[Parameningeal or non-parameningeal head and neck rhabdomyosarcoma: a study based on propensity score matching and survival analysis]

Objective: To compare the prognoses between parameningeal and non-parameningeal head and neck rhabdomyosarcoma based on propensity score matching and to explore the prognostic factors of overall survival in patients with head and neck rhabdomyosarcoma. Methods: The medical records of 64 patients with pathologically diagnosed as head and neck rhabdomyosarcoma from January 2016 to May 2020 in Peking Union Medical College Hospital were retrospectively retrieved, including 31 males and 33 females, with an average age of (8.0±8.9) years. Kaplan-Meier method was used to draw and compare survival curves in subgroup analysis according to different histopathological characteristics. Patients were divided into non-parameningeal (27 cases) and parameningeal (37 cases) group based on the location of primary lesion. Patients were further selected using 1∶1 propensity score matching method. The basic clinical data and overall survival were compared before and after matching. Prognostic factors were anlysed using Cox's proportional hazards regression model. Results: In 64 patients with head and neck rhabdomyosarcoma, lower risk stratification, and lower TNM stage indicated higher overall survival (all P<0.05). Before matching, patients in parameningeal group presented with higher T stage and IRS (Intergroup Rhabdomyosarcoma Study) staging (all P<0.05). There were no significant differences in basic clinical data and 1-, 2-, and 3-year overall survival rates between two groups after matching(P>0.05). Tumor size smaller than 5 cm, embryonal histology, negative FOXO1 fusion gene, lower risk stratification, and lower TNM stage were associated with higher overall survival (all P<0.05). Among these, tumor size and histology were independent prognostic factors (HR=2.36, 95%CI:1.07-5.20, P=0.033; HR=5.54, 95%CI: 1.18-25.95, P=0.030). Conclusions: There is no significant difference in overall survival between patients with parameningeal and non-parameningeal rhabdomyosarcomas. Tumor size smaller than 5 cm and embryonal histology are two independent prognostic factors.

Targeting role of glioma stem cells for glioblastoma multiforme

Glioblastoma multiforme (GBM) is known to be the most common and lethal malignant primary brain tumor. Despite vigorous basic and clinical studies over the past decades, the prognosis of patients with GBM has remained dismal. The fundamental problem with these malignancies occurs due to tumor cells' highly infiltrative nature, precluding a complete surgical resection, and a productive or acquired resistance to cytotoxic therapy. Recent studies demonstrated that GBMs exhibited remarkable cellular heterogeneity and hierarchy containing self-renewing glioma stem cells (GSCs). The malignant growth of GBM can be propagated and sustained by GSCs that are endowed with highly efficient clonogenic and tumor initiation capacities. GSCs can be identified with technical support and are responsible for the invasive potential and recurrence of GBMs. They share core signaling pathways with normal neural stem cells, but also display critical distinctions that provide important clues for useful therapeutic targets. Therefore, targeting GSCs becomes priorities for the development of novel therapeutic paradigms. Herein, we reviewed the existing and promising targeting therapies for GSCs which could effectively inhibit the tumor invasion, proliferation and recurrence of GBMs. Significant features of GSCs, such as invasive growth pattern, angiogenic potential, resistance to traditional therapy and differentiation, are important therapeutic targets. More promising strategies should target GSCs themselves by taking advantages of highthroughput technologies and dissecting the intrinsic molecular nature of GSCs. Novel chemical medicines targeting these GSCs may represent one of the most important directions. Hopefully, this could shed a light on the path we are going to.

