Multiple primary malignancies in osteosarcoma patients. Incidence and predictive value of osteosarcoma subtype for cancer syndromes related with osteosarcoma

Quercetin and Methotrexate in Combination have Anticancer Activity in Osteosarcoma Cells and Repress Oncogenic MicroRNA-223

INTRODUCTION

Osteosarcoma (OS) is one of the most common bone neoplasms in adolescents. Notable short- and long-term toxic effects of OS chemotherapy regimens have been reported. Hence, new chemotherapeutic agents with the ability to potentiate OS chemotherapy drugs and protect non-tumorous tissues are required.

METHODS

Saos-2 cells were treated with Methotrexate (MTX) and Quercetin (Que) (a polyphenolic flavonoid with anti-tumor effects) alone and in combination. MTT assay was performed to investigate the cytotoxicity of the drugs. Moreover, apoptosis-involved genes, including miR-223, p53, BCL-2, CBX7, and CYLD expression were analyzed via qRT-PCR. Annexin V-FITC/PI kit was employed to assess the apoptosis rate.

RESULTS

The MTT results showed that Que increases MTX cytotoxicity on OS cells. The measured IC50s are 142.3 µM for QUE and 13.7 ng/ml for MTX. A decline in MTX IC50 value was observed from 13.7 ng/ml to 8.45 ng/ml in the presence of Que. Moreover, the mRNA expression outcomes indicated that the combination therapy significantly up-regulates the tumor suppressor genes, such as p53, CBX7, and CYLD, and declines anti-apoptotic genes BCL-2 and miR-223, which can lead to proliferation inhibition and apoptosis inducement. Furthermore, the apoptosis rate increased significantly from 6.03% in the control group to 38.35% in Saos-2 cells that were treated with the combination of MTX and Que.

CONCLUSION

Que, with the potential to boost the anticancer activity of MTX on Saos-2 cancer cells through proliferation inhibition and apoptosis induction, is a good candidate for combination therapy.

Metachronous breast cancer in a male with previous history of liposarcoma: A case report from Syria

Introduction

Multiple primary cancers (MPC) are defined as the occurrence of two or more non-related cancers. The acquiring of male breast cancer (MBC) as secondary cancer in a sequence of MPC is extremely rare. Only one case of breast cancer following liposarcoma (LP) was previously reported in a female patient. We report the first case of MBC following LP.

Case presentation

A non-smoker male patient with a history of a well-differentiated liposarcoma was treated surgically and with radiotherapy 14 years ago with no signs of recurrence. The patient presented with a left breast mass; The excisional biopsy showed poorly differentiated grade III invasive ductal carcinoma. The patient underwent a mastectomy with axillary node resection and the final diagnosis was invasive ductal carcinoma stage IIA [T:2, N:0, M:0]. The tumor markers reported; Positive Estrogen Receptor (ER+), negative Progesterone Receptor (PR-), and negative Human Epidermal Receptor (HER-). He received eight sessions of chemotherapy with Docetaxel and 16 fractions of radiotherapy. The follow-up showed no signs of recurrence.

Discussion

Despite the rarity of diagnosis MBC as a second primary. Studies have found a relation between different types of breast cancer in male patients, and further, a relation was also found between MBC and lymphoma. While no studies that link MBC and LP were previously reported.

Conclusion

We found that acquiring a treated LP would not affect the MBC prognosis or its response to treatment, yet further studies are needed to confirm this outcome.

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Multiple primary cancers occur in 2.4–17% of all people.

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The diagnosis of male breast cancer as a second primary is rare.

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Having male breast cancer following liposarcoma is even rarer.

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Well treated liposarcoma would not affect male breast cancer prognosis.

Circular RNA MTO1 intercorrelates with microRNA-630, both associate with Enneking stage and/or pathological fracture as well as prognosis in osteosarcoma patients

Objective

Circular RNA‐mitochondrial tRNA translation optimization 1 (circ‐MTO1) not only involves in bioprocess of various cancers, but also regulates osteosarcoma progression by regulating microRNA‐630 (miR‐630). However, the clinical role of circ‐MTO1 and miR‐630 in osteosarcoma is still obscure. This study aimed to assess the correlation of circ‐MTO1 and miR‐630 with disease features and prognosis and to explore their association with each other in osteosarcoma patients.

Methods

Forty‐four osteosarcoma patients who received neoadjuvant chemotherapy to surgical resection were analyzed in this retrospective study. Then, circ‐MTO1 and miR‐630 expressions were evaluated in tumor and adjacent non‐tumor specimens by reverse transcription quantitative polymerase chain reaction.

Results

Circ‐MTO1 was lower in tumor than in non‐tumor tissues (p<0.001); meanwhile, its elevated tumor expression was correlated with less advanced Enneking stage (p=0.049), good neoadjuvant chemotherapy response (p=0.029), and longer disease‐free survival (DFS) (p=0.047). However, no association was found between circ‐MTO1 and overall survival (OS) (p=0.122). Additionally, miR‐630 in tumor was higher than in non‐tumor tissues (p<0.001), while its raised tumor expression was associated with pathological fracture occurrence (p=0.003), advanced Enneking stage (p=0.036), poor neoadjuvant chemotherapy response (p=0.035), and shorter DFS (p=0.011). However, no association was found between miR‐630 and OS (p=0.066). In addition, tumor circ‐MTO1 was negatively associated with miR‐630 (r=−0.323, p=0.032).

Conclusion

Circ‐MTO1 and miR‐630 expressions are inter‐correlated and dysregulated in osteosarcoma patients. Besides, they associate with Enneking stage and/or pathological fracture, as well as neoadjuvant treatment response and accumulating DFS in these patients.

