Clear cell carcinoma has an expression pattern of cell cycle regulatory molecules that is unique among ovarian adenocarcinomas

BACKGROUND: The purpose of this study was to identify biologic differences between ovarian clear cell carcinoma and other ovarian adenocarcinomas by comparing the expression of cell cycle regulatory molecules and by analyzing the survival of the patients. METHODS: In 51 cases of epithelial ovarian carcinoma, the expression of the cell proliferation marker Ki-67 and that of the cell cycle regulatory molecules p53, p16, p21, p27, cyclin E, and cyclin A was studied using immunohistochemical techniques. The correlations among clinical stage, histologic subtype, labeling index for Ki-67, and expression of these cell cycle regulators were examined statistically. Multivariate survival analysis was performed using these factors in the Cox proportional hazards model. RESULTS: Clear cell carcinoma revealed such trends as low expression of both p53 and cyclin A and significantly increased expression of both p21 and cyclin E (compared with the other histologic subtypes). In all ovarian carcinomas, a very strong positive correlation (correlation coefficient 0.79; P < 0.0001) between p53 positive staining and cyclin A positive staining and a weak positive correlation (correlation coefficient 0.47; P < 0.01) between p21 positive staining and cyclin E positive staining were recognized at the level of expression of cell cycle regulatory molecules. Clinical stage was the only independent predictive factor for the survival of the patients. CONCLUSIONS: Among ovarian adenocarcinomas, clear cell carcinoma exhibits a unique pattern of expression of cell cycle regulatory molecules, though in this study the survival of the patients did not correlate with histologic subtype, only with clinical stage.     

Karyotypic abnormalities in adenocarcinomas of the lung

Cytogenetic analysis of 114 adenocarcinomas of the lung revealed clonal abnormalities in 67 tumors. The chromosome numbers ranged from near-diploid to hypertetraploid. Clonal abnormalities seen as the sole anomaly were loss of the Y chromosome (21 tumors), trisomy 7 (2 tumors), and trisomy 12 (1 tumor). A supernumerary ring chromosome was the only clonal change in 4 tumors. The bands most often affected were 17p11-13 (13 cases), 1q10-12 and 1p22 (10 cases each), 1p11-13 and 1q21 (9 cases each), and 11p11, 11p15 and 15p11-13 (6 cases each). The chromosomes most frequently involved in structural rearrangements were chromosomes 1 (30 cases), 11 (20 cases), 3 (17 cases), 17 and 7 (16 cases each). Repeated loss of material from chromosome arms 1p, 3p, 6q, 11p, and 17p and gains of 1q were found. Recurrent structural changes were del(1)(p22) and i(5)(p10) (5 cases each) i(1)(q10), i(13)(q10), i(14)(q10) and del(17)(p11) (3 cases each). We found no abnormalities that seemed to be specifically associated with pulmonary adenocarcinomas, but isochromosomes i(1)(q10), i(5)(p10) and i(13)(q10) and changes of 6q were present in our series at frequencies higher than those generally seen in the other main types of lung cancer.     

Increased C-CRK proto-oncogene expression is associated with an aggressive phenotype in lung adenocarcinomas

The C-CRK gene, cellular homolog of the avian v-crk oncogene, encodes two alternatively spliced adaptor signaling proteins, CRKI (28 kDa) and CRKII (40 kDa). Both CRKI and CRKII have been shown to activate kinase signaling and anchorage-independent growth in vitro and CRKI transformed cells readily form tumors in nude mice. Affymetrix oligonucleotide arrays were used to analyse 86 lung adenocarcinomas and 10 uninvolved lung tissues. C-CRK mRNA expression was increased in more advanced (stage III versus stage I), larger (T(2-4) versus T(1)), and poorly differentiated tumors and in tumors from patients demonstrating poor survival (P=0.00034). An overlapping series of 93 lung adenocarcinomas (64 stage I and 29 stage III) and 10 uninvolved lung specimens were measured for quantitative differences in CRKI and CRKII protein levels using 2-D PAGE. CRK protein spots were identified using mass spectrometry and 2-D Western blotting. A significant increase in levels of the CRKI oncoprotein and the phosphorylated isoform of CRKII was observed in tumors (P<0.05). No difference in protein level was evident between stages. Concordant with mRNA expression, CRKI and CRKII were increased in poorly differentiated tumors (P<0.05). CRK immunohistochemical analysis of tumor tissue arrays using the same tumor series also demonstrated increased abundance of nuclear and cytoplasmic CRK in more proliferative tumors (P<0.05). This study provides the first quantitative analysis of discrete CRKI and CRKII protein isoforms in human lung tumors and provides evidence that the C-CRK proto-oncogene may foment a more aggressive phenotype in lung cancers.     

