Lower Serum Sodium Levels Are Associated with the Therapeutic Effect of Sorafenib on Hepatocellular Carcinoma

Effects of Reduced Extracellular Sodium Concentrations on Cisplatin Treatment in Human Tumor Cells: The Role of Autophagy

Hyponatremia is the prevalent electrolyte imbalance in cancer patients, and it is associated with a worse outcome. Notably, emerging clinical evidence suggests that hyponatremia adversely influences the response to anticancer treatments. Therefore, this study aims to investigate how reduced extracellular [Na+] affects the responsiveness of different cancer cell lines (from human colon adenocarcinoma, neuroblastoma, and small cell lung cancer) to cisplatin and the underlying potential mechanisms. Cisplatin dose-response curves revealed higher IC50 in low [Na+] than normal [Na+]. Accordingly, cisplatin treatment was less effective in counteracting the proliferation and migration of tumor cells when cultured in low [Na+], as demonstrated by colony formation and invasion assays. In addition, the expression analysis of proteins involved in autophagosome-lysosome formation and the visualization of lysosomal areas by electron microscopy revealed that one of the main mechanisms involved in chemoresistance to cisplatin is the promotion of autophagy. In conclusion, our data first demonstrate that the antitumoral effect of cisplatin is markedly reduced in low [Na+] and that autophagy is an important mechanism of drug escape. This study indicates the role of hyponatremia in cisplatin chemoresistance and reinforces the recommendation to correct this electrolyte alteration in cancer patients.

Hyponatremia and Cancer: From Bedside to Benchside

Hyponatremia is the most common electrolyte disorder encountered in hospitalized patients. This applies also to cancer patients. Multiple causes can lead to hyponatremia, but most frequently this electrolyte disorder is due to the syndrome of inappropriate antidiuresis. In cancer patients, this syndrome is mostly secondary to ectopic secretion of arginine vasopressin by tumoral cells. In addition, several chemotherapeutic drugs induce the release of arginine vasopressin by the hypothalamus. There is evidence that hyponatremia is associated to a more negative outcome in several pathologies, including cancer. Many studies have demonstrated that in different cancer types, both progression-free survival and overall survival are negatively affected by hyponatremia, whereas the correction of serum [Na⁺] has a positive effect on patient outcome. In vitro studies have shown that cells grown in low [Na⁺] have a greater proliferation rate and motility, due to a dysregulation in intracellular signalling pathways. Noteworthy, vasopressin receptors antagonists, which were approved more than a decade ago for the treatment of euvolemic and hypervolemic hyponatremia, have shown unexpected antiproliferative effects. Because of this property, vaptans were also approved for the treatment of polycystic kidney disease. In vitro evidence indicated that this family of drugs effectively counteracts proliferation and invasivity of cancer cells, thus possibly opening a new scenario among the pharmacological strategies to treat cancer.

Effects of Short-Term Human Albumin Infusion for the Prevention and Treatment of Hyponatremia in Patients with Liver Cirrhosis

Background: Human albumin (HA) infusion is potentially effective for the management of hyponatremia in liver cirrhosis, but the current evidence is very limited. Methods: In this retrospective study, 2414 cirrhotic patients who were consecutively admitted to our hospital between January 2010 and June 2014 were included in the Hospitalization outcome cohort, and 339 cirrhotic patients without malignancy who were consecutively admitted to our department between December 2014 and April 2021 were included in the Long-term outcome cohort. The development and improvement of hyponatremia were compared between patients who received HA infusion during hospitalizations and did not. Logistic and Cox regression analyses were performed to evaluate the association of development and improvement of hyponatremia during hospitalizations with the outcomes. Odds ratios (ORs) and hazard ratios (HRs) were calculated. Results: In the two cohorts, HA infusion significantly decreased the incidence of hyponatremia and increased the rate of improvement of hyponatremia in cirrhotic patients during hospitalizations. In the Hospitalization outcome cohort, the development of hyponatremia during hospitalizations was significantly associated with increased in-hospital mortality (OR = 2.493, p < 0.001), and the improvement of hyponatremia during hospitalizations was significantly associated with decreased in-hospital mortality (OR = 0.599, p = 0.014). In the Long-term outcome cohort, the development of hyponatremia during hospitalizations was significantly associated with decreased long-term survival (HR = 0.400, p < 0.001), and the improvement of hyponatremia during hospitalizations was not significantly associated with long-term survival (HR = 1.085, p = 0.813). Conclusions: HA infusion can effectively prevent the development of hyponatremia and improve hyponatremia in cirrhotic patients during hospitalizations, which may influence the patients’ outcomes.

Clinical laboratory tests associated with survival in patients with metastatic renal cell carcinoma: A Laboratory Wide Association Study (LWAS)

BACKGROUND

Prognostic models for patients with metastatic renal cell carcinoma (mRCC) include select laboratory values. These models have important limitations, including reliance on a limited array of laboratory tests, and use of dichotomous ("high-low") cutoffs. We applied a Laboratory-Wide Association Study (LWAS) framework to systematically evaluate common clinical laboratory results associated with survival for patients diagnosed with mRCC.

METHODS

We used laboratory data for 3,385 patients diagnosed with mRCC from 2002 to 2017. We developed a LWAS framework, to examine the association with 53 common clinical laboratory tests results (641,712 measurements) and overall survival. We employed false-discovery rate to test the association of multiple laboratory tests with survival, and validated these results using 3 separate cohorts to generate a standardized hazard ratio (sHR), reported for a 1 standard deviation unit change in each laboratory test.

RESULTS

The LWAS approach confirmed the association of laboratory values currently used in prognostic models with survival, including calcium (HR 1.35, 95%CI 1.24-1.48), leukocyte count (HR 1.40, 95%CI 1.30-1.51), platelet count (HR 1.36, 95%CI 1.27-1.51), and hemoglobin (HR 0.79, 95%CI 0.72-0.86). Use of these tests as continuous variables improved model performance. LWAS also identified acute phase reactants associated with survival not typically included in prognostic models, including serum albumin (HR 0.66, 95%CI 0.61-0.72), ferritin (HR 1.25, 95%CI 1.08-1.45), alkaline phosphatase (HR 1.31, 95%CI 1.23-1.40), and C-reactive protein (HR 1.70, 95%CI 1.14-2.53).

CONCLUSIONS

Routinely measured laboratory tests can refine current prognostic models, facilitate comparisons across clinical trial cohorts, and match patients with specific systemic therapies.