lncRNA‑CASC15 promotes osteosarcoma proliferation and metastasis by regulating epithelial‑mesenchymal transition via the Wnt/β‑catenin signaling pathway

Osteosarcoma (OS) is a rare type of tumor and mostly occurs in children and adolescents. Approximately 10–25% of patients with OS have lung metastases, and lung damage caused by lung metastasis is the main cause of mortality. Therefore, studying the growth and metastasis of OS is key in reducing OS mortality and improving prognosis. The expression of long non-coding RNA (lncRNA) cancer susceptibility 15 (CASC15) in OS patients or OS cell lines were quantified by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The expression of vimentin, E-cadherin, N-cadherin, and cyclin D were detected by RT-qPCR and western blotting. Mice were injected with OS cell lines via the tail vein to observe tumor formation in the lung. CCK-8 and EdU assays were utilized to evaluate cell proliferation. Both Ttranswell assay and cell scratch test detected cell migration. The results revealed that lncRNA-CASC15 was highly expressed in clinical samples and OS cells. In vitro verification experiments revealed that CASC15 promoted the growth of OS cells. Rescue experiments demonstrated that CASC15 affected the cell cycle by activating the Wnt/β-catenin pathway, thereby promoting cell proliferation. Furthermore, the transfection dose test indicated that lentiviruses expressing various doses of CASC15-overexpression (oe-CASC15) altered the proliferation and migration status of OS cells. CASC15 promoted OS cell metastasis both in vivo and in vitro. The overexpression of CASC15 revealed that the occurrence of metastasis was also related to the Wnt/β-catenin pathway. The western blotting results revealed that CASC15 could lead to β-catenin entering the nucleus via the Wnt pathway to promote the epithelial-mesenchymal transition (EMT) of OS cells. To sum up, CASC15 promoted the proliferation of OS cells in vitro and the growth of OS xenograft tumors in vivo. Moreover, CASC15 promoted the entry of β-catenin into the nucleus, thus activating the Wnt pathway and subsequently promoting the EMT of OS cells.

Clinical factors affecting prognosis of limb osteosarcoma in China: a multicenter retrospective analysis

Objective

This study was performed to explore the relationship between various clinical factors and the prognosis of limb osteosarcoma.

Methods

We retrospectively analyzed the clinical data of 336 patients with limb osteosarcoma treated from June 2000 to August 2016 at 7 Chinese cancer centers. Data on the patients’ clinical condition, treatment method, complications, recurrences, metastasis, and prognosis were collected and analyzed. Kaplan–Meier analysis and Cox regression models were used to analyze the data.

Results

The patients comprised 204 males and 132 females ranging in age from 6 to 74 years (average, 21.1 years). The overall 3- and 5-year survival rates were 65.0% and 55.0%, respectively. The 5-year overall survival rate was 64.0% with standard chemotherapy and 45.6% with non-standard chemotherapy. Cox regression analysis demonstrated that standard chemotherapy, surgery, recurrence, and metastasis were independent factors associated with the prognosis of limb osteosarcoma.

Conclusion

The survival of patients with limb osteosarcoma can be significantly improved by combining standard chemotherapy and surgery. The overall survival rate can also be improved by adding methotrexate to doxorubicin–cisplatin–ifosfamide triple chemotherapy.

Clarifying prognostic factors of small cell osteosarcoma: A pooled analysis of 20 cases and the literature

Introduction

Small cell osteosarcoma (SCOS) is a rare subtype of osteosarcoma, with limited studies mainly focusing on histological features. Our study aims to analyze our own patients and those reported in the literature to increase the recognition of this rare disease, to evaluate patient survival and to further determine potential prognostic factors.

Material and methods

Twenty patients with SCOS were treated in our hospital between 2010 and 2019. Their follow-up data were collected retrospectively. A total of 336 literature cases from 58 manuscripts were retrieved by means of a PubMed search with the key word “small cell osteosarcoma”. Data pertaining to treatment and follow-up were extracted. We performed a pooled analysis for the survival of patients and the risk factors for local recurrence (LR), as well as metastatic disease (MD), in a total of 160 patients using the Kaplan-Meier method and Cox regression method.

