Gastric cancer does not affect the expression of atrophy-related genes in human skeletal muscle.

INTRODUCTION: We evaluated the gene expression levels of atrogin-1, MuRF1, myostatin, follistatin, activin A, and inhibin alpha in skeletal muscle samples of patients with gastric cancer and controls. METHODS: We studied 38 cancer patients and 12 controls who underwent surgery for gastric adenocarcinoma and benign abdominal diseases, respectively. A biopsy specimen was obtained from the rectus abdominis muscle from all participants. The relative gene expression of atrogin-1, MuRF1, myostatin, follistatin, activin A, and inhibin alpha was determined by quantitative real-time polymerase chain reaction analysis. RESULTS: Atrogin-1 and MuRF1 mRNA expression was similar between cancer patients and controls and was unaffected by the disease stage or the severity of body weight loss. Transcript levels of myostatin and follistatin did not differ between cases and controls and were similar across disease stages and categories of weight loss. Finally, no differences were detected in activin A and inhibin alpha gene expression between cancer patients and controls. CONCLUSIONS: In skeletal muscle, the gene expression of atrogin-1, MuRF1, myostatin, follistatin, activin A, and inhibin alpha is not affected by the presence of cancer. The expression of atrophy-related genes is unaffected by the disease stage and the degree of weight loss.

Calpain activity is increased in skeletal muscle from gastric cancer patients with no or minimal weight loss.

The influence of cancer on skeletal muscle calpain expression and activity in humans is poorly understood. We tested the hypothesis that calpain activity is increased in skeletal muscle from gastric cancer patients with no or <5% weight loss. Muscle biopsies were obtained from rectus abdominis muscle in 15 patients who underwent surgery for gastric cancer and had <5% weight loss and also in 15 control patients. Calpain activity was determined using a calpain-specific substrate in the absence or presence of calcium. The expression of µ- and m-calpain, calpastatin, atrogin-1, and MuRF1 was determined by real-time polymerase chain reaction. Calpain activity was increased by 70% in cancer patients compared with controls. There were no differences in mRNA levels for µ- and m-calpain, calpastatin, atrogin-1, or MuRF1 between control and cancer patients. Calpain activity may be increased in muscle from gastric cancer patients even before changes in molecular markers of muscle wasting and significant weight loss occur.

Taste intensity and hedonic responses to simple beverages in gastrointestinal cancer patients.

Changes in the taste of food have been implicated as a potential cause of reduced dietary intake among cancer patients. However, data on intensity and hedonic responses to the four basic tastes in cancer are scanty and contradictory. The present study aimed at evaluating taste intensity and hedonic responses to simple beverages in 47 anorectic patients affected by gastrointestinal cancer and in 55 healthy subjects. Five suprathreshold concentrations of each of the four test substances (sucrose in black current drinks, citric acid in lemonade, NaCl in unsalted tomato juice, and urea in tonic water) were used. Patients were invited to express a judgment of intensity and pleasantness ranging from 0 to 10. Mean intensity scores directly correlated with concentrations of sour, salty, bitter, and sweet stimuli, in both normals and those with cancer. Intensity judgments were higher in cancer patients with respect to sweet (for median and high concentrations, P<0.05), salty (for all concentrations, P<0.05), and bitter tastes (for median concentration, P<0.01). Hedonic function increased with the increase of the stimuli only for the sweet taste. A negative linear correlation was found between sour, bitter, and salty concentrations and hedonic score. Both in cancer patients and in healthy subjects, hedonic judgments increased with the increase of the stimulus for the sweet taste (r=0.978 and r=0.985, P=0.004 and P=0.002, respectively), and decreased for the salty (r=-0.827 and r=-0.884, P=0.084 and P=0.047, respectively) and bitter tastes (r=-0.990 and r=-0.962, P=0.009 and P=0.001, respectively). For the sour taste, the hedonic scores remained stable with the increase of the stimulus in noncancer controls (r=-0.785, P=0.115) and decreased in cancer patients (r=-0.996, P=0.0001). The hedonic scores for the sweet taste and the bitter taste were similar in cancer patients and healthy subjects, and these scores were significantly higher in cancer patients than in healthy subjects for most of the concentrations of the salty taste and all the concentrations of the sour taste. The present study suggests that cancer patients, compared to healthy individuals, have a normal sensitivity, a normal liking for pleasant stimuli, and a decreased dislike for unpleasant stimuli. Moreover, when compared to controls, they show higher hedonic scores for middle and high concentrations of the salty taste and for all concentrations of the sour taste. Further studies are needed to evaluate whether these changes observed in cancer patients translate into any alteration in dietary behavior and/or food preferences.

