Monoclonal antibodies against 3-deoxy-alpha-D-manno-oct-2-ulosonic acid (Kdo) and D-glycero-alpha-D-talo-oct-2-ulosonic acid (Ko)

Monoclonal antibodies (mAbs) were obtained after immunization of mice with neoglycoconjugates containing as a ligand the disaccharide Kdo(2-->4)Ko or Ko(2-->4)Kdo, representing structural elements of the core region of lipopolysaccharides (LPSs) from Acinetobacter haemolyticus and Burkholderia cepacia, respectively. One antibody, S67-9, bound with high specificity to Ko(2-->4)Kdo-BSA showing no cross reactivity with Kdo(2-->4)Kdo-BSA and the other antigens tested. A second mAb, S68-12, bound preferentially to Kdo(2-->4)Ko-BSA but cross reacted with Ko(2-->4)Kdo-BSA and Kdo(2-->4)Kdo-BSA. A third mAb, S67-27, was found to bind Kdo monosaccharide. Although mAbs S67-9 and S68-12 did not bind to LPS of Burkholderia or Acinetobacter as expected, the mAbs will be useful tools in studying the biosynthesis of LPS containing Ko.     

alphaV integrin promotes in vitro and in vivo survival of cells in metastatic melanoma

The expression of integrin alphaV subunit on 4 melanoma-derived cell lines (A2058, SK-mel-5, WM-115 and WM-266-4) was analyzed. WM-115 cells, which originate from a primary tumor, were negative, whereas all 3 metastasis-derived lines had high levels of alphaV. To study alphaV integrins in the survival of melanoma cells, we developed a novel strategy that is exempt from extracellular inhibitors of ligand binding, which can activate integrin signaling and have integrin-independent effects on apoptosis. A recombinant adenovirus was used to transfer cDNA coding for a single-chain intracellular anti-alphaV integrin antibody into the melanoma cells. Anti-alphaV integrin adenovirus effectively inhibited the cell surface expression of alphaV integrins. In cell culture experiments, the depletion of alphaV integrins detached cells from extracellular matrix and induced apoptosis. Moreover, it prevented WM-266-4 cells from forming tumors in severe combined immunodeficiency mice but it could not prevent the growth of tumors that were formed by alphaV-negative WM-115 cells. Our results indicate that in primary melanomas there are cells that survive without alphaV integrins, whereas during the progression of disease cells can develop a dependency on these receptors. Furthermore, the data oppose the possibility that in melanoma cells apoptosis could occur due to direct activation of caspases by ligand-free alphaV integrins on the cell surface.     

Factors influencing the exercise behavior of adults with physical disabilities

PURPOSE: Examine the theorized associations of transtheoretical model (TTM) of behavior change constructs (behavioral and cognitive processes of change, decisional balance, and self-efficacy), along with exercise barriers, by stage of change for exercise behavior among individuals with physical disabilities. METHODS: Cross-sectional survey of 322 adults with physical disabilities residing in the United States. Most participants (84.3%) used some form of assistive device (e.g., artificial limb, wheelchair), were female (62.1%), and Caucasian (91.9%). The mean age of participants was 52.5 yr (SD = 13.9). Participants completed and returned questionnaires for each TTM construct, along with an exercise barriers measure. RESULTS: In univariate analyses, all constructs were significantly (P < 0.001) associated with the stages of change for exercise behavior, except for dramatic relief (P > 0.005). The largest portion of variance was derived from counter conditioning (eta = 0.45), followed by the five behavioral processes of change combined (eta = 0.40), self-liberation (eta = 0.31), self-efficacy (eta = 0.30), and self-reevaluation (eta = 0.28). Direct discriminant function (multivariate) analysis revealed four discriminant functions which accounted for 71.0% (P < 0.001), 20.9% (P < 0.001), 6.3% (P < 0.05), and 1.8% (P = 0.62), respectively, of the between-group (stage of change) variability. The overall stage of change classification accuracy was 70.8%. CONCLUSION: This was the first study to examine the stages of change for exercise behavior among adults with physical disabilities on the basis of the full TTM and exercise barriers. Overall, the results are in general agreement with existing evidence among nondisabled populations. This provides further cross-sectional support for the internal and external validity of TTM and exercise barriers among a unique and understudied population segment.     

The incidence and etiology of postlaryngectomy pharyngocutaneous fistulae

BACKGROUND: The pharyngocutaneous fistula is troublesome complication after total laryngectomy. Despite a large number of studies, there is still disagreement on factors predisposing to this complication. METHODS: A retrospective analysis of pharyngocutaneous fistulas in 133 patients in whom total laryngectomy was performed. RESULTS: Fistulas were found in 15% of the patients. Spontaneous closure was noted in 80%. Simultaneous laryngectomy and partial pharyngectomy or neck dissection increased the risk of fistula formation. Preoperative irradiation, short interval between radiotherapy and operation, and cobalt/roentgen radiation instead of photons predispose to this complication. The fistulas appeared earlier, and the sizes of fistulas were significantly larger in patients with previous irradiation than those in patients with no preoperative irradiation. CONCLUSIONS: Postoperative pharyngocutaneous fistulas significantly increase patients' morbidity and hospital stay. Good surgical technique and postoperative treatment should be paid attention to patients with an increased risk of pharyngocutaneous fistula formation.     

