Myeloperoxidase-positive cell infiltration of normal colorectal mucosa is related to body fatness and is predictive of adenoma occurrence.

Body fatness is a risk factor for colorectal cancer, and promotes an inflammatory environment. Indeed, inflammation in normal colorectal mucosa may be a factor linking body fatness to colorectal carcinogenesis. In this study, we evaluated myeloperoxidase (MPO)-positive cells infiltration of normal colorectal mucosa as a marker of cancer-promoting inflammation in overweight and obese subjects. One hundred and three subjects with normal colonoscopy entered the study. Waist circumference (WC) and body mass index (BMI) were measured, and MPO-positive cells on histological sections of biopsies of normal colorectal mucosa were counted under a light microscope. The occurrence of adenomas was then evaluated on follow-up colonoscopies. Mean MPO-positive cell count (±s.e.m.) was higher in subject with a WC equal or above the obesity cutoff values according to gender (2.63±0.20 vs 2.06±0.18, P=0.03), and in subjects with BMI equal or above 25 kg m-2 (2.54±0.18 vs 1.97±0.20, P=0.03). A Cox proportional hazard model showed that mean MPO-positive cell count in normal colorectal mucosa was the only factor independently related to occurrence of adenomas in follow-up colonoscopies. Though preliminary, these results show that MPO-positive cell infiltration in normal colorectal mucosa is related with body fatness, as evaluated by WC and BMI, and it may be considered a useful and simple marker to estimate adenoma occurrence risk.

Clinical and molecular features of attenuated adenomatous polyposis in northern Italy.

BACKGROUND: Attenuated familial adenomatous polyposis (AFAP) is characterized by the presence of 10-99 colorectal adenomas. The disease may be associated with mutations in either APC or MUTYH genes. We purposed to evaluate the contribution of adenomatous polyposis coli (APC) and MutY homologue (MUTYH) germline alterations to the AFAP phenotype and to identify genotype/phenotype correlations. METHODS: During counselling for familial adenomatous polyposis (FAP), 91 probands (and 107 affected individuals) who met the criteria of AFAP were identified. Eighty-two families were screened for constitutional mutations of the APC and MUTYH genes. RESULTS: MUTYH mutations were detected in 21 families (25.6 % of the 82 tested), and APC mutations in 7 (8.5 %). Overall, constitutional alterations were found in 34.1 % of the probands. Patients with APC mutations were younger at cancer onset and had a higher mean number of polyps (48.5 ± 33.0 in APC+ individuals vs. 35.7 ± 24.9 in MUTYH+ individuals, and 33.2 ± 18.4 in the "no mutation" group). Clinical features rendered the "no mutation" group closer to MUTYH+ than to the APC+ group. Colorectal cancer at diagnosis was detected in 40 % of AFAP individuals. CONCLUSIONS: AFAP is a new clinical entity with its frequency in the general population still undefined. The number of adenomas varies greatly, with an average of 30-40 lesions. The molecular basis of AFAP can be established in approximately 1/3 of the patients. Both MUTYH and APC genes are implicated in AFAP, though the role of MUTYH is of considerably greater relevance.

A mononucleotide markers panel to identify hMLH1/hMSH2 germline mutations.

