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C Biswas

Publications and source records attributed to C Biswas.

At least 37 records · Page 2Linked to original sources
PubMed1993

Tumor cell-derived collagenase-stimulatory factor increases expression of interstitial collagenase, stromelysin, and 72-kDa gelatinase.

The tumor cell-derived collagenase-stimulatory factor (TCSF) was previously purified from human lung carcinoma cells (S. M. Ellis, K. Nabeshima, and C. Biswas, Cancer Res., 49: 3385-3391, 1989). This protein is present on the surface of several types of human tumor cells in vitro and in vivo and stimulates production of interstitial collagenase in human fibroblasts. In this study it is shown that TCSF stimulates expression in human fibroblasts of mRNA for stromelysin 1 and 72-kDa gelatinase/type IV collagenase, as well as for interstitial collagenase. Measurement of enzyme protein by immunoassay showed that the amounts of interstitial collagenase and stromelysin 1 were increased in TCSF-treated fibroblasts; gelatin zymography indicated that there was an increase in the 72-kDa gelatinase. These results indicate that tumor cell interaction with fibroblasts via TCSF could lead to increased degradation of interstitial or basement membrane matrix components and thus to enhanced tumor cell invasion.

Animals↗
PubMed1993

Activation by protein synthesis inhibitors of glucose transport into L6 muscle cells.

The effects of protein synthesis inhibitors on glucose transport into L6 myotubes was examined. Similar to the acute effects of insulin, short-term treatment with anisomycin or cycloheximide increased transport 2-fold. Kinetic studies demonstrated that this activation was due to a doubling in the Vmax values. The effects of anisomycin or cycloheximide were not additive to that of insulin. Both protein synthesis inhibitors caused only small increases in GLUT4 expression and negligible effects on GLUT1 expression. Anisomycin, as well as insulin, induced the translocation of both transporters from intracellular vesicles to the plasma membrane through not in quantities sufficient to entirely account for the activation of transport. The results indicate that protein synthesis inhibitors stimulate hexose transport in L6 myotubes by increasing the number of transporters in the plasma membrane and augmenting the intrinsic catalytic activity of the transporters.

Animals↗
PubMed1991

Nucleotide sequence of a cDNA for the alpha subunit of human mitochondrial ATP synthase.

A full length cDNA clone of the alpha subunit of mitochondrial ATP synthase (EC 3.6.1.34) has been isolated from a cDNA library prepared from LX-1 human tumor cells in the lambda-Zap vector. The clone is 1883 base pairs (bp) in length and contains a 1659 bp open reading frame encoding a polypeptide of 553 residues. The deduced amino acid sequence is highly homologous to ATP synthase from several other species.

Amino Acid Sequence↗
PubMed1991

Partial sequencing and characterization of the tumor cell-derived collagenase stimulatory factor.

A tumor cell-derived, collagenase stimulatory factor (TCSF), previously isolated and purified from LX-1 human lung carcinoma cells and judged by immunoblotting and SDS-PAGE to contain a single protein of approximately 58 kDa, has been further analyzed for its biological activity and composition. Three significant new findings have been made. First, the biological activity of TCSF preparations was shown definitively to reside in the 58-kDa protein. This was achieved in two ways: (a) a polyclonal antibody was raised against the 58-kDa protein, after excision from an SDS-PAGE gel, and shown to inhibit the stimulation of fibroblast collagenase production by TCSF preparations; (b) the 58-kDa protein was eluted from a transblot of purified TCSF and shown to stimulate fibroblast collagenase production. Second, partial sequencing of the 58-kDa protein revealed no significant homologies with other known collagenase stimulatory factors. Third, purified TCSF was found, on transblotting to Immobilon, to contain a doublet of 58 kDa (TCSF1) and 54 kDa (TCSF2) proteins; the former was present in higher concentration than the latter. N-terminal amino acid sequencing of the two intact proteins and of four corresponding pairs of tryptic peptides derived from the two proteins showed identity in each case, indicating that TCSF1 and TCSF2 are very similar in composition. However, TCSF1 but not TCSF2 stimulated fibroblast collagenase production, confirming that the 58-kDa protein is the major active component of TCSF preparations.

Amino Acid Sequence↗
PubMed1990

Identification and characterization of heparan sulfate-binding proteins from human lung carcinoma cells.

