Prognostic impact of vascular endothelial growth factor-A expression in resected gallbladder carcinoma

Gallbladder cancer: surgical treatment, immunotherapy, and targeted therapy

Gallbladder cancer is a common type of biliary tract tumor. Optimal management for early stage cases typically involves radical excision as the primary treatment modality. Various surgical techniques, including laparoscopic, robotic, and navigational surgery, have demonstrated favorable clinical outcomes in radical gallbladder excision. Unfortunately, most patients are ineligible for surgical intervention because of the advanced stage of the disease upon diagnosis. Consequently, non-surgical interventions, such as chemotherapy, radiotherapy, immunotherapy, and targeted therapy, have become the mainstay of treatment for patients in advanced stages. This review focuses on elucidating various surgical techniques as well as advancements in immunotherapy and targeted therapy in the context of recent advancements in gallbladder cancer research.

Clinicopathological and prognostic significance of VEGF, PDGF-B, and HER2/neu expression in gallbladder cancer

AIM

Gallbladder cancer (GBC) is usually diagnosed in advanced stages with poor survival. The molecular mechanisms of GBC still remain unexplored. Several angiogenesis factors play a pivotal role in tumor progression. We aimed to study the expression of VEGF, PDGF-B, and human epidermal growth factor receptor 2 (HER2/neu) and its association with clinicopathological features and survival in GBC.

MATERIALS AND METHODS

VEGF, PDGF-B, and HER2/neu expression was studied by immunohistochemistry (IHC) after histological evaluation in 91 GBC cases. The relationship between these markers and clinicopathological features and survival was explained through the Cox regression model and Kaplan-Meier method.

RESULTS

VEGF, PDGF-B, and HER2/neu overexpressed in 45, 79, and 68% GBC cases, respectively. VEGF was significantly overexpressed in GBC without gall stones (GS) (p = 0.007) and with moderately and poorly differentiated tumors (p = 0.012). HER2/neu was significantly overexpressed in GBC with GS (p = 0.022). Median overall survival (OS) was 39 months (95% CI: 23-55). In univariate analysis, histological type (adenocarcinoma and papillary) vs. others (signet ring/mucinous/adenosquamous) (p = 0.004), depth of tumor infiltration (p = 0.017), distant metastasis (p = 0.012), and adjuvant therapies (chemotherapy/radiotherapy) (p = 0.083) were associated with poor prognosis. Multivariate survival analysis showed histological type (p = 0.004) and distant metastasis (p = 0.032) to be independent prognostic factors for OS. Histological type (p = 0.002), distant metastasis (p = 0.003), and depth of tumor infiltration (T3-T4) (p = 0.012) showed poor median survival. Poor survival was seen in VEGF and HER2/neu positive cases.

CONCLUSION

Overexpression of VEGF, PDGF-B, and HER2/neu might be possible prognostic biomarkers in GBC. Poor survival of VEGF and HER2/neu positive cases indicates the possibilities of using their blockers as therapeutic agents.

Krukenberg Tumor Related to Gallbladder Cancer in a Young Woman: A Case Report and Review of the Literature

A gallbladder tumor is a rare condition, which usually spreads to the liver, lymph nodes, and other organs. A Krukenberg tumor, derived from the biliary tract and gallbladder cancers (GBCs), is an uncommon finding in routine clinical practice. Here, a case of a young woman with a Krukenberg tumor related to a previous diagnosis of GBC is reported. Differential diagnosis of an ovarian malignant lesion is challenging for both clinicians and pathologists. In order to provide a proper diagnosis, integrated multidisciplinary management is essential. The occurrence of Krukenberg tumors should be evaluated in the management of GBC, even if this is rare in clinical practice.

Chemo-Free Treatment Using Anti-PD-1 Antibodies with Lenvatinib in Unresectable Gallbladder Cancer: PD-L1 May Be a Potential Biomarker for a Better Outcome

BACKGROUND

Recently, anti-PD-1 antibodies plus lenvatinib has been administered in a series of solid tumors. Yet, the efficacy of chemo-free treatment of this combined therapy has seldom been reported in gallbladder cancer (GBC). The aim of our study was to initially evaluate the efficacy of the chemo-free treatment in unresectable GBCs.

METHODS

We retrospectively collected the clinical data of unresectable GBCs treated using chemo-free anti-PD-1 antibodies plus lenvatinib in our hospital from March 2019 to August 2022. The clinical responses were assessed, and PD-1 expression was evaluated.