Hereditary NonPolyposis Colorectal Cancer (Lynch syndrome) is an autosomal dominant disease caused by germline mutations in a class of genes deputed to maintain genomic integrity during cell replication, mutations result in a generalized genomic instability, particularly evident at microsatellite loci (Microsatellite Instability, MSI). MSI is present in 85-90% of colorectal cancers that occur in Lynch Syndrome. To standardize the molecular diagnosis of MSI, a panel of 5 microsatellite markers was proposed (known as the "Bethesda panel"). Aim of our study is to evaluate if MSI testing with two mononucleotide markers, such as BAT25 and BAT26, was sufficient to identify patients with hMLH1/hMSH2 germline mutations. We tested 105 tumours for MSI using both the Bethesda markers and the two mononucleotide markers BAT25 and BAT26. Moreover, immunohistochemical evaluation of MLH1 and MSH2 proteins was executed on the tumours with at least one unstable microsatellite, whereas germline hMLH1/hMSH2 mutations were searched for all cases showing two or more unstable microsatellites. The Bethesda panel detected more MSI(+) tumors than the mononucleotide panel (49.5% and 28.6%, respectively). However, the mononucleotide panel was more efficient to detect MSI(+) tumours with lack of expression of Mismatch Repair proteins (93% vs 54%). Germline mutations were detected in almost all patients whose tumours showed MSI and no expression of MLH1/MSH2 proteins. No germline mutations were found in patients with MSI(+) tumour defined only through dinucleotide markers. In conclusion, the proposed mononucleotide markers panel seems to have a higher predictive value to identify hMLH1 and hMSH2 mutation-positive patients with Lynch syndrome. Moreover, this panel showed increased specificity, thus improving the cost/effectiveness ratio of the biomolecular analyses.

The role of hPMS1 and hPMS2 in predisposing to colorectal cancer.

Hereditary nonpolyposis colorectal cancer (HNPCC) is attributable to a deficiency of mismatch repair. Inactivation of DNA mismatch repair underlies the genesis of microsatellite instability in colorectal cancer. Germline mutations in three DNA mismatch repair genes, hMSH2, hMLH1, and hMSH6, have been found to segregate in HNPCC and HNPCC-like families. The two DNA mismatch repair genes hPMS1 and hPMS2 have also been suggested to predispose to HNPCC. In this study, 84 HNPCC and HNPCC-like kindreds without known mutations in the other three known DNA mismatch repair genes were screened for germline mutations in the hPMS1 or hPMS2 gene. No clear-cut pathogenic mutations were identified. Conversion technology was used to detect a large hMSH2 deletion in two affected members of the kindred in which the hPMS1 mutation was originally reported, whereas the hPMS1 mutation was only present in one of these two individuals. Since the hPMS1 and hPMS2 genes were first reported, germline mutations in hPMS2 have been demonstrated primarily in patients with Turcot's syndrome. However, no mutation in any of the two genes has been found to segregate in HNPCC families. Until there is better evidence for an increased colorectal cancer risk associated with germline mutations in these genes, a conservative interpretation of the role of mutations in these genes is advised.

Microsatellite instability and mismatch-repair protein expression in hereditary and sporadic colorectal carcinogenesis.

Aberrant crypt foci (ACF) are microscopic clusters of altered colonic crypts considered premalignant lesions in the large bowel. Genomic instability at short tandem repeats in the DNA, referred to as microsatellite instability (MSI) is the hallmark of hereditary nonpolyposis colorectal carcinoma (HNPCC) caused by mutations in DNA mismatch-repair genes, mostly hMLH1 and hMSH2. In this study, we evaluated for MSI ACF (n = 16), adenomas (n = 18), carcinomas (n =22), and lymph node metastases (n = 3) from 17 patients with colorectal cancer positive for MSI. Ten patients were members of HNPCC families; 7 patients had no family history of cancer. MSI was found in 7 of 7 (100%) ACF and 11 of 12 (91%) adenomas from patients with HNPCC. MSI was not related to histology and size of ACF. A progressive increase in instability as estimated by the number of shifted bands was observed along the ACF-adenoma-carcinoma sequence. In contrast, two of nine (22%) ACF and none of six adenomas from patients with MSI sporadic carcinoma were unstable at microsatellite loci. hMLH1 or hMSH2 protein expression was altered only in MSI-positive premalignant lesions (ACF and/or adenomas), but not in all MSI-positive lesions in patients with HNPCC. These observations provide evidence of the premalignant nature of ACF in HNPCC and suggest that MSI is a very early event both in HNPCC and in sporadic colorectal carcinogenesis, although in the latter it seems infrequent.

Molecular screening for hereditary nonpolyposis colorectal cancer: a prospective, population-based study.

