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British Journal of Healthcare and Medical Research - Vol. 11, No. 5

Publication Date: October 25, 2024

DOI:10.14738/bjhmr.115.17644.

Gonen, C. (2024). PMA Induction to Prostate Cancer Cell Lines: DU145 and LNCaP. British Journal of Healthcare and Medical

Research, Vol - 11(5). 86-94.

Services for Science and Education – United Kingdom

PMA Induction to Prostate Cancer Cell Lines: DU145 and LNCaP

Ceren Gonen

Ege Univ. Pharmacy Fac. Pharmacology Dept.Bornova, Izmir, Turkiye

ABSTRACT

Prostate cancer is the most commonly diagnosed cancer and the second leading

cause of cancer mortality in men in the Western World. The effects of androgens are

mediated by the Androgen Receptor (AR). Therefore, studies focus on the

identification of AR-regulated genes that are also highly expressed in the prostate.

STAMP family genes STAMP1/STEAP2 and STAMP2/STEAP4 have only expressed in

androgen receptor-positivecells, the role of AR in STAMP family gene expression is

an important question Phorbol 12-myristate 13-acetate, NF-κB Activator, PMA, TPA

PMA is used at 100nM final concentration after transfection of Hismax vector and

Hismax- STAMP1 to DU145-brain metastases of prostate cancer cell line. DU145 cell

line kinetics were shown. PMA induction to LNCaP cells.was done. In summary, the

data presented showthat STAMP1 is involved in a signaling pathway that is linked

to cell cycle progression as well as inhibition of apoptosis. Consistent with its

increased expression in prostate cancer, these data suggest that STAMP1 may play

important roles in prostate cancer development andprogression.

Keywords: DU145, LNCaP, PMA, RT-PCR, STAMP1, AR: Androgen receptor, ARRE:

Androgen receptor response element, LNCaP Lymph Node Metastases Prostate Cancer

Cell Line, PMA: Forbol Miristal Asetat, STAMP: six transmembrane protein of prostate,

RTqPCR: Quantitative polymerase chain reaction TUBA the Turkish Academy of

Sciences, TUBITAK The Scientific and Technological Research Council of Turkey

INTRODUCTION

STEAP (Six Transmembrane Epithelial Antigens of Prostate) is the first characterized prostate

enriched six transmembrane genes, expressed in metastatic prostate cancer samples, it is

tempting to speculate that STAMP/STEAP family genes may be involved in similar functions

with a role for both the normal biology and pathophysiology of the prostate.

Phorbol 12-myristate 13-acetate (PMA), also known as 12-O-tetradecanoylphorbol 13- acetate

(TPA), is a specific activator of Protein Kinase C (PKC) and hence activates nuclear factor-kappa

B (NF-κB). NF-κB is a transcription factor that regulates numerous physiological functions and

is involved in the pathogenesis of various diseases. It has been identified as a potential

therapeutic target in inflammatory processes, cancer, and autoimmunediseases.

PMA is the most common and potent phorbol ester. It is active at nanomolar concentrationsand

activates NF-κB in a dose-dependent manner. PMA causes a wide range of effects in cells and

tissues and is a very potent mouse skin tumor promoter.

InvivoGen’s PMA is designed to study the NF-κB pathway in cellular assays.

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Gonen, C. (2024). PMA Induction to Prostate Cancer Cell Lines: DU145 and LNCaP. British Journal of Healthcare and Medical Research, Vol - 11(5).

86-94.

URL: http://dx.doi.org/10.14738/bjhmr.115.17644.

Because knockdown of STAMP1 increased cell death, it was of interest to investigate if there

were changes in STAMP1 levels in prostate cancer cells that are undergoing apoptosis.

Previous studies have established that apoptosis in LNCaP cells can be induced by various

agents. Prostate cancer is cancer of the prostate. The prostate is a gland in the male

reproductive system that surrounds the urethra just below the bladder. Most prostate cancers

are slow growing. Cancerous cells may spread to other areas ofthe body, particularly bones and

lymph nodes. It may initially cause no symptoms. In later stages, symptoms include painor

difficulty urinating, blood in the urine, or pain in the pelvis or back. Benign prostatic hyperplasia

may produce similar symptoms. Other late symptoms include fatigue, due to lowlevels of red

blood cells.