The Conundrum of Dual Primary Malignancies: Four Years’ Experience of a Single Tertiary Care Institute in India

Background: Encountering more than one malignancy in a cancer patient is no longer uncommon; this increasing incidence is mostly attributable to the improvements in life expectancy, awareness, and diagnostic facilities. This article aims to highlight this institute’s experience in diagnosis and treatment of patients of multiple primary malignancies and a comprehensive review of literature. Materials and Methods: This is a descriptive study of retrospectively collected data of a single institution over 4 years from 2013 to 2016. Known cases of cancer who were diagnosed with a second primary malignancy were included in the study. Various details such as age, sex, site of disease, temporal relation of two cancers (synchronous or metachronous), family history, tobacco use, treatment given, and survival at 1 year were recorded, organized in a tabular form, analyzed, and described. Results: A total of 29 cases of dual malignancies comprising 0.74% of a total of 3879 patients of cancer were encountered. Seventy-two percent of the cases were metachronous and 5 years was the mean time interval between tumors. There was a female preponderance, and the average age was 56 years. Breast was the most common site of malignancy. At 1 year from diagnosis of second primary, 69% of the patients were alive and 27% were disease-free. Conclusion: Second primary in a patient of cancer is becoming increasingly common and the suspicion of the same should always be borne in mind during follow-up. Prognosis as well as intent of treatment depends on respective stages of the two malignancies.

MicroRNA-504 modulates osteosarcoma cell chemoresistance to cisplatin by targeting p53

Chemoresistance implicates the therapeutic value of cisplatin and remains a primary obstacle to its clinical use. MicroRNAs (miRs) negatively modulate the expression of their target genes and are associated with the occurrence and progression of various types of tumor. The abnormal expression of miR-504 has been reported in certain types of human tumor and has been associated with tumor prognosis. However, the association between miR-504 and cisplatin in human osteosarcoma remains unclear. The present study therefore aimed to assess the in vitro effects and possible mechanism of miR-504 in cell proliferation, apoptosis and cisplatin resistance in MG63 osteosarcoma cells. The results demonstrated that miR-504 was overexpressed in osteosarcoma tissues and cells. This overexpression also induced cell proliferation, as determined by MTT and EdU staining assays. Furthermore, miR-504 suppressed cisplatin-induced apoptosis, which was demonstrated via MTT, cell morphology analysis and flow cytometry. Cisplatin-induced G₁ arrest was also suppressed, which was determined by flow cytometry. The potential target genes of miR-504 were predicted using bioinformatics. p53 was confirmed to be a direct target of miR-504 using a luciferase reporter assay and western blot analysis revealed that miR-504 negatively regulated p53 expression at a molecular level. These results indicate that miR-504 contributes to cisplatin resistance in MG63 osteosarcoma cells by suppressing p53. miR-504 may therefore be a potential biomarker for cisplatin resistance in patients with osteosarcoma.

Genetic determinants of childhood and adult height associated with osteosarcoma risk

BACKGROUND

Although increased height has been associated with osteosarcoma risk in previous epidemiologic studies, to the authors' knowledge the relative contribution of stature during different developmental timepoints remains unclear. Furthermore, the question of how genetic determinants of height impact osteosarcoma etiology remains unexplored. Genetic variants associated with stature in previous genome-wide association studies may be biomarkers of osteosarcoma risk.

METHODS

The authors tested the associations between osteosarcoma risk and polygenic scores for adult height (416 variants), childhood height (6 variants), and birth length (5 variants) in 864 osteosarcoma cases and 1879 controls of European ancestry.

RESULTS

Each standard deviation increase in the polygenic score for adult height, corresponding to a 1.7-cm increase in stature, was found to be associated with a 1.10-fold increase in the risk of osteosarcoma (95% confidence interval [95% CI], 1.01-1.19; P =.027). Each standard deviation increase in the polygenic score for childhood height, corresponding to a 0.5-cm increase in stature, was associated with a 1.10-fold increase in the risk of osteosarcoma (95% CI, 1.01-1.20; P =.023). The polygenic score for birth length was not found to be associated with osteosarcoma risk (P =.11). When adult and childhood height scores were modeled together, they were found to be independently associated with osteosarcoma risk (P =.037 and P = .043, respectively). An expression quantitative trait locus for cartilage intermediate layer protein 2 (CILP2), rs8103992, was significantly associated with osteosarcoma risk after adjustment for multiple comparisons (odds ratio, 1.35; 95% CI, 1.16-1.56 [P = 7.93×10-5 and Padjusted =.034]).

CONCLUSIONS

A genetic propensity for taller adult and childhood height attainments contributed independently to osteosarcoma risk in the current study data. These results suggest that the biological pathways affecting normal bone growth may be involved in osteosarcoma etiology.

Inhibition of LCMR1 and ATG12 by demethylation-activated miR-570-3p is involved in the anti-metastasis effects of metformin on human osteosarcoma

Epidemiological studies have demonstrated that metformin could mitigate the progression of several tumors. Although it has been proved that metformin could cause demethylation of DNA and lead to up-regulation of some encoding genes and non-coding RNAs, there is little data about the effects of metformin on metastasis, and the interaction between metastasis and autophagy in human osteosarcoma cells. Here, we found miR-570-3p was significantly down-regulated in human metastatic osteosarcoma tissues but not in non-metastatic osteosarcoma tissues. Metformin attenuates the metastasis and autophagy in osteosarcoma. Interestingly, this autophagy favors osteosarcoma cells invasion. Moreover, reduction of metformin-induced inhibition of autophagy could reverse the invasion suppression in osteosarcoma. Mechanistically, metformin increases miR-570-3p by the demethylation of DNA, and the upregulation of miR-570-3p repressed the translation of its target, LCMR1 and ATG12. Our results, for the first time, presents evidence that the miR-570-3p-mediated suppression of LCMR1 and ATG12 is involved in the metformin-induced inhibition of metastasis in osteosarcoma cells.

