HIV-associated wasting prevalence in the era of modern antiretroviral therapy

OBJECTIVE

To understand the prevalence of HIV-associated wasting (HIVAW) in the United States.

DESIGN

Medical and pharmacy claims study using IBM MarketScan Commercial, Medicare Supplemental and Medicaid Databases.

METHODS

Study period: July 2012-September 2018 (first HIV diagnosis claim = HIV index date). People with HIV (PWH) were excluded if they were aged less than 18 years, had any malignancy claim or had less than 6 months of enrollment data pre or post-HIV index date. HIVAW was defined by proxy using claims for weight loss-related diagnoses, appetite stimulant/nontestosterone anabolic agents or enteral/parenteral nutrition. Prevalence was reported cumulatively, by insurance type and antiretroviral therapy (ART) pharmacy claims (defined as ≥1 pharmacy claim of any ART within 12 months post-HIV index date). Statistical analysis assessed factors potentially associated with HIVAW.

RESULTS

The study population comprised 42 587 PWH (64.6% male, mean age 44 years, 67.5% on Medicaid, 63.9% on ART). Cumulative HIVAW prevalence (2012-2018) was 18.3% (n = 7804) for all PWH (17.9% on ART, 19.1% not on ART). HIVAW prevalence by payer was 7.5% for Commercial and Medicare Supplemental and 23.5% for Medicaid. The strongest associations with the likelihood of meeting the definition of HIVAW were for individuals with Medicaid and hospitalization(s) post-HIV index date; race and ART status were not associated.

CONCLUSIONS

Findings suggest HIVAW remains prevalent in PWH. ART use was not found to be associated with HIVAW. HIVAW was highest among those with Medicaid coverage or any hospitalization(s). Further research is needed to better understand additional factors associated with and contributing to HIVAW.

The mechanism of action of docetaxel (Taxotere) in xenograft models is not limited to bcl-2 phosphorylation

Docetaxel is a new taxoid compound with a broad spectrum of antitumor activity. Previous studies have shown that in vitro treatment of specific human tumor lines with docetaxel is associated with the phosphorylation and inactivation of the bcl-2 protein and the occurrence of apoptosis. The goal of this study was to examine whether bcl-2 expression is truly required for in vivo responsiveness to docetaxel. The expression and state of phosphorylation of bcl-2 was examined in human MX-1 breast or DU-145 prostate tumors explanted from nu/nu mice treated with docetaxel. The MX-1 cells accumulated in the G2/M phase of the cell cycle and exhibited phosphorylation of bcl-2 after treatment with docetaxel. By Western blot analysis DU-145 prostate tumor cells did not express bcl-2 protein before or following in vivo treatment with docetaxel. However, docetaxel was highly active against the DU-145 tumor xenograft model. Thus, docetaxel induces apoptosis and cell death through a different, bcl-2-independent mechanism in the DU-145 human prostate tumor, indicating that bcl-2 may not have prognostic value for treatment with docetaxel.

Altered profiles in nuclear matrix proteins associated with DNA in situ during progression of breast cancer cells

Nuclear matrix proteins (NMPs) show promise as informative biomarkers in following the pathogenesis of breast cancer. The nuclear matrix is a dynamic RNA-protein network involved in the organization and expression of chromatin. Cisplatin, which preferentially cross-links nuclear matrix proteins to DNA in situ, may be used to identify NMPs that organize and/or regulate the processing of DNA. In this study, we analyzed the nuclear matrix proteins from an estrogen receptor-positive breast cancer cell line panel consisting of MCF-7, MIII, LCC1, and LCC2 cell lines. This cell line panel reflects the stages of malignant progression in breast cancer. Proteins isolated from nuclear matrices and proteins cross-linked to nuclear DNA in situ with cisplatin were analyzed by two-dimensional gel electrophoresis. Specific changes in nuclear matrix proteins bound to nuclear DNA were identified. In concordance with estrogen independence and antiestrogen insensitivity, a loss in cisplatin cross-linking of specific NMPs to nuclear DNA was observed. Our results suggest that progression of breast cancer is accompanied by a reorganization of chromosomal domains, which may lead to alterations in gene expression.

