Features Of Neoplasia Research Articles

The feasibility and outcomes of metabolic and bariatric surgery prior to neoplastic therapy

BackgroundMetabolic and bariatric surgery (MBS) is a potent intervention for addressing obesity-related medical conditions and achieving sustainable weight loss. Beyond its conventional role, MBS has demonstrated potential to serve as a transitional step for patients requiring various interventions. However, the implications of MBS in the context of neoplasia remain understudied. ObjectivesTo explore the feasibility of MBS as a possible attempt to reduce surgical and treatment risks in patients with benign tumors or low-grade cancers. SettingMulticenter review from twelve tertiary referral centers spanning 8 countries. MethodsA retrospective review of patients with a diagnosis of primary neoplasia, deemed inoperable or high-risk due to obesity, and receiving primary MBS prior to neoplastic therapy. Data encompassed baseline characteristics, neoplasia characteristics, MBS outcomes, and neoplastic therapy outcomes. ResultsThirty-seven patients (median age 52 years, 75.7% female, median BMI of 49.1 kg/m2) were included. There were 9 distinct organs of origin of primary neoplasia, with the endometrium (43.2%) being the most common, followed by the pancreas, colon, kidney and breast. Sleeve gastrectomy (SG) was the most commonly performed MBS procedure (78.4%), with no MBS-related complications or mortalities reported over an average of 4.3 ± 3.9 years. Thirty-one patients (83.8%) eventually underwent neoplastic surgery, with a mean BMI decrease from 49.9 kg/m2 to 39.7 kg/m2 at surgery over an average of 5.8 ± 4.8 months. There were 2 (6.7%) documented mortalities associated with neoplastic surgical intervention. ConclusionsThis study highlights the potential feasibility of employing MBS prior to neoplastic therapy in patients with low-grade, less aggressive neoplasms in the context of obesity. This underscores the importance of providing a personalized, case-to-case multidisciplinary approach in the management of these patients.

Modulation of miR-192/NF-κB/ TGF-β/ E-cadherin by thymoquinone protects against diethylnitrosamine /carbon tetrachloride hepatotoxicity.

Scientific efforts have been made for a better understanding of the pathogenesis of hepatocellular carcinoma (HCC). We investigated the possible role of miR-192/nuclear factor-κB (NF-κB)/transforming growth factor-β (TGF-β)/E-cadherin in hepatic tumorigenesis. We expected a modulatory impact of thymoquinone. Thirty adult male rats were assigned into 3 groups (n = 10); (1) Control group. Group (2): Experimental HCC induced by intraperitoneal injection of diethylnitrosamine (DENA) followed by carbon tetrachloride (CCl4). Group (3): Thymoquinone 20 mg kg-1/oral supplementation starting from the model induction to the end of the 8th week. The HCC (DENA-CCL4) model was confirmed by elevated serum levels of alpha-fetoprotein and transaminases (ALT, AST) and by histopathological examination which denoted marked cellular atypia and features of neoplasia. Suppressed hepatic miR-192 and E-cadherin expression were detected in the HCC (DENA-CCL4) group accompanied by elevated tumor necrosis factor (TNF-α), interleukin (IL6)/NF-κB & TGF-β1. Thymoquinone treatment protected the rat livers from hepatic tumorigenesis. Thymoquinone diminished (P < 0.001) alpha-fetoprotein and improved ALT, AST. It preserved hepatic miR-192 and normal E-cadherin expression. Thymoquinone-treated rats showed abrogated TNF-α, IL6/NF-κB/TGF-β. Thymoquinone increased cell apoptosis markers Bax/Bcl2 and diminished cellular atypia. Pearson's correlations revealed positive association between miR-192 expression and E-cadherin and Bax/Bcl2 as well, and it was negatively correlated to alpha-fetoprotein, NF-κB and TGF-β and the cellular atypia score. In conclusion, thymoquinone protected the liver tissues through preserving miR-192 and E-cadherin and aborting NF-κB & TGF-β signaling. The current results highlight a new role for thymoquinone in preventing hepatic tumorigenesis.

