Correction to: CCN2 inhibits lung cancer metastasis through promoting DAPK-dependent anoikis and inducing EGFR degradation.

Following publication of their article "CCN2 inhibits lung cancer metastasis through promoting DAPK-dependent anoikis and inducing EGFR degradation", the authors reported an error in Fig.6b. α-Tubulin image of rCCN2 treatment  (upper panel in CL1-5) only showed eight lanes, when there should be nine.

Frequent activating HRAS mutations in trichilemmoma.

BACKGROUND: Trichilemmoma is a benign follicular epithelial tumour exhibiting outer root sheath differentiation. It is associated with Cowden syndrome and naevus sebaceus (NS), but the pathogenesis of sporadic tumours is poorly understood. Recently, NS was found to be caused by postzygotic HRAS or KRAS mutations. OBJECTIVES: We sought to determine whether NS-related and NS-unrelated trichilemmomas harbour RAS mutations. METHODS: Formalin-fixed and paraffin-embedded blocks of 12 NS-related and 15 NS-unrelated trichilemmomas from 26 individuals were retrieved and analysed to determine the presence of mutations in exons 1 and 2 of the HRAS, KRAS and NRAS genes by polymerase chain reaction and direct sequencing. Mutational hotspots of the FGFR3 and PIK3CA genes were also analysed for NS-unrelated cases. RESULTS: Among the 27 cases, mutually exclusive HRAS c.37G>C and c.182A>G mutations were observed in 17 and three tumours, respectively. Of the 12 NS-related tumours, 11 (92%) harboured the HRAS c.37G>C substitution. Of the 15 sporadic tumours, nine (60%) harboured HRAS mutations, including six c.37G>C and three c.182A>G. An HRAS c.182A>G mutation was observed only in sporadic tumours. No mutations were observed in the other genes that were tested. CONCLUSIONS: The high frequency of HRAS activating mutations, including the c.182A>G substitution, which was rather rare in NS, suggests that most trichilemmomas are authentic neoplasms.

Autocrine/paracrine mechanism of interleukin-17B receptor promotes breast tumorigenesis through NF-κB-mediated antiapoptotic pathway.

Gain of function of membrane receptor was a good strategy exploited by cancer cells to benefit own growth and survival. Overexpression of HER2 has been found to serve as a target for developing trastuzumab to treat 20-25% of breast cancer. However, little or none of the other membrane receptor was found to be useful as a potential target for breast cancer treatment since then. Here, we showed that amplified signaling of interleukin-17 receptor B (IL-17RB) and its ligand IL-17B promoted tumorigenicity in breast cancer cells and impeded acinus formation in immortalized normal mammary epithelial cells. External signal transmitted through IL-17RB activated nuclear factor-κB to upregulate antiapoptotic factor Bcl-2 and induced etoposide resistance. Elevated expression of IL-17RB had a stronger correlation with poor prognosis than HER2 in breast cancer patients. Interestingly, breast cancer patients with high expression of IL-17RB and HER2 had the shortest survival rate. Depletion of IL-17RB in trastuzumab-resistant breast cancer cells significantly reduced their tumorigenic activity, suggesting that IL-17RB and HER2 have an independent role in breast carcinogenesis. Furthermore, treatment with antibodies specifically against IL-17RB or IL-17B effectively attenuated tumorigenicity of breast cancer cells. These results suggest that the amplified IL-17RB/IL-17B signaling pathways may serve as a therapeutic target for developing treatment to manage IL-17RB-associated breast cancer.

MiR-520h-mediated FOXC2 regulation is critical for inhibition of lung cancer progression by resveratrol.

Resveratrol, a phytochemical found in various plants and Chinese herbs, is associated with multiple tumor-suppressing activities, has been tested in clinical trials. However, the molecular mechanisms involved in resveratrol-mediated tumor suppressing activities are not yet completely defined. Here, we showed that treatment with resveratrol inhibited cell mobility through induction of the mesenchymal-epithelial transition (MET) in lung cancer cells. We also found that downregulation of FOXC2 (forkhead box C2) is critical for resveratrol-mediated suppression of tumor metastasis in an in vitro and in vivo models. We also identified a signal cascade, namely, resveratrol-∣miRNA-520h-∣PP2A/C-∣Akt → NF-κB → FOXC2, in which resveratrol inhibited the expression of FOXC2 through regulation of miRNA-520h-mediated signal cascade. This study identified a new miRNA-520h-related signal cascade involved in resveratrol-mediated tumor suppression activity and provide the clinical significances of miR-520h, PP2A/C and FOXC2 in lung cancer patients. Our results indicated a functional link between resveratrol-mediated miRNA-520h regulation and tumor suppressing ability, and provide a new insight into the role of resveratrol-induced molecular and epigenetic regulations in tumor suppression.

