CBX7 Expression in Oncocytic Thyroid Neoplastic Lesions (Hürthle Cell Adenomas and Carcinomas)

Decoding the interaction between miR-19a and CBX7 focusing on the implications for tumor suppression in cancer therapy

Cancer is a complex and multifaceted disease characterized by uncontrolled cell growth, genetic alterations, and disruption of normal cellular processes, leading to the formation of malignant tumors with potentially devastating consequences for patients. Molecular research is important in the diagnosis and treatment, one of the molecular mechanisms involved in various cancers is the fluctuation of gene expression. Non-coding RNAs, especially microRNAs, are involved in different stages of cancer. MicroRNAs are small RNA molecules that are naturally produced within cells and bind to the 3'-UTR of target mRNA, repressing gene expression by regulating translation. Overexpression of miR-19a has been reported in human malignancies. Upregulation of miR-19a as a member of the miR-17-92 cluster is key to tumor formation, cell proliferation, survival, invasion, metastasis, and drug resistance. Furthermore. bioinformatics and in vitro data reveal that the miR-19a-3p isoform binds to the 3'UTR of CBX7 and was identified as the miR-19a-3p target gene. CBX7 is known as a tumor suppressor. This review initially describes the regulation of mir-19a in multiple cancers. Accordingly, the roles of miR-19 in affecting its target gene expression CBX7 in carcinoma also be discussed.

CBX7 is Dualistic in Cancer Progression Based on its Function and Molecular Interactions

Chromobox protein homolog 7 (CBX7) is a member of the Chromobox protein family and participates in the formation of the polycomb repressive complex 1(PRC1). In cells, CBX7 often acts as an epigenetic regulator to regulate gene expression. However, pathologically, abnormal expression of CBX7 can lead to an imbalance of gene expression, which is closely related to the occurrence and progression of cancers. In cancers, CBX7 plays a dual role; On the one hand, it contributes to cancer progression in some cancers by inhibiting oncosuppressor genes. On the other hand, it suppresses cancer progression by interacting with different molecules to regulate the synthesis of cell cycle-related proteins. In addition, CBX7 protein may interact with different RNAs (microRNAs, long noncoding RNAs, circular RNAs) in different cancer environments to participate in a variety of pathways, affecting the development of cancers. Furthermore, CBX7 is involved in cancer-related immune response and DNA repair. In conclusion, CBX7 expression is a key factor in the occurrence and progression of cancers.

Approach the Invasive Potential with Hurthle Cell Tumors of Thyroid

To observe the expression of P53, CyclinD1, Ki-67, Galectin-3, COX-2, Bcl-2 and approach their contribution on assessing the invasive potential for Hurthle cell tumors. Seventy-three cases of Hurthle cell tumor were collected for immunohistochemistry staining. The patients were followed up with 8 months to 5 years. Tumors were divided into four grades according to invasion and diameter:(1) extremely low risk (27 cases that less than 2 cm and without invasion), (2) low risk (18 cases that within 2-3.9 cm and without invasion), (3) moderate risk (21 cases that achieve 4 cm and without invasion), (4) high risk (7 cases that with invasion of capsule/vessel in spite of the diameter). Immunostaining presented that all 73 cases were positive with Galectin-3, COX-2 and Bcl-2. For each group, P53 positive were 29.6%, 55.6%, 90.5%, 100.0%; CyclinD1 stained with 7.4%,22.2%,52.4%,100.0% and Ki-67 were 0.0%,5.6%,9.5%,28.6%, respectively. The higher risk of tumor, the more cases that positive expressed P53 and CyclinD1. After following up within 49 patients, two of the recurring cases were positive with P53 and CyclinD1 and one of which was also highly expressed Ki-67. Detecting P53, CyclinD1 and Ki-67 might provide reference for invasive potential assessment with Hurthle cell tumors but not Galectin-3, COX-2 and Bcl-2.

Preoperative Diagnosis of Neoplastic or Malignant Hürthle Cell Lesions: A Chimera?

OBJECTIVE

We aimed to review all cytological specimens with Hürthle cells (HC) diagnosed in our institution, identify cytological features related to neoplastic (adenoma or carcinoma) and malignant histology, and discuss the role of clinicopathological findings and clinical management in these cases.

STUDY DESIGN

We included 359 thyroid fine-needle aspiration cytology cases in our study. We reviewed the clinical and cytological features of surgical cases and correlated them with histological diagnosis. We also reviewed the literature on this issue.

RESULTS

We found a significant association between neoplasia and highly cellular smears, the absence of colloid, the presence of microfollicles, large-cell dysplasia, prominent nucleoli or macronucleoli, coarse chromatin, nuclear grooves and inclusions, nuclear irregularity, and pleomorphism. The absence of colloid, high cellularity, > 25% of isolated HC, the presence of tridimensional groups, transgressing vessels, nuclear irregularity, prominent nucleoli or macronucleoli, coarse chromatin, hyperchromatism, pleomorphism, and diffuse large-cell dysplasia were features significantly associated with malignancy.

CONCLUSIONS

No cytological feature alone can predict histological outcome, but all findings related to a neoplastic or malignant histology must be assessed. Individualized management protocols should be developed in each institution.

Hürthle Cell Carcinoma in a Lingual Thyroid

OBJECTIVE

To present a case of lingual thyroid Hürthle cell carcinoma (HCC).

CLINICAL PRESENTATION AND INTERVENTION

A 37-year-old female presented with dysphagia and recurrent haemorrhage. Histopathology was suggestive of HCC; the tumour was excised by the trans-glossal approach which provided adequate exposure and helped avert external scarring or mandibular osteotomy. Histopathology showed a tumour-positive right lateral resection margin. This prompted referral to nuclear medicine for radio-iodine ablation.

CONCLUSION

Lingual thyroid cases should be followed up closely and fine-needle aspiration biopsy should be considered when in doubt.

Polycomb protein family member CBX7 plays a critical role in cancer progression

CBX7 is a polycomb protein that participates in the formation of polycomb repressive complex 1. Apart from few exceptions, CBX7 expression is lost in human malignant neoplasias and a clear correlation between its downregulated expression and a cancer aggressiveness and poor prognosis has been observed. These findings indicate a critical role of CBX7 in cancer progression. Consistently, CBX7 is able to differentially regulate crucial genes involved in cancer progression and in epithelial-mesenchymal transition, as osteopontin and E-cadherin. Recent evidences indicate a role of CBX7 also in the modulation of response to therapy. In conclusion, CBX7 represents an important prognostic factor, whose loss of expression in general indicates a bad prognosis and a progression towards a fully malignant phenotype.