Mucins and associated glycan signatures in colon adenoma-carcinoma sequence: Prospective pathological implication(s) for early diagnosis of colon cancer

Development of biomarkers that detect early stage resectable premalignant lesions of colon can provide critical aid in the prevention of colorectal cancer. Recent lines of evidence suggest the utility of mucin expression to predict malignant transformation of colon pre-neoplastic lesions. In this study, we investigated the combined expression of multiple mucins and mucin-associated glycans during the adenoma-carcinoma sequence of colon cancer progression. Further, we evaluated their applicability as markers for differentiating adenomas/adenocarcinomas from hyperplastic polyps. Immunohistochemical analyses performed on colon disease tissue microarrays revealed downregulation of MUC2 and MUC4 expression (p < 0.0001) while MUC1 and MUC5AC expressions were upregulated (p = 0.01) during adenoma-adenocarcinoma progression. Expression of MUC17 was downregulated in inflamed tissues compared to normal tissues, but its increased expression differentiated adenomas (p = 0.0028) and adenocarcinomas (p = 0.025) from inflammation. Glycan epitope-Tn/STn on MUC1 showed higher expression in hyperplastic polyps (p = 0.023), adenomas (p = 0.042) and adenocarcinomas (p = 0.0096) compared to normal tissues. Multivariate regression analyses indicated that a combination of MUC2, MUC5AC, and MUC17 could effectively discriminate adenoma-adenocarcinoma from hyperplastic polyps. Altogether, a combined analysis of altered mucins and mucin-associated glycans is a useful approach to distinguish premalignant/malignant lesions of colon from benign polyps.

Inhibition of hedgehog signaling improves the anti-carcinogenic effects of docetaxel in prostate cancer

The establishment of docetaxel-based chemotherapeutic treatments has improved the survival of castration-resistant prostate cancer (CRPC) patients. However, most patients develop resistance supporting the development of therapy. The current study was undertaken to establish the therapeutic benefit to target hedgehog signaling cascade using GDC-0449 to improve the efficacy of chemotherapeutic drug, docetaxel. Here, we show that the combination of GDC-0449 plus docetaxel inhibited the proliferation of WPE1-NB26 cells and PC3 cells via a blockade of G1 and G2M phases. The combined treatment significantly inhibited PC cell migration in vitro. Moreover, the apoptotic effect induced by GDC-0449 plus docetaxel on PC3 cells was mediated, at least partly, via the mitochondrial membrane depolarization, H₂O₂ production and caspase cascade activation. Interestingly, GDC-0449 was effective at inhibiting the prostasphere formation, inducing the prostasphere disintegration and apoptotic death of side population (SP) from PC3 cells and reversing the resistance of SP cells to docetaxel. In addition, GDC-0449 plus docetaxel also have shown a greater anti-tumoral growth inhibitory effect on PC3 cell xenografts. These findings support the use of the hedgehog inhibitor GDC-0449, which is currently in clinical trials, for improving the anticarcinogenic efficacy of docetaxel-based chemotherapeutic treatments against locally advanced, AI and metastatic PC.

MUC5AC interactions with integrin β4 enhances the migration of lung cancer cells through FAK signaling

MUC5AC is a secretory mucin aberrantly expressed in various cancers. In lung cancer, MUC5AC is overexpressed in both primary and metastatic lesions; however, its functional role is not well understood. The present study was aimed at evaluating mechanistic role of MUC5AC on metastasis of lung cancer cells. Clinically, the overexpression of MUC5AC was observed in lung cancer patient tissues and was associated with poor survival. In addition, the overexpression of Muc5ac was also observed in genetically engineered mouse lung adenocarcinoma tissues (Kras(G12D); Trp53(R172H/+); AdCre) in comparison with normal lung tissues. Our functional studies showed that MUC5AC knockdown resulted in significantly decreased migration in two lung cancer cell lines (A549 and H1437) as compared with scramble cells. Expression of integrins (α5, β1, β3, β4 and β5) was decreased in MUC5AC knockdown cells. As both integrins and MUC5AC have a von Willebrand factor domain, we assessed for possible interaction of MUC5AC and integrins in lung cancer cells. MUC5AC strongly interacted only with integrin β4. The co-localization of MUC5AC and integrin β4 was observed both in A549 lung cancer cells as well as genetically engineered mouse adenocarcinoma tissues. Activated integrins recruit focal adhesion kinase (FAK) that mediates metastatic downstream signaling pathways. Phosphorylation of FAK (Y397) was decreased in MUC5AC knockdown cells. MUC5AC/integrin β4/FAK-mediated lung cancer cell migration was confirmed through experiments utilizing a phosphorylation (Y397)-specific FAK inhibitor. In conclusion, overexpression of MUC5AC is a poor prognostic marker in lung cancer. MUC5AC interacts with integrin β4 that mediates phosphorylation of FAK at Y397 leading to lung cancer cell migration.

Novel pancreatic cancer cell lines derived from genetically engineered mouse models of spontaneous pancreatic adenocarcinoma: applications in diagnosis and therapy

Pancreatic cancer (PC) remains one of the most lethal human malignancies with poor prognosis. Despite all advances in preclinical research, there have not been significant translation of novel therapies into the clinics. The development of genetically engineered mouse (GEM) models that produce spontaneous pancreatic adenocarcinoma (PDAC) have increased our understanding of the pathogenesis of the disease. Although these PDAC mouse models are ideal for studying potential therapies and specific genetic mutations, there is a need for developing syngeneic cell lines from these models. In this study, we describe the successful establishment and characterization of three cell lines derived from two (PDAC) mouse models. The cell line UN-KC-6141 was derived from a pancreatic tumor of a Kras^G12D;Pdx1-Cre (KC) mouse at 50 weeks of age, whereas UN-KPC-960 and UN-KPC-961 cell lines were derived from pancreatic tumors of Kras^G12D;Trp53^R172H;Pdx1-Cre (KPC) mice at 17 weeks of age. The cancer mutations of these parent mice carried over to the daughter cell lines (i.e. Kras^G12D mutation was observed in all three cell lines while Trp53 mutation was observed only in KPC cell lines). The cell lines showed typical cobblestone epithelial morphology in culture, and unlike the previously established mouse PDAC cell line Panc02, expressed the ductal marker CK19. Furthermore, these cell lines expressed the epithelial-mesenchymal markers E-cadherin and N-cadherin, and also, Muc1 and Muc4 mucins. In addition, these cell lines were resistant to the chemotherapeutic drug Gemcitabine. Their implantation in vivo produced subcutaneous as well as tumors in the pancreas (orthotopic). The genetic mutations in these cell lines mimic the genetic compendium of human PDAC, which make them valuable models with a high potential of translational relevance for examining diagnostic markers and therapeutic drugs.

A population-based study of tumours of the renal pelvis and ureter: incidence, aetiology and histopathological findings

OBJECTIVE

Carcinoma of the renal pelvis and ureter are unusual tumours and our limited knowledge comes mainly from case reports and small series from large academic hospitals, as a rule without histopathological review. This study reports aetiological and demographical factors as well as clinicopathological findings of all patients in a large geographical region.

MATERIAL AND METHODS

All patients in western Sweden with a renal pelvic or ureteral tumour diagnosed between 1971 and 1998 (n = 930) were included. Untreated cases were not excluded. Demographic data and results of preoperative examinations were retrieved from the original clinical records. The histopathological slides were reviewed and tumour stage, grade, configuration, presence of carcinoma in situ and angiolymphatic invasion were determined.

RESULTS

The majority of patients (80%) had invasive or high-grade tumours. Carcinoma in situ was present among 30% of patients with non-invasive high-grade tumours. Angiolymphatic invasion (62%) and solid (non-papillary) growth pattern (84%) were very common among patients with stage T2-T4 tumours. Twenty-three women out of 138 (16.7%) with ureteral carcinoma had a history of abdominal radiotherapy for gynaecological cancer 22 years (median) earlier. Forty-one patients out of 930 (4.4%) had a history of abuse of phenacetin-containing analgesics.

CONCLUSIONS

This study demonstrates a very high incidence of high-grade upper tract tumours with carcinoma in situ, angiolymphatic invasion and solid (non-papillary) growth pattern, which underscores the malignant character of the disease. The possible association between pelvic radiotherapy and ureteral carcinoma warrants further study.

Abstract 4044: MUC4 knockdown induces cellular senescence in head and neck cancer cells

The limited effectiveness of therapy for patients with advanced stage Head and Neck Squamous Cell Carcinoma (HNSCC) or recurrent disease is a reflection of an incomplete understanding of the molecular basis of HNSCC pathogenesis. Cellular senescence is an extremely stable form of cell cycle arrest that limits the proliferation of damaged cells and may act as a natural barrier to cancer progression. MUC4, a high molecular weight glycoprotein, is overexpressed in many cancers and is implicated in cell proliferation, adhesion, anti-apoptosis, cell cycle regulation, migration and invasion of various carcinomas, but nothing is known about its clinical relevance and the mechanism through which it regulates cancer progression in HNSCC. Therefore, the present study was aimed to investigate clinical relevance and a potential role of MUC4 in cellular senescence in HNSCCs.