CCN2 inhibits lung cancer metastasis through promoting DAPK-dependent anoikis and inducing EGFR degradation.

CCN family protein 2 (CCN2), also known as connective tissue growth factor, is a secreting protein that modulates multiple cellular events. We previously demonstrated the metastasis-suppressive effect of CCN2 in lung cancer cells. In this study, we investigate the role of CCN2 in anoikis, a form of programmed cell death that is critical in suppressing cancer metastasis. CCN2 binds to the epidermal growth factor receptor (EGFR) and triggers ubiquitination by inhibiting the formation of the ß-pix/Cbl complex, resulting in the degradation of EGFR. Binding of CCN2 to EGFR suppresses the phosphorylation of c-Src and extracellular signal-regulated kinase but increases the expression of death-associated protein kinase, which leads to anoikis. Overall, our findings provide evidence validating the use of CCN2 as an anti-metastatic therapy in lung cancer patients, and prospect a potential therapeutic synergy between CCN2 and the anti-EGFR antibody for the treatment of lung cancer.

Immunostaining of glutamine synthetase is a sensitive and specific marker for diagnosing focal nodular hyperplasia in needle biopsy.

AIMS: Focal nodular hyperplasia (FNH) has characteristic histological features which may not be seen in needle biopsy specimens. We investigate the diagnostic role of glutamine synthetase (GS) in needle biopsy specimens. METHODS: Sixty-one hepatic tumours were categorised into 20 'definite' FNHs, 13 'probable' FNHs, and 28 cases without specific diagnosis. Needle biopsy specimens of 92 non-tumourous lesions, 25 well-differentiated hepatocellular carcinomas (WDHCCs), and 4 high-grade dysplastic nodules (HGDNs) and resection specimens of 10 macroregenerative nodules were also selected for immunohistochemical stain of GS for comparison. RESULTS: All 20 'definite' FNHs, nine 'probable' FNHs, and five cases without specific diagnosis expressed typical map-like staining pattern of GS. The demographic data of these five cases were similar to those of FNH. All cases of chronic hepatitis B and C, cirrhosis, macroregenerative nodule and peritumourous liver tissue showed normal pericentral/periseptal pattern. Fifteen of 25 WDHCCs and one HGDN showed diffuse pattern. Ten WDHCCs and two HGDNs showed negative staining. One HGDN showed mosaic pattern. CONCLUSIONS: Immunohistochemical staining of GS increases the diagnostic sensitivity of FNH in needle biopsy, especially in those without typical morphology. It also helps in differentiating FNH from other tumourous and non-tumourous lesions.

Connective tissue growth factor modulates oral squamous cell carcinoma invasion by activating a miR-504/FOXP1 signalling.

Connective tissue growth factor (CTGF) is a multi-functional secreted protein, and it has been shown either to promote or suppress tumor progression among different kinds of cancers. Here, we investigated the role of CTGF in oral squamous cell carcinoma (OSCC) invasion and metastasis. In five OSCC cell lines, endogenous CTGF negatively correlated with invasiveness. Exogenous CTGF protein or forced expression of CTGF gene in the oral cancer cell line SAS significantly decreased their invasive and migratory abilities. MicroRNA (miRNA) microarray analysis was performed in CTGF-overexpressed SAS cells (SAS/CTGF-M3) versus control cells to investigate the mechanism of CTGF-mediated inhibition of OSCC invasion. Among the miRNAs regulated by CTGF, miR-504 and miR-346 were the top two miRNAs downregulated in CTGF transfectants, and the result was confirmed by quantitative reverse transcriptase-PCR. Ectopic miR-504 increased migration and invasion in SAS/CTGF-M3, however, miR-346 did not have such impact on migration/invasion. Furthermore, we identified FOXP1, a member of forkhead transcription factors, as a target gene that takes part in the miR-504-induced cellular invasion. Knockdown of FOXP1 increased invasiveness in SAS/CTGF-M3, confirming the signal axis of CTGF/miR-504/FOXP1 in OSCC. Animal experiments showed that SAS/CTGF-M3-formed orthotopic tumors were associated with a lesser invasive phenotype than control cells. Expression of miR-504 in SAS/CTGF-M3 increased lymph node metastasis, and co-expression of FOXP1 in miR-504-transfected SAS/CTGF-M3 alleviated miR-504-induced metastasis. In OSCC samples, high CTGF was associated with a lower clinical stage and a better outcome. A reverse correlation between CTGF and miR-504, miR-504 and FOXP1, and a positive correlation between CTGF and FOXP1 were shown. Our study discovers a novel signal pathway involving the regulation of miRNA machinery by a secreted cytokine, which will be beneficial for developing therapeutic strategy against advanced OSCC.

