Modulation of cell cycle kinetics in human cancer with total parenteral nutrition

Targeting Cellular Metabolism Modulates Head and Neck Oncogenesis

Considering the great energy and biomass demand for cell survival, cancer cells exhibit unique metabolic signatures compared to normal cells. Head and neck squamous cell carcinoma (HNSCC) is one of the most prevalent neoplasms worldwide. Recent findings have shown that environmental challenges, as well as intrinsic metabolic manipulations, could modulate HNSCC experimentally and serve as clinic prognostic indicators, suggesting that a better understanding of dynamic metabolic changes during HNSCC development could be of great benefit for developing adjuvant anti-cancer schemes other than conventional therapies. However, the following questions are still poorly understood: (i) how does metabolic reprogramming occur during HNSCC development? (ii) how does the tumorous milieu contribute to HNSCC tumourigenesis? and (iii) at the molecular level, how do various metabolic cues interact with each other to control the oncogenicity and therapeutic sensitivity of HNSCC? In this review article, the regulatory roles of different metabolic pathways in HNSCC and its microenvironment in controlling the malignancy are therefore discussed in the hope of providing a systemic overview regarding what we knew and how cancer metabolism could be translated for the development of anti-cancer therapeutic reagents.

Does Parenteral Nutrition Increase Tumor Growth? A Review

Total parenteral nutrition (TPN) is a supportive therapy commonly used in clinical oncology, in spite of its possible interference on tumor growth. In fact, studies performed on animals have demonstrated that TPN increases tumor growth and that load and quality of amino acids are probably the main factors involved. In contrast, some authors obtained a decrease in tumor growth using a special amino acids mixture or a TPN formula rich in lipids. However, data collected on animals are not transferable to humans owing to the large difference between tumor-host weight ratio and tumor doubling time. Analy sis of the studies on effect of TPN on tumor growth in humans has not demonstrated a bad effect, but the results reported in the literature are limited by the small number of patients, the lack of a sure and reproducible method to analyze tumor growth, and some methodologic defects. In conclusion, it is not evident that TPN is dangerous for cancer patients. However, it may be possible in the future to employ different formulas to improve the host nutritional status and inhibit tumor growth.

Total Parenteral Nutrition and Tumor Growth in Malnourished Patients with Gastric Cancer

Aims and Background

Evidence that total parenteral nutrition (TPN) can stimulate tumor growth in humans is scanty and contradictory. The purpose of this study was to evaluate the impact of TPN on tumor cell proliferation in malnourished patients receiving preoperative TPN.

Methods

We evaluated variations in the S-phase cell fraction, defined as 3H-thymidine labeling index (TLI), before and after 10 days of TPN or non-administration of nutritional support in 19 malnourished patients (weight loss, ≥ 10%) with gastric cancer. TLI was determined on endoscopic biopsies at the time of diagnosis, and subsequently on the operative specimen or through intraoperative sampling.

Results

At diagnosis, a higher median TLI value was observed in the control than in the TPN group. Administration of TPN enhanced tumor cell proliferation in 50% of patients; however, at surgery there was no difference in the median TLI value of the two groups.

Conclusions

The TPN regimen seems to be associated with increased tumor cell proliferation, even though this stimulating effect was moderate and at surgery the TLIS of TPN patients and controls were not different. Although the potential stimulation probably has little consequence for patients receiving short-term preoperative nutrition, it may call for further investigation in cancer patients undergoing long-term home TPN.

Relationship between Nutritional Status and Tumor Growth in Humans

Aims and background

There is considerable evidence from studies on tumor-bearing animals that nutritional support aimed at maintaining a good nutritional status can indeed promote tumor growth. Experience in humans, however, is scanty and controversial, this issue never having been extensively investigated. The purpose of this study was to analyze whether there exists a relationship between nutritional status and tumor growth in patients with non-Hodgkin's lymphoma. The hypothesis behind it was that if it is true than an abundant availability of substrates promotes tumoral growth, then the better the nutritional status the higher the tumor cell proliferation.