Triple primary malignancies of surface osteosarcoma of jaw, myelodysplastic syndrome and colorectal cancer as a second primary cancer detected by PET2-[18F]-fluoro-2-deoxy-D-glucose positron emission tomography: A case report

Second primary malignancy (SPM) is a severe issue for cancer survivors, particularly for osteosarcoma (OS) survivors. To date, the associations between subsequent SPM and OS have been well reported. Hematogenic and solid malignancies tend to occur following OS treatment. Reportedly, 2-[¹⁸F]-fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) is mainly used in OS patients for initial cancer staging, to evaluate the response of neoadjuvant chemotherapy, and when recurrence or metastasis is clinically suspected. The present case report describes a 70-year-old man diagnosed with three primary malignancies: jaw OS, myelodysplastic syndrome and colorectal adenocarcinoma. To the best of our knowledge, this combination of malignancies has not been reported previously. Until now, there is no specific protocol of postoperative FDG-PET for OS patients. Few studies have described OS follow-up methods; therefore, there is no consensus on proper follow-up methods. In the present case report, the colorectal early-stage SPM was observed, without any symptoms, by FDG-PET/computed tomography. To avoid overlooking solid SPMs, it is suggested that FDG-PET should be performed in the long-term follow-up of OS patients.

Predicting novel genes and pathways associated with osteosarcoma by using bioinformatics analysis

This aim of this study was to explore novel biomarkers related to osteosarcoma. The mRNA expression profile GSE41293 dataset was downloaded from the Gene Expression Omnibus (GEO) database, which included seven osteosarcoma and six control samples. After preprocessing, the FASTQ format reads of 13 samples were mapped to the reference sequences to screen for unique mapping reads. Differentially expressed genes (DEGs) were selected, which were then used for pathway and protein-protein interaction (PPI) network analyses. Moreover, the microarray data GSE63631 were downloaded from GEO database to verify our results. The percentages of unique mapping reads for osteosarcomas and control samples were both >85%. A total of 6157 DEGs were identified between the two groups. DEGs that were upregulated were significantly enriched in 19 pathways, and those that were downregulated were enriched in 14 pathways. In the PPI network, DEGs such as SRC, ERBB2, and CAV3 in cluster 1 were enriched in the pathway responsible for focal adhesions. The DEGs in cluster 2, such as CDK4 and CDK6, were enriched in the cell cycle pathway. In GSE63631, DEGs were significantly enriched in focal adhesion pathway, which was in accordance with the result in GSE41293. Thus, the focal adhesion and cell cycle pathways may play important roles in osteosarcoma progression, and SRC, ERBB2, CAV3, CDK4, and CDK6 may be used as critical biomarkers of osteosarcoma.

Multiple primary tumours: challenges and approaches, a review

When in a patient more than one tumour in the same or a different organ is diagnosed, multiple primary tumours may be present. For epidemiological studies, different definitions of multiple primaries are used with the two main definitions coming from the project Surveillance Epidemiology and End Results and the International Association of Cancer Registries and International Agency for Research on Cancer. The differences in the two definitions have to be taken into consideration when reports on multiple primaries are analysed. In this review, the literature on multiple primaries is reviewed and summarised. Overall, the frequency of multiple primaries is reported in the range of 2-17%. Aetiological factors that may predispose patients to multiple primaries can be grouped into host related, lifestyle factors and environmental influences. Some of the most common cancer predisposition syndromes based on a clinical presentation are discussed and the relevant genetic evaluation and testing are characterised. Importantly, from a clinical standpoint, clinical situations when multiple primaries should be suspected and ruled out in a patient are discussed. Furthermore, general principles and possible treatment strategies for patients with synchronous and metachronous multiple primary tumours are highlighted.

[Hereditary bone tumors]

Hereditary bone tumors are rare and result from mutations affecting cell cycle regulation (e.g. retinoblastoma syndrome/RB1 and Li-Fraumeni syndrome/TP53, Gardner syndrome/APC), energy metabolism (enchondromatosis/IDH1/2), complex signaling cascades (multiple hereditary exostoses/EXT1/2) and DNA integrity (Rothmund-Thomson/RECQL4, Werner/WRN and Bloom syndromes/BLM). The majority of syndromes are incompletely understood and can lead to multiple benign tumors, of which some might undergo secondary malignant transformation over time (enchondromatosis: enchondromas, multiple hereditary exostoses: osteochondromas, Gardner syndrome: osteomas) or bone sarcomas, primarily osteosarcomas as primary (Li-Fraumeni, Rothmund-Thomson, Werner and Bloom syndromes) or secondary manifestation (retinoblastoma syndrome) of the disease. Some syndromes additionally predispose to the development of a variety of other malignant tumors during life. Compared to sporadically occurring tumors, syndrome-related neoplasms can differ in the time of manifestation, site and histology, which can help in recognizing a specific tumor predisposition syndrome.

Investigation on the role of VEGF gene polymorphisms in the risk of osteosarcoma

OBJECTIVE

The VEGF in low oxygen conditions are reported to prolong the survival of malignant cell, and thus this gene has a critical role in tumor growth and invasion as well as development of malignant tumor. We aimed to assess the association between the six common SNPs and the risk of osteosarcoma, and their association with environmental factors.

METHODS

176 subjects with osteosarcoma and 176 gender- and sex-matched healthy control individuals were enrolled into our study. The VEGF -2578C/A, -1156G/A, +1612G/A, +936C/T, -634G/C and -460T/C gene polymorphisms were determined using a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay according to manufacturer's instructions.

RESULTS

By conditional logistic regression analysis, AA and CA+AA genotypes of VEGF -2578C/A were associated with significant increased risk of osteosarcoma compared with CC genotype, and the ORs(95%CI) were 2.32(1.18-4.60) and 1.68(1.07-2.64), respectively. Moreover, individuals with CC and TC+CC genotypes of VEGF-460T/C had significant increased risk of osteosarcoma compared with those carrying with the TT genotype, and ORs(95%CI) were 2.15(1.10-4.21) and 1.60(1.0-2.58), respectively. By stratified analysis, we did not find statistically significant associated between VEGF -2578C/A and -460T/C gene polymorphisms and cancer risk by stratification analysis.

CONCLUSION

Our results suggested that VEGF -2578C/A and -460T/C gene polymorphisms may be association with an increased risk of osteosarcoma.

