Overexpression of CD44: a useful independent predictor of prognosis in patients with colorectal carcinomas

Genome-Wide Analysis of lncRNA-mRNA Co-Expression Networks in CD133+/CD44+ Stem-like PDAC Cells

Pancreatic ductal adenocarcinoma (PDAC), the second most prevalent gastrointestinal malignancy and the most common type of pancreatic cancer is linked with poor prognosis and, eventually, with high mortality rates. Early detection is seldom, while tumor heterogeneity and microarchitectural alterations benefit PDAC resistance to conventional therapeutics. Although emerging evidence suggest the core role of cancer stem cells (CSCs) in PDAC aggressiveness, unique stem signatures are poorly available, thus limiting the efforts of anti-CSC-targeted therapy. Herein, we report the findings of the first genome-wide analyses of mRNA/lncRNA transcriptome profiling and co-expression networks in PDAC cell line-derived CD133+/CD44+ cells, which were shown to bear a CSC-like phenotype in vitro and in vivo. Compared to CD133-/CD44- cells, the CD133+/CD44+ population demonstrated significant expression differences in both transcript pools. Using emerging bioinformatic tools, we performed lncRNA target coding gene prediction analysis, which revealed significant Gene Ontology (GO), pathway, and network enrichments in many dyregulated lncRNA nearby (cis or trans) mRNAs, with reported involvement in the regulation of CSC phenotype and functions. In this context, the construction of lncRNA/mRNA networks by ingenuity platforms identified the lncRNAs ATF2, CHEK1, DCAF8, and PAX8 to interact with "hub" SC-associated mRNAs. In addition, the expressions of the above lncRNAs retrieved by TCGA-normalized RNAseq gene expression data of PAAD were significantly correlated with clinicopathological features of PDAC, including tumor grade and stage, nodal metastasis, and overall survival. Overall, our findings shed light on the identification of CSC-specific lncRNA signatures with potential prognostic and therapeutic significance in PDAC.

The role of CD44 in pathological angiogenesis

Angiogenesis is required for normal development and occurs as a pathological step in a variety of disease settings, such as cancer, ocular diseases, and ischemia. Recent studies have revealed the role of CD44, a widely expressed cell surface adhesion molecule, in promoting pathological angiogenesis and the development of its associated diseases through its regulation of diverse function of endothelial cells, such as proliferation, migration, adhesion, invasion, and communication with the microenvironment. Conversely, the absence of CD44 expression or inhibition of its function impairs pathological angiogenesis and disease progression. Here, we summarize the current understanding of the roles of CD44 in pathological angiogenesis and the underlying cellular and molecular mechanisms.

MiR-145 in cancer therapy resistance and sensitivity: A comprehensive review

MircoRNA (miRNA) are a group of small, non–coding, regulatory RNA with an average length of approximately 22 nucleotides, which mostly modulate gene expression post–transcriptionally through complementary binding to the 3ʹ‐untranslated region (3ʹ‐UTR) of multiple target genes. Emerging evidence has shown that miRNA are frequently dysregulated in a variety of human malignancies. Among them, microRNA‐145 (miR‐145) has been increasingly identified as a critical suppressor of carcinogenesis and therapeutic resistance. Resistance to tumor therapy is a challenge in cancer treatment due to the daunting range of resistance mechanisms. We reviewed the status quo of recent advancements in the knowledge of the functional role of miR‐145 in therapeutic resistance and the tumor microenvironment. It may serve as an innovative biomarker for therapeutic response and cancer prognosis.

Hypoxic tumor microenvironment: Implications for cancer therapy

IMPACT STATEMENT

Hypoxia contributes to tumor aggressiveness and promotes growth of many solid tumors that are often resistant to conventional therapies. In order to achieve successful therapeutic strategies targeting different cancer types, it is necessary to understand the molecular mechanisms and signaling pathways that are induced by hypoxia. Aberrant tumor vasculature and alterations in cellular metabolism and drug resistance due to hypoxia further confound this problem. This review focuses on the implications of hypoxia in an inflammatory TME and its impact on the signaling and metabolic pathways regulating growth and progression of cancer, along with changes in lymphangiogenic and angiogenic mechanisms. Finally, the overarching role of hypoxia in mediating therapeutic resistance in cancers is discussed.