Nuclear matrix proteins associated with DNA in situ in hormone-dependent and hormone-independent human breast cancer cell lines

The nuclear matrix is a dynamic RNA-protein complex that organizes chromatin and regulates nuclear DNA metabolism. Nuclear matrix proteins informative in the diagnosis of cancer have been identified. Here, the nuclear matrix breast cancer proteins (NMBCs) cross-linked to nuclear DNA in situ with cisplatin in human breast cancer cell lines were analyzed by two-dimensional gel electrophoresis. We identified NMBCs that were differentially associated with nuclear DNA of hormone-dependent and -independent breast cancer cell lines. Three DNA cross-linked NMBCs were found to be exclusive to estrogen receptor-positive, hormone-dependent breast cancer cells, whereas two NMBCs were observed only in estrogen receptor-negative, hormone-independent breast cancer cells. Changes in these NMBCs were observed when hormone-dependent breast cancer cells became hormone independent. Furthermore, we show that the intermediate filament protein vimentin is associated with the nuclear DNA of MDA-MB-231 breast cancer cells, an estrogen receptor-negative, hormone-independent breast cancer cell line with high metastatic potential. These nuclear matrix DNA-binding proteins may play important roles in breast tumorigenesis.

Organization of chromatin in cancer cells: role of signalling pathways

The role of mechanical and chemical signalling pathways in the organization and function of chromatin is the subject of this review. The mechanical signalling pathway consists of the tissue matrix system that links together the three-dimensional skeletal networks, the extracellular matrix, cytoskeleton, and nuclear matrix. Intermediate filament proteins are associated with nuclear DNA, suggesting that intermediate filaments may have a role in the organization of chromatin. In human hormone-dependent breast cancer cells, the interaction between cytokeratins and chromatin is regulated by estrogens. Transcription factors, histone acetyltransferases, and histone deacetylases, which are associated with the nuclear matrix, are components of the mechanical signalling pathway. Recently, we reported that nuclear matrix-bound human and chicken histone deacetylase 1 is associated with nuclear DNA in situ, suggesting that histone deacetylase has a role in the organization of nuclear DNA. Chemical signalling pathways such as the Ras/mitogen-activated protein kinase (Ras/MAPK) pathway stimulate the activity of kinases that modify transcription factors, nonhistone chromosomal proteins, and histones. The levels of phosphorylated histones are increased in mouse fibroblasts transformed with oncogenes, the products of which stimulate the Ras/MAPK pathway. Histone phosphorylation may lead to decondensation of chromatin, resulting in aberrant gene expression.

Organization of chromatin in cancer cells: role of signalling pathways

The role of mechanical and chemical signalling pathways in the organization and function of chromatin is the subject of this review. The mechanical signalling pathway consists of the tissue matrix system that links together the three-dimensional skeletal networks, the extracellular matrix, cytoskeleton, and nuclear matrix. Intermediate filament proteins are associated with nuclear DNA, suggesting that intermediate filaments may have a role in the organization of chromatin. In human hormone-dependent breast cancer cells, the interaction between cytokeratins and chromatin is regulated by estrogens. Transcription factors, histone acetyltransferases, and histone deacetylases, which are associated with the nuclear matrix, are components of the mechanical signalling pathway. Recently, we reported that nuclear matrix-bound human and chicken histone deacetylase 1 is associated with nuclear DNA in situ, suggesting that histone deacetylase has a role in the organization of nuclear DNA. Chemical signalling pathways such as the Ras/mitogen-activated protein kinase (Ras/MAPK) pathway stimulate the activity of kinases that modify transcription factors, nonhistone chromosomal proteins, and histones. The levels of phosphorylated histones are increased in mouse fibroblasts transformed with oncogenes, the products of which stimulate the Ras/MAPK pathway. Histone phosphorylation may lead to decondensation of chromatin, resulting in aberrant gene expression.Key words: histone acetylation, histone phosphorylation, nuclear matrix, cytoskeleton, histone deacetylase, cancer.