Factors that increase the risk of prostate cancer include older age, family history, and race.

About 99% of cases occur after age 50. A first-degree relative with the disease increases therisk

two- to three-fold. Other factors include a diet high in processed meat and red meat, while the

risk from a high intake of milk products is inconclusive.

NF-kappa B is a transcription factor found in all cell types. It is inactive in the cytoplasm. When

activated, it is transported to the nucleus. There are 5 types: NF-kB1, NF-kB2, RelA,RelB, and c- Rel. It is thought that NF-kappa B has an effect in some autoimmune diseases.

RESULTS

PMA used at 100nM final concentration after transfection of Hismax vector (1A) andHismax- STAMP1 (1B) to DU145-brain metastases of prostate cancer cell line.

1A DU145 cells transfected wirh HisMax-vector pMAinduced RT-PCR primers amplified.

Figure 1 A: DU145 cells transfected wirh HisMax-vector PMAinduced RT-PCR primersamplified.

1B DU145 cells transfected wirh HisMax-STAMP1 PMAinduced RT-PCR primersamplified.

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Services for Science and Education – United Kingdom

Figuree 1B: DU145 cells transfecred with HisMax-STAMP1 PMA induced RT-PCR primers

amplified

PMA induction to HisMax vector transfected DU145 cells caused mouse double minute gene2-

MDM2 –decrease p<0.001 (1A)

But transfection of STAMP1 changed PMA responses and Akt1, BAD, CASPASE9 and, P73

showed 5.6, 3.9, 3.3, 2. 9 fold increase. respectevly p<0.001 (1B).

1C: DU145 cell line kinetics: HisMax-Vector- HisMax-STAMP1, HisMax-STAMP2 andHisMax- STAMP3 transfected

Figure1C: DU145 cells transfected with STAMP constructs (STAMP1, 2 and 3 versusHisMax- vector) growth kinetic result

DU145 cells transfected with STAMP constructs (STAMP1, 2 and 3 versus HisMax- vector)

STAMP/STEAP genes transfection caused gradual growth in brain metastasis of prostate cancer

cell line-DU145 cells. Following the day of the transfection done with FuGene HD transfection

reagent, cells were taken to 12-well plates as 104 cells per well and dead cells were counted by

trypan-blue exclusion assay beginning at day 2 until 12. Six time points weretaken that assayed

as n=7 per point and growth kinetics were drawn (Figure 1C). It was shown that STAMP3

transfection caused relatively lower growth increase compare to control group in the

transfected cell group.

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Gonen, C. (2024). PMA Induction to Prostate Cancer Cell Lines: DU145 and LNCaP. British Journal of Healthcare and Medical Research, Vol - 11(5).

86-94.

URL: http://dx.doi.org/10.14738/bjhmr.115.17644.

PMA induction to LNCaP cells was done.

Caspase7 and 9 showed a decrease P<0.001 and MDM2 gave an incraese p<0.001(FIG2),

Figure 2: LNCaP cells induced wirh PMA, RT-PCR primers amplified

DISCUSSION

p53 or tumor protein 53 (TP53), Genome Guardian, anti-tumor p53 is a transcription factor

that regulates the cell cycle. It is a very important protein for suppressing cancer in many

organisms. It is critical as it inhibits cancer formation in multicellular vertebrates and exhibits

tumor suppressive function.

p73 is a protein associated with the p53 tumor protein. Because of its structural similarity to

p53, it has also been considered a tumor suppressor. It plays a role in cell cycle regulation and

apoptosis induction. Like p53, p73 is characterized by the presence of different isoforms of the

protein.