Acquired Resistance to Alectinib in ALK-Rearranged Lung Cancer due to ABCC11/MRP8 Overexpression in a Clinically Paired Resistance Model

Alectinib is used as a first-line treatment for anaplastic lymphoma kinase (ALK)-rearranged non-small cell lung cancer (NSCLC). Whereas other ALK inhibitors have been reported to be involved in resistance to ATP-binding cassette (ABC) transporters, no data are available regarding the association between resistance to alectinib and ABC-transporters. To investigate whether ABC-transporters contribute to alectinib resistance, ABC-transporter expression in alectinib-resistant cell lines derived from a patient with ALK-rearranged NSCLC and from H2228 lung cancer cells was evaluated and compared with that in each parent cell type. ATP-binding cassette subfamily C member 11 (ABCC11) expression was significantly increased in alectinib-resistant cell lines compared with that in alectinib-sensitive lines. ABCC11 inhibition increased sensitivity to alectinib in vitro ABCC11-overexpressing cells were established by transfection of an ABCC11 expression vector into H2228 cells, while control cells were established by transfecting H2228 cells with an empty vector. ABCC11-overexpressing cells exhibited decreased sensitivity to alectinib compared with that of control cells in vitro Moreover, the tumor growth rate following alectinib treatment was higher in ABCC11-overexpressing cells than that in control cells in vivo In addition, the intracellular alectinib concentration following exposure to 100 nmol/L alectinib was significantly lower in the ABCC11-overexpressing cell line compared with that in control cells. This is the first preclinical evidence showing that ABCC11 expression may be involved in acquired resistance to alectinib.

The Prognostic and Clinical Value of CD44 in Colorectal Cancer: A Meta-Analysis

Background: CD44 is widely used as a putative cancer stem cells (CSCs) marker for colorectal cancer (CRC). However, the prognostic role of CD44 in CRC remains controversial. Methods: We performed a systematic review and meta-analysis to evaluate the association of various CD44 isoforms and overall survival (OS) and clinicopathological features of CRC patients. Results: A total of 48 studies were included in the meta-analysis. Total CD44 isoforms overexpression was significantly correlated with worse OS of patients with CRC (HR = 1.32, 95% CI = 1.08-1.61, P = 0.007). In a stratified analysis, a higher level of either CD44v6 or CD44v2 had an unfavorable impact on OS (HR_CD44v6 = 1.50, 95% CI = 1.10-2.14, P = 0.010; HR_CD44v2 = 2.93, 95% CI = 1.49-5.77, P = 0.002). Additionally, CD44 was shown to be associated with some clinicopathological features, such as lymph node metastasis (OR_CD44 = 1.56, 95% CI = 1.01-2.41, P = 0.044; OR_CD44v6 = 1.97, 95% CI = 1.19-3.26, P = 0.008; OR_{Total CD44 isoforms} = 1.57, 95% CI = 1.15-2.14, P = 0.004), distant metastasis (OR_CD44 = 2.90, 95% CI = 1.08-7.83, P = 0.035; OR_{Total CD44 isoforms} = 1.89, 95% CI = 1.02-3.53, P = 0.044). Moreover, a high level of CD44 showed a possible correlation with poor differentiation (OR_{Total CD44 isoforms} = 1.44, 95% CI = 1.00-2.08, P = 0.051), elevated level of CD44v6 tend to be correlated with tumor size (OR = 1.71, 95% CI = 0.99-2.96, P = 0.056). Conclusions: This meta-analysis demonstrated that CD44 overexpression might be an unfavorable prognostic factor for CRC patients and could be used to predict poor differentiation, lymph node metastasis and distant metastasis.

Sensitization of Drug Resistant Cancer Cells: A Matter of Combination Therapy

Cancer drug resistance is an enormous problem. It is responsible for most relapses in cancer patients following apparent remission after successful therapy. Understanding cancer relapse requires an understanding of the processes underlying cancer drug resistance. This article discusses the causes of cancer drug resistance, the current combination therapies, and the problems with the combination therapies. The rational design of combination therapy is warranted to improve the efficacy. These processes must be addressed by finding ways to sensitize the drug-resistant cancers cells to chemotherapy, and to prevent formation of drug resistant cancer cells. It is also necessary to prevent the formation of cancer progenitor cells by epigenetic mechanisms, as cancer progenitor cells are insensitive to standard therapies. In this article, we emphasize the role for the rational development of combination therapy, including epigenetic drugs, in achieving these goals.

