Low Mast Cell Density Predicts Poor Prognosis in Oral Squamous Cell Carcinoma and Reduces Survival in Head and Neck Squamous Cell Carcinoma.

BACKGROUND: The cellular composition of the tumor microenvironment (TME) at the invading front of oral squamous cell carcinomas (OSCCs) may reflect biologically important cancer features and host responses, and thus be related to disease progression. The TME density of mast cells (MCs), macrophages, cancer-associated fibroblasts (CAFs) and endothelial cells were quantified at the invasive front and analyzed regarding their relation to disease recurrence in patients with small T1/2N0M0 OSCCs. mRNA for MC-specific proteins were analyzed in a second patient cohort with head and neck squamous cell carcinoma (HNSCC). MATERIALS AND METHODS: Samples from 62 patients with T1/2N0M0 OSCC were immunohistochemically stained and scored for the cellular expression of mast/stem cell growth factor receptor (c-KIT) (MCs), CD68 (macrophages), α-smooth muscle actin (α-SMA) (CAFs) and CD31 (endothelial cells) and this was analyzed according to disease recurrence. Data from The Cancer Genome Atlas database were used to examine mRNA expression profiles and clinical data of patients with 399 HNSCC. RESULTS: Increased MC density at the invasive front was significantly associated with reduced disease recurrence, as none of the patients with high MC density experienced relapse. Moreover, increased expression of mRNA for MC specific markers as c-KIT, and α-, ß-, and δ-tryptases and the MC-stimulating factor, stem cell factor (SCF), was significantly associated with good prognosis in patients with HNSCC. CONCLUSION: Decreased MC density at the invasive front may reflect tumor biology related to disease progression and prognosis. Counting MCs seems to be an easy and practical tool, that could be utilized for prognostic evaluation.

Tumor Budding, EMT and Cancer Stem Cells in T1-2/N0 Oral Squamous Cell Carcinomas.

BACKGROUND: Early oral carcinomas have a high recurrence rate despite surgery with clear margins. In an attempt to classify the risk of recurrence of oral squamous cell carcinomas, we explored the significance of tumor budding, epithelial-mesenchymal transition (EMT) and certain cancer stem cell markers (CSC). MATERIALS AND METHODS: Tumor budding (single cells or clusters of ≤5 cells in the tumor front, divided into high- and low-budding tumors), EMT and CSC markers were studied in 62 immunohistochemically stained slides of T1/2N0M0 oral squamous cell carcinomas. Tissues and records of follow-up were obtained from the Oslo University Hospital, Norway. Tumor budding, EMT and CSC markers were scored and analyzed. RESULTS: The only significant prognostic marker was tumor budding (p=0.043). Expression of the EMT marker E-cadherin was lost from the invasive front and tended to be a prognostic factor (p=0.17), and up-regulation of vimentin in tumor cells in the invasive front was found; this indicates that EMT had occurred. CSC markers were not associated with recurrence rate in the present study. CONCLUSION: A high budding index was related to poor prognosis in patients with oral cancer. Budding was associated with EMT-like changes. CSC factors were detected but reflected differentiation rather than stemness. Scoring of buds in patients with oral cancer may help discriminate invasive tumors prone to relapse, and thus, provide an indication for adjuvant therapy.

High nuclear SOX2 expression is associated with radiotherapy response in small (T1/T2) oral squamous cell carcinoma.