Parenteral nutrition does not stimulate tumor proliferation in malnourished gastric cancer patients.

BACKGROUND: The present study evaluated the effects of preoperative parenteral nutrition (PN) on tumor cell proliferation in malnourished gastric cancer patients. METHODS: Twenty malnourished patients affected by gastric cancer were randomized to receive the standard hospital oral diet (control group) or the standard hospital oral diet plus PN (PN group; 0.2 g/kg/d of nitrogen and 30 nonprotein kcal/kg/d). Samples of tumor tissue and surrounding health mucosa were taken by endoscopic biopsies and from the operative specimen, immediately after resection. Tissues were sent for histologic examination and prepared for flow cytometry and for the measurement of the uptake of bromodeoxyuridine (BduR) by cells after in vitro exposure to the agent. The BduR uptake is largely used to assess the proportion of cells actively synthesizing DNA and is one of the principle methods used to measure tumor proliferation. RESULTS: In the PN group, the mean percentage of tumor cells incorporating BduR was 2.51% +/- 1.7% in the endoscopic samples and 1.52% +/- 0.8% in the operative specimens (p = .2). In the normal mucosa, the mean percentage of cells incorporating BduR was 2.24% +/- 1.8% and 1.13% +/- 1.1%, respectively (p = .1). In the control group, the percentage of cells incorporating BduR in the normal mucosa was 1.26% +/- 1.1% at endoscopy and 0.41% +/- 0.3% at surgery (p = .2), whereas the percentage of cells incorporating BduR in the tumor tissue was 1.41% +/- 1.2% at endoscopy and 0.48% +/- 0.6% at surgery (p = .2). The percentage of S-phase cells documented by flow cytometry in the PN group was: in the tumor, 6.6% +/- 2.9% in the endoscopic samples and 5.7% +/- 2.5% in the operative specimens (p = .6); in the normal mucosa, 5.8% +/- 2.5% at endoscopy and 5.4% +/- 0.9% at surgery (p = .7). In the control group, the percentage of proliferating cells measured by flow cytometry was 4.9% +/- 3.2% in the normal mucosa taken by endoscopic biopsy and 5.3% +/- 1.4% in the normal mucosa taken from the operative specimens (p = .8), whereas it was 11.4% +/- 7.2% in the tumor taken with endoscopic biopsy and 9.7% +/- 4% in the tumor tissue taken from the surgical specimens (p = .7). CONCLUSIONS: The present study suggests that PN does not stimulate tumor proliferation in malnourished patients affected by gastric cancer.

Skeletal muscle apoptosis is not increased in gastric cancer patients with mild-moderate weight loss.

Numerous experimental and clinical studies have shown that skeletal muscle apoptotis may increase in wasting conditions and suggest that apoptosis might contribute to the loss of lean body mass. Data in cancer patients are still lacking. The present study aimed at verifying whether apoptosis was enhanced in the skeletal muscle of 16 patients with gastric cancer with respect to controls. A biopsy specimen was obtained from the rectus abdominis muscle. The occurrence of apoptosis in muscle biopsies was determined morphologically by the fluorescent transferase-mediated dUTP nick end labeling assay and by immunohistochemistry for caspase-3 and caspase-1. Mean weight loss was 6+/-2% in cancer patients and 0.5+/-0.1% in controls (p<0.0001). Serum albumin levels (g/dL) were 3.7+/-0.3 in cancer patients and 4.1+/-0.2 in controls (p<0.05). The percentage of apoptotic myonuclei was similar in cancer patients and in controls (1.5+/-0.3 versus 1.4+/-0.2, respectively; p=ns), in gastric cancer patients with mild (1.6+/-0.4) or moderate-severe weight loss (1.4+/-0.5) (p=ns), and in the different stages of disease (stages I-II: 1.5+/-0.7; stage III: 1.3+/-0.4; stage IV: 1.6+/-0.3; p=ns). By immunohistochemistry, caspase-1 and caspase-3 positive fibers were absent in controls and in neoplastic patients. Poly-ADP-ribosyl polymerase, a typical caspase-3 substrate whose processing is indicative of caspase-3 activation, was not cleaved in muscle biopsies of cancer patients. These data suggest that skeletal muscle apoptosis is not increased in neoplastic patients with mild-moderate weight loss and argue against the hypotheses that caspase-3 activation might be an essential step of myofibrillar proteolysis in cancer-related muscle wasting.

