Changes in the lactate dehydrogenase isoenzyme spectrum during T-lymphocyte differentiation

The pattern of lactate dehydrogenase isoenzyme spectrum changes on different stages of T-lymphocyte differentiation was studied An enriched population of stem cells has LDH-5, 4 and 3 isoenzymes, and much less LDH-2 activity. The isoenzyme pattern of thymic cell precursors consists of LDH-5, 4, 3 and 2. All the five LDH isoenzymes were found in cortical thymocytes. Medullary thymocytes reveal LDH-5, 4 and 3 isoenzymes. T-lymphocytes of peripheral lymphoid organs contain mainly LDH-5 and in a lesser degree LDH-4 activity.     

Additional lactate dehydrogenase (LDH) isoenzymes in normal testis and spermatozoa of adult man

Summary Adult human testicular tissue contains up to six previously undescribed lactate dehydrogenase (LDH) isoenzymes in addition to the five LDH isoenzymes normally found and the sixth found in spermatogenic cells and spermatozoa, LDH-X. Additional LDH isoenzymes were also found in spermatozoa but not in seminal fluid or in serum. After electrophoresis one additional LDH isoenzyme of testicular tissue was localized between LDH-1 and LDH-2, two between LDH-2 and LDH-3, two between LDH-3 and LDH-4, and two between LDH-4 and LDH-5. These localizations indicate that the additional LDH isoenzymes are tetramers combining the A and B subunits of the five normal LDH isoenzymes and the C subunit of LDH-X. The additional LDH isoenzymes may be important in the metabolism of spermatogenic germ cells and spermatozoa.     

Lactate dehydrogenase isoenzyme 1 (LDH-1) in athymic mice with xenografts of a human testicular germ cell tumor

Summary Lactate dehydrogenase (LDH) and LDH isoenzyme activities were determined in tumor tissue, tumor cystic fluid, and serum from athymic mice with transplants of a human testicular germ cell tumor. High activity of LDH-1 was found in tumor tissue and tumor cystic fluid. By histochemical staining LDH was found in all tumor cells. Most tumor cells had a faint staining reaction while some cells dispersed throughout the tumor had a strong staining reaction. The serum LDH-1 in athymic mice with tumor transplants correlated markedly with the tumor volume. The results indicate that serum LDH-1 was derived from the testicular germ cell tumor transplants.     

Synthesis and biological evaluation of novel steroidal[17,16-d][1,2,4]triazolo[1,5-a]pyrimidines

The preparation of steroidal[17,16-d][1,2,4]triazolo[1,5-a]pyrimidines and their biological evaluation as potential anticancer agents are herein reported. These novel heterosteroids (2, 4) were prepared through the condensation reaction of 3-amino-1,2,4-triazole with 16-arylidene-17-ketosteroids (1, 3). All the synthesized compounds were evaluated for their anticancer activity in vitro against PC-3 (human prostatic carcinoma), MCF-7 (human breast carcinoma) and EC9706 (human esophageal carcinoma) cell lines. Among the screened compounds, 2i, 2n and 4f showed significant inhibitory activity against all the three human cell lines.     

Olfactory ensheathing glia and Schwann cells: two of a kind?

Prostatic carcinoma affects 1 in 11 men and targets bone with sclerotic metastases. The study of prostate carcinoma growth in bone has been hampered by the lack of suitable animal models. We have developed an in vivo model of prostate carcinoma growth in bone by inoculating three human prostate carcinoma cell lines (PC-3, DU-145, and LNCaP) into the tibia of congenitally athymic mice. Developing tumors were analyzed by radiographic, histologic, immunohistochemical, and in situ hybridization examination. Seven of the nine PC-3 inoculated mice and all (9/9) of the DU-145 inoculated mice developed tumors in the injected limb. In contrast, inoculation with LNCaP cells failed to produce tumors (0/9). Radiologically, the tumors had a mixed sclerotic/lytic appearance with extracortical extension. All the PC-3 tumors invaded the bone marrow cavity, cortical bone, and surrounding soft tissue. The DU-145 tumors were confined to the bone marrow cavity in 7/9 animals. CK18 and Ki67 localization identified the human tumor cells and their proliferative activity, respectively. The PC-3- and DU-145-induced tibial tumors expressed alpha(1)I procollagen and osteopontin mRNA, to varying degrees. All the tumors demonstrated an up-regulation of osteoclasts at the bone/tumor interface compared with the control limbs. Thus, this is a reliable and reproducible in vivo model of prostate carcinoma growth in bone enabling the study of the interactions that occur between prostate cancer cells and bone at an important part of the metastatic cascade, namely, growth and invasion at a distant site.     

