Chemo/Dietary prevention of cancer: perspectives in China

DSG2 expression is low in colon cancer and correlates with poor survival

Background

Desmoglein2 (DSG2) is a transmembrane protein that helps regulate intercellular connections and contributes to desmosome assembly. Desmosome are associated with cell adhesion junctions, which play an important role in cancer progression specially cancer cell migration and invasion. However, DSG2 expression in colon cancer (CC) and its association with CC patients’ overall survival (OS) are still unclear.

Methods

We collected 587 CC samples, 41 colitis tissues and 114 pericarcinomatous tissues, as well as corresponding clinicopathological data about the patients who contributed them. All samples were tested immunohistochemically in tissue microarrays. Kaplan–Meier method was used for calculating patient survival. Univariate and multivariate analyses was used for investigating DGS2 link with CC patient’s clinicopathological factors. Bioinformatics analysis was also used in study.

Results

The results showed that DSG2 expression was lower in CC tissues than in pericarcinomatous tissues (P < 0.001). DSG2 expression was associated with differentiation (P = 0.033), lymph node metastasis (P = 0.045), distant metastasis (P = 0.006) and AJCC stage (P < 0.001). Univariate analysis indicated that poor OS in patients with CC was associated with low DSG2 expression (P < 0.001), tumor size (P < 0.001), lymph node metastasis (P < 0.001), distant metastasis (P < 0.001), AJCC stage (P < 0.001) and venous invasion (P < 0.001). In multivariate analysis, low DSG2 expression (P < 0.001), distant metastasis (P < 0.001), AJCC stage (P = 0.002), venous invasion (P < 0.001) were independent prognostic factors for CC patients. Bioinformatics analysis indicated that low DSG2 expression affects protein activation, regulates the P53-related pathway in CC, and activates the EGFR pathway.

Conclusions

The results suggest that low DSG2 expression is associated with poor survival for CC patients. DSG2 could be a prognostic biomarker for CC.

Triptorelin relieves lower urinary tract symptoms in Chinese advanced prostate cancer patients: a multicenter, non-interventional, prospective study

BACKGROUND

Although triptorelin is increasingly used in China for biochemical castration, its effects on primary prostate cancer symptoms remain unclear. This study aimed to assess the prevalence of lower urinary tract symptoms (LUTS) in Chinese prostate cancer patients and the effectiveness of triptorelin on LUTS.

METHODS

In this 48-week multicenter, non-interventional, prospective study, we enrolled patients with locally advanced or metastatic prostate cancer. Patients received triptorelin (15 mg) intramuscularly at baseline and at weeks 12, 24, and 36 with symptom assessment using the International Prostate Symptoms Score (IPSS). The primary endpoints were the prevalence of LUTS at baseline per IPSS categories and the percentage of patients with moderate to severe LUTS (IPSS > 7) at baseline, having at least a 3-point reduction of IPSS score at week 48.

RESULTS

A total of 398 patients were included; 211 (53.0%) and 160 (40.2%) among them had severe and moderate LUTS, respectively. Of the patients with IPSS scores available at baseline and at week 48 (n = 213), 81.2% achieved a reduction in IPSS of at least 3 points. Of the patients with moderate to severe LUTS at baseline and IPSS scores available at baseline and at week 48 (n = 194), 86.6% achieved a total IPSS reduction of at least 3 points.

CONCLUSIONS

The vast majority of Chinese patients with locally advanced or metastatic prostate cancer scheduled to receive triptorelin as part of their standard treatment have severe or moderate LUTS. Triptorelin therapy resulted in sustained improvement of LUTS in these patients.

NEAT1 upregulates EGCG-induced CTR1 to enhance cisplatin sensitivity in lung cancer cells

Platinum-based drugs are the firstline of treatment for non-small cell lung cancer (NSCLC), but resistance to these drugs is a major obstacle to effective chemotherapy. Our previous study revealed that the green tea polyphenol, EGCG, induced cisplatin transporter CTR1 (copper transporter 1) and enhanced cisplatin sensitivity in ovarian cancer. In this study, we found that EGCG upregulated CTR1 and increased platinum accumulation in NSCLC (A549, H460 and H1299) cells, cDDP-resistant A549 cells and a nude mouse xenograft model. Cisplatin-induced inhibition of cell growth was enhanced by EGCG treatment in vitro and in vivo. MicroRNA hsa-mir-98-5p appears to suppress CTR1 gene expression, while long non-coding RNA (lncRNA) nuclear enriched abundant transcript 1 (NEAT1) appears to enhance it. Bioinformatics analysis showed that hsa-mir-98-5p has specific complementary binding sites for NEAT1. In addition, hsa-mir-98-5p was predicted to be a putative CTR1 target. NEAT1 may act as a competing endogenous lncRNA to upregulate EGCG-induced CTR1 by sponging hsa-mir-98-5p in NSCLC. Our findings reveal a novel mechanism how NEAT1 upregulates EGCG-induced CTR1 and enhances cisplatin sensitivity in vitro and in vivo, and suggest EGCG could serve as an effective adjuvant chemotherapeutic in lung cancer treatment.

