Systematic review and meta-analysis of breast cancer risks in relation to 2,3,7,8-tetrachlorodibenzo-p-dioxin and per- and polyfluoroalkyl substances

Per- and polyfluoroalkyl substances and human health outcomes: An umbrella review of systematic reviews with meta-analyses of observational studies

BACKGROUND

Although evidence on the association between per- and polyfluoroalkyl substances (PFASs) and human health outcomes has grown exponentially, specific health outcomes and their potential associations with PFASs have not been conclusively evaluated.

METHODS

We conducted a comprehensive search through the databases of PubMed, Embase, and Web of Science from inception to February 29, 2024, to identify systematic reviews with meta-analyses of observational studies examining the associations between the PFASs and multiple health outcomes. The quality of included studies was evaluated using the A Measurement Tool to Assess Systematic Reviews (AMSTAR) tool, and credibility of evidence was assessed using the Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) criteria. The protocol of this umbrella review (UR) had been registered in PROSPERO (CRD 42023480817).

RESULTS

The UR identified 157 meta-analyses from 29 articles. Using the AMSTAR measurement tool, all articles were categorized as of moderate-to-high quality. Based on the GRADE assessment, significant associations between specific types of PFASs and low birth weight, tetanus vaccine response, and triglyceride levels showed high certainty of evidence. Moreover, moderate certainty of evidence with statistical significance was observed between PFASs and health outcomes including lower BMI z-score in infancy, poor sperm progressive motility, and decreased risk of preterm birth as well as preeclampsia. Fifty-two (33%) associations (e.g., PFASs and gestational hypertension, cardiovascular disease, etc) presented low certainty evidence. Additionally, eighty-five (55%) associations (e.g., PFASs with infertility, lipid metabolism, etc) presented very low certainty evidence.

CONCLUSION

High certainty of evidence supported that certain PFASs were associated with the incidence of low birth weight, low efficiency of the tetanus vaccine, and low triglyceride levels.

Nanomedicine-Based Drug-Targeting in Breast Cancer: Pharmacokinetics, Clinical Progress, and Challenges

Breast cancer (BC) is a malignant neoplasm that begins in the breast tissue. After skin cancer, BC is the second most common type of cancer in women. At the end of 2040, the number of newly diagnosed BC cases is projected to increase by over 40%, reaching approximately 3 million worldwide annually. The hormonal and chemotherapeutic approaches based on conventional formulations have inappropriate therapeutic effects and suboptimal pharmacokinetic responses with nonspecific targeting actions. To overcome such issues, the use of nanomedicines, including liposomes, nanoparticles, micelles, hybrid nanoparticles, etc., has gained wider attention in the treatment of BC. Smaller dimensional nanomedicine (especially 50-200 nm) exhibited improved in vivo effectiveness, such as better tissue penetration and more effective tumor suppression through enhanced retention and permeation, as well as active targeting of the drug. Additionally, nanotechnology, which further extended and developed theranostic nanomedicine by incorporating diagnostic and imaging agents in one platform, has been applied to BC. Furthermore, hybrid and theranostic nanomedicine has also been explored for gene delivery as anticancer therapeutics in BC. Moreover, the nanocarriers' size, shape, surface charge, chemical compositions, and surface area play an important role in the nanocarriers' stability, cellular absorption, cytotoxicity, cellular uptake, and toxicity. Additionally, nanomedicine clinical translation for managing BC remains a slow process. However, a few cases are being used clinically, and their progress with the current challenges is addressed in this Review. Therefore, this Review extensively discusses recent advancements in nanomedicine and its clinical challenges in BC.