Prostaglandin E2 concentrations in naturally occurring canine cancer

The purpose of this study was to determine the PGE2 concentration in naturally-occurring cancer in pet dogs and in canine cancer cell lines in order to identify specific types of canine cancer with high PGE2 production which could serve as preclinical models to evaluate anticancer strategies targeting PGE2. PGE2 concentrations were measured by enzyme immunoassay in canine melanoma, soft tissue sarcoma, transitional cell carcinoma, osteosarcoma, and prostatic carcinoma cell lines; in 80 canine tumor tissue samples including oral melanoma (MEL), oral squamous cell carcinoma (SCC), transitional cell carcinoma of the urinary bladder (TCC), lymphoma (LSA), mammary carcinoma (MCA), osteosarcoma (OSA), prostatic carcinoma (PCA); and in corresponding normal organ tissues. High concentrations of PGE(2)(range 400-3300 pg/10(4)cells) were present in cell culture medium from the transitional cell carcinoma, prostatic carcinoma, and osteosarcoma cell lines. PGE2 concentrations in tumor tissues were elevated (tumor PGE2 concentration>mean+2X sd PGE(2)concentration of normal organ tissue) in 21/22 TCC, 5/6 PCA, 7/10 SCC, 5/10 MEL, 3/8 MCA, 4/15 OSA, and 0/9 LSA. Results of this study will help guide future investigations of anticancer therapies that target cyclooxygenase and PGE2.     

Parathyroid hormone-related protein upregulates integrin expression via an intracrine pathway in PC-3 prostate cancer cells

Parathyroid hormone-related protein (PTHrP) is expressed by human prostatic tissue and prostate cancer cell lines, and enhances prostate tumor cell growth both in vivo and in vitro. PTHrP expression also plays a role in the development of bone metastasis, which is a frequent complication in patients with prostate carcinoma. Tumor cell adhesion to extracellular matrix (ECM) components is mediated via integrin subunits, and plays a major role in the invasion and metastasis of tumor cells. We previously showed that PTHrP overexpression increases adhesion of the human prostate cancer cell line PC-3 to the ECM molecules collagen type I, fibronectin, and laminin. Increased adhesion is accompanied by upregulation in the expression of alpha1, alpha5, alpha6, and beta4 integrin subunits. We used the same cell line to study the mechanism via which PTHrP upregulates integrin expression. Clonal PC-3 cells were established overexpressing wild-type PTHrP or PTHrP mutated in the nuclear localization sequence (NLS). Mutation of the NLS negated the effects of PTHrP on alpha1, alpha5, alpha6, and beta4 integrin expression, indicating that these effects are mediated via an intracrine pathway requiring nuclear localization. Expression of the alpha2, alpha3, alphav, and beta1 integrin subunits were comparable in wild-type and NLS-mutated PTHrP transfectants. These findings indicate that PTHrP may play a role in prostate tumor invasion and metastasis by upregulating the expression of specific integrin subunits via an intracrine pathway.     