The murine double minute (MDM2) oncogene, which codes for the MDM2 protein, was

originally cloned, along with two other genes (MDM1 and MDM3) from the transformed mouse

cell line 3T3-DM. MDM2 overexpression, in cooperation with oncogenic Ras, promotes

transformation of primary rodent fibroblasts, and MDM2 expression led to tumor formation in

nude mice. The human homologue of this protein was later identified and is sometimes called

HDM2. Further supporting the role of MDM2 as an oncogene, several human tumor types have

been shown to have increased levels of MDM2, including soft tissue sarcomas and

osteosarcomas as well as breast tumors. The MDM2 oncoprotein ubiquitinates and antagonizes

p53, but may also carry out p53-independent functions. MDM2 supports the Polycomb- mediated repression of lineage-specific genes, independent of p53. MDM2 depletion in the

absence of p53 promoted the differentiation of human mesenchymal stem cells and diminished

clonogenic survival of cancer cells. Most of the MDM2-controlled genesalso responded to the

inactivation of the Polycomb Repressor Complex 2 (PRC2) and its catalytic component EZH2.

MDM2 physically associated with EZH2 on chromatin, enhancing the trimethylation of histone

3 at lysine 27 (H3K27me3) and the ubiquitination of histone 2A at lysine 119 (H2AK119) at its

target genes. Removing MDM2 simultaneously with the H2AK119 E3 ligase Ring1B/RNF2

further induced these genes and synthetically arrested cell proliferation.

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AKT1

AKT1 (gene at 14q32.33) is one of three closely related serine/threonine-protein kinases

(AKT1, AKT2, and AKT3) that regulate many processes including metabolism, proliferation, cell

survival, growth, and angiogenesis by phosphorylating a range of downstream substratesin

response to growth factor stimulation (i.e., EGF, IGF). AKT is responsible of the regulation of

glucose uptake by mediating insulin-induced translocation of the SLC2A4/GLUT4 glucose

transporter to the cell surface. It also regulates the storage of glucose in the form of glycogen.

AKT promotes cell survival via the phosphorylation of the apoptosis signal-related kinase

MAP3K5. Phosphorylation of “Ser-83” decreases MAP3K5 kinase activity stimulated by

oxidative stress and thereby prevents apoptosis. AKT has an important role in the regulation of

NF-kappa-B-dependent gene transcription and positively regulates the activity of the cyclic

AMP (cAMP)-response element binding protein (CREB1). The phosphorylation of CREB1

induces the binding of accessory proteins that are necessary for the transcription ofpro-survival

genes.

BAD: Bcl2 Antagonist of Cell Death

Yang et al. (1995) identified a new protein that binds to Bcl2. Antagonist of Bcl2-mediated cell

death: It is named Bcl2 antagonist of cell death: BAD. ' This 204-amino acid protein has

sequence similarity to the BH1 and BH2 domains of BCL2 family members. Bad shows strong

heterodimerization with BclX from this family, weaker binding with Bcl2 but no binding with

other members. In functional studies, it has been shown that Bax is removed as aresult of

dimerization of Bad with BclX and its apoptosis-inducing effect is eliminated.

BNIP

BNip (formerly known as Nip) proteins, including homologues isolated from human, mouse and

Caenorhabditis. elegans, are a relatively new subgroup of the Bcl-2 family. These proteins are

classified into this family based on limited sequence homology with the Bcl- 2homology domain

3 and carboxyl terminal transmembrane domain. BNip proteins were firstdiscovered based on

their interaction with the adenovirus E1B 19 kDa/Bcl-2 family protein and since then, their

roles in cell death pathways have been actively studied. However, the precise mechanisms by

which the BNip proteins induce apoptosis and/or necrosis remain to be determined.

Caspase7

The described roles of caspase-7 in apoptosis and inflammation suggest that interfering with

caspase-7 activation may prove beneficial in conditions where excessive cell death and/or

inflammation contribute to disease. Therapeutic inhibition can be achieved with synthetic

inhibitors or through targeted delivery of natural caspase inhibitors such as XIAP and the

baculoviral caspase inhibitor p35. Caspase-7 inhibition seems especially warranted in

neurodegenerative disorders such as Alzheimer’s disease and Huntington’s disease, where

increased caspase-7 expression correlates with excessive neuronal cell death. Another

potentially promising application is the prevention of lymphocyte cell death in sepsis. Extensive

leukocyte apoptosis is commonly observed in sepsis patients and was suggested tocontribute

to immune suppression and lethality). Synthetic caspase inhibitors and overexpression of the

anti-apoptotic protein Bcl-2 have already shown promising results in experimental sepsis

models). In addition to the potential roles of caspase-7 in sepsis and neurodegenerative

disorders, single nucleotide polymorphisms (SNPs) in the caspase-7 genehave been linked with

rheumatoid arthritis (SNP rs2227309; K249R mutation) Insulin- Dependent Diabetes Mellitus

