Survival and Inflammatory Response in Adipose-derived Mesenchymal Stem Cell-enriched Mouse Fat Grafts.

BACKGROUND: Adipose tissue-derived mesenchymal stem cells (ATMSCs) are currently used in grafting procedures in a number of clinical trials. The reconstructive role of such cells in fat graft enrichment is largely unclear. This study was undertaken to assess survival and inflammatory response in fat grafts enriched with ATMSCs in mice. METHODS: ATMSC-enriched adipose tissue was grafted subcutaneously in a clinically relevant manner in mice, and survival and inflammatory response were determined by bioluminescence imaging of transgenic tissue constitutively expressing luciferase or driven by inflammation in wild-type animals. RESULTS: Only a minor fraction of ATMSCs transplanted subcutaneously were found to survive long term, yet fat grafts enriched with ATMSCs showed improved survival for a limited period, compared with no enrichment. NF-κB activity was transiently increased in ATMSC-enriched grafts, and the grafts responded adequately to a proinflammatory stimulus. In one animal, cells originating from the subcutaneous graft were found at a site of inflammation distant from the site of engraftment. CONCLUSION: ATMSCs display limited subcutaneous survival. Still, ATMSC enrichment may improve the outcome of adipose tissue grafting procedures by facilitating short-term graft survival and adequate inflammatory responses. Migration of cells from grafted adipose tissue requires further investigation.

Stem cell marker-positive stellate cells and mast cells are reduced in benign-appearing bladder tissue in patients with urothelial carcinoma.

Survival after invasive bladder cancer has improved less than that of other common non-skin cancers. In many types of malignancy, treatment failure has been attributed to therapy-resistant stem-like cancer cells. Our aim was therefore to determine identities of stem cell marker-positive cells in bladder cancer tissue and to investigate possible associations between these cells and different forms of bladder neoplasia. We investigated tissue from 52 patients with bladder neoplasia and 18 patients with benign bladder conditions, from a cohort that had been previously described with regard to diagnosis and outcome. The samples were analysed immunohistologically for the stem cell markers aldehyde dehydrogenase 1 A1 (ALDH1) and CD44, and markers of cell differentiation. The majority of stem cell marker-positive cells were located in connective tissue, and a smaller fraction in epithelial tissue. Stem cell marker-positive cells exhibiting possible stem cell characteristics included cells in deeper locations of benign and malignant epithelium, and sub-endothelial cells in patients with or without neoplasia. Stem cell marker-positive cells with non-stem cell character included stellate cells, mast cells, endothelial cells, foamy histiocytes, and neurons. Significantly, ALDH1+ stellate cells and ALDH1+ mast cells were reduced in number in stroma of benign-appearing mucosa of bladder cancer patients. The stem cell markers ALDH1 and CD44 label several types of differentiated cells in bladder tissue. ALDH1+ stellate cells and mast cells appear to be reduced in stroma of normal-appearing mucosa of bladder cancer patients, and may be part of a "field effect" in cancer-near areas.

Women with familial risk for breast cancer have an increased frequency of aldehyde dehydrogenase expressing cells in breast ductules.

BACKGROUND: Knowledge is limited regarding the association between stem cells in histologically benign breast tissue and risk factors for breast cancer, and hence we addressed this issue in the present study. Recently, we assessed the histology of benign breast tissue from cancer and non-cancer patients for cells positive for the putative stem cell marker aldehyde dehydrogenase 1 A1 (ALDH), and the findings indicated an association between expression of ALDH and the hormonal factors menopause and hormone therapy. The current investigation examined possible associations between various known clinical and genetic risk factors for breast cancer and cellular expression of ALDH in ductules in benign human breast tissue. METHODS: The study included breast surgery patients that were BRCA1/2 mutation carriers without breast cancer (n = 23), had BRCA1/2 (n = 28) or sporadic (n = 21) breast cancer, or required non-cancer-related mammoplasty (n = 34). The distribution and frequency of ALDH-immunolabelled cells were correlated to patient subgroups with different risk factors, using mammoplasty patients as a control group. Statistical analyses comprised linear and logistic regression, Spearman's rank test, Pearson's test, and Fisher's exact test. In two-tailed tests, p < 0.05 was considered significant. RESULTS: A strong association was found between family history of breast cancer and a high frequency of ALDH+ cells (p = 0.001) at all ductular levels in all groups, regardless of BRCA status, age, parity, or occurrence of cancer. In pre-menopausal non-BRCA cancer patients, the frequency of ALDH+ cells increased with age (p < 0.01) but decreased with increasing parity (p < 0.03). High frequencies of ALDH+ cells were found in the non-basal ductular levels in BRCA1 mutation carriers (p = 0.03), but in the basal ductular level in BRCA2 cancer patients (p = 0.02). Among post-menopausal patients, only on-going hormone replacement therapy was correlated with a high number of ALDH+ cells (p < 0.03). CONCLUSION: In histologically normal breast tissue, we found a positive association between the frequency of ductular ALDH+ cells and several breast cancer risk factors, particularly family history of this disease, which supports previous evidence that ALDH plays a role in breast cancer.