Prognostic Significance of DNA Aneuploidy and p21ras Oncoprotein Expression in Colorectal Cancer and Their Role in the Determination of Treatment Modalities

The purpose of the present study was to investigate the prognostic significance of DNA ploidy, S-phase fraction and p21ras oncoprotein expression in patients with colorectal cancer and to correlate these factors with the clinical behavior of the tumors and their response to therapy. Of 79 patients with colorectal cancer 57% (45/79) had early stage disease. Forty-one percent (32/79) had aneuploid tumors while 30% (24/79) of the tumors had a high (>10%) S-phase fraction. p21ras oncoprotein expression was detected in 38% (30/79) of tumors. Patients with aneuploid tumors had a worse prognosis than patients with diploid tumors (p=0.0002). Similarly, patients with high S-phase fraction tumors had a shorter survival than those with low S-phase fraction tumors (p=0.005). No such difference was found between p21ras-positive and p21ras-negative tumor subgroups. In early stage colorectal cancer, aneuploidy was closely correlated with disease outcome (p=0.029). Early stage patients with diploid tumors who received radiotherapy and chemotherapy had a better prognosis than patients with aneuploid tumors. In conclusion, DNA ploidy is a significant and independent prognostic factor in colorectal cancer. Aneuploidy and genetic alteration of the p21ras oncoprotein are important in determining the biological aggressiveness of colorectal cancer. Furthermore, DNA ploidy may identify those subgroups of patients with early stage disease who may benefit from more aggressive treatment.

Cancer stem cell marker glycosylation: Nature, function and significance

Glycans are essential for the maintenance of normal biological function, with alterations in glycan expression being a hallmark of cancer. Cancer stem cells (CSCs) are a subset of cells within a tumour capable of self-renewal, cellular differentiation and resistances to conventional therapies. As is the case with stem cells, marker proteins present on the cell surface are frequently used to identify and enrich CSCs, with the expression of these markers statistical correlating with the likelihood of cancer recurrence and overall patient survival. As such CSC markers are of high clinical relevance. The majority of markers currently used to identify CSC populations are glycoproteins, and although the diverse biological roles for many of these markers are known, the nature and function of the glycan moiety on these glycoproteins remains to be fully elucidated. This mini-review summarises our current knowledge regarding the types and extent of CSC marker glycosylation, and the various roles that these glycans play in CSC biology, including in mediating cell adhesion, metastasis, evading apoptosis, tear shear resistance, tumour growth, maintaining pluripotency, self-renewal, trafficking, maintaining stability, maintaining enzymatic activity and aiding epithelial mesenchymal transitioning. Given that CSCs markers have multiple diverse biological functions, and are potentially of significant diagnostic and therapeutic benefit the search for new markers that are uniquely expressed on CSCs is vital to selectively target/identify this subset of cancer cells. As such we have also outlined how high-throughput lectin microarrays can be used to successfully profile the glycosylation status of CSC and to identify glyco-markers unique to CSCs.

Co-expression of CD133, CD44v6 and human tissue factor is associated with metastasis and poor prognosis in pancreatic carcinoma

The metastasis-related molecules CD133, CD44v6 and human tissue factor (TF) have been shown to be associated with tumor invasion and metastasis. This study aimed to determine whether co-expression of these three molecules was associated with metastasis and overall prognosis in pancreatic carcinoma. We analyzed the expression profiles of these three molecules by immunohistochemistry and evaluated the relationship of their expression profiles with metastasis and prognosis in 109 pancreatic carcinomas. The results showed that the expression levels of CD133, CD44v6 and TF were increased in pancreatic carcinoma. Co-expression of CD133, CD44v6 and TF (tri-expression) was also detected in pancreatic carcinoma. Clinical analysis showed that individual expression of CD133, CD44v6 or TF was associated with vessel invasion, lymph node metastasis and liver metastasis, while tri-expression was associated with lymph node metastasis. Survival analysis showed that patients with co-expression of CD133 and TF or tri-expression had lower and the lowest overall survival rates, respectively. Univariate analysis showed that T-factor, lymph node metastasis, TNM stage, and individual levels or tri-expression of CD133, CD44v6 and TF were survival risk factors. Multivariate analysis showed that tri-expression of CD133, CD44v6 and TF was an independent predictor of survival. These results suggest that overexpression of CD133, CD44v6 and TF is associated with pancreatic carcinoma metastasis. Tri-expression of these three molecules may be a useful predictor for pancreatic carcinoma prognosis.

