• Journal of Radiopharmaceuticals and Molecular Probes
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• v.8 no.2
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• pp.129-137
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• 2022

Bombesin has a high binding affinity to gastrin-releasing peptide receptor (GRPR) and can be used as a targeting ligand in GRPR-related cancers. Because GRPR is overexpressed in prostate cancer, bombesin analogues have been investigated extensively for diagnosis and treatment of prostate cancer. In nuclear medicine, bombesin derivatives labeled with radiometals such as ^55/57Co, ⁶⁴Cu, ⁶⁸Ga, ^99mTc, and ¹⁷⁷Lu or radiohalogen such as ¹³¹I and ²¹¹At were developed as markers for early detection of tumors and theragnostic tool for cancer treatment. This review focuses on the introduction of bombesin-based radiopharmaceuticals that are studied in pre-clinical or clinical research.

• 한국생물공학회:학술대회논문집
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• 2005.04a
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• pp.510-510
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• 2005

• Journal of Radiation Industry
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• v.7 no.2_3
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• pp.127-134
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• 2013

Bombesin receptors are overexpressed in many kinds of human tumors. In particular, the gastrin releasing peptide receptor (GRPR) which is also called bombesin receptor subtype 2, has been identified in prostate cancer. In the present study, we developed a bombesin antagonist-based $^{177}Lu$-labeled peptide, $^{177}Lu$-DOTA-$Ala(SO_3H)$-Aminooctanoyl-Gln-Trp-Ala-Val-N methyl Gly-His-Statine-Leu-$NH_2$ (DOTA-sBBNA). DOTA-sBBNA was prepared using a solid phase synthesis method. It was labeled with $^{177}Lu$ by a high radiolabeling yield (>98%), and its Log P value was -2.05. The radiolabeled peptide was highly stable in serum incubation at $37^{\circ}C$ for 48 hr. A competitive displacement of $^{125}I-[Tyr^4]$-Bombesin on the PC-3 human prostate carcinoma cells revealed that the $IC_{50}$ value of the peptide was 6.76 nM indicating a highly nanomolar binding affinity for GRPR. These results suggest that $^{177}Lu$-DOTA-sBBNA can be a potential candidate for targeting prostate cancer, and further studies to evaluate its biological characteristics are needed.

• BMB Reports
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• v.50 no.12
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• pp.628-633
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• 2017

Gastrin-releasing peptide (GRP) has been reported to be implicated in the pathogenesis of inflammatory disorders. The migration and proliferation of vascular smooth muscle cells (VSMCs) are key components of vascular inflammation that leads to the development of atherosclerosis. The present study aimed to investigate the molecular effect of GRP on VSMC proliferation and migration. We report that GRP significantly enhanced the proliferation and migration of rat VSMCs. GRP increased mRNA and protein expression of matrix metalloproteinase-2 and -9 (MMP-2/9) in VSMCs. The induction of MMP-2/9 by GRP was regulated by the activation of the signal transducer and activator of transcription-3 (STAT3). In addition, STAT3-knockdown of VSMCs by siRNA or blockade of the GRP receptor inhibited GRP-induced migration of VSMCs. Taken together, our findings indicate that GRP promotes the migration of VSMCs through upregulation of MMP-2/9 via STAT3 activation.

• The Korean Journal of Physiology and Pharmacology
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• v.3 no.4
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• pp.427-432
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• 1999