RESULTS

Our study enrolled 52 patients, with the median progression-free survival being 7.0 months and the median overall survival being 12.0 months. The objective response rate was 46.2% and the disease control rate was 65.4%. The expression of PD-L1 in patients with objective response was significantly higher than those with progression of disease.

CONCLUSIONS

For patients with unresectable GBC, when not eligible for systemic chemotherapy, chemo-free treatment using anti-PD-1 antibodies with lenvatinib may become a safe and rational choice. The expression of PD-L1 in tumor tissues may be correlated to the objective response, and thus is expected to be a predictor of efficacy, and further clinical studies are certainly needed.

Targeting Angiogenesis in the Era of Biliary Tract Cancer Immunotherapy: Biological Rationale, Clinical Implications, and Future Research Avenues

Although biliary tract cancers are traditionally considered rare in Western countries, their incidence and mortality rates are rising worldwide. A better knowledge of the genomic landscape of these tumor types has broadened the number of molecular targeted therapies, including angiogenesis inhibitors. The role of immune checkpoint inhibitors (ICIs) could potentially change the first-line therapeutic approach, but monotherapy with ICIs has shown disappointing results in CCA. Several clinical trials are evaluating combination strategies that include immunotherapy together with other anticancer agents with a synergistic activity. The tumor microenvironment (TME) composition plays a pivotal role in the prognosis of BTC patients. The accumulation of immunosuppressive cell types, such as tumor-associated macrophages (TAMs) and regulatory T-cells, together with the poor infiltration of cytotoxic CD8+ T-cells, is known to predispose to a poor prognosis owing to the establishment of resistance mechanisms. Likewise, angiogenesis is recognized as a major player in modulating the TME in an immunosuppressive manner. This is the mechanistic rationale for combination treatment schemes blocking both immunity and angiogenesis. In this scenario, this review aims to provide an overview of the most recent completed or ongoing clinical trials combining immunotherapy and angiogenesis inhibitors with/without a chemotherapy backbone.

Gallbladder Cancer: Current Multimodality Treatment Concepts and Future Directions

Gallbladder cancer (GBC) is the most common primary tumor site of biliary tract cancer (BTC), accounting for 0.6% of newly diagnosed cancers and 0.9% of cancer-related deaths. Risk factors, including female sex, age, ethnic background, and chronic inflammation of the gallbladder, have been identified. Surgery is the only curative option for early-stage GBC, but only 10% of patients are primary eligible for curative treatment. After neoadjuvant treatment, up to one-third of locally advanced GBC patients could benefit from secondary surgical treatment. After surgery, only a high-risk subset of patients benefits from adjuvant treatment. For advanced-stage GBC, palliative chemotherapy with gemcitabine and cisplatin is the current standard of care in line with other BTCs. After the failure of gemcitabine and cisplatin, data for second-line treatment in non-resectable GBC is poor, and the only recommended chemotherapy regimen is FOLFOX (5-FU/folinic acid and oxaliplatin). Recent advances with the PD-L1 inhibitor durvalumab open the therapy landscape for immune checkpoint inhibition in GBC. Meanwhile, targeted therapy approaches are a cornerstone of GBC therapy based on molecular profiling and new evidence of molecular differences between different BTC forms and might further improve the prognosis of GBC patients.

HMGA2 promotes the migration and invasion of gallbladder cancer cells and HMGA2 knockdown inhibits angiogenesis via targeting VEGFA

The high mobility group AT-hook 2 (HMGA2) protein has been found to be upregulated in the majority of tumor types and is associated with a poor prognosis. Previous studies have suggested the oncogenic role of HMGA2 in gallbladder cancer (GBC). The present study aimed to investigate the effects of HMGA2 on the invasion, migration and angiogenesis of GBC cells. To achieve this aim, HMGA2 was overexpressed or silenced in the GBC cell line, EH-GB1, and then the proliferation, migration, invasion and epithelial-mesenchymal transition (EMT) abilities of EH-GB1 cells were investigated using Cell Counting Kit-8, wound healing, Transwell and western blotting assays. In addition, the expression levels of VEGFA were determined in EH-GB1 cells using western blotting and reverse transcription-quantitative PCR following HMGA2 overexpression or silencing. Furthermore, HMGA2-silenced EH-GB1 cells were transfected with VEGFA overexpression plasmids to evaluate the tube formation ability of HUVECs using tube formation assay. The results demonstrated that HMGA2 silencing inhibited GBC cell proliferation, migration, invasion and EMT, as evidenced by the downregulated expression of Ki67, proliferating cell nuclear antigen, MMP2, MMP9, N-cadherin, snail family transcriptional repressor 2 and zinc finger E-box-binding homeobox 1, and attenuated cell migration and invasion. However, the opposite results were obtained following HMGA2 overexpression. Moreover, HMGA2 knockdown and overexpression downregulated and upregulated VEGFA expression, respectively. In addition, the tube formation ability of HUVECs and the expression levels of CD31, VEGFR1 and VEGFR2 were downregulated following HMGA2 silencing. However, these effects were partially rescued by simultaneous VEGFA overexpression. In conclusion, the findings of the present study revealed that HMGA2 may promote GBC cell migration, invasion, EMT and angiogenesis. Therefore, inhibiting HMGA2 expression could be considered as a possible therapeutic approach for GBC.

