Expression and localization of endocrine gland-derived vascular endothelial growth factor (EG-VEGF) in human pancreas and pancreatic adenocarcinoma

Disulfidptosis-related genes serve as potential prognostic biomarkers and indicate tumor microenvironment characteristics and immunotherapy response in prostate cancer

Disulfidptosis, a newly identified programmed cell death pathway in prostate cancer (PCa), is closely associated with intracellular disulfide stress and glycolysis. This study aims to elucidate the roles of disulfidptosis-related genes (DRGs) in the pathogenesis and progression of PCa, with the goal of improving diagnostic and therapeutic approaches. We analyzed PCa datasets and normal tissue transcriptome data from TCGA, GEO, and MSKCC. Using consensus clustering analysis and LASSO regression, we developed a risk scoring model, which was validated in an independent cohort. The model's predictive accuracy was confirmed through Kaplan-Meier curves, receiver operating characteristic (ROC) curves, and nomograms. Additionally, we explored the relationship between the risk score and immune cell infiltration, and examined the tumor microenvironment and somatic mutations across different risk groups. We also investigated responses to immunotherapy and drug sensitivity. Our analysis identified two disulfidosis subtypes with significant differences in survival, immune environments, and treatment responses. According to our risk score, the high-risk group exhibited poorer progression-free survival (PFS) and higher tumor mutational burden (TMB), associated with increased immune suppression. Functional enrichment analysis linked high-risk features to key cancer pathways, including the IL-17 signaling pathway. Moreover, drug sensitivity analysis revealed varied responses to chemotherapy, suggesting the potential for disulfidosis-based personalized treatment strategies. Notably, we identified PROK1 as a crucial prognostic marker in PCa, with its reduced expression correlating with disease progression. In summary, our study comprehensively assessed the clinical implications of DRGs in PCa progression and prognosis, offering vital insights for tailored precision medicine approaches.

Therapeutic Potential of Targeting Prokineticin Receptors in Diseases

The prokineticins (PKs) were discovered approximately 20 years ago as small peptides inducing gut contractility. Today, they are established as angiogenic, anorectic, and proinflammatory cytokines, chemokines, hormones, and neuropeptides involved in variety of physiologic and pathophysiological pathways. Their altered expression or mutations implicated in several diseases make them a potential biomarker. Their G-protein coupled receptors, PKR1 and PKR2, have divergent roles that can be therapeutic target for treatment of cardiovascular, metabolic, and neural diseases as well as pain and cancer. This article reviews and summarizes our current knowledge of PK family functions from development of heart and brain to regulation of homeostasis in health and diseases. Finally, the review summarizes the established roles of the endogenous peptides, synthetic peptides and the selective ligands of PKR1 and PKR2, and nonpeptide orthostatic and allosteric modulator of the receptors in preclinical disease models. The present review emphasizes the ambiguous aspects and gaps in our knowledge of functions of PKR ligands and elucidates future perspectives for PK research. SIGNIFICANCE STATEMENT: This review provides an in-depth view of the prokineticin family and PK receptors that can be active without their endogenous ligand and exhibits "constitutive" activity in diseases. Their non- peptide ligands display promising effects in several preclinical disease models. PKs can be the diagnostic biomarker of several diseases. A thorough understanding of the role of prokineticin family and their receptor types in health and diseases is critical to develop novel therapeutic strategies with safety concerns.

Prokineticin-1 induces normal lymphangiogenic activity and is involved in lymphangiogenesis and lymph node metastasis in colorectal cancer

Background: Prokineticin family correlates with important roles in several biological processes, including homeostasis. We discovered novel functions of prokineticin1 (PROK1) in lymphangiogenesis and lymphnode metastasis in colorectal cancer.

Materials and Methods: We examined changes in the number of lymphatic endothelial cells after PROK1 stimulation. PROK1 protein was stimulated with subcutaneously implanted in mice. Also a high-PROK1-expressing colorectal cancer cell line and anti-PROK1 antibody(Ab) were subcutaneously implanted in mice, and then examine lymphangiogenesis. PROK1 expression and the number of lymph vessels were examined in the primary lesion of 391 patients whose colorectal tumors had been resected.