The brain-derived neurotrophic factor is associated with alcohol dependence-related depression and antidepressant response

Brain-derived neurotrophic factor (BDNF) plays an essential role in neuronal survival, proliferation, and synaptic remodeling and modulates the function of many other neurotransmitters. Additionally, it likely underlies neurodegenerative and psychiatric disorders, including alcohol dependence-related depression (AD-D). Here, we investigated the possible association between three single nucleotide polymorphisms (SNPs) of the BDNF gene (rs13306221, rs6265, rs16917204) and AD-D. Of 548 patients with alcohol dependence (AD), 166 had AD-D and 312 healthy controls. Response to 8-week sertraline treatment was also assessed. The frequency of the A allele of rs6265 (Val66Met) was significantly higher in AD-D patients than in the healthy controls (p=0.009 after Bonferroni correction). The analysis revealed a strong association between the rs6265 genotype distribution and AD-D (p=0.005 after Bonferroni correction), and the A allele of rs6265 was significantly overrepresented in AD-D patients compared to AD without depression (AD-nD) patients (p=0.001 after Bonferroni correction). Additionally, carriers of the A allele of rs6265 responded better to sertraline treatment (p=0.001). Our results suggested a novel association between BDNF rs6265 and AD-D. These findings might lead to earlier detection of AD-D, perhaps providing better tools for clinical care of these patients in the future.

Expression and localisation of urokinase-type plasminogen activator gene in gliomas

Urokinase-type plasminogen activator (uPA) activity is related to the malignant biological behaviour of tumours. In the present study, we examined the presence and distribution of uPA in human gliomas. The amounts of uPA were measured by Northern blotting hybridisation and immunohistochemistry in 43 gliomas and five normal brain specimens. Their relation to the clinical history was comprehensively analysed. All tissues expressed 2.5 kb transcripts of uPA mRNA. The uPA mRNA levels were significantly higher in high grade gliomas than they were in low grade gliomas and normal brain tissue (P < 0.01). Levels of uPA mRNA expression in tumour tissues with recurrence within 18 months postoperatively and survival less than 3 years were significantly higher than counterparts (P < 0.01). The uPA mRNA was also expressed in tumour cells near necrotic areas. The uPA protein expression was consistent with the uPA mRNA expression. The distribution of uPA protein immunoreactivity was mainly in tumour cells and microvascular endothelial cells of glioblastomas and anaplastic astrocytomas, localising in the cytoplasm, especially at sites of vascular proliferation and at the leading edges of tumours. These results suggest that expression of the uPA gene is associated with the malignant progression of gliomas and may play an important role in the recurrence and invasive behaviors of higher grade gliomas.

Expression of the simian virus 40 large tumor antigen (Tag) and formation of Tag-p53 and Tag-pRb complexes in human brain tumors

BACKGROUND

The presence of simian virus 40 (SV40) in human brain tumors remains a controversial issue. Even if SV40 does exist in brain tumors, the questions of whether it is associated with brain tumorigenesis and by what mechanisms are unknown.

METHODS

SV40 large tumor antigen (Tag) was investigated by immunoprecipitation, silver staining, and Western blot analysis in 65 brain tumor cases and 8 cases of normal brain tissue. Tag-p53 and Tag-pRb complexes were screened by immunoprecipitation and Western blot analysis in 18 and 15 Tag positive tumor tissues, respectively.

RESULTS

Tag was found in all 8 cases of ependymoma and 2 cases of choroid plexus papilloma, 90% of pituitary adenoma cases (9 of 10), 73% of astrocytoma cases (11 of 15), 70% of meningioma cases (7 of 10), 50% of glioblastoma multiforme cases (4 of 8), and 33% of medulloblastoma cases (2 of 6). Five oligodendroglioma cases, 1 pineocytoma case, and 8 cases of normal brain tissue were negative for Tag. The Tag-p53 complex was detected in all 18 Tag positive tumors tested and the Tag-pRb complex was detected in all 15 Tag positive tumors tested.

CONCLUSIONS

SV40 Tag not only is expressed in brain tumors; it also can form specific complexes with tumor suppressors p53 and pRb. SV40 is correlated with brain tumorigenesis. The inactivation of p53 and pRb due to the formation of Tag-p53 and Tag-pRb complexes possibly is a significant mechanism in the etiopathogenesis of brain tumors.