Rapid onset of pituitary apoplexy after goserelin implant for prostate cancer: need for heightened awareness

No Abstract

Nerve growth factor stimulates proliferation and survival of human breast cancer cells through two distinct signaling pathways

We show here that the neurotrophin nerve growth factor (NGF), which has been shown to be a mitogen for breast cancer cells, also stimulates cell survival through a distinct signaling pathway. Breast cancer cell lines (MCF-7, T47-D, BT-20, and MDA-MB-231) were found to express both types of NGF receptors: p140(trkA) and p75(NTR). The two other tyrosine kinase receptors for neurotrophins, TrkB and TrkC, were not expressed. The mitogenic effect of NGF on breast cancer cells required the tyrosine kinase activity of p140(trkA) as well as the mitogen-activated protein kinase (MAPK) cascade, but was independent of p75(NTR). I, contrast, the anti-apoptotic effect of NGF (studied using the ceramide analogue C2) required p75(NTR) as well as the activation of the transcription factor NF-kB, but neither p140(trkA) nor MAPK was necessary. Other neurotrophins (BDNF, NT-3, NT-4/5) also induced cell survival, although not proliferation, emphasizing the importance of p75(NTR) in NGF-mediated survival. Both the pharmacological NF-KB inhibitor SN50, and cell transfection with IkBm, resulted in a diminution of NGF anti-apoptotic effect. These data show that two distinct signaling pathways are required for NGF activity and confirm the roles played by p75(NTR) and NF-kappaB in the activation of the survival pathway in breast cancer cells.

Proteomic analysis reveals that 14-3-3 sigma in downregulated in human breast cancer cells

The class of molecular chaperones known as 14-3-3 is involved in the control of cellular growth by virtue of its apparent regulation of various signaling pathways, including the Raf/mitogen-activated protein kinase pathway. In breast cancer cells, the sigma form of 14-3-3 has been shown to interact with cyclin-dependent kinases and to control the rate of entry into mitosis. To test for a direct role for 14-3-3 in breast epithelial cell neoplasia, me have quantitated 14-3-3 protein levels using a proteomic approach based on two-dimensional electrophoresis and matrix-assisted laser desorption/ionization mass spectrometry (MALDI-TOF). We show here that 14-3-3 sigma protein is strongly down-regulated in the prototypic breast cancer cell lines MCF-7 and MDA-MB-231 and in primary breast carcinomas as compared with normal breast epithelial cells. In contrast, levels of the alpha, beta, delta, or zeta isoforms of 14-3-3 mere the same in both normal and transformed cells. The data support the idea that 14-3-3 sigma is involved in the neoplastic transition of breast epithelial cells by virtue of its role as a tumor suppressor; as such, it may constitute a robust marker with clinical efficacy for this pathology.

Proteomics of breast cancer for marker discovery and signal pathway profiling

Breast cancer is the most common form of cancer among women and the identification of markers to discriminate tumorigenic from normal cells, as well as the different stages of this pathology, is of critical importance. Two-dimensional electrophoresis has been used before for studying breast cancer, but the progressive completion of human genomic sequencing and the introduction of mass spectrometry, combined with advanced bioinformatics for protein identification, have considerably increased the possibilities for characterizing new markers and therapeutic targets. Breast cancer proteomics has already identified markers of potential clinical interest (such as the molecular chaperone 14-3-3 sigma) and technological innovations such as large scale and high throughput analysis are now driving the field. Methods in functional proteomics have also been developed to study the intracellular signaling pathways that underlie the development of breast cancer. As illustrated with fibroblast growth factor-2, a mitogen and motogen factor for breast cancer cells, proteomics is a powerful approach to identify signaling proteins and to decipher the complex signaling circuitry involved in tumor growth. Together with genomics, proteomics is well on the way to molecularly characterizing the different types of breast tumor, and thus defining new therapeutic targets for future treatment.

Young patients with colorectal cancer: How do they fare?

