Characterization of candidate factors associated with the metastasis and progression of high-grade serous ovarian cancer

Olaparib and niraparib as maintenance therapy in patients with newly diagnosed and platinum-sensitive recurrent ovarian cancer: A single-center study in China

BACKGROUND

Poly adenosine-diphosphate-ribose polymerase (PARP) inhibitors (PARPi) have been approved to act as first-line maintenance (FL-M) therapy and as platinum-sensitive recurrent maintenance (PSR-M) therapy for ovarian cancer in China for >5 years. Herein, we have analyzed the clinical-application characteristics of olaparib and niraparib in ovarian cancer-maintenance therapy in a real-world setting to strengthen our understanding and promote their rational usage.

METHODS

A retrospective chart review identified patients with newly diagnosed or platinum-sensitive recurrent ovarian cancer, who received olaparib or niraparib as maintenance therapy at Sichuan Cancer Hospital between August 1, 2018, and December 31, 2021. Patient medical records were reviewed. We grouped and analyzed patients based on the type of PARPi they used (the olaparib group and the niraparib group) and the line of PARPi maintenance therapy (the FL-M setting and the PSR-M setting). The primary endpoint was the 24-month progression-free survival (PFS) rate.

RESULTS

In total, 131 patients (olaparib: n = 67, 51.1%; niraparib: n = 64, 48.9%) were enrolled. Breast cancer susceptibility genes (BRCA) mutations (BRCAm) were significantly less common in the niraparib group than in the olaparib group [9.4% (6/64) vs. 62.7% (42/67), P <0.001], especially in the FL-M setting [10.4% (5/48) vs. 91.4% (32/35), P <0.001]. The 24-month PFS rates in the FL-M and PSR-M settings were 60.4% and 45.7%, respectively. In patients with BRCAm, the 24-month PFS rates in the FL-M and PSR-M settings were 62.2% and 72.7%, respectively.

CONCLUSIONS

Olaparib and niraparib were effective in patients with ovarian cancer without any new safety signals except for skin pigmentation. In patients with BRCAm, the 24-month PFS of the PARPi used in the PSR-M setting was even higher than that used in the FL-M setting.

Homeobox Protein BarH-like 1 Promotes Gastric Cancer Progression by Activating Coiled-Coil Domain-Containing Protein 178

BACKGROUND

Coiled-coil domain-containing protein 178 (CCDC178) has been revealed to exert metastasis-promoting properties in hepatocellular carcinoma, whereas its function in gastric cancer (GC) has not been fully understood.

AIMS

We evaluated its role in GC and the molecular mechanism.

METHODS

The differentially expressed genes in datasets related to GC metastasis were intersected with survival-related genes in GC, followed by prognostic significance prediction. Loss- and gain-of-function assays were conducted to examine the involvement of CCDC178, Homeobox protein BarH-like 1 (BARX1), and the extracellular signal-regulated kinase (ERK) pathway in GC cell malignant phenotype and the polarization of tumor-associated macrophages (TAM). The corresponding functions were verified in the in vivo animal experiment.

RESULTS

High CCDC178 expression predicted a poor prognosis for GC patients, and CCDC178 correlated significantly with macrophage infiltration in GC tissues. CCDC178 activated the ERK pathway in GC. Silencing of CCDC178 reduced the colony formation, migratory and invasive potential of GC cells, and the M2-like polarization of TAM, which was reversed by TBHQ (an ERK activator). BARX1 bound to the promoter region of CCDC178, thus inducing its transcriptional level. Silencing of BARX1 suppressed the M2-type polarization of TAM in vitro and in vivo, and CCDC178 mitigated the repressing role of BARX1 knockdown.

CONCLUSIONS

BARX1 activates the transcription of CCDC178 to induce the ERK pathway, thereby supporting macrophage recruitment and M2-like polarization in GC.

Recent advances in acid sensing by G protein coupled receptors

Changes in extracellular proton concentrations occur in a variety of tissues over a range of timescales under physiological conditions and also accompany virtually all pathologies, notably cancers, stroke, inflammation and trauma. Proton-activated, G protein coupled receptors are already partially active at physiological extracellular proton concentrations and their activity increases with rising proton concentrations. Their ability to monitor and report changes in extracellular proton concentrations and hence extracellular pH appears to be involved in a variety of processes, and it is likely to mirror and in some cases promote disease progression. Unsurprisingly, therefore, these pH-sensing receptors (pHR) receive increasing attention from researchers working in an expanding range of research areas, from cellular neurophysiology to systemic inflammatory processes. This review is looking at progress made in the field of pHRs over the past few years and also highlights outstanding issues.

