Reduced expression of CD44 v3 and v6 is related to invasion in lung adenocarcinoma

Stromal micropapillary pattern and CD44s expression predict worse outcome in lung adenocarcinomas with micropapillary pattern

OBJECTIVES

This study aims to investigate the clinicopathologic characteristics of lung adenocarcinoma with micropapillary pattern (MPP) and the expression of CD44s and CD44v6 in MPP.

METHODS

A total of 202 patients diagnosed with primary lung adenocarcinoma with MPP were included. We estimated the proportion of MPP in each tumor tissue and divided MPP into aerogenous micropapillary pattern (AMP) and stromal micropapillary pattern (SMP). The expression of CD44s and CD44v6 was estimated by immunohistochemical staining. Clinicopathologic data were collected from the patients' medical records. We also collected patients' follow-up data and used PFS (progression-free survival) as a survival indicator.

RESULTS

Lung adenocarcinoma with MPP had a high risk of pleural invasion, lymph node metastasis, in advanced TNM stage, and a high rate of EGFR mutation. The presence of SMP indicated a higher rate of pleural invasion, lymphovascular invasion, lymph node metastasis, and a worse PFS compared with pure AMP. We found high expression of CD44s in micropapillary, especially in AMP, while the absence of CD44s expression indicated shorter survival, which was an independent unfavorable factor for PFS.

CONCLUSIONS

Lung adenocarcinoma with micropapillary pattern indicated an unfavorable prognosis, which had two different pattens, AMP and SMP. SMP indicated a worse survival than AMP, and was an independent unfavorable factor for PFS. So, AMP/SMP subclassification is necessary to evaluate patient's prognosis. Furthermore, the absent expression of CD44s in micropapillary indicated shorter survival, especially in patients with EGFR mutation. Herein, CD44s may be a biological marker for micropapillary lung adenocarcinoma.

Novel CD44-downstream signaling pathways mediating breast tumor invasion

CD44, also known as homing cell adhesion molecule is a multi-structural cell molecule involved in cell-cell and cell-extracellular matrix communications. CD44 regulates a number of central signaling pathways, including PI3K/AKT, Rho GTPases and the Ras-MAPK pathways, but also acts as a growth/arrest sensor, and inhibitor of angiogenesis and invasion, in response to signals from the microenvironment. The function of CD44 has been very controversial since it acts as both, a suppressor and a promoter of tumor growth and progression. To address this discrepancy, we have previously established CD44-inducible system both in vitro and in vivo. Next, using microarray analysis, we have identified and validated Survivin, Cortactin and TGF-β2 as novel CD44-downstream target genes, and characterized their signaling pathways underpinning CD44-promoted breast cancer (BC) cell invasion. This report aims to update the literature by adding and discussing the impact of these novel three signaling pathways to better understand the CD44-signaling pathways involved in BC tumor cell invasion.

A self-enforcing CD44s/ZEB1 feedback loop maintains EMT and stemness properties in cancer cells

Invasion and metastasis of carcinomas are often activated by induction of aberrant epithelial-mesenchymal transition (EMT). This is mainly driven by the transcription factor ZEB1, promoting tumor-initiating capacity correlated with increased expression of the putative stem cell marker CD44. However, the direct link between ZEB1, CD44 and tumourigenesis is still enigmatic. Remarkably, EMT-induced repression of ESRP1 controls alternative splicing of CD44, causing a shift in the expression from the variant CD44v to the standard CD44s isoform. We analyzed whether CD44 and ZEB1 regulate each other and show that ZEB1 controls CD44s splicing by repression of ESRP1 in breast and pancreatic cancer. Intriguingly, CD44s itself activates the expression of ZEB1, resulting in a self-sustaining ZEB1 and CD44s expression. Activation of this novel CD44s-ZEB1 regulatory loop has functional impact on tumor cells, as evident by increased tumor-sphere initiation capacity, drug-resistance and tumor recurrence. In summary, we identified a self-enforcing feedback loop that employs CD44s to activate ZEB1 expression. This renders tumor cell stemness independent of external stimuli, as ZEB1 downregulates ESRP1, further promoting CD44s isoform synthesis.