Molecular Targets and Emerging Therapies for Advanced Gallbladder Cancer

Biliary tract cancers (BTCs), for their low incidence, have been often considered together. Gallbladder cancer (GBC) is the most common biliary tract malignancy, characterized by late diagnosis and poor prognosis, and although it is considered a rare tumor in western countries, other areas of the world show considerable incidence rates. In 2010, results from the large phase III ABC-02 clinical trial on GBC identified the gemcitabine and cisplatin combination as the most effective first-line regimen for both GBC and other BTCs. Since then, various systemic therapies have proven active in BTCs in both first- and second-line settings. Molecular profiling has highlighted important genetic differences between GBC and other BTCs, opening new ways for targeted therapy in advanced disease where standard chemotherapies show marginal benefit. Genome-wide data analysis have shown that GBC molecular landscape offer possible strategies for precision medicine approaches, and a better molecular understanding of the GBC is needed to better stratify patients for treatment. In this review, we discuss the molecular targetable agents for GBC, including the results that emerged by clinical trials exploring new treatment strategies.

Recent Advances in the Mechanism Research and Clinical Treatment of Anti-Angiogenesis in Biliary Tract Cancer

Biliary tract cancers (BTCs), including cholangiocarcinoma (CCA) and gallbladder cancer (GC), are malignancies originating from the biliary tract with poor prognosis. In the early stage of BTCs, surgery is the only choice for cure. Unfortunately, most patients with BTC are diagnosed at an advanced stage and lose the opportunity for surgery. For many advanced solid tumors, antiangiogenic therapy has achieved encouraging results. While most clinical studies on antiangiogenic therapy in advanced BTCs have shown an excellent disease control rate (DCR), the improvement in overall survival (OS) is controversial. Understanding how the relevant signaling molecules influence the angiogenic response and the functional interaction is necessary for the formulation of new treatment regimens and the selection of enrolled patients. In this review, we aim to summarize and discuss the latest advances in antiangeogenesis for BTCs, mainly focusing on the molecular mechanism of angiogenesis in BTCs and the therapeutic effects from clinical trials. Furthermore, the horizon of antiangiogenesis for BTCs is highlighted.

Molecular Oncology of Gall Bladder Cancer

Gall bladder carcinoma (GBC) is a worldwide problem, with a higher incidence in areas of the world where cholelithiasis is common. As GBC is usually diagnosed in an advanced stage, the mortality is high. An understanding of the molecular pathways of carcinogenesis and the mutations involved in the development and progression of GBC could be useful in early diagnosis. Understanding molecular markers of prognosis as well as predictors of outcome could also potentially benefit patients undergoing treatment. New therapies targeting major molecular pathways and immunotherapy are exciting novel therapeutic options. This review focuses on the current understanding of the molecular oncology of GBC.

Overview of current targeted therapy in gallbladder cancer

Gallbladder cancer (GBC) is rare, but is the most malignant type of biliary tract tumor. Unfortunately, only a small population of cancer patients is acceptable for the surgical resection, the current effective regimen; thus, the high mortality rate has been static for decades. To substantially circumvent the stagnant scenario, a number of therapeutic approaches owing to the creation of advanced technologic measures (e.g., next-generation sequencing, transcriptomics, proteomics) have been intensively innovated, which include targeted therapy, immunotherapy, and nanoparticle-based delivery systems. In the current review, we primarily focus on the targeted therapy capable of specifically inhibiting individual key molecules that govern aberrant signaling cascades in GBC. Global clinical trials of targeted therapy in GBC are updated and may offer great value for novel pathologic and therapeutic insights of this deadly disease, ultimately improving the efficacy of treatment.

