Materials and Methods: This work was focused on diagnosing osteosarcoma (OS), a common bone cancer, on MXene-modified multiple junction triangles by dielectrode sensing. Survivin protein gene is highly correlated with OS, identified on this sensing surface. Capture DNA was immobilized on MXene by using 3-glycidoxypropyltrimethoxysilane as an amine linker and duplexed by the target DNA sequence.
Results: The limitation and sensitivity of detection were found as 1 fM with the acceptable regression co-efficient value (y=1.0037⨰ + 0.525; R2=0.978) and the current enhancement was noted when increasing the target DNA concentrations. Moreover, the control sequences of single- and triple-mismatched and noncomplementary to the target DNA sequences failed to hybridize on the capture DNA, confirming the specificity. In addition, different batches were prepared with capture probe immobilized sensing surfaces and proved the efficient reproducibility.
Conclusion: This microgap device with Mxene-modified multiple junction triangles dielectrode surface is beneficial to quantify the survivin gene at its lower level and diagnosing OS complication levels.
METHOD: This is a retrospective survival analysis study of 128 patients treated at University Malaya Medical Centre (UMMC) from 1997 to 2011.
RESULTS: There were 80 (62.5%) male and 48 (37.5%) female patients with the median age being 15 (5-59). Majority had osteosarcoma of extremities (94.5%). More than 60% patients developed metastasis throughout the course of treatment with 39% presenting with lung metastasis. Osteoblastic osteosarcoma was the commonest subtype (65.6%). Of the 109 patients treated surgically, 84 patients (65.6%) underwent limb salvage surgery while the rest underwent amputation. Seventy-one per cent of patients completed treatment with local recurrence rate of 22.7%. The 5-year and 10-year survival rates were 56.31% (95% CI: 46.20, 65.24) and 22.33% (95% CI: 14.86, 30.76), respectively. The 5-year event-free survival was 52.94% (95% CI: 41.83, 62.87). In multivariate analysis, the independent prognostic factors were presence of metastasis and completion of treatment for both 5-year and 10-year overall survival. Good histological response was only significant for multivariate analysis at 5 years. Patients with metastasis had a hazard ratio of 20.4 at 5 years and 3.26 at 10 years.
CONCLUSION: Overall survival rate for osteosarcoma patients at our centre was comparably higher than other centres in the region. Two independent risk factors for survival are metastatic status and completion of treatment. A standardized chemotherapy regime is essential for long-term survival.
METHODS: One hundred osteosarcoma cases from 2003 to 2018 in Hospital Universiti Sains Malaysia were retrieved. The tissue samples were stained for RANKL, and the association with the clinicopathological characteristics was evaluated. Staining was interpreted in a semiquantitative scoring system and classified into negative and positive expressions. Results: Eighty-two cases had a positive expression of RANKL in which 56 and 26 patients were classified as low expression and high expression, respectively. The positive expression of RANKL did not show a significant association with clinicopathological characteristics. However, Kaplan Meier survival analysis showed a significant improvement in the disease-free survival patients who underwent limb salvage surgery (LSS) than amputated patients (p-value 0.002), whereas poorer survival was observed among conventional osteosarcomas compared to non-conventional osteosarcoma (p-value 0.01).
CONCLUSION: Limb salvage surgery had proven to improve osteosarcoma patients' survival compared to amputation, which could improve overall quality of life in osteosarcoma patients. However, our data did not show a significant association between positive RANKL immunohistochemistry with any of the clinicopathological characteristics and patients' final survival. Further studies may be acquired to understand the suitability of using RANKL immunohistochemistry as prognostication in the management of osteosarcoma patients.
RESULTS: Tumors with a variety of clinical and pathological characteristics were selected. Gene expression stability and the optimal number of reference genes for gene expression normalization were calculated. RPS5 and HNRNPH were highly stable among OS cell lines, while RPS5 and RPS19 were the best combination for primary tumors. Pairwise variation analysis recommended four and two reference genes for optimal normalization of the expression data of canine OS tumors and cell lines, respectively.
CONCLUSIONS: Appropriate combinations of reference genes are recommended to normalize mRNA levels in canine OS tumors and cell lines to facilitate standardized and reliable quantification of target gene expression, which is essential for investigating key genes involved in canine OS metastasis and for comparative biomarker discovery.