Altered metastatic behavior of human breast cancer cells after experimental manipulation of matrix metalloproteinase 8 gene expression

Previous work in our laboratory led to the cloning, from the same parent tumor cell line (MDA-MB-435), of two human breast cancer cell lines (M-4A4 and NM-2C5) with opposite metastatic phenotypes. Additional investigations revealed that the nonmetastatic cell line NM-2C5 overexpressed the neutrophil collagenase, matrix metalloproteinase (MMP)-8, relative to its partner. Because other studies have implicated the MMP family in promoting tumor metastasis, we investigated the apparently paradoxical expression of MMP-8 in these cell lines. By genetic engineering, we inverted its relative levels of expression in the two partners and studied the effects on the behavior of the tumors that they generated in athymic mice. Knock-down of expression in NM-2C5 cells by transduction with a sequence encoding a specific ribozyme and overexpression of MMP-8 in M-4A4 cells by retroviral transduction both strikingly changed metastatic performance in opposite directions, indicating that this gene plays a role in the regulation of tumor metastasis.     

Gene expression profiling of human lymph node metastases and matched primary breast carcinomas: Clinical implications

The genetic program that drives tumor metastasis and the mode and timing of its initiation are of great practical significance to clinical management. Modern technical advances open new opportunities for gaining useful relevant information. Gene expression profiles of histologically‐verified viable tissue from lymph node metastases were compared with those of matched primary breast cancers from 10 different patients, among samples from over 400 cases, using high‐throughput oligonucleotide arrays comprising probes for 22,000 genes. It was observed that metastases have very similar expression signatures to their parent tumors. However, detailed computational analysis revealed that a small number of genes were consistently differentially expressed between 100% of tumors and metastases, suggesting that these are mechanistically important. Lists of such candidate genes, of potential clinical interest, are provided. We interpret these results in the framework of a meta‐analysis of previous investigations by others and ourselves and of existing clinical knowledge on the behavior of human tumors. The collective data show that metastases resemble their primary tumors but the signatures obtained in different studies are not sufficiently reproducible or informative to be prognostically useful, although they do give valuable insights into the pathogenesis and biology of human tumor metastasis. The findings indicate that the genetic program encoding metastasis is implemented progressively over time although, occasionally, this evolution can occur rapidly, early in the life of the neoplasm. The important clinical significance of this deduction is that, in most patients, early detection provides time for appropriate therapeutic intervention to be effective in obstructing metastasis.     

Formulation and in vitro investigation of antibacterial vaginal suppositories. Part 2. In vitro membrane diffusion and microbiologic studies]

After the physical parameters had been determined, the in vitro drug liberation from vaginal suppositories containing 100 mg of antibacterial agent (sulphadimine, chloramphenicol, gentamicin-sulphate) was studied by membrane diffusion and microbiological methods. Among the vehicles available in Hungary the hydrophylic Massa macrogoli was found to be the best for this purpose. Among the lipophilic bases the in vitro drug liberation of the French Suppocire NA product was significantly better (p < 0.05) compared to the other lipophilic bases. This vehicle is recommended by the authors for the topical treatment of vaginitis, as these suppositories have the further advantage that they can easily be produced on a magistral, galenical or industrial scale as well. In the first part of the publication the formulation and some important physical parameters of lipophilic and hydrophilic antibacterial suppositories for vaginal use were described. In the present paper the drug liberation ability of the compositions with proper physical parameters was studied. The published results were obtained from measurements performed 1 week after formulation.     

Biological and clinical studies relevant to metastasis of breast cancer

The progression of neoplastic epithelial proliferation in the breast does not inevitably lead to an infiltrating carcinoma. The carcinoma-in-situ which do metastasize apparently produce cells whose first moves through tissue are facilitated by lysing inert intercellular material (types I and IV collagen). Metastasis, defined as the capability of tumor cells to disseminate to distant sites in the body and set up secondary neoplasms, is a propeny separate and additional to tumorigenicity or local invasiveness. The driving engine of the metastatic process is identified as regulatory genomic disturbances in the population of cells within the tumor. Success or failure of secondary tumor growth in distant sites depends upon the outcome of interaction with local microenvironmental factors and systemic endocrine and immunological conditions.     