Demonstration of a melanoma-specific CD44 alternative splicing pattern that remains qualitatively stable, but shows quantitative changes during tumour progression

The role of CD44 in the progression of human melanoma has mostly been characterised by qualitative changes in expression of its individual variable exons. These exons however, may be expressed to form a number of molecules, the alternative splice variants of CD44, which may be structurally and functionally different. Using real-time PCR measurements with variable exon specific primers we have determined that all are expressed in human melanoma. To permit comparison between different tumours we identified a stable CD44 variable exon (CD44v) expression pattern, or CD44 ‘fingerprint’. This was found to remain unchanged in melanoma cell lines cultured in different matrix environments. To evaluate evolution of this fingerprint during tumour progression we established a scid mouse model, in which the pure expression pattern of metastatic primary tumours, circulating cells and metastases, non-metastatic primary tumours and lung colonies could be studied. Our analyses demonstrated, that although the melanoma CD44 fingerprint is qualitatively stable, quantitative changes are observed suggesting a possible role in tumour progression.

DcR3 binds to ovarian cancer via heparan sulfate proteoglycans and modulates tumor cells response to platinum with corresponding alteration in the expression of BRCA1

BACKGROUND

Overcoming platinum resistance is a major obstacle in the treatment of Epithelial Ovarian Cancer (EOC). In our previous work Decoy Receptor 3 (DcR3) was found to be related to platinum resistance. The major objective of this work was to define the cellular interaction of DcR3 with EOC and to explore its effects on platinum responsiveness.

METHODS

We studied cell lines and primary cultures for the expression of and the cells ability to bind DcR3. Cells were cultured with DcR3 and then exposed to platinum. Cell viability was determined by MTT assay. Finally, the cells molecular response to DcR3 was studied using real time RT-PCR based differential expression arrays, standard RT-PCR, and Western blot.

RESULTS

High DcR3 in the peritoneal cavity of women with EOC is associated with significantly shorter time to first recurrence after platinum based therapy (p = 0.02). None-malignant cells contribute DcR3 in the peritoneal cavity. The cell lines studied do not secrete DcR3; however they all bind exogenous DcR3 to their surface implying that they can be effected by DcR3 from other sources. DcR3s protein binding partners are minimally expressed or negative, however, all cells expressed the DcR3 binding Heparan Sulfate Proteoglycans (HSPGs) Syndecans-2, and CD44v3. DcR3 binding was inhibited by heparin and heparinase. After DcR3 exposure both SKOV-3 and OVCAR-3 became more resistant to platinum with 15% more cells surviving at high doses. On the contrary CaOV3 became more sensitive to platinum with 20-25% more cell death. PCR array analysis showed increase expression of BRCA1 mRNA in SKOV-3 and OVCAR-3 and decreased BRCA1 expression in CaOV-3 after exposure to DcR3. This was confirmed by gene specific real time PCR and Western blot analysis.

CONCLUSIONS

Non-malignant cells contribute to the high levels of DcR3 in ovarian cancer. DcR3 binds readily to EOC cells via HSPGs and alter their responsiveness to platinum chemotherapy. The paradoxical responses seen were related to the expression pattern of HSPGs available on the cells surface to interact with. Although the mechanism behind this is not completely known alterations in DNA repair pathways including the expression of BRCA1 appear to be involved.

Expression of CD44s and CD44v6 in lung cancer and their correlation with prognostic factors

BACKGROUND

CD44, a transmembrane glycoprotein receptor, plays a major role in tumor progression and metastasis.

OBJECTIVE

To evaluate the expression of CD44 standard (CD44s) and its variant 6 (CD44v6) in normal and neoplastic lung tissue and correlate it with prognostic factors in lung cancer.

METHODS

The study included 52 non-small cell lung carcinomas (NSCLC) (21 squamous cell carcinomas and 31 adenocarcinomas), 15 small cell lung carcinomas (SCLC) and 8 carcinoid tumors. Expression of CD44s and CD44v6 was evaluated by immunohistochemistry and correlated with lung cancer prognostic factors.