OBJECTIVE: Expression of the stem cell transcription factor SOX2 is often used to imply stemness and poor prognosis in cancer. However, its role in oral squamous cell carcinoma (OSCC) is not fully elucidated. MATERIAL AND METHODS: Tumour tissues from 62 patients with primary, node negative and non-metastatic OSCCs were used to evaluate SOX2 expression by immunohistochemistry. The results were correlated to clinicopathology, treatment and disease recurrences. RESULTS: The majority of the OSCCs (88%) expressed SOX2. Patients with higher nuclear SOX2 staining intensity in the invasive front compared to the adjacent normal epithelium, had a remarkable longer disease-free period if they received adjuvant post-operative radiotherapy (P = 0.001). This was in particular evident for highly differentiated OSCCs, as none of the high SOX2-expressing tumours reoccurred in contrast to all low SOX2-expressing OSCCs. CONCLUSIONS: High nuclear SOX2 expression in the invasive front was associated with dramatic longer disease-free period than low SOX2-expressing carcinomas after post-operative radiotherapy in small OSCCs. The result suggested that high nuclear SOX2 expression at the invasive front may predict radiosensitivity.

An investigation into anti-proliferative effects of microRNAs encoded by the miR-106a-363 cluster on human carcinoma cells and keratinocytes using microarray profiling of miRNA transcriptomes.

Transfection of human oral squamous carcinoma cells (clone E10) with mimics for unexpressed miR-20b or miR-363-5p, encoded by the miR-106a-363 cluster (miR-20b, miR-106a, miR-363-3p, or miR-363-5p), caused 40-50% decrease in proliferation. Transfection with mimics for miR-18a or miR-92a, encoded by the miR-17-92 cluster (all members being expressed in E10 cells), had no effect on proliferation. In contrast, mimic for the sibling miRNA-19a yielded about 20% inhibition of proliferation. To investigate miRNA involvement profiling of miRNA transcriptomes were carried out using deoxyoligonucleotide microarrays. In transfectants for miR-19a, or miR-20b or miR-363-5p most differentially expressed miRNAs exhibited decreased expression, including some miRNAs encoded in paralogous miR-17-92-or miR-106b-25 cluster. Only in cells transfected with miR-19a mimic significantly increased expression of miR-20b observed-about 50-fold as judged by qRT-PCR. Further studies using qRT-PCR showed that transfection of E10 cells with mimic for miRNAs encoded by miR-17-92 - or miR-106a-363 - or the miR-106b-25 cluster confirmed selective effect on expression on sibling miRNAs. We conclude that high levels of miRNAs encoded by the miR-106a-363 cluster may contribute to inhibition of proliferation by decreasing expression of several sibling miRNAs encoded by miR-17-92 or by the miR-106b-25 cluster. The inhibition of proliferation observed in miR-19a-mimic transfectants is likely caused by the miR-19a-dependent increase in the levels of miR-20b and miR-106a. Bioinformatic analysis of differentially expressed miRNAs from miR-106a, miR-20b and miR-363-5p transfectants, but not miR-92a transfectants, yielded significant associations to "Cellular Growth and Proliferation" and "Cell Cycle." Western blotting results showed that levels of affected proteins to differ between transfectants, suggesting that different anti-proliferative mechanisms may operate in these transfectants.

Migration induced by epidermal and hepatocyte growth factors in oral squamous carcinoma cells in vitro: role of MEK/ERK, p38 and PI-3 kinase/Akt.

BACKGROUND: Cell migration is a necessary part of malignant invasiveness. Oral squamous cell carcinomas (OSCC) have a great tendency for local invasive growth. We have investigated signalling pathways involved in cell migration induced by epidermal growth factor (EGF) and hepatocyte growth factor (HGF) in OSCC cells and examined the effects of various experimental and clinically approved anti-tumour signal inhibitors on the migratory activity. METHODS: Migration was studied in three human OSCC cell lines, using a scratch wound assay in vitro and time-lapse cinematography. Specific phosphorylation of signalling proteins was assessed by Western blotting. RESULTS: In the E10 cell line, EGF and HGF induced phosphorylation of EGF receptor (EGFR) and Met, respectively, phosphorylation of ERK1/2, p38 and Akt, and dose-dependent activation of cell migration. Addition of the EGFR-specific inhibitors cetuximab (antibody) or gefitinib (tyrosine kinase blocker) abolished cell migration elicited by EGF. Similarly, a Met kinase inhibitor (SU11274) blocked HGF-induced cell migration. Furthermore, when three cell lines were treated with blockers of the MEK/ERK, p38 or the PI-3 kinase/Akt pathways, the migratory response to both EGF and HGF was inhibited, but to varying degrees. Notably, in E10 and D12 cells, HGF-induced migration was particularly sensitive to PI-3 K-inhibition, while in C12 cells, both HGF- and EGF-induced migration were highly sensitive to p38-blockade. CONCLUSION: The results demonstrate that the MEK/ERK, p38 and PI-3 kinase pathways are all involved in mediating the increased migration in OSCC cell lines induced by EGF and HGF, but their relative importance and the effects of specific signal inhibitors differ.

