Enhanced Chemoprevention of Prostate Cancer by Combining Arctigenin with Green Tea and Quercetin in Prostate-Specific Phosphatase and Tensin Homolog Knockout Mice.

The low bioavailability of most phytochemicals limits their anticancer effects in humans. The present study was designed to test whether combining arctigenin (Arc), a lignan mainly from the seed of Arctium lappa, with green tea (GT) and quercetin (Q) enhances the chemopreventive effect on prostate cancer. We performed in vitro proliferation studies on different cell lines. We observed a strong synergistic anti-proliferative effect of GT+Q+Arc in exposing androgen-sensitive human prostate cancer LNCaP cells. The pre-malignant WPE1-NA22 cell line was more sensitive to this combination. No cytotoxicity was observed in normal prostate epithelial PrEC cells. For an in vivo study, 3-week-old, prostate-specific PTEN (phosphatase and tensin homolog) knockout mice were treated with GT+Q, Arc, GT+Q+Arc, or the control daily until 16 weeks of age. In vivo imaging using prostate-specific membrane antigen (PSMA) probes demonstrated that the prostate tumorigenesis was significantly inhibited by 40% (GT+Q), 60% (Arc at 30 mg/kg bw), and 90% (GT+Q+Arc) compared to the control. A pathological examination showed that all control mice developed invasive prostate adenocarcinoma. In contrast, the primary lesion in the GT+Q and Arc alone groups was high-grade prostatic intraepithelial neoplasia (PIN), with low-grade PIN in the GT+Q+Arc group. The combined effect of GT+Q+Arc was associated with an increased inhibition of the androgen receptor, the PI3K/Akt pathway, Ki67 expression, and angiogenesis. This study demonstrates that combining Arc with GT and Q was highly effective in prostate cancer chemoprevention. These results warrant clinical trials to confirm the efficacy of this combination in humans.

BAT26 Only Microsatellite Instability with High Tumor Mutation Burden-A Rare Entity Associated with PTEN Protein Loss and High PD-L1 Expression.

Detecting microsatellite instability (MSI) in advanced cancers is crucial for clinical decision-making, as it helps in identifying patients with differential treatment responses and prognoses. BAT26 is a highly sensitive MSI marker that defines the mismatch repair (MMR) status with high sensitivity and specificity. However, isolated BAT26-only instability is rare and has not been previously reported. Of the 6476 cases tested using pentaplex MSI polymerase chain reaction, we identified two BAT26-only instability cases (0.03%) in this study. The case #1 patient was diagnosed with endometrial adenocarcinoma without MMR germline mutations. The endometrial tumor showed BAT26-only instability, partial loss of MLH1/PMS2 protein expression, and a high programmed cell death ligand 1 (PD-L1) combined positive score (CPS = 8). The tumor exhibited a somatic phosphatase and tensin homolog (PTEN) R303P missense mutation and loss of the PTEN protein. On a comprehensive cancer panel sequencing with ≥500 genes, the tumor showed an MSI score of 11.38% and high tumor mutation burden (TMB) (19.5 mt/mb). The case #2 patient was diagnosed with colorectal carcinoma with proficient MMR and PTEN protein loss without PTEN alteration, as well as a high PD-L1 CPS (CPS = 10). A pathogenic KRAS A146T mutation was detected with an MSI score of 3.36% and high TMB (13 mt/mb). In conclusion, BAT26-only instability is very rare and associated with PTEN protein loss, high TMB, and a high PD-L1 score. Our results suggest that patients with BAT26-only instability may show good responses to immunotherapy.

Cell Cycle Progression Score, but Not Phosphatase and Tensin Homolog Loss, Is an Independent Prognostic Factor for Metastasis in Intermediate- and High-risk Prostate Cancer in Men Treated With and Without Salvage Radiotherapy.