Fourth primary malignant tumor in a patient with possible li-fraumeni syndrome: synchronous diagnosis of postirradiation sarcoma, cutaneous relapse of a previous soft tissue sarcoma, and lung adenocarcinoma

We present a 46-year-old female patient who is diagnosed with synchronous postirradiation sarcoma, cutaneous relapse of a previous soft tissue sarcoma, and lung adenocarcinoma. More than one malignant tumor at the same time with an accompanying relapse of a previous malignant tumor is a rare entity. A relatively young patient diagnosed with adenocarcinoma of the urethra before age 40, which is an unusual tumor for that age, later three more different malignant tumors being diagnosed, two of which are synchronous, causes the suspicion of Li-Fraumeni syndrome.

Associations of polymorphisms in the bone morphogenetic protein-2 gene with risk and prognosis of osteosarcoma in a Chinese population

Osteosarcoma is the most common type of bone cancer in adolescence. Bone morphogenetic protein-2 (BMP-2) plays important roles in the development of bone and cartilage and in inhibiting the tumorigenicity of cancer stem cells in human osteosarcoma cell line. The aim of this study was to examine whether polymorphisms in the BMP2 gene are associated with osteosarcoma risk and prognosis in Chinese population. Five single nucleotide polymorphisms (SNP) in the BMP2 gene were genotyped in a case-control study, including 203 osteosarcoma patients and 406 cancer-free controls. We found that rs3178250 TT genotype was associated with significant increased osteosarcoma risk (age-adjusted odds ratio (OR) = 2.06, 95% confidence intervals (CI) of 1.23-3.45) compared with CC genotype. Subjects carrying the AA genotype of rs1005464 had significant decreased cancer risk (age-adjusted OR = 0.44, 95% CI of 0.23-0.85) compared with those carrying the GG genotype. Haplotype analysis also showed that carriers of the G-T-T-G and A-T-T-G haplotypes (rs235764-rs3178250-rs235768-rs1005464) had significant increased risks of osteosarcoma (age-adjusted OR = 1.85, 95% CI of 1.28-2.66 and age-adjusted OR = 1.51, 95% CI of 1.06-2.16) compared with the G-C-T-A haplotype carriers. Besides, rs1005464 was an independent prognostic factor for osteosarcoma patients (GA vs. GG: age-adjusted hazard radio (HR) = 0.60, 95% CI of 0.36-0.99). Our data suggest that genetic mutations in the BMP2 gene are associated with osteosarcoma risk and prognosis in a Chinese population.

A Rb1 promoter variant with reduced activity contributes to osteosarcoma susceptibility in irradiated mice

BACKGROUND

Syndromic forms of osteosarcoma (OS) account for less than 10% of all recorded cases of this malignancy. An individual OS predisposition is also possible by the inheritance of low penetrance alleles of tumor susceptibility genes, usually without evidence of a syndromic condition. Genetic variants involved in such a non-syndromic form of tumor predisposition are difficult to identify, given the low incidence of osteosarcoma cases and the genetic heterogeneity of patients. We recently mapped a major OS susceptibility QTL to mouse chromosome 14 by comparing alpha-radiation induced osteosarcoma in mouse strains which differ in their tumor susceptibility.

METHODS

Tumor-specific allelic losses in murine osteosacoma were mapped along chromosome 14 using microsatellite markers and SNP allelotyping. Candidate gene search in the mapped interval was refined using PosMed data mining and mRNA expression analysis in normal osteoblasts. A strain-specific promoter variant in Rb1 was tested for its influence on mRNA expression using reporter assay.

RESULTS

A common Rb1 allele derived from the BALB/cHeNhg strain was identified as the major determinant of radiation-induced OS risk at this locus. Increased OS-risk is linked with a hexanucleotide deletion in the promoter region which is predicted to change WT1 and SP1 transcription factor-binding sites. Both in-vitro reporter and in-vivo expression assays confirmed an approx. 1.5 fold reduced gene expression by this promoter variant. Concordantly, the 50% reduction in Rb1 expression in mice bearing a conditional hemizygous Rb1 deletion causes a significant rise of OS incidence following alpha-irradiation.

CONCLUSION

This is the first experimental demonstration of a functional and genetic link between reduced Rb1 expression from a common promoter variant and increased tumor risk after radiation exposure. We propose that a reduced Rb1 expression by common variants in regulatory regions can modify the risk for a malignant transformation of bone cells after radiation exposure.

The synergistic anticancer effect of artesunate combined with allicin in osteosarcoma cell line in vitro and in vivo

BACKGROUND

Artesunate, extracted from Artemisia annua, has been proven to have anti-cancer potential. Allicin, diallyl thiosulfinate, the main biologically active compound derived from garlic, is also of interest in cancer treatment research. This object of this report was to document synergistic effects of artesunate combined with allicin on osteosarcoma cell lines in vitro and in vivo.

METHODS

After treatment with artesunate and allicin at various concentrations, the viability of osteosarcoma cells was analyzed by MTT method, with assessment of invasion and motility, colony formation and apoptosis. Western Blotting was performed to determine the expression of caspase-3/9, and activity was also detected after drug treatment. Moreover, in a nude mouse model established with orthotopic xenograft tumors, tumor weight and volume were monitored after drug administration via the intraperitoneal (i.p.) route.

RESULTS

The viability of osteosarcoma cells in the combination group was significantly decreased in a concentration and time dependent manner; moreover, invasion, motility and colony formation ability were significantly suppressed and the apoptotic rate was significantly increased through caspase-3/9 expression and activity enhancement in the combination group. Furthermore, suppression of tumor growth was evident in vivo.

CONCLUSION

Our results indicated that artesunate and allicin in combination exert synergistic effects on osteosarcoma cell proliferation and apoptosis.

Osteosarcoma treatment - where do we stand? A state of the art review

Long-term outcome for patients with high-grade osteosarcoma has improved with the addition of systemic chemotherapy, but subsequent progress has been less marked. Modern, multiagent, dose-intensive chemotherapy in conjunction with surgery achieves a 5-year event-free survival of 60-70% in extremity localized, non-metastatic disease. A major, as yet unsolved, problem is the poor prognosis for metastatic relapse or recurrence, and for patients with axial disease. This article reviews the current state of the art of systemic osteosarcoma therapy by focusing on the experiences of cooperative osteosarcoma groups. Also, we shed light on questions and challenges posed by the aggressiveness of the tumor, and we consider potential future directions that may be critical to progress in the prognosis of high-grade osteosarcoma.