The heparan sulfate proteoglycan/heparin-binding proteins of the human lung carcinoma cell line LX-1 have been identified, partially purified, and characterized. Analysis of the binding of [3H]heparin to membranes isolated from LX-1 cells indicated the presence of two classes of binding sites, with Kd values of approximately 2 x 10(-10) and 4 x 10(-8) M and corresponding Bmax values of 1 x 10(5) and 2 x 10(7) binding sites/cell. Binding was also observed with isolated heparan sulfate chains and with intact heparan sulfate proteoglycan isolated from two different cell types. With each ligand, binding was inhibited by addition of unlabeled heparin. The binding proteins were extracted from LX-1 cell membranes in detergent solution, and two size classes of binding proteins were identified by overlaying transblots of electrophoretically separated proteins with radioactive ligands. These two classes of binding proteins were shown to contain doublets with estimated molecular masses of approximately 16 kDa (HSBP1A and HSBP1B) and approximately 32 kDa (HSBP2A and HSBP2B). The proteins were partially purified by heparin-Sepharose chromatography and shown to bind heparin and heparan sulfate proteoglycan. By amino acid composition, N-terminal amino acid sequence, and reactivity with antibody, HSBP1A was shown to be very similar to histone 2B; HSBP1B may also be related to histone 2A. HSBP2A and HSBP2B, however, did not react with antibodies to the major histones and had compositions different from one another and from HSBP1.

Amino Acid Sequence↗
PubMed1990

A new method for evaluation of urinary autocrine motility factor and tumor cell collagenase stimulating factor as markers for urinary tract cancers.

Over the past several years, many tumor markers, including cell surface antigens, T-antigen, ras p55, and ras p52 proteins, have been studied as potential tumor markers of bladder cancer. The lack of specificity and inconsistency of these markers led us to develop a new method for studying the urinary excretion of autocrine motility factor (uAMF) and tumor cell collagenase stimulating factor (TCSF) in 24-hour and first morning voided specimens. AMF is a glycoprotein secreted by the malignant cells and is responsible for cell locomotion, a key event in invasion and metastases of the malignant cells. TCSF is a membrane bound glycoprotein of tumor cells that stimulates fibroblast collagenase production. We have utilized an enzyme-linked immunoabsorption assay to detect the levels of uAMF and TCSF in urine samples collected from normal volunteers, patients with benign diseases, and patients with bladder cancer. Our data indicate that urinary concentrations of uAMF and TCSF are elevated in patients with bladder cancer. Furthermore, the levels of uAMF and TCSF are more elevated in invasive tumors as compared with benign counterparts. We have localized uAMF and TCSF in bladder cancer cells, utilizing immunohistologic techniques.

Antigens, CD↗
PubMed1990

Vanadate treatment of streptozotocin diabetic rats restores expression of the insulin-responsive glucose transporter in skeletal muscle.

Streptozotocin-treated rats were diabetic, as assessed by blood glucose and plasma insulin values, while vanadate treatment restored blood glucose values to normal. Immunoblot analysis using a monoclonal antibody to the insulin-responsive glucose transporter demonstrated a 70% decline in transporter expression in skeletal muscle of diabetic rats. Subsequent treatment of diabetic animals with vanadate resulted in renewed expression of the transporter to 87% of control levels. Northern blot analysis of total skeletal muscle RNA from diabetic animals revealed a 55% decline in the steady state level of muscle glucose transporter mRNA, while vanadate treatment led to a 187% increase in transporter mRNA over normal levels. These results support the conclusion that vanadate acts to relieve diabetic hyperglycemia by inducing expression of the insulin-responsive glucose transporter at the pretranslational level.

Animals↗
PubMed1989

Decreased expression of the insulin-responsive glucose transporter in diabetes and fasting.

Cellular resistance to insulin caused by a reduction in insulin-mediated glucose uptake can be produced in rats by chemically inducing diabetes with streptozotocin and by fasting. Two glucose transporter isoforms are expressed in fat cells: (1) the insulin-responsive species which is found only in fat and muscle, and (2) a species corresponding to the erythrocyte/Hep G2/rat brain transporter. We show here that fat cells isolated from streptozotocin diabetic rats and from fasted rats show a significant (60-80%) decrease in the amount of immunologically detectable insulin-sensitive glucose transporter and no change in the level of the Hep G2/rat brain transporter. Administration of insulin and refeeding, respectively, result in a return of the insulin-sensitive glucose transporter to levels that are normal or slightly above normal. Thus, peripheral tissue insulin resistance could be due to the specific reduction in the amount of insulin-sensitive glucose transporter.

Adipose Tissue↗
PubMed1989

Monoclonal antibody preparation and purification of a tumor cell collagenase-stimulatory factor.