Effects of altering surface glycoprotein composition on metastatic colonisation potential of murine mammary tumour cells

This study has examined cells from naturally-occurring murine mammary tumours to ascertain whether cell surface glycoproteins play a significant role in colonisation of the lungs after intravenous inoculation. It was found that gel electrophoretic analysis of membrane extracts and lectin adsorption studies did not reveal any consistent differences in glycoprotein composition of cells from tumours which can heavily colonise the lungs relative to ones from tumours which cannot do so or to cells from pulmonary metastases. Also, alteration of structural and functional properties of surface glycoproteins by treatment with succinylated lectins or with drugs such as tunicamycin and swainsonine, which inhibit glycosylation of membrane proteins, had no specific effects on metastatic colonisation of the lungs. Tunicamycin apparently decreased capability to form experimental metastases but also diminished tumourigenicity on subcutaneous inoculation, although it did not affect tumour cell viability in vitro. This information supports earlier studies from this laboratory involving enzymic digestion of the surface of living tumour cells before inoculation and demonstrates that the pulmonary colonisation capability of these mammary tumour cells can withstand global disorganisation of membrane glycoprotein structure and composition. This implies that either the surface glycoproteins are not important in the colonisation process, or that these tumour cells have great capability for rapid repair of their surfaces. It is concluded that a clear answer to whether surface glycoprotein composition has a decisive role in pulmonary colonisation by these mammary tumour cells requires introduction of stable heritable traits into tumour cell populations by genetic manipulation.     

Long-term fate of heterotopic liver transplants in rats with portal vein inflow only

Previous studies have suggested that hepatic arterial flow in heterotopic partial liver transplants is necessary to ensure graft survival and regenerative capacity. This report presents findings in a syngeneic rat strain (Lewis) that partial liver transplants can be successfully heterotopically transplanted in the long term with the only inflow coming from the portal vein. When the host liver undergoes a nearly complete resection at 3-4 weeks, the transplanted liver regenerates to maintain the health of the host. Moderate to massive hepatocellular necrosis occurs in the first 3 months postoperatively, with recovery by 4-5 months. Liver transplants 8-10 months postoperatively appear architecturally normal. No host liver tissues were found to be regenerating after subtotal host liver resection. We conclude that portal vein reconstruction without hepatic arterial inflow can sustain a partial liver transplant in the long term, replacing the function of the host liver.     

Clinical experience with preimplantation diagnosis of sex by dual fluorescent in situ hybridization

Purpose Our purpose was to assess the clinical application of dual fluorescent in situhybridization (FISH) for the diagnosis of sex in the human preimplantation embryo. Results Over a 2-year period, 18 couples at risk of transmitting X-linked recessive disorders underwent preimplantation diagnosis of embryo sex by dual FISH with X and Y chromosome-specific DNA probes. A total of 27 in vitro fertilization (IVF) treatment cycles led to nine pregnancies; 7 reached the stage of clinical recognition, of which 2 spontaneously aborted. There were five live births, three singleton and two twin: none in disagreement with the diagnosed sex. The diagnosis was corroborated in 51 of the 74 nontransferred embryos. The efficiency of the procedure improved throughout the four treatment cycles. This was reflected in the increased proportion of double embryo transfers (from 50% in series 1 and 2 to 100% in series 3 and 4), with a consequent improvement in pregnancy rate (from 28 to 71% per embryo transfer). The excess of male embryos (male∶female, 60∶40 overall) and the high proportion of biopsied embryos with abnormal numbers of X and Y chromosome signals (14.5%) effectively reduced the number of normal female embryos available for transfer. Conclusion Dual FISH is an efficient technique for determination of the sex of human preimplantation embryos and the additional ability to detect abnormal chromosome copy numbers, which is not possible via the polymerase chain reaction, (PCR), makes FISH the preferred technique.