Circulating Ki67 positive lymphocytes in multiple myeloma and benign monoclonal gammopathy.

AIMS--To estimate the proportion and nature of the proliferating (Ki67+) circulating lymphocytes in a series of patients with multiple myeloma and monoclonal gammopathy of unknown significance (MGUS) and to correlate this with other clinical and laboratory parameters, using blood from healthy adults as a control. To investigate the extent to which the B and T lymphoid components are involved in progression and/or control of disease. METHODS--Blood lymphocytes from 15 patients with multiple myeloma, 10 patients with MGUS and 10 healthy adults were analysed using a sequential double immunoenzymatic staining technique. Antibodies directed against Ki67 were used to detect cells in cycle, CD3, CD4, and CD8 to identify T cells, HLA-Dr as a marker for B cells and activated T cells, and CD11b as a marker for natural killer cells. Polyclonal antibodies directed against the kappa and lambda immunoglobulin light chains were also used to detect B cells. RESULTS--The proportion of proliferating (Ki67+) lymphocytes was significantly higher in patients with multiple myeloma (6.8 +/- 2.6) and MGUS (3.5 +/- 1.1) compared with the normal controls (1.69 +/- 0.3); this was also true when multiple myeloma and MGUS cases were compared. In multiple myeloma and MGUS over 50% of the Ki67+ cells were activated T lymphocytes (CD3+/HLA-Dr+); a minority (11%) were non-clonal B lymphocytes. In contrast to controls (6.7 +/- 1.9), in patients with multiple myeloma and MGUS the proportion of proliferating T cells expressing CD8 (23.6 +/- 12.5 and 15.3 +/- 7.7, respectively) and CD11b (13 +/- 8.7 and 11.6 +/- 3.9, respectively) was higher. In multiple myeloma there was a positive correlation between the proportion of Ki67+ lymphocytes, beta-2-microglobulin concentrations and disease stage. CONCLUSIONS--Although the number of patients investigated is small, this study suggests that Ki67 expression in blood lymphocytes from patients with multiple myeloma may be a good prognostic indicator for aggressive disease and may help to distinguish multiple myeloma from MGUS. The activated proliferating T cells in these diseases may represent an immunological reaction against the tumour.     

Implantation: The use of gonadotrophin-releasing hormone analogues in women receiving oocyte donation does not affect implantation rates

There is conflicting clinical evidence suggesting a positiverole for gonadotrophin-releasing hormone analogues (GnRHa) onimplantation in humans. This potential effect was evaluatedin this study taking the oocyte donation programme as a model.Patients were randomly allocated into one of the two treatmentgroups: group I received simultaneous treatment with GnRHa andsteroids, and group II only received exogenous steroid replacement.An analysis of the donors and semen quality showed similaritybetween recipient groups. There was no significant differencebetween groups in the number and quality of embryos replaced,clinical pregnancy and implantation rates. In summary, usinga model in which the endometrium can be analysed independentlyof the embryos, the results suggest that GnRHa are neither effectivenor detrimental for embryo implantation in humans.     

Effect of pre-operative blood transfusion on tumour metastases

The effects of allogenic blood transfusion on the subcutaneous growth and metastatic spread of two types of mouse tumour (B16 melanoma syngeneic to the C57/BL6 mouse and UV-2237 fibrosarcoma syngeneic to the C3H/He mouse) were studied. The growth rates of the primary tumour were not altered by transfusing the animals with allogeneic blood 14 days before tumour inoculation, but spontaneous metastasis from tumours formed at the inoculation site was augmented and accelerated for both tumour types. This effect was dependent on the strain of the blood donor, metastases of B16 melanoma being augmented by transfusion with blood from Balb/c animals, and UV-2237 fibrosarcoma by transfusion with C57/BL6 blood, but not by blood from other donor strains tested.     

Further electron microscopic studies on the mechanism of carcinogenesis: the specificity of the changes in carcinogen-treated mouse skin

This work was undertaken to determine if the ultrastructural changes seen in mouse skin carcinogenesis (Tarin, 1967a) are specific to the carcinogenic process. Electron microscopic examination of skin treated with non-carcinogenic irritant chemicals (benzene, turpentine) showed that the dermo-epidermal junction remained intact. The changes seen in this region in methylcholanthrene-treated skin were not present. The irritants did, however, produce changes in the epidermis and dermis but these differed from those seen in carcinogen-treated skin. The epidermis underwent regular hyperplasia and there was an increase in the number of inflammatory cells in the dermis. Dermal collagen fibre structure and arrangement were not altered. It is concluded that the changes seen at the dermo-epidermal junction in carcinogen-treated skin are directly related to the carcinogenic process and are not the result of non-specific irritation. The nature of the carcinogenic process is considered and disturbance of interaction between epithelium and connective tissue is offered as an explanation for the behaviour of neoplastic tissue. This hypothesis is discussed in the context of modern work which has shown that such interactions are of importance in the development and maintenance of normal tissue architecture.     