Results

We reported our experience in diagnosing and treating SCOS. In our cases, elevated alkaline phosphatase (P = 0.013) and lactate dehydrogenase (P = 0.001) significantly impaired overall survival. In the pooled analysis, SCOS was diagnosed at the median age of 17 years and affected both sexes almost equally. The median follow-up duration was 19.5 months. In the pooled analysis cases, the 5-year overall survival rate was 38.6%, and 36.4% of patients survived 10 years. However, an increasing trend was detected, indicating recent improvements in management. The surgical margin status (P = 0.024) and metastases (P = 0.008) significantly impaired overall survival, and the response to chemotherapy was related to disease-free survival (P = 0.012). LR and MD were significantly correlated (P = 0.002) and could be observed after 5 years of follow-up. LR was significantly dependent on response to chemotherapy (P = 0.020). The development of MD seemed to be affected by response to chemotherapy (P = 0.060). Correlations between imaging features and prognosis were not detected.

Conclusions

This study suggested that positive margins, poor response to chemotherapy and MD are negative prognostic factors for SCOS, implied the potential role of laboratory examinations in the survival prediction and supported the need for prolonged or more intensive surveillance in patients with MD or LR. More well-documented literatures are encouraged to allow further confirmations.

Chondromyxoid fibroma-like osteosarcoma: a case series and literature review

BACKGROUND

Chondromyxoid fibroma-like osteosarcoma (CMF-OS) is an exceedingly rare subtype of low-grade central osteosarcoma (LGCO), accounting for up to 10% of cases and making it difficult to diagnose. CMF-OS is frequently misdiagnosed on a radiological examination and biopsy, even after the initial operation. Its treatment is a controversial issue due to its low-grade classification and actual high-grade behavior.

CASE PRESENTATION

We retrospectively reviewed the medical charts of more than 2000 osteosarcoma patients between 2008 and 2019; 11 patients with CMF-OS were identified, of which six patients were treated by our institution with complete clinical characteristics, including treatment and prognosis, radiological and pathological features were reviewed. Three males and three females with a median age of 46 (range 22-56) years were pathologically proven to have CMF-OS. The radiological presentation of CMF-OS is variable, thus radiological misdiagnoses are common. However, one must not ignore a malignant radiologic appearance. The most distinctive pathological feature conferring the diagnosis of CMF-OS is the presence of osteoid production directly by the tumor cells under a chondromyxoid fibroma (CMF)-like background. Differential diagnoses based on comprehensive data from CMF, LGCO, chondrosarcoma (CHS), conventional osteosarcoma (COS), etc., are needed. All patients were treated with an operation and chemotherapy, and one patient received additional radiotherapy. Nevertheless, recurrence and metastasis are common in CMF-OS patients. Relatively invasive biological behavior of CMF-OS is against the low-grade classification of this disease.

CONCLUSIONS

It is important to recognize CMF-OS and distinguish it from CMF, CHS, COS and other LGCOs. CMF-OS has a relatively poor prognosis despite its low-grade classification.

Cytoplasmic APE1 promotes resistance response in osteosarcoma patients with cisplatin treatment

Chemotherapy resistance has become a hold back and major clinical challenge in osteosarcoma cancer. The alteration and subcellular distribution of apurinic/apyrimidinic endonuclease 1 (APE1) has been reported to be involved in chemotherapy resistance in many cancers. Here, we report that the cytoplasmic distribution of APE1 plays a key role in the sensitivity of combination platinum chemotherapy in osteosarcoma. Interestingly, the prevalence of cisplatin-induced DNA damage and apoptosis in low cytoplasmic APE1 osteosarcoma cell lines was higher than in high expression of cytoplasmic APE1 cell lines. Overexpression of cytoplasmic APE1 protected the osteosarcoma cells from CDDP-induced apoptosis. In addition, clinical data also show that the level of cytoplasmic APE1 was negatively associated with sensitivity to combination chemotherapy of cisplatin in osteosarcoma patients. Our findings suggest that cytoplasmic APE1 plays a significant role in chemotherapy resistance. This role is a supplement to the extranuclear function of APE1, and cytoplasmic APE1 expression level could be a promising predictor of platinum treatment prognosis for osteosarcoma patients.

Synergistic inhibitory effects of capsaicin combined with cisplatin on human osteosarcoma in culture and in xenografts

BACKGROUND

The combination of phytochemicals with chemotherapy drugs is an emerging new strategy for cancer therapy to increase antitumor responses.

