Postoperative hyperphosphatemia significantly associates with adverse survival in colorectal cancer patients

Statins in the Cause and Prevention of Cancer: Confounding by Indication and Mediation by Rhabdomyolysis and Phosphate Toxicity

Statins are drugs used in cardiovascular pharmacotherapy to decrease hypercholesterolemia and lower the risk of atherosclerosis. Statins also increase the risk of rhabdomyolysis, which is often minimized in comparison with large relative risk reductions of cardiovascular disease reported in clinical trials. By contrast, absolute risk reductions of cardiovascular disease are often clinically insignificant and unreported in statin clinical trials. Additionally, cytotoxic effects of statins inhibit cancer cell proliferation and reduce cancer risk, but other studies found that statins are carcinogenic. Due to an inverse association between incidence of cancer and atherosclerosis, the indication to prescribe statins likely biases the association of statins with cancer prevention. Dietary patterns associated with atherosclerosis and cancer contain inverse amounts of cholesterol and phosphate, an essential mineral that stimulates tumorigenesis. Accordingly, lower cancer risk is associated with high dietary cholesterol intake and increased risk of atherosclerosis. Furthermore, serum is exposed to excessive inorganic phosphate that could increase cancer risk as rhabdomyolysis induced by statins releases phosphate from skeletal muscle breakdown. Increased risk of comorbid conditions associated with statins may share the mediating factor of phosphate toxicity. More research is warranted on statins in the cause and prevention of cancer.

Phosphate and Cellular Senescence

Cellular senescence is one type of permeant arrest of cell growth and one of increasingly recognized contributor to aging and age-associated disease. High phosphate and low Klotho individually and synergistically lead to age-related degeneration in multiple organs. Substantial evidence supports the causality of high phosphate in cellular senescence, and potential contribution to human aging, cancer, cardiovascular, kidney, neurodegenerative, and musculoskeletal diseases. Phosphate can induce cellular senescence both by direct phosphotoxicity, and indirectly through downregulation of Klotho and upregulation of plasminogen activator inhibitor-1. Restriction of dietary phosphate intake and blockage of intestinal absorption of phosphate help suppress cellular senescence. Supplementation of Klotho protein, cellular senescence inhibitor, and removal of senescent cells with senolytic agents are potential novel strategies to attenuate phosphate-induced cellular senescence, retard aging, and ameliorate age-associated, and phosphate-induced disorders.

Can conventional clinical chemistry tests help doctors in the monitoring of oncology patients?

The use of laboratory assays in the diagnostic care of oncology patients can markedly increase the efficacy of cancer treatments. Many cancer-specific biomarker assays have been developed. However, the use of these has some limitations due to their cost. Moreover, not every diagnostic laboratory can perform a complete set of these assays. On the other hand, the smart use of conventional clinical chemistry tests could improve the management of cancer. They could be especially valuable tools in the long-term care of patients with a verified diagnosis. In this review, we discuss the utilization of the conventional clinical chemistry assays for the diagnosis, monitoring and prognosis of various oncological diseases. The use of conventional blood tests to assess the levels of chemical elements, metabolites and proteins (including enzymatic activity measurements) in the care of oncology patients is discussed. We have shown that some clinical chemistry assays could be used in the management of distinct kinds of cancer.

Modulating phosphate consumption, a novel therapeutic approach for the control of cancer cell proliferation and tumorigenesis

Phosphorus, often in the form of inorganic phosphate (Pi), is critical to cellular function on many levels; it is required as an integral component of kinase signaling, in the formation and function of DNA and lipids, and energy metabolism in the form of ATP. Accordingly, crucial aspects of cell mitosis - such as DNA synthesis and ATP energy generation - elevate the cellular requirement for Pi, with rapidly dividing cells consuming increased levels. Mechanisms to sense, respond, acquire, accumulate, and potentially seek Pi have evolved to support highly proliferative cellular states such as injury and malignant transformation. As such, manipulating Pi availability to target rapidly dividing cells presents a novel strategy to reduce or prevent unrestrained cell growth. Currently, limited knowledge exists regarding how modulating Pi consumption by pre-cancerous cells might influence the initiation of aberrant growth during malignant transformation, and if reducing the bioavailability or suppressing Pi consumption by malignant cells could alter tumorigenesis. The concept of targeting Pi-regulated pathways and/or consumption by pre-cancerous or tumor cells represents a novel approach to cancer prevention and control, although current data remains insufficient as to rigorously assess the therapeutic value and physiological relevance of this strategy. With this review, we present a critical evaluation of the paradox of how an element critical to essential cellular functions can, when available in excess, influence and promote a cancer phenotype. Further, we conjecture how Pi manipulation could be utilized as a therapeutic intervention, either systemically or at the cell level, to ultimately suppress or treat cancer initiation and/or progression.

