A case of synchronous double primary breast carcinoma and osteosarcoma: Mismatch repair genes mutations as a possible cause for multiple early onset malignant tumors

Malignant fibrous histiocytoma of the axilla with breast cancer: A case report

BACKGROUND

Multiple primary malignant neoplasms refer to multiple tumors with different origins. They may be synchronous or metachronous. The incidence is 0.73%– 11.7%. Synchronous cases of breast cancer with sarcoma are rare.

CASE SUMMARY

Here, we report a 78-year-old female patient admitted to hospital after accidental discovery of a left axillary mass. Preoperative examination revealed a breast mass. Pathology showed left breast cancer and left axillary sarcoma. The patient underwent surgery, endocrine therapy and radiotherapy. She has been followed up for 1 year, and no local recurrence or distant metastasis was observed.

CONCLUSION

Attention should be paid to multiple primary malignant neoplasms, not limited to the current diagnosis and analysis, avoiding missed diagnosis and misdiagnosis.

A Pan-Cancer Analysis on the Systematic Correlation of MutS Homolog 2 (MSH2) to a Malignant Tumor

MutS homolog 2 (MSH2) is a crucial participant in human DNA repair, and lots of the studies functionally associated with it were begun with hereditary nonpolyposis colorectal cancer (HNPCC). MSH2 has also been reported to take part in the progresses of various tumors' formation. With the help of GTEx, CCLE, and TCGA pan-cancer databases, the analysis of MSH2 gene distribution in both tumor tissues and normal control tissues was carried out. Kaplan-Meyer survival plots and COX regression analysis were conducted for the assessment into the MSH2's impact on tumor patients' clinical prognosis. In an investigation to the association of MSH2 expression with immune infiltration level of various tumors and a similar study on tumor immune neoantigens, microsatellite instability was subsequently taken. It was found that high expression of MSH2 is prevalent in most cancers. MSH2's efficacy on clinical prognosis as well as immune infiltration in tumor patients revealed a fact that expression of MSH2 in prostate adenocarcinoma (PRAD), brain lower-grade glioma (LGG), breast-invasive carcinoma (BRCA), and head and neck squamous cell carcinoma (HNSC) posed a significant correlation with the immune cell infiltration level of patients. Likewise as above, MSH2's expression comes in a similar trend with tumor immune neoantigens and microsatellite instability. MSH2's expression in the majority of tumors is a direct factor to the activation of tumor-associated pathways as well as immune-associated pathways. MSH2's early screening or even therapeutic target role for sarcoma (SARC) diagnosis is contributing to the efficiency of early screening and overall survival in SARC patients.

Mismatch repair deficiency is rare in bone and soft tissue tumors

Introduction

There has been an increased demand for mismatch repair (MMR) status testing in sarcoma patients after the success of immune checkpoint inhibition (ICI) in MMR deficient tumors. However, data on MMR deficiency in bone and soft tissue tumors is sparse, rendering it unclear if routine screening should be applied. Hence, we aimed to study the frequency of MMR deficiency in bone and soft tissue tumors after we were prompted by two (potential) Lynch syndrome patients developing sarcomas.

Methods

Immunohistochemical expression of MLH1, PMS2, MSH2 and MSH6 was assessed on tissue micro arrays (TMAs), and included 353 bone and 539 soft tissue tumors. Molecular data was either retrieved from reports or microsatellite instability (MSI) analysis was performed. In MLH1 negative cases, additional MLH1 promoter hypermethylation analysis followed. Furthermore, a systematic literature review on MMR deficiency in bone and soft tissue tumors was conducted.

Results

Eight MMR deficient tumors were identified (1%), which included four leiomyosarcoma, two rhabdomyosarcoma, one malignant peripheral nerve sheath tumor and one radiation‐associated sarcoma. Three patients were suspected for Lynch syndrome. Literature review revealed 30 MMR deficient sarcomas, of which 33% were undifferentiated/unclassifiable sarcomas. 57% of the patients were genetically predisposed.

