Cellular Oxidative Stress in Pediatric Leukemia and Lymphoma Patients Undergoing Treatment Is Associated with Protein Consumption.

Over and under nutrition are associated with worse outcomes for children with leukemia and lymphoma; however, the molecular basis for this clinical observation is not well understood. Many chemotherapeutics used for leukemia treatment are known to generate oxidative stress in vitro; therefore, we evaluated redox status and diet in pediatric leukemia patients during therapy in order to ascertain relationships between nutrition and oxidative stress. Dietary intake and redox measures in peripheral blood mononuclear cells from 32 pediatric leukemia and lymphoma patients were collected over six months during treatment. Baseline measures when patients were off chemotherapy and subsequent assessments were collected after one, two and six months. Oxidative stress increased over time in all patients, consistent with chemotherapy-induced redox effects. Older and younger children showed significantly different baseline levels of reactive oxygen species, which increased over time in all age ranges. Diet was assessed at points proximal to oxidative stress measurements and revealed a novel association with consumption of animal protein, vegetable protein, and total protein intake. Our findings demonstrate that chemotherapy increases oxidative stress in pediatric leukemia patients, and raises the possibility that dietary protein or altered protein metabolism could contribute to clinical outcomes.

Low-Protein Diet Induces IRE1α-Dependent Anticancer Immunosurveillance.

Dietary restriction (DR) was shown to impact on tumor growth with very variable effects depending on the cancer type. However, how DR limits cancer progression remains largely unknown. Here, we demonstrate that feeding mice a low-protein (Low PROT) isocaloric diet but not a low-carbohydrate (Low CHO) diet reduced tumor growth in three independent mouse cancer models. Surprisingly, this effect relies on anticancer immunosurveillance, as depleting CD8+ T cells, antigen-presenting cells (APCs), or using immunodeficient mice prevented the beneficial effect of the diet. Mechanistically, we established that a Low PROT diet induces the unfolded protein response (UPR) in tumor cells through the activation of IRE1α and RIG1 signaling, thereby resulting in cytokine production and mounting an efficient anticancer immune response. Collectively, our data suggest that a Low PROT diet induces an IRE1α-dependent UPR in cancer cells, enhancing a CD8-mediated T cell response against tumors.

Modulating the therapeutic response of tumours to dietary serine and glycine starvation.

The non-essential amino acids serine and glycine are used in multiple anabolic processes that support cancer cell growth and proliferation (reviewed in ref. 1). While some cancer cells upregulate de novo serine synthesis, many others rely on exogenous serine for optimal growth. Restriction of dietary serine and glycine can reduce tumour growth in xenograft and allograft models. Here we show that this observation translates into more clinically relevant autochthonous tumours in genetically engineered mouse models of intestinal cancer (driven by Apc inactivation) or lymphoma (driven by Myc activation). The increased survival following dietary restriction of serine and glycine in these models was further improved by antagonizing the anti-oxidant response. Disruption of mitochondrial oxidative phosphorylation (using biguanides) led to a complex response that could improve or impede the anti-tumour effect of serine and glycine starvation. Notably, Kras-driven mouse models of pancreatic and intestinal cancers were less responsive to depletion of serine and glycine, reflecting an ability of activated Kras to increase the expression of enzymes that are part of the serine synthesis pathway and thus promote de novo serine synthesis.

Butyrate production from high-fiber diet protects against lymphoma tumor.

Gut microbiota and dietary fiber are critical for protecting body from obesity, diabetes and cancer. Butyrate, produced in the gut by bacterial fermentation of dietary fibers, is demonstrated to be protective against the development of colorectal cancer as a histone deacetylase (HDAC) inhibitor. We report that high-fiber diet and butyrate significantly inhibited the growth lymphoma tumors. Butyrate induced apoptosis of lymphoma tumor cells and significantly up-regulated histone 3 acetylation (H3ac) level and target genes such as Fas, P21, P27. Our results unravel an instrumental role of fiber diet and their metabolites on lymphoma tumor and demonstrate an intervention potential on the prevention and therapy of lymphoma.

Questioning the role of a neutropenic diet following hematopoetic stem cell transplantation.

The use of a neutropenic diet (ND) after hematopoietic stem cell transplantation (HSCT) was instituted more than 30 years ago as a means of preventing infection from organisms colonizing the gastrointestinal tract. Evidence supporting this practice is lacking, however, and the actual efficacy of the ND remains unknown. Institutional policy at Northwestern Memorial Hospital discontinued the use of ND in 2006. We conducted a retrospective study of 726 consecutive HSCT recipients, 363 who received an ND and 363 who received a general hospital diet, to determine the incidence of microbiologically confirmed infections during and after transplantation. Our findings indicate a higher rate of infections in the HSCT recipients who received an ND.

'Iron-saturated' lactoferrin is a potent natural adjuvant for augmenting cancer chemotherapy.

Bovine lactoferrin (bLf), an iron-containing natural defence protein found in bodily secretions, has been reported to inhibit carcinogenesis and the growth of tumours. Here, we investigated whether natural bLf and iron-saturated forms of bLf differ in their ability to augment cancer chemotherapy. bLf was supplemented into the diet of C57BL/6 mice that were subsequently challenged subcutaneously with tumour cells, and treated by chemotherapy. Chemotherapy eradicated large (0.6 cm diameter) EL-4 lymphomas in mice that had been fed iron-saturated bLf (here designated Lf(+)) for 6 weeks prior to chemotherapy, but surprisingly not in mice that were fed lesser iron-saturated forms of bLf, including apo-bLf (4% iron saturated), natural bLf (approximately 15% iron saturated) and 50% iron-saturated bLf. Lf(+)-fed mice bearing either EL-4, Lewis lung carcinoma or B16 melanoma tumours completely rejected their tumours within 3 weeks following a single injection of either paclitaxel, doxorubicin, epirubicin or fluorouracil, whereas mice fed the control diet were resistant to chemotherapy. Lf(+) had to be fed to mice for more than 2 weeks prior to chemotherapy to be wholly effective in eradicating tumours from all mice, suggesting that it acts as a competence factor. It significantly reduced tumour vascularity and blood flow, and increased antitumour cytotoxicity, tumour apoptosis and the infiltration of tumours by leukocytes. Lf(+) bound to the intestinal epithelium and was preferentially taken up within Peyer's patches. It increased the production of Th1 and Th2 cytokines within the intestine and tumour, including TNF, IFN-gamma, as well as nitric oxide that have been reported to sensitize tumours to chemotherapy. Importantly, it restored both red and white peripheral blood cell numbers depleted by chemotherapy, potentially fortifying the mice against cancer. In summary, bLf is a potent natural adjuvant and fortifying agent for augmenting cancer chemotherapy, but needs to be saturated with iron to be effective.

Multifocal small bowel lymphoma and latent celiac sprue.

Malignant small intestinal lymphoma may complicate or antedate clinical recognition of celiac sprue, a disorder becoming increasingly diagnosed as a subclinical or occult disease. A 73-yr-old woman with previously resected jejunoileal lymphoma and normal proximal small bowel biopsy specimens was given a high-gluten diet containing 40 g of added gluten daily for 4 wk. This caused small intestinal biopsy abnormalities typical of celiac sprue; the abnormalities resolved 6 wk later with a gluten-free diet. This indicates that latent celiac sprue may be present in some patients with lymphoma and suggests that the association of celiac sprue and lymphoma may be more frequent than is currently appreciated.