Cancer drug resistance: an evolving paradigm

Resistance to chemotherapy and molecularly targeted therapies is a major problem facing current cancer research. The mechanisms of resistance to 'classical' cytotoxic chemotherapeutics and to therapies that are designed to be selective for specific molecular targets share many features, such as alterations in the drug target, activation of prosurvival pathways and ineffective induction of cell death. With the increasing arsenal of anticancer agents, improving preclinical models and the advent of powerful high-throughput screening techniques, there are now unprecedented opportunities to understand and overcome drug resistance through the clinical assessment of rational therapeutic drug combinations and the use of predictive biomarkers to enable patient stratification.

CD44: survival and metastasis in chondrosarcoma

OBJECTIVE

Recent studies have shown abnormal expression of CD44s and some of its isoforms in many human malignancies, but little is known about the presence of CD44 in chondrosarcoma. In this study the expression of CD44s and two variant isoforms was evaluated. It was assumed that abnormalities in these receptor proteins may be associated with clinical outcome of the patients.

METHOD

Thirty paraffin-embedded chondrosarcoma samples were immunostained with monoclonal antibodies for CD44s, CD44v5 and CD44v6. Two independent examiners who were unaware of the clinical status of the patients evaluated the immunohistochemical results. The percentage of CD44-positive cells was scored semiquantitatively. A rate of higher than 10% was considered as overexpression.

RESULTS

Among the 30 patients (median age 50 years) there were 22 conventional chondrosarcomas, two dedifferentiated chondrosarcomas, two extraskeletal chondrosarcomas, and one periostal, mesenchymal, clear cell and myxoid chondrosarcoma each. In the immunochemistry staining overexpression (>10% of cells) of CD44s was shown in 56.7% (17 of 30), of CD44v5 in 43.3% (13 of 30) and of CD44v6 in 6.7% (two of 30) of the tumors. Four grade III chondrosarcomas (80%) and 10 (71.4%) grade II chondrosarcomas showed overexpression for CD44s, whereas CD44s was overexpressed in only three (27.3%) grade I chondrosarcomas. Cox regression suggests overexpression of CD44s to be an additional prognostic marker for chondroid bone tumors independent of grading and other covariates.

CONCLUSIONS

Overexpression of CD44s correlated significantly with metastatic potential and with poorer survival in patients with chondrosarcoma. CD44s might be an independent additional marker, but small sample size remains to be considered.

Comethylation of p16 and MGMT genes in colorectal carcinoma: Correlation with clinicopathological features and prognostic value

AIM: To investigate the significance of p16 and O⁶-methylguanine-DNA methyltransferase (MGMT) genes promoter hypermethylation and K-ras mutations on colorectal tumorigenesis and progression.

METHODS: p16 and MGMT methylation status was examined on 47 tumor samples, and K-ras mutational status was examined on 85 tumor samples. For methylation analysis, a methylation specific PCR (MS-PCR) method was used.

RESULTS: p16 and MGMT promoter methylation was found in 51% (24/47) and 43% (20/47) of CRCs, respectively, and the K-ras mutation was found in 44% (37/85) of CRCs. Comethylation of p16 and MGMT genes was significantly associated with lower aggressiveness of the disease within a two-year period of observation. Only 27% of patients with simultaneous p16 and MGMT methylation showed the detectible occurrence of metastasis and/or death, compared to 67% of patients without double methylation or with no methylation (3/11 vs 22/33, P < 0.05, χ²-test). In addition, p16 and MGMT comethylation showed a trend toward an association with longer survival in patients with CRCs (35.5 ± 6.0 mo vs 23.1 ± 3.2 mo, P = 0.072, Log-rank test). Progression of the disease within a two-year period was observed in 66% of patients carrying the K-ras mutation, compared to only 19% of patients with wild type K-ras (29/44 vs 7/37, P < 0.001, χ²-test). The presence of the K-ras mutation significantly correlated to shortened overall survival (20.0 ± 1.9 mo vs 37.0 ± 1.8 mo, P < 0.001, Log-rank test). The comethylation of p16 and MGMT genes was significantly associated with lower aggressiveness of the disease even when K-ras mutations were included in the analysis as an independent variable.

CONCLUSION: Our data suggest that comethylation of promoters of p16 and MGMT genes could have a prognostic value in patients with CRC. Specifically, concurrent methylation of both genes correlates with better prognosis.