Methods

Two hundred and forty six adult patients with non-Hodgkin's lymphoma were characterized according to nutritional status (percent of weight loss as compared to usual body weight, serum albumin, serum cholinesterase, number of lymphocytes) and rate of incorporation of 3H thymidine labelling index in the tumor tissue. The values of serum albumin, serum cholinesterase and lymphocytes were subdivided into three classes adopting as cut-off points the tertile values of their distribution, while weight loss was scored as a “no” and a “yes”. The association between nutritional parameters and labelling index was evaluated by a univariate analysis (X2 test and Mantel-Haenszel X2 test and the odds ratio) and by a logistic multiple regression model.

Results

Results of the univariate analysis show a statistically significant association between “poor” nutritional status (depressed nutritional indexes) and “high” labelling index (increased tumoural growth), while the multiple regression analysis found that the only significant association was that between low serum cholinesterase and high labelling index.

Conclusions

These data demonstrate for the first time in a large series of patients that maintenance of a good nutritional status does not have any deleterious effect on the tumor growth.

Perioperative nutrition support in cancer patients

Malnutrition and weight loss negatively affect outcomes in surgical cancer patients. Decades of research have sought to identify the most appropriate use of nutrition support in these patients. National and international guidelines help to direct clinicians' use of nutrition support in surgical patients, but a number of specific issues concerning the use of nutrition support continue to evolve. This review focuses on 5 key issues related to perioperative nutrition support in cancer patients: (1) Which perioperative cancer patients should receive nutrition support? (2) How can the nutrition status and requirements of these patients be optimally assessed? (3) What is the optimal route of administration (parenteral nutrition vs enteral nutrition) and composition of nutrition support in this setting? (4) When should feedings be initiated? (5) What is the role of glycemic control in these patients?

ESPEN Guidelines on Parenteral Nutrition: non-surgical oncology

Parenteral nutrition offers the possibility of increasing or ensuring nutrient intake in patients in whom normal food intake is inadequate and enteral nutrition is not feasible, is contraindicated or is not accepted by the patient. These guidelines are intended to provide evidence-based recommendations for the use of parenteral nutrition in cancer patients. They were developed by an interdisciplinary expert group in accordance with accepted standards, are based on the most relevant publications of the last 30 years and share many of the conclusions of the ESPEN guidelines on enteral nutrition in oncology. Under-nutrition and cachexia occur frequently in cancer patients and are indicators of poor prognosis and, per se, responsible for excess morbidity and mortality. Many indications for parenteral nutrition parallel those for enteral nutrition (weight loss or reduction in food intake for more than 7-10 days), but only those who, for whatever reason cannot be fed orally or enterally, are candidates to receive parenteral nutrition. A standard nutritional regimen may be recommended for short-term parenteral nutrition, while in cachectic patients receiving intravenous feeding for several weeks a high fat-to-glucose ratio may be advised because these patients maintain a high capacity to metabolize fats. The limited nutritional response to the parenteral nutrition reflects more the presence of metabolic derangements which are characteristic of the cachexia syndrome (or merely the short duration of the nutritional support) rather than the inadequacy of the nutritional regimen. Perioperative parenteral nutrition is only recommended in malnourished patients if enteral nutrition is not feasible. In non-surgical well-nourished oncologic patients routine parenteral nutrition is not recommended because it has proved to offer no advantage and is associated with increased morbidity. A benefit, however, is reported in patients undergoing hematopoietic stem cell transplantation. Short-term parenteral nutrition is however commonly accepted in patients with acute gastrointestinal complications from chemotherapy and radiotherapy, and long-term (home) parenteral nutrition will sometimes be a life-saving maneuver in patients with sub acute/chronic radiation enteropathy. In incurable cancer patients home parenteral nutrition may be recommended in hypophagic/(sub)obstructed patients (if there is an acceptable performance status) if they are expected to die from starvation/under nutrition prior to tumor spread.

Glucose-based total parenteral nutrition does not stimulate glucose uptake by humans tumours

BACKGROUND

Since glucose represents the preferred fuel for cancer cells, there is some debate about the potential stimulation of tumour metabolism induced by a glucose-based total parenteral nutrition (TPN) in cancer patients.