Results: When PROK1 was used as a stimulus, the number of lymphatic cells increased compared to unstimulated cells. And the number of lymph vessels in the skin of mice increased compared to mice implanted without PROK1. The number of lymph vessels in the primary tumor tissue increased when PROK1 was highly expressed compared to cases with non-detectable PROK1 expression. When PROK1 was expressed in human colorectal tumors, the rate of lymphnode metastasis was significantly higher than that in cases with non-detectable PROK1 expression.

Conclusions: PROK1 is a lymphangiogenic factor involved in the formation of new lymph vessels and lymphnode metastasis in human colorectal cancer.

VEGF, VEGF165b and EG-VEGF expression is specifically related with hormone profile in pituitary adenomas

Vascular endothelial growth factor (VEGF), its inhibitory splice variant, VEGF165b and Endocrine Gland derived VEGF (EG-VEGF) have a controversial role in pituitary gland. We aim to study VEGF, VEGF165b and EG-VEGF expression in pituitary adenomas. A significant correlation was found between growth hormone (GH) and VEGF secretion (P=0.024). For prolactinomas, VEGF and prolactin expression, had a P-value of 0.02 for Kendall coefficient and a P-value of 0.043 for the Spearman coefficient. VEGF-mRNA amplification was detected in both tumor cells and folliculostellate cells. VEGF165b was positive in 16.66% of pituitary adenomas. EG-VEGF was significantly correlated with prolactin (P=0.025) and luteinizing hormone (P=0.028). Our data strongly support VEGF, VEGF165b and EG-VEGF as important players of pituitary adenomas tumorigenesis. Particular hormonal milieu heterogeneity, special vascular network with an unusual reactivity to tumor growth correlated with variability of VEGF, VEGF165b and EG-VEGF secretion may stratify pituitary adenomas in several molecular groups with a direct impact on therapy and prognosis.

EG-VEGF silencing inhibits cell proliferation and promotes cell apoptosis in pancreatic carcinoma via PI3K/AKT/mTOR signaling pathway

OBJECTIVE

Pancreatic carcinoma (PC), one of the most prevalent and malignant tumors, has a poor prognosis and a high mortality rate. EG-VEGF, a vascular endothelial growth factor from endocrine glands, also termed as PROK1, has a high positive expression rate in PC tissues and is involved in the pathogenesis of various tumors. However, the expression and potential role of EG-VEGF in PC has not been thoroughly explored. The aim of this study was to better clarify the expression and potential role of EG-VEGF in pancreatic carcinoma.

METHODS

Immunohistochemical staining, western blotting, and RT-qPCR analysis were performed to detect the EG-VEGF level in PC tissues and cells. Subsequently, two short hairpin RNA (shRNA) lentiviral expression vector, shPROK1-1/shPROK1-2, were transfected into PANC-1 and BxPC-3 PC cell lines. MTT assay was used to determine cell proliferation. Meanwhile, flow cytometry assay was conducted to measure cell cycle and cell apoptosis. The protein levels of PI3K/AKT/mTOR pathway-related genes were also determined by western blotting.

RESULTS

EG-VEGF was aberrantly expressed in PC samples, as compared with paracancerous samples. Knockdown of PROK1 notably decreased the protein level of EG-VEGF, indicating a successful downregulation model of EG-VEGF. EG-VEGF silencing remarkably attenuated cell proliferation, while also induced G0/G1 arrest and magnified the extent of cell apoptosis. Further, EG-VEGF knockdown significantly inhibited PI3K/AKT/mTOR signaling pathway by downregulating p-PI3K, p-AKT, and p-mTOR levels.

CONCLUSION

This study identified the high-expression of EG-VEGF in pancreatic carcinoma tissues and cells, and demonstrated that EG-VEGF silencing inhibits the proliferation of PC cells and promotes apoptosis via regulating PI3K/AKT/mTOR pathway. Thus, EG-VEGF may become an essential target for the therapy of pancreatic cancer in the future.