Detection of Epstein-Barr virus in gastric adenocarcinoma: qPCR and FISH comparison

EBV-associated gastric cancer accounts for about 10% of all gastric carcinomas worldwide. We aimed to verify the prevalence of EBV in gastric adenocarcinoma samples using FISH and qPCR and comparing the results obtained by both techniques. Gastric cancer samples from 191 cases were analyzed. The FISH assay was performed to detect small EBV RNAs (EBER1) and qPCR was performed to detect the EBV-EBNA-1 gene region. Cohen’s kappa index and the chi-square test were used to compare the methodologies and investigate correlations with the clinical-pathological data of the gastric adenocarcinoma patients. Most of the patients were men, and the average age was 60 years. The intestinal subtype cancer presented more aggressive stages with 90% of patients having a reactive FISH for EBV (EBV+), although the virus infection frequency in epithelial gastric tissue was only 1%. No positive association with clinicopathological features and EBV+ was found by FISH. Using qPCR analysis, the percentage of positive samples was lower (52.4%), and a positive association was found in samples from older patients (> 60 years). Interestingly, 71 qPCR-negative cases were detected by FISH in the presence of non-epithelial cells and in 10 qPCR-positive cases with no evidence of EBV according to FISH. The concordance between the two techniques was low, with only 57.6%. FISH is more informative for associating the gastric carcinoma with EBV positivity in tumor/epithelial cells; however, qPCR can provide relevant information regarding the progression and characteristics of neoplasia.

Histopathology Feature Mining and Association with Hyperspectral Imaging for the Detection of Squamous Neoplasia

Hyperspectral imaging (HSI) is a noninvasive optical modality that holds promise for early detection of tongue lesions. Spectral signatures generated by HSI contain important diagnostic information that can be used to predict the disease status of the examined biological tissue. However, the underlying pathophysiology for the spectral difference between normal and neoplastic tissue is not well understood. Here, we propose to leverage digital pathology and predictive modeling to select the most discriminative features from digitized histological images to differentiate tongue neoplasia from normal tissue, and then correlate these discriminative pathological features with corresponding spectral signatures of the neoplasia. We demonstrated the association between the histological features quantifying the architectural features of neoplasia on a microscopic scale, with the spectral signature of the corresponding tissue measured by HSI on a macroscopic level. This study may provide insight into the pathophysiology underlying the hyperspectral dataset.

SIRT1 promotes GLUT1 expression and bladder cancer progression via regulation of glucose uptake.

Bladder cancer (BC) is one of the most common tumors. Metabolic reprogramming is a feature of neoplasia and tumor growth. Understanding the metabolic alterations in bladder cancer may provide new directions for bladder cancer treatment. Sirtuin 1 (SIRT1) is a lysine deacetylase of multiple targets including metabolic regulators. In pancreatic cancer, the loss of SIRT1 is accompanied by a decreased expression of proteins in the glycolysis pathway, such as GLUT1, and cancer cell proliferation. Thus, we hypothesize that SIRT1 may interact with GLUT1 to modulate the proliferation and glycolysis phenotype in bladder cancer. In the present study, the expression of SIRT1 and GLUT1 was upregulated in BC tissues and cell lines and positively correlated in tissue samples. SIRT1 overexpression or GLUT1 overexpression alone was sufficient to promote cell proliferation and glucose uptake in BC cells. EX527, a specific inhibitor of SIRT1, exerted an opposing effect on bladder cancer proliferation and glucose uptake. The effect of EX527 could be partially reversed by GLUT1 overexpression. More importantly, SIRT1 overexpression significantly promoted the transcriptional activity and expression of GLUT1, indicating that SIRT1 increases the transcription activity and expression of GLUT1, therefore, promoting the cell proliferation and glycolysis in BC cells. Our study first reported that SIRT1/GLUT1 axis promotes bladder cancer progression via regulation of glucose uptake.

Sirtuin 1 stimulates the proliferation and the expression of glycolysis genes in pancreatic neoplastic lesions.