Using immunohistochemical analysis, we observed a significant up regulation of MUC4 in 79% (68/86) of HNSCC tissue samples compared to only 10% (1/10) of benign tissues. Further, we observed high expression of MUC4 in a majority of HNSCC cell lines tested. Knockdown (KD) of MUC4 with specific shRNA in HNSCC cells markedly decreased cell proliferation. The doubling time increased from 26 h to 36 h and 34 h to 42 h in MUC4 silenced UMSCC-1 and SCC-10B cells, respectively as compared to their control counterparts. MUC4 KD in UMSCC-1 and UMSCC-10B cells resulted in accumulation of cells at the G0/G1 phase with concomitant decrease in the expression of cell cycle regulating proteins like Cyclin-E and Cyclin-D1, and decrease in BrDU incorporation. More importantly, MUC4 KD resulted in the induction of cellular senescence in both cell lines as indicated by an increase in the number of flat, enlarged and senescence-associated β-galactosidase (SA-β-Gal) positive cells. Further,

MUC4 KD resulted in the inhibition of FAK signaling, and decreased motility and invasive behavior in both UMSCC-1 and UMSCC-10B cells. Mechanistic dissection of senescent response to MUC4 silencing indicated decreased acetylated histone enrichment at Cyclin-E/Cyclin-D1 promoters, leading to their downregulation. Further, both cell lines UMSCC-1 and UMSCC-10B underwent a P16 and P21 dependent cellular senescence in response to MUC4 KD that requires inactivation of Akt and ERK signaling. In conclusions, these findings suggest a novel role of MUC4 in regulating cellular senescence and provide evidence of the functional role of MUC4 in the proliferation, motility and invasion of HNSCC cells. Therefore, downregulation of MUC4 may be a promising therapeutic approach for Head and Neck cancer treatment.

Citation Format: Muzafar A. Macha, Satyanarayana Rachagani, Priya Pai, Maneesh Jain, Williams M. Lydiatt, Russell B. Smith, Sonny L. Johansson, Subodh M. Lele, Sham S. Kakar, Farghaly H. Ibrahim, John H. Lee. MUC4 knockdown induces cellular senescence in head and neck cancer cells. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4044. doi:10.1158/1538-7445.AM2013-4044

Mucin (Muc) expression during pancreatic cancer progression in spontaneous mouse model: potential implications for diagnosis and therapy

Background

Pancreatic cancer (PC) is a lethal malignancy primarily driven by activated Kras mutations and characterized by the deregulation of several genes including mucins. Previous studies on mucins have identified their significant role in both benign and malignant human diseases including PC progression and metastasis. However, the initiation of MUC expression during PC remains unknown because of lack of early stage tumor tissues from PC patients.

Methods

In the present study, we have evaluated stage specific expression patterns of mucins during mouse PC progression in (Kras^G12D;Pdx1-Cre (KC)) murine PC model from pancreatic intraepithelial neoplasia (PanIN) to pancreatic ductal adenocarcinoma (PDAC) by immunohistochemistry and quantitative real-time PCR.

Results

In agreement with previous studies on human PC, we observed a progressive increase in the expression of mucins particularly Muc1, Muc4 and Muc5AC in the pancreas of KC (as early as PanIN I) mice with advancement of PanIN lesions and PDAC both at mRNA and protein levels. Additionally, mucin expression correlated with the increased expression of inflammatory cytokines IFN-γ (p < 0.0062), CXCL1 (p < 0.00014) and CXCL2 (p < 0.08) in the pancreas of KC mice, which are known to induce mucin expression. Further, we also observed progressive increase in inflammation in pancreas of KC mice from 10 to 50 weeks of age as indicated by the increase in the macrophage infiltration. Overall, this study corroborates with previous human studies that indicated the aberrant overexpression of MUC1, MUC4 and MUC5AC mucins during the progression of PC.

Conclusions

Our study reinforces the potential utility of the KC murine model for determining the functional role of mucins in PC pathogenesis by crossing KC mice with corresponding mucin knockout mice and evaluating mucin based diagnostic and therapeutic approaches for lethal PC.

Reciprocal regulation of annexin A2 and EGFR with Her-2 in Her-2 negative and herceptin-resistant breast cancer

Alternative survival pathways are commonly seen to be upregulated upon inhibition of receptor tyrosine kinases (RTK), including Her-2. It is established that treatment with Herceptin leads to selective overexpression and activation of epidermal growth factor receptor (EGFR) and Src which further contributes to oncogenesis in Herceptin resistant and triple negative breast cancer (TNBC) patients. Here, we show a co-regulated upregulation in the expression of Annexin A2 (AnxA2), a known substrate of Src and one of the regulators of EGFR receptor endocytosis, in Herceptin resistant and Her-2 negative breast cancer. Immunohistochemical expression analysis revealed a reciprocal regulation between Her-2 and AnxA2 in breast cancer clinical samples as well as in cell lines as confirmed by protein and RNA analysis. The siRNA and Herceptin mediated downregulation/inhibition of Her-2 in Her-2 amplified cells induced AnxA2 expression and membrane translocation. In this study we report a possible involvement of AnxA2 in maintaining constitutively activated EGFR downstream signaling intermediates and hence in cell proliferation, migration and viability. This effect was consistent in Herceptin resistant JIMT-1 cells as well as in Her-2 negative breast cancer. The siRNA mediated AnxA2 downregulation leads to increased apoptosis, decreased cell viability and migration. Our studies further indicate the role of AnxA2 in EGFR-Src membrane bound signaling complex and ligand induced activation of downstream signaling pathways. Targeting this AnxA2 dependent positive regulation of EGFR signaling cascade may be of therapeutic value in Her-2 negative breast cancer.

Graviola: a novel promising natural-derived drug that inhibits tumorigenicity and metastasis of pancreatic cancer cells in vitro and in vivo through altering cell metabolism

Pancreatic tumors are resistant to conventional chemotherapies. The present study was aimed at evaluating the potential of a novel plant-derived product as a therapeutic agent for pancreatic cancer (PC). The effects of an extract from the tropical tree Annona Muricata, commonly known as Graviola, was evaluated for cytotoxicity, cell metabolism, cancer-associated protein/gene expression, tumorigenicity, and metastatic properties of PC cells. Our experiments revealed that Graviola induced necrosis of PC cells by inhibiting cellular metabolism. The expression of molecules related to hypoxia and glycolysis in PC cells (i.e. HIF-1α, NF-κB, GLUT1, GLUT4, HKII, and LDHA) were downregulated in the presence of the extract. In vitro functional assays further confirmed the inhibition of tumorigenic properties of PC cells. Overall, the compounds that are naturally present in a Graviola extract inhibited multiple signaling pathways that regulate metabolism, cell cycle, survival, and metastatic properties in PC cells. Collectively, alterations in these parameters led to a decrease in tumorigenicity and metastasis of orthotopically implanted pancreatic tumors, indicating promising characteristics of the natural product against this lethal disease.

Pathobiological implications of the expression of EGFR, pAkt, NF-κB and MIC-1 in prostate cancer stem cells and their progenies

The progression of prostate cancers (PCs) to locally invasive, androgen-independent and metastatic disease states is generally associated with treatment resistance and disease relapse. The present study was undertaken to establish the possibility of using a combination of specific oncogenic products, including epidermal growth factor receptor (EGFR), pAkt, nuclear factor-kappaB (NF-κB) and macrophage inhibitory cytokine-1 (MIC-1) as biomarkers and therapeutic targets for optimizing the management of patients with localized PC at earlier disease stages. The immunohistochemical and immunofluorescence data have revealed that the expression levels of EGFR, Ser⁴⁷³-pAkt, NF-κB p65 and MIC-1 proteins were significantly enhanced in the same subset of 76 cases of prostatic adenocarcinoma specimens during the disease progression and these biomarkers were expressed in a small subpopulation of CD133⁺ PC cells and the bulk tumor mass of CD133⁻ PC cells. Importantly, all of these biomarkers were also overexpressed in 80–100% of 30 PC metastasis bone tissue specimens. Moreover, the results have indicated that the EGF-EGFR signaling pathway can provide critical functions for the self-renewal of side population (SP) cells endowed with stem cell-like features from highly invasive WPE1-NB26 cells. Of therapeutic interest, the targeting of EGFR, pAkt, NF-κB or MIC-1 was also effective at suppressing the basal and EGF-promoted prostasphere formation by SP WPE1-NB26 cells, inducing disintegration of SP cell-derived prostaspheres and decreasing the viability of SP and non-SP WPE1-NB26 cell fractions. Also, the targeting of these oncogenic products induced the caspase-dependent apoptosis in chemoresistant SP WPE1-NB26 cells and enhanced their sensibility to the cytotoxic effects induced by docetaxel. These findings suggest that the combined use of EGFR, pAkt, NF-κB and/or MIC-1 may represent promising strategies for improving the accuracy of current diagnostic and prognostic methods and efficacy of treatments of PC patients in considering the disease heterogeneity, thereby preventing PC progression to metastatic and lethal disease states.

Small cell carcinoma of the renal pelvis and ureter: clinicopathologic and immunohistochemical features

CONTEXT

Small cell carcinoma (SCC) of the renal pelvis and/or ureter is very rare, with only case reports published in the literature.