METHODS

We investigated the uptake of [18]2-fluoro-2-deoxy-D-glucose (FDG) through the positron emission tomography of the healthy liver and of the tumour in 12 patients with liver metastases from colorectal cancer. We determined whether FDG uptake by the tumour in fasting conditions was affected by the subsequent administration of a glucose-based (GTPN) or a lipid-based (LTPN) containing glucose 4 mg/kg/min or lipid 2 mg/kg/min, respectively, as non-protein energy source.

RESULTS

The data showed that FDG uptake by the metastases was 3-3.6 times higher than by the healthy liver in fasting conditions and it was not significantly affected by the subsequent administration of GTPN or LTPN.

CONCLUSIONS

We speculated that, despite glucose being the preferred fuel for cancer cells, its disproportionately high uptake even in fasting conditions makes the glucose consumption unable to be modulated by a further supply of glucose or lipid.

Inhibition of vascular endothelial growth factor by octreotide in colorectal cancer patients

Vascular endothelial growth factor (VEGF) seems to be essential for angiogenesis and for the growth of colorectal cancer; thus its inhibition can arrest tumor growth and decrease metastatic potential. Octreotide has been shown to inhibit growth of colorectal tumors in vitro and in vivo. Part of the antiproliferative activity of octreotide could be related to its antiangiogenic properties. Effects of octreotide on VEGF expression were evaluated in 35 patients with operable colorectal cancer receiving octreotide for 2 weeks before surgery. Tissue VEGF expression and serum VEGF concentrations were determined before and after treatment with octreotide. There was a statistically significant reduction in the tissue VEGF expression both considering the percentage of VEGF positive cells (P = 0.006) and the intensity of VEGF staining (P = 0.003). A similar significant reduction was observed in serum values of VEGF (P = 0.03). The present study indicates that octreotide inhibits expression of VEGF in colorectal cancer patients, and, furthermore, that serum VEGF expression correlates with tissue VEGF, representing a safe method to monitor the activity of antiangiogenic agents.

Nutritional support of the cancer patient: issues and dilemmas

Malnutrition in cancer patients results from multifactorial events and is associated with an alteration of quality of life and a reduced survival. A simple nutritional assessment program and early counselling by a dietitian are essential to guide nutritional support and to alert the physician to the need for enteral (EN) or parenteral nutrition (PN). A daily intake of 20-35 kcal/kg, with a balanced contribution of glucose and lipids, and of 0.2-0.35 g nitrogen/kg is recommended both for EN and PN, with an adequate provision of electrolytes, trace elements and vitamins. EN, always preferable for patients with an intact digestive tract, and PN are both safe and effective methods of administering nutrients. The general results in clinical practice suggest no tumor growth during nutritional support. The indiscriminate use of conventional EN and PN is not indicated in well-nourished cancer patients or in patients with mild malnutrition. EN or PN is not clinically efficacious for patients treated with chemotherapy or radiotherapy, unless there are prolonged periods of GI toxicity, as in the case of bone marrow transplant patients. Severely malnourished cancer patients undergoing major visceral surgery may benefit from perioperative nutritional support, preferably via enteral access. Nutritional support in palliative care should be based on the potential risks and benefits of EN and PN, and on the patient's and family's wishes. Research is currently directed toward the impact of nutritional pharmacology on the clinical outcome of cancer patients. Glutamine-supplemented PN is probably beneficial in bone marrow transplant patients. Immune diets are likely to reduce the rate of infectious complications and the length of hospital stay after GI surgery. Further studies are needed to determine the efficacy of such novel approaches in specific populations of cancer patients, and should also address the question of the overall cost-benefit ratio of nutritional pharmacology, and the effect of nutritional support on length and quality of life.