Expression of members of the miRNA17-92 cluster during development and in carcinogenesis.

The six microRNAs (miRNA) encoded by the miR-17-92 cluster, also named oncomir-1, have been associated with carcinogenesis and typically exhibit-increased expression in tumors. Despite the well-established role for the miR-17-92 cluster in an oncogenic network, the physiological function of these miRNAs in normal tissues remains unresolved. In order to investigate whether there are similar patterns of miR-17-92 expression during embryogenesis and carcinogenesis, we have preformed a systematic study of the expression in cultured carcinoma cells, cultured primary human keratinocytes (KC), and during development of some murine tissues. Both levels of expression of the primary transcript (pri-miRNA) and levels of expression of the individual members of the cluster were monitored. Irrespectively of tissue examined we found that the level of expression decreased markedly during development. With cultured primary human KCs their levels of expression of some of these microRNAs decreased as the number of cell passages increased. Their levels of expression in cultured carcinoma cells, in contrasts, increased, or remained unchanged, with increasing number of cell passages. The results suggest these microRNAs are involved in the regulation of foetal development and that they may promote proliferation and inhibit differentiation during embryogenesis and carcinogenesis. Additionally, the six microRNAs exhibit variable tissue expression, suggesting selective processing of these microRNAs.

Nuclear and cytoplasmic expression of Met in oral squamous cell carcinoma and in an organotypic oral cancer model.

Met, the hepatocyte growth factor receptor, is important in transducing signals for tumour growth and metastasis. The aim of this study was to examine the pattern of Met expression and its value as a prognostic factor in oral squamous cell carcinomas (OSCCs). The material consisted of 53 OSCCs and five healthy controls from normal oral mucosa supplied with cell lines, 10 organotypic models supplied with oral cancer cells, and three organotypic models supplied with normal keratinocytes. Met protein expression was assessed by immunohistochemistry and western blotting. Met expression was scarce and limited to the basal layer in normal oral mucosa, but was more extensive in the tumours. Cytoplasmic expression of Met was found in the majority of the tumours, and nuclear expression was found in 72%, including a high fraction of the cells located at the invasive front. Organotypic models with normal or malignant oral cells yielded principally similar results as in the mucosa and the cancers, respectively. A smaller amount of Met immunoreactivity was detected, by western blotting, in the nuclear fraction of cultured oral cancer cells. In conclusion, Met was upregulated in OSCCs and was also found in the nucleus. However, Met was not a marker for prognosis in this study.

Induction of invasion in an organotypic oral cancer model by CoCl2, a hypoxia mimetic.

Invasion is a hallmark of malignancy. The aim of this study was to develop an in vitro model that can be used for experimental studies of cancer cell invasion. The organotypic oral cancer model was constructed by growing oral squamous cell carcinoma (OSCC) cells on a collagen matrix in which normal human fibroblasts were incorporated. Immunohistochemical staining of the model showed that the expression of invasion-related molecules such as phosphorylated extracellular signal-regulated kinases 1 and 2 (p-ERK1/2), cyclooxygenase-2 (COX-2), p75(NTR), and hepatocyte growth factor receptor (Met) was similar to that seen in OSCC. Treatment of the model with cobalt chloride (CoCl(2)) to mimic hypoxic conditions increased cancer cell invasion, defined as the appearance of cancer cell islands protruding into the matrix. Models treated with CoCl(2) showed increased expression of p75(NTR) and laminin-5 in the cancer cells, and a more pronounced fragmentation of collagen IV in the basal membrane area, in contrast to models that were left untreated. The results indicate that the present model is well suited for studies on cancer cell invasion in the matrix and that the addition of CoCl(2) on day 3 of the experiment is indicated because it markedly increases the invasion and improves the model.