OBJECTIVE

To describe the clinicopathologic and immunohistochemical findings in the largest series to date.

DESIGN

A review of a regional cancer registry identified 10 cases diagnosed as SCC from 930 patients with renal pelvic and/or ureteral cancer from 1971 to 1998. The original slides, demographics, treatment, and clinical outcome were reviewed. Representative sections were immunostained for AE1/AE3, cytokeratin 7, cytokeratin 20, CD56, synaptophysin, chromogranin, and thyroid transcription factor 1.

RESULTS

Of the 10 cases, 5 were pure SCC, 2 were mixed (SCC and urothelial carcinoma), 2 were reclassified as poorly differentiated squamous carcinoma, and 1 was reclassified as urothelial carcinoma. The patients with SCC had an age range of 50 to 80 years (median, 72 years) with a female to male ratio of 2.5:1. All patients had non-organ confined disease. Five of 7 patients died of disease; 4 of those 5 had been clinically followed (median survival, 23 months) and 1 was diagnosed at autopsy. The SCC cases revealed positive staining of the SCC component as follows: AE1/AE3 (7 of 7), CD56 (7 of 7), synaptophysin (6 of 7), thyroid transcription factor 1 (5 of 7), chromogranin (4 of 7), and cytokeratin 7 (1 of 7). None were positive for cytokeratin 20 (0 of 7).

CONCLUSIONS

SCC of the renal pelvis/ureter is seen in a predominately female population in Sweden, is clinically aggressive, and has poor survival when presenting at an advanced stage in patients only treated by surgery. An immunostain panel serves as a useful adjunct in classifying these tumors.

Upper urinary tract carcinoma in Lynch syndrome cases

PURPOSE

Patients with Lynch syndrome are much more likely to have generally rare upper urinary tract urothelial carcinoma but not bladder urothelial carcinoma. While the risk has been quantified, to our knowledge there is no description of how this population of patients with Lynch syndrome and upper urinary tract cancer differs from the general population with upper urinary tract cancer.

MATERIALS AND METHODS

We obtained retrospective data on a cohort of patients with Lynch syndrome from the Hereditary Cancer Center in Omaha, Nebraska and compared the data to those on a control general population from western Sweden. These data were supplemented by a new survey about exposure to known risk factors.

RESULTS

Of the patients with Lynch syndrome 91% had mutations in MSH2 rather than in MSH1 and 79% showed upper tract urothelial carcinoma a mean of 15.85 years after prior Lynch syndrome-type cancer. Median age at diagnosis was 62 years vs 70 in the general population (p <0.0001). Only half of our patients had a significant smoking history and the male-to-female ratio was 0.95. Of patients with Lynch syndrome 51% had urothelial carcinoma in the ureter while it occurred in the renal pelvis in 65% of the general population (p = 0.0013). Similar numbers of high grade tumors were found in the Lynch syndrome and general populations (88% and 74%, respectively, p = 0.1108).

CONCLUSIONS

Upper urinary tract tumors develop at a younger age and are more likely to be in the ureter with an almost equal gender ratio in patients with Lynch syndrome. It has high grade potential similar to that in the general population.

Neuroendocrine-type prostatic adenocarcinoma with microsatellite instability in a patient with lynch syndrome

Lynch syndrome is an autosomal-dominant cancer syndrome that can be identified with microsatellite instability molecular tests or immunohistochemical stains on pathologic material from patients who meet the Amsterdam Criteria II. The development of prostatic carcinoma in situ or invasive small cell carcinoma (SCC) of the prostate has not been previously reported in a patient with this syndrome. In this report, an 87-year-old White man with the Lynch syndrome had a prostate biopsy that revealed a mixed high-grade conventional adenocarcinoma and SCC of the prostate with high-grade prostatic intraepithelial neoplasia of the small cell neuroendocrine-type (HGPIN-NE), all showing MSH2 microsatellite instability and loss of MSH2 expression, a finding not previously published. These findings suggest that HGPIN-NE is a precursor of invasive SCC and also that prostatic SCC can develop in a patient with the Lynch syndrome.

Simple melanosis of the bladder: a rare entity

Simple melanosis of the bladder is an uncommon condition with fewer than 15 reported cases characterized by multifocal, diffuse melanin pigmentation of the urothelial mucosa. It is frequently associated with urinary incontinence or urgency. Histologically, melanin granules are present within urothelial cells or lamina propria macrophages with or without bland-appearing mucosal melanocytes. Although considered a benign entity, the rarity of the lesion warrants regular follow-up cystoscopic evaluation with biopsies to screen for the development of malignancy, especially malignant melanoma. This study presents a "typical" case with light, cytochemical, immunohistochemical, and ultrastructural characterization.

Abstract 3075: MUC4 mucin as a potential tumor suppressor in colon cancer

MUC4 is a heterodimeric large transmembrane mucin expressed by several normal epithelial tissues like testis, lungs and colon and is aberrantly over expressed by most human adenocarcinomas. MUC4 has been strongly implicated to play the role of an oncogene in the progression and metastasis of pancreatic, breast and ovarian cancers. On the other hand, previous reports indicating the loss of MUC4 expression in the progression of colon cancer was starkly in contrast to the role it plays in other cancers. Based on the previous studies, we hypothesized that loss of MUC4 as the tumor progresses might act as a prognostic indicator and MUC4 might act as a potential tumor suppressor in the colon cancer. In the present study, our aim was to investigate the functional significance of MUC4 in colon cancer progression. We performed immunohistochemistry on a tissue microarray comparing the expression levels of MUC4 among normal colon, adenoma, adenocarcinoma and metastatic adenocarcinoma. MUC4 immunoreactivity was highest in the normal colon tissue and significantly higher than tubular adenoma, non-metastatic and metastatic adenocarcinoma (p&lt;0.03) which confirmed the earlier findings. To evaluate the functional significance of MUC4, we stably over expressed MUC4 cDNA in HCT-15, a MUC4 non-expressing colon cancer cell line. Interestingly, the in vitro (growth kinetics, motility, invasion, colony forming) and in vivo (xenograft in nude mice) functional studies strongly support the role of MUC4 as a tumor suppressor in colon cancer. Further, mechanistic studies indicated that ectopic expression of MUC4 led to decreased activity of key intracellular signaling molecules like FAK, AKT and ERK. By regulating the levels of p-AKT, MUC4 expression led to growth arrest in S-phase which was mediated by the upregulation of cip/kip family of CDK inhibitors i.e. p21 and p27. Besides, overexpression of MUC4 led to a remarkable change from mesenchymal like (more triangular) phenotype to a more epithelioid (roundish) like phenotype confirmed by the phalloidin staining of the actin cytoskeleton. In conclusion, our results show for the first time the protective role MUC4 plays in colon cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 3075.

Urethral carcinoma and hyperplasia in male and female B6C3F1 mice treated with 3,3',4,4'-tetrachloroazobenzene (TCAB)

B6C3F1 mice chronically exposed to 3,3',4,4'-tetrachloroazobenzene (TCAB), a contaminant of dichloroaniline-derived herbicides, developed a number of neoplastic and nonneoplastic lesions, including carcinoma of the urinary tract. Groups of fifty male and fifty female B6C3F1 mice were exposed by gavage to TCAB at dose levels of 0, 3, 10, and 30 mg/kg five days a week for two years. Control animals received corn oil:acetone (99:1) vehicle. Decreased survival of male mice in the mid-dose group and of male and female mice in the high-dose groups was related mainly to the occurrence of urethral transitional cell (urothelial) carcinoma and resulting urinary obstruction. Increased urethral transitional cell carcinomas were seen in all treated male groups in a dose-related manner as well as in the females treated with 30 mg/kg TCAB. Administration of TCAB was also associated with increased transitional cell hyperplasia of the urethra. Most nonneoplastic lesions of the urogenital tract were considered secondary to local invasion and urinary obstruction by the urethral transitional cell carcinomas. The mechanism of tumor induction is uncertain, but the high frequency of tumors in the proximal urethra of male mice suggests that the neoplasms result from the exposure of a susceptible population of urothelial cells to a carcinogenic metabolite of TCAB.

MUC4 down-regulation reverses chemoresistance of pancreatic cancer stem/progenitor cells and their progenies

The present study was undertaken to estimate the therapeutic benefit to down-regulate the MUC4 mucin for reversing chemoresistance of pancreatic cancer (PC) stem/progenitor cells and their progenies. The results have revealed that MUC4 mucin is overexpressed in CD133(+) and CD133(-) pancreatic cells (PCs) detected in patient's adenocarcinoma tissues while no significant expression was seen in normal pancreatic tissues. The gain- and loss-of-function analyses have indicated that the overexpression of MUC4 in PC lines is associated with a higher resistance to the anti-proliferative, anti-invasive and apoptotic effects induced by gemcitabine. Importantly, the treatment of the MUC4-overexpressing CD18/HPAF-Src cells with gemcitabine resulted in an enrichment of the side population (SP) cells expressing CD133 while the total PC cells including non-SP cells detected in MUC4 knockdown CD18/HPAF-shMUC4 cells were responsive to the cytotoxic effects induced by gemcitabine. These data suggest that the MUC4 down-regulation may constitute a potential therapeutic strategy for improving the efficacy of gemcitabine to eradicate the total PC cell mass, and thereby preventing disease relapse.