Association of three single nucleotide polymorphisms of ESR1with breast cancer susceptibility: a meta-analysis

Expression of estrogen receptors is correlated with breast cancer risk, but inconsistent results have been reported. To clarify potential estrogen receptor (ESR)-related breast cancer risk, we analyzed genetic variants of ESR1 in association with breast cancer susceptibility. We performed a meta-analysis to investigate the association between rs2234693, rs1801132, and rs2046210 (single nucleotide polymorphisms of ESR1 ), and breast cancer risk. Our analysis included 44 case-control studies. For rs2234693, the CC genotype had a higher risk of breast cancer compared to the TT or CT genotype. For rs2046210, the AA, GA, or GA+ GG genotype had a much higher risk compared to the GG genotype. No significant association was found for the rs1801132 polymorphism with breast cancer risk. This meta-analysis demonstrates association between the rs2234693 and rs2046210 polymorphisms of ESR1 and breast cancer risk. The correlation strength between rs2234693 and breast cancer susceptibility differs in subgroup assessment by ethnicity.

TXR1 and TSP1 expression varies by the molecular subtypes of breast cancer patients who received previous docetaxel-based first-line chemotherapy

The expression of taxol resistance gene 1 and thrombospondin 1 remains unknown in human breast cancer tissues. In the current study, we sought to measure the mRNA expression levels of taxol resistance gene 1 and thrombospondin 1 in breast cancer tissue and adjacent normal tissue specimens and further analyzed their expression according to the molecular subtypes and age of breast cancer patients who had received taxane-containing regimens. Archived breast cancer and adjacent non-tumor tissue specimens were obtained at Beijing Friendship Hospital, Beijing, China. The mRNA transcript levels of taxol resistance gene 1, thrombospondin 1 and multi-drug resistance 1 were determined by quantitative RT-PCR. Taxol resistance gene 1 and multi-drug resistance 1 protein levels were measured by immunoblotting assays. Forty-nine archived breast cancer tissue specimens were included. The majority of the specimens (65.3%) were of the molecular subtype A followed by triple negative breast cancer (14.3%). The mRNA transcript levels of taxol resistance gene 1 , thrombospondin 1 and multi-drug resistance 1 in breast cancer tissues were higher than those of adjacent normal tissues. The mRNA expression of TXR1 in the HER2 subtype (4.513 ± 0.810) was the highest and in the Luminal B subtype was the lowest (3.103 ± 0.417) among the four molecular subtypes. The HER2 subtype also had the highest mRNA expression of thrombospondin 1(4.827 ± 0.927) and the Luminal B subtype had the lowest TSP1 mRNA level (3.197 ± 0.565) among the four molecular subtypes. Our study represents the first attempt in delineating taxol resistance gene 1 and thrombospondin 1 expression in breast cancer and we demonstrate that taxol resistance gene 1 and thrombospondin 1 expression may vary according to the molecular subtypes of breast cancer.

Dietary compound isoliquiritigenin prevents mammary carcinogenesis by inhibiting breast cancer stem cells through WIF1 demethylation

Breast cancer stem cells (CSCs) are considered as the root of mammary tumorigenesis. Previous studies have demonstrated that ISL efficiently limited the activities of breast CSCs. However, the cancer prevention activities of ISL and its precise molecular mechanisms remain largely unknown. Here, we report a novel function of ISL as a natural demethylation agent targeting WIF1 to prevent breast cancer. ISL administration suppressed in vivo breast cancer initiation and progression, accompanied by reduced CSC-like populations. A global gene expression profile assay further identified WIF1 as the main response gene of ISL treatment, accompanied by the simultaneous downregulation of β-catenin signaling and G0/G1 phase arrest in breast CSCs. In addition, WIF1 inhibition significantly relieved the CSC-limiting effects of ISL and methylation analysis further revealed that ISL enhanced WIF1 gene expression via promoting the demethylation of its promoter, which was closely correlated with the inhibition of DNMT1 methyltransferase. Molecular docking analysis finally revealed that ISL could stably dock into the catalytic domain of DNMT1. Taken together, our findings not only provide preclinical evidence to demonstrate the use of ISL as a dietary supplement to inhibit mammary carcinogenesis but also shed novel light on WIF1 as an epigenetic target for breast cancer prevention.

EGCG Enhances Cisplatin Sensitivity by Regulating Expression of the Copper and Cisplatin Influx Transporter CTR1 in Ovary Cancer

Cisplatin is one of the first-line platinum-based chemotherapeutic agents for treatment of many types of cancer, including ovary cancer. CTR1 (copper transporter 1), a transmembrane solute carrier transporter, has previously been shown to increase the cellular uptake and sensitivity of cisplatin. It is hypothesized that increased CTR1 expression would enhance the sensitivity of cancer cells to cisplatin (cDDP). The present study demonstrates for the first time that (-)-epigallocatechin-3-gallate (EGCG), a major polyphenol from green tea, can enhance CTR1 mRNA and protein expression in ovarian cancer cells and xenograft mice. EGCG inhibits the rapid degradation of CTR1 induced by cDDP. The combination of EGCG and cDDP increases the accumulation of cDDP and DNA-Pt adducts, and subsequently enhances the sensitivity of ovarian cancer SKOV3 and OVCAR3 cells to the chemotherapeutic agent. In the OVCAR3 ovarian cancer xenograft nude mice model, the combination of the lower concentration of cDDP and EGCG strongly repressed the tumor growth and exhibited protective effect on the nephrotoxicity induced by cisplatin. Overall, these findings uncover a novel chemotherapy mechanism of EGCG as an adjuvant for the treatment of ovarian cancer.