Vitamin d and pancreatic cancer-an update

About the associations of vitamin D deficiency and biomarkers of systemic inflammatory response with all-cause and cause-specific mortality in a general population sample of almost 400,000 UK Biobank participants

It is unknown whether the well-known association between vitamin D deficiency and mortality could be explained by the immune system modulating effects of vitamin D, which may protect from a systemic inflammatory response (SIR) to adverse health conditions. This study aims to investigate the interrelationships of vitamin D deficiency, biomarkers of SIR, and mortality. We used multivariate logistic regression with adjustment for 51 covariates to assess the associations of vitamin D deficiency with disadvantageous levels of nine biomarkers of SIR in the UK Biobank cohort. Furthermore, we tested with Cox regression and mediation analysis whether biomarkers of SIR and vitamin D deficiency were independently associated with mortality. We included 397,737 participants aged 37-73 years. Vitamin D deficiency was associated with disadvantageous levels of all blood cell count-based biomarkers, but not with C-reactive protein (CRP)-based biomarkers after adjustment for body weight. Vitamin D deficiency and all biomarkers of SIR were significantly associated with all-cause mortality and mortality from cancer, cardiovascular and respiratory disease. The strength of these associations was unaltered if vitamin D deficiency and biomarkers of SIR were put in the same model. This finding was further supported by the mediation analyses. This study showed that vitamin D deficiency is associated with disadvantageous levels of blood cell count-based but not CRP-based biomarkers of SIR. Vitamin D deficiency and systemic inflammation were independently and strongly associated with mortality. The potential of clinical interventions against both vitamin D deficiency and underlying causes of systemic inflammation should be explored.

Vitamin D Reduces Thyroid Cancer Cells Migration Independently From the Modulation of CCL2 and CXCL8 Chemokines Secretion

BACKGROUND

Vitamin D3 is largely involved in the regulation of calcium homeostasis. More recently, it was demonstrated that vitamin D exerts several beneficial effects against cancer progression through several mechanisms, including the reduction of cancer cells proliferation and migration. CXCL8 and CCL2 are two chemokines secreted by thyroid tumor cells. In the thyroid tumor microenvironment, these chemokines exert several pro-tumorigenic effects including the one to increase the metastatic potential. The aim of the present study was to investigate if vitamin D could modulate both thyroid cancer cell migration and their ability to secrete CCL2 and CXCL8.

METHODS

TPC-1 (RET/PTC rearranged) and 8505C (BRAFV600e mutated) thyroid cancer cell lines were treated with increasing concentrations of 1,25-OH-vitamin D3 (0-1,000 nM). Cell viability was assessed by WST-1 assay, cell migration was evaluated by transwell-migration chamber system, and CCL2 and CXCL8 levels were measured in the cell culture supernatants by ELISA.

RESULTS

Vitamin D did not affect cell viability but reduced, in a dose-dependent and significant manner, thyroid cancer cell migration (ANOVAs p < 0.05 for both TPC-1 and 8505C). Vitamin D differently modulated the secretion of CCL2 and CXCL8, by significantly inhibiting the secretion of CCL2 in both thyroid cancer cell lines and inhibiting the secretion of CXCL8 only in TPC-1 (ANOVAs p < 0.05).

CONCLUSIONS

Vitamin D treatment of thyroid cancer cell lines reduces cell migration independently from the inhibition of the secretion of pro-tumorigenic chemokines. Future studies specifically designed at clarifying the pathways involved in the different inhibitory effects of vitamin D on CCL2 and CXCL8 in thyroid cancer cells appear worthwhile.

Plasma 25-hydroxyvitamin D levels, vitamin D intake, and pancreatic cancer risk or mortality: a meta-analysis

BACKGROUND

The associations between vitamin D status, including plasma 25-hydroxyvitamin D [25(OH)D] levels and vitamin D intake, and pancreatic cancer risk and mortality are inconsistent. The aims of this study are to evaluate the antitumor and therapeutic effects of vitamin D status for pancreatic cancer patients.

METHODS

A literature search for relevant studies was conducted using PubMed and Embase databases. Risk ratio (RR), hazard ratio (HR), and 95% confidence interval (CI) were used as the effect measures. All statistical analyses were performed using Stata software 12.0.

RESULTS

Our results indicated that high plasma 25(OH)D levels were inversely associated with pancreatic cancer mortality without significant heterogeneity (HR=0.81, 95% CI=0.68-0.96). However, high plasma 25(OH)D levels could not reduce pancreatic cancer risk (RR=1.02, 95% CI=0.66-1.57). Moreover, vitamin D intake was also not associated with pancreatic cancer risk (RR=1.11, 95% CI=0.67-1.86).

CONCLUSIONS

Our results indicate that high plasma 25(OH)D levels were significantly associated with improved survival in pancreatic cancer patients. However, there were no significant associations between vitamin D intake or plasma 25(OH)D levels and pancreatic cancer risk.