Epidermal growth factor-induced cyclooxygenase-2 expression in oral squamous cell carcinoma cell lines is mediated through extracellular signal-regulated kinase 1/2 and p38 but is Src and nuclear factor-kappa B independent.

The intracellular signalling cascade(s) mediating epidermal growth factor (EGF)-induced cyclooxygenase-2 (COX-2) expression is poorly defined in oral carcinomas. Investigation of two different oral squamous cell carcinoma (OSCC) cell lines with high EGF-induced COX-2 expression revealed, however, that this expression was dependent on two mitogen-activated protein kinase (MAPK) pathways [extracellular signal-regulated kinase 1/2 (ERK1/2) and p38] because combined inhibition of these pathways was needed to abolish EGF-induced COX-2 expression. Surprisingly, inhibition of phosphoinositide-3 kinase (PI3K) increased EGF-induced COX-2 expression in the basaloid OSCC cell line (C12), suggesting a PI3K-controlled, inhibitory COX-2-regulating pathway. Neither the transcription factor nuclear factor-kappaB (NF-kappaB), nor Src, was involved in EGF-induced COX-2 expression. The results suggest that EGF-induced COX-2 expression is regulated by several pathways, and emphasizes that individual tumors use different strategies for intracellular signalling.

c-Jun N-terminal kinase negatively regulates epidermal growth factor-induced cyclooxygenase-2 expression in oral squamous cell carcinoma cell lines.

Epidermal growth factor (EGF)-induced cyclooxygenase-2 (COX-2) expression in squamous cell carcinomas is mediated through the extracellular signal-regulated kinase 1/2 and p38 pathways. Examination of a basaloid and a conventional oral squamous cell carcinoma cell line revealed that inhibition of c-Jun N-terminal kinase (JNK) with SP600125 increased EGF-induced (but not basal) COX-2 transcription 1.5-1.9-fold in extracellular signal-regulated kinase 1/2 and p38 pathway-dependent manners. Although JNK may phosphorylate the cyclosporine A-sensitive transcription factor, nuclear factor of activated T cells c3, it was seemingly not involved because cyclosporine A did not reduce EGF-induced COX-2 expression. Thus, JNK negatively regulated EGF-induced extracellular signal-regulated kinase 1/2 and/or p38-mediated COX-2 transcription, presumably through activating an unidentified phosphatase.

Salivary trefoil factor 3 enhances migration of oral keratinocytes.

Trefoil factor 3 (TFF3) is a member of the mammalian TFF family. Trefoil factors are secreted onto mucosal surfaces of the entire body and exert different effects according to tissue location. Trefoil factors may enhance mucosal healing by modulating motogenic activity, inhibiting apoptosis, and promoting angiogenesis. Trefoil factor 3 is secreted from the submandibular gland and is present in whole saliva. The aim of this study was to assess the migratory and proliferative effects of TFF3 on primary oral human keratinocytes and oral cancer cell lines. The addition of TFF3 increased the migration of both normal oral keratinocytes and the cancer cell line D12, as evaluated by a two-dimensional scratch assay. By contrast, no increase in proliferation or energy metabolism was observed after stimulation with TFF3. Trefoil factor 3-enhanced migration was found to be driven partly by the extracellular signal-related kinase (Erk1/2) pathway, as shown by addition of the mitogen-activated protein kinase (MAPK) inhibitor PD 98059. Previous functional studies on trefoil peptides have all been based on cells from monolayered epithelium like the intestinal mucosa; this is the first report to show that normal and cancerous keratinocytes from stratified epithelium respond to TFF stimuli. Taken together, salivary TFF3 is likely to contribute to oral wound healing.