Cytotoxic effects induced by docetaxel, gefitinib, and cyclopamine on side population and nonside population cell fractions from human invasive prostate cancer cells

The present study has been undertaken to establish the therapeutic benefit of cotargeting epidermal growth factor receptor (EGFR) and sonic hedgehog pathways by using gefitinib and cyclopamine, respectively, for improving the efficacy of the current chemotherapeutic drug docetaxel to counteract the prostate cancer progression from locally invasive to metastatic and recurrent disease stages. The data from immuofluorescence analyses revealed that EGFR/Tyr(1173)-pEGFR, sonic hedgehog ligand, smoothened coreceptor, and GLI-1 were colocalized with the CD133(+) stem cell-like marker in a small subpopulation of prostate cancer cells. These signaling molecules were also present in the bulk tumor mass of CD133(-) prostate cancer cells with a luminal phenotype detected in patient's adenocarcinoma tissues. Importantly, the results revealed that the CD133(+)/CD44(high)/AR(-/low) side population (SP) cell fraction endowed with a high self-renewal potential isolated from tumorigenic and invasive WPE1-NB26 cells by the Hoechst dye technique was insensitive to the current chemotherapeutic drug, docetaxel. In contrast, the docetaxel treatment induced significant antiproliferative and apoptotic effects on the CD133(-)/CD44(low)/AR(+) non-SP cell fraction isolated from the WPE1-NB26 cell line. Of therapeutic interest, the results have also indicated that combined docetaxel, gefitinib, and cyclopamine induced greater antiproliferative and apoptotic effects on SP and non-SP cell fractions isolated from WPE1-NB26 cells than individual drugs or two-drug combinations. Altogether, these observations suggest that EGFR and sonic hedgehog cascades may represent the potential therapeutic targets of great clinical interest to eradicate the total prostate cancer cell mass and improve the current docetaxel-based therapies against locally advanced and invasive prostate cancers, and thereby prevent metastases and disease relapse.

Completeness and correctness of registration of renal pelvic and ureteral cancer in the Swedish Cancer Registry

OBJECTIVE

To study the completeness and correctness of the Swedish Cancer Registry (SCR) for renal pelvic and ureteral carcinomas diagnosed in western Sweden.

MATERIAL AND METHODS

We performed a retrospective clinical and histopathological study of 939 patients in the SCR with a diagnosis of a renal pelvic or ureteral carcinoma between 1971 and 1998 and of 54 patients with a diagnosis of tumors in multiple locations in the urinary tract. In addition, we reviewed our earlier bladder cancer studies to assess whether patients with upper urinary tract tumors had been notified to the SCR.

RESULTS

There were 68 false-positive patients (7.2%) out of 939 in the SCR. The commonest diagnoses were other urological malignancies (n=46) and no malignancy at all (n=15). There were five false-positives (9.3%) out of 54 patients in the file with tumors in multiple locations. Twenty-eight patients with renal pelvic or ureteral carcinoma were identified in our earlier studies but not found in the SCR. Most discrepancies were attributable to inadequate or missing notification by the urologist and registration errors.

CONCLUSIONS

The completeness and correctness of the registration of renal pelvic and ureteral carcinomas are unsatisfactory but in line with registries for some other primary sites. The notification of upper urinary tract tumors among patients with a history of bladder cancer was poor, in particular in patients not treated with surgery. Improved communication between reporting sources and the registry is needed. Clinical and histopathological reviews seem necessary in studies based on the SCR.

Genome-wide expression profiling reveals transcriptomic variation and perturbed gene networks in androgen-dependent and androgen-independent prostate cancer cells

Previously, we have developed a unique in vitro LNCaP cell model, which includes androgen-dependent (LNCaP-C33), androgen-independent (LNCaP-C81) and an intermediate phenotype (LNCaP-C51) cell lines resembling the stages of prostate cancer progression to hormone independence. This model is advantageous in overcoming the heterogeneity associated with the prostate cancer up to a certain extent. We characterized and compared the gene expression profiles in LNCaP-C33 (androgen-dependent) and LNCaP-C81 (androgen-independent) cells using Affymetrix GeneChip array analyses. Multiple genes were identified exhibiting differential expression during androgen-independent progression. Among the important genes upregulated in androgen-independent cells were PCDH7, TPTE, TSPY, EPHA3, HGF, MET, EGF, TEM8, etc., whereas many candidate tumor suppressor genes (HTATIP2, CDKN2A, CDKN2B, CDKN1C, TP53, TP73, ICAM1, SOCS1/2, SPRY2, PPP2CA, PPP3CA, etc.) were decreased. Pathway prediction analysis identified important gene networks associated with growth-promoting and apoptotic signaling that were perturbed during androgen-independent progression. Further investigation of one of the genes, PPP2CA, which encodes the catalytic subunit of a serine phosphatase PP2A, a potent tumor suppressor, revealed that its expression was decreased in prostate cancer compared to adjacent normal/benign tissue. Furthermore, the downregulated expression of PPP2CA was significantly correlated with tumor stage and Gleason grade. Future studies on the identified differentially expressed genes and signaling pathways may be helpful in understanding the biology of prostate cancer progression and prove useful in developing novel prognostic biomarkers and therapy for androgen-refractory prostate cancer.

Quantitative fluorescence imaging analysis for cancer biomarker discovery: application to beta-catenin in archived prostate specimens

The surprising disparity between the number of protein-encoding genes ( approximately 30,000) in the human genome and the number of proteins ( approximately 300,000) in the human proteome has inspired the development of translational proteomics aimed at protein expression profiling of disease states. Translational proteomics, which offers the promise of early disease detection and individualized therapy, requires new methods for the analysis of clinical specimens. We have developed quantitative fluorescence imaging analysis (QFIA) for accurate, reproducible quantification of proteins in slide-mounted tissues. The method has been validated for the analysis of beta-catenin in archived prostate specimens fixed in formalin. QFIA takes advantage of the linearity of fluorescence antibody signaling for tissue epitope content, a feature validated for beta-catenin in methacarn-fixed prostate specimens analyzed by reverse-phase protein array analysis and QFIA (r = 0.97). QFIA of beta-catenin in formaldehyde-fixed tissues correlated directly with beta-catenin content (r = 0.86). Application of QFIA in a cross-sectional study of biopsies from 42 prostate cancer (PC) cases and 42 matched controls identified beta-catenin as a potential field marker for PC. Receiver operating characteristic plots revealed that beta-catenin expression in the normal-appearing acini of cancerous glands identified 42% (95% confidence intervals, 26-57%) of cancer cases, with 88% (95% confidence intervals, 80-96%) specificity. The marker may contribute to a PC biomarker panel. In conclusion, we report the development and validation of a new method for fluorescence quantification of proteins in archived tissues and its application to archived specimens for an evaluation of beta-catenin expression as a biomarker for PC.

Combined targeting of epidermal growth factor receptor and hedgehog signaling by gefitinib and cyclopamine cooperatively improves the cytotoxic effects of docetaxel on metastatic prostate cancer cells

The epidermal growth factor receptor (EGFR) and hedgehog cascades provide a critical role in prostate cancer progression and contribute to the resistance to clinical therapies and disease relapse. Therefore, we evaluated, for the first time, the antiproliferative and cytotoxic effects induced by a combination of selective inhibitors of EGFR tyrosine kinase and smoothened hedgehog signaling element, gefitinib and cyclopamine, with a current chemotherapeutic drug used in the clinics, docetaxel, on some metastatic prostate cancer cell lines. Immunohistochemical analyses revealed that sonic hedgehog (SHH) expression was enhanced in 39% of primary prostatic adenocarcinomas (Gleason scores 4-10) compared with the corresponding normal tissues of the same prostate gland from 32 prostate cancer patients. The confocal microscopy and Western blot analyses have also indicated the high expression levels of SHH and EGFR in metastatic LNCaP, DU145, and PC3 cells. Moreover, the results revealed that the drugs, alone or in combination, at lower concentrations inhibited the growth of EGF plus SHH-stimulated and serum-stimulated androgen-responsive LNCaP-C33 and androgen-independent LNCaP-C81, DU145, and PC3 cells. Importantly, the combined docetaxel, gefitinib, and cyclopamine also caused a higher rate of apoptotic death of prostate cancer cells compared with individual agents. The cytotoxic effects induced by these drugs in PC3 cells seem to be mediated in part through the cellular ceramide production and activation of caspase cascades via a mitochondrial pathway and the release of cytochrome c into the cytosol. Additionally, the combined agents were more effective at suppressing the invasiveness of PC3 cells through Matrigel in vitro than the single drugs. These findings indicate that the combined use of inhibitors of EGF-EGFR and hedgehog signaling with docetaxel could represent a more promising strategy for treatment in patients with metastatic and androgen-independent prostate cancer.

Clinical Significance of Benign Glands at Surgical Margins in Robotic Radical Prostatectomy Specimens

OBJECTIVES

Completion of robotic radical prostatectomy compared with conventional open retropubic radical prostatectomy can result in different alterations in the prostatectomy specimens. One difference appears to be an increased incidence of benign glands at the margins, which has been associated with an increase in postoperative prostatic-specific antigen (PSA) levels. We compared the frequency and clinical significance of benign prostate glands at the surgical margins in radical prostatectomy specimens obtained by robotic versus open retropubic prostatectomy.