Conclusion

MMR deficiency is rare in bone and soft tissue tumors. Screening focusing on tumors with myogenic differentiation, undifferentiated/unclassifiable sarcomas and in patients with a genetic predisposition / co‐occurrence of other malignancies can be helpful in identifying patients potentially eligible for ICI.

Breast Cancer and Multiple Primary Malignant Tumors: Case Report and Review of the Literature

Multiple primary malignant neoplasms are multiple tumors with different pathogenetic origin. They may be synchronous or metachronous. The management of these conditions represents an interesting clinical scenario. A crucial aspect is the decision regarding which tumor to treat initially, and how to schedule further treatments according to individual tumor risk. This process involves a multidisciplinary physician team to ensure favorable outcomes. We describe a case report of a female patient affected by primary synchronous tumors of the breast and pectoral skin, which raised a series of diagnostic, etiological and therapeutic issues persuading us to carry out a critical review of the literature.

Inhibitory effect of MSH6 gene silencing in combination with cisplatin on cell proliferation of human osteosarcoma cell line MG63

Osteosarcoma (OS) is one of the most common primary bone malignancies, with the survival rate of patients with OS remaining low. Therefore, we conducted this study to identify the potential role combination of both MSH6 gene silencing and cisplatin (DDP) plays in OS cell proliferation and apoptosis. Microarray-based gene expression profiling was used to identify the differentially expressed genes (DEGs) in patients with OS, as well as microRNAs (miRNAs) that regulate the candidate gene. OS tissues from 67 patients with OS along with normal tissues from 24 amputee patients were collected for detection of the positive expression of mutS homolog 6 (MSH6) protein, mRNA, and protein expressions of c-myc, cyclin D1, l-2, B-cell lymphoma 2 (Bcl-2), Stathmin, proliferating cell nuclear antigen (PCNA), and Bcl-2-associated X (Bax). Moreover, after MSH6 silencing and DDP were treated on the selected human OS cell line MG63 with the highest expression of MSH6, cell viability, cell cycle distribution, and apoptosis were detected. The microarray analysis showed that MSH6 was upregulated in OS chip data. Furthermore, silencing MSH6 combined with DDP reduced expressions of c-myc, cyclin D1, Bcl-2, Stathmin, and PCNA, and elevated Bax expression, whereas inhibiting OS cell viability, impeding cell cycle distribution, and inducing apoptosis. In conclusion, our preliminary results indicated that the combination of MSH6 gene silencing coupled with DDP may have a better effect on the inhibition of OS cell proliferation and promote apoptosis, potentially providing targets for the OS treatment.

Effects of distinct drugs on gene transcription in an osteosarcoma cell line

Osteosarcoma (OS) is a common cancerous bone tumor which has a detrimental impact on the lives of patients and their families. The present study aimed at investigating the underlying molecular mechanism of various drug treatments pertaining to OS, including dimethyl sulfoxide (DMSO), doxorubicin (DXP), Nutlin-3, actinomycin D (ActD) and etoposide (Eto). Microarray and p53 chromatin immunoprecipitation combined with sequencing (ChIP-seq) datasets of the OS cell line U2OS treated with distinct drugs were acquired from the Gene Expression Omnibus and differentially-expressed genes (DEGs) were screened for alignment analysis. The p53-binding target genes were identified and ChIP-seq and microarray gene expression data were combined to identify directly and indirectly targeted genes. A regulatory network of p53 was constructed with the acquired data. Finally, the Database for Annotation, Visualization and Integrated Discovery was interrogated for annotation of target genes. A total of 212 p53-binding peaks were obtained in the untreated group, whereas thousands of peaks were obtained in the treated groups. In total, ~1,000 target genes were identified in each of DXP, DMSO, Eto and ActD treatment groups, whereas the Nutlin-3 treatment group identified an increased number, with 5,458 target genes obtained. Several common DEGs including MDM2, TP53I3, RRM2B, FAS and SESN1 were targeted by all the drugs with the exception of DMSO. p53 regulated various genes including EHF, HOXA10 and BHLHE40 in the Nutlin-3 treatment group, whereas p53 regulated EHF, RFX3, TRAF40 and TCF7L2 in the DXR treatment group. The results of the present study indicate that p53 was able to directly regulate target genes including MDM2, TP53I3 and RRM2B or indirectly regulate numerous further genes through several hub genes including EHF and RFX through various drug treatments in U2OS cells. Furthermore, p53 regulated distinct molecular processes in various drug treatments.