Molecular Regulation and Oncogenic Functions of TSPAN8

Tetraspanins, a superfamily of small integral membrane proteins, are characterized by four transmembrane domains and conserved protein motifs that are configured into a unique molecular topology and structure in the plasma membrane. They act as key organizers of the plasma membrane, orchestrating the formation of specialized microdomains called "tetraspanin-enriched microdomains (TEMs)" or "tetraspanin nanodomains" that are essential for mediating diverse biological processes. TSPAN8 is one of the earliest identified tetraspanin members. It is known to interact with a wide range of molecular partners in different cellular contexts and regulate diverse molecular and cellular events at the plasma membrane, including cell adhesion, migration, invasion, signal transduction, and exosome biogenesis. The functions of cell-surface TSPAN8 are governed by ER targeting, modifications at the Golgi apparatus and dynamic trafficking. Intriguingly, limited evidence shows that TSPAN8 can translocate to the nucleus to act as a transcriptional regulator. The transcription of TSPAN8 is tightly regulated and restricted to defined cell lineages, where it can serve as a molecular marker of stem/progenitor cells in certain normal tissues as well as tumors. Importantly, the oncogenic roles of TSPAN8 in tumor development and cancer metastasis have gained prominence in recent decades. Here, we comprehensively review the current knowledge on the molecular characteristics and regulatory mechanisms defining TSPAN8 functions, and discuss the potential and significance of TSPAN8 as a biomarker and therapeutic target across various epithelial cancers.

Blood Plasma Small Non-Coding RNAs as Diagnostic Molecules for the Progesterone-Receptor-Negative Phenotype of Serous Ovarian Tumors

The expression level of the progesterone receptor (PGR) plays a crucial role in determining the biological characteristics of serous ovarian carcinoma. Low PGR expression is associated with chemoresistance and a poorer outcome. In this study, our objective was to explore the relationship between tumor progesterone receptor levels and RNA profiles (miRNAs, piwiRNAs, and mRNAs) to understand their biological characteristics and behavior. To achieve this, we employed next-generation sequencing of small non-coding RNAs, quantitative RT-PCR, and immunohistochemistry to analyze both FFPE and frozen tumor samples, as well as blood plasma from patients with benign cystadenoma (BSC), serous borderline tumor (SBT), low-grade serous ovarian carcinoma (LGSOC), and high-grade serous ovarian carcinoma (HGSOC). Our findings revealed significant upregulation of MMP7 and MUC16, along with downregulation of PGR, in LGSOC and HGSOC compared to BSC. We observed significant correlations of PGR expression levels in tumor tissue with the contents of miR-199a-5p, miR-214-3p, miR-424-3p, miR-424-5p, and miR-125b-5p, which potentially target MUC16, MMP7, and MMP9, as well as with the tissue content of miR-16-5p, miR-17-5p, miR-20a-5p, and miR-93-5p, which are associated with the epithelial-mesenchymal transition (EMT) of cells. The levels of EMT-associated miRNAs were significantly correlated with the content of hsa_piR_022437, hsa_piR_009295, hsa_piR_020813, hsa_piR_004307, and hsa_piR_019914 in tumor tissues. We developed two optimal logistic regression models using the quantitation of hsa_piR_020813, miR-16-5p, and hsa_piR_022437 or hsa_piR_004307, hsa_piR_019914, and miR-93-5p in the tumor tissue, which exhibited a significant ability to diagnose the PGR-negative tumor phenotype with 93% sensitivity. Of particular interest, the blood plasma levels of miR-16-5p and hsa_piR_022437 could be used to diagnose the PGR-negative tumor phenotype with 86% sensitivity even before surgery and chemotherapy. This knowledge can help in choosing the most effective treatment strategy for this aggressive type of ovarian cancer, such as neoadjuvant chemotherapy followed by cytoreduction in combination with hyperthermic intraperitoneal chemotherapy and targeted therapy, thus enhancing the treatment's effectiveness and the patient's longevity.