Inhibition of osteoblastic cell differentiation by conditioned medium derived from the human prostatic cancer cell line PC-3 in vitro

Human prostatic carcinoma frequently metastasizes to bone tissue and activates bone metabolism, especially bone formation, at the site of metastasis. It has been reported that an extract of prostatic carcinoma and conditioned medium (CM) of a human prostatic carcinoma cell line, PC-3, established from a bone metastastic lesion, stimulate osteoblastic cell proliferation. However, there is little information about the effect of PC-3 CM on the differentiation of osteoblastic cells. In this study, we investigated the effect of PC-3 CM on the differentiation of two types of osteoblastic cells, primary fetal rat calvaria (RC) cells containing many undifferentiated osteoprogenitor cells, and ROS 17/2.8, a well-differentiated rat osteosarcoma cell line. PC-3 CM inhibited bone nodule formation and the activity of alkaline phosphatase (ALPase), an osteoblastic marker enzyme, on days 7, 14, and 21 (RC cells) or 3, 6, and 9 (ROS 17/2.8 cells) in a dose-dependent manner (5–30% CM). However, the CM did not affect cell proliferation or cell viability. PC-3 CM was found to markedly block the gene expression of ALPase and osteocalcin (OCN) mRNAs but had no effect on the mRNA expression of osteopontin (OPN), the latter two being noncollagenous proteins related to bone matrix mineralization. These findings suggest that PC-3 CM contains a factor that inhibits osteoblastic cell differentiation and that this factor may be involved in the process of bone metastasis from prostatic carcinoma. J. Cell. Biochem. 67:248–256, 1997. © 1997 Wiley-Liss, Inc.     

Noninvasive discrimination between human normal and cancer cells by analysis of intracellular distribution of phase-shift data

Aiming to establish a method for the noninvasive discrimination of cancer cells from normal cells in adherent culture, we investigated to employ all phase shift data for all pixels inside a cell. The bird’s-eye views of phase shifts of human prostate epithelial cells (PRECs) and human prostatic carcinoma epithelial cell (PC-3) lines acquired by phase-shifting laser microscopy showed tableland and cone shapes, respectively, while treatment of PRECs with cytochalasin D resulted in the cone shape. So, the profile of phase shift in both sections towards the x- and y-axes of the views through the peaks of the phase shifts in PRECs and PC-3 cells were trapezoid-like and triangle-like, respectively. Typical profiles of phase shifts in a section in PRECs or PC-3 cells were calculated by averaging from 10 cells and smoothing. Cancer index is defined as the deduction of sums of the squared difference between a real cell and the typical profiles for a PREC and a PC-3 cell. The cancer indices for PC-3 and hepatocellular carcinoma cell lines were positive, while those for PRECs and human normal cryopreserved hepatocytes were negative. Cancer indices along the major axis of fibroblast-like cells of normal mesenchymal stem cells and the osteosarcoma cell line were negative and positive, respectively. Consequently, several cancer cells could be noninvasively discriminated from normal cells by calculating the cancer index employing phase shift for all pixels inside the cells.     

Parathyroid hormone-related protein enhances PC-3 prostate cancer cell growth via both autocrine/paracrine and intracrine pathways

Parathyroid hormone-related protein (PTHrP) is expressed by human prostatic tissue and prostate cancer cell lines, and positively influences primary prostate tumor growth in vivo. The human prostate cancer cell line PC-3, which expresses functional PTH/PTHrP receptors, was used as a model to study the effects of PTHrP on prostate cancer cell growth. Addition of PTHrP (1-34), (1-86), and (1-139) increased cell number and [3H]thymidine incorporation; these effects were reversed by anti-PTHrP antiserum. This antiserum also decreased endogenous PC-3 cell growth. Clonal PTHrP-overexpressing PC-3 cell lines also showed enhanced cell growth and [3H]thymidine incorporation and were enriched in the G2+M phase of the cell cycle, suggesting an effect of PTHrP on mitosis. Overexpression of PTHrP with the nuclear localization sequence (NLS) deletion partially reversed the growth-stimulatory effects. The growth rate of these cells was midway between that of wild-type PTHrP-overexpressing and control cells, presumably because NLS-mutated PTHrP is still secreted and acts through the cell surface PTH/PTHrP receptor. In contrast to NLS-mutated PTHrP, wild-type protein showed preferential nuclear localization. These results suggest that the proliferative effects of PTHrP in PC-3 cells are mediated via both autocrine/paracrine and intracrine pathways, and that controlling PTHrP production in prostate cancer may be therapeutically beneficial.     