Phosphate toxicity and tumorigenesis

In this article, we briefly summarized evidence that cellular phosphate burden from phosphate toxicity is a pathophysiological determinant of cancer cell growth. Tumor cells express more phosphate cotransporters and store more inorganic phosphate than normal cells, and dysregulated phosphate homeostasis is associated with the genesis of various human tumors. High dietary phosphate consumption causes the growth of lung and skin tumors in experimental animal models. Additional studies show that excessive phosphate burden induces growth-promoting cell signaling, stimulates neovascularization, and is associated with chromosome instability and metastasis. Studies have also shown phosphate is a mitogenic factor that affects various tumor cell growth. Among epidemiological evidence linking phosphate and tumor formation, the Health Professionals Follow-Up Study found that high dietary phosphate levels were independently associated with lethal and high-grade prostate cancer. Further research is needed to determine how excessive dietary phosphate consumption influences initiation and promotion of tumorigenesis, and to elucidate prognostic benefits of reducing phosphate burden to decrease tumor cell growth and delay metastatic progression. The results of such studies could provide the basis for therapeutic modulation of phosphate metabolism for improved patient outcome.

Impact of Perioperative Phosphorus and Glucose Levels on Liver Regeneration and Long-term Outcomes after Major Liver Resection

INTRODUCTION

The impact of phosphorus as well as glycemic alterations on liver regeneration has not been directly examined. We sought to determine the impact of phosphorus and glucose on liver regeneration after major hepatectomy.

METHODS

Early and late liver regeneration index was defined as the relative increase of liver volume (RLV) within 2[(RLV2m-RLVp)/RLVp] and 7 months[(RLV7m-RLVp)/RLVp] following surgery. The association of perioperative metabolic factors, liver regeneration, and outcomes was assessed.

RESULTS

On postoperative day 2, 50 (52.6 %) patients had a low phosphorus level (≤2.4 mg/dl), while 45 (47.4 %) had a normal/high phosphorus level (>2.4 mg/dl). Despite comparable clinicopathologic characteristics (all P > 0.05) and RLV/TLV at surgery (P = 0.84), regeneration index within 2 months was lower in the normal/high phosphorus group (P = 0.01) with these patients having increased risk for postoperative liver failure (P = 0.01). The inhibition of liver regeneration persisted at 7 months (P = 0.007) and was associated with a worse survival (P = 0.02). Preoperative hypoglycemia was associated only with a lower early regeneration index (P = 0.02).

CONCLUSIONS

Normal/high phosphorus was associated with inhibition of early and late liver regeneration, as well as with an increased risk of liver failure and worse long-term outcomes. Immediate preoperative hypoglycemia was associated with a lower early volumetric gain. Metabolic factors may represent early indicators of liver failure that could identify patients at increased risk for worse outcomes.

HLJ1 is a novel biomarker for colorectal carcinoma progression and overall patient survival

The implication of HLJ1, a member of the heat shock protein-40 chaperone family, in colorectal carcinoma (CRC) remains unclear. The aim of this study was to determine the dynamic changes of HLJ1 in CRC both in vitro and in vivo, and the relationship between its level and the survival rate of CRC patients. Both real-time RT-PCR and Western blot were used to detect the expression of HLJ1 in CRC cells, while the distribution of HLJ1 in CRC and its adjacent normal mucosa tissues from CRC patients was determined with immunohistochemistry. Moreover, MTT and in vitro invasive assays were performed to determine the effect of HLJ1 overexpression on cell proliferation and invasion of CRC cells. The results indicated that in highly metastatic CRC cells, the HLJ1 expression was lower than that in lowly metastatic ones, and that the overexpression of HLJ1 significantly inhibited CRC cell proliferation and invasion in vitro. Interestingly, the HLJ1 expression was significantly down-regulated in CRC or lymphatic metastatic tissues from patient, compared to that in the normal mucosa (P<0.05), and the HLJ1 expression was correlated strongly with lymph metastasis, Dukes' stage, and remote metastasis (P<0.05). Most surprisingly, patients with a higher HLJ1 level had a better overall survival rate, compared to that in patients with lower HLJ1 level (P<0.05). Based on all these findings, we conclude that HLJ1 is a strong tumor suppressor for CRC, and thus the down-regulation of the HLJ1 expression may be used as a biomarker to predict clinical outcome of patients with CRC.