Prognostic role of sex steroid receptors in pancreatic adenocarcinoma

Chloroxine inhibits pancreatic cancer progression through targeted antagonization of the PI3K/AKT/mTOR signaling pathway

BACKGROUND

Patients with pancreatic cancer have a dismal prognosis due to tumor cell infiltration and metastasis. Many reports have documented that EMT and PI3K-AKT-mTOR axis control pancreatic cancer cell infiltration and metastasis. Chloroxine is an artificially synthesized antibacterial compound that demonstrated anti-pancreatic cancer effects in our previous drug-screening trial. We have explored the impact of chloroxine on pancreatic cancer growth, infiltration, migration, and apoptosis.

METHODS

The proliferation of pancreatic cancer cell lines (PCCs) treated with chloroxine was assessed through real-time cell analysis (RTCA), colony formation assay, CCK-8 assay, as well as immunofluorescence. Chloroxine effects on the infiltrative and migratory capacities of PCCs were assessed via Transwell invasion and scratch experiments. To assess the contents of EMT- and apoptosis-associated proteins in tumor cells, we adopted Western immunoblotting as well as immunofluorescence assays, and flow cytometry to determine chloroxine effects on PCCs apoptosis. The in vivo chloroxine antineoplastic effects were explored in nude mice xenografts.

RESULTS

Chloroxine repressed pancreatic cancer cell growth, migration, and infiltration in vitro, as well as in vivo, and stimulated apoptosis of the PCCs. Chloroxine appeared to inhibit PCC growth by Ki67 downregulation; this targeted and inhibited aberrant stimulation of the PI3K-AKT-mTOR signaling cascade, triggered apoptosis in PCC via mitochondria-dependent apoptosis, and modulated the EMT to inhibit PCC infiltration and migration.

CONCLUSIONS

Chloroxine targeted and inhibited the PI3K-AKT-mTOR cascade to repress PCCs growth, migration, as well as invasion, and triggered cellular apoptosis. Therefore, chloroxine may constitute a potential antineoplastic drug for the treatment of pancreatic cancer.

Gynecological and reproductive factors and the risk of pancreatic cancer: A case-control study

BACKGROUND

/Objectives: Pancreatic ductal adenocarcinoma (PDAC) has a higher incidence in men compared to women, although the difference in known risk factors cannot explain this disparity completely. Reproductive and hormonal factors have been demonstrated in pre-clinical studies to influence pancreatic carcinogenesis, but the few published data on the topic are inconsistent. The aim was to investigate the role of reproductive and hormonal factors on PDAC occurrence in women.

METHODS

We conducted a unicenter case-control study; PDAC cases were matched to controls by age with a 1:2 ratio. Risk factors were screened through questionnaires about gynecologic and medical history. Comparisons were made using Chi-square and Fisher's exact tests where appropriate for categorical variables and Student's t-test for continuous variables. Logistic regression was used to calculate Odds Ratios (ORs) and their 95% confidence intervals (CI). Multivariable logistic regression models were adjusted for potential confounders.

RESULTS

253 PDAC and 506 matched controls were enrolled. At logistic regression multivariable analysis adjusted for confounding factors, older age at menopause (OR:0.95 per year; 95% CI:0.91-0.98; p = 0.007), use of Oral Contraceptives (OR:0.52; 95% CI:0.30-0.89; p = 0.018), use of Hormonal Replacement Therapy (OR:0.31; 95% CI:0.15-0.64; p = 0.001), and having had two children (OR:0.57; 95% CI:0.38-0.84; p = 0.005) were significant, independent protective factors for the onset of PDAC.

CONCLUSIONS

These data confirm some previous findings on menopause age and number of births while, to our knowledge, this is the first study to show a protective effect of HRT and OC use. The results collectively support the hypothesis that exposure to estrogens plays a protective role towards PDAC.

Important roles of estrogen receptor alpha in tumor progression and anti-estrogen therapy of pancreatic ductal adenocarcinoma

AIMS

The roles of estrogen receptors (ERs) and the efficacy of anti-estrogen (E2) therapies in pancreatic cancer stay controversial. The main objectives of this study were to investigate the potential roles of ERs in tumor progression and endocrine therapies.