Background: Younger patients with colorectal cancer (CRC) have long been thought to have a poorer prognosis than older patients. Recent overseas reports, however, have disputed this. The aim of the present study was to conduct a review of data on patients with colorectal cancer collected over a 29-year period at Princess Alexandra Hospital (PAH) to ascertain the outcome of a younger subset of patients at this hospital. Methods: The PAH Colorectal Project records on 2495 patients with malignancies of the colon, rectum and anus who were treated and followed since 1971, were analysed to determine clinical presentation, treatment and outcome. A group of 61 patients with colo-rectal adenocarcinoma was identified who were aged less than 40 years at presentation. Their clinical data were then compared with the larger group of older patients. Results: There were 30 male and 31 female patients in the younger group. A positive family history was the most consistent risk factor, present in 34% of patients. Despite this, only one patient out of 61 had been diagnosed as a result of a screening programme. The Australian Clinico-Pathological Stage (ACPS), histology and distribution of tumours corresponded to that of the older patients. The overall 5-year survival among younger patients was 53%. The 5-year survival rates in younger patients were better than that for older patients for ACPS A and B, reaching statistical significance for both of these stages. Conclusions: Our results indicate that younger patients with colorectal cancer have the potential to do just as well as older ones. With the influence of a family history of colorectal cancer being very apparent in this group, greater emphasis should be placed on an adequate screening programme for them.

Human trypsinogen in colorectal cancer

Trypsinogen (TRY), the precursor to the serine protease trypsin, is found in the pancreas and mediates digestive proteolysis in the small intestine. Differential display of cDNAs expressed by human colorectal tumor tissues compared with adjacent normal colonic mucosa identified an isoform of TRY (TRY2) up-regulated in colorectal cancers. Northern blot analysis of RNA isolated from a series of 28 malignant colon tumors and corresponding normal mucosa showed that TRY transcripts were up-regulated 2- to 33-fold in 29% of tumors. Further, TRY mRNA was expressed in 6 colorectal cancer cell lines, with highest levels detected in the metastatic tumor lines SW620 and HT29. Immunostaining for TRY protein expression showed intense immunoreactivity in the supranuclear cytoplasm of colon tumors in 16% of tissue specimens. To evaluate the relative contributions of 2 isoforms of TRY, TRY1 and TRY2, to total TRY mRNA expression, a semiquantitative multiplex RT-PCR assay was developed. TRY2 mRNA was detected in all 6 colorectal tumor cell lines, whereas TRY1 mRNA was expressed only in the metastatic tumor lines, showing that the high levels of TRY expression in the metastatic tumor lines are likely due to up-regulation of TRY1. Evaluation of TRY1 and TRY2 mRNA expression by multiplex RT-PCR in a series of 20 colon tumor tissues representative of the range of tumor progression showed that TRY2 mRNA was expressed much more commonly than TRY1 mRNA in normal mucosa (26% vs. 6%) as well as in primary tumor tissues (65% vs. 15%). These data demonstrate that TRY2 is the dominant TRY in colon tissue and suggest that up-regulation of TRY1 expression in colon tumors may be associated with a metastatic phenotype. (C) 2001 Wiley-Liss, Inc.

Characterization of a novel gene, STAG1/PMEPA1, upregulated in renal cell carcinoma and other solid tumors