PURPOSE: The prognostic value for metastasis of the cell-cycle progression score and phosphatase and tensin homolog haven't been evaluated jointly in contemporary men with exclusively intermediate- or high-risk prostate cancer. We evaluated associations of cell-cycle progression and phosphatase and tensin homolog with metastasis-free survival in contemporary intermediate/high-risk prostate cancer patients overall, and intermediate/high-risk men receiving salvage radiotherapy. MATERIALS AND METHODS: In a case-cohort of 209 prostatectomy patients with intermediate/high-risk prostate cancer, and a cohort of 172 such men who received salvage radiotherapy, cell-cycle progression score was calculated from RNA expression, and phosphatase and tensin homolog was analyzed by immunohistochemistry. Proportional hazards regression, weighted for case-cohort design or unweighted for the salvage radiotherapy cohort, was used to evaluate associations of cell-cycle progression, phosphatase and tensin homolog with metastasis-free survival. Improvement in model discrimination was evaluated with the concordance index. RESULTS: In the case-cohort 41 men had metastasis, and 17 developed metastasis in the salvage radiotherapy cohort, at median follow-up of 3 and 4 years, respectively. For both case-cohort and salvage radiotherapy cohort, cell-cycle progression was independently associated with metastasis-free survival after adjustment for Cancer of the Prostate Risk Assessment Post-Surgical: hazard ratio (95% confidence interval) = 3.11 (1.70-5.69) and 1.85 (1.19-2.85), respectively. Adding cell-cycle progression to Cancer of the Prostate Risk Assessment Post-Surgical increased the concordance index from 0.861 to 0.899 (case-cohort), and 0.745 to 0.819 (salvage radiotherapy cohort). Although statistically significant in univariate analyses, phosphatase and tensin homolog was no longer significant after adjustment for Cancer of the Prostate Risk Assessment Post-Surgical. Analysis of interaction with National Comprehensive Cancer Network risk group showed that cell-cycle progression had the strongest effect among unfavorable intermediate-risk men. CONCLUSIONS: In the first study to evaluate metastasis risk associated with cell-cycle progression and phosphatase and tensin homolog in exclusively intermediate/high-risk prostate cancer, and in such men with salvage radiotherapy, cell-cycle progression but not phosphatase and tensin homolog was associated with significantly increased 2- to 3-fold risk of metastasis after Cancer of the Prostate Risk Assessment Post-Surgical adjustment.

Fuzheng Kang' ai decoction inhibits cell proliferation, migration and invasion by modulating mir-21-5p/human phosphatase and tensin homology deleted on chromosome ten in lung cancer cells.

OBJECTIVE: To elucidate the potential molecular mechanism by which Fuzheng Kang'ai decoction (, FZKA) inhibits proliferation, migration, and invasion of lung cancer cells. METHODS: Varying FZKA concentrations were used to manage lung cancer cells (A549 and PC9). We employed: cell counting kit-8 (CCK-8) and plate clone for-mation assays to examine the cell viability; flow cytometry (FCM) to analyze the cycle arrest; transwell and wound-healing assays to assess the cell invasion and migration, respectively. Further, a quantitative real-time polymerase chain reaction (qRT-PCR) assay was adopted to evaluate the miR-21-5p expression. For protein expression analysis, we employed the Western blot technique. Recombinant miR-21-5p overexpression adenovirus vector harboring GFP was constructed and transfected into A549 and PC9, after which we explored the effect of FZKA on miR-21-5p overexpression. RESULTS: Notably, treatment with FZKA inhibited viability, clone-formation ability, invasion, and migration of lung cancer cells. Mechanistically, FZKA markedly suppressed miR-21-5p expression but elevated the human phosphatase and tensin homology deleted on chromosome ten (PTEN) protein level in both A549 and PC9 cells. Over-expression of miR-21-5p lowered PTEN protein expression. Besides, overexpressed miR-21-5p levels with adenovirus antagonized FZKA-upregulated PTEN protein expression. CONCLUSION: The present study demonstrates how FZKA modulates cell biological behaviors, for instance, it impedes the proliferation by upregulating PTEN expression with miR-21-5p as the target. These findings unveil the potential novel molecular mechanisms from the microRNA aspect by which FZKA suppresses the growth of human lung cancer cells.

Therapeutic efficacy of FASN inhibition in preclinical models of HCC.

