p16 expression predicts neoadjuvant tumor necrosis in osteosarcomas: reappraisal with a larger series using whole sections

A murine mesenchymal stem cell model for initiating events in osteosarcomagenesis points to CDK4/CDK6 inhibition as a therapeutic target

Osteosarcoma is a high-grade bone-forming neoplasm, with a complex genome. Tumours frequently show chromothripsis, many deletions, translocations and copy number alterations. Alterations in the p53 or Rb pathway are the most common genetic alterations identified in osteosarcoma. Using spontaneously transformed murine mesenchymal stem cells (MSCs) which formed sarcoma after subcutaneous injection into mice, it was previously demonstrated that p53 is most often involved in the transformation towards sarcomas with complex genomics, including osteosarcoma. In the current study, not only loss of p53 but also loss of p16^Ink4a is shown to be a driver of osteosarcomagenesis: murine MSCs with deficient p15^Ink4b, p16^Ink4a, or p19^Arf transform earlier compared to wild-type murine MSCs. Furthermore, in a panel of nine spontaneously transformed murine MSCs, alterations in p15^Ink4b, p16^Ink4a, or p19^Arf were observed in eight out of nine cases. Alterations in the Rb/p16 pathway could indicate that osteosarcoma cells are vulnerable to CDK4/CDK6 inhibitor treatment. Indeed, using two-dimensional (n = 7) and three-dimensional (n = 3) cultures of human osteosarcoma cell lines, it was shown that osteosarcoma cells with defective p16^INK4A are sensitive to the CDK4/CDK6 inhibitor palbociclib after 72-hour treatment. A tissue microarray analysis of 109 primary tumour biopsies revealed a subset of patients (20-23%) with intact Rb, but defective p16 or overexpression of CDK4 and/or CDK6. These patients might benefit from CDK4/CDK6 inhibition, therefore our results are promising and might be translated to the clinic.

The Plasma Concentration of D-Dimer is Associated with Neoadjuvant-Chemotherapy Efficacy and the Prognosis in Osteosarcoma

PURPOSE

This retrospective study explored the clinical value of the plasma D-dimer level in osteosarcoma.

MATERIALS AND METHODS

We measured the plasma D-dimer level before neoadjuvant chemotherapy (D0) and the plasma D-dimer level after four courses of neoadjuvant chemotherapy (D1) in 103 patients with stage-IIB high-grade osteosarcoma of the limb. The change in the D-dimer level (ΔD) was defined as D1 minus D0. The chi-square test was used to compare categorical variables. Analyses of receiver operating characteristic (ROC) curves were undertaken to determine the optimal cutoff points for D0, D1, and ΔD. The area under the ROC (AUC) of D0, D1, and ΔD was calculated to evaluate their discriminatory abilities in monitoring the response to neoadjuvant chemotherapy (tumor necrosis). Survival curves were generated according to Kaplan-Meier analyses and compared using the Log rank test. Univariate analyses and multivariate analyses were carried out to determine independent prognostic factors.

RESULTS

Kaplan-Meier curves showed that a high D-dimer level at D0 and tumor diameter ≥8 cm were associated significantly with worse overall survival (OS) (P<0.05). Multivariate Cox regression analyses revealed a high D-dimer level at D0 (hazard ratio, 3.92; 95% confidence interval, 1.756-5.804; P=0.000) was an independent unfavorable prognostic factor. The chi-square test showed ΔD to be associated significantly with tumor necrosis. Analyses of ROC curves showed the D-dimer level at D0 and ΔD had better ability compared to that at D1 to discriminate the response to neoadjuvant chemotherapy.

CONCLUSION

The D-dimer level was correlated with the prognosis and response to chemotherapy in patients with stage-IIB high-grade osteosarcoma of the limb. The D-dimer level may serve as a risk factor of the response to chemotherapy and prognosis of localized osteosarcoma.

Effects of glabridin combined with 5-fluorouracil on the proliferation and apoptosis of gastric cancer cells

Gastric cancer most commonly occurs in East Asia, and China accounts for more than half the of world's gastric cancer burden. Despite the efficacy of chemotherapy for patients, this treatment leads to significant patient inconvenience, toxicity and cost. The present study aimed to assess a non-toxic agent, glabridin, as a future chemotherapeutic approach for treating gastric cancer. Using cell proliferation, apoptosis, invasion, and colony formation assays, it was determined that glabridin alone, or in combination with 5-fluorouracil (5-FU), inhibited MKN-45 cell proliferation and invasion, and increased apoptosis. These effects were accompanied by downregulation of p16, E-cadherin and apoptosis regulator Bcl-2 protein, and upregulation of N-cadherin, apoptosis regulator BAX and caspases 3, 8 and 9. The results demonstrated that glabridin may inhibit the malignant proliferation of the human gastric cancer MKN-45 cell line and enhance the efficiency of 5-FU. The data indicate that the p16, and potentially the p16/cyclin-dependent kinase 4/cyclin D1 pathway, may be a novel target for gastric cancer therapy.

Meta-analysis of clinical significance of p53 protein expression in patients with osteosarcoma

AIM

The prognostic role of p53 protein expression in osteosarcoma has been reported, but the results remain conflicting.

MATERIALS & METHODS

The relevant literature databases were searched to get eligible articles published in English. The overall ORs or HRs and their corresponding 95% CIs were calculated.

RESULTS

The results indicated that p53 protein expression was not linked to age factor, gender, tumor grade, cancer metastasis and response to chemotherapy. p53 expression was significantly lower in osteogenic osteosarcoma than in nonosteogenic osteosarcoma (OR = 0.40; p = 0.006). p53 expression was associated with a poor prognosis of patients in overall survival (univariate analysis: HR: 2.49; p < 0.001 and multivariate analysis: HR: 2.92; p < 0.001).

CONCLUSION

p53 expression was correlated with pathological type and may become a useful prognostic biomarker in overall survival in osteosarcoma.

P16 protein expression as a useful predictive biomarker for neoadjuvant chemotherapy response in patients with high-grade osteosarcoma: A systematic meta-analysis under guideline of PRISMA

BACKGROUND

Neoadjuvant chemotherapy for patients with high-grade osteosarcoma has highly improved the clinical survival. However, the prognostic and predictive role of P16 expression after neoadjuvant chemotherapy remains unclear. We first determined whether P16 expression can become a potential prognostic and predictive biomarker in high-grade osteosarcoma.

METHODS

This meta-analysis was conducted based on the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guideline. Eligible studies were pooled and the overall odds ratios (ORs) and hazard ratios (HRs) with the corresponding 95% confidence intervals (95% CIs) were calculated in this analysis.

RESULTS

Four studies involving a total of 527 patients with high-grade osteosarcoma receiving neoadjuvant chemotherapy were identified. We did not find that P16 expression was correlated with sex status, histologic subtype, and tumor site (P > .1). P16 expression was found to be significantly associated with a "good" response to neoadjuvant chemotherapy (OR = 4.69, P < .001). A significant relationship was observed between p16 expression and pathologic complete response after neoadjuvant chemotherapy using multivariate analysis (OR = 9.63, P = .001). The expression of the P16 was not associated with clinical outcomes in overall survival (OS) and disease-free survival (DFS) by multivariate analysis (OS: P = .448; DFS: P = .263).

CONCLUSIONS

The use of P16 expression could become a promising predictive biomarker of the response to neoadjuvant chemotherapy in the white population with high-grade osteosarcoma. However, it was not correlated with the prognosis of patients in OS and DFS. More clinical researches are very essential in Asians in the future.