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Gonen, C. (2024). PMA Induction to Prostate Cancer Cell Lines: DU145 and LNCaP. British Journal of Healthcare and Medical Research, Vol - 11(5).

86-94.

URL: http://dx.doi.org/10.14738/bjhmr.115.17644.

(SNP rs144692; D251E mutation) Additional studies are required to extend these promising

findings and to unravel the mechanisms by which the resulting missense mutations in caspase- 7 trigger disease Caspase 9.

Caspase 9 (also known as ICE-LAP6, or mch6) is considered to be a caspase in the upstream of

apoptotic signal transduction. When mitochondria release cytochrome c, Caspase 9 can form

complex with cytochrome c and Apaf1, and be activated at the same time. Activated Caspase 9

can activate Caspase 3 which is the key enzyme of cell apoptosis, thereby promoting subsequent

apoptotic signals. Caspase 9 exists in the form of prozyme in the normal state and has no

activity. However, Caspase 9 is activated in the apoptotic stage and participates in the apoptotic

process. This kit is used to conjugate Caspase 9 sequence-specificpeptides acetyl-Leu-Glu-His- Asp p-nitroanilide (Ac-LEHD-pNA) to yellow group p- nitroaniline (pNA)

Many of the roles played by the tumor suppressor in restraining cancer initiation and

progression are well established. These include the ability of to induce cell-cycle arrest, DNA

repair, senescence and apoptosis One of the hallmarks of human cancers is the intrinsic or

acquired resistance to apoptosis. Evasion of apoptosis can be part of a cellular stress response

to ensure the cell’s survival upon exposure to stress stimuli. There are two major apoptosis

signaling pathways, that is, the dead receptor (extrinsic) pathway and the mitochondrial

(intrinsic) pathway]. Under most circumstances, activation of either pathway eventually leads

to proteolytic cleavage and thus activation of caspases, a family of cysteine proteases that act

as common dead effector molecules. Accordingly, caspases are responsible for many of the

biochemical and morphological hallmarks of apoptotic cell dead by cleaving a range of

substrates in the cytoplasm or nucleus Cytochrome c has been implicated in the redox

regulation of apoptosis. Once cytochrome c is released from mitochondria into the cytosol, it

triggers the formation of the cytochrome c/Apaf-1/Caspase-9-containing apoptosome, which

in turn lead to activation of caspase-9 and downstream effector caspases There is recent

evidence that also the redox state of cytochrome c is involved in the regulation of apoptosis. To

this end, the oxidized form of cytochrome c (Fe(3+)) has been reported to induce caspase

activation via the apoptosome, while the reduced form of cytochrome c (Fe(2+)) is unable to do

so Response elements of prostate specific antigen (PSA) and NFkB are located at AR promoter

region and suggest that NFkB may affect AR expression.

Statistical Analysis

All the illustrated results represent one of at least three independent experiments withsimilar

outcomes.

Acknowledgement

This work was granted by The Scientific and Technological Research Council of Turkey

(TUBITAK) to CGK [Grant no: 106S295]; The Turkish Academy of Sciences (TUBA) to CGK

[GEBIP-2007].

Experimental Procedures Cell Culture

Cell lines were cultured in DMEM (GIBCO, USA) or RPMI 1640 (GIBCO) with 5% and 10% fetal

bovine serum for DU145 and LNCaP cells, respectively. 1% L-glutamine and 1U/ml of each

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penicillin/ streptomycin was used. Cells were incubated at 37°C and 5% CO2in a humidified

atmosphere.