PURPOSE: Germline mutations in mismatch repair genes predispose to hereditary nonpolyposis colorectal cancer (HNPCC). To address effective screening programs, the true incidence of the disease must be known. Previous clinical investigations reported estimates ranging between 0.5% and 13% of all the colorectal cancer (CRC) cases, whereas biomolecular studies in Finland found an incidence of 2% to 2.7% of mutation carriers for the disease. The aim of the present report is to establish the frequency of the disease in a high-incidence area for colon cancer. PATIENTS AND METHODS: Through the data of the local CRC registry, we prospectively collected all cases of CRC from January 1, 1996, through December 31, 1997 (N = 391). Three hundred thirty-six CRC cases (85.9% of the incident cases) were screened for microsatellite instability (MSI) with six to 12 mono- and dinucleotide markers. MSI cases were subjected to MSH2 and MLH1 germline mutation analysis and immunohistochemistry; the methylation of the promoter region was studied for MLH1. RESULTS: Twenty-eight cases (8.3% of the total) showed MSI. MSI cases differed significantly from microsatellite-stable (MSS) cases for their proximal location (P <.01), high mucinous component (P <.01), and poor differentiation (P =.002). Of MSI cases studied (n = 12), only one with a family history compatible with HNPCC had a germline mutation (in MSH2). Five other patients with a family history of HNPCC (two with MSI and three with MSS tumors) did not show germline mutations. CONCLUSION: We conclude that the incidence of molecularly confirmed HNPCC (one [0.3%] of 336) in a high-incidence area for CRC is lower than in previous biomolecular and clinical estimates.

Aberrant crypt foci in colorectal carcinogenesis. Cell and crypt dynamics.

Aberrant crypt foci (ACF) have been identified on the colonic mucosal surface of rodents treated with colon carcinogens and of humans after methylene-blue staining and observation under a light microscope. Several lines of evidence strongly suggest that ACF with certain morphological, histological, cell kinetics, and genetic features are precursor lesions of colon cancer both in rodents and in humans. Thus, ACF represent the earliest step in colorectal carcinogenesis. This paper has the main purpose of reviewing the evidence supporting this view, with particular emphasis on cell and crypt dynamics in ACF. ACF have been used as intermediate biomarkers of cancer development in animal studies aimed at the identification of colon carcinogens and chemopreventive agents. Recently, evidence has also shown that ACF can be effectively employed in chemopreventive studies also in humans.

Frequency and type of colorectal tumors in asymptomatic high-risk individuals in families with hereditary nonpolyposis colorectal cancer.

In hereditary nonpolyposis colorectal cancer (HNPCC, or Lynch syndrome) a close surveillance is usually proposed to high-risk family members with the ultimate goal of reducing cancer incidence and mortality. Through a specialized registry, between 1984 and 1996, we identified 31 families with clinical features of HNPCC. A total of 390 first-degree relatives of affected patients were considered at high risk for colorectal cancer. The main purposes of this study were: (a) to assess overall compliance; and (b) to evaluate the frequency and morphological features of tumors detected at endoscopy. Two hundred twenty-three subjects could be directly interviewed and colonoscopy strongly recommended. Each of the 86 individuals who underwent colonoscopy was matched to a control of the same age (+/-3 years) and sex (control subjects were seeking endoscopy for constipation, rectal bleeding or abdominal discomfort). Of the 390 individuals traced as "at risk," 223 (57.2%) could be contacted, and, of these, 86 (38.6%, or 22.0% of the total) underwent colonoscopy. One or more colorectal lesions were found in 35 of 86 (40.7%) HNPCC asymptomatic family members and in 15 (17.4%; P < 0.001) controls. In the former group, 29 adenomas were detected in 20 individuals as opposed to 11 adenomas in 9 subjects among controls (P < 0.03). Moreover, adenomas in family members were significantly larger [9.1 +/- 5.9 mm (mean +/- SD) versus 5.8 +/- 3.7 mm; P < 0.02] and more frequently showed a tubulovillous histological type and a high degree of dysplasia. Five colorectal carcinomas (in four patients) were detected among cases (four of which were located between the cecum and the hepatic flexure); only one was detected among controls. Surveillance of high-risk subjects in HNPCC families can be carried out only in a fraction of them, because the majority cannot be reached or refuse to collaborate. On the other hand, the frequency of newly detected lesions among family members and the possible aggressive behavior of the lesions render pancolonoscopy necessary at regular intervals of time.