Prognostic significance of insulin-like growth factor II mRNA-binding protein 3 expression in gastric adenocarcinoma.

BACKGROUND: Insulin-like growth factor II mRNA-binding protein (IMP) 3 is expressed in embryonic tissues and multiple cancers. The aim was to establish the prognostic value of IMP-3 expression in gastric adenocarcinoma. METHODS: IMP-3 expression in resected gastric adenocarcinomas was analysed by immunohistochemistry. RESULTS: IMP-3 was expressed in 183 (58.1 per cent) of 315 tumours. Expression was associated with older age (P < 0.001), larger tumour size (P = 0.009), deep tumour invasion (P < 0.001) and lymph node metastasis (P < 0.001). IMP-3-positive tumours were associated with poorer 5-year survival than negative tumours at all stages (stage I, 82 versus 97 per cent; stage II, 55 versus 78 per cent; stage III and IV, 11 versus 25 per cent; P = 0.005, P = 0.033 and P = 0.036 respectively). Multivariable analysis identified IMP-3 (hazard ratio (HR) 1.93), depth of tumour invasion (HR 3.69, 9.77 and 10.69 for pathological tumour stage (pT) 2, pT3 and pT4 respectively versus pT1), and lymph node metastasis (HR 1.57, 3.29 and 3.40 for pathological node stage (pN) 1, pN2 and pN3 respectively versus pN0) as independent prognostic factors. CONCLUSION: IMP-3 expression correlates with the metastatic potential of gastric adenocarcinoma and is an independent prognostic factor.

Frequent nuclear expression of beta-catenin protein but rare beta-catenin mutation in pulmonary sclerosing haemangioma.

BACKGROUND: Pulmonary sclerosing haemangioma (PSH) is an uncommon tumour that is composed of glandular/papillary lining cells and polygonal cells. The biological behaviour of this tumour has been investigated; however, the molecular pathogenesis of PSH remains unknown. AIMS: To characterise the role of the Wnt/beta-catenin pathway in the genesis of PSH. METHODS: 37 PSH samples were investigated immunohistochemically for detection of the beta-catenin protein and direct sequencing of exon 3 of the beta-catenin gene. RESULTS: Nuclear expression of beta-catenin was found in the lining component of 23 tumours (62%) and in the polygonal component of 11 tumours (30%). The expression of beta-catenin was stronger in the lining component, but weaker in the polygonal component. Interestingly, all the tumours with expression of beta-catenin in the polygonal component also expressed beta-catenin in the lining component. However, mutation of exon 3 of the beta-catenin gene was detected in only one tumour that expressed nuclear beta-catenin in lining and polygonal components. CONCLUSIONS: The Wnt/beta-catenin pathway is involved in the genesis of PSH, but mutation of exon 3 of the beta-catenin gene rarely contributes to the activation of the Wnt/beta-catenin pathway in PSH.

Brca1 heterozygous mice have shortened life span and are prone to ovarian tumorigenesis with haploinsufficiency upon ionizing irradiation.

BRCA1 mutation carriers have an 85% lifetime risk of breast cancer and 60% for ovarian cancer. BRCA1 facilitates DNA double-strand break repair, and dysfunction of BRCA1 leads to hypersensitivity to DNA damaging agents and consequently genomic instability of cells. In this communication, we have examined the tumor incidence and survival of Brca1 heterozygous female mice. Brca1 heterozygotes appear to have a shortened life span with 70% tumor incidence. Lymphoma, but not ovarian and mammary gland tumors, occurs commonly in these mice. After a whole-body exposure to ionizing radiation, Brca1 heterozygous mice have a 3-5-fold higher incidence specific to ovarian tumors, but not lymphoma, when compared with the Brca1+/+ mice. All the tumors from heterozygous mice examined retain the wild-type allele and the cancer cells express Brca1 protein, precluding the chromosomal mechanism for loss of heterozygosity of Brca1 locus. Although the manifestation of BRCA1 haploinsufficiency may be different between human and mouse, this study suggests that women carrying Brca1 mutations may be more prone to ovarian tumor formation after IR exposure than nonmutation carriers.

