Metabolism and pharmacokinetics of radium-223 in prostate cancer

Adverse events in patients with castration-resistant prostate cancer treated with ra-223: a retrospective pharmacovigilance study

BACKGROUND

Radium-223 (Ra-223) received U.S. Food and Drug Administration (FDA) approval for treating castration-resistant prostate cancer with symptomatic bone metastases, excluding visceral metastases. Despite this, the safety profile of Ra-223 in large-scale, population-based use still needs to be explored.

RESEARCH DESIGN AND METHODS

This research assesses the side effects of Ra-223 by analyzing reports of adverse events (AEs) from the FDA's Adverse Event Reporting System (FAERS) database. Four sequential analysis strategies were employed to assess the significance of these AEs.

RESULTS

In total, 4,228 Ra-223-related AE reports were identified in the FAERS database. These Ra-223-induced AEs were observed in 26 target system organ classes (SOCs). 124 Ra-223-induced AEs were detected in 26 SOCs, predominantly affecting the blood and lymphatic systems. Other notable AEs included diarrhea, nausea, asthenia, fatigue, malaise, and decreased appetite, some of which were not previously documented in product specifications. The median time to onset of AEs was 56 days (Interquartile Range 26-103 days), with the majority of AEs occurring within the first three months after Ra-223 administration.

CONCLUSIONS

Our findings align with clinical observations and suggest potential new and unexpected AEs related to Ra-223, underscoring the need for prospective clinical studies to confirm these results and clarify their relationships. These insights provide valuable evidence for further safety studies and the rational use of Ra-223.

lncRNA ZFAS1 Is Involved in the Proliferation, Invasion and Metastasis of Prostate Cancer Cells Through Competitively Binding to miR-135a-5p

Background

Prostate cancer (PCa) is a common malignant tumor in men. lncRNA ZFAS1 plays a carcinogenic role in many types of cancer; however, its potential role in PCa remains unclear. The current study aimed to determine the expression and function of ZFAS1 in PC.

Methods

The ZFAS1 expression in PC tissues and cells was determined by quantitative polymerase chain reaction (qPCR). SiZFAS1, miR-135a-5p mimic and miR-135a-5p inhibitor were transfected into PCa cells. The direct target of ZFAS1 was predicted by Starbase and verified by dual-luciferase reporter. Cell viability, proliferation, apoptosis, migration and invasion of the PCa cells were determined by cell counting kit-8, clone formation assay, flow cytometer, scratch and Transwell assay, respectively. The expression levels of related proteins and mRNAs were determined by Western blotting and qPCR.

Results

ZFAS1 expression was up-regulated in PCa cells and tissues. ZFAS1 could competitively bind to miR-135a-5p in PCa cells, and down-regulation of ZFAS1 inhibited cell viability, proliferation, migration, invasion of PCa cells and the occurrence of epithelial-mesenchymal transformation (EMT) and promoted apoptosis of PCa cells and increased the miR-135a-5p expression. Moreover, the function of miR-135a-5p mimic in PCa cells was consistent with ZFAS1 knockdown, while the function of miR-135a-5p inhibitor was opposite to that of miR-135a-5p mimic in PCa cells. The results showed that knocking down ZFAS1 could attenuate the effects of miR-135a-5p inhibitor on cell proliferation, invasion and EMT of PCa cells.

Conclusion

Knocking down ZFAS1 could inhibit the proliferation, invasion and metastasis of PCa cells through regulating miR-135a-5p expression.

Factors affecting (223)Ra therapy: clinical experience after 532 cycles from a single institution

PURPOSE

The aim of this study was to identify baseline features that predict outcome in (223)Ra therapy.

METHODS

We retrospectively reviewed 110 patients with metastatic castration-resistant prostate cancer treated with (223)Ra. End points were overall survival (OS), progression-free survival (PFS), bone event-free survival (BeFS), and bone marrow failure (BMF). The following parameters were evaluated prior to the first (223)Ra cycle: serum levels of hemoglobin (Hb), prostate-specific antigen (PSA), alkaline phosphatase (ALP), Eastern Cooperative Oncology Group (ECOG) status, pain score, use of chemotherapy, and external beam radiation therapy (EBRT). During/after (223)Ra we evaluated: the total number of radium cycles (RaTot), the PSA doubling time (PSADT), and the use of chemotherapy, EBRT, abiraterone, and enzalutamide.

RESULTS

A significant reduction of ALP (p < 0.001) and pain score (p = 0.041) occurred throughout the (223) Ra cycles. The risk of progression was associated with declining ECOG status [hazard ratio (HR) = 3.79; p < 0.001] and decrease in PSADT (HR = 8.22; p < 0.001). RaTot, ALP, initial ECOG status, initial pain score, and use of abiraterone were associated with OS (p ≤ 0.008), PFS (p ≤ 0.003), and BeFS (p ≤ 0.020). RaTot, ALP, initial ECOG status, and initial pain score were significantly associated with BMF (p ≤ 0.001) as well as Hb (p < 0.001) and EBRT (p = 0.009). On multivariable analysis, only RaTot and abiraterone remained significantly associated with OS (p < 0.001; p = 0.033, respectively), PFS (p < 0.001; p = 0.041, respectively), and BeFS (p < 0.001; p = 0.019, respectively). Additionally, RaTot (p = 0.027) and EBRT (p = 0.013) remained significantly associated with BMF.

CONCLUSION

Concomitant use of abiraterone and (223)Ra seems to have a beneficial effect, while the EBRT may increase the risk of BMF.