Metabolic reprogramming is a feature of neoplasia and tumor growth. Sirtuin 1 (SIRT1) is a lysine deacetylase of multiple targets including metabolic regulators such as p53. SIRT1 regulates metaplasia in the pancreas. Nevertheless, it is unclear if SIRT1 affects the development of neoplastic lesions and whether metabolic gene expression is altered.To assess neoplastic lesion development, mice with a pancreas-specific loss of Sirt1 (Pdx1-Cre;Sirt1-lox) were bred into a KrasG12D mutant background (KC) that predisposes to the development of pancreatic intra-epithelial neoplasia (PanIN) and ductal adenocarcinoma (PDAC). Similar grade PanIN lesions developed in KC and KC;Sirt1-lox mice but specifically early mucinous PanINs occupied 40% less area in the KC;Sirt1-lox line, attributed to reduced proliferation. This was accompanied by reduced expression of proteins in the glycolysis pathway, such as GLUT1 and GAPDH.The stimulatory effect of SIRT1 on proliferation and glycolysis gene expression was confirmed in a human PDAC cell line. In resected PDAC samples, higher proliferation and expression of glycolysis genes correlated with poor patient survival. SIRT1 expression per se was not prognostic but low expression of Cell Cycle and Apoptosis Regulator 2 (CCAR2), a reported SIRT1 inhibitor, corresponded to poor patient survival.These findings open perspectives for novel targeted therapies in pancreatic cancer.

Polycystic kidney disease and cancer after renal transplantation.

Autosomal dominant polycystic kidney disease (ADPKD), the most common form of polycystic kidney disease (PKD), is a disorder with characteristics of neoplasia. However, it is not known whether renal transplant recipients with PKD have an increased risk of cancer. Data from the Scientific Registry of Transplant Recipients, which contains information on all solid organ transplant recipients in the United States, were linked to 15 population-based cancer registries in the United States. For PKD recipients, we compared overall cancer risk with that in the general population. We also compared cancer incidence in PKD versus non-PKD renal transplant recipients using Poisson regression, and we determined incidence rate ratios (IRRs) adjusted for age, sex, race/ethnicity, dialysis duration, and time since transplantation. The study included 10,166 kidney recipients with PKD and 107,339 without PKD. Cancer incidence in PKD recipients was 1233.6 per 100,000 person-years, 48% higher than expected in the general population (standardized incidence ratio, 1.48; 95% confidence interval [95% CI], 1.37 to 1.60), whereas cancer incidence in non-PKD recipients was 1119.1 per 100,000 person-years. The unadjusted incidence was higher in PKD than in non-PKD recipients (IRR, 1.10; 95% CI, 1.01 to 1.20). However, PKD recipients were older (median age at transplantation, 51 years versus 45 years for non-PKD recipients), and after multivariable adjustment, cancer incidence was lower in PKD recipients than in others (IRR, 0.84; 95% CI, 0.77 to 0.91). The reason for the lower cancer risk in PKD recipients is not known but may relate to biologic characteristics of ADPKD or to cancer risk behaviors associated with ADPKD.

Barrett-Ösophagus

Whereas attention in the past has been focused on goblet cells as the primary marker for Barrett's esophagus (BE), the recent change in the definition now includes the non-goblet cell columnar cell-lined esophagus. In the present study the histological features of neoplasia of the lower esophagus and esophago-gastric junction in a German cohort were examined using immunohistochemical staining for MUC, CD10, intestinal and gastric type major tight junction proteins (claudins). Experimental studies using rat duodenogastric content reflux models have also been performed and data show that most neoplastic lesions of the esophageal glands in humans express gastric mucin phenotypes. Cardiac type mucosa was the main histological type in the surrounding mucosa of neoplastic lesions; however, most cardiac type mucosa has intestinal type tight junction proteins. BE with goblet cells has been reported to originate from stem cells located in the basal layer of esophageal squamous cell epithelium in previous models. However, the cardiac type mucosa seems to develop from the site of the stomach and not from the basal layer of esophageal squamous cell epithelium according to our model.