Stathmin overexpression cooperates with p53 mutation and osteopontin overexpression, and is associated with tumour progression, early recurrence, and poor prognosis in hepatocellular carcinoma.

Stathmin, a major microtubule-depolymerizing protein, is involved in cell cycle progression and cell motility. This study aimed to elucidate its role in the progression, early tumour recurrence (ETR), and prognosis of hepatocellular carcinoma (HCC). Stathmin mRNA was overexpressed in 88/156 (56%) resected, unifocal, primary HCCs, while p53 mutation was present in 72 (46%) and osteopontin mRNA overexpression in 79 (51%). Stathmin mRNA expression exhibited high concordance (93%) with protein expression in 107 cases examined by immunohistochemistry. Stathmin overexpression correlated with high alpha-fetoprotein (>200 ng/ml, p = 0.02), larger tumour size (>5 cm, p = 0.012), high tumour grade (p < 0.0002), high tumour stage (stage IIIA-IV) with vascular invasion and various degrees of intrahepatic metastasis (p < 1 x 10(-8)), ETR (p = 0.003), and lower 5-year survival (p = 0.0007). Stathmin protein expression was often more intense in the peripheral regions of tumour trabeculae, tumour borders, and portal vein tumour thrombi. Stathmin overexpression correlated with p53 mutation (p = 0.017) and osteopontin overexpression (p = 1 x 10(-8)), both of which were associated with vascular invasion (both p < 0.0001) and poorer prognosis (p < 0.0004 and p = 0.0004, respectively). Regardless of the status of p53 mutation or osteopontin expression, stathmin overexpression was associated with higher vascular invasion (all p < 0.0001). Approximately 90% of HCCs harbouring stathmin overexpression with concomitant p53 mutation or osteopontin overexpression exhibited vascular invasion, and hence the lowest 5-year survival, p = 0.00018 and p = 0.0009, respectively. However, we did not find that stathmin overexpression exerted prognostic impact independent of tumour stage. In conclusion, stathmin expression correlates with metastatic potential, is an important prognostic factor for HCC, and may serve as a useful marker to predict ETR.

Differential expression of glucocorticoid receptor in human breast tissues and related neoplasms.

Glucocorticoid receptor (GR) is a steroid hormone receptor that has been shown to play important roles in mammary development and differentiation, and has been implicated in breast tumourigenesis, but its precise biological significance in mammary pathophysiology remains unclear. In order to generate a comprehensive expression profile for GR in normal versus neoplastic breast tissues, GR expression was investigated in situ in 400 human breast tissue samples, comprising normal tissue and a range of benign, pre-invasive, and invasive lesions, using immunohistochemical assays. The novel expression of GR in myoepithelium, not observed in luminal epithelium, not only demonstrates expression patterns exclusive to the alpha form of oestrogen receptor and progesterone receptor and suggests distinctive functions between GR and these two important steroid hormone receptors in the breast, but may also indicate unique physiological and perhaps pathological roles for the myoepithelium in mediating the effects of glucocorticoid hormones in the breast. The strong expression of GR in metaplastic carcinomas (94.4%) and malignant phyllodes tumours (92.3%) suggests a pathogenetic role for GR, and implies that targeting GR in these tumours may have potential therapeutic application. However, studies on the roles of GR in mammary carcinogenesis should be interpreted with great caution, based on the lack of GR expression in cancer cells in the great majority (98.2%) of non-metaplastic carcinomas, which has gone unnoticed in previous studies. This marked discrepancy warrants a re-examination of the biological roles of GR in the pathophysiology of breast malignancy. The lack of methylation in the promoter region of the GR gene in all 118 non-metaplastic carcinomas, as demonstrated by methylation-specific PCR and bisulphite DNA sequencing analysis, indicates that methylation is less likely to play a role in the reduction of GR expression in non-metaplastic carcinoma of the breast.

Calreticulin expression in neuroblastoma--a novel independent prognostic factor.