Proliferating endothelial cells and leukocyte infiltration as prognostic markers in colorectal cancer

BACKGROUND & AIMS

Leukocyte infiltration in tumors is dependent on angiogenic potential. In this study we aimed to retrospectively investigate the angiogenic potential in archival colorectal cancer (CRC) tissues and its relationship to amount and composition of the inflammatory infiltrate.

METHODS

In tumor tissues of 117 CRC patients with a 12-year follow-up, microvessel density (MVD) and proliferating endothelial cells (ECs) were assessed by CD31/CD34 double staining with the proliferation marker Ki-67. Leukocyte infiltration was determined by using CD45, CD3, CD8, CD16, CD20, and CD68 antibodies in peritumoral, tumor stroma, and intratumoral areas.

RESULTS

Proliferating ECs, but not MVD, are correlated to Dukes' stage and survival in CRC (P < .05). This parameter correlated significantly with the expression of vascular endothelial growth factor (r = 0.82; P < .012). The number of inflammatory cells in the tumor stroma and cells infiltrated into the tumor cell nests, but not of peritumoral leukocytes, predicted patient survival. This was most obvious for T lymphocytes (CD3; P < .05) and polymorphonuclear cells (CD16; P < .04). We found a significant relationship between angiogenesis parameters and infiltrated leukocytes (r = -0.70; P < .02). Combination of high numbers of infiltrated leukocytes and low amounts of proliferating ECs demonstrated to be an improved prognostic value compared with either parameter alone (P < .006).

CONCLUSIONS

We found a correlation between the intrinsic tumor parameters of ongoing angiogenesis and leukocyte infiltration with prognosis and survival in CRC. These findings have a potential impact on therapeutic applications for both antiangiogenesis as well as immunotherapy.

Phase I and pharmacokinetic evaluation of intravenous hyaluronic acid in combination with doxorubicin or 5-fluorouracil

BACKGROUND

Pre-clinically, hyaluronan (HA) has been demonstrated to systemically target chemotherapeutic drugs to tumours while ameliorating treatment toxicities. This study is a preliminary clinical investigation to determine if HA could be safely used in combination with 5-fluorouracil (5-FU) and doxorubicin (DOX).

METHODS

Thirty patients with metastatic cancer were intravenously administered 500 mg/m2 HA in combination with escalating doses of DOX (30-60 mg/m2) or 5-FU (cumulative dose of 1,350-2,250 mg/m2 per cycle). The effect of pre-administration of 20 mg/m2 of folinic acid on HA/5-FU chemotherapy was also investigated. Patients were randomized to receive either HA/chemotherapy or chemotherapy alone in their first treatment cycle and vice versa for the second cycle. Patients received HA and chemotherapy in all subsequent cycles.

RESULTS

Treatment was well tolerated, tumour responses were observed and the co-administration of HA did not alter the pharmacokinetics of clinically relevant doses of 5-FU or DOX.

CONCLUSION

High doses of intravenous high-molecular-weight HA can be safely co-administered with clinical doses of chemotherapy without significantly altering the toxicity or pharmacokinetics of the drugs or HA.

CD44s expression in resectable colorectal carcinomas and surrounding mucosa

BACKGROUND

CD44s (standard isoform) is a cell adhesion molecule belonging to the family of the hyaluronan-binding proteins. The CD44 family has been found to be overexpressed in epithelial tumors, where they are generally in relationship with tumor growth and metastasic properties. The aim of this work was to evaluate the membranous CD44s content in colorectal cancer and in healthy surrounding mucosa, its possible relationship with clinicopathological parameters, and its potential prognostic significance.

MATERIALS AND METHODS

Membranous CD44s levels were measured by an immunoenzymatic assay in tumors and surrounding mucosa samples from 72 patients with resectable colorectal carcinomas. The patients were followed for a mean time period of 30 months.

RESULTS

There was a wide variability of CD44s levels in tumor-surrounding mucosal samples (26.6-727 ng/mg protein) as well as in tumors (28.5-381 ng/mg protein). Tumor samples showed significantly higher CD44s levels (median: 99.1 ng/mg protein) than surrounding mucosal samples (81 ng/mg protein) (p=0.03). In the same way, CD44s levels in tumors as well as in surrounding mucosal samples were significantly higher in high S-phase tumors than in low S-phase tumors (p=0.001 for both). There was no significant relationship between tumor CD44s levels and patient's outcome. However, high levels of the glycoprotein in nonneoplastic surrounding mucosa were significantly (p=0.018) associated with a poor overall patient survival.