Understanding the Biology of Bone Sarcoma from Early Initiating Events through Late Events in Metastasis and Disease Progression

The two most common primary bone malignancies, osteosarcoma (OS), and Ewing sarcoma (ES), are both aggressive, highly metastatic cancers that most often strike teens, though both can be found in younger children and adults. Despite distinct origins and pathogenesis, both diseases share several mechanisms of progression and metastasis, including neovascularization, invasion, anoikis resistance, chemoresistance, and evasion of the immune response. Some of these processes are well-studies in more common carcinoma models, and the observation from adult diseases may be readily applied to pediatric bone sarcomas. Neovascularization, which includes angiogenesis and vasculogenesis, is a clear example of a process that is likely to be similar between carcinomas and sarcomas, since the responding cells are the same in each case. Chemoresistance mechanisms also may be similar between other cancers and the bone sarcomas. Since OS and ES are mesenchymal in origin, the process of epithelial-to-mesenchymal transition is largely absent in bone sarcomas, necessitating different approaches to study progression and metastasis in these diseases. One process that is less well-studied in bone sarcomas is dormancy, which allows micrometastatic disease to remain viable but not growing in distant sites – typically the lungs – for months or years before renewing growth to become overt metastatic disease. By understanding the basic biology of these processes, novel therapeutic strategies may be developed that could improve survival in children with OS or ES.

Two Metachronous Neoplasms in the Radiotherapy Fields of a Young Man With Familial Adenomatous Polyposis

BACKGROUND

It is recognized that various radiation-induced malignancies often follow childhood radiotherapy. Radiation-induced neoplasms have been shown to occur with increased frequency in syndromes due to mutated tumor suppressor genes. There exist no recommendations for the management of cancer patients with germline APC gene mutations. Preclinical data suggest that APC gene mutations cause enhanced radiosensitivity, but no clinical observations exist that show that patients with this mutation are at higher risk for radiation-induced malignancies.

RESULTS

We report the case of a 32-year-old man with a genetic diagnosis of familial adenomatous polyposis (FAP) who initially presented at age 10 with a medulloblastoma treated with radiotherapy and surgery. Radiation-induced papillary thyroid carcinoma followed 13 years later. Finally, radiation-induced soft tissue osteosarcoma occurred with widespread metastasis 20 years thereafter.

CONCLUSIONS

This is the first report of 2 malignancies in the prior radiotherapy fields of a patient with a genetic diagnosis of FAP. More important, this suggests that APC-defective cells are at an enhanced sensitivity to the carcinogenic effects of radiotherapy compared with APC-proficient cells. This could argue for genetic screening in affected members of these families and for creation of treatment recommendations to more seriously consider the risks of radiation therapy.

Taurine chloramine induces apoptosis in human osteosarcoma cell lines

Although combination of surgery with chemotherapy has noticeably improved the survival rate of osteosarcoma patients, the application of anticancer drugs is still associated with significant adverse reactions, for instance acquisition of drug-resistant phenotypes, necessitating the development of new chemotherapeutical agents. Therefore, the aim of this study was to research, if taurine chloramine (NCT) induces apoptosis in the osteosarcoma cell lines HOS, MG-63, and SAOS-2. Proliferation of osteosarcoma cells was detected with the "EZ4U Cell Proliferation and Cyotoxicity Assay" showing a time- and dose-dependent cytotoxic effect of NCT on these cell lines. After 3 h of incubation all cell lines showed significantly less cells at 5.5 mM NCT solutions, after 6 h at concentrations of 1.1 and 2.2 mM. Acridine-orange fluorescence nuclear staining showed characteristic features of apoptosis. DNA fragmentation was detected via ELISA, showing significant results for HOS and MG-63 after 6 h at an NCT concentration of 3.3 mM. Results of JC-1 mitochondrial FACS analysis presented a significant increase in apoptotic cells after 6 h at 3.3 mM for the tested cell lines. Summarized, the results of this study indicate that NCT is a promising agent in osteosarcoma therapy.

MicroRNA Involvement in Osteosarcoma

Osteosarcoma (OS) is the most common primary malignant bone tumor, usually arising in the long bones of adolescents and young adults. While our knowledge of the molecular pathogenesis of OS has increased in recent years, we are still far from a comprehensive understanding of the molecular mechanisms of the disease, such as its tumorigenesis, specific mediators of disease progression, occurrence of chemoresistance, and development of metastasis. After the recent discovery of microRNAs (miRNAs), their critical roles in molecular biological processes have been of great interest in the cancer research field, including research on sarcomas. MiRNAs are highly conserved noncoding RNAs which play important roles as oncogenic or suppressive genes to simultaneously regulate multiple targets. Recent genome-wide screening using miRNA expression profiles has identified specific miRNA expression patterns that are associated with the biological and clinical properties of cancers. Additionally, miRNAs and their target genes or proteins can be potential novel biomarkers or therapeutic targets for cancer. However, there are several challenges that must be addressed in order to translate miRNA-based therapeutics to the clinical setting. In this review, we summarize the current understanding of the roles that miRNAs play in OS, and highlight their potential as biomarkers or therapeutic targets.

At-risk populations for osteosarcoma: the syndromes and beyond

Osteosarcoma is the most common primary malignancy of bone. Most cases are sporadic without a known genetic or environmental cause. Heritable genetic predisposition syndromes are associated with a small percentage of osteosarcomas. Study of these rare disorders has provided insight into the molecular pathogenesis of osteosarcoma. Screening of at-risk families and surveillance of affected individuals for these syndromes may permit earlier diagnosis and more effective treatment of osteosarcoma in these populations. This paper reviews the genetic and clinical features of the known osteosarcoma predisposition syndromes.