Estrogen regulates the association of intermediate filament proteins with nuclear DNA in human breast cancer cells

In a previous study we showed that the levels of the intermediate filament proteins, cytokeratins 8, 18, and 19, in the nuclear matrix-intermediate filament (NM-IF) fraction from the hormone-dependent and estrogen receptor (ER)-positive human breast cancer cell line T-47D5 were regulated by estrogens. In contrast, estrogens did not regulate the cytokeratins in the NM-IF fraction of the hormone-independent and ER-positive cell line, T5-PRF. In this study, human breast cancer cells were treated with cis-diamminedichloroplatinum to cross-link protein to nuclear DNA in situ, and proteins bound to DNA were isolated. We show that cytokeratins 8, 18, and 19 of T-47D5 and T5-PRF were associated with nuclear DNA in situ. The levels of the cytokeratins 8, 18, and 19 bound to nuclear DNA or associated with the cytoskeleton of T-47D5 human breast cancer cells decreased when estrogens were depleted or the pure antiestrogen ICI 164,384 was added. In contrast, the cytokeratin levels associated with nuclear DNA or cytoskeleton were not significantly affected by estrogen withdrawal or antiestrogen administration in T5-PRF cells. These observations suggest that estrogen regulates the organization of nuclear DNA by rearrangement of the cytokeratin filament network in hormone-dependent, ER-positive human breast cancer cells and that this regulation is lost in hormone-independent, ER-positive breast cancer cells.

Chromatin, nuclear matrix and the cytoskeleton: role of cell structure in neoplastic transformation (review)

Aberrant nuclear and cellular structures are hallmarks of malignant transformation. Thus it is not surprising that the three-dimensional structure of the cell both affects and is affected by changes in gene expression. Here we review the role of the cytoskeleton, nuclear matrix, and chromatin structure in the genesis of cancer. The shape of a cell is governed by a dynamic tissue matrix, which includes extracellular matrix, cytoskeleton and nuclear matrix. Mechanical and chemical signals are transmitted to the nucleus, resulting in alterations in the three-dimensional chromatin organization of genes. The signal transduction pathways affect histone modifications, such as acetylation and phosphorylation, resulting in a relaxed chromatin structure observed in oncogene-transformed cells.

In situ cross-linking by cisplatin of nuclear matrix-bound transcription factors to nuclear DNA of human breast cancer cells

Cisplatin is an antitumor drug that is used to treat several types of cancers. In this study, we analyzed the proteins that were cross-linked to DNA in situ in MCF-7 human breast cancer cells incubated with cisplatin. We show that cisplatin cross-links nuclear matrix proteins to DNA. In immunoblotting experiments, we found that nuclear matrix-associated transcription factors and cofactors (estrogen receptor, HET/SAF-B, hnRNP K, and histone deacetylase 1) were cross-linked to nuclear DNA. These transcription factors and cofactors have essential roles in the regulation of genes involved in the proliferation of breast cancer cells and in the organization and structure of chromatin. We applied a novel protocol to demonstrate that the nuclear matrix-bound transcription factors/cofactors were cross-linked to DNA fragments attached to the nuclear matrix. These results suggest that the cross-linking of nuclear matrix-associated transcription factors and cofactors to DNA may be one of the mechanisms by which cisplatin inhibits transcription and replication processes.