Centrosome abnormalities in ovarian cancer

Centrosome abnormalities have been found in various cancer types and are thought to be involved in early development of cancer and/or progression. The contribution of centrosome abnormalities to ovarian tumorigenesis has not been previously evaluated. We sought to determine whether centrosome dysfunction occurs in ovarian tumorigenesis, and whether it could be used as an indicator of early neoplastic changes in ovarian surface epithelium (OSE). Primary cultures of normal OSE and ovarian tumors, as well as paraffin-embedded normal ovaries and ovarian tumors of different stages, were used for immunostaining with a gamma-tubulin antibody. Centrosomes were considered abnormal if there were more than 2 per cell, if their sizes were greater than 2-fold of a normal centrosome, and/or if they were abnormal in shape. Centrosomes in normal tissue were uniform in size, whereas centrosomes in ovarian tumors tended to be abnormal in size, number and shape. On average, 4.7% of cells in 5 primary normal OSE cultures had more than 2 centrosomes, whereas 14.1% of primary cells from 5 ovarian tumors displayed centrosome abnormalities (p = 0.008). Centrosome abnormalities were present in 60.9% of stage I (n = 23), 83.3% of stage II (n = 30) and all stage III (n = 10) paraffin-embedded ovarian tumor samples examined, but not in normal tissues. In addition, centrosome abnormalities occurred more frequently in ovarian tumors with higher grade and aggressive serous subtype. This is the first demonstration that centrosome abnormalities occur in ovarian tumors. Centrosome dysfunction may be an early event in ovarian carcinogenesis and involved in ovarian tumor progression.     

Immunological reactivity of mucinous and serous ovarian adenocarcinomas

Comparison of immunological reactivity of glycoprotein antigens extracted from individual cases of mucinous and serous ovarian adenocarcinomas was performed taking into account the immunological relationship with carcinoembryonic antigen (CEA), nonspecific cross-reacting antigen (NCA), alpha-1-antichymotrypsin, and alpha-1-acid glycoprotein. In all immunological tests, the specific immune sera against perchloric acid extracts of ovarian mucinous and serous cystadenocarcinomas and antisera against the reference antigens mentioned above were used. It was established that: 1) ovarian mucinous and serous adenocarcinomas are immunologically different and possess various tumor-associated antigens, 2) ovarian mucinous adenocarcinomas contain considerable amounts of CEA and NCA, whereas serous type neoplasms show negligible amounts or lack of these antigens; and 3) in both types of tumors, alpha-1-antichymotrypsin and alpha-1-acid glycoprotein activities are found. Immunological data indicate that ovarian mucinous and serous adenocarcinomas derive from separate lineages of epithelium.     

High level expression of fms proto-oncogene mRNA is observed in clinically aggressive human endometrial adenocarcinomas

Six micron paraffin sections of paraformaldehyde-fixed endometrial currettings of 21 benign and neoplastic endometrial specimens were assayed for tumor cell-specific oncogene expression by in situ hybridization with probes for six oncogenes, beta-actin, and the E. coli plasmid pBR322. In the benign hyperplasias and invasive adenocarcinomas, multiple oncogenes, including erbB, fms, c-myc, and Ki-ras were expressed at significant levels. For the adenocarcinomas, statistical analysis demonstrated that high levels of expression of fms-complementary mRNA correlated strongly with clinicopathologic features (high FIGO histologic grade, high FIGO clinical stage, deep myometrial penetration) predictive of aggressive clinical behavior and poor outcome. The authors discuss the role which M-CSF receptor (the fms gene product) and locally-produced M-CSF may play in the development of the observed aggressively-malignant phenotypes. They also propose that pre-hysterectomy assay of fms gene expression in endometrial currettings in FIGO Stage I patients might be clinically useful to help identify preoperatively those patients with deep myometrial penetration or other locoregional spread.     