Multicentric osteosarcoma: clinicopathologic and radiographic study of 56 cases

Multicentric osteosarcoma (M-OGS) is characterized by multicentricity of osseous osteosarcomas, either synchronous or metachronous, without visceral involvement. The study's purpose was to clinicopathologically and radiographically analyze 56 cases of M-OGS (22 synchronous and 34 metachronous). The distal femur was the most common site. Histologically, all tumors were high grade. Of 22 patients with synchronous M-OGS, 16 had 3 or more simultaneous tumors; the axial skeleton was involved in 14 (64%) of 22 cases. In metachronous M-OGS, the second malignancy occurred after a median of 22 months. Treatment was surgery, chemotherapy, radiotherapy, or a combination of these. Patients with metachronous osteosarcoma had a median survival longer than did patients with synchronous tumors. Overall, 8 long-term survivors were treated by aggressive surgery with wide margins (plus chemotherapy and/or radiotherapy). M-OGS combines multiple skeletal locations of high-grade conventional osteosarcomas and has a poor prognosis. Aggressive surgery may result in improved long-term survival, particularly in patients with metachronous disease.

Targeted therapies in bone sarcomas: current approach and future directions

INTRODUCTION

Bone sarcomas are rare malignancies and once advanced, there is limited response to current chemotherapeutic regimens. Targeted therapies could have substantial impact on these diseases.

AREAS COVERED

Specific molecular targets of bone sarcomas are reviewed along with the various targeted therapies that have potential to change the outcome of these chemotherapy resistant diseases.

EXPERT OPINION

There are promising pathways identified that targeted inhibitors could provide better treatment options for metastatic bone sarcomas. There is a strong need for continued Phase II and III clinical trials investigating these molecularly targeted therapies.

The molecular pathogenesis of osteosarcoma: a review

Osteosarcoma is the most common primary malignancy of bone. It arises in bone during periods of rapid growth and primarily affects adolescents and young adults. The 5-year survival rate for osteosarcoma is 60%-70%, with no significant improvements in prognosis since the advent of multiagent chemotherapy. Diagnosis, staging, and surgical management of osteosarcoma remain focused on our anatomical understanding of the disease. As our knowledge of the molecular pathogenesis of osteosarcoma expands, potential therapeutic targets are being identified. A comprehensive understanding of these mechanisms is essential if we are to improve the prognosis of patients with osteosarcoma through tumour-targeted therapies. This paper will outline the pathogenic mechanisms of osteosarcoma oncogenesis and progression and will discuss some of the more frontline translational studies performed to date in search of novel, safer, and more targeted drugs for disease management.

p53-targeted cancer pharmacotherapy: move towards small molecule compounds

OBJECTIVES

For the past three decades of research, p53 has been identified as one of the most targetable molecules for developing anticancer treatments. This tumour suppressor protein is involved in apoptosis, cell cycle arrest and senescence. A wide range of pharmaceutical drugs and radiotherapy treatments activate this protein and rely on p53 signalling for therapeutic outcome. Promising small molecular weight compounds, some of which are undergoing clinical trials, are discussed in this review.

KEY FINDINGS

The spectrum of potential therapeutic approaches trialled for p53 stretch from gene therapy to the more recent development of small molecules capable of activating wild-type p53 or reactivating mutant p53.

SUMMARY

Our ever-growing knowledge leads us to better understand this protein, from its structure and activities to its potential therapeutic application, firstly for cancer and then for other diseases and maybe even for reversal of ageing.

Twenty years of follow-up of survivors of childhood osteosarcoma: a report from the Childhood Cancer Survivor Study

BACKGROUND

Osteosarcoma survivors have received significant chemotherapy and have undergone substantial surgeries. Their very long-term outcomes (20 year) are reported here.

METHODS

The authors assessed the long-term outcomes of 733 5-year survivors of childhood osteosarcoma diagnosed from 1970 to 1986 to provide a comprehensive evaluation of medical and psychosocial outcomes for survivors enrolled in the Childhood Cancer Survivor Study (CCSS). Outcomes evaluated included overall survival, second malignant neoplasms (SMNs), recurrent osteosarcoma, chronic health conditions, health status (general and mental health and functional limitations), and psychosocial factors. Outcomes of osteosarcoma survivors were compared with general-population statistics, other CCSS survivors, and CCSS siblings.

RESULTS

Survivors had a mean follow-up of 21.6 years. The overall survival of children diagnosed with osteosarcoma who survived 5 years at 20 years from original diagnosis was 88.6% (95% confidence interval [CI], 86.6%-90.5%). The cumulative incidence of SMNs at 25 years was 5.4%, with a standardized incidence ratio of 4.79 (95% CI, 3.54-6.33; P<.01). Overall, 86.9% of osteosarcoma survivors experienced at least 1 chronic medical condition, and >50% experienced ≥2 conditions. Compared with survivors of other cancers, osteosarcoma survivors did not differ in their reported general health status (odds ratio [OR], 0.9; 95% CI, 0.7-1.2), but were more likely to report an adverse health status in at least 1 domain (OR, 1.9; 95% CI, 1.6-2.2), with activity limitations (29.1%) being the most common.

CONCLUSIONS

Childhood osteosarcoma survivors in this cohort did relatively well, considering their extensive treatment, but are at risk of experiencing chronic medical conditions and adverse health status. Survivors warrant life-long follow-up.

[Hereditary bone tumors]

Familial diseases leading to bone tumor formation are rare. They are mainly caused by genetic alterations of cell cycle constituent genes, such as retinoblastoma syndrome (RB1) and Li-Fraumeni syndrome (p53), of genes involved in growth-regulating transcriptional cascades, such as enchondromatosis (PTHR1) and multiple hereditary exostoses (EXT1, EXT2) or of genes maintaining chromosomal stability, such as Rothmund-Thomson (RECQL4), Werner (WRN) and Bloom syndromes (BLM). This leads to multiple benign bone tumors, which may undergo secondary malignant transformation (enchondromatosis: enchondromas, multiple hereditary exostoses: osteochondromas) or bone sarcomas, mainly osteosarcomas, such as primary (Li-Fraumeni, Rothmund-Thomson, Werner and Bloom syndromes) or secondary manifestations (retinoblastoma syndrome) of the underlying disease. Some of these lesions also carry an increased risk for developing additional malignant diseases. In contrast to sporadically occurring similar tumors, differences in manifestation in time, topography or histology may be present which can aid in the correct recognition of the underlying syndrome.