BACKGROUND AND AIMS: Aberrant activation of fatty acid synthase (FASN) is a major metabolic event during the development of HCC. We evaluated the therapeutic efficacy of TVB3664, a FASN inhibitor, either alone or in combination, for HCC treatment. APPROACH AND RESULTS: The therapeutic efficacy and the molecular pathways targeted by TVB3664, either alone or with tyrosine kinase inhibitors or the checkpoint inhibitor anti-programmed death ligand 1 antibody, were assessed in human HCC cell lines and multiple oncogene-driven HCC mouse models. RNA sequencing was performed to elucidate the effects of TVB3664 on global gene expression and tumor metabolism. TVB3664 significantly ameliorated the fatty liver phenotype in the aged mice and AKT-induced hepatic steatosis. TVB3664 monotherapy showed moderate efficacy in NASH-related murine HCCs, induced by loss of phosphatase and tensin homolog and MET proto-oncogene, receptor tyrosine kinase (c-MET) overexpression. TVB3664, in combination with cabozantinib, triggered tumor regression in this murine model but did not improve the responsiveness to immunotherapy. Global gene expression revealed that TVB3664 predominantly modulated metabolic processes, whereas TVB3664 synergized with cabozantinib to down-regulate multiple cancer-related pathways, especially the AKT/mammalian target of rapamycin pathway and cell proliferation genes. TVB3664 also improved the therapeutic efficacy of sorafenib and cabozantinib in the FASN-dependent c-MYC-driven HCC model. However, TVB3664 had no efficacy nor synergistic effects in FASN-independent murine HCC models. CONCLUSIONS: This preclinical study suggests the limited efficacy of targeting FASN as monotherapy for HCC treatment. However, FASN inhibitors could be combined with other drugs for improved effectiveness. These combination therapies could be developed based on the driver oncogenes, supporting precision medicine approaches for HCC treatment.

Novel candidate factors predicting the effect of S-1 adjuvant chemotherapy of pancreatic cancer.

The collagen gel droplet-embedded drug sensitivity test (CD-DST) was revealed to be useful for predicting the effect of S-1 adjuvant chemotherapy for pancreatic ductal adenocarcinoma (PDAC). However, collection of an adequate number of PDAC cells is difficult due to the surrounding fibroblasts. Thus, the aim of this study was to discover novel biomarkers to predict chemosensitivity based on the CD-DST results. Proteomics analysis was performed using liquid chromatography tandem mass spectrometry (LC-MS/MS). Candidate proteins were validated in patients with 5-FU CD-DST results via immunohistochemistry (IHC). The relationships between the candidate proteins and the effect of the adjuvant S-1 were investigated via IHC. Among the 2696 proteins extracted by LC-MS/MS, C1TC and SAHH could accurately predict the CD-DST results. Recurrence-free survival (RFS) was significantly improved in the IHC-positive group compared with the IHC-negative group in both factors. The negative group did not show a significant difference from the group that did not receive S-1. The double-positive group was associated with significantly prolonged RFS compared to the no adjuvant chemotherapy group. C1TC and SAHH have been shown to be useful biomarkers for predicting 5-FU sensitivity as a substitute for the CD-DST in adjuvant chemotherapy for PDAC.

Jianpijiedu fang improves survival of hepatocarcinoma mice by affecting phosphatase and tensin homolog, phosphoinositide 3-kinase, and focal adhesion kinase.

OBJECTIVE: To investigate the effect of Jianpijiedu Fang (JPJDF) on phosphatase and tensin homolog (PTEN), phosphoinositide 3-kinase (PI3K), and focal adhesion kinase (FAK), and on the survival of hepatocellular carcinoma (HCC) nude mice. METHODS: Forty male nude mice were randomly divided into 4 groups. Human HCC tissue was implanted in the livers of three groups. After 24 h, the three groups were treated respectively with JPJDF (37.5 g/kg), saline (20 mL/kg) and Tegafur (FT-207, 160 mg/kg) once a day for 10 weeks. The control group without implanting the tissue was concurrently treated with saline (20 mL/kg). The survival data and body weight of all mice were recorded, and expression levels of PTEN, PI3K and FAK in normal tissue and cancer tissue of the livers were evaluated with immunohistochemical method. RESULTS: The cumulative survival rate of the mice in the JPJDF group was higher than those of the other groups. The rate of weight loss was the lowest in JPJDF group. The survivability and weight loss rate in FT-207 group were the poorest in all groups. The expression intensity of PTEN was higher in normal tissues than in cancer tissues, and lower in the normal tissues of HCC models than in that of mice without HCC. The PTEN expression intensity in normal tissue and cancer tissue from mice treated with FT-207 were lower than that from the mice treated with JPJDF or saline. The expression intensity of PI3K was higher in cancer tissue than in normal tissue. The PI3K expression intensity was the lowest in normal tissue and cancer tissue from mice treated with JPJDF, and the intensity from mice treated with FT-207 was the highest. In mice treated with JPJDF, the expression intensity of FAK was higher in the normal tissue and lower in the cancer tissue than those of the other treatment groups. CONCLUSION: The mechanism accounting for the prolonged survival of HCC-bearing mice treated with JPJDF might be related to the reduction in weight loss and the benign regulation of PTEN, PI3K, and FAK.