Kinetics of cisplatin-induced apoptosis in murine mammary and ovarian adenocarcinomas

There is mounting evidence to indicate that the mode of cell death known as apoptosis plays an important role in cancer therapy. Most supporting observations have come from experiments conducted in vitro, and it is important to extend such studies to in vivo systems. We have therefore evaluated the magnitude and kinetics of apoptosis induction in tumors from mice treated with cisplatin (CP). Two transplantable murine tumors were studied: a mammary adenocarcinoma, MCa-4, and an ovarian adenocarcinoma, OCa-l. Tumor-bearing mice were injected with various doses of CP, and specimens were obtained over several days. Apoptosis was scored by morphometric analysis of histological sections of the tumors using the features characteristic of cells undergoing this mode of cell death. The results showed a significant apoptotic response in both tumors within a few hours after injection of the drug. The kinetics were very broad, with apoptotic cells present over essentially the entire time course studied. Dose-response relationships for CP-induced apoptosis were compared to the tumor response measured in terms of tumor growth delay.     

Mutation analysis of the c-mos proto-oncogene in human ovarian teratomas.

Female transgenic mice lacking a functional c-mos proto-oncogene develop ovarian teratomas, indicating that c-mos may behave as a tumour-suppressor gene for this type of tumour. We have analysed the entire coding region of the c-MOS gene in a series of human ovarian teratomas to determine whether there are any cancer-causing alterations. DNA from twenty teratomas was analysed by single-strand conformational analysis (SSCA) and heteroduplex analysis (HA) to screen for somatic and germline mutations. In nine of these tumours the entire gene was also sequenced. A previously reported polymorphism and a single new sequence variant were identified, neither of which we would predict to be disease-causing alterations. These results suggest that mutations in the coding region of the c-MOS gene do not play a significant role in the genesis of human ovarian teratomas.     

Frequent occurrence of Ha-rasl allelic deletion in human ovarian adenocarcinomas.

Fourteen human adenocarcinoma specimens were analyzed for somatic abnormalities affecting genes of the ras family. No amplification of the 3 ras genes was detected. Allelic deletion of the Ha-rasl gene (11p15.5) was found to be a very common abnormality in human ovarian adenocarcinomas (4 out of 7 informative cases). However, in these neoplasm deletion of a presumed normal Ha-rasl allele is not a contributory factor in strengthening the tumorigenic effect of a mutated allele. More probably, Ha-rasl allelic losses are markers of larger chromosomal deletions. Analyses at gamma globin loci (11p15.5) and int-2 locus (11q13) provided evidence that the deletions may extend from Ha-rasl locus towards the centromere but never involve loss of the entire chromosome 11. These findings may suggest that a putative tumor suppressor gene closely linked to Ha-rasl in 11p15.5 is involved in ovarian cancerogenesis.     

Reduced expression of intercellular adhesion molecule-1 in ovarian adenocarcinomas.

Ovarian adenocarcinomas develop as the result of multiple genetic and epigenetic changes in the precursor ovarian surface epithelial (OSE) cells which result in a malignant phenotype. We investigated changes in gene expression in ovarian adenocarcinoma using a cDNA array containing 588 known human genes. We found that intercellular adhesion molecule-1 (ICAM-1) was expressed at lower levels in the ovarian tumour cell lines OAW42, PEO1 and JAM than in the immortalised human ovarian surface epithelial cell line HOSE 17.1. Further investigation revealed ICAM-1 was expressed in the surface epithelium of normal ovaries and both mRNA and protein expression levels were reduced in the majority of ovarian adenocarcinoma cell lines and primary tumours. ICAM-1 expression was increased in 8/8 cell lines treated with the de novo methyltransferase inhibitor 5-aza-2'-deoxycytidine, indicating that methylation of CpG islands may play a role in the down-regulation of its expression in primary tumours. There was a significant association between patients whose tumours expressed ICAM-1 and survival (P = 0.03), suggesting that expression levels of ICAM-1 may have clinical relevance.     

Point mutation of the c-Ki-ras proto-oncogene and the p53 tumour suppressor gene in distal colonic adenocarcinomas

One hundred and twenty-seven monochronous primary colorectal adenocarcinomas were examined for both activation of the c-Ki-ras proto-oncogene by point mutation in codons 12 or 13 and inactivation of the p53 tumour suppressor gene by point mutation in exons four through nine. All of the carcinomas originated in the distal half of the colorectum. Activation of the c-Ki-ras proto-oncogene was detected in 23% (29/127) of adenocarcinomas, and p53 inactivation was detected in 63% (80/127) of adenocarcinomas. Only 16% (20/127) of cases exhibited both genetic changes, and no association was noted between the occurrence of these two changes. Individually, both ras activation and p53 inactivation were associated with a poorer patient prognosis (p=0.0009 and p=0.0159 respectively). In a Cox regression analysis both ras activation and p53 inactivation contributed independently towards patient mortality. These results suggest that mutations exert their effect independently of each other, and that it is the cumulative mutational load that determines a patient's prognosis.     