Using differential display-polymerase chain reaction, we identified a novel gene sequence, designated solid tumor-associated gene 1 (STAG1), that is upregulated in renal cell carcinoma (RCC). The full-length cDNA (4839 bp) encompassed the recently reported androgen-regulated prostatic cDNA PMEPA1 and so we refer to this gene as STAG1/PMEPA1, Two STAG1/PMEPA1 mRNA transcripts of approximately 2.7 an 5 kb, with identical coding regions but variant 3' untranslated regions, were predominantly expressed in normal prostate tissue and at lower levels in the ovary. The expression of this gene was upregulated in 87% of RCC samples and also was upregulated in stomach and rectal adenocarcinomas. In contrast, STAG1/PMEPA1 expression was barely detectable in leukemia and lymphoma samples, Analysis of expressed sequence tag databases showed that STAG1/PMEPA1 also was expressed in pancreatic, endometrial, and prostatic adenocarcinomas. The STAG1/PMEPA1 cDNA encodes a 287-amino-acid protein containing a putative transmembrane domain and motifs that suggest that it may bind src homology 3- and tryptophan tryptophan domain-containing proteins. This protein shows 67% identity to the protein encoded by the chromosome 18 open reading frame 1 gene. Translation of STAG1/PMEPA1 mRNA in vitro showed two products of 36 and 39 kDa, respectively, suggesting that translation may initiate at more than one site. Comparison to genomic clones showed that STAG1/PMEPA1 was located on chromosome 20q13 between microsatellite markers D20S183 and D20S173 and spanned four exons and three introns. The upregulation of this gene in several solid tumors indicated that it may play an important role in tumorigenesis. (C) 2001 Wiley-Liss, Inc.

Safety and efficacy of low anterior en bloc resection as part of cytoreductive surgery for patients with ovarian cancer

Objective. To examine the feasibility and safety of a low anterior resection of the rectosigmoid plus adjacent pelvic tumour as part of primary cytoreduction for ovarian cancer. Methods. This study included 65 consecutive patients with primary ovarian cancer who had debulking surgery from 1996 through 2000. All patients underwent an en bloc resection of ovarian cancer and a rectosigmoid resection followed by an end-to-end anastomosis. Parameters for safety and efficacy were considered as primary statistical endpoints for the aim of this analysis. Results. Postoperative residual tumour was nil, 1 cm in 14, 34, and 14 patients, respectively. The median postoperative hospital stay was 11 days (range, 6 to 50 days). Intraoperative complications included an injury to the urinary bladder in one patient. Postoperative complications included wound complications (n=14, 21.5%), septicemia (n=9, 13.8%), cardiac complications (n=7, 10.8%), thromboembolic complications (n=5, 7.7%) ileus (n=2, 3.1%) anastomotic leak (n=2, 3.1%) and fistula (n=1, 1.5%). Reasons for a reoperation during the same admission included repair of an anastomotic leak (n=1), postoperative hemorrhage (n=1), and wound debridement (n=1). Wound complications, septicemia, and anastomotic leak formation were more frequent in patients who had a serum albumin level of less than or equal to 30 g/L preoperatively. There was one surgically related mortality in a patient who died from a cerebral vascular accident 2 days postoperatively. Conclusions. An en bloc resection as part of primary cytoreductive surgery for ovarian cancer is effective and its morbidity is acceptably low. (C) 2001 Academic Press.

Peritoneal cytology: impact on disease-free survival in clinical stage I endometrioid adenocarcinoma of the uterus

The prognostic significance of positive peritoneal cytology in endometrial carcinoma has led to the incorporation of peritoneal cytology into the current FIGO staging system, While cytology was shown to be prognostically relevant in patients with stage II and III disease, conflicting data exists about its significance in patients who would have been stage I but were classified as stage III solely and exclusively on the basis of positive peritoneal cytology (clinical stage I). Analysis was based on the data of 369 consecutive patients with clinical stage I endometrioid adenocarcinoma of the endometrium. Standard treatment consisted of an abdominal total hysterectomy, bilateral salpingo-oophorectomy with or without pelvic lymph node dissection. Peritoneal cytology was obtained at laparotomy by peritoneal washing of the pouch of Douglas and was considered positive if malignant cells could be detected regardless of the number of malignant cells present. Disease-free survival (DFS) was considered the primary statistical endpoint. In 13/369 (3.5%) patients, positive peritoneal cytology was found. The median follow-up was 29 months and 15 recurrences occurred. Peritoneal cytology was independent of the depth of myometrial invasion and the grade of tumour differentiation, Patients with negative washings had a DFS of 96'7e at 36 months compared with 67% for patients with positive washings (log-rank P < 0.001). The presence of positive peritoneal cytology in patients with clinically stage I endometrioid adenocarcinoma of the endometrium is considered an adverse prognostic factor. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.

