ALDH1 expression indicates chemotherapy resistance and poor outcome in node-negative rectal cancer.

The cancer stem cell marker aldehyde dehydrogenase 1 (ALDH1) associates with treatment resistance and adverse outcome in several human cancers. We studied ALDH1 expression in rectal cancer, with special emphasis on its association with treatment response and disease outcome. Immunohistochemical staining for ALDH1 was conducted for 64 biopsies and 209 operative samples from rectal cancer patients treated with short- (n = 89) or long-course (n = 46) (chemo)radiotherapy plus surgery, or with surgery only (n = 74). The staining results were compared to clinicopathological variables, tumor regression grade (TRG) and disease outcome. Nuclear ß-catenin expression pattern was analyzed from 197 operative samples. Positive ALDH1 expression was present in 149 operative samples (71%), correlating with deficient nuclear ß-catenin regulation (P = .018). In a pairwise comparison of respective biopsy and operative samples, ALDH1 expression remained stable or increased after preoperative (chemo)radiotherapy in most of the cases, while it decreased in few cases only (P = .02 for positive/negative category; P <.001 for intensity). ALDH1 expression did not, however, relate to tumor regression grade. In node-negative rectal cancer, ALDH1 expression was an independent predictor of short disease-free and disease-specific survival (P = .044; P = .049), specifically among patients treated with adjuvant chemotherapy. We conclude that ALDH1 associates with deregulated ß-catenin signaling, supporting the role of ALDH1 in rectal cancer stemness. ALDH1 expression relates to poor outcome in early stage rectal cancer, a group where new prognostic tools are particularly needed, and may indicate chemo- and radioresistance.

Securin identifies a subgroup of patients with poor outcome in rectal cancer treated with long-course (chemo)radiotherapy.

BACKGROUND: Securin is an oncogene with functions in cell proliferation, tumour initiation and progression. Its prognostic value in rectal cancer is somewhat unknown. Accordingly, we studied securin expression together with Ki-67 in rectal cancer in relation to preoperative (chemo)radiotherapy (RT) and disease outcome. MATERIAL AND METHODS: Biopsies (n = 65 for securin; n = 57 for Ki-67) and operative specimens (n = 207) from 211 patients treated with short-course RT (n = 87), long-course RT (n = 54) or surgery only (n = 70) were studied with immunohistochemistry (IHC) for securin and Ki-67 expression. In the long-course RT group, 45 patients received chemotherapy (5-fluorouracil or capecitabine) concomitantly with RT. The results of IHC were related to clinicopathological variables, disease outcome and tumour regression grade (TRG) after long-course RT. RESULTS: Both markers showed significant reduction after RT (p < 0.001). No differences in expression was seen in the long-course RT group between the patients with or without concomitant chemotherapy (p = 0.23 for securin; p = 0.31 for Ki-67). Low Ki-67 expression, but not that of securin, in operative specimens was significantly related to excellent TRG (p = 0.02 for Ki-67; p = 0.21 for securin). In univariate survival analysis, excellent TRG predicted longer disease-specific survival (DSS; p = 0.03). In multivariate Cox analysis, high securin expression after long-course (chemo)RT was an independent predictor of shorter DSS (p = 0.036) together with patient age (p = 0.043) and disease recurrence (local or distant; p = 0.009), whereas no similar appearance was seen in other treatment groups. CONCLUSION: Securin expression in rectal cancer is significantly reduced after RT. High securin expression and poor TRG after long-course (chemo)RT are indicators of unfavourable disease outcome.

Prognostic evaluation of COX-2 expression in renal cell carcinoma.

BACKGROUND: Prognosis of renal cell carcinoma (RCC) differs within the same stage and grade. Our aim was to investigate the incidence of COX-2 in primary RCC tumors at different stages according to the occurrence of metastasis, and the impact of this biomarker on the survival of RCC patients. PATIENTS AND METHODS: The cytoplasmic/membranous COX-2 protein expression was examined by immunohistochemistry in RCC tumors from 102 patients. The patients were divided into those with: no metastasis during 7.5 years' follow-up (nm), no metastasis at the time of nephrectomy but who later developed metastases (lm), and those with metastasis at presentation (pm). The immunoreactivity of COX-2 was classified as none (absent/weak intensity in fewer than 10% of the cancer cells), low (weak intensity in over 10% of the cancer cells) or high immunostaining (strong intensity in the majority of the cancer cells). In addition p53 and Ki-67 immunostaining was also assessed in tumors. RESULTS: Percentages of COX-2 reaction were (no/low/high): 78/16/7 in the nm, 53/28/19 in the lm, 92/8/0 in the pm groups (p=0.014). Median metastasis-free survival was shorter in lm patients with COX-2-negative tumors when compared to those with COX-2-positive ones (15 vs. 46 months; p=0.020). Median overall survival was shorter in pm/lm patients with COX-2-negative tumors when compared to those with COX-2-positive ones (28 vs. 94 months; p=0.027), and with COX-2-negative/Ki-67-positive tumors when compared to COX-2-positive/Ki-67-negative ones (19 vs. 97 months; p=0.004). Findings for patients with COX-2-negative/p53-positive tumors were similar, with shorter survival compared to those with COX-2-positive/p53-negative ones (19 vs. 97; p=0.006). CONCLUSION: COX-2 protein expression is associated with slow development of metastases, and favourable prognosis in metastatic RCC.

Serum angiogenin levels predict treatment response in patients with stage IV melanoma.