Prognosis of advanced pancreatic cancer patients with reference to calorie intake

Progressive weight loss and nutritional deterioration are commonly found in patients with advanced pancreatic cancer. There have been few studies of whether nutritional support improves survival for these patients. We retrospectively investigated the relationship between calorie intake and survival in 50 patients who died from cancer. The survival period was calculated from the day when their serum albumin level measured < 3.0 mg/dl. Total calorie intake was calculated on the basis of diet and parenteral nutrition for the week before the day when serum albumin levels fell to < 3.0 mg/dl. Patients were divided into a low- and a high-calorie intake group using the median of calorie intake per predictive basal metabolism. The survival period was significantly longer for the high- than for the low-calorie intake group (median 50 vs. 32 days, p = 0.02). We also investigated the relationships between calories of parenteral nutrition and survival. High-calorie parenteral nutrition subgroups tended to survive longer than low-calorie parenteral nutrition subgroups irrespective of enteral nutrition. Sufficient calorie intake may have the potential to prolong survival for patients with advanced pancreatic cancer.

Effect of glucagon on protein synthesis in human rectal cancer in situ

OBJECTIVE

The purpose of this study was to determine the effect of glucagon or placebo on the rate of tumor fractional protein synthesis in situ in patients with localized rectal cancer who were not malnourished, demonstrated normal glucagon concentrations, and could therefore be used as a model to study the glucagon effect.

SUMMARY BACKGROUND DATA

Cancer cachexia is associated with an increased concentration of counterregulatory hormones, including glucagon. This altered hormonal milieu may not only contribute to malnutrition, but also promote tumor growth, because previous experimental work suggests that glucagon can cause human colorectal tumor cells to proliferate. Corresponding mechanisms in vivo have, thus far, not been investigated.

METHODS

Advanced mass spectrometry techniques (capillary gas chromatography [GC]/combustion isotope ratio mass spectrometry [IRMS]) were used to determine directly the incorporation rate of 1-[13C]-leucine into tissue protein. Because GC/IRMS requires only a small sample volume, three consecutive endoscopic biopsies could be obtained from the same tumor to determine isotopic enrichments at baseline, after a 4-hour glucagon infusion (3 ng/kg/min), or after placebo.

RESULTS

In patients with localized rectal cancer, glucagon caused the tumor fractional protein synthetic rate to double (2.25+/-0.49 %/hr, p < 0.05 vs. 1.16+/-0.30 basal). In contrast, tumor protein synthesis declined over time in controls (placebo) (0.67+/-0.09 %/hr, p < 0.05 vs. 1.11+/-0.16 basal).

CONCLUSIONS

Tumor protein synthesis and growth can be stimulated by glucagon in situ. Therefore, elevated glucagon concentrations in cachectic cancer patients should be considered detrimental and attempts made to prevent this specific response of the body to the malignant disease.

The role of total parenteral nutrition for patients with irreversible bowel obstruction secondary to gynecological malignancy

Two patients received total parenteral nutrition (TPN) to manage irreversible bowel obstruction secondary to gynecological malignancy. The use of TPN prolonged their lives considerably, but also led to complications, both from the TPN and from the natural progression of the cancers. Although TPN is increasingly considered as a possible treatment for selected patients with malignant bowel obstruction who are not suitable for surgery, the literature regarding this practice is conflicting. It should be considered only in those patients with good performance status, and then after careful attention to not only the likely medical and symptomatic outcomes, but also the ethical implications of such a management strategy.

Bromodeoxyuridine: a diagnostic tool in biology and medicine, Part III. Proliferation in normal, injured and diseased tissue, growth factors, differentiation, DNA replication sites and in situ hybridization

This paper is a continuation of parts I (history, methods and cell kinetics) and II (clinical applications and carcinogenesis) published previously (Dolbeare, 1995 Histochem. J. 27, 339, 923). Incorporation of bromodeoxyuridine (BrdUrd) into DNA is used to measure proliferation in normal, diseased and injured tissue and to follow the effect of growth factors. Immunochemical detection of BrdUrd can be used to determine proliferative characteristics of differentiating tissues and to obtain birth dates for actual differentiation events. Studies are also described in which BrdUrd is used to follow the order of DNA replication in specific chromosomes, DNA replication sites in the nucleus and to monitor DNA repair. BrdUrd incorporation has been used as a tool for in situ hybridization experiments.