Novel nuclear matrix protein HET binds to and influences activity of the HSP27 promoter in human breast cancer cells

Since the small heat shock protein hsp27 enhances both growth and drug resistance in breast cancer cells, and is a bad prognostic factor in certain subsets of breast cancer patients, we have characterized the transcriptional regulation of hsp27, with the long-term goal of targeting its expression clinically. The majority of the promoter activity resides in the most proximal 200 bp. This region contains an imperfect estrogen response element (ERE) that is separated by a 13-bp spacer that contains a TATA box. Gel-shift analysis revealed the binding of a protein (termed HET for Hsp27-ERE-TATA-binding protein) to this region that was neither the estrogen receptor nor TATA-binding protein. We cloned a complete cDNA (2.9 kb) for HET from an MCF-7 cDNA library. To confirm the identity of the HET clone, we expressed a partial HET clone as a glutathione S-transferase fusion protein, and showed binding to the hsp27 promoter fragment in gel-retardation assays. The HET clone is almost identical to a recently published scaffold attachment factor (SAF-B) cloned from a HeLa cell cDNA library. Scaffold attachment factors are a subset of nuclear matrix proteins (NMP) that interact with matrix attachment regions. Analyzing how HET could act as a regulator of hsp27 transcription and as a SAF/NMP, we studied its subnuclear localization and its effect on hsp27 transcription in human breast cancer cells. We were able to show that HET is localized in the nuclear matrix in various breast cancer cell lines. Furthermore, in transient transfection assays using hsp27 promoter-luciferase reporter constructs, HET overexpression resulted in a dose-dependent decrease of hsp27 promoter activity in several cell lines.

Nuclear matrix proteins in well and poorly differentiated human breast cancer cell lines

The nuclear matrix, besides providing the structural support of the nucleus, is involved in various cellular functions of the nucleus. Nuclear matrix proteins (NMPs), which are both tissue- and cell type-specific, are altered with transformation and state of differentiation. Furthermore, NMPs have been identified as informative markers of disease states. Here, the NMP profiles from human breast cancer cell lines and breast tumours were analyzed using two-dimension gel electrophoresis. We identified NMPs that are associated with well and poorly differentiated human breast cancer cells in vitro and in vivo. Five NMPs (NMBC 1-5) were found to be exclusive for well-differentiated human breast cancer cells, while one NMP (NMBC-6) was found to be present only in poorly differentiated human breast cancer cells. The identification of these proteins suggests the potential use of nuclear matrix proteins as prognostic indicators.

Altered nuclear matrix protein profiles in oncogene-transformed mouse fibroblasts exhibiting high metastatic potential

The nuclear matrix provides the structural support of the nucleus and is involved in various cellular functions of the nucleus. Nuclear matrix proteins, which are both tissue and cell type specific, are altered with transformation and state of differentiation. Here, nuclear matrix protein profiles of oncogene-transformed mouse fibroblasts with various degrees of metastatic activity were analyzed using two-dimensional gel electrophoresis. This study shows that as the metastatic potential increases, similar nuclear matrix protein profiles are associated with each increase regardless of transformation agent.

TGF-beta 1 stimulation of cell locomotion utilizes the hyaluronan receptor RHAMM and hyaluronan

TGF-beta is a potent stimulator of motility in a variety of cell types. It has recently been shown that hyaluronan (HA) can directly promote locomotion of cells through interaction with the HA receptor RHAMM. We have investigated the role of RHAMM and HA in TGF-beta-stimulated locomotion and show that TGF-beta triggers the transcription, synthesis and membrane expression of the RHAMM receptor and the secretion of HA coincident with the induction of the locomotory response. This was demonstrated by both incubating cells with exogenous TGF-beta 1 and by stimulating the production of bioactive TGF-beta 1 in tumor cells transfected with TGF-beta 1 under the control of the metallothionein promoter. TGF-beta 1-induced locomotion was suppressed by antibodies that prevented HA/RHAMM interaction, using polyclonal antibodies to either RHAMM fusion protein or RHAMM peptides, or mAbs to purified RHAMM. Peptides corresponding to the HA-binding motif of RHAMM also suppressed TGF-beta 1-induced increases in motility rate. Spontaneous locomotion of fibrosarcoma cells was blocked by neutralizing secreted TGF-beta with panspecific TGF-beta antibodies and by inhibition of TGF-beta 1 secretion with antisense oligonucleotides. Polyclonal anti-RHAMM fusion protein antibodies and peptide from the RHAMM HA-binding motif also suppressed the spontaneous motility rate of fibrosarcoma cells. These data suggest that fibrosarcoma cell locomotion requires TGF-beta, and the pathway by which TGF-beta stimulates locomotion uses the HA receptor RHAMM and HA.