Distribution of aldehyde dehydrogenase 1-positive stem cells in benign mammary tissue from women with and without breast cancer.

AIMS: Aldehyde dehydrogenase 1 (ALDH1) in female breast tissue has been linked to stem cells, but little is known about the benign cellular organization in situ. We investigated the distribution of ALDH1-immunoreactive (ALDH1+) cells in histomorphologically benign breast tissue from 28 women with or without breast cancer. METHODS AND RESULTS: ALDH1+ cells were detected in benign tissue of women aged 20-72 years, located most commonly at the luminal and intermediate ductular levels and in the stroma. ALDH1+ cell populations and Ki67+ cell populations were present in separate ductules, both cell types rarely showing epithelial differentiation. ALDH1+ cells were non-reactive to Ki67 and oestrogen receptor. Stromal round/oval ALDH1+ non-leukocyte cells in both age groups expressed contractile protein. There was a lower concentration of luminal and intermediate ductular ALDH1+ cells in postmenopausal women than in premenopausal women, and in cancer patients than in non-cancer patients, and a higher concentration in women receiving exogenous hormones. CONCLUSIONS: This study provides further evidence for the stem cell character of ALDH1+ cells, here in benign breast tissue of cancer and non-cancer patients throughout non-lactating adult life, and contributes evidence of benign stromal ALDH1+ cells. The distribution of ductular ALDH1+ stem cells appears to be influenced by hormonal status.

Diagnosis of intraurothelial neoplasia. Interobserver variation and the value of individual histopathologic attributes.

OBJECTIVE: To determine interobserver variation in histopathologic diagnosis of carcinoma in situ (CIS) and dysplasia (collectively intraurothelial neoplasia [IUN]) of the bladder and identify histomorphologic features important for diagnosis. STUDY DESIGN: A total of 272 consecutive bladder tissue samples were re-evaluated blindly by two general pathologists and one uropathologist for IUN. Discrepancies were resolved jointly. Fifteen histopathologic attributes were evaluated for prediction of diagnosis. Followup revealed recurrence and progression rates for each diagnostic category. RESULTS: Thirty-six percent of specimens contained no evaluable flat mucosa; 51% percent of specimens from papillary urothelial neoplasia (PUN) cases showed CIS. General pathologists detected 56-69% of CIS and 8-42% of dysplasia. Histopathologic features most predictive for CIS were nuclear size, variation in nuclear shape, loss of maturation, loss of polarity, and architectural disorder. None of these individually or in combination exceeded general pathologists' diagnostic accuracy. IUN was not predictive of recurrence or progress. CONCLUSION: Using material mostly consisting of flat mucosa gratuitously provided in PUN resection specimens, IUN carries no prognostic value. General histopathologists detect IUN poorly to moderately, and the five most discriminatory histomorphologic features are insufficient for diagnosis. Interobserver agreement for dysplasia is dismal. Absent flat mucosa in PUN resections predicts recurrence.

Simplification of grading papillary urothelial neoplasia using a reduced set of diagnostic features.

OBJECTIVE: To determine whether a reduced set of the histopathologic features used in internationally accepted classifications is capable of accurately grading papillary urothelial neoplasms (PUN). STUDY DESIGN: All surgical specimens from urinary bladders received during a 2-year period were reexamined by an expert uropathologist for assessing the accuracy of original nonexpert PUN grading and staging. Thirteen histopathologic features entailing 32 attributes were evaluated with regard to prediction of expert grade. Patients were followed for 35-59 months (mean, 47). RESULTS: A total of 88 PUN specimens could be analyzed completely including follow-up specimens. Agreement between original and expert grade was 71% for low-grade and 87% for high-grade PUN, with overall kappa = 0.53. The histomorphologic features most predictive of expert grade were architectural disorder, variability of nuclear enlargement, and absence of umbrella cells. Neither individual histomorphologic attributes nor their combinations were as predictive of expert pathologist grade as original diagnoses. CONCLUSION: Improvements in PUN grading and prognostication are not likely to be accomplished by only reducing the number of histomorphologic features currently recommended by the World Health Organization and International Society of Urological Pathology.