High levels of stromal hyaluronan predict poor disease outcome in epithelial ovarian cancer

Several malignant tumors accumulate hyaluronan, a matrix component suggested to promote cancer cell migration and growth. To explore the potential clinical importance of this concept, we assessed the hyaluronan levels in epithelial ovarian cancer. A biotinylated affinity probe specific for hyaluronan was prepared and applied to histological sections of 309 epithelial ovarian cancers and 45 matched metastatic lesions. The staining was scored according to the percentage area of strong hyaluronan signal of total peri- and intratumoral stroma as low (<35%), moderate (35-75%), or high (>75%). Low, moderate, and high levels of stromal hyaluronan were observed in 95, 116, and 98 carcinomas, respectively. The high stromal hyaluronan level was significantly associated with poor differentiation, serous histological type, advanced stage, and large primary residual tumor, whereas it was not correlated with high CD44 expression on cancer cells. The 5-year outlook of the disease deteriorated with increasing stromal hyaluronan levels for both overall (45% versus 39% versus 26%; P = 0.002) and recurrence-free (66% versus 56% versus 40%; P = 0.008) survival. High levels of stromal hyaluronan were more frequent in metastatic lesions than in primary tumors (z = -3.9; P = 0.0001). In Cox's multivariate analyses, high level of stromal hyaluronan was an independent prognostic factor in all patients, as well as in stage-specific subgroups. These results suggest that stromal hyaluronan accumulation may be a powerful enhancer of tumor progression and, as such, provides a novel, independent prognostic marker and a potential target of therapy.     

p21WAF1 expression in invasive breast cancer and its association with p53, AP-2, cell proliferation,and prognosis

AIMS: To evaluate the expression and prognostic relevance of p21(WAF1) in breast cancer and to investigate its association with p53, activator protein 2 (AP-2), and cell proliferation (as assessed by Ki-67 expression). METHODS: p21(WAF1) expression was analysed immunohistochemically in a large prospective, consecutive series of 420 patients with breast cancer diagnosed and treated between 1990 and 1995 at Kuopio University Hospital, Kuopio, Finland. Inter-relations between p21(WAF1) expression and p53, AP-2, and Ki-67 were evaluated. The expression of p21(WAF1) was also compared with clinicopathological parameters and the patients' survival. RESULTS: In general, nuclear p21(WAF1) expression was low in carcinomas (median, 2.5%; range, 0-70%). Expression was lowest in lobular carcinomas (chi(2) = 7.4; p = 0.025). p21(WAF1) positive tumours were more often p53 positive (chi(2) = 4.2; p = 0.041) but expression of p21(WAF1) did not correlate with AP-2 expression or Ki-67 in the whole patient group. In addition, the combined expression of p21 and p53 was not associated with AP-2 expression. High nuclear p21(WAF1) positivity (n = 160; 38%) was associated with poor differentiation (chi(2) = 8.1; p = 0.017). In the univariate analyses, p21(WAF1) expression had no prognostic value for predicting breast cancer related survival (BCRS) or recurrence free survival (RFS) in the whole patient group or in the subgroups investigated. However, in postmenopausal patients with lymph node metastases, and oestrogen receptor (ER) and/or progesterone receptor (PR) positive tumours, high p21(WAF1) expression predicted response to adjuvant hormonal treatment with antioestrogens. In the univariate analysis, the significant factors for predicting BCRS were Ki-67 expression, stage, lymph node status, histological grade, ER and PR status, and those for RFS were Ki-67 expression, stage, and lymph node status. In the multivariate analysis, the independent predictors of shorter BCRS were high cell proliferation activity measured by Ki-67 expression (p < 0.001), advanced stage (p < 0.001), and poor differentiation (p = 0.048). Shorter RFS was independently predicted by high cell proliferative activity (p < 0.001) and advanced stage (p < 0.001). CONCLUSIONS: The regulation of p21(WAF1) seems to occur independently of p53 or AP-2 and analysing p21(WAF1) expression provided no prognostic information for patients with breast cancer.     