Endocrine Gland-Derived Vascular Endothelial Growth Factor/Prokineticin-1 in Cancer Development and Tumor Angiogenesis

A lot of data suggests endocrine gland-derived vascular endothelial growth factor (EG-VEGF) to be restricted to endocrine glands and to some endocrine-dependent organs. Many evidences show that EG-VEGF stimulates angiogenesis and cell proliferation, although it is not a member of the VEGF family. At the time, a lot of data regarding the role of this growth factor in normal development are available. However, controversial results have been published in the case of pathological conditions and particularly in malignant tumors. Thus, our present paper has been focused on the role of EG-VEGF in normal tissues and various malignant tumors and their angiogenic processes.

Expression of prokineticin-receptor2(PK-R2) is a new prognostic factor in human colorectal cancer

The increased invasiveness of colorectal cancer cells is important for progression and metastasis to the surrounding organs. According to recent molecular biological studies, signaling through transmembrane Prokineticin-Receptor2(PK-R2) is likely involved in the ability of tumor cell to invade. However, no studies have evaluated the relationship between PK-R2 expression, ability of cancer to invade/metastasize, and patient prognosis in cases of resected colorectal cancer. Accordingly, we have examined these factors in the present study.

Immunohistochemical staining was performed to detect PK-R2 in the primary lesion and adjacent normal large intestine mucosa of 324 colorectal cancer patients who underwent resection surgery at our department. Additionally, we conducted clinicopathologic examinations and analyzed patient prognoses with the Kaplan-Meier method. Further, multivariate analysis was conducted using a cox-proportional hazard model.

PK-R2 expression was observed on the cellular membrane of the primary lesion in 147 of 324 cases (45.3%) of human colorectal cancer. PK-R2 expression was associated with a higher incidence of vascular invasion, lymph node metastasis, hepatic metastasis, and hematogenous metastasis. Further, prevalence of PK-R2 expression increased as tumor stage increased. In stage III curative resection cases, where recurrence is the most serious problem, cases that expressed PK-R2 had a significantly lower 5-year survival rate (82.1% versus 66.8%) and higher recurrence compared to those cases with no PK-R2 expression. In the multivariate analysis for prognosis, PK-R2 expression was found to be an independent factor(ratio2.621).

PK-R2 expression could be one of the new prognostic factors in human colorectal cancer.

Role of Endocrine Gland-Derived Vascular Endothelial Growth Factor (EG-VEGF) and Its Receptors in Adrenocortical Tumors

Angiogenesis is essential for tumor growth and metastasis. Endocrine gland-derived vascular endothelial growth factor (EG-VEGF) is an angiogenic factor predominantly expressed in steroidogenic organs like the adrenal gland, ovary, testes, and placenta. EG-VEGF has antiapoptotic, mitogenic, and chemoattractive properties mediated via the two G protein-coupled receptors prokineticin receptor 1 (PKR1) and prokineticin receptor 2 (PKR2). We investigated the expression of EG-VEGF and its receptors in a large number of normal adrenal glands (NAG), adrenocortical adenomas (ACA), and carcinomas (ACC) using real-time PCR (NAG, n = 12; ACA, n = 24; and ACC, n = 30) and immunohistochemistry (NAG, n = 9; ACA, n = 23; and ACC, n = 163) and evaluated its impact on patients’ survival. EG-VEGF, PKR1, and PKR2 mRNA and protein are expressed in NAG and the vast majority of ACA and ACC samples. The mean EG-VEGF mRNA expression was significantly lower in ACC (606.5 ± 77.1 copies) compared to NAG (4,043 ± 1,111) and cortisol-producing adenomas (CPA) (4,433 ± 2,378) (p < 0.01 and p < 0.05, respectively). However, cytoplasmic and nuclear EG-VEGF protein expression was either significantly higher or similar in ACC (H score 2.4 ± 0.05, p < 0.05 and 1.7 ± 0.08, n.s., respectively) compared to NAG (1.8 ± 0.14 and 1.7 ± 0.2). Nuclear protein expression of either EG-VEGF or PKR1 or both is predictive for a higher mortality compared to patients without nuclear expression (hazard ratio (HR) = 5.15; 95 % confidence interval (CI) = 1.24–21.36, n = 100, p = 0.02 independent of age, sex, and tumor stage). These findings suggest that EG-VEGF and its receptor PKR1 might play a role in the pathogenesis of adrenocortical tumors and could serve as prognostic markers for this rare malignant disease.