Cancer in five Italian nursing homes

Purpose of the study: No information is presently available on cancer incidence and management in the nursing homes in Italy as well as in the other European countries. The aim of this analysis was to provide information on the characteristic of neoplasia and therapeutic approach in 5 nursing homes Methods: The charts of all neoplastic patients admitted in five nursing homes of the Don Carlo Gnocchi Foundation in the Lombardy Region (Palazzolo, Malnate, Girola, Salice, Pessano) from January 2009 to December 2011 were analyzed for tumor type, age, previous antineoplastic treatment, and associated diseases (CIRS) Results: In these Foundation's nursing homes (total 1074 beds), in the Lombardy region, we observed 136 histologically proven cancer cases. The median age was 86.9 years (range 76–101), 23 (17%) were males and 113 (83%) females. Of 136 evaluable cases 104 were frail (77.6%), 11 vulnerable (8.2%) and 19 fit (14.2%). Breast cancer was observed in 31 pts, of whom 5 with metastatic disease and 4 with locally advanced disease. Hormone therapy was administered in all, but none of these cases was treated with chemotherapy. In 24 cases, a colo-rectal cancer had been diagnosed but only 1 had metastatic disease. Prostatic cancer was observed in 19 cases, 6 of whom handled with hormone therapy. Eleven cases of lung cancer were observed, 2 of whommetatastatic. A genito-urinary cancer was observed in 16 cases: 6 with bladder cancer; 2 ureteral cancer, 2 cervical cancer, 3 endometrial, 1 vulvar, 1 ovarian and 1 kidney. Seven skin tumors were noticed: 4 were melanoma and the other squamous skin cancer.We also noticed 4 cases of lymphoma and 3 cases of chronic leukemia, but only one could receive chemotherapy while being in the nursing home. The remaining 23 cases were distributed among gastroesophageal, pancreatic and head and neck cancer. As a whole, 19 cases were in an advanced stage, but for none, with the exception of a case of malignant lymphoma, chemotherapy was considered while being in the nursing home. Concerning the medical approach to the neoplasia in these patients our impression is that chemotherapy was not considered to be feasible because of frailty, while the endocrine therapy with aromatase inhibitors was administered in all cases with locally advanced and metastatic breast cancer and used in cases with prostatic carcinoma, both for the relative easiness in prescription and administration. Conclusion: The majority of elderly pts in these nursing homes were frail, with a female predominance, cancer being quite often only one of the multiple heavy problems. In these pts, a complete diagnostic assessment may not be possible in all instances .Chemotherapy should be planned all the time in cases with chemosensitive neoplasia such as malignant lymphomas, while in the majority of the other cases should not be excluded a priori. Our preliminary experience in treating with chemotherapy in our division of Geriatric Oncology patients coming from the nursing home within the same institution and replacing them again there after chemotherapy is positive.

Cytohistologic Correlation Study of Thyroid Lesions with Emphasis on the Diagnostic Pitfalls

Fine needle aspiration of thyroid is proven to be the most economical and reliable diagnostic tool for distinguishing neoplastic from non-neoplastic nodules for better selection of patients for surgery. The aim of this study is to evaluate the diagnostic accuracy of thyroid cytology performed at our institution by correlating its results with final histopathological diagnosis. This retrospective study used two-hundred and seventy-one cases of thyroid cytology performed at King Abdulaziz University Hospital between 1995 and 2007. The corresponding histopathological slides were reviewed. The sensitivity and specificity of cytology for detecting neoplasia at our institute were calculated at 71% and 93%, respectively. The most common benign lesion diagnosed was multinodular goiter (46%), and the most common malignancy was Papillary Thyroid Carcinoma (16%). The major cause of false positive diagnosis is the overlapping cytological features in hyperplasia that can be misinterpreted as features of neoplasia; whereas the main reason of false negative diagnosis is failure to recognize the follicular variant of papillary thyroid carcinoma. The study confirmed the efficiency of cytology in the evaluation of both nodular and diffuse thyroid lesions. However; cytopathologists should be aware of the potential diagnostic pitfalls in order to achieve a higher rate of diagnostic accuracy.

Hematopoietic Proliferative Lesions in the Spleen of rasH2 Transgenic Mice Treated with MNU

In this study, rasH2-Tg mice treated with N-methyl-N-nitrosurea (MNU) developed exuberant hematoproliferative changes in the spleen that included dysplasia and features of neoplasia. Hematoproliferative change was characterized as exuberant proliferation of hematopoietic cells within the spleen that distorted but did not displace normal splenic morphologic features. The hematopoietic cells were of mixed lineage, but one type, often erythroid, predominated. Cellular atypia was present in all mice with hematoproliferative change, and dysplasia was present in five of eight examined. Hematoproliferative neoplasia was characterized by similar cytologic features but also resulted in displacement/disruption of normal splenic architecture and increased numbers of unidentified blast cells. One case was differentiated toward myeloid proliferation, suggesting granulocytic leukemia. Affected mice had other neoplasms, such as lymphoma and anemia. These proliferative and dysplastic lesions of the spleen in rasH2-Tg mice treated with MNU require additional characterization to definitively differentiate them from the reactive hematopoiesis that can occur in response to inflammatory, neoplastic, or hematopoietic insults in mice.