MAIN METHODS

The ER expression status in PANC-1 and SW1990 pancreatic cancer cell lines was determined. SRB assay, colony formation assay and proliferation assay were used to investigate the responses of these cells to E2. ERα-selective agonist propylpyrazoletriol (PPT), ERβ-selective agonist diarylpropionitrile (DPN), ERα over-expressed SW1990 cells, ERα knock-out PANC-1 cells and patient-derived xenografts (PDX) were applied to investigate the potential roles of ERα in pancreatic cancer. The phosphorylation of ERα-related signaling molecules extracellular regulated protein kinases (ERK1/2) and protein kinase B (AKT) were investigated. The in vivo anti-tumor efficacy and safety of letrozole (LTZ) combined with leuprorelin acetate (LA) and gemcitabine (GEM) were also preliminarily studied.

KEY FINDINGS

PANC-1 cells expressed much more ERα than SW1990 cells, and ERβ level was with less diversity. Accordingly, the proliferation of PANC-1 rather than SW1990 cells could be stimulated by E2, and only PANC-1 could respond to LTZ endocrine therapy in female but not male mice. The phosphorylation of ERK1/2 but not AKT was altered by over-expressed or knocking out of ERα with or without the addition of E2 and LTZ. The combination therapy of LTZ and GEM showed acceptable efficacy and safety.

SIGNIFICANCE

This study showed the important roles of ERα in tumor progression and endocrine therapies of pancreatic cancer in women.

Clinical significance of stromal ER and PR expression in periampullary adenocarcinoma

BACKGROUND

Tamoxifen treatment has previously been reported to confer life-prolonging effects in patients with advanced pancreatic cancer, and most evidently so in women. None of these trials did however include biomarkers, and the relevance of female hormone signaling in pancreatic or other periampullary adenocarcinoma remains largely unexplored. The aim of this study was to examine the extent and potential clinical significance of estrogen receptor-α (ER) and progesterone receptor (PR) expression in pancreatic and other periampullary cancers.

METHODS

ER and PR expression was examined using immunohistochemistry on tissue microarrays with primary tumors from a retrospective consecutive cohort of 175 patients with resected periampullary adenocarcinoma, with long-term clinical follow-up. Non-parametric and Chi square tests were applied to examine the associations of stromal ER and PR expression with patient and tumor characteristics. Kaplan-Meier analysis and log rank test were applied to illustrate survival differences in relation to ER and PR expression. Cox regression proportional hazards models were applied to examine the associations between investigative factors and risk of death and recurrence, and to test for interactions between KRAS mutation status and hormone receptor expression in relation to survival.

RESULTS

Expression of both ER and PR was more frequent in the tumor-associated stroma than in the epithelium. A significant prognostic interaction, independent of tumor morphology, was found between stromal PR expression and KRAS mutation status in relation to both overall and recurrence-free survival (pinteraction = 0.026 and pinteraction = 0.005), in particular in women (pinteraction = 0.002 and pinteraction = 0.005). Specifically, stromal PR expression was associated with a prolonged survival in patients with KRAS-mutated tumors, whereas the opposite was seen for KRAS wild-type tumors. The prognostic value of ER positivity was limited to the subgroup of women with tumors of pancreatic origin.

CONCLUSIONS

These results demonstrate that stromal PR rather than ER expression, together with KRAS mutation status, provides long-term prognostic information in patients with periampullary adenocarcinoma. Further study into the mechanistic basis for these observations may unveil important clues to the pathogenesis of these cancers and open up for the discovery of novel treatment options.

Potential ceRNA networks involved in autophagy suppression of pancreatic cancer caused by chloroquine diphosphate: A study based on differentially‑expressed circRNAs, lncRNAs, miRNAs and mRNAs