RESULTS

All squamous cell carcinomas expressed both CD44s and CD44v6. Adenocarcinomas expressed CD44s in 39% of cases and CD44v6 in 45%. Carcinoid tumors expressed only CD44s in 88% of cases. All SCLCs were negative for both CD44s and CD44v6. A restricted panel consisting of CD44s and CD44v6 will discriminate NSCLC from SCLC with a sensitivity of 67% and a specificity of 100%. In adenocarcinoma CD44s expression was significantly correlated with lymph node metastases (p=0.007) while CD44v6 expression was more significantly associated with tumor size (p=0.0032).

CONCLUSIONS

CD44s and CD44v6 are expressed in certain types of lung cancer. In adenocarcinoma CD44s and CD44v6 expression is significantly correlated with lymph node metastases and tumor size.

Aerosol delivery of small hairpin osteopontin blocks pulmonary metastasis of breast cancer in mice

Background

Metastasis to the lung may be the final step in the breast cancer-related morbidity. Conventional therapies such as chemotherapy and surgery are somewhat successful, however, metastasis-related breast cancer morbidity remains high. Thus, a novel approach to prevent breast tumor metastasis is needed.

Methodology/Principal Finding

Aerosol of lentivirus-based small hairpin osteopontin was delivered into mice with breast cancer twice a week for 1 or 2 months using a nose-only inhalation system. The effects of small hairpin osteopontin on breast cancer metastasis to the lung were evaluated using near infrared imaging as well as diverse molecular techniques. Aerosol-delivered small hairpin osteopontin significantly decreased the expression level of osteopontin and altered the expression of several important metastasis-related proteins in our murine breast cancer model.

Conclusion/Significance

Aerosol-delivered small hairpin osteopontin blocked breast cancer metastasis. Our results showed that noninvasive targeting of pulmonary osteopontin or other specific genes responsible for cancer metastasis could be used as an effective therapeutic regimen for the treatment of metastatic epithelial tumors.

Expression and prognostic relevance of CD44v6 in stage I non-small cell lung carcinoma

PURPOSE

Expression of CD44 and its variants has been shown to be relevant to tumor progression in various human malignancies. We evaluated the expression of CD44v6 in the primary lesions of stage I non-small cell lung cancer (NSCLC) and correlated the expression level to its prognosis.

METHODS

The expression of CD44v6, measured by immunohistochemistry, was assessed in the tumor specimens from 190 patients with stage I NSCLC. Each slide was assigned a score: the average of the score of tumor cells staining multiplied by the score of staining intensity. And depending on the cut-off score based on receiver operating characteristic (ROC) curve analysis, the CD44v6 expression was categorized into high- and low-level groups, which were then correlated directly with the clinical outcomes.

RESULTS

The high expression of CD44v6 was detected more frequently in the squamous cell carcinoma (38 of 71 patients, 53.5%) than in the other types of carcinoma (p < 0.05). The Kaplan-Meier survival curves showed that high level expression of CD44v6 indicated a better post-operative survival (p = 0.006), especially for stage IB disease (p = 0.049) and squamous cell carcinoma (p = 0.029). The multivariate analysis also confirmed that the expression of CD44v6 was an independent prognostic indicator (p = 0.011).

CONCLUSIONS

CD44v6 might be correlated with histogenesis of NSCLC, and its decreased expression may be an adverse prognostic indicator for the patients with stage I NSCLC, especially for those with stage IB diseases. Patients of this subgroup might need adjuvant therapy additionally.

