Carbonic anhydrase IX: a promising diagnostic and prognostic biomarker in breast carcinoma

Immunohistochemical evaluation of Glut1 in dentigerous cysts, odontogenic keratocysts, and ameloblastoma

Context

Glucose uptake may be considered the rate-limiting step for the growth and metabolism of the cancer cell. Studies on GLUT1 have shown that GLUT1 is involved in cell survival and proliferation in both healthy and pathological circumstances. GLUT1 expression is regarded as one of the crucial elements in the development of local aggressiveness, tumour invasiveness, and metastasis, particularly in malignant tumours. The role of glut1 in odontogenic cysts and tumours has remained uncertain.

Aim

The aim of the study is to assess the expression of Glut1 in dentigerous cysts, odontogenic keratocysts, and ameloblastoma.

Settings and Design

The study was conducted in GSL Dental College. The study design was a resprospective immunohistochemical study.

Methods and Material

Formalin-fixed, paraffin-embedded blocks of histologically confirmed cases (n = 50), 10 cases of odontogenic keratocysts, dentigerous cysts, ameloblastomas solid, ameloblastomas unicystic, and dental follicles each. Brown colour staining was considered as positive staining for GLUT1. Quantitative analysis was performed by counting the number of labelled cells, and semi-quantitative analysis was conducted by assigning immunostaining intensity scores.

Statistical Analysis

Chi-square test was used to compare differences between the groups. A P value of ≤0.05 was considered as statistically significant.

Results

Odontogenic keratocysts and unicystic ameloblastoma showed ≥50% of label cells with strong intensity of staining. Odontogenic keratocysts and solid ameloblastoma showed sub-cellular localisation of staining in the cytoplasm and membrane. Dentigerous cysts exhibited combined nucleus, cytoplasm, and membrane sub-cellular localisation of staining.

Conclusions

The development of ameloblastomas, odontogenic keratocysts, and dentigerous cysts appears to be influenced by GLUT-1. Variation in its expression may aid in explanation of some of the differences in biological activity of these lesions.

Differential CMS-Related Expression of Cell Surface Carbonic Anhydrases IX and XII in Colorectal Cancer Models-Implications for Therapy

Tumor-associated carbonic anhydrases IX (CAIX) and XII (CAXII) have long been in the spotlight as potential new targets for anti-cancer therapy. Recently, CAIX/CAXII specific inhibitor SLC-0111 has passed clinical phase I study and showed differential response among patients with colorectal cancer (CRC). CRC can be classified into four different consensus molecular subgroups (CMS) showing unique expression patterns and molecular traits. We questioned whether there is a CMS-related CAIX/CAXII expression pattern in CRC predicting response. As such, we analyzed transcriptomic data of tumor samples for CA9/CA12 expression using Cancertool. Protein expression pattern was examined in preclinical models comprising cell lines, spheroids and xenograft tumors representing the CMS groups. Impact of CAIX/CAXII knockdown and SLC-0111 treatment was investigated in 2D and 3D cell culture. The transcriptomic data revealed a characteristic CMS-related CA9/CA12 expression pattern with pronounced co-expression of both CAs as a typical feature of CMS3 tumors. Protein expression in spheroid- and xenograft tumor tissue clearly differed, ranging from close to none (CMS1) to strong CAIX/CAXII co-expression in CMS3 models (HT29, LS174T). Accordingly, response to SLC-0111 analyzed in the spheroid model ranged from no (CMS1) to clear (CMS3), with moderate in CMS2 and mixed in CMS4. Furthermore, SLC-0111 positively affected impact of single and combined chemotherapeutic treatment of CMS3 spheroids. In addition, combined CAIX/CAXII knockdown and more effective treatment with SLC-0111 reduced clonogenic survival of CMS3 modelling single cells. In conclusion, the preclinical data support the clinical approach of targeted CAIX/CAXII inhibition by showing linkage of expression with response and suggest that patients with CMS3-classified tumors would most benefit from such treatment.

Emergence of the Dedifferentiated Phenotype in Hepatocyte-Derived Tumors in Mice: Roles of Oncogene-Induced Epigenetic Alterations

Hepatocellular carcinoma often reactivates the genes that are transiently expressed in fetal or neonatal livers. However, the mechanism of their activation has not been elucidated. To explore how oncogenic signaling pathways could be involved in the process, we examined the expression of fetal/neonatal genes in liver tumors induced by the introduction of myristoylated v-akt murine thymoma viral oncogene (AKT), HRas proto-oncogene, guanosine triphosphatase (HRASV12), and MYC proto-oncogene, bHLH transcription factor (Myc), in various combinations, into mouse hepatocytes in vivo. Distinct sets of fetal/neonatal genes were activated in HRAS- and HRAS/Myc-induced tumors: aldo-keto reductase family 1, member C18 (Akr1c18), glypican 3 (Gpc3), carboxypeptidase E (Cpe), adenosine triphosphate-binding cassette, subfamily D, member 2 (Abcd2), and trefoil factor 3 (Tff3) in the former; insulin-like growth factor 2 messenger RNA binding protein 3 (Igf2bp3), alpha fetoprotein (Afp), Igf2, and H19, imprinted maternally expressed transcript (H19) in the latter. Interestingly, HRAS/Myc-induced tumors comprised small cells with a high nuclear/cytoplasmic ratio and messenger RNA (mRNA) expression of delta-like noncanonical Notch ligand 1 (Dlk1), Nanog homeobox (Nanog), and sex determining region Y-box 2 (Sox2). Both HRAS- and HRAS/Myc-induced tumors showed decreased DNA methylation levels of Line1 and Igf2 differentially methylated region 1 and increased nuclear accumulation of 5-hydroxymethylcytosine, suggesting a state of global DNA hypomethylation. HRAS/Myc-induced tumors were characterized by an increase in the mRNA expression of enzymes involved in DNA methylation (DNA methyltransferase [Dnmt1, Dnmt3]) and demethylation (ten-eleven-translocation methylcytosine dioxygenase 1 [Tet1]), sharing similarities with the fetal liver. Although mouse hepatocytes could be transformed by the introduction of HRAS/Myc in vitro, they did not express fetal/neonatal genes and sustained global DNA methylation, suggesting that the epigenetic alterations were influenced by the in vivo microenvironment. Immunohistochemical analyses demonstrated that human hepatocellular carcinoma cases with nuclear MYC expression were more frequently positive for AFP, IGF2, and DLK1 compared with MYC-negative tumors. Conclusion: The HRAS signaling pathway and its interactions with the Myc pathway appear to reactivate fetal/neonatal gene expression in hepatocytic tumors partly through epigenetic alterations, which are dependent on the tumor microenvironment.