Versican in epithelial ovarian cancer: relation to hyaluronan, clinicopathologic factors and prognosis

Versican, a proteoglycan previously reported to increase in other malignant tumours, was studied immunohistochemically in 299 primary epithelial ovarian cancers, their 43 metastases and 6 normal ovaries to evaluate its prognostic value and relation to hyaluronan, another extracellular matrix molecule increased in cancer and a binding partner of versican. The stainings were scored according to the area percentage of strong versican signal of total peri- and intratumoural stroma as low (<15%) or high (>or=15%). Epithelial staining of the tumours was scored as positive or negative. Low and high area percentage of strong stromal versican staining were observed in 133 and 166 carcinomas, respectively. A low area percentage of strong stromal versican staining correlated with mucinous histology (p = 0.019) and early International Federation of Gynecologists and Obstetritians (FIGO) stage (p < 0.0005), whereas a high percentage was associated with reduced 5-year survival rate of the patients (44% vs. 32%; p = 0.032). Versican was associated with the cancer cells in 151 tumours and correlated with clear cell histology (p < 0.0005), early FIGO stage (p = 0.049) and increased recurrence-free survival (63% vs. 47%; p = 0.032). However, in Cox's multivariate analyses with the conventional prognostic factors included, neither stromal nor cancer cell-associated versican reached a significant prognostic value. Versican is thus enriched in the malignant stroma surrounding and promoting the growth of ovarian cancer, probably acting with hyaluronan, and associates with unfavourable prognosis but does not constitute an independent indicator of patient survival.     

Tissue inhibitor of metalloproteinases-3 induces apoptosis in melanoma cells by stabilization of death receptors

Tissue inhibitors of metalloproteinases (TIMPs) are important regulators of matrix metalloproteinase (MMP) and adamalysin (ADAM) activity. We have previously shown that adenovirally expressed tissue inhibitor of metalloproteinases-3 (TIMP-3) induces apoptosis in melanoma cells and inhibits growth of human melanoma xenografts. Here, we have studied the role of death receptors in apoptosis of melanoma cells induced by TIMP-3. Our results show, that the exposure of three metastatic melanoma cell lines (A2058, SK-Mel-5, and WM-266-4) to recombinant TIMP-3, N-terminal MMP inhibitory domain of TIMP-3, as well as to adenovirally expressed TIMP-3 results in stabilization of tumor necrosis factor receptor-1 (TNF-RI), FAS, and TNF-related apoptosis inducing ligand receptor-1 (TRAIL-RI) on melanoma cell surface and sensitizes these cells to apoptosis induced by TNF-alpha, anti-Fas-antibody and TRAIL. Stabilization of death receptors by TIMP-3 results in activation of caspase-8 and caspase-3, and subsequent apoptosis is blocked by specific caspase-8 inhibitor (Z-IETD-FMK) and by pan-caspase inhibitor (Z-DEVD-FMK). Adenovirus-mediated expression of TIMP-3 in human melanoma xenografts in vivo resulted in increased immunostaining for TNF-RI, FAS, and cleaved caspase-3, and in apoptosis of melanoma cells. Taken together, these results show that TIMP-3 promotes apoptosis in melanoma cells through stabilization of three distinct death receptors and activation of their apoptotic signaling cascade through caspase-8.     

Evaluation of p21WAF1/CIP1 and cyclin D1 expression in the progression of superficial bladder cancer

Immunoreactivity of p21^WAF1/CIP1 and cyclin D₁ proteins was assessed in a cohort of 207 patients with superficial (pTa-pT₁) bladder cancer followed up for a mean of 4.9 years. The results of the immunostainings were compared with T category, WHO grade, tumor cell proliferation rate (MIB-1 score), the expressions of p53 and bcl-2 as well as survival. Sixty-eight percent and 75% of the tumors were p21^WAF1/CIP1 positive (≥5% of cells positive) and cyclin D₁ positive (≥10% of cells positive), respectively. The p21^WAF1/CIP1 expression was related to cyclin D₁ immunolabelling (P < 0.001) but not to the other variables studied. The expression of cyclin D₁ was inversely associated with T category (P=0.001), WHO grade (P=0.006), MIB-1 score (P=0.014), p53 expression (P=0.001), and bcl-2 (P=0.011) immunoreactivity. In univariate analysis, T category (P=0.0001), WHO grade (P < 0.0001), MIB-1 score (P < 0.0001), bcl-2 (P=0.0092), p53 (P=0.0016) and p21^WAF1/CIP1 (P=0.009) expressions were significant prognostic factors with regard to tumor progression, whereas cyclin D₁ was without any prognostic significance (P=0.1). Out of 123 p21 positive tumors 21 progressed, whereas only 2 out of 58 p21 negative tumors progressed. In multivariate analysis, the MIB-1 score was the only independent predictor of cancer-specific survival (P=0.03), whereas tumor grade (P=0.002) and cyclin D₁ expression (P=0.04) were independent predictors of tumor recurrence. Only the WHO grade (P=0.04) retained its prognostic value indicating the risk of progression. We suggest that in superficial bladder cancer p21^WAF1/CIP1 and cyclin D₁ immunohistochemistry provide no additional prognostic information compared with already established prognostic factors for predicting the risk of progressive disease. Received: 13 September 1999 / 22 March 2000