Although importance of intrapancreatic neurons containing gastrin-releasing peptide (GRP) in control of exocrine secretion has been raised, the nature of GRP in the pancreas is unclear. Thus, the present study was undertaken to see distribution, content and molecular heterogeneity of immunoreactive GRP in the rat pancreas. Content of immunoreactive GRP in the rat pancreas was $2.99\;{\pm}\;0.66$ ng/g wet tissues determined by radioimmunoassay. Immunoreactive GRP was most abundantly expressed in the duodenal part among 3 parts of the pancreas; duodenal, body and splenic part. Vagotomy failed to change the content of immunoreactive GRP in the pancreas. Three distinct forms of immunoreactive GRP, very identical to GRP-27, bombesin-24 and neuromedin C, were observed in the rat pancreas by using reversed phase $C_{18}$ HPLC and Sephadex G-50 superfine column chromatography. Cell bodies of neurons containing immunoreactive GRP were scattered in pancreatic connective tissues and their nerve fibers innervated pancreatic acini and large ducts as determined by immunohistochemistry. The present results suggest that three distinct forms of GRP exist in intrapancreatic GRPergic neurons, which exert a stimulatory role in pancreatic exocrine secretion in rats.

• Journal of Radiation Industry
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• v.7 no.2_3
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• pp.191-200
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• 2013

In this study, a novel bombesin (BBN) analogues, DOTA-Ala($SO_3H$)-4 aminobenzoyl-Gln-Trp-Ala-Val-Gly-His-Leu-Met-$NH_2$ (DOTA-sBBN) and DOTA-Lys(glucose)-4 aminobenzoyl-Gln-Trp-Ala-Val-Gly-His-Leu-Met-$NH_2$ (DOTA-gluBBN), were synthesized and radiolabeled, and their binding affinities were evaluated. Peptides were prepared by a solid phase synthesis method and their purities were over 98%. DOTA is the chelating agent for $^{177}Lu$-labeling, and the DOTA-conjugated peptides were radiolabeled with $^{177}Lu$ by a high radiolabeling yield (>98%). The Log P values of DOTA-sBBN and DOTA-gluBBN were -2.20 and -2.79, respectively. 50.41% of $^{177}Lu$-DOTA-sBBN and 72.97% of $^{177}Lu$-DOTA-gluBBN were left undegraded by the serum incubation at $37^{\circ}C$ for 48 hr. A competitive displacement of $^{125}I-[Tyr^4]$-BBN on the PC-3 human prostate carcinoma cells revealed that 50% inhibitory concentration ($IC_{50}$) were 1.46 nM of DOTA-sBBN and 4.67 nM of DOTA-gluBBN indicating a highly nanomolar binding affinity for GRPR. Therefore, it is concluded that $^{177}Lu$-DOTA-sBBN and $^{177}Lu$-DOTA-gluBBN can be potential candidates as a targeting modality for the Gastrin-releasing peptide receptor (GRPR)-over-expressing tumors, and further studies to evaluate their biological and pharmacological characteristics are needed.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.12
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• pp.5179-5183
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• 2016

Background: Prior series investigated the expression of prepro-gastrin releasing peptide (prepro-GRP) in the peripheral blood of lung cancer patients. Our aim was to assess any prepro-GRP role as a prognostic factor for small cell lung cancer (SCLC) and NSCLC and correlations with clinical presentation and treatment outcome. Methods: A prospective study was conducted during the time period from the beginning of January 2012 till the end of January 2014. Prepro-GRP expression was analysed using a nested RT-PCR assay in peripheral blood of 62 untreated lung cancer patients attending the National Cancer Institute (NCI), Cairo University, and 30 age and sex matched healthy volunteers. Results: Among the 62 lung cancer cases, there were 24 (38.7%) SCLC, and 38 (61.3%) NSCLC (10 squamous cell carcinomas, 12 adenocarcinomas, 11 large cell carcinomas, 4 undifferentiated carcinomas, and 1 adenosquamous carcinoma). Twenty six patients (41.9%) were prepro-GRP positive. Prepro-GRP expression was higher (58.3%) among SCLC patients compared to NSCLC (squamous cell carcinoma (15.4%), large cell carcinoma (36.4%), and adenocarcinoma (25%)). Mean OS among prepro-GRP negative cases was longer than that among preprogastrin positive cases (17.6 vs 14.9 months). The mean PFS durations among preprogastrin negative versus positive cases were 7.7 vs 4.6 months (p= 0.041). No difference in response to chemotherapy was identified between the groups (p=0.983). Conclusion: Prepro-GRP is suggested to be a useful prognostic marker for lung cancer patients, especially with the fast- growing, bad prognostic SCLC type. More studies should aim at detailed understanding of the mechanisms of prepro-GRP action and its use in monitoring the response to treatment in a larger cohort.

