[Clinical characteristics and CYP17A1 gene mutation analysis in patients with 17α-hydroxylase/17, 20-lyase deficiency and testicular tumor]

The 17α-hydroxylase/17, 20-lyase deficiency (17-OHD) is a rare disease. The clinical characteristics and gene mutation of 2 late-diagnosed 17-OHD patients with testicular tumor admitted to our hospital from March 2018 to February 2019 were analyzed retrospectively. The two 17-OHD patients were female (46, XY). Laparoscopic abdominal exploration found undeveloped testicles in grey-yellow or grey-red in the groin and iliac fossa. The testicles were removed and showed malignancy in pathology study. Sequencing of the CYP17A1 gene identified c.1247G>A/c.1427T>C and c.985_987delTACinsAA/c.1306G>A complex heterozygous mutations. Taking together, the possibility of 17-OHD should be considered in patients with hypertension, hypokalemia, adrenal adenomatoid hyperplasia together with 46, XY gonadal dysplasia, so as to make early diagnosis and treatment, and avoid dysplastic testicular turning to malignancy.

[Establishment of cut-off value of serum pro-gastrin-releasing peptide for diagnosis of small cell lung cancer and evaluation on the clinical diagnosis efficiency]

Objective: To determine critical reference value (cut-off value) of serum pro-gastrin-releasing peptide (ProGRP) and neuron specific enolase(NSE) in the diagnosis of small cell lung cancer(SCLC). To evaluate the clinical significance of serum levels of ProGRP and NSE in diagnosis and differential diagnosis in SCLC. Methods: Three hundred and fifty-two SCLC patients, 163 non small cell lung cancer(NSCLC)patients , 193 benign pulmonary disease patients and 140 healthy people visiting in National Cancer Hospital were analyzed retrospectively from January 2014 to July 2017.The levels of serum ProGRP and NSE of people were determined using electrochemiluminescent immunoassay respectively . Reference value ranges of the makers were determined by using the method of ROC curves. Results: In NSCLC group, benign lung disease group, healthy control group and mixed group (NSCLC+ lung benign diseases+ healthy control group) as a reference, the cut-off values were 58.3, 62.3, 57.8, 61.3 ng/L. In the diagnosis and differential diagnosis of SCLC and NSCLC, benign lung diseases, healthy controls and mixed group, AUC of ProGRP was 0.940 (0.919-0.961), 0.941 (0.921-0.960), 0.959 (0.944-0.975), 0.946 (0.928-0.963) respectively. The sensitivities of ProGRP were 86.4%, 84.9%, 86.4% and 84.7% respectively. The specificities of ProGRP were 95.7%, 96.9%, 99.3%, 98% respectively. In all groups the Youden's index of ProGRP and NSE were 0.821 vs 0.612, 0.818 vs 0.674, 0.857 vs 0.810, 0.827 vs 0.674. In healthy controls, no statistically significant difference was found between ProGRP and NSE (P>0.05) in the diagnosis of AUC. However, in the remaining 3 groups, the ProGRP diagnosis of AUC was significantly greater than that of NSE (P<0.01). Compared with single marker detection, the sensitivity of combined detection of ProGRP and NSE in diagnosis of SCLC increased to 95.5%, 94%, 96.6% and 94% in each group. There was no significant difference between ProGRP and ProGRP+ NSE in the diagnosis of AUC when compared with the NSCLC group and the mixed group (P>0.05). However, when combined with a healthy control group and a benign lung disease group, the ProGRP+ NSE combination was the highest for AUC diagnosis, compared with ProGRP and NSE (P<0.01). In the SCLC ED group serum ProGRP and NSE levels[776.33(3 103.4)ng/L, 52.14(60.59)μg/L]were higher than those in the SCLC LD group[295.59(799.65)ng/L, 23.36(22.97)μg/L], respectively (all P<0.001). The serum ProGRP levels of N0, N1, N2 and N3 in TNM staging were 113.0(343.65), 167.04(724.56), 427.42(1 388.62), 735.99(1 709.95)ng/L respectively (all P<0.001). Serum ProGRP and NSE levels were not statistically different between the sex groups and the age groups (all P>0.05). Conclusion: To establish the cut-off value of serum ProGRP is helpful for the diagnosis and differential diagnosis of SCLC.

Expression of Gab1 lacking the pleckstrin homology domain is associated with neoplastic progression