This work was conducted to find out new potential serum markers and study their role as predictive factors in patients with metastatic melanoma. Serum samples from 68 patients with stage IV malignant melanoma were collected just before current treatment and screened for 79 different cytokines by using a multi-cytokine array. Angiogenin, which is a protein capable of promoting angiogenesis, was found to be markedly elevated among a sub-group of patients with progressive disease (PD) and thus was subjected to further analysis. The mean serum angiogenin level was 270 ng/ml and the median 236 ng/ml (STD 163 ng/ml). Concentrations were significantly higher among men than in women (P = 0.031), whereas patient's age, site of the primary tumour, Clark's or Breslow's classifications were not associated with angiogenin levels. Patients with only lymph node metastases had markedly lower angiogenin levels than those with metastases at other sites (P = 0.05). High angiogenin levels were significantly (P = 0.015; Kruskal-Wallis) associated with poor treatment response with chemoimmunotherapy. Treatment-related survival (TRS) was shorter (10 months) in patients with above-median values than in those with below-median levels (19 months, P = NS). Cox multivariate regression model was used to control for the confounding by the classical prognostic factors of melanoma (age, sex, disease burden, performance score, site of metastases). Disease burden was the only variable that remained in the model as a significant independent predictor of TRS (P = 0.044). These data suggest that serum angiogenin levels might be of predictive value in the evaluation of treatment response for patients with stage IV melanoma.

Serum VEGF-C is associated with metastatic site in patients with malignant melanoma.

Vascular endothelial growth factor-C (VEGF-C) is involved in lymphatic metastatic spread. Metastatic site is a prognostic factor in melanoma. We assessed whether serum levels of VEGF-C are associated with metastatic sites or prognosis in patients treated for stage IV melanoma. The study included 64 patients, who received dacarbazine or four-drug chemotherapy (dacarbazine, vincristine, bleomycin and lomustine; BOLD) both combined with interferon-alfa. Serum samples for VEGF-C were analyzed by ELISA. The patients (n =22) with only skin and subcutaneous metastases had significantly lower mean VEGF-C levels (1 643 pg/ml) then the patients (n =42) with other distant metastases (2 584 pg/ml, Mann-Whitney, p =0.033). VEGF-C levels above the median (1 590 pg/ml) were significantly related to deep lymph node involvement (OR 3.763; 95% CI 1.038 - 13.646, p =0.034). There were no other significant associations between VEGF-C levels and tumour burden, nor were the levels significantly related to the response to therapy or survival. Those eight patients, who had received previous adjuvant IFN-alfa therapy had lower mean VEGF-C levels (1 738 pg/ml) as compared to those 56 patients without previous IFN-alfa therapy (2 335 pg/ml, ANOVA, p =0.026). This is the first study exploring serum VEGF-C in melanoma. VEGF-C might be involved in the deep lymphatic dissemination and progression of melanoma metastasis.

The prognostic role of CD4+ and CD8+ lymphocytes during chemoimmunotherapy in metastatic melanoma.

We have observed that an early increase in the CD4+/CD8+ ratio of metastatic melanoma patients during chemoimmunotherapy is the most favourable independent prognostic factor. In this study, 87 patients with metastatic melanoma were monitored for peripheral blood lymphocyte subsets (CD4+ and CD8+) before and during chemoimmunotherapy (dacarbazine, vinblastine, lomustine and bleomycin or dacarbazine alone plus interferon-alpha) to confirm our previous observation. Blood samples were systematically obtained from patients who received either of these chemoimmunotherapies. The frequencies of peripheral blood lymphocyte subsets were monitored by flow cytometry using monoclonal antibodies OKT4 (CD4+, T-helper cells) and OKT8 (CD8+, T-suppressor cells). The overall response rate was 46.5%, and the median overall survival was 9.3 months. Patients with pre-treatment CD4+ levels above the mean level, who later responded to therapy, had a median survival of 28.1 months vs. 10.2 months for responders with low pre-treatment CD4+ levels (P=0.053, log-rank test). Responders with decreasing CD8+ levels had a median survival of 27.8 months vs. 10.8 months for responders with increasing CD8+ levels (P=0.04, log-rank test). Similarly, responding patients with an increasing CD4+/CD8+ ratio had a median survival of 28.1 months vs. 10.5 months for those with decreasing ratios (P=0.002, log-rank test). Non-responders showed no difference in median survival irrespective of low or high pre-treatment CD4+ lymphocytes, increasing or decreasing CD8+ levels, or increasing or decreasing CD4+/CD8+ ratios. This follow-up study confirms that the monitoring of CD4+ and CD8+ lymphocytes may provide important predictive and prognostic information in metastatic melanoma patients receiving chemoimmunotherapy.

New prognostic factors and developing therapy of cutaneous melanoma.

The multiple molecular alterations underlying the neoplastic process and clinical characteristics of cutaneous melanoma are currently under intensive investigation. Recent studies have demonstrated that the levels of melanoma-associated proteins in tumor tissue or in patient serum can serve as new markers to predict disease outcome. Similarly, the expression of thousands of genes in melanoma tumors can be surveyed simultaneously using DNA arrays, allowing molecular profiling of individual tumors, which gives the possibility of classifying melanomas based on their biological diversity. Large clinical studies have also identified multiple prognostic factors, such as tumor ulceration, and led to development of a new, more precise melanoma staging system, which emphasizes the biological characteristics of the primary disease. These new findings may have an important role in earlier measurement of the clinical response and provide a basis for tailored melanoma therapy, the development of which will also be discussed in this review.