Energy enzymes of the flight muscle of the house sparrow, Passer domesticus--III. Comparative physical properties of heart and flight muscle lactate dehydrogenase

Purification of heart (LDH-4) and flight muscle (LDH-2 and LDH-3) lactate dehydrogenase isoenzymes from the house sparrow, Passer domesticus, has been accomplished. Although these isoenzymes electrophoretically migrate reversed to most other vertebrate LDH isoenzymes, comparison of the amino acid compositions of LDH-4 and LDH-2-LDH-3 fails to reveal the basis for their reversed electrophoretic migration. Amino acid compositions did reveal mol. wts between 141,000-142,000 as well as vp of 0.744 ml/g (LDH-4) and 0.745 ml/g (LDH-2-LDH-3). SDS-gel electrophoresis yielded single bands for each preparation with mol. wts of 35,000 suggesting that LDH in this species exists as a tetramer. LDH-4 has a lower Km for both pyruvate (0.005 mM) and NADH (0.002 mM) than does LDH-2-LDH-3 (0.062 mM for pyruvate, 0.013 mM for NADH).     

Selective inactivation of lactate dehydrogenase of rat tissues by sodium deoxycholate.

Soluble lactate dehydrogenase (EC 1.1.1.27) extracted from brain, skeletal and cardiac muscle and liver of rats, and purified isoenzymes LDH-1 and LDH-5, were incubated with sodium deoxycholate. Deoxycholate almost totally inactivated isoenzyme LDH-5 (A4), whereas it left isoenzyme LDH-1 (B4) unaffected. Tissue lactate dehydrogenase was inactivated to different degrees depending on the origin of the enzyme. Electrophoretic isoenzyme studies of tissue lactate dehydrogenase showed the loss of activity to be quantitatively related to the overall percentage of subunit A distributed among the homotetramer LDH-5 and the heterotetramers LDH-2, LDH-3 and LDH-4. It was concluded that subunit A of lactate dehydrogenase interacts selectively with deoxycholate, irrespective of its association with subunit B. Distinct changes in electrophoretic mobilities of deoxycholate-treated isoenzymes strongly indicated an indiscriminate binding of deoxycholate by all LDH isoenzymes, probably through hydrophobic interactions. The results suggest that the inactivation of the enzyme is non-competitive, but the basis of the selectivity of deoxycholate towards subunit A is not known at present.     

Gene expression and prostate specificity of human prostatic acid phosphatase (PAP): evaluation by RNA blot analyses.

A fragment of a complementary DNA (cDNA) clone for human prostatic acid phosphatase (PAP) (EC 3.1.3.2.) was used to study the expression of corresponding mRNA in human tissues. The specificity of its expression in benign prostatic hyperplasia (BPH) and prostatic carcinoma tissues were indicated in RNA blot analyses. The PAPcDNA probe did not recognize any specific mRNAs in RNAs extracted from human liver cancer, lung cancer, pancreatic cancer, placenta, breast cancer cells (MCF-7), mononuclear blood cells or acute promyelocytic leukemia cells (HL-60), according to Northern blot analysis. mRNA for PAP was detected in the androgen-dependent human prostatic cancer cell line LNCaP, but not in the androgen-insensitive human prostatic cancer cell line PC-3. In contrast, lysosomal acid phosphatase (LAP) mRNA was detected in both of these human prostatic cancer cell lines. Our findings indicate a high specificity for the PAP gene in prostatic tissue. The mean abundance for the PAPmRNA expression was 0.26 for prostatic carcinoma samples (n = 11) and 0.46 for BPH samples (n = 8) according to slot-blot analysis. The differences observed between the different categories of prostatic tissue in PAPmRNA abundances call for additional studies on regulation of its expression.     