CD44v3 levels in primary cutaneous melanoma are predictive of prognosis: Assessment by the use of tissue microarray

Despite the use of sentinel node biopsy techniques, the search continues for other strategies to improve the accuracy of estimating prognosis in melanoma patients. Various biomarkers have previously been studied for use in this role, but none has yet achieved acceptance in routine practice. We have applied the novel technology of tissue microarray for the high throughput screening of a cohort of 120 primary cutaneous melanoma specimens for expression of the transmembrane glycoprotein CD44, splice variant 3 (v3), which has previously been implicated in tumor progression. A highly significant correlation between CD44v3 expression and Breslow thickness, Clark's level and patient age was demonstrated (Spearman correlation p < 0.001). Regarding clinical outcome, CD44v3 expression was shown to be significantly associated with better outcome (chi(2) = 7.2219, p = 0.0072). Furthermore, subgroup analysis revealed a sequentially improved survival probability associated with the intensity of CD44v3 staining (chi(2) = 12.5162, p = 0.0058). Analysis in a Cox multivariate model, however, did not show CD44v3 to be independently predictive of prognosis. The implications of these findings are considered, and the use of CD44v3 as a potential prognostic marker or a target for therapeutic manipulation are discussed.

The prognostic value of adhesion molecule CD44v6 in women with primary breast carcinoma: a clinicopathologic study

AIMS

CD44 functions as an adhesion molecule. Within the family of CD44 isoforms, the spliced variant 6 has been causally associated with the development of metastases and poor prognosis in animal models and several human cancers. The aim of this study was to investigate the prognostic value of CD44v6 in women with primary breast carcinoma.

MATERIALS AND METHODS

The women with primary breast carcinoma in this study were followed up clinically for a period of 5 years. Clinicopathologic features, including tumour size, axillary nodal status, histological grade and pTNM stage, were determined for a cohort of 78 women presenting with primary breast carcinoma. Standard immunohistochemistry was used to explore CD44v6 expression. The data obtained were analysed by univariate and multivariate analyses.

RESULTS

Forty-three out of 78 (55%) women with breast carcinoma were CD44v6-positive (i.e. over 5% of tumour cells exhibited positive staining). Significant sequential increase of CD44v6 expression was observed in women with metastases of axillary nodes, tumour size more than 2 cm, advanced pTNM stage and survival period less than 5 years. Univariate analysis showed that axillary nodal status, primary tumour size, histological grade, and pTNM stage were associated with 5-year survival, and CD44v6 expression was associated with primary tumour size, axillary nodal status, pTNM stage and 5-year survival. In multivariate analysis, using the Cox-regression model, CD44v6 expression was not an independent prognostic factor.

CONCLUSIONS

CD44v6 expression was correlated with tumour size, metastases of axillary nodes, pTNM stage, and 5-year survival; however, multivariate analysis revealed that CD44v6 expression failed to be an independent predictor of patient prognosis.

Versican in nonsmall cell lung cancer: relation to hyaluronan, clinicopathologic factors, and prognosis

The aim of the study was to investigate the expression and prognostic role of versican in 212 patients with resected nonsmall cell lung cancer. Tumor samples were stained immunohistochemically, and the versican staining was evaluated both in tumor stroma and cancer cells. The staining results were compared to the clinical data of the patients, the tumor cell proliferation, and the expression of hyaluronan. In the whole material, low and high area percentages of stromal versican staining were observed in 135 and 77 carcinomas, respectively. Tumor cell-associated staining signal for versican was observed in 33 cases. In the whole material, the significant relationship between high stromal staining of versican and that of hyaluronan was noticed (P = .001). The expression of stromal versican was related to tumor type (P = .008) and high stromal staining was inversely correlated with poor tumor differentiation (P = .045), but not with tumor cell proliferation. Among adenocarcinomas, the high stromal staining of versican was associated with tumor recurrence (P = .024), higher tumor stage (P = .022), and lymph node metastases (P = .042). Versican expression was not related to patient outcome in the whole material, but among adenocarcinomas, the high stromal staining was related to poor disease-free survival (P = .0056). However, in Cox multivariate analysis with tumor stage, versican expression did not retain its prognostic significance. The results indicate that increased stromal versican is related to higher tumor recurrence rate and more advanced disease. Despite the important role of versican in nonsmall cell lung cancer, traditional clinicopathologic factors remained most significant in the current study.