ZO-1 expression shows prognostic value in chronic B cell leukemia

Carbenoxolone upregulates TRAIL\TRAILR2 expression and enhances the anti-neoplastic effect of doxorubicin in experimentally induced hepatocellular carcinoma in rats

AIMS

This study investigates the in vivo anticancer activity of carbenoxolone (CBX) and its role in fighting hepatocellular carcinoma (HCC) progression and alleviating resistance against doxorubicin (DOX). Moreover, the molecular mechanism of action of CBX is explored.

METHODS

HCC was induced in Sprague Dawley rats via biweekly administration of thioacetamide (TAA) (200 mg/kg) intraperitoneally (i.p.) for 16 weeks after administering a single dose of diethylnitrosamine (DEN) (200 mg/kg, i.p.). A prophylactic model was established by treating rats with i.p. CBX (20 mg/kg/day) for 4 weeks starting on week 13 post-TAA injection. A therapeutic model was established by treating rats with CBX, DOX, or their combination for 7 weeks following 16 weeks of TAA administration. Serum Alpha-fetoprotein (AFP) and biochemical markers of hepatic functions were assessed. Histopathological examinations of hepatic tissues were performed. Immunohistochemical and qRT-PCR analyses were applied to assess the differential expressions of TRAIL/TRAILR2, Bcl-2, TGF-β1, and caspases 3, 8, and 9.

RESULTS

CBX markedly improved hepatic functions, reduced serum AFP levels, and alleviated TAA-induced hepatic histopathological alterations. CBX triggered apoptosis as evident by upregulating apoptotic markers: TRAIL/TRAILR2, caspases 3, 8, and 9, and downregulating the antiapoptotic protein Bcl-2. CBX downregulated TGF-β1. Interestingly, CBX/DOX combination mitigated hepatic damage and induced apoptosis in a way that surpassed DOX-only treatment.

CONCLUSION

The current study proposes that CBX is a promising anti-tumor compound, which can work effectively under prophylactic and therapeutic modes. Interestingly, CBX enhanced the anti-tumor effect of DOX. CBX exerted these effects via, in part, stimulating TRAIL-induced apoptosis along with attenuating fibrosis.

Comprehensive Pan-Cancer Analysis of Connexin 43 as a Potential Biomarker and Therapeutic Target in Human Kidney Renal Clear Cell Carcinoma (KIRC)

Background and Objectives: Connexin 43 (Cx43) is involved in the transfer of small signaling molecules between neighboring cells, thereby exerting a major influence on the initiation and progression of tumorigenesis. However, there is a lack of systematic research on Cx43 expression and its predictive role in clinical diagnosis and prognosis in pan-cancer. Materials and Methods: Several biological databases were used to evaluate the expression levels of GJA1 (encoding Cx43) and its diagnostic and prognostic significance in pan-cancer. We targeted kidney renal clear cell carcinoma (KIRC) and investigated the relationship between GJA1 expression and different clinical features of KIRC patients. Then, we performed cell-based experiments to partially confirm our results and predicted several proteins that were functionally related to Cx43. Results: The expression of GJA1 has a high level of accuracy in predicting KIRC. High GJA1 expression was remarkably correlated with a favorable prognosis, and this expression was reduced in groups with poor clinical features in KIRC. Cell experiments confirmed the inhibitory effects of increased GJA1 expression on the migratory capacity of human renal cancer (RCC) cell lines, and protein-protein interaction (PPI) analysis predicted that CDH1 and CTNNB1 were closely related to Cx43. Conclusions: GJA1 could be a promising independent favorable prognostic factor for KIRC, and upregulation of GJA1 expression could inhibit the migratory capacity of renal cancer cells.

Connexin 43 (Cx43) in cancer: Implications for therapeutic approaches via gap junctions

Gap junctions are membrane channels found in all cells of the human body that are essential to cellular physiology. Gap junctions are formed from connexin proteins and are responsible for transfer of biologically active molecules, metabolites, and salts between neighboring cells or cells and their extracellular environment. Over the last few years, aberrant connexin 43 (Cx43) expression has been associated with cancer recurrence, metastatic spread, and poor survival. Here we provide an overview of the general structure and function of gap junctions and review their roles in different cancer types. We discuss new therapeutic approaches targeting Cx43 and potential new ways of exploiting gap junction transfer for drug delivery and anti-cancer treatment. The permeability of Cx43 channels to small molecules and macromolecules makes them highly attractive targets for delivering drugs directly into the cytoplasm. Cancer cells overexpressing Cx43 may be more permeable and sensitive to chemotherapeutics. Because Cx43 can either act as a tumor suppressor or oncogene, biomarker analysis and a better understanding of how Cx43 contextually mediates cancer phenotypes will be required to develop clinically viable Cx43-based therapies.

"Stealth dissemination" of macrophage-tumor cell fusions cultured from blood of patients with pancreatic ductal adenocarcinoma

Here we describe isolation and characterization of macrophage-tumor cell fusions (MTFs) from the blood of pancreatic ductal adenocarcinoma (PDAC) patients. The MTFs were generally aneuploidy, and immunophenotypic characterizations showed that the MTFs express markers characteristic of PDAC and stem cells, as well as M2-polarized macrophages. Single cell RNASeq analyses showed that the MTFs express many transcripts implicated in cancer progression, LINE1 retrotransposons, and very high levels of several long non-coding transcripts involved in metastasis (such as MALAT1). When cultured MTFs were transplanted orthotopically into mouse pancreas, they grew as obvious well-differentiated islands of cells, but they also disseminated widely throughout multiple tissues in "stealth" fashion. They were found distributed throughout multiple organs at 4, 8, or 12 weeks after transplantation (including liver, spleen, lung), occurring as single cells or small groups of cells, without formation of obvious tumors or any apparent progression over the 4 to 12 week period. We suggest that MTFs form continually during PDAC development, and that they disseminate early in cancer progression, forming "niches" at distant sites for subsequent colonization by metastasis-initiating cells.