESULTS

Gene expression analysis comparing PR vs. PS identified 32 differentially expressed genes: 17 upregulated genes and 15 downregulated genes. Most of these genes are involved in the PI3K, MAPK and Cell Cycle-Apoptosis pathways. In particular, eight genes are involved in two or all three pathways.

CONCLUSION

The dysregulated genes in the PI3K, MAPK, and Cell Cycle-Apoptosis pathways identified and postulated mechanisms could help to probe biomarkers of OCCC platinum sensitivity, providing a research basis for further exploration of targeted therapy.