Clinical features, frequency and prognosis of Dukes' A colorectal carcinoma: a population-based investigation.

The main aim of this study was, through the data of a population-based Registry, to establish the incidence of Dukes' A lesions by year of registration and the main clinical features, and to assess cancer-specific survival. One hundred and eighteen Dukes' A colorectal tumours were diagnosed (in 117 patients) out of 1337 registered between 1984 and 1992 in the Health Care District of Modena, Northern Italy; 94 patients were treated with surgery and 23 with endoscopic polypectomy. The frequency of Dukes' A tumours ranged between 4.8% and 18% by year of registration. Dukes' A carcinomas were significantly more frequent in the distal colon. Only 5 patients (4%) died of their cancer, and in all patients the tumour was localised in the rectum. Carcinomas associated with a poor prognosis did not show any of the biological variables usually associated with an unfavourable outcome, but, our data suggest the possibility of incomplete removal of tumours at surgery.

Survival for colon and rectal cancer in a population-based cancer registry.

Dukes' stage is the most powerful indicator of patient outcome for colorectal cancer. Several cancer survival studies have considered other prognostic variables, but results are often conflicting. We sought to assess the independent value of several clinical and morphological variables in defining colorectal cancer specific survival. 397 colorectal cancer patients diagnosed from 1984 to 1986, and registered in a large bowel cancer registry instituted in a local health district of Northern Italy, were actively followed-up until 31 December 1991. Univariate and multivariate survival analyses were carried out in colon and rectal cancer cases, separately, using the actuarial life-table method and Cox proportional hazard regressions. Crude and specific 5-year survival rates were 37.5 and 41.4%. In univariate analysis, TNM (tumour, nodes and metastases) stage was the strongest predictor of prognosis in both sites. Other variables significantly related to survival were age of patient at diagnosis and pattern of tumour growth in colon cancer, type of differentiation and pattern of tumour growth in rectal cancer. In multivariate analyses, after adjusting for stage, age had a weak but significant negative effect on colon cancer survival, whereas rectal tumours with the infiltrating type of growth had a significantly worse prognosis than those with the expanding type. Colorectal cancer survival should be analysed in the main large bowel subsites in order to define high-risk groups within each TNM stage category.

Staging and survival of colorectal cancer: are we making progress? The 14-year experience of a Specialized cancer Registry.

BACKGROUND AND AIMS: It is still unclear whether recent advancements in colorectal cancer research have led to an improvement in management and prognosis of the disease. Through the data of a specialized colorectal cancer Registry we aimed at analysing pathological staging and 5-year survival of all patients with malignancies of large bowel diagnosed between 1984 and 1997. Main objective was to ascertain whether or not we are making progress in the control of this common neoplasm. PATIENTS AND METHODS: During the 14-year period 1984-97, a total of 2,240 colorectal cancer patients were registered, for a crude incidence rate of 64.5 and 55.2/100,000/year in males and females, respectively Tumours were staged with "Tumour, Node, Metastasis" system, corresponding to Dukes' classification, into four main groups. Survival was assessed with Life Table analysis, and statistical significance--between various subgroups--evaluated with Log-Rank Test. RESULTS: Crude incidence rates of colorectal neoplasms showed minor fluctuations during initial period of registration, increasing sharply after 1990 mainly due to localized (stage I and II) lesions and, to a lesser degree, to stage III tumours. Number of advanced (stage IV and unstaged) malignancies remained virtually stable. When results were expressed as percent of total cases, the fraction of localized lesions increased from 39% in the biennium 1984-5 to 51.6% in 1986-97, and the proportion of advanced tumours fell from 39% to 21.6% (p for trend <0.001). As expected, 5-year survival was significantly (p<0.002) more favourable for individuals diagnosed in 1990-91 than for patients registered in 1984-89. CONCLUSIONS: In Northern Italy, incidence rates of colorectal carcinoma are rising. This trend is associated with a sharp increase of newly detected localized lesions and with a significant improvement of overall 5-year survival. The result may be attributed to several concomitant factors, such as: A] wider use of colonoscopy, B) increased education of patients, C) more attention given to symptoms.