METHODS

The present study investigates the effect of the combination of capsaicin (CAP) with cisplatin (DDP) and the potential underlying anticancer mechanisms in osteosarcoma (OS) cells in vitro and in vivo.

RESULTS

Cell viability assays and isobolographic analyses demonstrated that the combination of CAP and DDP showed synergistic cytotoxic effects on OS cells. We chose relatively low concentrations of CAP (100 μM) and DDP (16.7 μM) for subsequent experiments. Generally, the combination of CAP and DDP had significant effects on apoptosis induction, cell cycle arrest and cell invasion inhibition in OS cells compared with the individual-treatment groups and the control group. Moreover, cotreatment with CAP and DDP triggered prosurvival autophagy through reactive oxygen species (ROS)/JNK and p-AKT/mTOR signaling in OS cells. The combination regimen of CAP and DDP also inhibited tumor growth in an OS xenograft model.

CONCLUSION

These results suggest that the combination of CAP and DDP has strong inhibitory effects on OS cells and identify CAP as a promising agent for supplementing standard chemotherapy and possible future targeted therapy in OS.

Efficacy and safety of stereotactic radiosurgery for pulmonary metastases from osteosarcoma: Experience in 73 patients

Osteosarcoma pulmonary metastases are typically treated with resection and/or chemotherapy. We hypothesize that stereotactic radiosurgery (SRS) can be an alternative to surgery that can achieve high rates of local control with limited toxicity. From January 2005 to December 2013, 73 patients who developed pulmonary metastasis during period of adjuvant chemotherapy or follow-up were analyzed. 33 patients were treated by stereotactic radiosurgery using the body gamma-knife system. A total dose of 50 Gy was delivered at 5 Gy/fraction to the 50% isodose line covering the planning target volume, whereas a total dose of 70 Gy was delivered at 7 Gy/fraction to the gross target volume. The other 40 patients were treated by surgical resection. Four-year progression-free survival rate, four-year survival rate, median time of PRPFS (post-relapse progress-free survival) and PROS (post-relapse overall survival) in SRS group were parallel to that in surgical group. Patients tolerated gamma knife radiosurgery well. Our study demonstrates that SRS is well-tolerated with excellent local control and less complications. SRS should be considered as a potential option in patients with pulmonary metastases from osteosarcoma, especially in those who are medically inoperable, refuse surgery.

Improvement in High-Grade Osteosarcoma Survival: Results from 202 Patients Treated at a Single Institution in Taiwan

The aim of this study was to compare survival before and after 2004 and define the prognostic factors for high-grade osteosarcomas beyond those of typical young patients with localized extremity disease. Few studies have reported the long-term treatment outcomes of high-grade osteosarcoma in Taiwan. A total of 202 patients with primary high-grade osteosarcoma who received primary chemotherapy at Taipei Veterans General Hospital between January 1995 and December 2011 were retrospectively evaluated and compared by period (1995-2003 vs 2004-2011). Patients of all ages and tumor sites and those following or not following controlled protocols were included in analysis of demographic, tumor-related, and treatment-related variables and survival. Overall survival and progression-free survival at 5 years were, respectively, 67.7% and 48% for all patients (n = 202), 77.3% and 57.1% for patients without metastasis (n = 157), and 33.9% and 14.8% for patients with metastasis (n = 45). The survival rates of patients treated after 2004 were significantly higher (by 13%-16%) compared with those of patients treated before 2004, with an accompanying 30% increase in histological good response rate (P = .002). Factors significantly contributing to inferior survival in univariate and multivariate analyses were diagnosis before 2004, metastasis at diagnosis, and being a noncandidate for a controlled treatment protocol. By comparison with the regimens used at our institution before 2004, the current results support the effectiveness of the post-2004 regimens, which consisted of substantially reduced cycles of high-dose methotrexate and a higher dosage of ifosfamide per cycle, cisplatin, and doxorubicin, for treating high-grade osteosarcoma in Asian patients.