The prognosis was poorer in colorectal cancers that expressed both VEGF and PROK1 (No correlation coefficient between VEGF and PROK1)

The angiogenic proteins vascular endothelial growth factor (VEGF) and prokineticin1 (PROK1) proteins are considered important in colorectal cancer, the relationship between their simultaneous expression and prognosis was investigated in the present study.

VEGF and PROK1 expression in 620 primary human colorectal cancer lesions was confirmed via immunohistochemical staining with anti-VEGF and anti-PROK1 antibodies, and the correlation between the expression of these 2 proteins and recurrence/prognosis were investigated.

VEGF protein was expressed in 329 (53.1%) and PROK1 protein was expressed in 223 (36.0%). PROK1 and VEGF were simultaneously expressed in 116 (18.7%) of the 620 cases. The correlation coefficient between VEGF expression and PROK1 expression was r = 0.11, and therefore correlation was not observed. Clinical pathology revealed that substantially lymphnode matastasis, hematogenous metastasis, or TMN advanced-stageIV was significantly more prevalent in cases that expressed both VEGF and PROK1 than in the cases negative for both proteins or those positive for only 1 of the proteins.

Also the cases positive for both proteins exhibited the worst recurrence and prognosis. In the Cox proportional hazards model, VEGF and PROK1 expression was an independent prognostic factor.

The prognosis was poorer in colorectal cancers that expressed both PROK1 and VEGF relative to the cases that expressed only 1 protein, and the expression of both proteins was found to be an independent prognostic factor.

The anti-tumor effect is enhanced by simultaneously targeting VEGF and PROK1 in colorectal cancer

Hematogenous metastasis, mainly hepatic metastasis, is a frequent metastatic mode in colorectal cancer involving angiogenic growth factors. Two angiogenic growth factors, in particular, Vascular endothelial growth factor (VEGF) and Prokineticin1(PROK1), are considered to have an important role in hematogenous metastasis of colorectal cancer. Accordingly, we report our findings on the importance of the anti-tumor efffect by inhibiting these two factors in human colorectal cancer.When the culture fluid of Colorectal cancer cell lines(DLD-1, HCT116, and LoVo) with high levels of VEGF/PROK1 expression was injected subcutaneously into mice, the culture fluid increased subcutaneous angiogenesis. But when both anti-PROK1 and anti-VEGF antibodies were present in the culture fluid, the length and size of the blood vessels were reduced compared with those seen in the fluid-only, anti-PROK1, and anti-VEGF controls. Also, tumor masses were produced in mice by subcutaneously embedding colorectal cancer cells with high levels VEGF/PROK1 expression. When both anti-PROK1 and anti-VEGF antibodies were simultaneously applied, tumor formation and peritumoral angiogenesis were strongly suppressed, compared with when either anti-PROK1 antibody or anti-VEGF antibody was applied alone.Simultaneous targeting of both angiogenic growth factors (VEGF/PROK1) may prove more useful in colorectal cancer.

Endocrine gland‑derived vascular endothelial growth factor modulates proliferation, apoptosis and migration in pancreatic cancer cells

Endocrine gland‑derived vascular endothelial growth factor (EG‑VEGF) is a newly cloned factor that selectively acts on the endothelium of endocrine gland cells. EG‑VEGF was previously identified as an important cytokine, involved in the modulation of apoptosis in pancreatic cancer cell lines. The present study examined the effects of EG‑VEGF proliferation and migration, in pancreatic cancer cells. To determine the potential for EG‑VEGF as a therapeutic target for pancreatic cancer, the expression of EG‑VEGF were measured in pancreatic cancer tissue, and the association between its expression and the clinicopathological characteristics of the pancreatic cancer patients was determined. The results of the present study suggest that EG‑VEGF may act as a novel tumor gene in pancreatic cancer. EG‑VEGF was rarely expressed in the normal pancreatic tissue, but was highly expressed in the pancreatic cancer tissue. These data suggest that EG‑VEGF may be a cancer‑specific, and possibly tissue‑specific, survival factor in the pancreas. In the Mia PaCa‑2 pancreatic cancer cell line, EG‑VEGF was shown to promote proliferation and cellular invasion, and modulate the phosphorylation of mitogen‑activated protein kinase, a modulator for the malignant phenotype.