Secondary acute myeloid leukemia after successful treatment for osteosarcoma

Secondary acute myeloid leukemia (sAML) is a rare complication following chemotherapy for osteogenic sarcoma. However, the exact offending drug is difficult to prove as there is no consistent data. It usually develops 2 years after completion of therapy. We report a case of sAML that developed within 8 months of completing the treatment. The patient was treated with cisplatin, doxorubicin and high-dose methotreaxate followed by surgery (amputation). Eight months after completion of therapy, while on follow-up, he presented with leukocytosis and thrombocytopenia and confirmed to have AML.

Microarray analysis identifies distinct gene expression profiles associated with histological subtype in human osteosarcoma

Osteosarcoma is the most common primary malignant bone tumour. Currently osteosarcoma classification is based on histological appearance. It was the aim of this study to use a more systematic approach to osteosarcoma classification based on gene expression analysis and to identify subtype specific differentially expressed genes. We analysed the global gene expression profiles of ten osteosarcoma samples using Affymetrix U133A arrays (five osteoblastic and five non-osteoblastic osteosarcoma patients). Differential gene expression analysis yielded 75 genes up-regulated and 97 genes down-regulated in osteoblastic versus non-osteoblastic osteosarcoma samples, respectively. These included genes involved in cell growth, chemotherapy resistance, angiogenesis, steroid- and neuropeptide hormone receptor activity, acute-phase response and serotonin receptor activity and members of the Wnt/ß-catenin pathway and many others. Furthermore, we validated the highly differential expression of six genes including angiopoietin 1, IGFBP3, ferredoxin 1, BMP, decorin, and fibulin 1 in osteoblastic osteosarcoma relative to non-osteoblastic osteosarcoma. Our results show the utility of gene expression analysis to study osteosarcoma subtypes, and we identified several genes that may play a role as potential therapeutic targets in the future.

Secondary supratentorial primitive neuroectodermal tumor following treatment of childhood osteosarcoma

A 16-year-old Caucasian male was diagnosed with a primitive neuroectodermal tumor (PNET) 5 years following the diagnosis of nonmetastatic osteosarcoma of the left proximal humerus. The patient was initially treated with standard chemotherapy and limb salvage resection for osteosarcoma. Nine months after the completion of therapy, he developed lung metastases for which he underwent surgical resection and received additional chemotherapy. Almost 5 years after the osteosarcoma diagnosis, the patient was diagnosed with a supratentorial PNET, which represents the first known case reported in a patient with osteosarcoma.

Risedronate inhibits human osteosarcoma cell invasion

BACKGROUND

Osteosarcoma is a highly malignant bone tumor and is the most commonly encountered malignant bone tumor in children and adolescents. Furthermore, significant numbers of patients eventually develop pulmonary metastases and succumb to the disease even after conventional multi-agent chemotherapy and surgical excision. Several solid tumors display enhanced expression of matrix metalloproteinases (MMPs), and recently clinical trials have been initiated on MMP-inhibitors. On the other hand, bisphosphonates (BPs), which have a profound effect on bone resorption, are widely used to treat osteoclast-mediated bone diseases. BPs are also known to inhibit tumor growths and metastases in some tumors such as breast cancer, renal cell carcinoma, and prostate cancer.

METHODS

Two osteosarcoma cell lines (SaOS-2 and U2OS) were treated with risedronate (0, 0.1, 1, 10 microM) for 48 hours. Cell viabilities were determined using MTT assay, the mRNA levels of MMP-2 and MMP-9 were analyzed by reverse-transcription polymerase chain reaction, the amount of MMP-2 and MMP-9 protein were analyzed by Westernblot, the activities of MMP-2 and MMP-9 were observed by Gelatin zymography, and Matrigel invasion assays were used to investigate the invasive potential of osteosarcoma cell lines before and after risedronate treatment.

RESULTS

The invasiveness of osteosarcoma cell lines (SaOS-2, U2OS) were reduced in a dose dependent manner follow 48 hour treatment of up to 10 microM of the risedronate at which concentration no cytotoxicity occurred. Furthermore, the gelatinolytic activities and protein and mRNA levels of MMP-2 and MMP-9 were also suppressed by increasing risedronate concentrations.

CONCLUSION

Given that MMP-2 and MMP-9 are instrumental in tumor cell invasion, our results suggest the risedronate could reduce osteosarcoma cell invasion.

Secondary thyroid papillary carcinoma in osteosarcoma patients: report of two cases

We report two cases of papillary thyroid carcinoma occurring after the successful treatment of osteosarcoma. One of the patients was administered with several alkylating agents and topoisomerase II inhibitor as part of the primary treatment of osteosarcoma. The onset of thyroid carcinoma occurred after 5 and 12 yr after cessation of the osteosarcoma therapy. All the patients involved in this study are alive and free of their malignancies. There have been eight case reports of these two malignancies occurring in the same patient. Thyroid carcinoma rarely occurs in patients with osteosarcoma; however, vigilant surveillance and long-term follow-up should be emphasized for all survivors.