MicroRNA-126 enhances the sensitivity of osteosarcoma cells to cisplatin and methotrexate

The establishment of novel chemotherapy drugs for osteosarcoma is urgently required, and the mechanisms and effects of cisplatin (DDP) and methotrexate (MTX) in the current treatment of osteosarcoma have not been fully elucidated. The present study aimed to observe the effect of DDP, MTX and rapamycin on osteosarcoma cell proliferation and apoptosis, and to investigate the association between miR-126 and the effects of DDP and MTX in osteosarcoma cells. miR-126-overexpressing and -silencing lentiviral vectors were constructed, and MG63 and U-2 OS osteosarcoma cells were infected. An MTT assay was conducted to detect transfected cell proliferation, and the effects of the chemotherapy drugs on transfected cell apoptosis were detected by flow cytometry. The cell cycle of the transfected cells was analyzed via flow cytometry. As the miR-126-overexpressing and -silencing osteosarcoma cell lines were successfully constructed, it was observed that DDP and MTX inhibited osteosarcoma cell proliferation. With the decreased expression of miR-126, the sensitivity of osteosarcoma cells to DDP and MTX was reduced at the same concentration. The flow cytometry suggested that DDP and MTX could promote the apoptosis of osteosarcoma cells with overexpressed miR-126, whereas they could not significantly impact the apoptosis of the miR-126-silenced osteosarcoma cells. Meanwhile, DDP inhibited the cell cycle of the miR-126-overexpressing osteosarcoma cells. In conclusion, DDP and MTX inhibited the proliferation and promoted the apoptosis of the osteosarcoma cells, and these processes were dependent upon the expression of miR-126.

Gemcitabine for the treatment of patients with osteosarcoma

BACKGROUND

Patients with recurrent or refractory osteosarcoma are considered to have a very poor prognosis, and new regimens are needed to improve the prognosis in this setting. Gemcitabine, a nucleoside antimetabolite, is an analog of deoxycytidine which mainly inhibits DNA synthesis through interfering with DNA chain elongation and depleting deoxynucleotide stores, resulting in gemcitabine-induced cell death. Here we performed a systemic analysis to evaluate gemcitabine based chemotherapy as salvage treatment for patients with recurrent or refractory osteosarcoma.

METHODS

Clinical studies evaluating the impact of gemcitabine based regimens on response and safety for patients with osteosarcoma were identified by using a predefined search strategy. Pooled response rates (RRs) of treatment were calculated.

RESULTS

In gemcitabine based regimens, 4 clinical studies which included 66 patients with recurrent or refractory osteosarcoma were considered eligible for inclusion. Systemic analysis suggested that, in all patients, pooled RR was 12.1% (8/66) in gemcitabine based regimens. Major adverse effects were hematologic toxicity, including grade 3 or 4 anemia, leucopenia and thrombocytopenia in gemcitabine based treatment. No treatment related death occurred in gemcitabine based treatment.

CONCLUSION

This systemic analysis suggests that gemcitabine based regimens are associated with mild activity with good tolerability in treating patients with recurrent or refractory osteosarcoma.

Synergistic growth inhibition by sorafenib and cisplatin in human osteosarcoma cells

Molecular-targeted therapy has shown promise as a treatment for advanced osteosarcoma (OS). Sorafenib (SOR), a multikinase inhibitor, is the approved systemic drug of choice for OS, but has demonstrated limited benefits due to its toxicity and other adverse effects. Therapy strategies for reducing toxicity include using lower doses of SOR in combination with other complementary agents. Cisplatin (CDDP) has been shown to be a promising anticancer drug against various types of cancer including OS. In the present study, SOR was combined with CDDP to determine whether this combinatorial treatment suppressed tumor growth thereby simultaneously reducing doses of the two drugs for the treatment of OS. Human Saos-2 OS cells were treated with SOR and CDDP, alone and in combination, and the effect of these treatments on cell proliferation, colony formation, cell cycle, apoptosis, migration, and invasion, and involvement in receptor signaling, as well as tumor growth ability in nude mice was determined. It was found that the combination of low concentrations of SOR and CDDP significantly suppressed the cell proliferation, colony formation, migration and invasion, and induced cell apoptosis and cell cycle arrest in the G0/G1 stage, and suppressed tumor growth in a nude mouse model compared to the actions of either agent alone. The results also showed that SOR in combination with CDDP significantly suppressed the phosphorylation of extracellular signal-regulated kinase (ERK), which may contribute to the inhibition of tumor growth. These results suggested that SOR in combination with CDDP acts synergistically in the treatment of OS.