Tumor cells from several sources produce a factor(s) which stimulates fibroblast collagenase production. Monoclonal antibodies have been raised against the tumor cell collagenase-stimulatory factor from LX-1 human lung carcinoma cells and have been used for purification of the factor from LX-1 cell membranes. These purified preparations stimulated fibroblast collagenase production, and 80% of these preparations contained a single Mr approximately 58,000 protein detectable by immunoblotting; the other 20% contained an additional minor component with a molecular weight of 35,000. A single protein with a molecular weight of approximately 58,000 was also detected in radiolabeled preparations of the purified factor by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and autoradiography. Conditioned media from LX-1 cells contain several species with molecular weights lower than 58,000 which are immunologically cross-reactive with the membrane-derived factor. Immunofluorescence analysis indicates that the tumor cell collagenase-stimulatory factor is distributed on the outer surface of LX-1 cells and is absent from the cell surface of fibroblasts. These and previous results indicate that the factor is present on the tumor cell surface, is released into conditioned media possibly after proteolytic cleavage, and appears to have an important role in inducing collagenolysis of host stroma during tumor invasion.

Animals↗
PubMed1989

The role and regulation of tumour-associated hyaluronan.

Significantly increased levels of the glycosaminoglycan hyaluronan are often associated with human and animal tumours. In the rabbit V2 carcinoma elevated levels of tumour-associated hyaluronan are also closely correlated with invasiveness. We have therefore initiated studies to better define the role and regulation of hyaluronan synthesis in tumour tissues. In cell culture many tumour cell types have reduced capacities to synthesize hyaluronan even when derived from tumours enriched in hyaluronan. We showed that several of these same cells can nevertheless stimulate hyaluronan synthesis by normal fibroblasts. In the LX-1 human lung carcinoma cell line this stimulatory potential resides in a membrane-bound, heat-sensitive, lipophilic, cell surface glycoprotein. These data suggest that production of tumour-associated hyaluronan occurs via tumour-stromal cell interactions. We recently demonstrated that some human tumour cells also possess unoccupied, high affinity, cell surface binding sites for hyaluronan which may allow tumour cells to interact directly with hyaluronan-enriched extracellular matrices. This interaction may in turn allow tumour cells to use hyaluronan as a support for adhesion and locomotion. The spatial organization of hyaluronan could then function to guide tumour cells into surrounding stroma. We attempted to visualize this spatial deposition of hyaluronan in situ within frozen sections of human tumour tissue using a morphological probe that specifically recognizes hyaluronan. Hyaluronan appears most prominently in the partially degraded connective tissue.

Animals↗
PubMed1989

Bilateral pneumothorax following tracheal intubation.

An elderly patient undergoing elective cholecystectomy, developed bilateral pneumothorax following intubation of the trachea and manual ventilation of the lungs. Diagnosis was confirmed by chest x-ray and drainage with wide bore cannulae. Drainage of the chest was necessary.

Aged↗
PubMed1989

Coordinate increase in collagenase mRNA and enzyme levels in human fibroblasts treated with the tumor cell factor, TCSF.

Cocultures of human fibroblasts and LX-1 human lung carcinoma cells expressed 8-10 fold higher levels of collagenase mRNA than the sum of the individual cells, in parallel with similar increases in collagenase activity. Addition of the tumor cell collagenase stimulatory factor, TCSF, purified from LX-1 cells, to these fibroblasts also gave a 3-4 times increase in collagenase mRNA level. However, various fibroblast cell lines differed in their response to TCSF stimulation. Thus one cell line, GM 1391, did not respond to TCSF but responded to another potent collagenase stimulator, tetradecanoyl phorbol ester. Another cell line 5383 did not respond significantly to either agent. In each case collagenase activity and mRNA levels responded in a parallel fashion.

Cell Line↗
PubMed1988

Heparin and heparan sulfate binding sites on B-16 melanoma cells.

We have reported previously that the production of a tumor cell factor that stimulates synthesis of fibroblast collagenase is influenced by a fibroblast-deposited matrix component, possibly heparan sulfate-proteoglycan. In this study, binding sites for heparin and heparan sulfate on mouse B-16 melanoma cells have been demonstrated. Binding of 3H-heparin and 35S-heparan sulfate has been shown to occur to whole cells, isolated membranes, and to a component(s) of detergent extracts of the membranes. Scatchard analysis of binding of 3H-heparin yielded a Kd of 2-5 x 10(-8) M and a Bmax of 0.5 x 10(7) heparin molecules bound per cell. Binding of 35S-heparan sulfate was of at least an order of magnitude lower affinity than heparin, but the Bmax was similar to that for heparin. Competition studies showed that 35S-heparan sulfate binding was inhibited totally by heparin and heparan sulfate and partially by dermatan sulfate, but no inhibition was obtained with hyaluronate or chondroitin sulfate. Binding of 3H-heparin was inhibited totally by heparin but to different extents by preparations of heparan sulfate from different tissue sources. The heparin/heparan sulfate binding activity is a protein(s) because it is destroyed by treatment with trypsin. Binding of 3H-heparin to transblots of the detergent extract of the B-16 cell membranes indicated that at least part of the binding activity is a 14,000-dalton protein.