Mutation Analyses of 268 Candidate Genes in Human Tumor Cell Lines

We have performed a homozygous deletion screen on 268 candidate genes in 90 human tumor cell lines derived from multiple types of cancers. Most of the candidate genes investigated have been proposed to be involved in cellular processes that are germane to cancer progression, such as cell cycle control, genome maintenance, chromatin remodeling, cell adhesion, and apoptosis. We have detected novel homozygous deletions affecting four independent loci: Brahma-related gene (SMARCA4) on chromosome 19p in the TSU-Pr1 prostate and A427 lung carcinoma lines, Map Kinase Kinase 3 (MAP2K3) on 17q in the NCI-H774 lung tumor cell line, TMPRSS2 on 21q in the Bx PC-3 pancreatic carcinoma line, and Cadherin 6 (CDH6) on 5p in the SK-LU-1 lung carcinoma line. Subsequent analyses of the coding sequences of these four genes using cDNAs from a panel of tumor cell lines revealed multiple sequence variants. The results of this mutation study serve to demonstrate the feasibility of performing high-throughput screens of candidate genes in tumor cell lines to identify genes that may be targeted for mutation during the development of cancer.     

Factors influencing phenotypic diversity of human prostate carcinoma cells metastasizing in athymic nude mice

Three related human prostate carcinoma cell lines, PC-3, 1-LN-PC-3-1A (1-LN), and 1-LN-PC-3-1A clone 4 (clone 4) were compared in terms of relative metastatic capacity in adult and young male nude mice. Only 1-LN produced lung metastases after intravenous injection into both 6- to 8-week-old and 4-week-old nude mice, as well as in mice injected intraperitoneally. The extent of the phenotypic diversity exhibited by these human prostate tumor lines was influenced by inherent dissemination ability, age of the host, and route of injection. These lines provide a useful system for the analysis of the biology of human tumor metastasis in nude mice.     

Effects of electrogenetherapy with p53wt combined with cisplatin on curvival of human tumor cell lines with different p53 status

The aim of our study was to evaluate electrogenetherapy with p53wt alone or combined with cisplatin on two colorectal (HT-29 and LoVo) and two prostatic (PC-3 and Du145) carcinoma cell lines with different p53 status. In addition, the feasibility of electrogenetherapy with p53wt was tested also in vivo on PC-3 prostatic cancer xenografts. Electrogenetherapy with p53wt was dependent on the p53 status of the cell lines used. Electrogenetherapy was the most effective on the PC-3 (p53 null) and Du145 (p53mt) cells, and to the much lesser extent in LoVo cells (p53wt). The exception was the HT-29 cell line with overexpressed mutated p53, where electrogenetherapy with p53wt was the least effective. Sensitivity of the cell lines to cisplatin was independent of the p53 status. Furthermore, the presence of exogenous p53 due to electrogenetherapy did not enhance cisplatin cytotoxicity, since the combination of these therapies resulted in additive cytotoxic effect. The effectiveness of electrogenetherapy with p53wt was also demonstrated in vivo by successful treatment of subcutaneous PC-3 tumors in mice. In conclusion, our study shows that electrogenetherapy with p53wt is feasible, and resulted in comparable cytotoxic and antitumor effectiveness to viral-mediated p53wt gene therapy. This therapy was effective and dependent on the p53 status of the tumor cell lines. Combination of electrogenetherapy and cisplatin resulted in additional cell kill by cisplatin, and was not dependent on the p53 status.     

Lectin-induced alterations on the proliferation of three human prostatic cancer cell lines

Summary While lectins are known to influence the cell growth of several types of normal and neoplastic tissues, their roles in the case of prostatic cancer cells remain relatively unexplored. In the present work, we report thein vitro influence of five lectins, namely peanut (PNA), wheat germ (WGA), Concanavalin A (Con A),Griffonia simplicifolia (GSA-IA₄), andPhaseolus vulgaris (PHA-L) agglutinins, on the cell proliferation of one androgen-sensitive (LNCaP) and two androgen-insensitive (PC-3 and DU 145) human prostatic cancer cell lines cultured in either 10% or 1% fetal bovine serum (FBS)-supplemented media. The cell proliferation was assessed by means of the colorimetric 3-(4,5-dimethythiazol-2-yle)2,5-diphenyltetrazolium bromide. (MTT) assay. Four lectin concentrations were tested (i.e., 0.1, 1, 10, and 100 μg/ml) at five experimental states (i.e., 2, 3, 5, 7, and 9 d following the addition of each lectin to the culture media). Our results demonstrated that the five lectins under study had a globally significant dose-dependent toxic effect on prostatic cancer cell proliferation. Nevertheless, low doses of GSA-IA₄ and PHA-L significantly (P<0.05 toP<0.001) increased the cell proliferation of confluent PC-3 cells. Increasing the FBS from 1% to 10% in the culture media significantly antagonized lectin-induced toxicity in the three prostatic cell lines. In conclusion, the present data strongly suggest that some lectins might influence the proliferation of prostatic carcinoma cells. In addition, because lectins are present in our diet, and are able to pass into the systemic circulation and thus reach the prostate, the present results suggest that some lectins might exert an influence on prostate cancer growth under clinical conditions.     