BACKGROUND: Calreticulin (CRT), an endoplasmic reticulum protein, has been reported to be essential for the differentiation of neuroblastoma (NB) cells, suggesting that CRT may affect the tumor behavior of neuroblastoma. The aim of this study was to evaluate the association of clinicopathologic factors and patient survival with the expression of CRT in patients with NB. PATIENTS AND METHODS: Sixty-eight NBs were investigated by immunohistochemical staining against CRT, and were divided into positive and negative immunostaining groups. Correlations between calreticulin expression, various clinicopathologic and biologic factors, and patient survival were studied. In seven tumor samples, CRT mRNAs and proteins were evaluated with real-time PCR and western blot, respectively, and correlated with immunohistochemical findings. RESULTS: Among 68 NBs, 32 (47.1%) showed positive CRT expression. Positive CRT immunostaining strongly correlated with differentiated histologies, as well as known favorable prognostic factors such as detected from mass screening, younger age (< or =1 year) at diagnosis and early clinical stages, but inversely correlated with MYCN amplification. Kaplan-Meier analysis revealed that NB patients with CRT expression did have better survival. Multivariate analysis demonstrated CRT expression to be an independent prognostic factor. Moreover, CRT expression also predicted better survival in patients with advanced-stage NBs, and its absence predicted poorer survival in patients whose tumor had no MYCN amplification. The amount of CRT mRNAs and proteins in NB tumor samples tested correlated well with the immunohistochemical expressions. CONCLUSIONS: CRT expression correlates with the differentiation of NB and predicts favorable survival, thereby suggesting CRT to be a useful indicator for planning treatment of NB.

Microvessel density, cyclo-oxygenase 2 expression, K-ras mutation and p53 overexpression in colonic cancer.

BACKGROUND: Tumour angiogenesis, cyclo-oxygenase (COX) 2 expression, K-ras mutation and p53 overexpression are commonly involved in colorectal tumorigenesis, but their interrelationship and clinicopathological effects remain inconclusive. METHODS: Clinicopathological data from 114 consecutive patients with primary stage III colorectal cancer were evaluated prospectively. Microvessel density (MVD) of the tumour was defined by counting the number of microvessels in hotspots, visualized by immunocytochemical staining of endothelial CD34. K-ras mutation was analysed by the restriction enzyme cleavage method. COX-2 expression and p53 overexpression were determined by immunocytochemistry. RESULTS: Increased MVD in hotspots was significantly associated with COX-2 expression (P < 0.001), K-ras mutation (P = 0.007) and p53 overexpression (P = 0.006). COX-2 expression was not associated with either K-ras mutation or p53 overexpression. Clinicopathologically, greater MVD and COX-2 expression were significantly associated with vascular invasion of cancer cells (MVD, P = 0.027 and COX-2 expression, P = 0.006), but p53 overexpression and K-ras mutation were not. Multivariate analysis indicated that greater MVD (P = 0.002) and p53 overexpression (P = 0.016) were significant independent predictors of tumour recurrence, whereas COX-2 expression (P = 0.634) and K-ras mutation (P = 0.356) were not. CONCLUSION: Tumour angiogenesis may be associated with tumour metastasis and is significantly influenced by K-ras mutation, p53 overexpression and COX-2 expression in patients with colonic cancer.

Interferon-alpha reduces insulin resistance and beta-cell secretion in responders among patients with chronic hepatitis B and C.

This study aimed at elucidating the effects of interferon (IFN)-alpha on glucose metabolism in patients with chronic hepatitis B and C infections. Twenty-eight biopsy-proven patients with chronic hepatitis B (ten cases) and hepatitis C (18 cases) were given IFN-alpha for a total of 24 weeks. The patients received a 75 g oral glucose tolerance test (OGTT), glucagon stimulation test, tests for type 1 diabetes-related autoantibodies and an insulin suppression test before and after IFN-alpha therapy. Ten of the 28 patients responded to IFN-alpha therapy. Steady-state plasma glucose of the insulin suppression test decreased significantly in responders (13.32+/-1.48 (S.E.M.) vs 11.33+/-1.19 mmol/l, P=0.0501) but not in non-responders (12.29+/-1.24 vs 11.11+/-0.99 mmol/l, P=0.2110) immediately after completion of IFN-alpha treatment. In the oral glucose tolerance test, no significant difference was observed in plasma glucose in either responders (10.17+/-0.23 vs 10.03+/-0.22 mmol/l) or non-responders (10.11+/-0.22 vs 9.97+/-0.21 mmol/l) 3 Months after completion of IFN-alpha treatment. However, significant differences were noted in C-peptide in both responders (2.90+/-0.13 vs 2.20+/-0.09 nmol/l, P=0.0040) and non-responders (2.45+/-0.11 vs 2.22+/-0.08 nmol/l, P=0.0287) before vs after treatment. The changes of C-peptide in an OGTT between responders and non-responders were also significantly different (P=0.0028), with responders reporting a greater reduction in C-peptide. No case developed autoantibodies during the treatment. In patients who were successfully treated with IFN-alpha, insulin sensitivity improved and their plasma glucose stayed at the same level without secreting as much insulin from islet beta-cells.