Prokineticin 1 protein expression is a useful new prognostic factor for human sporadic colorectal cancer

BACKGROUND

Hematogenous metastasis, regarded as closely related to angiogenic growth factors, is associated with colorectal cancer prognosis. The angiogenic growth factor prokineticin 1 (PROK1) has been cloned from endocrine cells. However, its protein expression in human malignant tumors has not been studied. The current study established the anti-PROK1 monoclonal antibody (mAb) and examined the relationship between the expression of PROK1 protein and human colorectal cancer.

METHODS

The expression of PROK1 protein was assessed in 620 resected sporadic colorectal cancer tissue samples by immunohistochemical staining with in-house-developed human PROK1 mAb to investigate the relationship of PROK1 expression to clinicopathologic factors, recurrence, and survival rate and to evaluate its prognostic significance.

RESULTS

The expression of PROK1 protein was detected in 36 % (223/620) of human primary colorectal cancer lesions but no in the healthy mucosa adjacent to the colorectal cancer lesions. According to the clinicopathologic examinations, the frequency of positive PROK1 expression was significantly higher in cases with serosal invasion, lymphatic invasion, venous invasion, lymph node metastasis, liver metastasis, hematogenous metastasis, and higher stage disease. The recurrence rate and prognosis for patients with PROK1 expression-positive lesions were significantly worse. In the Cox proportional hazard model, PROK1 expression was an independent prognostic factor.

CONCLUSIONS

The expression of PROK1 protein was identified for the first time as a new prognostic factor in colorectal cancer.

Anti-prokineticin1 (PROK1) monoclonal antibody suppresses angiogenesis and tumor growth in colorectal cancer

BACKGROUND

The prokineticin1 (PROK1) gene has been cloned as an angiogenic growth factor from endocrine gland cells. However, we have not known about potentials of anti-PROK1 monoclonal antibody in human cancers. Here we investigated how the anti-PROK1 monoclonal antibody (mAb; established by our department) would affect the high-PROK1-expressing colorectal cancer (CRC) cells in vitro and vivo.

METHODS

We confirmed PROK1 protein expression in the CRC cells by performing immunohistochemical staining and measured the amount of soluble PROK1 protein. Next, we mixed the CRC cell culture fluid with the anti-PROK1mAb to examine angiogenic activity in vitro and in vivo. Additionally, we investigated whether the anti-PROK1mAb would affect the tumor-forming capability of high PROK1-expressing CRC cells implanted into mice.

RESULTS

PROK1 protein expression was confirmed in 3 CRC cell lines, and soluble PROK1 protein was also confirmed in the CRC cell culture fluid. The culture fluid increased angiogenesis in vitro and vivo, whereas the anti-PROK1mAb suppressed angiogenesis. Subcutaneous tumor formation and tumor angiogenesis in mice were suppressed by the anti-PROK1mAb treatment. The anti-PROK1mAb significantly suppressed the number of CD31 stained cells in mice.

CONCLUSIONS

The in vitro and vivo experimental system indicated that the anti-PROK1mAb could suppress angiogenesis and tumor growth in the CRC strains.

Prokineticins and Merkel cell polyomavirus infection in Merkel cell carcinoma

BACKGROUND

Prokineticin-1 (PROK1) and prokineticin-2 (PROK2) are chemokine-like proteins that may influence cancer growth by regulating host defence and angiogenesis. Their significance in viral infection-associated cancer is incompletely understood. We studied prokineticins in Merkel cell carcinoma (MCC), a skin cancer linked with Merkel cell polyomavirus (MCPyV) infection.

METHODS

Carcinoma cell expression of PROK1 and PROK2 and their receptors (PROKR1 and PROKR2) was investigated with immunohistochemistry, and tumour PROK1 and PROK2 mRNA content with quantitative PCR from 98 MCCs. Subsets of tumour infiltrating leukocytes were identified using immunohistochemistry.