The progesterone receptor exon 4 Va1660Leu G/T polymorphism and risk of breast cancer in Australian women

An Alu insertion polymorphism of the progesterone receptor (PR) was reported recently to be associated with a reduced risk of breast cancer, with risks of 0.8- and 0.3-fold associated with the heterozygote and homozygote genotypes, respectively. This intronic variant is considered to be in linkage disequilibrium with an exon 4 hinge region G to T Val660Leu polymorphism. We investigated whether the exon 4 PR polymorphism was associated with breast cancer in Australian women, using a population-based study of 1452 cases and 793 controls, half of whom were

The BRCA2 372 HH genotype is associated with risk of breast cancer in Australian women under age 60 years

The BRCA2 N372H nonconservative amino acid substitution polymorphism appears to affect fetal survival in a sex-dependent manner, and the HH genotype was found to be associated with a 1.3-fold risk of breast cancer from pooling five case-control studies of Northern European women. We investigated whether the BR 2 N372H polymorphism was associated with breast cancer in Australian women using a population-based case-control design. The BRCA2 372 genotype was determined in 1397 cases under the age of 60 years at diagnosis of a first primary breast cancer and in 775 population-sampled controls frequency matched for age. Case-control analyses and comparisons of genotype distributions were conducted using logistic regression. All of the statistical tests were two-tailed. The HH genotype was independent of age and family history of breast cancer within cases and controls, and was more common in cases (9.2% versus 6.5%). It was associated with an increased risk of breast cancer, 1.47-fold unadjusted (95% confidence interval, 1.05-2.07; P = 0.02), and 1.42-fold (95% confidence interval, 1.00-2.02; P = 0.05) after adjusting for measured risk factors. This effect was still evident after excluding women with any non-Caucasian ancestry or the 33 cases known to have inherited a mutation in BRCA1 or BRCA2, and would explain similar to3% of breast cancer. The BRCA2 N372H polymorphism appears to be associated with a modest recessively inherited risk of breast cancer in Australian women. This result is consistent with the findings for Northern European women.

Nuclear PTEN expression and clinicopathologic features in a population-based series of primary cutaneous melanoma

Germline mutations of the PTEN tumor-suppressor gene, on 10q23, cause Cowden syndrome, an inherited hamartoma syndrome with a high risk of breast, thyroid and endometrial carcinomas and, some suggest, melanoma. To date, most studies which strongly implicate PTEN in the etiology of sporadic melanomas have depended on cell lines, short-term tumor cultures and noncultured metastatic melanomas. The only study which reports PTEN protein expression in melanoma focuses on cytoplasmic expression, mainly in metastatic samples. To determine how PTEN contributes to the etiology or the progression of primary cutaneous melanoma, we examined cytoplasmic and nuclear PTEN expression against clinical and pathologic features in a population-based sample of 150 individuals with incident primary cutaneous melanoma. Among 92 evaluable samples, 30 had no or decreased cytoplasmic PTEN protein expression and the remaining 62 had normal PTEN expression. In contrast, 84 tumors had no or decreased nuclear expression and 8 had normal nuclear PTEN expression. None of the clinical features studied, such as Clark's level and Breslow thickness or sun exposure, were associated with cytoplasmic PTEN expressional levels. An association with loss of nuclear PTEN expression was indicated for anatomical site (p = 0.06) and mitotic index (p = 0.02). There was also an association for melanomas to either not express nuclear PTEN or to express p53 alone, rather than both simultaneously (p = 0.02). In contrast with metastatic melanoma, where we have shown previously that almost two-thirds of tumors have some PTEN inactivation, only one-third of primary melanomas had PTEN silencing. This suggests that PTEN inactivation is a late event likely related to melanoma progression rather than initiation. Taken together with our previous observations in thyroid and islet cell tumors, our data suggest that nuclear-cytoplasmic partitioning of PTEN might also play a role in melanoma progression. (C) 2002 Wiley-Liss, Inc.