Autophagy has been reported to be involved in the occurrence and development of pancreatic cancer. However, the mechanism of autophagy‑associated non‑coding RNAs (ncRNAs) in pancreatic cancer remains largely unknown. In the present study, microarrays were used to detect differential expression of mRNAs, microRNAs (miRNAs), long ncRNAs (lncRNAs) and circular RNAs (circRNAs) post autophagy suppression by chloroquine diphosphate in PANC‑1 cells. Collectively, 3,966 mRNAs, 3,184 lncRNAs and 9,420 circRNAs were differentially expressed. Additionally, only two miRNAs (hsa‑miR‑663a‑5p and hsa‑miR‑154‑3p) were underexpressed in the PANC‑1 cells in the autophagy‑suppression group. Furthermore, miR‑663a‑5p with 9 circRNAs, 8 lncRNAs and 46 genes could form a prospective ceRNA network associated with autophagy in pancreatic cancer cells. In addition, another ceRNA network containing miR‑154‑3p, 5 circRNAs, 2 lncRNAs and 11 genes was also constructed. The potential multiple ceRNA, miRNA and mRNA associations may serve pivotal roles in the autophagy of pancreatic cancer cells, which lays the theoretical foundation for subsequent investigations on pancreatic cancer.

Pancreatic cancer: A review of clinical diagnosis, epidemiology, treatment and outcomes

This review aims to outline the most up-to-date knowledge of pancreatic adenocarcinoma risk, diagnostics, treatment and outcomes, while identifying gaps that aim to stimulate further research in this understudied malignancy. Pancreatic adenocarcinoma is a lethal condition with a rising incidence, predicted to become the second leading cause of cancer death in some regions. It often presents at an advanced stage, which contributes to poor five-year survival rates of 2%-9%, ranking firmly last amongst all cancer sites in terms of prognostic outcomes for patients. Better understanding of the risk factors and symptoms associated with this disease is essential to inform both health professionals and the general population of potential preventive and/or early detection measures. The identification of high-risk patients who could benefit from screening to detect pre-malignant conditions such as pancreatic intraepithelial neoplasia, intraductal papillary mucinous neoplasms and mucinous cystic neoplasms is urgently required, however an acceptable screening test has yet to be identified. The management of pancreatic adenocarcinoma is evolving, with the introduction of new surgical techniques and medical therapies such as laparoscopic techniques and neo-adjuvant chemoradiotherapy, however this has only led to modest improvements in outcomes. The identification of novel biomarkers is desirable to move towards a precision medicine era, where pancreatic cancer therapy can be tailored to the individual patient, while unnecessary treatments that have negative consequences on quality of life could be prevented for others. Research efforts must also focus on the development of new agents and delivery systems. Overall, considerable progress is required to reduce the burden associated with pancreatic cancer. Recent, renewed efforts to fund large consortia and research into pancreatic adenocarcinoma are welcomed, but further streams will be necessary to facilitate the momentum needed to bring breakthroughs seen for other cancer sites.

Tamoxifen Never Ceases to Amaze: New Findings on Non-Estrogen Receptor Molecular Targets and Mediated Effects

Tamoxifen is a first targeted drug that continues to be the gold standard in treatment of estrogen receptor positive breast cancer for almost 50 years. The current review is an update of the paper published in 2012. We provide the new data on the tamoxifen targets that are the key points of signaling cascades activating cellular proliferation, which determines aggressiveness of disease and chemotherapy resistance or sensitivity. Some inspiring clinical cases dealing with tamoxifen efficiency in treatment of different tumors are discussed. Additionally, the review includes data on antiviral, antibacterial, antifungal and antiparasitic activity of tamoxifen.

Menstrual and Reproductive Factors and Risk of Pancreatic Cancer in Women

BACKGROUND

Pancreatic cancer (PC) is a deadly disease with a 5-year survival of less than 5%. Worldwide PC incidence rates are lower among women than men. While this suggests a protective role for steroid hormones in PC risk, results from epidemiological studies are not consistent.

METHODS

153 new incident PC cases and 202 controls were recruited from a prospective case–control study, running in a referral center for endoscopic ultrasonography during 2011-2017. A structured valid and reliable questionnaire was used for data collection by a few trained interviewers. Odds ratios and 95% confidence intervals for reproductive factors and PC were estimated using logistic regression methods.

RESULTS

Mean age (SD) of the cases and the controls were 63.18 (11.4) and 63.37 (12.0) years, respectively. Age at menarche, age at menopause, number of parity, gravidity, and abortion were not associated with PC risk.

CONCLUSION

This study does not support the hypothesis that menstrual and reproductive factors are associated with PC risk.