Differentiation of ovarian mucinous carcinoma and metastatic colorectal adenocarcinoma by immunostaining with beta-catenin.

AIMS: To investigate whether localization of beta-catenin is helpful in differentiating primary ovarian mucinous carcinoma and colorectal adenocarcinoma metastatic to the ovary. Extra-ovarian cancers which metastasize to the ovaries, especially from colorectal adenocarcinoma, frequently mimic primary ovarian carcinomas, particularly endometrioid and mucinous types. Distinguishing primary ovarian carcinoma from metastatic colorectal carcinoma is important for both therapeutic and prognostic reasons. Even after thorough histological examination, metastatic colorectal adenocarcinomas are still often mistaken for primary ovarian adenocarcinomas. Although some tumour makers have been advocated and are helpful in most cases, sometimes the distinction between primary mucinous carcinoma and metastatic colorectal carcinoma remains a problem. Activation of Wnt signalling through mutations of APC or beta-catenin is a key event in the development of colorectal cancer. These mutations lead to nuclear localization of beta-catenin, which can be demonstrated immunohistochemically. METHODS AND RESULTS: Formalin-fixed paraffin-embedded specimens from 43 primary ovarian mucinous carcinomas and 23 metastatic colorectal adenocarcinomas were included in this study. Sections were immunostained with antibodies to beta-catenin, cytokeratin (CK)7, CK20 and carcinoembryonic antigen (CEA). Nuclear localization of beta-catenin was found in 83% (19/23) of metastatic colorectal cancers and 9% (4/43) of ovarian mucinous carcinomas. Ovarian mucinous carcinomas were usually positive for CK7 (34/43, 79%). For comparison, 40 non-mucinous carcinomas of the ovary and 42 metastatic adenocarcinomas from other organs were also immunostained with antibodies against beta-catenin. Although nuclear localization of beta-catenin was occasionally seen in non-mucinous carcinoma of the ovary and metastatic adenocarcinoma from other organs, such tumours were usually distinguishable by their clinicopathological picture and rarely raised diagnostic problems. CONCLUSIONS: Immunostaining of beta-catenin is a useful marker for differentiating between ovarian mucinous carcinoma and metastatic colorectal adenocarcinoma.

Clinicopathological and molecular biological features of colorectal cancer in patients less than 40 years of age.

BACKGROUND: The aim of the present study was to identify the clinicopathological and molecular biological characteristics of early-onset colorectal cancers. METHODS: The clinicopathological and molecular biological parameters of 138 consecutive patients with colorectal cancer aged less than 40 years were compared with those of 339 patients aged 60 years or more. RESULTS: The younger patients with colorectal cancer had more mucin-producing (14.5 versus 4.7 per cent; P < 0.001) and poorly differentiated (7.2 versus 3.3 per cent; P = 0.015) tumours, a higher incidence of synchronous (5.8 versus 1.2 per cent; P = 0.007) and metachronous (4.0 versus 0.6 per cent; P = 0.023) colorectal cancers, and more advanced tumour stage (P < 0.001) than older patients. The operative mortality rate was lower (0.7 versus 5.0 per cent; P = 0.026), and cancer-specific survival was similar (in stage I, II and III disease; P > 0.05) or better (in stage IV disease; 95 per cent confidence interval 22.50 to 28.41 versus 12.61 to 17.05 months; P < 0.001). There was a higher percentage of normal p53 expression (61.1 versus 46.8 per cent; P = 0.023) and high-frequency microsatellite instability (MSI-H) (29.4 versus 6.3 per cent; P < 0.001), and a similar family history of cancer (17.5 versus 14.2 per cent; P > 0.05), compared with older patients. CONCLUSION: Young patients with colorectal cancer have several distinct clinicopathological and molecular biological features. The mechanisms underlying the inconsistency between the presence of MSI-H and a family history of cancer in these early-onset colorectal cancers deserve further investigation.

