Ovarian tissue cryopreservation and transplantation in menopause: new perspective of therapy in postmenopausal women and the importance of ethical and legal frameworks

Menopausal transition entails a progressive decrease in hormone production by the ovaries that lead to important physical and psychological changes that could significantly affect quality of life. Hormone replacement therapy (HRT) administered from the onset of menopausal symptoms usually improves quality of life and life expectancy. Nevertheless, it is not risk-free. Ovarian tissue cryopreservation (OTC) has been investigated as a potential new strategy for delaying menopause and/or to avoid HRT. This review analyzes the critical points of HRT to assess whether OTC and subsequent reimplantation can affect postmenopausal management. We assessed available randomized clinical trials in PubMed, Cochrane Library, ISI web of science, and Scopus from August 2021 to November 2022, including studies and trials evaluating the efficacy of OTC in both cancer and menopausal patients, the efficacy of freezing techniques and the possible clinical scenarios that OTC can open, even from the standpoint of legal and ethical issues arising as such innovative techniques become mainstream. Lower duration of the graft and efficacy on estrogen secretions at a physiological and safer concentration of estrogen than conventional HRT based on hormonal supplements. OTC can reportedly trigger estrogen secretions at a lower and safer physiological concentration than conventional HRT. OTC and subsequent reimplantation remain a valid fertility-sparing approach in patients undergoing gonadotoxic treatments. Further studies are needed to better evaluate its safety and efficacy within postmenopausal therapy management and in order to lay out widely shared and evidence-based guidelines and best practices and perform such novel and innovative techniques in a legally and ethically safe fashion, in the best interest of patients and healthcare professionals.

DCLK1, a Putative Stem Cell Marker in Human Cholangiocarcinoma

BACKGROUND AND AIMS

Cholangiocarcinoma (CCA) is a very aggressive cancer showing the presence of high cancer stem cells (CSCs). Doublecortin-like kinase1 (DCLK1) has been demonstrated as a CSC marker in different gastroenterological solid tumors. Our aim was to evaluate in vitro the expression and the biological function of DCLK1 in intrahepatic CCA (iCCA) and perihilar CCA (pCCA).

APPROACH AND RESULTS

Specimens surgically resected of human CCA were enzymatically digested, submitted to immunosorting for specific CSC markers (LGR5 [leucine-rich repeat-containing G protein-coupled receptor], CD [clusters of differentiation] 90, EpCAM [epithelial cell adhesion molecule], CD133, and CD13), and primary cell cultures were prepared. DCLK1 expression was analyzed in CCA cell cultures by real-time quantitative PCR, western blot, and immunofluorescence. Functional studies have been performed by evaluating the effects of selective DCLK1 inhibitor (LRRK2-IN-1) on cell proliferation (MTS [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium] assay, cell population doubling time), apoptosis, and colony formation capacity. DCLK1 was investigated in situ by immunohistochemistry and real-time quantitative PCR. DCLK1 serum concentration was analyzed by enzyme-linked immunosorbent assay. We describe DCLK1 in CCA with an increased gene and protein DCLK1 expression in pCCA^LGR5+ and in iCCA^CD133+ cells compared with unsorted cells. LRRK2-IN-1 showed an anti-proliferative effect in a dose-dependent manner. LRRK2-IN-1 markedly impaired cell proliferation, induced apoptosis, and decreased colony formation capacity and colony size in both iCCA and pCCA compared with the untreated cells. In situ analysis confirmed that DCLK1 is present only in tumors, and not in healthy tissue. Interestingly, DCLK1 was detected in the human serum samples of patients with iCCA (high), pCCA (high), HCC (low), and cirrhosis (low), but it was almost undetectable in healthy controls.

CONCLUSIONS

DCLK1 characterizes a specific CSC subpopulation of iCCA^CD133+ and pCCA^LGR5+ , and its inhibition exerts anti-neoplastic effects in primary CCA cell cultures. Human DCLK1 serum might represent a serum biomarker for the early CCA diagnosis.

Analysis of phosphate kinetics in hemofiltration and hemodiafiltration: formulation of an efficiency index

The kinetics of phosphate (P) during a treatment of hemofiltration or hemodiafiltration follows a simple exponential law, and P in 90 min reaches a stationary level that remains constant until the end of the treatment. The theoretical compartmental model cannot be estimated by a dialytic treatment, but a simpler diffusive model may be considered. Once the stationary level is reached, the net flux of P from the inaccessible compartments to the accessible compartment may be estimated via the parameters obtained in the exponential model. Hemodiafiltration seems more efficient than hemofiltration in determining P clearance. Thus an efficiency index that accounts for the period in which P is eliminated from the accessible compartment has been formulated.