The carnitine system and body composition.

Carnitine is a trimethylamine molecule that plays a unique role in cell energy metabolism. Mitochondrial betaoxidation of long-chain fatty acids, the major process by which fatty acids are oxidized, is ubiquitously dependent on carnitine. Control of mitochondrial beta-oxidation through carnitine adapts to differing requirements in different tissues. The physiological role of carnitine and its system in body composition is understood from insights into skeletal muscle metabolism, which converge into the metabolic heterogeneity of muscle fibers, and contractile properties that are correlated with phenotypes of resistance to fatigue. In skeletal muscle, the importance of the function of the carnitine system in the control and regulation of fuel partitioning not only relates to the metabolism of fatty acids and the capacity for fatty acid utilization, but also to systemic fat balance and insulin resistance. The carnitine system is shown to be determinant in insulin regulation of fat and glucose metabolic rate in skeletal muscle, this being critical in determining body composition and relevant raised levels of risk factors for cardiovascular disease, obesity, hypertension, and type 2 diabetes.

Concurrent inhibition of enzymatic activity and NF-Y-mediated transcription of Topoisomerase-IIα by bis-DemethoxyCurcumin in cancer cells.

Topoisomerases-IIα (TOP2A) enzyme is essential for cell viability due to its fundamental role in DNA metabolism and in chromatin organization during interphase and mitosis. TOP2A expression is finely regulated at the transcriptional level through the binding of the CCAAT-transcription factor NF-Y to its promoter. Overexpression and/or amplification of TOP2A have been observed in many types of cancers. For this reason, TOP2A is the target of the most widely successful drugs in cancer chemotherapy, such as TOP2A poisons, which stabilize TOP2A-DNA cleavage complexes and create DSBs, leading to chromosome damage and cell death. We previously reported that the Curcumin-derivative bis-DemethoxyCurcumin (bDMC) is an anti-proliferative agent that inhibits cell growth by concomitant G1/S and G2/M arrest. Here we showed that bDMC irreversibly induces DSBs in cancer cells, but not in normal cells, by targeting TOP2A activity and expression. TOP2A ablation by siRNA corroborates its contribution to apoptosis induced by bDMC. Short-term exposure to bDMC induces retention of TOP2A-DNA intermediates, while longer exposure inhibits TOP2A transcription by affecting expression and sub-cellular localization of NF-Y subunits. ChIP analysis highlighted reduced recruitment of NF-Y to TOP2A regulatory regions, concomitantly to histone deacetylation and decreased gene transcription. Our findings suggest that the dual activity of bDMC on TOP2A represents a novel therapeutic strategy to induce persistent apoptosis in cancer cells and identify NF-Y regulation as a promising approach in anti-cancer therapy.

Acetyl-L-carnitine increases artemin level and prevents neurotrophic factor alterations during neuropathy.