The sensitivity of fluorescent-light cystoscopy for the detection of carcinoma in situ (CIS) of the bladder: a meta-analysis with comments on gold standard.

What's known on the subject? and What does the study add? Fluorescent-light cystoscopy has a high sensitivity, relative to that of white light cystoscopy, for carcinoma in situ of the bladder. However, this systematic review reveals that the absolute sensitivity is unknown due to the absence of proper gold standard which is microscopic examination of whole bladders. • A literature search was conducted to identify peer-reviewed study reports on the sensitivity of fluorescent-light cystoscopy (FLC) for the detection of carcinoma in situ (CIS) of the bladder. • Data from 16 original studies comprising 1503 patients were pooled. • The claimed sensitivity of FLC for detecting patients with CIS using the most commonly reported intravesical agents 5-aminolevulinic acid or hexaminolevulinic acid was 92.4%, while that of white-light cystoscopy (WLC) was 60.5%. The two agents did not differ significantly for sensitivity. • It must be pointed out that a 'gold standard' is lacking in FLC studies. • The occurrence of CIS of the bladder can only be established by the pathological examination of whole bladders. The true sensitivities of various modes of cystoscopy for detecting CIS can be revealed if patients scheduled for cystectomy are first examined with WLC, FLC, and optionally random biopsies. • The absolute sensitivity of FLC for detecting CIS of the bladder is not yet known.

The value of the UroVysion assay for surveillance of non-muscle-invasive bladder cancer.

OBJECTIVE: Patients with non-muscle-invasive bladder cancer are traditionally followed by repeat cystoscopy and urine cytology. A fluorescence in situ hybridisation technique called UroVysion (UV) is now available for clinical diagnosis of urothelial cancer cells. The aim of the present study was to compare UV analysis with routine follow-up methods. METHODS: We studied an unselected cohort of patients undergoing cystoscopy follow-ups at two Swedish centres in 2004-2005. All patients were investigated by cystoscopy, cytology, and UV assay. The UV assay was evaluated with regards to sensitivity, specificity, and positive predictive value for tumour recurrence. RESULTS: In all, 159 cases were analysed. UV had a 30% overall sensitivity for the 27 biopsy-proven recurrences and 70% sensitivity for high-risk tumours (pT1 and carcinoma in situ [CIS]). The specificity of UV was 95%. UV detected all six CIS cases in the study and was predictive in two additional patients who developed CIS within 1 yr of inclusion. Cytology was positive in four of those eight CIS cases and atypical in the other four. CONCLUSIONS: The UV assay cannot replace cystoscopy for surveillance of patients with non-muscle-invasive bladder cancer, but it may be valuable as a supplement to traditional measures for detecting CIS. Before any conclusions can be drawn regarding the efficacy of novel markers of bladder cancer, they must be studied in bladder cancer patients undergoing endoscopic surveillance.

Low frequency of defective mismatch repair in a population-based series of upper urothelial carcinoma.

BACKGROUND: Upper urothelial cancer (UUC), i.e. transitional cell carcinomas of the renal pelvis and the ureter, occur at an increased frequency in patients with hereditary nonpolyposis colorectal cancer (HNPCC). Defective mismatch repair (MMR) specifically characterizes HNPCC-associated tumors, but also occurs in subsets of some sporadic tumors, e.g. in gastrointestinal cancer and endometrial cancer. METHODS: We assessed the contribution of defective MMR to the development of UUC in a population-based series from the southern Swedish Cancer Registry, through microsatellite instability (MSI) analysis and immunohistochemical evaluation of expression of the MMR proteins MLH1, PMS2, MSH2, and MSH6. RESULTS: A MSI-high phenotype was identified in 9/216 (4%) successfully analyzed patients and a MSI-low phenotype in 5/216 (2%). Loss of MMR protein immunostaining was found in 11/216 (5%) tumors, and affected most commonly MSH2 and MSH6. CONCLUSION: This population-based series indicates that somatic MMR inactivation is a minor pathway in the development of UUC, but tumors that display defective MMR are, based on the immunohistochemical expression pattern, likely to be associated with HNPCC.