An in vitro transformation system of carcinogen-treated Syrian hamster embryo (SHE) cell cultures represents multistep genetic and nongenetic changes that develop during the neoplastic progression of normal cells to tumor cells in vivo. During this neoplastic progression, SHE cells demonstrate an altered response to epidermal growth factor (EGF). In the present report, we examined the role of the adapter protein Gab1 (Grb2-associated binder-1) in the neoplastic progression of SHE cells. We used two asbestos-transformed SHE cell clones in different neoplastic stages: a 10W+8 clone, which is immortal and retains the ability to suppress the tumorigenicity of tumor cells in cell-cell hybrid experiments, and a 10W-1 clone, which has lost this tumor suppressor ability. 10W+8 cells expressed full-length 100-kDa Gab1 and associated 5.2-kb mRNA. Upon repeated cell passaging, 10W-1 cells showed increasing expression of a novel 87-kDa form of Gab1 as well as 4.6-kb mRNA with diminishing expression of the original 100-kDa Gab1. cDNA encoding the 87-kDa Gab1 predicts a form of Gab1 lacking the amino-terminal 103 amino acids (Gab1(Delta1-103)), which corresponds to loss of most of the pleckstrin homology (PH) domain. Gab1(Delta1-103) retains the ability to be phosphorylated in an EGF-dependent manner and to associate with the EGF receptor and SHP-2 upon EGF stimulation. The endogenous expression of Gab1(Delta1-103) in 10W-1 cells appeared closely related to EGF-dependent colony formation in soft agar. Moreover, transfection and expression of Gab1(Delta1-103), but not Gab1, in 10W+8 cells enhanced their EGF-dependent colony formation in soft agar. These results demonstrate that Gab1 is a target of carcinogen-induced transformation of SHE cells and that the expression of a Gab1 variant lacking most of the PH domain plays a specific role in the neoplastic progression of SHE cells.

Identification of epidermal growth factor receptor- Grb2-associated binder-1-SHP-2 complex formation and its functional loss during neoplastic cell progression

The adaptor protein Grb2-associated binder-1 (Gab1) is known to bind to the SHP-2 tyrosine phosphatase on epidermal growth factor (EGF) receptor stimulation. To clarify the roles of these two proteins in EGF receptor (EGFR) signaling and determine their possible alteration during neoplastic cell progression, we studied these proteins in a Syrian hamster embryo (SHE) cell line model of neoplastic progression. Specifically, we used asbestos-transformed SHE fibroblasts: the 10W+8 clone, which is immortal but nontumorigenic; and the 10W2T clone, which is tumorigenic. Gab1 was detected, and the EGF-dependent formation of the EGFR-Gab1-SHP-2 complex was observed in 10W+8 cells. After cloning hamster Gab1 cDNA, exogenous expression of Gab1 significantly enhanced EGF-dependent mitogenic activity in 10W+8 cells. On the other hand, Gab1 was not detected in 10W2T cells, and the EGF-dependent association of SHP-2 with EGFR was also absent. Exogenous Gab1 expression in transfected 10W2T cells restored the EGF-dependent association of SHP-2 with EGFR, although it only showed a marginal effect on EGF-dependent mitogenic activity. Thus, Gab1 plays a pivotal role in the EGFR signaling pathway via the formation of the EGFR-Gab1-SHP-2 complex, and alteration in the expression and function of Gab1 is implicated in the neoplastic progression of SHE cells.

The linoleic acid metabolite, (13S)-hydroperoxyoctadecadienoic acid, augments the epidermal growth factor receptor signaling pathway by attenuation of receptor dephosphorylation. Differential response in Syrian hamster embryo tumor suppressor phenotypes

In Syrian hamster embryo (SHE) fibroblasts, epidermal growth factor receptor (EGFR) tyrosine kinase activity regulates the metabolism of endogenous linoleic acid to (13S)-hydroperoxyoctadecadienoic acid (13S)-HPODE). (13S)-HPODE stimulates EGF-dependent mitogenesis in a SHE cell phenotype, which expresses tumor suppressor genes (supB+), but was not effective in a variant that does not express these suppressor genes (supB-). In the present study, we have investigated the potential effects of this lipid metabolite on the EGFR signaling pathways in these two SHE cell lines. Treatment of quiescent SHE cells with EGF produced a rapid, transient increase in the tyrosine phosphorylation of EGFR. Dependence on EGF concentration for EGFR tyrosine phosphorylation was similar in both SHE cell lines, but a more prolonged phosphorylation was detected in the supB- variant. Incubation of supB+ cells with (13S)-HPODE and EGF increased EGFR autophosphorylation and tyrosine phosphorylation on several signaling proteins with Src homology-2 domains including GTPase-activating protein. The lipid metabolite did not significantly alter EGF-dependent tyrosine phosphorylation in the supB- variant. Tyrosine phosphorylation of mitogen-activated protein (MAP) kinase was also measured. The addition of (13S)-HPODE increased the extent and duration of MAP kinase tyrosine phosphorylation in supB+ cells but not in the supB- variant. MAP kinase activity in supB+ cells, as measured in immunoprecipitates from cells after the addition of EGF, was increased by the presence of (13S)-HPODE. The addition of (13S)-HPODE did not directly alter EGFR kinase activity or the internalization of the EGFR. However, the addition of (13S)-HPODE to supB+ cells extended the tyrosine phosphorylation of the EGFR in response to EGF. The dephosphorylation of the EGFR was measured directly, and a slower rate was observed in the supB- compared with the supB+ cells. Incubation of the supB+ cells with (13S)-HPODE attenuated the dephosphorylation of the EGFR. Thus, (13S)-HPODE stimulates EGF-dependent mitogenesis and up-regulation of EGF-dependent tyrosine phosphorylation by inhibiting the dephosphorylation of the EGFR. This study shows that a metabolite of an essential dietary fatty acid, linoleic acid, can modulate tyrosine phosphorylation and activity of key signal transduction proteins in a growth factor mitogenic pathway.