TABLE 1: Primers for RT-PCR amplification

GeneBank/

Symbol

Description Gen Name Primers

NM_004322

BAD

BCL2-antagonist of cell

death

BBC2/BCL2L8 Forward

Reverse

AGGATCCGTGCTGTCTCCTTTG

CAAAACTTCCGATGGGACCAAG

NM_001188 BCL2-antagonist

/killer 1

BAK/BCL2L7 Forward GGGTGTAGATGGGGGAACTGTG

BAK1 Reverse AAGACCCTAGGCTGTGCCCAAT

NM_138578 BCL2-like 1 BCL-X/BCL-XL Forward GTGTGAGGAGCTGCTGGCTTG

BCL2L1 Reverse AGCATCAGGCCGTCCAATCTC

NM_001205

BNIP1

BCL2/adenovirusE1B 19kDa

interacting

protein 1

NIP1/TRG-8 Forward

Reverse

CAGGTTGGATGGAACACAGTGC

ATCCCAATGCCAGACCTTCCTC

NM_032982

CASP2

Caspase 2,

apoptosisrelated cysteine

protease

CASP-2/ICH-1L Forward

Reverse

TCTCCCATGGTCCCTAGCAAAA

AAGGCTCACAAACCACCCAAAC

NM_001227 Caspase 7,

apoptosisrelated cysteine

protease

CMH-1/ICE-LAP3 Forward AAGTGAGGAAGAGTTTATGGCAAA

CASP7 Reverse CCATCTTGAAAACAAAGTGCCAAA

NM_001229

CASP9

Caspase 9, apoptosisrelated

cysteine protease

APAF-3/APAF3 Forward

Reverse

TCCTGAGTGGTGCCAAACAAAA

AGTGGTTGTCAGGCGAGGAAAG

NM_005157

ABL1

V-abl Abelson murine

leukemiaviral oncogene

homolog 1

ABL/C-ABL Forward

Reverse

GGCCTTGAAGACAGAGCAAAGC

GGAAGGGACCAGTACCTCATGG

NM_005163

AKT1

V-akt murine thymoma viral

oncogene

homolog 1

PKB/PRKBA Forward

Reverse

TCCCCCTCAGATGATCTCTCCA

CGGAAAGGTTAAGCGTCGAAAA

NM_005427 Tumor proteinp73 P73 Forward AGCAGCCCATCAAGGAGGAGTT

TP73 Reverse TCCTGAGGCAGTTTTGGACACA

NM_000546

TP53

Tumor protein p53

(LiFraumeni

syndrome)

CYS51STOP/P53 Forward

Reverse

AGATGGGGTCTCACAGTGTTGC

ATGTTGACCCTTCCAGCTCCAC

NM_078467

P21

Homo sapiens

cyclindependent kinase

inhibitor

1A

CDKN1A Forward

Reverse

GGCAGACCAGCATGACAGATT

GCGGCCAGGGTATGTACATGA

NM_002392

MDM2

Homo sapiens Mdm2,

transformed 3T3cell double

minute 2

HDMX/MGC71221 Forward

Reverse

GGGTTCGCACCATTCTCCTG

GGCAGATGACTGTAGGCCAAGC

NM_016335 Homo sapiens

proline

PIG6/HSPOX2 Forward TTTTTCACCCCACACTTGCAGA

TGTCCCAGGCAGGTATCAGGTT

PRODH dehydrogenase

(oxidase) 1

Reverse

NM_001101 Homo sapiens actin, beta PS1TP5BP1, beta- actin

Forward CAATGTGGCCGAGGACTTTGAT

ACTB Reverse AGTGGGGTGGCTTTTAGGATGG

NM_002046

GAPDH

Homo sapiens

glyceraldehyde 3-phosphate

dehydrogenase

G3PD, GAPD Forward

Reverse

CATTGCCCTCAACGACCACTTT

GGTGGTCCAGGGGTCTTACTCC

References

BRUCKHEIMER, E. M. and Kyprianou, N. Apoptosis in prostate carcinogenesis. A growthregulator and a

therapeutic target. Cell Tissue Res, 301(1), 153-62 (2000).