METHODS

We reviewed 38 consecutive prostatectomy specimens from patients with biopsy-proven prostate cancer. Of these 38 specimens, 25 (65%) were obtained by robotic resection and 13 (35%) by open retropubic prostatectomy. Each case was analyzed for Gleason score, pathologic stage, including margin status, and the presence or absence of benign glands at the surgical margin. The study endpoint was the postoperative serum PSA level.

RESULTS

A significantly greater incidence (P = 0.035) of benign glands at the surgical margins was found within the robotic group compared with the open retropubic prostatectomy group (54% versus 15%). With a median follow-up of 12.5 months for the robotic group and 24.5 months for the robotic prostatectomy group, only 2 patients, who also had had positive surgical margins, had a continued and persistent increase in the postoperative PSA level after an initial nadir.

CONCLUSIONS

The early clinical follow-up data of our study have suggested that patients undergoing robotic radical prostatectomy with negative surgical margins achieve a PSA nadir of less than 0.1 ng/mL, irrespective of the presence or absence of benign prostatic tissue at the surgical margins.

Squamous cell carcinoma of the renal pelvis and ureter: incidence, symptoms, treatment and outcome

PURPOSE

Squamous cell carcinomas of the renal pelvis and ureter are rare. We report a large series of patients and compare it to patients with urothelial carcinoma.

MATERIALS AND METHODS

The initial material was comprised of 808 patients with renal pelvis or ureteral cancer. A review of the histopathological material and clinical records was performed.

RESULTS

Only 2 (4%) of 65 patients with squamous cell carcinoma had stage pTa/pT1/pT2 tumors compared to 460 (62%) of 743 patients with urothelial carcinoma. Median survival was much shorter for surgically treated patients with squamous cell carcinoma compared to those with urothelial carcinoma (7 vs 50 months). However, there was no significant difference in the disease specific 5-year survival rate between patients with squamous cell carcinoma and urothelial carcinoma in the same disease stage. Vascular invasion, microscopic solid tumor pattern and large tumor size had negative prognostic significance in multivariate analyses. Histopathological tumor type (squamous cell carcinoma or urothelial carcinoma) had no prognostic significance.

CONCLUSIONS

The prognosis for squamous cell carcinoma is poor, but stage for stage the prognosis is not different between patients with urothelial carcinoma and squamous cell carcinoma of the renal pelvis and ureter. It can be presumed that high stage squamous cell carcinoma and urothelial carcinoma become symptomatic first at a time when the tumors already are large, deeply invasive and most often incurable. New treatment modalities are urgently needed to improve the poor prognosis in patients with advanced stage squamous cell carcinoma and urothelial carcinoma of the upper urinary tract.

Prostate-derived factor as a paracrine and autocrine factor for the proliferation of androgen receptor-positive human prostate cancer cells

BACKGROUND

The expression of prostate-derived factor (PDF) is significantly elevated in human prostate tumors. We investigate the functional role and signaling of PDF in androgen receptor (AR)-positive human prostate cancer cells.

METHODS

Transient or stable expression of PDF by cDNA transfection, antisense-mediated gene silencing, media conditioned by PDF-elevated cells, and antibody (Ab) neutralization were employed.

RESULTS

Elevated endogenous and exogenous expression of PDF and treatment of PDF-enriched media were associated with increased proliferation and clonogenic growth of the cells. On the contrary, knockdown of PDF or addition of PDF neutralizing Ab resulted in diminished proliferation and reduced anchorage-independent growth. Further, ERK1/2 and p90RSK, but not Smad2/3, were activated in PDF-elevated cells as well as in cells treated with PDF-enriched media, while inhibition of ERK1/2 decreased the growth of those cells.

CONCLUSION

PDF promotes AR-positive prostate tumor progression through upregulating cell proliferation via ERK1/2 signal pathway.

Impact of diagnostic and treatment delay on survival in patients with renal pelvic and ureteral cancer

OBJECTIVE

To investigate the relationships between diagnostic and treatment delay and tumour stage and survival among patients with malignant tumours in the renal pelvis and ureter.

MATERIAL AND METHODS

A clinical and histopathological review was performed on 943 patients with a primary malignant tumour in the renal pelvis and ureter. We selected 394 patients who had macrohaematuria as an initial symptom, had no previous history of bladder cancer, had undergone surgery and had adequate follow-up. We performed uni- and multivariate analyses of prognostic factors for disease-specific survival.

RESULTS

The median number of days between the first occurrence of macrohaematuria and surgery was 83.5 days (range 4-1770 days). Patients with advanced tumours had the shortest median delay. Advanced tumour stage, a solid growth pattern and vascular invasion were of prognostic importance for disease-specific survival in the multivariate analysis, but diagnostic and treatment delay were not.

CONCLUSIONS

Although the delay was unacceptably long it still had no impact on survival, probably because macroscopic haematuria is a late symptom, in particular in high-grade tumours. New screening methods for the early detection of cancer and new treatment modalities are needed to improve the poor prognosis in stage pT3-pT4 tumours.

Novel combination therapy against metastatic and androgen-independent prostate cancer by using gefitinib, tamoxifen and etoposide

In this study, we evaluated, for the first time, the antiproliferative and cytotoxic effects induced by a combination of a selective epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor, gefitinib, with other chemotherapeutic drugs including estrogen receptor-beta (ER-beta) antagonist (tamoxifen) and topoisomerase II inhibitor (etoposide) on some metastatic prostate cancer (PC) cell lines. Immunohistochemial analyses revealed that EGFR expression was enhanced in 38% of primary prostatic adenocarcinomas (Gleason scores 4-10) as compared to the corresponding normal tissues of the same prostate gland from 32 PC patients. The RT-PCR and Western blot data have also indicated the higher expression levels of EGFR and ER-beta transcripts and proteins in metastatic LNCaP, DU145 and PC3 cells relative to nonmalignant normal prostate cells. Moreover, the results from MTT and FACS analyses revealed that the drugs, alone or in combination at lower concentrations, inhibited the growth of 17beta-estradiol (E2) plus EGF and serum-stimulated androgen-responsive LNCaP-C33 and androgen-independent LNCaP-C81, DU145 and PC3 cells. Importantly, the combined gefitinib, tamoxifen and etoposide also caused a higher rate of apoptotic death of PC cells as compared to single agents. The cytotoxic effects induced by these drugs in PC3 cells appear to be mediated through the accumulation of cellular ceramide and activation of caspase cascades via a mitochondrial pathway. These findings indicate that the combined use of inhibitors of EGF-EGFR and E2-ER-beta signaling with etoposide, which act by increasing the cellular ceramide levels and caspase activity, represents a promising strategy for a more effective treatment of metastatic PC forms.

Expression of TAG-72 in ovarian cancer and its correlation with tumor stage and patient prognosis

Tumor associated glycoprotein-72 (TAG-72), a pancarcinoma antigen, was initially identified in cancer tissues by its immunoreactivity to a monoclonal antibody B72.3. In this study, we have analyzed the expression and localization profiles of TAG-72 in ovarian cancer tissue samples of different stages and histological subtypes by immunohistochemistry using a second generation high affinity monoclonal antibody CC49. We have also studied the expression of TAG-72 in ovarian cancer cell lines by confocal microscopy and immunoblot analyses. A correlation between TAG-72 expression and localization with patients' prognosis was also analyzed using Kaplan-Meier analysis. Eighty eight percent of the ovarian cancer tissue samples (n=43) showed immunoreactivity with CC49 antibody. The expression of TAG-72 in advanced stage cancer tissues (mean composite score=3.7) was significantly higher (p=0.035) compared to the early stage tumors (mean composite score=2.3). However, no significant correlation of TAG-72 was observed with histological tumor types. A marginal correlation of TAG-72 staining with patients' survival was observed. Interestingly, the membrane localization of TAG-72 in tumors was significantly (p=0.0082) associated to the poor clinical outcome, while cytoplasmic staining was correlated significantly to a better prognosis (p=0.0051). Immunoblot analysis demonstrated the expression of TAG-72 in three ovarian cancer cell lines (OVCAR3, SB247 and COV362.4). In conclusion, the tumor-specific expression of TAG-72 and its association with disease stage indicate its potential as a marker for effective disease management and targeted cancer therapy.