Total nutritional manipulation in humans: report of acancer patient

We report here on a patient requiring home total parenteral nutrition (TPN) for a huge intra-abdominal desmoid associated with chronic small bowel pseudo-obstruction who was kept on a special lipid-based calorie regimen for 5 months. The rationale was to attempt to feed the host with a minimal stimulation of tumour growth by using lipid as caloric substrate instead of glucose which is utilized by the tumour. Gluconeogenesis was tentatively inhibited at the level of phosphoenolpyruvate-carboxy-kinase through the oral intake of hydrazine sulphate. The regimen consisted of 28 non-protein lipid Kcal/kg/day plus 1.5 g amino acid per kg/day. Only a small amount of glucose (approx. 40 g/day) was allowed. Tolerance to the regimen was good and body weight maintained. Liver enzymes remained within the normal range and liver sonography was normal throughout the 5 months' therapy and there were no episodes of symptomatic hypoglycaemia. The tumour volume did not substantially change.

Nutritional issues in cancer management

The objective of this article was to investigate the relationship between nutrition and cancer, as it relates to the initiation, promotion, and treatment of tumor growth. English-language studies published in the last 25 years were retrieved using MEDLINE, bibliographies, and consultation with experts. MEDLINE search terms included "cancer", "malnutrition," and "nutritional support." In vitro and in vivo controlled studies addressing the impact of nutritional factors on cancer prevention and treatment were selected. Approximately 30% of cancers in the Western countries are diet-related. The presence of malignancy affects patients' nutritional status negatively, leading to increased morbidity and mortality. Standard nutritional support (both enteral and parenteral) is not always effective in significantly improving outcome in malnourished cancer patients, due to characteristic changes in host metabolism. Preliminary studies suggest that newer nutritional-pharmacologic agents may be beneficial in counteracting the derangement of host metabolism, and consequently in ameliorating cancer patients' nutritional status and outcome of malnourishment. This review suggests that dietary manipulations and nutritional-pharmacologic therapy might be highly effective adjuncts in controlling the symptoms of patients with neoplastic disease.

A comparison of cellular proliferation markers in squamous cell carcinoma of the head and neck

Head and neck squamous cell carcinoma has a relatively good prognosis but treatment may be at the expense of function and quality of life. Various host and tumour parameters have been studied in an attempt to predict the course of the disease but without success. It has been hoped that laboratory based methods, particularly those based on molecular biology, may prove more useful. Cell kinetic parameters are studied in this paper. The present study includes 75 patients with a proven squamous cell carcinoma of the head and neck at various sites and undergoing various forms of treatment. The patient's mean age was 62 years and the median survival rate 45 months. Immunohistochemical techniques using Ki67 and PCNA were compared with flow cytometric analysis which included the BRDU labelling index, the duration of S phase, ploidy and potential doubling time. The median PCNA index was 560 and the Ki67 index 298. These indices varied between 980 and 150 for PCNA and 808 and 110 for Ki67. The BRDU labelling index measured by flow cytometry was 8.9 with a range from 25 to 1.6 and the duration of S phase was 14.8 hours. The PCNA index failed to correlate with any host or tumour factors and this failure was also seen in Ki67 indices and also in the flow cytometric parameters. There was a strong correlation between PCNA and Ki67 expression (p < 0.0001). Neither PCNA nor Ki67 values were significantly different between irradiated and nonirradiated tissues nor in sites or in patients who later developed lymph node metastases.(ABSTRACT TRUNCATED AT 250 WORDS)

Use of total parenteral nutrition in children with cancer: a review and some recommendations

Total parenteral nutrition (TPN) is now a standard component of supportive treatment in many pediatric oncology units for patients undergoing intensive therapy. TPN incurs many risks and significant costs, however, that may not always be balanced by major benefits. Infection rates are reported to be high in patients receiving TPN, and TPN use is associated with a range of metabolic problems. With standard TPN regimens, the catabolic state of many intensively treated patients may not be adequately reversed. Because TPN may enhance tumor cell growth, there is justifiable concern about giving TPN when a cancer patient is not also receiving cytotoxic therapy. Recommendations for TPN use in pediatric oncology patients include using TPN formulas containing glutamine to stimulate anabolism and timing TPN cycles to be given just before cytotoxic chemotherapy, when stimulation of tumor growth might actually improve the effectiveness of antimitotic chemotherapy.