Autocrine induction of tumor protease production and invasion by a metallothionein-regulated TGF-beta 1 (Ser223, 225)

An expression vector was constructed in which TGF-beta 1 was placed under the control of the metallothionein promoter. Cys223 and Cys225 in the TGF-beta 1 propeptide were converted to serines, mutations which result in dissociation of the pro-peptide and secretion of bioactive TGF-beta 1 [Brunner, A.M., Marquardt, H., Malacko, A.R., Lioubin, M.N. and Purchio, A.F. (1989) J. Biol. Chem., 264, 13660-13664]. A fibrosarcoma was transfected with this plasmid and a clone (17.18) was selected in which TGF-beta 1 mRNA was able to be induced six-fold following zinc sulphate treatment. These cells increased the secretion of bioactive TGF-beta 1 14-fold and exhibited a coincidental increase in jun-B mRNA expression, suggesting that secreted TGF-beta 1 was acting to induce this early response gene by autocrine activation. Following zinc sulphate induction, the tumor cells became progressively more motile and able to invade collagen gels. In contrast to parental tumor not bearing the TGF-beta 1 expression vector, zinc sulphate stimulation of clone 17.18 enhanced collagenase IV and procathepsin L mRNA levels and enhanced the secretion of many collagenolytic proteases into the medium. Since the action of TGF-beta generally decreases proteolysis by suppression of protease transcription, we compared the response of normal parental fibroblasts to ras-transformed fibrosarcomas and confirmed that TGF-beta could greatly enhance collagenase IV and procathepsin L mRNA levels while having little effect on non-transformed fibroblasts. These experiments indicate that induction of TGF-beta secretion can enhance motility and protease production through autocrine activation, thus increasing the invasion potential of fibrosarcomas.

Early induction of ribonucleotide reductase gene expression by transforming growth factor beta 1 in malignant H-ras transformed cell lines

Previous investigations have indicated that the suppression of proliferation by transforming growth factor (TGF) beta 1 is often lost upon cellular transformation, and that proliferation of some tumors is stimulated by TGF-beta. The present study provides the first observation of a link between TGF-beta 1 regulation of this process and alterations in the expression of ribonucleotide reductase, a highly controlled rate-limiting step in DNA synthesis. A series of radiation and T24-H-ras-transformed mouse 10T1/2 cell lines exhibiting increasing malignant potential was evaluated for TGF-beta 1 induced alterations in ribonucleotide reductase M1 and M2 gene expression. Early increases in M1 and/or M2 message and protein levels were observed only in malignant cell lines. The TGF-beta 1 induced changes in M1 and/or M2 gene expression occurred prior to any detectable changes in the rates of DNA synthesis, supporting the novel concept that ribonucleotide reductase gene expression can be elevated by TGF-beta 1 without altering the proportion of cells in S phase. T24-H-ras-transformed 10T1/2 cells were transfected with a plasmid containing the coding region of TGF-beta 1 under the control of a zinc-sensitive metallothionein promoter. When these cells were cultured in the presence of zinc, a large induction of TGF-beta 1 message was observed within 1 h. Both M1 and M2 genes were also induced, with increased mRNA levels appearing 2 h after zinc treatment, or 1 h after TGF-beta 1 message levels were clearly elevated. In total, the data suggests a mechanism of autocrine stimulation of malignant cells by TGF-beta 1, in which early alterations in the regulation of ribonucleotide reductase may play an important role.