[Molecular genetic abnormalities of N-myc and C-myc in pediatric neuroblastic tumors and clinical pathologic significance].

OBJECTIVE: To investigate the molecular genetic abnormalities of N-myc and C-myc, and their clinical pathological implications in pediatric neuroblastic tumors (NTs). METHODS: Abnormalities of N-myc were detected by interphase fluorescence in situ hybridization (FISH) technique in 246 cases of NTs, including neuroblastoma (NB,188 cases), ganglioneuroblastoma (GNB, 52 cases), ganglioneuroma (GN, 6 cases), and their association with the histological typing of the tumors and prognosis was analyzed. Abnormalities of C-myc were detected by FISH in 133 cases of NTs. RESULTS: Of the 246 cases of NTs, N-myc amplification was only found in 27 cases (11.0%, 27/246) of NB, but not in any cases of GNB or GN (P < 0.05). 89.0% (219/246) N-myc non-amplification were found in NTs, and it included N-myc gain in 175 cases (71.1%, 175/246) and normal N-myc in 44 cases (17.9%, 44/246). Univariate analysis indicated significantly (P = 0.012) poorer outcome in patients with N-myc amplification than N-myc non-amplification. However no significant difference was observed between N-myc gain cases and normal N-myc cases (P = 0.057). C-myc gain was found in 74 of 133 cases (55.6%) of NTs; no C-myc amplification or translocation was detected. Forty percent (6/15) of cases with N-myc amplification and 57.6% (68/118) of cases with N-myc non-amplification were accompanied by C-myc gain. The difference between N-myc amplification and non-amplification with C-myc gain was not significant (P > 0.05). Univariate analysis indicated that the outcome difference was not statistically significant between C-myc gain cases and normal C-myc cases (P = 0.357). CONCLUSIONS: The incidence of N-myc amplification only found in NB is low in pediatric NTs in China. Patients with N-myc amplification predict poorer outcome. No amplification or translocation of C-myc is detected in NTs, whereas C-myc gain is relatively common in NTs. There is no obvious association between N-myc amplification and C-myc gain.

[Vascular cell adhesion molecule-1, eotaxin and vascular endothelial growth factor in nasal polyps after endoscopic surgery].

OBJECTIVE: To study the different expression of VCAM-1, eotaxin and VEGF in nasal polyp tissues and in the nasal mucosa of the operative cavity after endoscopic surgery and its significance. METHODS: Paraffin sections of nasal polyps and the nasal mucosa of the operative cavity were studied with immunohistochemical technique and HE staining. RESULTS: (1) Abundant eosinophils were observed in the nasal polyps, however, it was rarely seen in the nasal mucosa of the operative cavity (t = 2.891, P <0.05). (2) The positive expression of VCAM-1 and eotaxin was in nasal polyps and nasal mucosa of operative cavity, and both of the positive area were not statistically significant (t = - 2.051, P > 0.05), but their average density of light was decreased in the nasal mucosa of the operative cavity (t = 3.670, P = 0.05). The positive glandular of eotaxin were increased after endoscopic surgery (t = -2.899, P < 0.05). (3) Expression of VEGF was similar in both groups (t = - 0.037, 0.825, P > 0.05, respectively). CONCLUSIONS: (1) It is suggested that the nasal mucosa of the operative cavity was different from the nasal polyps. (2) The positive expression of VCAM-1 and eotaxin in the nasal mucosa of the operative cavity after endoscopic surgery indicates that eotaxin may up-regulate the expression of VCAM-1 in vessel endothelium and promote adhesion and migration of eosinophils, as a result, to lead to the recurrence of nasal polyps. The glandulous expression of eotaxin may play a key role in the early stage. (3) The expression of VEGF in nasal mucosa after surgery may contribute to the growth of blood vessel and induce increasing of vascular permeability and tissue edema. This may be an important factor in the process of nasal polyp recurrence.