Ifosfamide-containing regimens for treating patients with osteosarcomas

BACKGROUND

This systemic analysis was conducted to evaluate the efficacy and safety of an ifosfamide- containing regimen in treating patients with osteosarcoma.

METHODS

Clinical studies evaluating the efficacy and safety of Ifosfamide-containing regimen on response and safety for patients with osteosarcoma were identified by using a predefined search strategy. Pooled response rate (RR) of treatment were calculated.

RESULTS

When ifosfamide-containing regimens were evaluated, 4 clinical studies which including 134 patients with osteosarcoma were considered eligible for inclusion. Systemic analysis suggested that, in all patients, pooled RR was 44.8% (60/134) in ifosfamide-containing regimens. Major adverse effects were neutropenia, leukopenia, and fatigue inIfosfamide-containing regimens; No treatment related death occurred in cantharidin combined regimens.

CONCLUSION

This systemic analysis suggests that ifosfamide-containing regimens are associated with good response rate and acceptable toxicity in treating patients with osteosarcoma, but this result should be confirmed by randomized clinical trials.

Pirarubicin versus doxorubicin in neoadjuvant/adjuvant chemotherapy for stage IIB limb high-grade osteosarcoma: does the analog matter?

Pirarubicin (THP), a novel anthracycline derivative of doxorubicin (ADM), is effective in treating patients with advanced, relapsed or recurrent high-grade osteosarcoma. But its role in neoadjuvant/adjuvant chemotherapy of osteosarcoma is still not defined. We conducted a retrospective evaluation of THP-containing chemotherapy for osteosarcoma in comparison with ADM-containing chemotherapy to determine differences in efficacy and toxicities between THP- and ADM-containing regimens. From January 2008 to May 2011, 112 stage IIB limb high-grade osteosarcoma patients were treated in our institute. Fifty-four patients received a median 6 cycles of neoadjuvant/adjuvant chemotherapy consisted of THP (pirarubicin), DDP (cisplatin), IFO (ifosfamide) and MTX (methotrexate), while 58 patients received a median 6 cycles of neoadjuvant/adjuvant chemotherapy consisted of ADM (doxorubicin), DDP (cisplatin), IFO (ifosfamide) and MTX (methotrexate). Efficacy and toxicity of the 2 anthracyclines given as combination chemotherapy were assessed in these patients. The limb salvage rate, histologic response rate, 2-year recurrence rate, 2-year metastasis rate, 2-year disease-free survival rate, 2-year overall survival rate, median disease-free survival time (DFS) and median overall survival time (OS) in THP-containing group were similar to that in ADM-containing group. Toxicities were well balanced in two groups. No death related to chemotherapy was observed. Left ventricular ejection fraction was unchanged 1 and 2 years after chemotherapy in two groups. Efficacy and toxicity of THP-containing combination are similar to those of ADM-containing combination in neoadjuvant/adjuvant chemotherapy for stage IIB limb high-grade osteosarcoma.

Experience of pediatric osteosarcoma of the extremity at a single institution in Taiwan: prognostic factors and impact on survival

PURPOSE

To identify the prognostic factors and evaluate the impact of chemotherapy regimens on the outcomes of pediatric osteosarcoma of the extremities.

METHODS

Patients younger than 18 years and diagnosed with high-grade osteosarcoma of the extremities during the period between January 2004 and December 2011 were included for retrospective analysis. Demographic characteristics and tumor features were compared between nonmetastatic and metastatic patients. Univariate analyses of overall survival (OS) and progression-free survival (PFS) were performed to evaluate the efficacy of various chemotherapy regimens.

RESULTS

A total of 74 patients (58 with nonmetastatic and 16 with metastatic disease) were enrolled and treated with three protocols consisting of various cycles of high-dose methotrexate, adriamycin (doxorubicin), cisplatin, and high-dose ifosfamide (MACI regimens) during the 8-year study period. Presence of metastasis was inversely correlated with OS and PFS. Alkaline phosphatase levels at diagnosis and histologic response to preoperative chemotherapy were correlated with OS. Tumor size was correlated with PFS. The 5-year OS and PFS were 77 and 70 % for all patients, and 90.4 and 83.3 % for those with nonmetastatic osteosarcoma; and the rates were both 25 % in those with metastatic osteosarcoma. The chemotherapy regimens increased good response rates by 30 % and survival rates by 20 % compared to the outcomes in patients treated before 2004.