CONCLUSION

CD44s may play a role in the tumorogenesis of colorectal carcinomas. In addition, CD44s levels in tumor-surrounding mucosa may provide, in concert with some clinicopathological parameters, important information about prognostic evaluation of patients with resectable colorectal carcinomas.

Expression and clinical significance of CD44V5 and CD44V6 in resectable colorectal cancer

PURPOSE

This study was conducted to evaluate the prognostic significance of CD44v5 and CD44v6 in resectable colorectal cancer.

MATERIALS AND METHODS

Membranous CD44v5 and CD44v6 levels were measured by an immunoenzymatic assay in tumors and surrounding mucosal samples obtained from 105 patients with resectable colorectal carcinomas.

RESULTS

There were no significant differences of CD44v5 levels between tumors [median: 3.2 (range: 0.9-83.5) ng/mg protein) and surrounding mucosal samples (3 (3-146.2) ng/mg protein]. However, tumor samples showed significantly higher CD44v6 levels [19.5 (2.2-562.9) ng/mg protein] than mucosal samples [5 (5-230) ng/mg protein] (P=0.0001). Patients with higher CD44v5 or CD44v6 content in tumor samples had a considerably shorter relapse-free survival (P<0.05, for both). Patients with a higher CD44v6 content also had a shorter relapse-free and overall survival in the multivariate analysis (P<0.05).

CONCLUSION

The results of this study suggest a role of CD44v5 and CD44v6 in colorectal cancer progression. Membranous CD44v levels in primary tumors, measured by immunoenzymatic assay, may contribute to a more precise prognostic estimation in patients with resectable colorectal cancer.

Prognostic significance of biomarkers in squamous cell carcinoma of the tongue: multivariate analysis

BACKGROUND AND OBJECTIVES

Expression of a panel of biomarkers, such as p53, Bcl-2, Cyclin D1, c-myc, p21ras, c-erb B2, cytokeratin-19 (CK-19), and factor VIII-related antigen (FVIII-RA), was studied together in anterior tongue tumors from the oral cavity and in posterior tongue tumors from the oropharynx of patients with early- and locally advanced-stage disease, to evaluate their prognostic value.

METHODS

The expression of the above-mentioned biomarkers was studied by immunohistochemical localization.

RESULTS

In this study, 18%, 26%, 62%, 75%, 73%, 50%, and 29% of the tumors exhibited p53, Bcl-2, Cyclin D1, c-myc, p21ras, c-erb B2, and CK-19 expression, respectively. Twenty percent of the tumors had a microvessel count of >0.0. The expression of these biomarkers was also correlated with clinicopathologic parameters. In early-stage patients with a tobacco habit, who showed borderline significance for relapse-free survival by Kaplan-Meier survival analysis, this turned out to be significant, with the general linear model univariate survival analysis. In the total group, disease stage emerged as the most significant prognostic factor, followed by c-myc, when Cox forward stepwise regression and general linear model multivariate survival analysis were performed. However, Cyclin D1, which was significant by Cox forward stepwise regression analysis, lost its significance by general linear model multivariate analysis. In patients with early-stage disease, MVC, which was a significant predictor of disease relapse by Cox forward stepwise regression analysis, lost its significance by general linear model analysis because of small number of patients. In patients with locally advanced tongue cancer, multivariate survival analysis of individual biomarkers by both Cox forward stepwise regression and general linear model analysis indicated c-myc expression to be strongly indicative of poor prognosis. However, multivariate analysis of individual markers along with a combination of markers showed that only by Cox forward stepwise regression analysis did the combined expression of markers c-myc, Cyclin D1, and p21ras emerge as a significant independent prognosticator.

CONCLUSIONS

Overall stage emerged as the most significant prognostic indicator of disease outcome. Tobacco habit also affected relapse-free survival in patients with early-stage disease. However, immunostaining of c-myc in the tumors of locally advanced-stage tongue cancer patients might be a potential adjunct to clinical stage in the pathologic evaluation of tongue specimens.