Epidermal growth factor modulates tyrosine phosphorylation of a novel tensin family member, tensin3.

Here, we report the identification of a new tensin family member, tensin3, and its role in epidermal growth factor (EGF) signaling pathway. Human tensin3 cDNA encodes a 1445 amino acid sequence that shares extensive homology with tensin1, tensin2, and COOH-terminal tensin-like protein. Tensin3 is expressed in various tissues and in different cell types such as endothelia, epithelia, and fibroblasts. The potential role of tensin3 in EGF-induced signaling pathway is explored. EGF induces tyrosine phosphorylation of tensin3 in MDA-MB-468 cells in a time- and dose-dependent manner, but it is independent of an intact actin cytoskeleton or phosphatidylinositol 3-kinase. Activation of EGF receptor is necessary but not sufficient for tyrosine phosphorylation of tensin3. It also requires Src family kinase activities. Furthermore, tensin3 forms a complex with focal adhesion kinase and p130Cas in MDA-MB-468 cells. Addition of EGF to the cells induces dephosphorylation of these two molecules, leads to disassociation of the tensin3-focal adhesion kinase-p130Cas complex, and enhances the interaction between tensin3 and EGF receptor. Our results demonstrate that tensin3 may function as a platform for the disassembly of EGF-related signaling complexes at focal adhesions.

Cilostazol prevents focal cerebral ischemic injury by enhancing casein kinase 2 phosphorylation and suppression of phosphatase and tensin homolog deleted from chromosome 10 phosphorylation in rats.

This study shows the in vivo neuroprotective effect of cilostazol against cerebral ischemic injury evoked by subjecting rats to 2-h occlusion of middle cerebral artery (MCAO) followed by 24-h reperfusion. We observed the signaling pathway by which cilostazol suppressed MCAO-induced increased phosphorylation of phosphatase and tensin homolog deleted from chromosome 10 (PTEN) and apoptosis via increased phosphorylation of casein kinase 2 (CK2). When rats received 30 mg/kg cilostazol orally two times at 5 min and 4 h after the completion of ischemia, the infarct area was significantly reduced in the cortex and striatum with improvement of neurological deterioration. Increased DNA fragmentation in the penumbral zone was significantly reduced by cilostazol. Cilostazol significantly elevated phosphorylation levels of CK2, Akt, and cyclic AMP response element-binding protein (CREB) in association with increased Bcl-2 in the ischemic area, whereas the elevated PTEN phosphorylation was significantly reduced, all of which were antagonized by iberiotoxin, a maxi-K channel blocker, administered intracisternally 30 min before ischemia. In conclusion, cilostazol ameliorates the neuronal damage by suppression of apoptotic cell death via the maxi-K channel opening-coupled up-regulation of CK2 phosphorylation and down-regulation of PTEN phosphorylation with resultant increase in the Akt and CREB phosphorylation and increased Bcl-2 protein.

Caspase-dependent cleavage of tensin induces disruption of actin cytoskeleton during apoptosis.

Members of both calpain and caspase protease families can degrade several components of focal adhesions, leading to disassembly of these complexes. In this report, we investigated the disappearance of tensin from cell adhesion sites of chicken embryonic fibroblast cells (CEFs) exposed to etoposide and demonstrated that loss of tensin from cell adhesions during etoposide-induced apoptosis may be due to degradation of tensin by caspase-3. Tensin cleavage by caspase-3 at the sequence DYPD(1226)G separates the amino-terminal region containing the actin binding domain and the carboxyl-terminal region containing the SH2 domain. The resultant carboxyl-terminal fragment of tensin is unable to bind phosphoinositide 3-kinase (PI3-kinase) transducing cell survival signaling. We also demonstrated that overexpression of the amino-terminal tensin fragment induced disruption of actin cytoskeleton in chicken embryonic fibroblasts. Therefore, caspase-mediated cleavage of tensin contributes to the disruption of actin organization and interrupts ECM-mediated survival signals through phosphatidylinositol 3-kinase.

Molecular characterization of human tensin.