Aberrant expression of MUC4 in ovarian carcinoma: diagnostic significance alone and in combination with MUC1 and MUC16 (CA125)

Mucins are being implicated in diagnosis, prognosis, and as therapeutic targets due to their aberrant expression in a variety of carcinomas. Here, we have analyzed the expression of MUC4 and have compared its potential usefulness in early detection and prognosis of ovarian carcinoma alone and in combination with other mucin antigens, MUC1 and MUC16. Clinical significance of the differential mucin expression was evaluated by grouping the tumor samples in early (stage I and II) and advanced (stage III and IV) stage cases and histological subtypes (serous, mucinous, endometrioid and clear cell). Correlation of these mucins with patient's survival (n=63) was determined by Kaplan-Meier analysis in order to predict their prognostic value. MUC4 showed significant overexpression in tumor cases (P<0.0001) with highest incidence (92.0%) among all three mucins. A significant overexpression of MUC1 (P<0.018) and MUC16 (P<0.0001) was also observed in 83.0 and 79.0% of tumor samples, respectively. Notably, MUC4 expression was significantly higher (P</=0.004) compared to both MUC1 and MUC16 in early-stage ovarian tumor samples with 100% incidence. In advanced stage ovarian tumors, all the mucins displayed overall comparable expression, nonetheless, MUC4 had highest prevalence (88.0%) compared to MUC1 (84.0%) and MUC16 (81.0%). A combined panel of MUC4 with MUC16 detected 100% of the late-stage tumor cases without compromising the specificity. Among histological subtypes, only MUC4 displayed 100% (n=5) sensitivity in mucinous ovarian tumors, while MUC1 and MUC16 detected 40 and 20% cases, respectively. The expression of MUC4, however, did not significantly correlate with the survival of the ovarian cancer patient, while a significant correlation of MUC16 with poor prognosis was observed. In conclusion, our study demonstrates that MUC4 could be a potential candidate marker for early diagnosis of epithelial ovarian carcinoma and can be utilized in combination with MUC16 to achieve greater sensitivity for the detection of late-stage tumors.

Use of a multitarget fluorescence in situ hybridization assay to diagnose bladder cancer in patients with hematuria

PURPOSE

We evaluated the multitarget UroVysion fluorescence in situ hybridization assay for the diagnosis of bladder cancer in patients with hematuria and no history of bladder cancer.

MATERIALS AND METHODS

A multicenter, blinded trial was performed to compare the sensitivity of the fluorescence in situ hybridization assay to that of voided cytology in patients with gross or microscopic hematuria. Confirmation of hematuria was required. Voided urine was sent to a central laboratory for each study before cystoscopy. Suspicious lesions on cystoscopy were biopsied or resected. A centrally reviewed histopathological interpretation was used to confirm cancer and assign grade and stage.

RESULTS

A total of 497 patients were enrolled at 23 centers and in 473 (95.2%) fluorescence in situ hybridization and cytology results were interpretable. Bladder cancer was diagnosed histologically in 50 patients (10.1%) and ureteral cancer was diagnosed in 1. Fluorescence in situ hybridization assay detected 69% of cases and cytology detected 38% (95% CI 25 to 52). When low grade, low stage (TaG1) tumors were excluded, fluorescence in situ hybridization detected 25 of 30 cancers (84%), while cytology detected only 15 (50%). Of 265 current or past smokers with hematuria and positive fluorescence in situ hybridization assay findings bladder cancer was detected in 65% with a history of greater than 40 pack-years compared to 13.6% to 24.2% in those with no, less than a 20 or a 20 to 40-pack-year smoking history.

CONCLUSIONS

The UroVysion fluorescence in situ hybridization assay is significantly more sensitive than voided cytology for detecting bladder cancer in patients evaluated for gross or microscopic hematuria for all grades and stages. Based on these data UroVysion was approved by the Food and Drug Administration for use in patients with hematuria.

Tumour-associated macrophage infiltration, neovascularization and aggressiveness in malignant melanoma: role of monocyte chemotactic protein-1 and vascular endothelial growth factor-A

The objective of this study was to evaluate the role of tumour-associated macrophages (TAMs) in malignant melanoma progression, invasion and angiogenesis. We examined the levels of macrophage infiltration and monocyte chemotactic protein-1 (MCP-1), neovascularization and vascular endothelial growth factor-A (VEGF-A) in different Clark's level melanomas with varying thicknesses and metastases. The level of TAM density was significantly higher in thick (>0.75 mm) than thin (<or=0.75 mm) melanomas, and positively correlated with melanoma invasiveness and metastasis. In contrast, MCP-1 expression was significantly lower in thick (>0.75 mm) than thin (<or=0.75 mm) melanomas and negatively correlated with melanoma aggressiveness and invasion. We did not observe any significant difference in the levels of neovascularization between thin and thick melanomas, and no correlation with VEGF-A expression, TAM density or melanoma aggressiveness and invasion. Interestingly, levels of VEGF-A were significantly higher in metastatic melanoma than in thick melanoma. In addition, we observed lower levels of MCP-1 messenger RNA (mRNA) expression in more aggressive melanomas and in cell lines with higher metastatic potential. In summary, our data suggest a distinct pattern of TAM infiltration, MCP-1 expression, neovascularization and VEGF-A expression during human melanoma progression, and a complex interaction between TAMs and melanoma cells in the regulation of melanoma progression, angiogenesis and metastasis.

Distinct expression of CXCL8 and its receptors CXCR1 and CXCR2 and their association with vessel density and aggressiveness in malignant melanoma

We examined the expression of CXCL8 (interleukin-8), its receptors, CXCR1 and CXCR2, and vessel density in human melanoma by immunohistochemical analysis of tumors from different Clark levels, depths, and thicknesses. Expression of CXCL8 and CXCR2 was lower in Clark level I and II specimens than in level III through V specimens and metastases. CXCR1 expression was observed ubiquitously in the majority of human melanoma tumor specimens irrespective of disease state, with the highest intensity in Clark level III specimens. We observed a significant difference in CXCL8 and CXCR2 expression between thin (<or=0.75 mm) and thick (>0.75 mm) melanomas and between thin and metastatic lesions. Positive correlations were observed between Clark level and CXCL8 or CXCR2 and between thickness and CXCR2 expression. We found no correlation between vessel density and Clark level or thickness. Our data suggest that expression of CXCL8 and CXCR2 contributes to aggressive growth and metastasis in human malignant melanoma. Consistent with the transition from radial to vertical growth phase melanoma, expression of CXCL8 and its receptor, CXCR2, may be key in the switch to an aggressive, more metastatic phenotype.

Aberrant expression of transmembrane mucins, MUC1 and MUC4, in human prostate carcinomas

BACKGROUND

Mucins are considered important markers for early diagnosis and targeted therapy due to their aberrant and unique expression pattern during malignant progression of carcinomas. Recent findings have provided substantial evidence for the involvement of transmembrane mucins, MUC1 and MUC4, in altered cell signaling, tumor growth, and metastasis.

METHODS

Immunohistochemical analyses were performed on prostate tumor tissues for expression profiling of the two transmembrane mucins, MUC1 and MUC4. In cancer cell lines, the expression was studied by RT-PCR and immunoblot analyses. Cells were treated with DNA-methylase and histone-deacetylase inhibitors to examine the implication of epigenetic mechanism(s) in MUC4 regulation.

RESULTS

The expression of MUC4 was significantly down regulated in prostate cancer tissues (n=38, P=0.0026) compared to normal/benign prostatic hyperplastic regions. A faint to moderate staining was observed in 26.3% cases of cancer, while 84.2% cases of adjacent normal were positive for MUC4 with moderate to strong staining in most cases. Similar observations were made in immortalized normal prostate epithelial and cancer cell lines. MUC1 also showed a reduced expression in prostate tumor tissues; however, its expression was comparable in all normal prostate epithelial and cancer cell lines. Interestingly, we also found that epigenetic mechanism(s) might be implicated in MUC4 gene silencing.

CONCLUSIONS

Our data suggest that MUC4 downregulation may be of significance for diagnostic applications in prostate cancer.

Aberrant expression of E-cadherin and beta-catenin in human prostate cancer

Cadherin-catenin complexes play a key role in embryonic development, and are associated with carcinogenesis and metastasis. We studied the expression of the major members of the family, including E-cadherin and beta-catenin in prostate cancer (PC), and correlated with Gleason grade and pathologic stage. Immunohistochemistry was performed on serial sections of paraffinized radical prostatectomy specimens to evaluate E-cadherin (n = 16) and beta-catenin (n = 17) expression using heat induced epitope retrieval. Benign appearing prostate epithelium was used as an internal control in each specimen. Two pathologists independently reviewed and scored the intensity and extent of immunostaining using a semiquantitative scale. The Mantel-Haenszel method, stratified by reviewer, was used to test for an association among Gleason score, pathologic stage, and the expression of E-cadherin or beta-catenin in PC. Gleason grade > or =7 cancers showed significantly lower expression of E-cadherin and beta-catenin compared to Gleason grade < 7 PC, P = 0.015 and 0.025, respectively. In addition, beta-catenin was down regulated in 4 of 5 (80%) specimens with identifiable high-grade prostatic intraepithelial neoplasia and had demonstrable nuclear staining in higher grade PC (P = 0.0001). However, E-cadherin and beta-catenin membranous or nuclear expressions were not significantly associated with final pathologic stage of the specimens (P values >0.05). Overall, the expression of E-cadherin and beta-catenin is significantly down regulated in PC compared to surrounding benign appearing prostate, which correlates with increasing Gleason grade. Furthermore, nuclear localization of beta-catenin in high grade PC may be a useful biomarker for aggressive PC.

Micropapillary Carcinoma of the Renal Pelvis and Ureter

PURPOSE

MPC located in the upper urinary tract is rare with only 2 cases reported to date. We report clinical and histopathological data on 26 patients to increase the knowledge of this rare entity.