Damages to the nervous system are the primarily cause of neuropathy and chronic pain. Current pharmacological treatments for neuropathic pain are not able to prevent or revert morphological and molecular consequences of tissue injury. On the other hand, many neurotrophins, like nerve growth factor (NGF), paired off restorative effects with hyperalgesia. Interestingly, the glial cell line-derived neurotrophic factors GDNF and Artemin (ARTN) seem to support neuron survival and to normalize abnormal pain behaviour. In the present research protein levels of NGF, GDNF and ARTN were evaluated in a rat model of peripheral neuropathy, the chronic constriction injury (CCI). NGF was increased by CCI in the ipsilateral dorsal root ganglia (DRG), in the spinal cord and in the periaqueductal grey matter (PAG). On the contrary, ARTN was decreased bilaterally in DRG, spinal cord and PAG. GDNF levels decreased in ipsilateral DRG, whereas the constriction did not modify its expression in the central nervous system districts. Repeated treatments with the antihyperalgesic and neuroregenerative compound acetyl-l-carnitine (ALCAR; 100 mgkg(-1) i.p. twice daily for 15 days) was able to prevent the increase of NGF levels. In conditions of pain relief ALCAR normalized peripheral and central alterations of GDNF and ARTN levels. Characteristically, sham animals that underwent the same ALCAR treatment, showed increased levels of ARTN both in the DRG and in the spinal cord. These data offer a new point of view on the mechanism of the antihyperalgesic as well as the neuroprotective effect of ALCAR.

Differentiated thyroid carcinoma (DTC) in a young woman with Peutz-Jeghers syndrome: are these two conditions associated?

AIMS: Peutz-Jeghers Syndrome (PJS) is a rare dominantly inherited disease characterized by hamartomatous small bowel polyposis, mucocutaneous hyperpigmentation, and increased risk of cancer. Differentiated thyroid cancers (DTCs) present mainly as sporadic, but they may have also a familial component. We present a case of PJS in a caucasian 25 years-old woman, who developed a DTC. METHODS: The patient had a palpable nodule in the right side of the thyroid region and an endocrinological evaluation, including hormonal assays, neck ultrasound (US) and fine needle aspiration (FNAB) of the nodule was performed. RESULTS: US confirmed a single nodular lesion in the right thyroid lobe (14 mm). Cytological analysis at FNAB revealed a pattern compatible with papillary thyroid carcinoma. The histological analysis after total thyroidectomy confirmed the diagnosis of a Hurtle cell variant of papillary thyroid carcinoma, with follicular architecture. CONCLUSION: Even though rare, the association between PJS and DTC can be possible. In clinical practice it must be borne in mind that the wide spectrum of possible cancer diseases occurring in PJS could also include DTC, that the latter can occur earlier in life in PJS population and with a more aggressive histological pattern. Furthermore, in patients with PJS, US of the thyroid should be performed whenever thyroid disease is suspected at physical examination or based on patient's medical history. Due to lack of established data allowing for a real esteem of the association between PJS and DTC, US of the thyroid, should not be recommended as a routine screening for all subjects with PJS.

Epidemiology of colorectal cancer: the 21-year experience of a specialised registry.

UNLABELLED: Cancer registries can be viewed as one of the main strategies for improving our understanding of cancer, as they may reveal the importance of specific trends in cancer incidence and survival; in addition, the information obtained from the registries can be translated into preventive measures that might lead to a better control of neoplasms. A colorectal cancer registry was instituted in Northern Italy in 1984. The purpose of this study is to provide a description of the main findings observed in a 21-year period of continuous registration. RESULTS: A total of 3951 malignancies of the large bowel were registered in 3817 patients, for a crude incidence rate of 75.1/100 000/year in men and 59.0 in women. Overall incidence (crude and age-adjusted) of colorectal tumours increased remarkably throughout the registration period. This increase was mainly due to early (Stage I and II) tumours and to lesions with lymph nodal involvement (Stage III). There was a tendency over time towards a progressive increase of colonic tumours, whereas the fraction of rectal neoplasms tended to decline. Colorectal cancer-specific survival increased significantly over time in each of the main TNM/Dukes classes (p<0.006 and <0.001 for Stage II and III tumours). Finally, surgery for colorectal tumours showed a tendency towards large operations (colectomy and hemicolectomy), which was parallel to a definite improvement of pathological staging. CONCLUSIONS: Despite the increasing incidence of colorectal cancer, there are several reasons for cautious optimism. Most of the lesions are now diagnosed at an early stage, and this is associated with a significant increase of survival. The disease is undoubtedly cured better than in the past; the main challenge for future years is to achieve a sustained reduction of mortality for colorectal neoplasms.