Tensin is a focal-adhesion molecule that binds to actin filaments and interacts with phosphotyrosine-containing proteins. To analyse tensin's function in mammals, we have cloned tensin cDNAs from human and cow. The isolated approx. 7.7-kb human cDNA contains an open reading frame encoding 1735 amino acid residues. The amino acid sequence of human tensin shares 60% identity with chicken tensin, and contains all the structural features described previously in chicken tensin. This includes the actin-binding domains, the Src homology domain 2, and the region similar to a tumour suppressor, PTEN. Two major differences between human and chicken tensin are (i) the lack of the first 54 residues present in chicken tensin, and (ii) the addition of 34- and 38-residue inserts in human and bovine tensin. In addition, our interspecies sequencing data have uncovered the presence of a glutamine/CAG repeat that appears to have expanded in the course of evolution. Northern-blot analysis reveals a 10-kb message in most of the human tissues examined. An additional 9-kb message is detected in heart and skeletal muscles. The molecular mass predicted from the human cDNA is 185 kDa, although both endogenous and recombinant human tensin migrate as 220-kDa proteins on SDS/PAGE. The discrepancy is due to the unusually low electrophoretic mobility of the central region of the tensin polypeptide (residues 306-981). A survey of human prostate and breast cancer cell lines by Western-blot analysis shows a lack of tensin expression in most cancer cell lines, whereas these lines express considerable amounts of focal-adhesion molecules such as talin and focal-adhesion kinase. Finally, tensin is rapidly cleaved by a focal-adhesion protease, calpain II. Incubation of cells with a calpain inhibitor, MDL, prevented tensin cleavage and induced morphological change in these cells, suggesting that cleavage of tensin and other focal-adhesion constituents by calpain disrupts maintenance of normal cell shape.

A testis-specific gene, TPTE, encodes a putative transmembrane tyrosine phosphatase and maps to the pericentromeric region of human chromosomes 21 and 13, and to chromosomes 15, 22, and Y.

To contribute to the creation of a transcription map of human chromosome 21 (HC21) and to the identification of genes that may be involved in the pathogenesis of Down syndrome, exon trapping was performed from HC21-specific cosmids covering the entire chromosome. More than 700 exons have been identified to date. One such exon, hmc01a06, maps to YAC 831B6 which contains marker D21Z1 (alphoid repeats) and had previously been localized to the pericentromeric region of HC21. Northern-blot analysis revealed a 2.5-kb mRNA species strongly and exclusively expressed in the testis. We cloned the corresponding full-length cDNA, which encodes a predicted polypeptide of 551 amino acids with at least two potential transmembrane domains and a tyrosine phosphatase motif. The cDNA has sequence homology to chicken tensin, bovine auxilin and rat cyclin-G associated kinase (GAK). The entire polypeptide sequence also has significant homology to tumor suppressor PTEN/MMAC1 protein. We termed this novel gene/protein TPTE (transmembrane phosphatase with tensin homology). Polymerase chain reaction amplification, fluorescent in situ hybridization, Southern-blot and sequence analysis using monochromosomal somatic cell hybrids showed that this gene has highly homologous copies on HC13, 15, 22, and Y, in addition to its HC21 copy or copies. The estimated minimum number of copies of the TPTE gene in the haploid human genome is 7 in male and 6 in female. Zoo-blot analysis showed that TPTE is conserved between humans and other species. The biological function of the TPTE gene is presently unknown; however, its expression pattern, sequence homologies, and the presence of a potential tyrosine phosphatase domain suggest that it may be involved in signal transduction pathways of the endocrine or spermatogenetic function of the testis. It is also unknown whether all copies of TPTE are functional or whether some are pseudogenes. TPTE is, to our knowledge, the gene located closest to the human centromeric sequences.

Presence of an SH2 domain in the actin-binding protein tensin.

The molecular cloning of the complementary DNA coding for a 90-kilodalton fragment of tensin, an actin-binding component of focal contacts and other submembraneous cytoskeletal structures, is reported. The derived amino acid sequence revealed the presence of a Src homology 2 (SH2) domain. This domain is shared by a number of signal transduction proteins including nonreceptor tyrosine kinases such as Abl, Fps, Src, and Src family members, the transforming protein Crk, phospholipase C-gamma 1, PI-3 (phosphatidylinositol) kinase, and guanosine triphosphatase-activating protein (GAP). Like the SH2 domain found in Src, Crk, and Abl, the SH2 domain of tensin bound specifically to a number of phosphotyrosine-containing proteins from v-src-transformed cells. Tensin was also found to be phosphorylated on tyrosine residues. These findings suggest that by possessing both actin-binding and phosphotyrosine-binding activities and being itself a target for tyrosine kinases, tensin may link signal transduction pathways with the cytoskeleton.