Chemoradiation with raltitrexed (Tomudex) in preoperative treatment of stage II-III resectable rectal cancer: a phase II study.

PURPOSE: To evaluate the impact of preoperative chemoradiation with raltitrexed (Tomudex(1)) on tumor response, sphincter preservation, and toxicity in patients with locally advanced rectal cancer. METHODS AND MATERIALS: Between 1998 and 2002, 54 consecutive patients with Stage T3 or T2N+ resectable rectal carcinoma were treated with preoperative chemoradiation, i.v. bolus of raltitrexed on Days 1, 19, and 38 and concurrent 50 Gy external beam radiotherapy. Surgery was performed 6-8 weeks after the end of chemoradiation. RESULTS: No patients had Grade 4 acute toxicity. Grade 3 acute toxicity occurred in 16.6% of cases and was hematologic in 6 patients and GI in 2. The overall clinical response rate was 88.8%, with a complete response in 5.5%, partial response in 83.3%, and no change in 9.2%. No patient showed disease progression. All patients underwent surgery. Sphincter saving was obtained in 83.3% of patients. No perioperative mortality occurred, and the perioperative morbidity rate was 5.5%. Of 20 resected patients (37%) who were candidates for abdominoperineal resection at diagnosis (anorectal ring distance < or =30 mm), 13 (65%) underwent a sphincter-saving procedure. At pathologic examination, 13 (24%) of 54 patients had a complete pathologic response (pT0) and 10 (18.5%) had rare isolated residual cancer cells (pT, microscopic foci). Overall, 42.5% had major downstaging. The tumor regression grade (TRG), using Mandard's score system, was also applied and was TRG1 in 13 patients, TRG2 in 11, TRG3 in 20, and TRG4 in 10 patients; no patient had TRG5. CONCLUSION: The use of raltitrexed in a neoadjuvant chemoradiation schedule promoted high pathologic tumor downstaging and use of a sphincter-saving procedure. The low toxicity profile supports the rationale to explore raltitrexed combined with other drugs with different biologic targets.

Does nutrition support stimulate tumor growth in humans?

Many studies have been conducted to ascertain if nutrition support (NS), either as parenteral nutrition (PN) or enteral nutrition (EN), stimulates tumor growth and causes cancer progression, but after almost 30 years, the question remains at least in part unresolved. In this study, previous studies were reviewed to evaluate the effect of NS on tumor growth, tumor proliferation, tumor apoptosis, and cancer-related survival in humans. MEDLINE and PubMed were searched using combinations of the following keywords: PN, EN, tumor growth, tumor proliferation, tumor apoptosis, arginine, ω-3 fatty acids, and glutamine. Unfortunately, the effect of nutrition support on tumor growth has been assessed only in terms of tumor proliferation, whereas the interferences on tumor apoptosis have never been determined. Overall, the results seem conflicting and inconclusive. Similarly, it remains unknown if PN or EN enriched with specific nutrients such as arginine, ω-3 fatty acids, and glutamine can affect tumor growth in humans. It is hoped that further studies will elucidate if NS with conventional or specific nutrients stimulates tumor proliferation, interferes with tumor apoptosis, and causes cancer progression.

Skeletal muscle of gastric cancer patients expresses genes involved in muscle regeneration.

Experimental studies have suggested that defective skeletal muscle regeneration could contribute to muscle wasting in cancer patients. However, data in humans are still lacking. In this study we aimed to assess the expression of the genes involved in muscle regeneration in gastric cancer patients. The RNA expression of the genes involved in muscle regeneration was assessed in the rectus abdominis muscle of patients with gastric cancer (n=30) and in age-matched control subjects (n=8). The Pax7 expression was significantly increased in the muscle of gastric cancer patients, either in the first stages of the disease or in stages IIIA and B. The increased expression was present both in stages IA and B and in stages II and III. The MyoD espression was also higher in the cancer patients than in the controls. However, the increased MyoD expression was present only in stages IA and B and not in the more advanced stages of the disease. The Myf5 expression, as well as that of the neonatal isoform of Myosin Heavy Chain (nMHC) did not differ significantly between the cancer patients and the controls. The necdin expression was negligible in healthy adult muscles and was significantly up-regulated in the muscle of gastric cancer patients. Its expression was highly increased in stages IA and B while it was similar to the control in stages II and III. The results of the present study show that in the skeletal muscle of gastric cancer patients, the expression of the genes involved in muscle regeneration is increased with respect to the controls.