MATERIALS AND METHODS

A clinical and histopathological review was performed in 943 patients with a neoplasm in the renal pelvis or ureter, diagnosed between 1971 and 1998. We identified 26 patients with MPC. No patients were alive at the end of the study.

RESULTS

Of the patients 11 had greater than 50% MPC and 15 had focal MPC (at least 10%). The incidence was 2.8%. Median patient age at diagnosis was 69 years (range 54 to 88) and the male-to-female ratio was 17:9. All except 4 patients had stage T3 disease or higher. Carcinoma in situ was identified in 64% of cases and vascular invasion was present in 81%. A total of 20 patients (77%) died of disease and only 7 survived longer than 5 years.

CONCLUSIONS

The prognosis is poor since most patients with MPC of the renal pelvis and ureter initially present with advanced disease. Stage for stage the prognosis is not different from that in nonMPC urothelial cell carcinoma. Surgery is curative in less advanced cases. However, radiotherapy and systemic chemotherapy appear to be ineffective.

Bilateral Metachronous Ureteral and Renal Pelvic Carcinomas: Incidence, Clinical Presentation, Histopathology, Treatment and Outcome

PURPOSE

Metachronous bilateral UUTTs are rare. The authors reported baseline and long-term followup data for all patients diagnosed in Western Sweden during a 28-year period.

MATERIALS AND METHODS

We performed a clinical and histopathological analysis of all patients in Western Sweden surgically treated for ureteral and renal pelvic tumors from 1971 to 1998.

RESULTS

Of 768 patients a contralateral UUTT developed in 24 (3.1%) after a median of 46 months (range 2 to 232). The projected incidence after initial UUTT diagnosis was 2.7%, 5.8% and 6.5% at 5, 10 and 15 years, respectively. Median age of the 24 patients at initial UUTT diagnosis was 67 years and the median age at death was 77 years. Bladder cancer was significantly more common among patients with bilateral UUTT compared to those with unilateral UUTT (83% vs 31%, p <0.0001). Routine followup urography was normal in 9 patients 2 to 11 months before the diagnosis of the contralateral UUTT. Nine patients died of UUTT and 5 patients died of bladder cancer.

CONCLUSIONS

Bilateral subsequent upper tract tumors are rare, in general diagnosed at an older age and associated with short survival. Many patients die of bladder cancer and it may be possible to improve survival if the bladder cancer is treated early and aggressively. Routine followup urography is not indicated among patients with a tumor-free bladder and a history of UUTT.

Chronic pancreatic inflammation induced by environmental tobacco smoke inhalation in rats

OBJECTIVE

Despite a strong epidemiological association between cigarette smoking and pancreatic diseases, such as pancreatic cancer and chronic pancreatitis, the effects of long-term cigarette smoke inhalation on the pancreas have not been clearly determined. In the present study, we investigated the effect of cigarette smoke inhalation on the pancreas.

METHODS

Thirty-six female Sprague Dawley rats were exposed to two different doses of environmental tobacco smoke averaging 100 mg or 160 mg/m3 total suspended particulate matter (TSP) per m3 for 70 min twice a day for 12 wk. The animals were sacrificed and examined for the effects of tobacco smoke exposure on pancreatic morphology and function.

RESULTS

In 58% (7/12) of the animals, exposure to 160 mg/m3 TSP cigarette smoke induced a chronic pancreatic inflammatory process with fibrosis and scarring of pancreatic acinar structures. Animals with fibrotic alterations showed an induction of pancreatic pro-collagen 1 gene expression, and the infiltration of immune cells was accompanied by the expression of the inflammatory mediators MIP-1alpha, IL-1beta, and TGF-beta in 33% (4/12) of the animals. Acinar cell stress was manifested by a significant up-regulation of pancreatitis-associated protein expression (PAP) in smoke-exposed animals (smoke-exposed 6,932 +/- 1,236 vs control 3,608 +/- 305, p < 0.05). Possibly contributing to the morphological damage to the exocrine pancreas, the inhalation of cigarette smoke induced trypsinogen and chymotrypsinogen gene expression and, furthermore, reduced pancreatic enzyme content.

CONCLUSIONS

This study provides experimental evidence of morphological pancreatic damage induced by the inhalation of cigarette smoke, which is likely to be mediated by alterations of acinar cell function.

Expression of p66(Shc) protein correlates with proliferation of human prostate cancer cells

p66(Shc), an isoform of Shc adaptor proteins, is shown to mediate various signals, including cellular stress. However, little is known about its involvement in carcinogenesis. We previously showed that p66(Shc) protein level is upregulated by steroid hormones in human carcinoma cells and is higher in prostate cancer (PCa) specimens than adjacent noncancerous cells. In this study, we investigated the role of p66(Shc) protein in PCa cell proliferation. Among different PCa cell lines tested, p66(Shc) protein level showed positive correlation with cell proliferation, that is, rapid-growing cells expressed higher p66(Shc) protein than slow-growing cells. Exposure of slow-growing LNCaP C-33 cells to epidermal growth factor (EGF) and 5alpha-dihydrotestosterone (DHT) led to upregulation of proliferation and p66(Shc) protein level. Conversely, growth suppression of fast-growing cells by cellular form of prostatic acid phosphatase (cPAcP) expression, a negative growth regulator, down-regulated their p66(Shc) protein level. Additionally, increased expression of p66(Shc) protein by cDNA transfection in LNCaP C-33 cells resulted in increased cell proliferation. Cell cycle analyses showed higher percentage of p66(Shc)-overexpressing cells at S phase (24%) than control cells (17%), correlating with their growth rates. On the other hand, transient knock-down of p66(Shc) expression by RNAi in rapidly growing cells decreased their proliferation as evidenced by the reduced cell growth as well as S phase in p66(Shc)-knocked down cells. The p66(Shc) signaling in cell growth regulation is apparently mediated by extracellular signal-regulated kinase/mitogen-activated protein kinase (ERK/MAPK). Thus, our results indicate a novel role for p66(Shc) in prostate carcinogenesis, in part, promoting cell proliferation.

Urothelial carcinoma of the upper urinary tract: Comparison between the WHO/ISUP 1998 consensus classification and WHO 1999 classification system

OBJECTIVES

To compare the usefulness of World Health Organization (WHO)/International Society of Urological Pathologists 1998 consensus classification with the WHO 1999 classification in a large series of urothelial tumors of the upper urinary tract. Only a few bladder tumor studies have compared these systems.

METHODS

A clinical and histopathologic review was performed of all patients diagnosed in western Sweden between 1971 and 1998 with renal pelvic or ureteral carcinoma. We selected 555 surgically treated patients who all had a urothelial tumor on review of the pathologic findings and no bladder tumor before diagnosis of the upper tract tumor. The median follow-up was 52 months. Disease-specific survival was calculated using Kaplan-Meier estimates.

RESULTS

A total of 349 patients had Stage pTa, pT1, or pT2 tumor, with a 5-year disease-specific survival rate of 95%, 80%, and 79%, respectively. No significant difference was found in the prognosis among papillary urothelial neoplasm of low malignant potential and low-grade and high-grade tumors of the same stage. Nor was a difference found among papillary urothelial neoplasm of low malignant potential and grade 1, 2, and 3 tumors. Of the 349 patients, 171, all with high-grade Stage pT3 tumors, had a 35% disease-specific survival rate. Of these tumors, 38 were grade 2 and 133 were grade 3, with a survival rate of 49% and 25%, respectively (P <0.0037). All 35 pT4 tumors were high grade, and no patient survived past 30 months.

CONCLUSIONS

Tumor stage was a very strong predictor of prognosis in this series of patients treated with open surgery. The tumor grade had little additional prognostic value, although a small advantage was found for the WHO 1999 classification, but only for high-grade, Stage pT3 tumors.

Tumours of the ureter and renal pelvis treated with resection and renal autotransplantation: a study with up to 20 years of follow-up

OBJECTIVE

To report long-term follow-up data from patients treated with resection of urothelial neoplasms of the upper urinary tract combined with autotransplantation of the kidney.

PATIENTS AND METHODS

In a clinical and histopathological review of 23 patients who had 25 autotransplantations, they were followed for 7-20 years or until death. Nine patients had either a solitary kidney or bilateral renal pelvic tumours (group A) and 14 had a normal contralateral kidney (group B).

RESULTS

Seven operations were unsuccessful, ending in nephrectomy. Of the nine patients in group A two with high-grade renal pelvic tumours survived with no dialysis and recurrences for 127 and 238 months, respectively. Three patients required haemodialysis 0-3 times weekly for 27, 85 and 108 months, respectively. Three patients with low-grade disease developed invasive recurrences in the autotransplanted kidney after 16, 27 and 90 months, respectively, and later died from the disease. One patient died in an accident after 14 months. Of the 14 patients in group B, one developed a deeply invasive recurrence in the autotransplanted kidney after 86 months, despite frequent controls.

CONCLUSIONS

In patients with a normal contralateral kidney resection and renal autotransplantation is not indicated and might even be harmful, compared to standard nephroureterectomy. The operation might be beneficial in patients with solitary kidneys but other treatments should first be considered, including open or endoscopic resection, and nephroureterectomy and haemodialysis.