A study of phosphorylated ERK1/2 and COX-2 in early stage (T1-T2) oral squamous cell carcinomas.

BACKGROUND: Histomorphological grading at the invasive front of oral squamous cell carcinomas (OSCCs) may provide useful prognostic information. In the present study, we investigated the presence and prognostic value of activated phosphorylated extracellular signal-regulated kinases 1 and 2 (p-ERK1/2) and cyclo-oxygenase-2 (COX-2) both at the invasive front and in central/superficial parts of OSCCs. METHODS: Using immunohistochemistry, we assessed the presence of p-ERK1/2 and COX-2 in 53 early stage OSCCs. Clinical data were recorded prospectively. The end point was disease-free survival. RESULTS: p-ERK1/2 staining was present in almost all tumours. The staining was mostly nuclear in the cells of the invasive front and either nuclear or nuclear/cytoplasmic in central/superficial tumour parts. COX-2 was observed in almost all tumours (98%) and the staining was often restricted to focal areas. Most tumours were COX-2 negative at the invasive front. The lowest P-value in survival analyses was P = 0.06 for p-ERK1/2 at the invasive front. COX-2, the histomorphological grading systems and TNM stage were of no prognostic value. CONCLUSION: p-ERK1/2 was present in almost all tumours and p-ERK1/2 may be a prognostic marker at the invasive front of OSCCs. In early stage OSCCs, most tumours did not express COX-2 at the invasive front.

[Retraction of: Diagnostics and treatment of early stages of oral cancer]. / Tilbaketrekking av: Diagnostikk og behandling av forstadier til munnhulekreft.

The undersigned, who are co-authors of the article Diagnostics and treatment of early stages of oral cancer, wish to retract it. The reason is that the basis for the review article has been shown to be false. A review committee, that has assessed the research activity of the main author, has concluded that the data in this article are fabricated. We can no longer stand behind the article and hereby retract it.

The influence of resection and aneuploidy on mortality in oral leukoplakia.

BACKGROUND: Although the standard treatment of oral leukoplakia ranges from watchful waiting to complete resection, the value of these approaches is unknown. METHODS: We studied the relations among resection, ploidy status, and death from cancer in 103 patients with diploid dysplastic oral leukoplakia, 20 patients with tetraploid lesions, and 27 patients with aneuploid lesions. Data on cancer-specific mortality and treatment were obtained from the Cancer Registry of Norway, Statistics Norway, and chart reviews. RESULTS: Primary oral carcinoma developed in 47 of the 150 patients with leukoplakia (31 percent)--5 with diploid, 16 with tetraploid, and 26 with aneuploid leukoplakia--during a mean follow-up of 80 months (range, 4 to 237). The margin status of the initial leukoplakia resection had no relation to the development of oral cancer (P=0.95). Twenty-six of the 47 patients in whom cancer developed (4 with prior tetraploid and 22 with prior aneuploid lesions) had recurrences (55 percent); the recurrences were more frequently multiple and distant (within the oral cavity) among patients with aneuploid lesions than among those with tetraploid or diploid lesions. All 47 patients underwent a standard regimen of surgery and radiation, followed by chemotherapy in the 26 with recurrent cancer. Only patients with aneuploid leukoplakia died of oral cancer; the five-year rate of death from cancer was 72 percent. Aneuploidy-related first carcinomas were diagnosed at a more advanced stage than were carcinomas originating from diploid or tetraploid leukoplakia (P=0.03) and were more likely to be lethal regardless of the stage. CONCLUSIONS: Complete resection of aneuploid leukoplakia does not reduce the high risk of aggressive carcinoma and death from oral cancer.

Molecular based treatment of oral cancer.