Morphologic analysis of microvessels in colorectal tumors with respect to the formation of liver metastases

BACKGROUND AND OBJECTIVES

Overexpression of VEGF and proliferation of microvessels are strongly related to liver metastases, however, morphologic analyses of microvessels in liver metastases have not been reported. The purpose of the present study was to examine the correlation between liver metastases and the diameters of microvessel lumens in the tumor tissue.

METHODS

Fifty-nine patients with liver metastases from colorectal cancers and 112 patients who underwent curative colorectal resection and survived without any recurrence were reviewed. Microvessel density (MVD) and the diameters of the lumens of individual microvessels were assessed.

RESULTS

There was a significant difference in terms of the mean MVD of primary tumors between patients with liver metastases and those without liver metastases. The numbers of patients with liver metastases who had microvessels 100-200 microm in diameter and microvessels more than 200 microm in diameter were significantly greater than patients without liver metastases. Microvessels with lumens more than 100 microm in diameter were not detected in the liver metastatic lesion.

CONCLUSION

Large microvessels in the primary tumor favor intravasation of cancer cells.

Molecular markers are predictors of recurrence and survival in patients with Dukes B and Dukes C colorectal adenocarcinoma

PURPOSE

The goal was to investigate the prognostic value of various molecular markers like CEA, Cyclin D1, Bcl-2, c-Myc, p53, p21ras, Ki-67, CD44, Factor VIII-related antigen, cytokeratin-19, adenoma antigen, and prolactin in patients with Dukes B and Dukes C colorectal adenocarcinoma.

METHODS

These molecular markers were localized immunohistochemically in nonmalignant (n = 36) and malignant (n = 98) diseases of the colorectum. Data were analyzed statistically using the SPSS software program. The patients with colorectal cancer were followed for a period of five years or their death within that period.

RESULTS

The expression of carcinoembryonic antigen, Cyclin D1, Bcl-2, CD44, cytokeratin-19 and prolactin was significantly higher in malignant diseases (P < 0.05), whereas, p21ras was found to be significantly higher in nonmalignant diseases (P = 0.002) as compared with their respective counterparts. Besides Dukes stage, multivariate analysis indicated a significantly reduced relapse-free survival in patients expressing CD44 and cytokeratin-19 (P < 0.005). Similarly, besides Dukes stage, multivariate analysis indicated a significantly poor overall survival in patients expressing CD44, cytokeratin-19 and prolactin (P < 0.01). In patients with Dukes B disease, only cytokeratin-19 and CD44 expression attained statistical significance (P < 0.05), whereas in patients with Dukes C disease, CD44, p21ras- and c-Myc expression attained statistical significance (P < 0.018). Also, a multivariate analysis in relation to treatment given was performed using CD44 and cytokeratin-19.

CONCLUSION

Besides Dukes stage, multivariate analysis of all the studied molecular markers showed that patients expressing CD44 and cytokeratin-19 had a significantly reduced relapse-free and poor overall survival. Moreover, patients expressing both these markers (CD44 and cytokeratin-19) had the lowest significant relative risk for developing recurrence than patients with both markers negative when treated with surgery followed by adjuvant chemotherapy as compared with patients treated with surgery alone. Thus, in patients with colorectal cancer, immunohistochemical localization of CD44 and cytokeratin-19 may be included as a part of routine pathologic evaluation along with conventional prognostic factors.

Expression of c-Met and heparan-sulfate proteoglycan forms of CD44 in colorectal cancer

In colorectal cancer patients, prognosis is not determined by the primary tumor but by the formation of distant metastases. Molecules that have been implicated in the metastatic process are the proto-oncogene product c-Met and CD44 glycoproteins. Recently, we obtained evidence for functional collaboration between these two molecules: CD44 isoforms decorated with heparan sulfate chains (CD44-HS) can bind the c-Met ligand, the growth and motility factor hepatocyte growth factor/scatter factor (HGF/SF). This interaction strongly promotes signaling through the receptor tyrosine kinase c-Met. In the present study, we explored the expression of CD44-HS, c-Met, and HGF/SF in the normal human colon mucosa, and in colorectal adenomas and carcinomas, as well as their interaction in colorectal cancer cell lines. Compared to the normal colon, CD44v3 isoforms, which contain a site for HS attachment, and c-Met, were both overexpressed on the neoplastic epithelium of colorectal adenomas and on most carcinomas. Likewise, HGF/SF was expressed at increased levels in tumor tissue. On all tested colorectal cancer cell lines CD44v3 and c-Met were co-expressed. As was shown by immunoprecipitation and Western blotting, CD44 on these cells lines was decorated with HS. Interaction with HS moieties on colorectal carcinoma (HT29) cells promoted HGF/SF-induced activation of c-Met and of the Ras-MAP kinase pathway. Interestingly, survival analysis showed that CD44-HS expression predicts unfavorable prognosis in patients with invasive colorectal carcinomas. Taken together, our findings indicate that CD44-HS, c-Met, and HGF/SF are simultaneously overexpressed in colorectal cancer and that HS moieties promote c-Met signaling in colon carcinoma cells. These observations suggest that collaboration between CD44-HS and the c-Met signaling pathway may play an important role in colorectal tumorigenesis.