Vitamins in pancreatic cancer: a review of underlying mechanisms and future applications

Although there is increasing evidence that vitamins influence pancreatic adenocarcinoma biology and carcinogenesis, a comprehensive review is lacking. In this study, we performed a PubMed literature search to review the anticancer mechanisms and the preclinical and clinical studies that support the development of the bioactive vitamins A, C, D, E, and K in pancreatic cancer intervention. Preclinical studies have shown promising results for vitamin A in pancreatic cancer prevention, with clinical trials showing intriguing responses in combination with immunotherapy. For vitamin C, preclinical studies have shown slower tumor growth rates and/or increased survival when used alone or in combination with gemcitabine, with clinical trials with this combination revealing decreased primary tumor sizes and improved performance status. Preclinical studies with vitamin D analogues have shown potent antiproliferative effects and repression of migration and invasion of pancreatic cancer cells, with a clinical trial showing increased time to progression when calciferol was added to docetaxel. For vitamin E, preclinical studies have shown that δ-tocotrienol and γ-tocotrienol inhibited tumor cell growth and survival and augmented gemcitabine activity. Early-phase clinical trials with δ-tocotrienol are ongoing. Vitamin K demonstrates activation of apoptosis and inhibition of cellular growth in pancreatic tumor cells; however, there are no clinical studies available for further evaluation. Although preclinical and clinical studies are encouraging, randomized controlled trials with endpoints based on insights gained from mechanistic and preclinical studies and early-phase clinical trials are required to determine the efficacy of bioactive vitamin interventions in pancreatic cancer.

MART-10, the vitamin D analog, is a potent drug to inhibit anaplastic thyroid cancer cell metastatic potential

The survival rate of anaplastic thyroid cancer (ATC) is still very poor due to its fast growth and high metastatic potential. Currently, no effective treatment is available. The active form of vitamin D3, 1α,25(OH)2D3, has been shown to have a anti-metastatic effect in pre-clinical studies, however induction of hypercalcemia hampered its clinical application. The new class of less-calcemic vitamin D analog, 19-nor-2α-(3-hydroxypropyl)-1α,25-dihydroxyvitamin D3 (MART-10), is much more potent than 1α,25(OH)2D3 to repress cancer growth and metastasis in a variety of cancers. In this study, we demonstrated that both 1α,25(OH)2D3 and MART-10 could effectively inhibit the migration and invasion of ATC cells, 8305C and 8505C, with MART-10 much more potent than 1α,25(OH)2D3. The anti-metastatic effect of 1α,25(OH)2D3 and MART-10 on ATC cells is mediated by reversal of cadherin switch (upregulation of E-cadherin and downregulation of N-cadherin), which led to the attenuation of EMT process, and decrease of F-actin formation. We further showed that the expressions of Slug, the EMT-related transcriptional factor, and MMP-9 were inhibited by 1α,25(OH)2D3 and MART-10 in 8505C cells, but not in 8303C cells. Since metastasis is the important cause of ATC-related death, our results strongly encourage the further in vivo study of MART-10 application against ATC.

PTEN insufficiency modulates ER+ breast cancer cell cycle progression and increases cell growth in vitro and in vivo

Phosphatase and tensin homolog (PTEN), a well-known tumor suppressor gene and frequently mutated or lost in breast cancer, possesses the negative regulation function over the PI3K/Akt/mTOR pathway. PTEN insufficiency has been associated with advanced breast cancer and poor prognosis of breast cancer patients. Recently, target therapies aimed at PI3K/Akt/mTOR pathway to treat breast cancer have got popularity. However, the exact effect of PTEN on breast cancer cells is still not well understood. This study demonstrated that PTEN knockdown in MCF-7 cells strengthened the downstream gene expressions, including p-Akt, p-ERK1/2, p-mTOR, p-p70s6k, and p-GSK3β. PTEN knockdown MCF-7 cells had increased cell growth and Ki-67 expression. Further Western blot demonstrated that p27 was repressed obviously with p21 slightly inhibited and CDK1, 2, 4, 6, cyclin A, and Cdc25C were upregulated in MCF-7 PTEN knockdown cells, leading to the higher growth rate. More importantly, PTEN knockdown MCF-7 cells had higher tumorigenesis and tumor growth in vivo. From our current work, we provided more detailed PTEN-mediated mechanisms to stimulate ER+ breast cancer cell growth. Our result may pave the way for further target therapy development used alone or in combination with other drugs for ER+ breast cancer with PTEN insufficiency.

Diet and nutrition in cancer survivorship and palliative care

The primary goal of palliative cancer care is typically to relieve suffering and improve quality of life. Most approaches to diet in this setting have focused only on eating as many calories as possible to avoid cachexia. However, as the concept of palliative care has evolved to include all aspects of cancer survivorship and not just end of life care, there is an increasing need to thoughtfully consider diet and nutrition approaches that can impact not only quality of life but overall health outcomes and perhaps even positively affect cancer recurrence and progression. In this regard, there has been a recent emphasis in the literature on nutrition and cancer as an important factor in both quality of life and in the pathophysiology of cancer. Hence, the primary purpose of this paper is to review the current data on diet and nutrition as it pertains to a wide range of cancer patients in the palliative care setting.