Expression of NF-kappaB and IkappaB proteins in skeletal muscle of gastric cancer patients.

The mechanisms eliciting cancer cachexia are not well understood. Wasting of skeletal muscle is problematic because it is responsible for the clinical deterioration in cancer patients and for the ability to tolerate cancer treatment. Studies done on animals suggest that nuclear factor of kappa B (NF-kappaB) signalling is important in the progression of muscle wasting due to several types of tumours. However, there are no published studies in humans on the role of NF-kappaB in cancer cachexia. In this project, we studied the rectus abdominis muscle in patients with gastric tumours (n=14) and in age-matched control subjects (n=10) for markers of NF-kappaB activation. Nuclear levels of p65, p50 and Bcl-3 were the same in both groups of subjects. However, phospho-p65 was elevated by 25% in the muscles of cancer patients. In addition, expression of the inhibitor of kappa B alpha (IkappaBalpha) was decreased by 25% in cancer patients. Decreased expression of IkappaBalpha reflects its degradation by one of the IkappaBalpha kinases and is a marker of NF-kappaB activation. Interestingly, there was no correlation between the stage of cancer and the extent of IkappaBalpha decrease, nor was there a correlation between the degree of cachexia and decreased IkappaBalpha levels. This suggests that the activation of NF-kappaB is an early and sustained event in gastric cancer. The work implicates the NF-kappaB signalling in the initiation and progression of cancer cachexia in humans and demonstrates the need for additional study of this pathway; it also recommends NF-kappaB signalling as a therapeutic target for the amelioration of cachexia as has been suggested from studies done on rodents.

Skeletal muscle in cancer cachexia: the ideal target of drug therapy.

Cancer cachexia is a debilitating and life-threatening syndrome that accounts for at least 20% of deaths in neoplastic patients. Cancer cachexia significantly impairs quality of life and response to anti-neoplastic therapies, increasing morbidity and mortality of cancer patients. The loss of lean body mass is the main characteristic of cancer cachexia and the principal cause of function impairment, fatigue and respiratory complications. It is the result of an imbalance between protein synthesis and protein degradation, the mechanisms underlying such alteration being multiple and partially known. Current therapy of cancer cachexia continues to be extremely poor. However, in the last decade, the attention has focused just on the skeletal muscle, as a potential target of therapy, with the aim to discover drugs capable to inhibit the catabolic processes and to stimulate the anabolic pathways. The skeletal muscle has been faced at different levels such as the mediators (cytokines and tumor-derived factors), the receptors (TNF-alpha and androgen receptors), the proteolytic pathways (calpains and ubiquitin-proteasome), the intracellullar signalling pathways (NF-kB, AP-1, FOXO, PKR), and the negative modulators of muscle growth/hypertrophy (myostatin, GSK3-beta). Most of the drugs that have been tested have shown to be effective, at least in experimental models of cancer cachexia. It remains to define their safety, tolerance and efficacy in humans through large, adequate, clinical trials. However, the impression is that there is a light at the back of the tunnel.

Proteasome activities in the rectus abdominis muscle of young and older individuals.

Sarcopenia is one of the most striking effects of age, the causes and the pathogenic mechanisms being largely unknown. Unfortunately, there is limited information on the effect of aging on muscle protein breakdown in basal conditions. The present study aimed at investigating if skeletal muscle ubiquitn mRNA levels and proteasome activities vary with age in healthy individuals. Ub mRNA levels were measured by northern blot analysis whereas proteasome activities were determined by evaluating the cleavage of specific fluorogenic substrates in the rectus abdominis muscle of 14 healthy male individuals. Patients were divided in three groups according to the age: (1) 20-30 years (N = 3); (2) 31-64 years (N = 5); (3) > or = 65 years (N = 6). Quantitation of the ubiquitin mRNA levels (expressed in arbitrary units) (mean (SD) showed no differences among the three groups of age (20-30 years: 1352 +/- 441; 31-64 years: 1324 +/- 439; > or = 65 years: 884 +/- 400; P = 0.33). The correlation between age and muscle ubiquitin mRNA levels was not statistically significant (r = -0.4, P = 0.26). The three proteasome activities, chymotrypsin-like (CTL), trypsin-like (TL) and peptidyl-gutamyl-peptidase (PGP), expressed as nkatal x 10(-3)/mg protein, were similar in the three groups of patients stratified according to the age. There was no correlation between age with either CTL (r = 0.22, P = 0.4), PGP (r = 0.002, P = 0.9), and TL (r = 0.28, P = 0.33) activities. In conclusion, the present study shows that the skeletal muscle proteasome activities do not differ with age in healthy male individuals.