Animals↗
PubMed1987

Membrane association of collagenase stimulatory factor(s) from B-16 melanoma cells.

Past studies have shown that contact between tumor cells and fibroblasts results in stimulation of collagenase production by the fibroblasts. Membrane fractions prepared by differential centrifugation of sonicated B-16 melanoma cells were shown here to contain a collagenase stimulatory factor(s) (CSF). Trypsin treatment of intact B-16 cells prior to membrane fractionation led to loss of 90% of the total activity, indicating that CSF is localized on the outer surface of the cells. Stimulation of fibroblast collagenase production was also observed with dialyzed octylglucoside extracts of the B-16 membranes. Additional of exogenous lipid, ie, a mixture of phosphatidylcholine and phosphatidylserine, to the detergent extract of the membranes followed by dialysis and centrifugation at 100,000g resulted in 80% recovery of the factor activity in the pellet containing reconstituted lipid vesicles. Fractionation of tritium-labeled, reconstituted lipid vesicles on a Sephacryl S-300 column revealed that the collagenase stimulatory factor coeluted with the radioactive lipid vesicles. The fractionated lipid vesicles lost stimulatory activity completely after trypsin treatment or heating at 65 degrees C, indicating that the factor is a protein.

Animals↗
PubMed1987

The stimulation of collagenase production in rabbit articular chondrocytes by interleukin-1 is increased by collagens.

Osteoarthritis is characterized by a loss of articular cartilage due at least in part to the action of degradative enzymes secreted by chondrocytes. We have investigated the effect of type II collagen from cartilage and interleukin 1 on collagenase production in cultures of rabbit articular chondrocytes. Interleukin 1 alone stimulated the chondrocytes to secrete collagenase but this response was increased as much as fivefold by the addition of rabbit type II collagen. Bovine type II and chick type I collagens were also stimulatory. The native form of the collagens was not required since denatured collagens and purified chick type II alpha chains were effective. The observed effects of collagens and interleukin 1 may contribute to the progressive nature of osteoarthritis.

Animals↗
PubMed1985

Matrix influence on the tumor cell stimulation of fibroblast collagenase production.

Cocultures of rabbit fibroblasts and mouse B-16 melanoma cells produce increased levels of collagenase against type I collagen. This stimulatory effect was also found when fibroblasts were cultured in conditioned media from tumor cells. However, the level of the stimulatory factor in conditioned media was influenced by matrix deposited by fibroblasts. Thus, conditioned media collected from monolayers of B-16 plated on fibroblast matrix consistently showed high levels of the factor activity. The influence of the matrix on the level of the factor was not removed by treating the fibroblast matrix with collagenase or chondroitinase ABC and was not reproduced by collagen-coated dishes.

Animals↗
PubMed1984

Stimulation of glycosaminoglycan production in murine tumors.

Three types of murine tumors, B-16 melanoma, A-10 carcinoma, and S-180 sarcoma, were shown to contain elevated glycosaminoglycan (GAG) concentrations in vivo as compared to normal muscle or subcutaneous tissue. Hyaluronate was especially concentrated in the A-10 carcinoma, which contained approximately six times more hyaluronate than subcutaneous tissue and 18 times more than muscle. In all three tumors, chondroitin sulfates, especially chondroitin-4-sulfate, were present in higher concentrations than in the normal tissues. In culture, however, all three tumor cell lines produced less than 5% as much GAG as mouse fibroblasts, when measured by incorporation of [3H] acetate or by chemical analysis. Varying the culture passage number or the medium composition, ie, glucose, serum, and insulin concentrations, had little effect on GAG synthesis by the tumor cells. The low GAG levels in the tumor cell cultures were not due to hyaluronidase activity in their media. In an attempt to mimic possible host-tumor cell interactions that could account for the elevated GAG levels in vivo, tumor cells were cocultured with fibroblasts, but no stimulation above the amount made by the tumor cells alone plus that by the fibroblasts alone was observed. Conditioned media from the tumor cells, either dialyzed or not against fresh complete medium, had no effect on fibroblast GAG synthesis. Tumor extracts, however, were found to stimulate synthesis of hyaluronate by fibroblasts. Stimulation by extracts of A-10 carcinoma was greater than and additive to that of serum. The above results strongly suggest that GAG production in these tumors is in part regulated by host-tumor interactions.

Acetates↗