Analysis of the molecular mechanism of osteosarcoma using a bioinformatics approach

The aim of this study was to explore the underlying molecular mechanism related to the process and progression of osteosarcoma (OS). The differentially expressed genes (DEGs) were downloaded from the Gene Expression Omnibus database. The pathway and gene ontology (GO) enrichment analysis, as well as transcription factor, tumor-associated gene and tumor suppressor gene analyses were performed to investigate the functions of DEGs. Next, the protein-protein interaction (PPI) network was constructed and module analysis was further assessed by cluster analysis with the overlapping neighborhood expansion (Cluster ONE) cytoscape plug-in. A total of 359 upregulated and 614 downregulated DEGs were identified to be differentially expressed between OS samples and normal controls. Pathways significantly enriched by DEGs included the focal adhesion and chromosome maintenance pathways. Significant GO terms were cell adhesion, cell cycle and nucleic acid metabolic processes. The upregulated PPI network was constructed with 170 nodes and the downregulated PPI network was constructed with 332 nodes. Breast-ovarian cancer gene 1 (BRCA1), melanocyte-stimulating hormone 2 (MSH2), cyclin D1 (CCND1) and integrin α5 (ITGA5) were identified to be hub proteins in PPI. In conclusion, the dysregulated genes played key roles in the progression of OS. Cell adhesion is a significant biological process in OS development, and the genes BRCA1, MSH2, CCND1 and ITGA5 may be potential targets in the therapy of OS.

The Functional Role of PMP22 Gene in the Proliferation and Invasion of Osteosarcoma

Background

As the most common primary bone tumor, osteosarcoma has an improved survival rates with advancement of treatment methods. A higher rate of metastasis, however, leads to the aggravation of the disease. Studies have shown that some genes, namely osteosarcoma metastasis-related genes, participate in the process of tumor metastasis. The peripheral myelin protein 22 (PMP22) gene has recently been found to be abundantly expressed in the oncogenesis of osteosarcoma. Its detailed role and function in the tumor metastasis, however, remains unknown.

Material/Methods

The recombinant retroviral plasmid pcDNA3.1-PMP22 was constructed and used to transfect osteosarcoma cells SOSP-M, whose cell proliferation was measured by MTT method. The formation of tumor cell colony, the cell migration and invasion were also measured. The signal transduction pathway MAPK was further analyzed by Western blotting.

Results

The pcDNA3.1-PMP22 plasmid was confirmed to have a 305bp PMP22 fragment by EcoRI-XhoI dual digestion. Compared to the control group, osteosarcoma cell invasion was significantly facilitated by the transfection of pcDNA3.1-PMP22 plasmid (p<0.05). The recombinant plasmid also significantly potentiated the formation of tumor cell colony and increased the migration and invasion ability of tumor cells (p<0.05 in all cases). Phosphorylated p-ERK and p-P38 were also up-regulated by vector transfection (p<0.05).

Conclusions

Osteosarcoma metastasis-related gene PMP22 participates in the proliferation, invasion, migration and colony formation of osteosarcoma cells possibly via the MAPK signal transduction pathway, providing evidences for further investigation of metastatic mechanism of osteosarcoma.