Given the increase in the age distribution of the population, an increase in cancer incidence rates are to be expected. Oral cancer is a disfiguring disease that continues to increase in incidence, particularly in the young, and to an extent that cannot be fully explained by increased exposure to known risk factors. Despite extensive research on treatment modalities towards oral cancer, the 5-year survival rate of this disease has not been improved over the last 4-5 decades. These facts strongly favour chemoprevention-systemic medication to revert, stop, or delay the carcinogenic process-as an approach to treating oral cancer. A chemopreventive approach to oral cancer most likely should encompass a combination of drugs targeting metabolic pathways relevant to oral carcinogenesis. Candidate drugs are retinoids and selective inhibitors of cyclooxygenase-2, epidermal growth factor receptor (EGFR), and peroxisome proliferator activated receptors (PPARs). Chemopreventive trials so far have used surrogate intermediate biomarkers as measurement of treatment effect. However, the efficiency of any drug for chemopreventive use should be assessed through a prospective randomized trial and evaluated by the only definitive end point for prevention of cancer, the incidence rates of new carcinomas.

Cyclooxygenase-2 (COX-2) expression in high-risk premalignant oral lesions.

Emerging data indicate a link between genetic instability and up-regulation of cyclooxygenase-2 (COX-2). To see if individuals at high risk of oral cancer are candidates for treatment with selective COX-2 inhibitors (coxibs), levels of COX-2 expression in healthy, premalignant and cancerous oral mucosa were compared with the occurrence of DNA ploidy status as a genetic risk marker of oral cancer. COX-2 gene product was evaluated immunohistochemically in 30 healthy persons, in 22 patients with dysplastic lesions without previous or concomitant carcinomas, and in 29 patients with oral carcinomas. The immunohistochemical findings were verified by western blotting. COX-2 expression was correlated to DNA content as a genetic risk marker of oral cancer. COX-2 was up-regulated from healthy to premalignant to cancerous oral mucosa. Thus, COX-2 expression was found in 1 case of healthy oral mucosa (3%). All specimens from healthy mucosa had a normal DNA content. In patients with premalignancies. In 29 patients with oral carcinomas, cyclooxygenase-2 expression was observed in 26 (88%), and aneuploidy was observed in 25 cases (94%, P=0.04). Notably, of 22 patients with dysplastic lesions, COX-2 was exclusively expressed in a subgroup of nine patients (41%) identified to be at high risk of cancer by the aberrant DNA content of their lesions. Seven of these patients were followed for 5 years or more. An oral carcinoma developed in six of them (85%; P=0.02). These findings emphasize the need to determine whether coxibs can reduce the risk of oral cancer in patients with high-risk precancerous lesions.

Detection of malignant epithelial cells in effusions using flow cytometric immunophenotyping: an analysis of 92 cases.

We compared the efficiency of immunophenotyping using flow cytometry (FCM) and a combination of morphologic and immunocytochemical studies for detecting malignant cells in 92 effusions. Cytologic results were as follows: carcinoma cells, 43 specimens; benign, 42 specimens; suggestive of nonepithelial malignancy, 7 specimens. After immunocytochemical analysis, 5 benign specimens were reclassified as malignant and 4 malignant epithelial specimens as benign. With FCM, cells positive for Ber-EP4, B 72.3, AH6, and HB-TN were detected in 28 to 36 (64%-82%) of 44 carcinomas but only 2 to 12 (5%-29%) of 41 benign specimens. Significant association was seen for coexpression. Ber-EP4 and AH6 were the most sensitive; Ber-EP4 was the most specific. The presence of cells positive for 3 of 4 markers strongly suggested malignancy (34/44 carcinoma specimens [77%]; 3/41 reactive specimens [7%]). The presence of cells positive for all 4 markers was diagnostic of malignancy (17/44 malignant specimens [39%]; 0/41 reactive effusions [0%]). FCM and immunocytochemical resultsfor Ber-EP4 expression showed excellent association. FCM is a powerful tool for diagnosing difficult effusions and can quantify coexpression of various markers in fresh specimens. By using established cellular markers coupled with biological markers, FCM also has great promise for experimental purposes.