C-erb-B2 (HER2/neu) expression in synovial sarcoma of the head and neck

BACKGROUND

Synovial sarcoma is a malignant mesenchymal tumor composed of varying proportions of spindle and epithelial cell components. Because of the histologic and immunohistochemical similarity of synovial sarcoma to epithelial carcinomas, we hypothesized that the human epithelial growth factor receptor 2 (C-erb-B2, also termed HER2/neu) may contribute to the tumor phenotype and provide a new therapeutic target for this soft tissue tumor.

METHODS

Three head and neck, one chest wall, and seven extremity synovial sarcomas were evaluated for C-erb-B2 (HER2/neu) expression by immunohistochemistry, Western immunoblotting, and fluorescence in situ hybridization (FISH).

RESULTS

The head and neck cases demonstrated immunohistochemically strong positive staining, whereas tumors from other anatomic locations showed neither positive nor cytoplasmic restricted staining. Antigen-targeted antibody therapy (trastuzumab) was initiated in two patients.

CONCLUSIONS

These results demonstrate that C-erb-B2 (HER2/neu) may play a role in the tumorigenesis of synovial sarcoma; and, therefore, antigrowth factor therapies may provide a previously unrecognized pharmaceutical approach to soft tissue tumors. The data also suggest that although synovial sarcoma of the head and neck and synovial sarcoma of the extremities have similar morphologic features, they may be clinically and mechanistically distinct entities.

Synchronous bilateral ureteral and renal pelvic carcinomas

BACKGROUND

Synchronous bilateral urothelial tumors of the upper urinary tract are very rare. The authors reported baseline and long-term follow-up data for all patients in western Sweden during a 28-year period.

METHODS

The authors performed a clinical and histopathologic study of all patients in western Sweden who were diagnosed with a malignant neoplasm in the renal pelvis or ureter between 1971 and 1998.

RESULTS

Of 936 patients, 15 (1.6%) had synchronous bilateral tumors. The incidence of such tumors decreased in each successive decade. Abuse of phenacetin-containing analgesics by patients also decreased during the study period, as did the incidence of renal papillary necrosis. The median age at diagnosis of bilateral tumors was 68 years, and 80% of the patients were male. Eleven patients had bilateral tumors of the renal pelvis, two had bilateral ureteral tumors, and two had tumors of the renal pelvis and contralateral ureter. Partial renal pelvic, ureteral, or kidney resection on at least one side was possible in eight patients, and four patients were left untreated on at least one side. Only three patients underwent bilateral nephroureterectomy. Twelve patients (80%) had bladder carcinoma diagnosed either before or after diagnosis of the upper tract tumors. The median survival period for the 11 patients who received surgery for their bilateral tumors was 84 months.

CONCLUSIONS

The decreasing incidence of synchronous bilateral upper tract tumors may be related to the prohibition of phenacetin-containing analgesics in the 1960s. Partial resection with preservation of the renal parenchyma was possible in the majority of patients. Survival for patients with bilateral tumors did not differ from that of patients with unilateral tumors.

p66Shc protein is upregulated by steroid hormones in hormone-sensitive cancer cells and in primary prostate carcinomas

Members of Shc family conventionally serve as critical adaptors in tyrosine phosphorylation signal transduction pathways. p66(Shc) protein, a member of Shc family, is predominantly expressed in epithelial cells, whereas the regulation of its expression remains an enigma. We describe the effect of steroid hormones on the protein level of p66(Shc) and growth stimulation in hormone-sensitive human prostate, testicular and breast cancer cells. In DHT-treated androgen-sensitive prostate cancer LNCaP C-33 cells, the protein level of p66(Shc) was elevated by approximately 3-fold, correlating with increased cell growth. This DHT effect on p66(Shc) protein level and growth regulation was also observed in another androgen-sensitive prostate cancer cell line MDA PCa2b as well as 2 testicular cancer cell lines, Tera-1 and Tera-2 cells. Similarly, the female sex hormone estrogen had a stimulating effect on p66(Shc) protein level and proliferation in estrogen-sensitive MCF-7 breast cancer cells. The upregulation of p66(Shc) protein level by DHT was competitively abolished by Casodex, an androgen antagonist used to treat prostate cancer. Moreover, immunohistochemical analyses showed that the p66(Shc) protein level was significantly higher in primary prostate tumors than in adjacent non-cancerous cells (p < 0.05). The data collectively indicate that p66(Shc) protein levels correlate with steroid hormone-stimulated cell growth and prostate carcinogenesis.

Expression of CXCR1 and CXCR2 receptors in malignant melanoma with different metastatic potential and their role in interleukin-8 (CXCL-8)-mediated modulation of metastatic phenotype

In the present study, we examined the autocrine/paracrine role of IL-8 in melanoma growth and metastasis by analyzing the expression and functional significance of IL-8 receptors, CXCR1 and CXCR2 in human malignant melanoma cells with different metastatic potential. CXCR1 and CXCR2 mRNA and protein levels were analyzed by reverse trannscriptase-based polymerase chain reaction, immunohistochemistry, immunoprecipitation, flow cytometry and ligand binding assay in melanoma cells in vitro and xenografted in nude mice. Melanoma cells constitutively expressed CXCR1 and CXCR2 mRNA and protein. Highly metastatic A375SM cells expressed higher levels of CXCR1 and CXCR2 mRNA and protein in vitro and in vivo as compared to low metastatic A375P and non-metastatic SBC-2 melanoma cells. Treatment of SBC-2 and A375P cells with exogenously added recombinant IL-8 significantly enhanced their proliferation and invasive potential. Further neutralizing antibodies to CXCR1 and CXCR2 inhibited proliferation and invasive potential of unstimulated and IL-8-stimulated A375P cells. In summary, the data suggest that constitutive expression of CXCR1 and CXCR2 play an important role regulating the IL-8-mediated metastatic phenotype in human malignant melanoma cells.

Expression of biomarkers modulating prostate cancer angiogenesis: differential expression of annexin II in prostate carcinomas from India and USA

BACKGROUND

Prostate cancer (PCa) incidences vary with genetic, geographical and ethnic dietary background of patients while angiogenesis is modulated through exquisite interplay of tumor-stromal interactions of biological macromolecules. We hypothesized that comprehensive analysis of four biomarkers modulating angiogenesis in PCa progression in two diverse populations might explain the variance in the incidence rates.

RESULTS

Immunohistochemical analysis of 42 PCa biopsies reveals that though Anx-II expression is lost in both the Indian and American population with Gleason scores (GS) ranging between 6 and 10, up to 25 % of cells in the entire high grade (GS > 8) PD PCa samples from US show intense focal membrane staining for Anx-II unlike similarly graded specimens from India. Consistent with this observation, the prostate cancer cell lines PC-3, DU-145 and MDA PCa 2A, but not LNCaP-R, LNCAP-UR or MDA PCa 2B cell lines, express Anx-II. Transcriptional reactivation of Anx-II gene with Aza-dC could not entirely account for loss of Anx-II protein in primary PCa. Cyclooxygenase-2 (COX-2) was moderately expressed in most of high grade PIN and some MD PCa and surrounding stroma. COX-2 was not expressed in PD PCa (GS approximately 7-10), while adjacent smooth muscles cells stained weakly positive. Decorin expression was observed only in high grade PIN but not in any of the prostate cancers, atrophy or BPH while stromal areas of BPH stained intensively for DCN and decreased with advancing stages of PCa. Versican expression was weak in most of the MD PCa, moderate in all of BPH, moderately focal in PD PC, weak and focal in PIN, atrophy and adjacent stroma.

CONCLUSIONS

Expression of pro- and anti-angiogenic modulators changes with stage of PCa but correlates with angiogenic status. Focal membrane staining of Anx-II reappears in high grade PCa specimens only from US indicating differential expression of Anx-II. COX-2 stained stronger in American specimens compared to Indian specimens. The sequential expression of DCN and VCN in progressive stages was similar in specimens from India and USA indicating no population-based differences. The mechanistic and regulatory role of Anx-II in PCa progression warrants further investigation.

Dysregulated expression of MIC-1/PDF in human prostate tumor cells

As a part of the study to identify genes associated with hormone-refractory stage of human prostate cancer, we have recently identified several genetic and epigenetic changes that seem to be associated with the progression of androgen-sensitive to androgen-independent prostate tumor cells. In the present study, we report a novel gene, macrophage inhibitory cytokine-1 (MIC-1) also known as prostate derived factor (PDF), that was highly expressed in androgen-independent LNCaP-C81 cells and its metastatic variant LNCaP-Ln3 compared to androgen-sensitive LNCaP-C33 cells. The MIC-1/PDF expression was dysregulated (very low to non-detectable) in the androgen-independent PC3 and DU145 cells. Interestingly, serum factors demonstrated a differential regulation of MIC-1/PDF in the androgen-sensitive and the androgen-independent cells of LNCaP cells. Immunohistochemical analysis on 15 prostatic adenocarcinomas showed a weak staining in the benign prostatic glandular area (intensity score 2.38+/-0.25; n=13), while the immunoreactivity was significantly stronger (p<0.05) in areas of adenocarcinoma (score 7.33+/-0.88; n=15). Altogether, these data suggest that the serum factors (including androgens and cytokines) might contribute to the regulation of the MIC-1/PDF gene that seems to be associated with the progression of prostate cancer.