Hepatitis a virus infection of HBsAg-producing hepatocellular carcinomas in athymic mice

Summary Two human hepatocellular carcinoma cell lines were grown in athymic mice. Morphologically, the tumors resembled hepatocellular carcinomas. HBsAg, anti-HBs, and -fetoprotein were detected in sera of mice bearing tumors of PLC/PRF/5 or Hep 3B cells; their amounts correlated with tumor weight. Tumors of both cell lines were infected with cell culture-adapted hepatitis A virus (HAV); HAV antigen and infectious virus were recovered from infected tumors of PLC/PRF/5 and Hep 3B cells. Our results indicate that HAV-infected tumors may be useful in studying the production in vivo of hepatitis A virus antigen.     

Expression of heat shock proteins and heat shock protein messenger ribonucleic acid in human prostate carcinoma in vitro and in tumors in vivo

Heat shock proteins (HSPs) are thought to play a role in the development of cancer and to modulate tumor response to cytotoxic therapy. In this study, we have examined the expression of hsf and HSP genes in normal human prostate epithelial cells and a range of prostate carcinoma cell lines derived from human tumors. We have observed elevated expressions of HSF1, HSP60, and HSP70 in the aggressively malignant cell lines PC-3, DU-145, and CA-HPV-10. Elevated HSP expression in cancer cell lines appeared to be regulated at the post-messenger ribonucleic acid (mRNA) levels, as indicated by gene chip microarray studies, which indicated little difference in heat shock factor (HSF) or HSP mRNA expression between the normal and malignant prostate cell lines. When we compared the expression patterns of constitutive HSP genes between PC-3 prostate carcinoma cells growing as monolayers in vitro and as tumor xenografts growing in nude mice in vivo, we found a marked reduction in expression of a wide spectrum of the HSPs in PC-3 tumors. This decreased HSP expression pattern in tumors may underlie the increased sensitivity to heat shock of PC-3 tumors. However, the induction by heat shock of HSP genes was not markedly altered by growth in the tumor microenvironment, and HSP40, HSP70, and HSP110 were expressed abundantly after stress in each growth condition. Our experiments indicate therefore that HSF and HSP levels are elevated in the more highly malignant prostate carcinoma cells and also show the dominant nature of the heat shock-induced gene expression, leading to abundant HSP induction in vitro or in vivo.     

大豆黄酮对衰老小鼠脑组织SOD、LDH同工酶的影响

利用SOD和LDH同工酶电泳分析,研究大豆黄酮对衰老小鼠的抗氧化作用。结果显示大豆黄酮没有改变SOD和LDH同工酶谱的特征,但对因衰老引起的小鼠脑组织LDH和SOD同工酶活性、各组分的相对活性和比活力的变化有不同程度的改善作用,即LDH同工酶中LDH-2、LDH-3的活性明显下降,LDH-1的活性下降最为明显,而LDH-4的活性有所下降,但不显著,LDH-5的活性几乎没有变化,SOD同工酶的SOD-1和SOD-2的活性有不同程度的升高。这表明大豆黄酮是通过抑制LDH同工酶H亚基的合成来降低LDH的活性,而对M亚基的合成没有影响,并且能够促进SOD同工酶SOD-1和SOD-2的合成,不影响其遗传稳定性。