• Biomolecules & Therapeutics
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• v.18 no.3
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• pp.246-256
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• 2010

Atopic dermatitis is a common skin disease affecting up to 10% of children and approximately 2% of adults. Atopic dermatitis exhibits four major symptoms, including intense itching, dry skin, redness and exudation. The "itch-scratch-itch" cycle is one of the major features in atopic dermatitis. The pathophysiology and neurobiology of pruritus is unclear. Currently there are no single and universally effective pharmacological antipruritic drugs for treatment of atopic dermatitis. Thus, controlling of itch is a very important unmet need in patients suffering from atopic dermatitis. This article will update progress during the past 10 years of research in the field of pruritus of atopic dermatitis, focusing on aspects of pruritogens (including inflammatory lipids, histamine, serotonin, proteinases, proteinase-activating receptors, neurotransmitters, neuropeptides, and opioid peptides), antipruritic therapies, and emerging new targets. Based on recent progress, researchers expect to identify exciting possibilities for improved treatments and to develop new antipruritic drugs acting through novel targets, such as histamine H4 receptor, gastrin-releasing peptide receptor, MrgprA3, thromboxane A2 receptor and the putative SPC receptor.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.20
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• pp.9039-9043
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• 2014

There is a continuing need for innovative alternative therapies for liver cancer. DNA vaccines for hormone/growth factor immune deprivation represent a feasible and attractive approach for cancer treatment. We reported a preventive effect of a DNA vaccine based on six copies of the B cell epitope GRP18-27 with optimized adjuvants against H22 hepatocarcinoma. Vaccination with pCR3.1-VS-HSP65-TP-GRP6-M2 (vaccine) elicited much higher level of anti-GRP antibodies and proved efficacious in preventing growth of transplanted hepatocarcinoma cells. The tumor size and weight were significantly lower (p<0.05) in the vaccine subgroup than in the control pCR3.1-VS-TP-HSP65-TP-GRP6, pCR3.1-VS-TP-HSP65-TP-M2 or saline subgroups. In addition, significant reduction of tumor-induced angiogenesis associated with intradermal tumors of H22 cells was observed. These potent effects may open ways towards the development of new immunotherapeutic approaches in the treatment of liver cancer.

• The Korean Journal of Physiology
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• v.28 no.1
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• pp.91-97
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• 1994

In order to produce a specific bombesin antiserum far very sensitive radioimmunoassay, synthetic $[lys^3]-bombesin$ conjugated to bovine serum albumin was subcutaneously injected into guinea pigs. The conjugation was performed using either carbodiimide or gIutaraldehyde as a coupling agent. The antisera were characterized by analysis of Scatchard and Sips plots. The antiserum LBE 2G/2 raised by repeat injection of the immunogen conjugated with carbodiimide showed the titer of 1 : 188,000, very low cross-reactivity to bombesin-like peptides except bombesin, with high affinity constant $(1.64{\times}10^{11}\;M^{-1})$ and high heterogeneity index (0.91). The antiserum LBG 1G/2 produced by repeat injection of the immunogen conjugated with glutaraldehyde possessed the titer of 1 : 43,000, high cross-reactivity to some bombesin-like peptides, high affinity constant $(1.19{\times}10^{11}\;M^{-1})$ and high heterogeneity index (0.79). These results indicate that the antiserum LBE 2G/2 is specific only to bombesin and that the antiserum LBG IG/2 binds to some bombesin-like peptides such as alytesin, gastrin releasing peptide and neuromedin C. The antiserum LBE 2G/2 is sufficient for the very sensitive radioimmunoassay of bombesin.