Interleukin-8 and vascular endothelial growth factor mRNA and protein levels are down-regulated in ovarian carcinoma cells in serous effusions.

Angiogenic factors are involved in tumor growth and spread. The aim of this study was to evaluate the expression of angiogenesis-related genes in malignant serous effusions of patients with advanced-stage (FIGO stage III and IV) ovarian carcinoma. In addition, to compare the results for carcinoma cells in effusions with corresponding primary tumors and metastatic lesions, and analyze their prognostic role. Sections from 66 effusions and 90 primary and metastatic lesions from 62 ovarian and primary peritoneal carcinoma patients, were evaluated for expression of basic fibroblast factor (bFGF), interleukin-8 (IL-8), and vascular endothelial growth factor (VEGF) using mRNA in situ hybridization (ISH). Protein expression was evaluated in a subset of specimens using immunohistochemistry (IHC). ISH results were correlated with clinical parameters. In both effusions and solid tumors, bFGF mRNA was the most commonly expressed factor (93% of effusions and 95% of solid tumors) followed by IL-8, while VEGF was expressed in a minority of the specimens (P < 0.001 for bFGF vs. IL-8 and VEGF). In solid tumors, angiogenic mRNA expression was seen in both tumor and stromal cells in the majority of positive cases. ISH results did not differ in primary and metastatic tumors. However, carcinoma cells in effusions showed down-regulated expression of VEGF, when compared with both primary tumors (P = 0.029) and metastases (P = 0.015). IL-8 showed a similar down-regulation in effusions, when compared with metastases (P = 0.005). IHC showed excellent agreement with mRNA findings on protein level. In the study of clinico-pathologic parameters, IL-8 mRNA expression in effusions was associated with higher tumor grade (P = 0.044). Angiogenic gene expression in effusions showed no correlation with patient age, previous treatment, residual tumor size, FIGO stage or disease outcome in survival analysis (P > 0.05). Peritoneal and pleural effusions showed similar expression patterns. In conclusion, bFGF is the major angiogenic factor expressed in ovarian carcinoma at the mRNA level. It is highly expressed in both solid tumors and serous effusions, while IL-8 and VEGF are down regulated in carcinoma cells in effusions, possibly due to the lack of interaction with stromal cells. mRNA expression of VEGF, bFGF, and IL-8 does not appear to be a predictor of disease outcome in advanced-stage ovarian carcinoma. Carcinoma cells in pleural and peritoneal effusions show a similar metastatic expression profile, in agreement with our previous findings, supporting the true metastatic nature of ovarian carcinoma cells in ascites.

Caveolin-1 expression in ovarian carcinoma is MDR1 independent.

We studied the role of caveolin-1 in tumor progression and prognosis in serous ovarian carcinoma and the association between caveolin-1 and MDR1 expression. The study involved immunohistochemical analysis for caveolin-1 and P-glycoprotein (P-gp) expression in 75 effusions and 90 solid lesions from ovarian and primary peritoneal carcinoma; in situ hybridization for MDR1 messenger RNA (mRNA) expression in 62 effusions and all 90 tumors; and reverse transcription-polymerase chain reaction (RT-PCR) for caveolin-1 mRNA expression in 23 effusions. Immunohistochemical analysis localized caveolin-1 to the cell membrane in 43 effusions and 24 tumors. P-gp membrane expression was detected in 14 effusions and 11 tumors; MDR1 mRNA, in 20 effusions and 30 tumors. Caveolin-1 mRNA was expressed in 19 effusions. Caveolin-1 protein expression showed no association with that of P-gp protein or MDR1 mRNA. The expression of all markers was similar in carcinoma cells in pleural and peritoneal effusions. Caveolin-1 is a novel diagnostic marker for effusions; expression is moderately elevated in tumor cells in effusions, possibly owing to altered signal transduction and metabolism in cancer cells at this site. Expression seems MDR1 independent.