Prognostic significance of immunohistochemically localized biomarkers in stage II and stage III breast cancer: a multivariate analysis

BACKGROUND

The aim was to investigate the expression of a panel of biomarkers such as prolactin (PRL), p53, Bcl-2, c-erb B2, Ki-67, CD44, and factor VIII-related antigen (FVIII-RA) in primary tumors of stage II and stage III breast cancer and its correlation with disease prognostication.

METHODS

The streptavidin-biotin peroxidase complex technique was used for the detection of these antigens. Cytoplasmic staining pattern was observed for PRL, Bcl-2, and Ki-67. Staining pattern for p53 was nuclear. Membranous and/or cytoplasmic staining was noted for c-erb B2 and CD44. Microvessel staining was noted for FVIII-RA.

RESULTS

Of the 93 primary breast tumors analyzed, positivity for PRL was noted in 82%, for p53 in 56%, for Bcl-2 in 73%, for c-erb B2 in 68%, and for Ki-67 and CD44 in 78% each. The microvessel count (MVC) for FVIII-RA ranged from 0.0 to 29.0, with a median of 6.0, which was used as a cutoff. MVC > or = 6.0 was noted in 51% of breast tumors. With increasing tumor size, the higher frequency of positivity of MVC > or = 6.0 (P = .0001), CD44 (P = .001), PRL (P = .002), and c-erb B2 (P = .008), and higher frequency of Bcl-2 negativity (P = .033), was noted. In stage III patients, a higher positivity of the following biomarkers was noted, compared with stage II patients: MVC > or = 6.0 (P = .0004), PRL (P = .0002), c-erb B2 (P = .001), and CD44 (P = .005). Further, Bcl-2 positivity was significantly lower in patients with stage III disease compared with those with stage II disease (P = .024). In patients with nodal involvement, the frequency of c-erb B2 (P = .006), MVC > or = 6.0 (P = .011), and PRL (P = .032) was higher than in those without nodal involvement. Moreover, in these patients, with the increase in the number of involved lymph nodes, there was a significant increase in frequency of CD44+ (P = .0004) and PRL+ (P = .013) tumors. Abnormal expression of one biomarker was seen in 7% of tumors, of two biomarkers in 4%, of three in 15%, of four in 19%, of five in 28%, of six in 20%, and of all seven biomarkers in 7% of tumors. The frequency of an increasing number of biomarkers coexpressed was higher in stage III patients compared with stage II patients (P = .00003). In the total number of patients (n = 93), tumors with Bcl-2 negativity (P = .00001), MVC > or = 6.0 (P = .001), PRL positivity (P = .02), and CD44 positivity (P = .034) had a significantly poorer overall survival (OS) compared with their respective counterparts. In stage II patients (n = 40), only p53 expression was significantly associated with reduced relapse-free survival (P = .009) and OS (P = .040). In multivariate analysis, p53 expression was an independent prognostic factor that influenced relapse-free survival (P = .034) of stage II breast cancer patients. However, it failed to attain statistical significance for OS. In stage III patients (n = 53), tumors with Bcl-2 negativity (P = .0005) and MVC > or = 6.0 (P = .039) had a significantly poorer OS compared with their respective counterparts. In multivariate analysis of stage III patients, Bcl-2 was the only independent prognostic factor (P = .001) for predicting OS. There was a significant association between coexpression of the biomarkers and OS (P = .001). The OS rates decreased with the increase in number of abnormally expressed biomarkers.

CONCLUSIONS

p53 expression in primary tumors was an independent prognostic factor that influenced relapse-free survival in patients with stage II disease. In stage III patients, lack of Bcl-2 expression was independently associated with a poor prognosis and, thus, may be an indicator of aggressive phenotype.