Cancer in Crohnʼs Disease patients treated with infliximab: A long-term multicenter matched pair study

The long-term risk of neoplasia in Crohn's disease (CD) patients treated with infliximab is undefined. The aim was to assess, in a multicenter, matched-pair study, whether infliximab use in CD is associated with an increased frequency of neoplasia in the long term. A multicenter, long-term, matched-pair study was conducted in 12 referral inflammatory bowel disease (IBD) centers. An initial cohort of 808 CD patients, including 404 infliximab-treated (CD-IFX) and 404 matched CD controls never treated with infliximab (CD-C) studied from 1999 to 2004, was followed up for an additional 4 years (2004-2008). Cases and controls were matched for: sex, age (±5 years), CD site, follow-up (±5 years), immunosuppressant use, and CD duration (±5 years). From 1999 to 2008 the frequency and characteristics of neoplasia were compared between CD-IFX and CD-C. In 2008, 591 patients (304 CD-IFX, 287 CD-C) were in follow-up. Matched couples included 442 patients: 221 CD-IFX and 221 CD-C (median follow-up, months: 72, range 48-114 versus 75, range 44-114). From 1999 to 2008 the frequency of neoplasia among the 591 patients did not differ between CD-IFX (12/304; 3.94%) and CD-C (12/287; 4.19%; P = 0.95). A comparable frequency of neoplasia was also observed between the 221 matched couples (CD-IFX: 8/221; 3.61% versus CD-C: 9/221; 4.07%; P = 1). No specific histotype of cancer appeared associated with infliximab use. The frequency of neoplasia was comparable in an adult population of CD patients treated or not with infliximab, matched for clinical variables and followed up for a median of 6 years.

Age-related methylation in normal colon mucosa differs between the proximal and distal colon in patients who underwent colonoscopy

Objectives To examine the difference in the methylation status in normal colon mucosa between the proximal and distal colon, in relation to the correlation between the methylation status of normal mucosa and characteristics of neoplasia. Design and methods Paired biopsy specimens of normal mucosa from the proximal and distal colon of 82 patients who underwent colonoscopy were obtained. The methylation status of the promoter region of estrogen receptor 1 ( ESR1) and myogenic differentiation 1 ( MYOD1) was examined. Results Normal mucosa was more highly methylated in the distal than in the proximal colon in both ESR1 and MYOD1 loci ( p < 0.0001 and p = 0.0009, respectively). Advanced characteristics of polyps in the distal colon were frequently observed in patients with lower methylation of ESR1 in the distal colon normal mucosa. Conclusions Methylation levels in normal mucosa differ between the proximal and distal colon, and lower methylation of ESR1 in the distal colon normal mucosa may correlate with advanced features of neoplasia in the distal colon.

Genetic and epigenetic alterations of Ras signalling pathway in colorectal neoplasia: analysis based on tumour clinicopathological features

Activation of RAS signalling induced by K-ras/BRAF mutations is a hallmark of colorectal tumours. In addition, Ras association domain families 1 and 2 (RASSF1 and RASSF2), the negative regulators of K-ras, are often inactivated by methylation of the promoter region in those tumours. However, reports showing differences in the occurrence of these alterations on the basis of tumour characteristics have been scarce. We analysed K-ras/BRAF mutations and the methylation status of RASSF1 and RASSF2 promoter regions in 120 colorectal adenomas with respect to their clinicopathological features. K-ras/BRAF mutations and RASSF2 methylation were observed in 49 (41%) and 30 (25%) of the samples, respectively, while RASSF1 methylation was observed in only 3 (2.5%). Adenomas with RASSF2 methylation often carried K-ras/BRAF mutations simultaneously (22 out of 30, P<0.01). Multivariate analysis revealed that the concomitance of these alterations was frequently observed in serrated adenomas (odds ratio (OR) 11.11; 95% confidence interval (CI) 1.96–63.00), but rarely in adenomas located in the sigmoid or descending colon (OR 0.13; 95% CI 0.03–0.58). A comparison between adenomas and cancers showed a significantly higher prevalence of these alterations in cancers than in adenomas in the proximal colon (58 vs 27%, P=0.02). Frequency and the time point of the occurrence of Ras signalling disorders differ according to colorectal neoplasia’s characteristics, particularly the location.