Expression of the HER-2/neu proto-oncogene in serous ovarian neoplasms.

BACKGROUND. It is unclear whether HER-2/neu proto-oncogene expression in ovarian epithelial neoplasms is related to prognosis. METHODS. The authors performed immunohistochemical stains on 20 serous tumors of low malignant potential (STLMP) in Stages I and II and 19 serious carcinomas in the same stages. They used three different commercial antibodies to make comparisons. RESULTS. Two of four Stage I STLMP in patients who experienced disease progression showed positive staining for the gene product, whereas none of seven Stage I nonprogressive STLMP showed positive staining. Five of the six Stage III nonprogressive STLMP showed positive staining, whereas none of three Stage III STLMP that progressed showed positive staining. Three carcinomas (one Stage I and two Stage III) also showed positive staining. CONCLUSIONS. Expression of HER-2/neu may be associated with high stage in serous ovarian neoplasms, but it is not likely to identify the small fraction of patients with STLMP who will experience disease progression.     

microRNA expression profiling of endometrial endometrioid adenocarcinomas and serous adenocarcinomas reveals profiles containing shared, unique and differentiating groups of microRNAs

microRNAs (miRNAs) control a multitude of pathways in human cancers. Differential expression of miRNAs among different histological types of tumors within the same type of tissue offers insight into the mechanism of pathogenesis and may help to direct treatment to improve prognosis. We assessed expression of 667?miRNAs in endometrial endometrioid and serous adenocarcinomas using RNA extracted from benign endometrium as well as from primary endometrial tumors. Quantitative miRNA profiling of endometrial adenocarcinomas revealed four overlapping groups of significantly overexpressed and underexpressed miRNAs. The first group was composed of 20?miRNAs significantly dysregulated in both adenocarcinoma types compared with benign endometrium, two groups were composed of miRNAs significantly dysregulated in either endometrioid adenocarcinomas or in serous adenocarcinomas compared with benign endometrium, and the fourth group was composed of 17?miRNAs that significantly distinguished between endometrioid adenocarcinomas and serous adenocarcinomas themselves. Validation of the expression levels of the selected miRNAs was carried out in a second panel composed of ten endometrioid and five serous tumors. Experimentally validated mRNA targets of these dysregulated miRNAs were identified using published sources, whereas TargetScan was used to predict targets of miRNAs in the first and fourth profile groups. These validated and potential miRNA target lists were filtered using published lists of genes displaying significant overexpression or underexpression in endometrial cancers compared to benign endometrium. Our results revealed a number of dysregulated miRNAs that are commonly found in endometrial (and other) cancers as well as several dysregulated miRNAs not previously identified in endometrial cancers. Understanding these differences may permit the development of both prognostic and diagnostic biomarkers.     

Four potential biomarkers as prognostic factors in stage III serous ovarian adenocarcinomas

The mortality rate for patients with ovarian carcinomas is high and the available prognostic factors are insufficient. The use of biomarkers may contribute to better prediction and survival for these patients. We aimed to study the gene and protein expressions for 7 potential biomarkers, to determine if it is possible to use them as prognostic factors. Genes selected from our previous microarray analysis (2006), CLU, ITGB3, TACC1, MUC5B, CAPG, PRAME and TROAP, were analyzed in 19 of the tumors with quantitative real-time polymerase chain reaction (QPCR). We found that CLU and ITGB3 were more expressed in tumors from survivors and PRAME and CAPG were more expressed in tumors from deceased patients. None of the other 3 genes were significantly differently expressed. The protein expressions of CLU, ITGB3, PRAME and CAPG were analyzed in 43 of the tumors with western blot for semiquantitative analysis. We established that the mRNA and protein expressions correlated and that all 4 proteins were significantly differently expressed. Further, immunohistochemistry (IHC) was used to localize the expression of the proteins in the tumor samples. According to our results, the 4 biomarkers CLU, ITGB3, PRAME and CAPG may be used as prognostic factors for patients with stage III serous ovarian adenocarcinomas.     