RESULTS

Merkel cell polyomavirus-positive MCCs had higher than the median PROK2 mRNA content, whereas MCPyV-negative MCCs contained frequently PROK1 mRNA. Cancers with high tumour PROK2 mRNA content had high counts of tumour infiltrating macrophages (CD68+ and CD163+ cells). Patients with higher than the median PROK2 mRNA content had 44.9% 5-year survival compared with 23.5% among those with a smaller content (hazard ratio (HR): 0.53; 95% confidence interval (CI): 0.34-0.84; P=0.005), whereas the presence of PROK1 mRNA in tumour was associated with unfavourable survival (P=0.052).

CONCLUSIONS

The results suggest that prokineticins are associated with MCPyV infection and participate in regulation of the immune response in MCC, and may influence outcome of MCC patients.

Evidence of an intracellular angiotensin-generating system and non-AT1, non-AT2 binding site in a human pancreatic cell line

OBJECTIVES

To assess the presence of a local angiotensin-generating systems (LAGS) and its participation in tumor growth in the human pancreatic cancer derived cell line Capan-1.

METHODS

Capan-1 cells were cultured in Dulbecco modified Eagle medium, and angiotensin I was assayed by radioimmunoassay and angiotensin II and vascular endothelial growth factor were assayed by enzyme-linked immunosorbent assay in the supernatant. Immunohistochemistry and reverse transcription-polymerase chain reaction were performed for the expression of AT1 and AT2 receptors. Angiotensin II binding assays and blockade were studied.

RESULTS

High levels of both angiotensins I and II were found in Capan-1 cells, although neither angiotensin I nor angiotensin II was detected in the cell culture supernatant. Reverse transcription-polymerase chain reaction and immunocytochemistry revealed that Capan-1 cells do not express AT1 and AT2 receptors; however, specific binding to the cell membrane was identified for angiotensin II. Neither exogenous angiotensin II nor Dup753 (specific AT1 receptor blocker) affected Capan-1 cells' proliferation or vascular endothelial growth factor secretion.

CONCLUSIONS

Detection of both angiotensin I and angiotensin II along with specific binding of angiotensin II in Capan-1 cells provides evidence of the existence of a LAGS that operates in an intracrine manner. Intracellular angiotensin II may play a role in the aggressiveness of pancreatic cancer and is a possible target for therapeutic agents.

Sex steroids effects on the endocrine pancreas

The endocrine pancreas is central in the physiopathology of diabetes mellitus. Nutrients and hormones control endocrine pancreatic function and the secretion of insulin and other pancreatic islet hormones. Although the pancreas is not usually considered as a target of steroids, increasing evidence indicates that sex steroid hormones modify pancreatic islet function. The biological effects of steroid hormones are transduced by both, classical and non-classical steroid receptors that in turn produce slow genomic and rapid non-genomic responses. In this review, we focused on the effects of sex steroid hormones on endocrine pancreatic function, with special emphasis in animal studies.

Endocrine glands-derived vascular endothelial growth factor protects pancreatic cancer cells from apoptosis via upregulation of the myeloid cell leukemia-1 protein

Endocrine glands-derived vascular endothelial growth factor (EG-VEGF, also termed as Prok1)--a novel cytokine that selectively acts on the endothelial cells of endocrine glands--was recently reported to be involved in the regulation of tumor cell growth and survival. However, its roles in the regulation of pancreatic cancer progression remain unclear. In this report, we investigated the suppressive effects of EG-VEGF on pancreatic cancer cell apoptosis and the relevant mechanisms. By using reverse-transcriptase polymerase chain reaction (RT-PCR) we found that the Mia PaCa II cells of the pancreatic cancer cell line express the mRNAs of both EG-VEGF (Prok1) and its receptors. EG-VEGF protects pancreatic cancer cells from apoptosis through upregulation of myeloid cell leukemia-1 (Mcl-1), an anti-apoptotic protein of the bcl-2 family. Treatment of pancreatic cancer cells with EG-VEGF results in the rapid phosphorylation of mitogen-activated protein kinase (MAPK), STAT3, and AKT, which are involved in the upregulation of Mcl-1 expression. EG-VEGF (Prok1) protects Mia PaCa II cells from apoptosis through G protein-coupled receptor (GPR)-induced activation of multiple signal pathways, and hence can be a novel target for pancreatic cancer therapy.