Reversal of p53 epigenetic silencing in multiple myeloma permits apoptosis by a p53 activator

Inactivation of the p53 pathway is a common feature of neoplasia. Dysregulation of the p53 pathway has been shown to involve mutations of p53, increased expression of the p53 inhibitor HDM-2, or epigenetic silencing of the p53 promoter. In multiple myeloma, a neoplasia of terminally differentiated B cells, p53 mutations and deletions are relatively rare and occur in late stage disease. Here, we show that the p53 promoter is hypermethylated in several multiple myeloma cell lines in comparison to normal plasma cells. Two cell lines containing mutant p53, Lp-1 and OPM-2, show a methylation pattern that suggests that they contain one methylated and one unmethylated mutant allele. Two other cell lines, KMS-11 and OPM-2, show hypermethylation of p53 with a lack of expression. In all cell lines tested, treatment with a demethylating agents results in higher expression of p53. Furthermore, following increased expression of p53, treatment of the myeloma cell lines with a p53 activating peptide induces apoptosis. Therefore, combinatorial treatment with a demethylating agent followed by delivery of a p53 activating peptide may be an effective therapeutic strategy against multiple myeloma.

Idiopathic sclerosing orbital pseudotumor in seven cats

Objective To review the clinical presentation and histopathologic findings on a series of cats with orbital fibrotic disease and compare the data to that of humans with sclerosing orbital pseudotumor. Animals A retrospective study was undertaken, which identified tissue samples from seven cats between 1997 and 2002 with a history of orbital mass effect and pathology characterized by fibrous tissue proliferation. Procedure Information was obtained from medical records for affected cats, including age, sex, clinical signs, management, and outcome, with histopathology re‐examined. Results Six of seven cats presented with unilateral orbital involvement that progressed to bilateral orbital disease despite treatment. Onset was insidious, evolving over weeks to months and was associated with fixation of orbital structures. Owners of six of the cats opted for euthanasia because of disease progression and pain. Histopathology of affected orbital tissue included extensive fibrosis with encapsulation of normal tissues without characteristics of neoplasia. Conclusions Clinical findings and histopathology of globes and orbital tissues in cats bore many similarities to idiopathic sclerosing orbital pseudotumor in humans. In cats, the prognosis for the globe appears to be poor but an elucidation of the pathogenesis and earlier diagnosis coupled with more aggressive treatment modalities as indicated in humans may be beneficial.

Prognostic value of cell cycle regulators p27 and cyclin E: Tissue microarray analysis of 1753 women enrolled in SWOG breast cancer trial 9313

507 Background: Abnormal cell proliferation is a common feature of neoplasia and associations between poor clinical outcome and abnormal expression of cell cycle regulatory proteins have been shown in population-based and clinical studies. Methods: Using tissue microarray, we evaluated the prognostic value of cell cycle regulators p27 and cyclin E by IHC in 1,753 of 3,122 (56%) women enrolled in SWOG Intergroup Trial 9313. The protocol compared DFS and OS in women with primary breast cancer who received doxorubicin and cyclophosphamide administered either concurrently (n=1595) or sequentially (n=1527). The two arms of the study showed equivalence of treatment regimens, p=0.26 (Haskell CM; Proc ASCO 21:36a (#142), 2002). Median age was 47 (range 21–76); data collected included race, stage, and menopausal nodal, and ER/PR status. Expression of p27 and cyclin E was rated from 1–7 and dichotomized at the median score for Cox regression analysis. Median follow-up is 7 years. Results: p27 was below median expre...