Infusional 5-fluorouracil and ZD1839 (Gefitinib-Iressa) in combination with preoperative radiotherapy in patients with locally advanced rectal cancer: a phase I and II Trial (1839IL/0092).

PURPOSE: To report the final data of a Phase I and II study (1839IL/0092) on the combination of an anti-epidermal growth factor receptor drug (gefitinib), infusional 5-fluorouracil, and preoperative radiotherapy in locally advanced, resectable rectal cancer. METHODS AND MATERIALS: Patients received 45 Gy in the posterior pelvis plus a boost of 5.4 Gy on the tumor and corresponding mesorectum. Infusional 5-fluorouracil (5-FU) and gefitinib (250 and 500 mg/day) were delivered during all radiotherapy course. An IORT boost of 10 Gy was allowed. The main endpoints of the study were to establish dose-limiting toxicity (DLT) and to evaluate the rate of pathologic response according to the tumor regression grade (TRG) Mandard score. RESULTS: A total of 41 patients were enrolled. The DLT was not reached in the 6 patients enrolled in the dose-escalation part of the study. Of the 33 patients in the Phase II, TRG 1 was recorded in 10 patients (30.3%) and TRG 2 in 7 patients (21.2 %); overall 17 of 33 patients (51.5%) had a favorable endpoint. Overall, Grade 3+ toxicity was recorded in 16 patients (41%); these included Grade 3+ gastrointestinal toxicity in 8 patients (20.5%), Grade 3+ skin toxicity in 6 (15.3%), and Grade 3+ genitourinary toxicity in 4 (10.2%). A dose reduction of gefitinib was necessary in 24 patients (61.5%). CONCLUSIONS: Gefitinib can be associated with 5-FU-based preoperative chemoradiation at the dose of 500 mg without any life-threatening toxicity and with a high pCR (30.3%). The relevant rate of Grade 3 gastrointestinal toxicity suggests that 250 mg would be more tolerable dose in a neaoadjuvant approach with radiotherapy and infusional 5-FU.

Novel treatments for cancer cachexia.

Cancer cachexia is a debilitating and life-threatening syndrome characterised by anorexia, body weight loss, loss of adipose tissue and skeletal muscle, and accounts for > or = 20% of deaths in neoplastic patients. Cancer cachexia significantly impairs quality of life and response to antineoplastic therapies, increasing the morbidity and mortality of cancer patients. Muscle wasting is the most important phenotypic feature of cancer cachexia and the principle cause of function impairment, fatigue and respiratory complications, and is mainly related to a hyperactivation of muscle proteolytic pathways. Existing therapeutic strategies have proven to be only partially effective. In the last decade, the correction of anorexia, the inhibition of catabolic processes and the stimulation of anabolic pathways in muscle has been attempted pharmacologically, giving encouraging results in animal models and through preliminary clinical trials.

Cancer cachexia: it's time for more clinical trials.

Cancer cachexia (CC) is a multifactorial paraneoplastic syndrome characterized by anorexia, body weight loss, loss of adipose tissue and skeletal muscle, accounting for at least 20% of deaths in neoplastic patients. CC significantly impairs quality of life and response to anti-neoplastic therapies, increasing morbidity and mortality of cancer patients. Muscle wasting is the most important phenotypic feature of CC and the principal cause of function impairment, fatigue and respiratory complications, mainly related to a hyperactivation of muscle proteolytic pathways. Most current therapeutic strategies to counteract CC have proven to be only partially effective. In the last decade, the correction of anorexia, the inhibition of catabolic processes and the stimulation of anabolic pathways in muscle have been attempted pharmacologically with encouraging results in animal models and through preliminary clinical trials. However, data in the clinical setting are still scanty and non definitive. It is time to start prospective, randomized, controlled trials to evaluate which drugs are effective in counteracting the loss of lean of muscle mass and in improving nutritional status and quality of life in patients affected by cancer-related cachexia.