Incidence patterns of soft tissue sarcomas, regardless of primary site, in the surveillance, epidemiology and end results program, 1978-2001: An analysis of 26,758 cases

Soft tissue sarcomas (STS) are a heterogeneous group of uncommon tumors that show a broad range of differentiation that may reflect etiologic distinction. Routine tabulations of STS are not morphology-specific. Further, the lack of inclusion of sarcomas arising in all organs in most standard evaluations underestimates the true rates. We analyzed the 1978-2001 Surveillance, Epidemiology and End Results program incidence rates of STS regardless of primary site, except bones and joints, using the 2002 criteria of the WHO classification. There were 26,758 cases available for analysis. Leiomyosarcomas accounted for 23.9%, malignant fibrous histiocytomas 17.1%, liposarcomas 11.5%, dermatofibrosarcomas 10.5%, rhabdomyosarcomas 4.6% and angiosarcomas 4.1%. Almost half (47.9%) of the sarcomas arose in the soft tissues, 14.0% in the skin and 7.0% in the uterus. Overall, incidence rates were highest among black women (6.26/100,000 woman-years) and the lowest among white women (4.60/100,000). Age-adjusted rates increased at 1.2% and 0.8% per year among white males and females, respectively, both trends statistically significant, while rates among blacks declined slightly. About 40% of leiomyosarcomas among women were uterine in origin, with a black/white rate ratio of 1.7. This rate ratio increased to 2.0 when we accounted for the lower prevalence of intact uteri among black compared to white women. Total STS rates rose exponentially with age. Rates for both uterine leiomyosarcoma and dermatofibrosarcoma increased rapidly during the childbearing years, peaking at about age 40 and 50, respectively. Incidence patterns of STS varied markedly by histologic type, supporting the notion that these tumors may be etiologically distinct.

Second malignant neoplasm in patients with osteosarcoma of the extremities treated with adjuvant and neoadjuvant chemotherapy

We evaluated the rate of second malignancies in 1205 patients with osteosarcoma of the extremity treated at our Institution with different protocols of adjuvant and neoadjuvant chemotherapy. Twenty-six patients (2.15%) developed a second malignant neoplasm at a median of 7.6 years (1 to 25 y) after primary osteosarcoma treatment. Of these, 2 developed a third cancer which were not considered in the series. Second neoplasms were leukemia (10), breast (7), lung (2), kidney (2), central nervous system cancer (2), soft tissue (1), parotid (1), and colon (1). The rate of second neoplasms was significantly higher in female patients, and the latent period shorter in hematologic tumors compared with solid tumors. Ten of these 26 patients are disease free at a median of 7.7 years (range 1 to 15 y) after the last treatment. The rate of second malignancies observed in the osteosarcoma group was significantly higher than that observed in the control group of 1160 patients with benign tumors treated in the same period at our Institute (2.2% vs. 0.8%, P<0.009). Our study showed that the risk of second neoplasm within 15 years increased and then leveled off and that although secondary solid tumors could be explained as unrelated cases, leukemias seem to be over represented.

Growth inhibition and sensitization to cisplatin by zoledronic acid in osteosarcoma cells

Since osteosarcoma is a drug-resistant disease, the aim of the present study was to explore the possible interest of therapeutic approaches including nitrogen-containing biphosphonate zoledronic acid using osteosarcoma cell lines with different genetic backgrounds. Parental p53+/pRb+ U2-OS, p53-mutant U2-OS (U2-OS/175) and p53-/pRb- SAOS were sensitive to zoledronic acid with no significant differences in IC50 values. Analysis of cell cycle distribution revealed a time-dependent shifting of U2-OS cells towards G2 phase with cell cycle arrest in G2 phase at 96 h of exposure to the compound. Conversely, U2-OS/175 and SAOS cells responded to treatment with transient cell accumulation in S phase up to 48-72 h, respectively. Cell lines were exposed to increasing concentrations of cisplatin alone or combined with sub-toxic doses of zoledronic acid. A growth inhibitory effect was seen after combined treatment in U2-OS, otherwise resistant to cisplatin up to 100 ng/ml. Zoledronic acid did not efficiently sensitized U2-OS/175 and SAOS to cisplatin, thereby suggesting that different behavior may depend on p53 mutation. This data was confirmed in U2-OS cells where p53 expression was downregulated by RNA interference. Present findings indicate occurrence of sensitization to cisplatin by zoledronic acid in wild-type p53 osteosarcoma cells but not in p53-null cells nor in cells expressing a dominant-negative form of p53, supporting that wild-type p53 is required for synergistic interaction of cisplatin and zoledronic acid.

Pathology of primary malignant bone and cartilage tumours

Bone- and cartilage-forming tumours (osteosarcomas and chondrosarcomas) are rare malignant neoplasms. These tumours are clinically aggressive and often need extensive local and/or systemic treatment. Whereas no other treatment but surgery is currently available for chondrosarcomas, osteosarcomas show an approximately 50-80% response rate to adjuvant chemotherapy. Surgical removal of these tumours is currently mostly performed with limb salvage, but amputation may be required in some cases. In addition, the tumours have a risk of local recurrences adversely affecting the prognosis compared to the primary tumour. In this report we will mainly focus on two of the most prevalent malignant bone tumours, conventional osteosarcoma and conventional chondrosarcoma, and use these to illustrate the problems with the diagnosis of bone sarcomas in general.

Multilocus inheritance determines predisposition to α-radiation induced bone tumourigenesis in mice

In a recent study, we presented evidence for genetic predisposition governing radiation osteosarcomagenesis in mice. Following the incorporation of the bone-seeking alpha emitter 227Th, approximately 25% of the variance in osteosarcoma incidence was determined by inherited genetic factors. We have now mapped 5 susceptibility loci in crosses between the more susceptible BALB/c and the more resistant CBA/Ca strains. The major QTL on chromosome 14 overlaps with a locus that was already found in our previous study, using different strains of mice. Here, we investigate the effect by which the major susceptibility locus and 4 minor modifier loci interact to influence osteosarcoma predisposition. Following incorporation of the bone-seeking isotope, 100% of mice that harbour high-risk genotypes at all 5 susceptibility loci develop osteosarcoma with an average of 472 days latency times. In 10 mice inheriting exclusively low-risk genotypes only 1 osteosarcoma was found, arising after 733 days latency time. Inheritance of distinct combinations of BALB/c and CBA/Ca alleles at the susceptibility loci confer more extreme phenotypes in terms of susceptibility or resistance than observed in either of the two parental inbred strains. From the present study, we demonstrate that additive effects of multiple alleles, each making only a minor phenotypic contribution, can combine and significantly alter tumour risk. This mechanism can be of particular importance in genetically heterogeneous populations such as man.