Genetic aberrations detected by comparative genomic hybridization in ovarian clear cell adenocarcinomas

Genetic abnormalities were detected by comparative genomic hybridization (CGH) in 12 ovarian clear cell adenocarcinomas. DNA sequence copy number abnormalities (CNAs) occurring in more than 20% of the cancers included increased copy numbers of 8q11-q13, 8q21-q22, 8q23, 8q24-qter, 17q25-qter, 20q13-qter and 21q22-qter and reduced copy numbers of 19p. Increases in copy numbers of 8q11-q13, 8q21-q22, 8q23 and 8q24-qter occurred more frequently in disease-free patients than in recurrent/non-surviving patients (p < 0.05). However, increases in copy numbers of 17q25-qter and 20q13-qter occurred more frequently in recurrent/non-surviving patients than in disease-free patients (p < 0.05). Furthermore, increases in copy numbers of 17q25-qter and 20q13-qter occurred together (p < 0.05). Additionally, there were negative correlations between increases in copy numbers of 8q21-q22 and 17q25-qter, and between 8q21-q22 and 20q13-qter (p < 0.05). It appears that ovarian clear cell adenocarcinomas can be classified into two subtypes, one being cancer with an increase in copy numbers of 8q and the other being cancer with increases in copy numbers of 17q25-qter and 20q13-qter.     

Karyotypic pattern of pancreatic adenocarcinomas correlates with survival and tumour grade

The relationship between cytogenetic findings and clinico-histopathological parameters was assessed in 29 patients with pancreatic adenocarcinoma. Karyotypic analysis revealed normal karyotypes (N) in 8 carcinomas and abnormal karyotypes (A) in 21. Within the A group, 8 cases had simple chromosome abnormalities (As), i.e., only one numerical or structural aberration, whereas 13 had complex changes with multiple numerical and structural abnormalities (Ac). No significant differences between the N and A groups were detected in terms of tumour grade, clinical stage, type of surgery performed, tumour site or size or the patient's age and survival. A correlation analysis between groups As and Ac revealed a significant difference with regard to grade, poorly differentiated carcinomas being more frequent in the Ac group. Patients in the Ac group had also a significantly shorter survival time than those in the As group. None of the other potentially prognostic parameters, i.e., grade, tumour site, stage and type of surgery performed, correlated significantly with clinical outcome. © 1994 Wiley-Liss, Inc.     

Low-grade serous ovarian cancer: a unique disease

Low-grade serous carcinomas represent approximately 10% of all serous ovarian carcinomas. A growing body of research has demonstrated several important differences between the clinical and molecular characteristics of these tumors and those of high-grade serous ovarian carcinomas. Patients with low-grade serous ovarian tumors are diagnosed at a younger age, have a longer overall survival, and have lower response rates to conventional chemotherapy. In addition, low-grade serous ovarian carcinomas have pathologic and molecular characteristics distinct from high-grade serous carcinomas, yet similar to serous tumors of low malignant potential. This suggests a common pathogenesis and a continuum of disease from serous tumors of low malignant potential to low-grade serous carcinomas. Further study, focusing specifically on low-grade serous carcinomas, is needed to determine the role of other chemotherapeutic agents, hormonal therapy, or targeted biologic agents in the treatment of this disease.     

Molecular analysis of breaks in BCL-1 proto-oncogene in B-cell lymphomas with abnormalities of 11q13

The t(11;14)(q13;q32) is a recurring translocation that occurs infrequently but non-randomly in B-cell chronic lymphocytic leukemia, B-cell non-Hodgkin's lymphoma, and multiple myeloma. The putative oncogene BCL-1 located at the chromosomal band 11q13 has been cloned previously from a B-cell CLL with t(11;14). We studied the molecular structure of the BCL-1 gene in eight B-cell NHL tumors that exhibited a break at 11q13. The cytogenetic changes in these tumors were t(11;14) in three, t(1;11;14)(q32;q13;q32) in two and dup(11)(pter----q23::11q13----ter) in three. The BCL-1 gene was found to have rearranged in two tumors. By Southern blot analysis of single and double digested DNA from placenta and from the tumors, we mapped the breakpoint in BCL-1 to a 0.5 kb Pst-I-HindIII restriction fragment which was approximately 2kb away from the sites of previously mapped breakpoints. Sequential hybridization of Southern blots of these tumors with different immunoglobulin probes (for J region, Cu, Su) and BCL-1 probe identified co-migrating fragments with Su probe after BamHI restriction digestion. These results demonstrate that translocation breaks in the BCL-1 gene are not clustered in a short stretch of DNA at 11q13, and that the translocation related breaks in the immunoglobulin heavy chain can occur outside the joining region. The implications of these observations to the genesis of chromosomal translocations during B cell development are discussed.