Molecular genetic evaluation of fluorescence diagnosis in bladder cancer

Fluorescence diagnosis of superficial bladder cancer using 5-aminolevulinic acid (ALA) is a highly sensitive technique (95%). However, the specificity is only 60-70% due to false-positive results after histopathological examination. We hypothesized that the biopsies in fluorescence endoscopy could represent early preneoplastic lesions not detectable by histopathology. In order to evaluate the specificity of fluorescence endoscopy at the molecular genetic level we performed comparative genomic hybridization (CGH) and investigated telomerase activity of ALA-positive tissue samples. For CGH, DNA was isolated from 5-10 frozen sections. Tumor and normal (control) DNAs were amplified by DOP-PCR and labeled with biotin-dUTP and digoxigenin-dUTP, respectively. Hybridization and detection were carried out according to standard protocols. Telomerase activity was analyzed using a non-radioactive system (TRAP-assay). In 33 out of 118 bladder cancer cases (28%) detected by conventional cystoscopy, additional suspicious areas were found using ALA. CGH revealed genetic changes in 27% of samples with non-malignant histological diagnoses. Telomerase activity was found in 59% of these samples. Tumor samples showed genetic alterations in 84% and in 69% telomerase activity occurred. The type of genetic alterations in the normal biopsies was identical to the tumors. Based on these molecular data, the portion of false-positive results obtained by fluorescence diagnosis is lower than defined by histopathology alone. Genetic alterations and activation of telomerase activity are early events of tumor development in bladder cancer occurring earlier than histological features of neoplasia. The clinical importance of fluorescence diagnosis and the possible reduction of the recurrence rate have to be shown in ongoing clinical studies.

Importance of and approaches to quantification of hepatocyte apoptosis.

Abnormal regulation of the life cycle of cells is a key feature of neoplasia. The net increase and growth of initiated cells, preneoplastic lesions, and tumors is highly dependent on rates of both cell proliferation and cell death. Studies of mechanisms involved in regulation of cell death and the development of methods to detect dying and dead cells thus appear to be as important as measurements of cell proliferation in understanding the growth of both normal, preneoplastic and neoplastic lesions. This article describes apoptosis in the mouse liver and its potential role in liver carcinogenesis. Quantitation of hepatocyte apoptosis is a emerging and evolving research area that will require evaluations as thoroughly as those performed with cell proliferation in order to understand all the variables that might influence its occurrence, measurement, and interpretations. Utilizing available data, various methodologies for identifying hepatocyte apoptosis are presented and compared. Aspects important for the quantitation of apoptosis in liver are emphasized. Accurate quantitation of apoptosis, in conjunction with proliferation measurements, is critical for investigations of the mechanisms of chemically induced carcinogenesis and the development of assays for growth alterations and can be applied to biologically based cancer models.

Biodistribution of photosensitizing agents

1. 1. The features of neoplasia which predict for drug responsiveness are rapid growth and/or inefficient repair of damage, especially to DNA. 2. 2. PDT has the advantage of yielding responses regardless of the growth fraction of a tumor, and repair appears to play only a minor role. 3. 3. While an entirely different spectrum of tumors can be targeted with PDT, the perhaps unavoidable accompaniment is that a new set of rules for efficacy will need to be established. 4. 4. The selectivity of PDT is based on the need for irradiation which can be directed, along with the short tissue half-life of the cytotoxic product, singlet oxygen. Sensitizers which target specific cellular organelles could promote PDT efficacy, if in vitro data (Woodbum et at., 1992b Photochem. Photobiol. 55, 697–704) can be translated into clinical practice. 5. 5. It remains to be established whether total drug distribution to neoplastic tissues or concentration in specific sub-cellular sites is the more important factor. 6. 6. Questions relating to the role of biodistribution as a factor in efficacy of PDT sensitizers of photosensitizers remain to be explored. Just as the political cartographers are grappling with changes in territorial boundaries of known lands, we continue to clarify the rules relating to PDT boundaries. In this regard, it is clearly important for determinants of pharmacokinetics and biodistribution to be evaluated and understood. 7. 7. Once clinical reports on the “second generation” agents are published, we may get a better picture, although it is not unusual for clinical reports to raise more questions than they answer. 8. 8. It seems safe to conclude that there is nothing “magic” about HPD, and that additional efficacious photosensitizers for PDT can be produced. 9. 9. If we find that a wide variety of different structures are useful in the clinic, a likely conclusion is that there are multiple mechanisms of tumor localization. Since the nature of neoplasia is so diverse, this possibility should not be surprising. 10. 10. In view of the finding, cited above, that liposomes show about the same degree of tumor selectivity as does Photofrin, it may be feasible to target any efficient photosensitizer for neoplastic tissues by development of an appropriate delivery system.