PTEN expression is maintained in sporadic colorectal tumours.

Loss of PTEN (phosphatase and tensin homologue deleted from chromosome 10) function has been implicated in the progression of several types of cancer. Allele loss close to the PTEN locus occurs in sporadic colon cancer and germline PTEN mutations cause Cowden disease, an inherited cancer syndrome characterized by an increased incidence of gastrointestinal tract lesions that can progress to colorectal carcinoma. However, although PTEN is a good candidate for involvement in the pathogenesis of sporadic colon cancer, previous analyses have not revealed a high frequency of somatic mutations in colorectal tumours. Alternative mechanisms which could lead to a loss of PTEN expression in colon cancer have not been investigated. This study monitored PTEN mRNA and protein levels in a panel of 50 tumour tissues obtained from 35 patients with sporadic colon cancer. RT-PCR and immunohistochemistry were used to evaluate the expression of mRNA and protein, respectively, in normal, adenoma and adenocarcinoma colorectal tissues as well as in metastatic lesions. To overcome the problem of heterogeneity and normal stromal cell contamination in homogenized tissue specimens, specific cell types were isolated by microdissection prior to PCR analysis. No loss of PTEN expression was evident in any of the colon tissues examined. PTEN protein was localized exclusively in the cytoplasm of normal and tumour cells and no correlation of immunostaining intensity and tumour stage or grade was revealed. As with previous deletion and mutation analyses, the present study suggests that loss of PTEN expression is not prevalent in sporadic colon cancer.     

Osteopontin gene expression determines spontaneous metastatic performance of orthotopic human breast cancer xenografts

A major problem in the therapeutic management of cancer is the growth of metastases in distant organs, but the genes orchestrating the process need to be identified for the rational design of new treatment. Here, we provide decisive experimental evidence demonstrating the causal involvement of a specific gene, osteopontin (OPN), in the pathogenesis of metastasis by human breast cancer cells and implicating some of its probable partners. Stable long-term depletion, or up-regulation, of OPN gene expression in a matched, isogenic pair of human breast cancer cell lines of differing metastatic proficiency reproducibly changed their ability to colonize distant organs. OPN down-regulation was achieved by transduction of the metastatic line with a DNA construct encoding a small hairpin RNA in a vector labeled with red fluorescent protein and resulted in a marked reduction of metastatic load (P < 0.01). Up-regulation of OPN in the negligibly metastatic line, with a green fluorescent protein-marked retroviral vector containing OPN cDNA driven by a strong promoter, resulted in heavy colonization of the lungs and lymph nodes (P < 0.005). The reciprocal changes in behavior of these matched cell lines cross-corroborate each other. Concomitant changes were seen in the expression of other metastasis-related genes in both modulated lines. The data indicate that therapeutic targeting of tumor OPN molecules could reset metastatically relevant gene networks, resulting in clinical benefit.     

Allelic imbalance and microsatellite instability in chromosomes 2p, 3p, 5q, and 18q in esophageal squamous carcinoma in patients from South Africa.

Microsatellite polymerase chain reaction (PCR) and fluorescent DNA technology was used to assess allelic imbalance (AI) or loss of heterozygosity (LOH) and microsatellite instability (MSI) in chromosomes 2p, 3p, 5q, and 18q in esophagectomy specimens from 39 patients who had squamous carcinoma and who lived in a high-incidence geographic location in South Africa. The squamous carcinomas were graded by conventional light microscopy and staged using the tumor-node-metastasis (TNM)-Union Internationale Contre Le Cancer (UICC) criteria. The DNA was isolated using proteinase K digestion and standard phenol-chloroform extraction procedure. Microsatellite PCR was performed using fluorescent, CY5-labeled primers for the following markers: D2S123 (2p), D3S659 (3p), D3S1255 (3p), D5S346 (5q), DCC (18q), D18S34 (18q), and D18S58 (18q). These markers were chosen because they are the most frequently used and most informative markers for these particular gene loci. Results were analyzed using software attached to an automated DNA sequencer. Molecular changes obtained were correlated with clinicopathologic parameters. Molecular analysis did not correlate with clinicopathologic features, such as tumor grade, stage, or lymph node status. No correlation with patient outcome was seen, though only limited follow-ups were obtained. Rates of MSI and LOH on 3p and 18q in these specimens are similar to the range seen in studies from other geographic areas. However, a striking point of departure is the high LOH (30% of informative cases) seen on 2p.