Tumor angiogenesis and its possible role in intravasation of colorectal epithelial cells.

PURPOSE: To determine whether an increase in tumor angiogenesis facilitates intravasation of colorectal epithelial cells, we compared intratumoral microvessel counts with the presence of circulating colorectal epithelial cells in the portal venous blood from patients with colorectal carcinomas. EXPERIMENTAL DESIGN: Circulating colorectal epithelial cells were detected by a reverse transcription-PCR assay to amplify guanylyl cyclase C (GCC) transcripts. The extent of tumor vascularization was quantitatively assessed by immunohistochemical staining with anti-CD31 antibody. RESULTS: Colorectal epithelial cells (as measured by GCC mRNA expression) were detected in the portal venous blood in 30 of 58 patients (52%). The mean (+/- SD) microvessel count in the tumors from patients with expression of GCC mRNA in their portal venous blood was 82.74 +/- 24.97. The corresponding values in the tumors from patients without expression of GCC mRNA in portal venous blood was 65.96 +/- 19. For each 10-microvessel increase per x200 field, the risk of colorectal epithelial cell presence in the portal venous blood increased 1.52-fold (95% confidence interval, 1.19-2.12; P = 0.005). CONCLUSION: High intratumoral vessel count was noted to be a valuable factor for predicting the presence of colorectal epithelial cells in the portal venous blood.

Lymphoepithelioma-like cholangiocarcinoma: an Epstein-Barr virus-associated tumor.

Epstein-Barr virus (EBV) has been linked to carcinomas of several body sites, especially of the nasopharynx, salivary gland, lung, and stomach. We present five cases of lymphoepithelioma-like cholangiocarcinoma, including one that had been previously reported. Two patients were men and three were women. Their ages ranged from 42 to 66 years. Histologically, all five tumors were composed of variable proportions of undifferentiated epithelial cells and glandular components in a lymphocyte-rich stroma. EBV was detected in all five tumors by in situ hybridization for EBER-1 in both lymphoepithelioma-like carcinoma (LELC) and glandular parts, but not in 36 cases of cholangiocarcinoma without the LELC component. Taken together, these observations indicate that lymphoepithelioma-like cholangiocarcinoma is strongly linked to EBV. The LELC type of cholangiocarcinoma, like LELC of other body sites, may be more common in areas with endemic EBV infection.

Expression of mutant nuclear beta-catenin correlates with non-invasive hepatocellular carcinoma, absence of portal vein spread, and good prognosis.

beta-catenin has functions both in the cadherin-mediated cell adhesion system and in the signalling pathway that mediates dorsal axis patterning in the embryo; it has been shown to be aberrantly expressed or mutated in diverse types of human tumour, but the biological significance of this remains to be clarified. To elucidate the clinical implications of aberrant beta-catenin expression and the potential differences between mutant and wild-type beta-catenin protein expression in hepatocellular carcinoma (HCC), the protein expression was analysed by immunohistochemical staining, supplemented by the analysis of gene mutation. Among 372 unifocal primary HCCs, beta-catenin was detected in the tumour cell membrane alone in 272 tumours (group A) and also in the nuclei in 100 (group B). In group A, 148 tumours had decreased beta-catenin expression, but the reduction did not correlate with invasion or prognosis. When compared with group A, however, group B had significantly lower frequencies of hepatitis B surface antigen carrier (p=0.015), and alpha-fetoprotein elevation (p=0.0003), but more often had non-invasive HCC (p<0.001) and better survival (p=0.01). Nuclear beta-catenin expression strongly correlated with mutation of the gene (p<0.00001). In group B, HCC with mutant nuclear beta-catenin correlated positively with non-invasive (stage 1) tumour and inversely with portal vein tumour thrombi (stage 3 HCC), and had significantly better 5-year survival, p<0.001 and p<0.0003, respectively. These results suggest that beta-catenin mutation plays an important role in the tumourigenesis of a subset of HCC of good prognosis, and that mutant and wild-type nuclear beta-catenin proteins are not functionally equivalent.