CONCLUSIONS

Poor prognostic factors for osteosarcoma in pediatric patients were identified under homogeneous surgical and chemotherapy schemes. The four-drug regimens consisting of MACI contributed to the remarkably increased good response rates and consequent improvement in the survival rates.

Synergistic apoptotic effect of crocin and cisplatin on osteosarcoma cells via caspase induced apoptosis

Crocin is well-known traditional Chinese medicine which is extracted from saffron. However, its role in osteosarcoma has not been well understood. Therefore, we used crocin and cisplatin individually or jointly on MG63 and OS732 cells so as to explore whether crocin could induce cellular apoptosis and suppress the ability of invasion of osteosarcoma cells. Cell survival rates, changes of cellular shape, cell apoptosis and cell invasion were analyzed, respectively, by 3-(4,5)-dimethylthiahiazo (-z-y1)-2,5-di- phenytetrazoliumromide (MTT) assay, inverted phase contrast microscope and fluorescence microscope, flow cytometry, and Transwell invasion chamber methods. The expressions of caspase-3 and caspase-8 were detected by Western blot. The survival rate of combined application was significantly lower than that of the individual application. Apoptosis-inducing effect of combined application was much stronger than that of individual application. The invasion ability of MG63 and OS732 cells was restrained significantly in the combined group compared with the individual group and control group. Combined group has the effect of up-regulating the expressions of cleaved-caspase-3 and caspase-8. The results suggested that combination of crocin and cisplatin has a strong killing effect on osteosarcoma cells and suppresses the ability of invasion of MG63 and OS732 cells which might be related to up-regulate the expression of caspase-3 and caspase-8.

Oxaliplatin sensitizes OS cells to TRAIL-induced apoptosis via down-regulation of Mcl1

PURPOSE

To investigate the killing effect on OS cells of a combination of oxaliplatin and TRAIL and related molecular mechanisms.

METHODS

TRAIL and oxaliplatin were applied to OS732 cells singly or jointly and survival inhibition rates were measured by MTT assay, changes of cellular shape being assessed with inverted phase contrast and fluorescence microscopy. Apoptotic rates were analyzed by flow cytometry (FCM) and immunocytochemistry was used to examine Mcl1 expression of OS732 cells.

RESULTS

The survival inhibition rate of combined application of 100 μg/ml TRAIL and 1 μg/ml oxaliplatin on OS-732 cells was significantly higher than that of either agent singly (p<0.01). Changes of cellular shape and apoptotic rates also indicated apoptosis-inducing effects of combined application to be much stronger than those of individual application. Oxaliplatin had the effect of down-regulating Mcl1 expression and sensitizing OS cells to TRAIL-induced apoptosis.

CONCLUSION

A combination of TRAIL and oxaliplatin exerts strong killing effects on OS-732 cells which might be related to down-regulation of Mcl1 expression.

Suboptimal chemotherapy is an adverse prognostic factor in osteosarcoma

BACKGROUND

We sought to determine whether suboptimal chemotherapy compromised the prognosis of osteosarcoma patients.

METHODS

A total of 132 eligible patients who underwent chemotherapy between 1998 and 2008 were identified in our database. Information regarding patient demographics, clinical characteristics, and survival status were extracted for analysis. Optimal chemotherapy was defined as receipt of ≥80% of the planned dose intensity of prescribed agents within the planned durations.

RESULTS

The use of optimal chemotherapy resulted in an overall survival benefit with P = 0.006. Patients who failed to complete the optimal chemotherapy protocol had a dismal prognosis of 30.8% overall survival over five years, whereas those who completed the optimal chemotherapy had an overall survival rate over five years of 65.3%. Based on multivariate analysis, patients who were treated with a suboptimal protocol had a higher risk of relapse, metastasis and mortality. The hazard ratio (HR) of recurrence or death for the suboptimal chemotherapy group was as high as 2.512 over that of the optimal chemotherapy group (HR = 2.512, 95% confidence interval = 1.242 to 3.729).

CONCLUSIONS

Chemotherapy is a significant independent prognostic variable, and suboptimal chemotherapy was found to have a detrimental effect on the outcome of patients with osteosarcoma.