Tumor Marker Kinetics as Prognosticators in Patients with Unresectable Gallbladder Adenocarcinoma Undergoing Palliative Chemotherapy

Background/Aims

To determine the prognostic value of carcinoembryonic antigen (CEA) and carbohydrate antigen (CA) 19-9 in gallbladder cancer (GBC) during palliative chemotherapy.

Methods

One hundred and twenty-three patients with pathologically confirmed unresectable GBC were included. Differences in serum CEA and CA 19-9 levels before and after chemotherapy were measured. Receiver operating characteristic curve analysis, Kaplan-Meier analyses of CEA, CA 19-9, and combined changes were performed to assess the optimal cutoff values and survival rates.

Results

Patients with decreased tumor markers had significantly better progression-free survival (PFS) and overall survival (OS) than patients with increased tumor markers. The pre- and postchemotherapy CA 19-9 ratio had the highest area-under-the-curve values for predicting 3-month PFS and 1-year OS. In the multivariate analysis, increases in serum CA 19-9 during palliative chemotherapy in patients with unresectable GBC was an independent prognosticator of poor PFS and OS, with hazard ratios of 2.20 (p=0.001) and 1.67 (p=0.020), respectively. Patients with increases >10-fold were considered to have progressive disease, whereas individuals with increases >3-fold were likely to benefit from early imaging follow-up.

Conclusions

CA 19-9 kinetics was a reliable prognosticator of PFS and OS in patients with unresectable GBC who underwent palliative chemotherapy.

Investigation of targetable predictive and prognostic markers in gallbladder carcinoma

Background

Gallbladder carcinoma, uncommon in most of the world, is frequent in South East Asia. It presents in advanced stages with limited therapeutic options. We investigated targetable predictive and prognostic Markers in 268 cases including 233 primary site lesions and 35 metastatic gallbladder carcinoma.

Methods

EGFR, VEGF, HER2/Neu and p53 were assessed using immunohistochemistry. HER2/Neu was validated in a subset by fluorescent in situ hybridization (FISH) using tissue microarray (TMA). Broader spectrum of gene variation was screened in NGS in representative FFPE tissue using the Ion AmpliSeq cancer hotspot panel V2.

Results

Mean age was 49.5 years with female predominance (77.6%). Histological types included 221 cases of adenocarcinoma not otherwise specified (NOS), 23 invasive papillary carcinoma, 11 mucinous adenocarcinoma, 8 adenosquamous, 1 signet ring, 3 neuroendocrine and 1 undifferentiated carcinoma. Majority (76.1%) presented with stage 3/4 disease. Overall positive expression of p53 was 44.8%, VEGF 79.4%, HER2/Neu 27.3% and EGFR 34.6%. Intratumoral heterogeneity was evident in HER2/Neu. Marker expression was not significantly associated with stage, grade, type and metastasis except VEGF which correlated with histological type (P=0.018) and tumor grade (P=0.027). NGS using Ion AmpliSeq cancer hotspot panel V2 revealed multiple non synonymous mutations, most frequent being TP53 and CDKN2A mutations and mutations in MET, KDR, PIK3CA, VHL, MPL, HER2 and SMARCB1 genes.

Conclusions

Predictive targetable markers like HER2/Neu, VEGF and EGFR are expressed in high proportion of gallbladder carcinoma. Significant expression of RAS pathway molecules suggests that interactions take place among the different members of the ErbB family during tumor development.

Multiple Functions of Long Non-Coding RNAs in Oxidative Stress, DNA Damage Response and Cancer Progression

In addition to aberrant alternation of transcriptome, it is now suggested that dysregulation of the non-coding transcripts, particularly long non-coding RNAs (lncRNAs), which comprise the majority of the genome, is contributed to cancer initiation and progression. As the result of recent huge efforts, the possible roles of numerous lncRNAs in the human cancers were characterized, as well as various strategies with inhibitory effects to target these transcripts on the transformed cells. Moreover, DNA damage response (DDR) pathway is a complex regulatory network responsible for the identification of disruptions in DNA structure, integrity and stability- it is reported to be associated with the up-regulation and down-regulation of lncRNAs. This review explores the involvement of the various lncRNAs in different human cancers, afterwards discusses the association of the lncRNAs expression with the DDR and oxidative stress, which are implicated in a myriad pathophysiological and physiological intra- and extracellular damages. J. Cell. Biochem. 119: 223-236, 2018. © 2017 Wiley Periodicals, Inc.

Gallbladder cancer epidemiology, pathogenesis and molecular genetics: Recent update

Gallbladder cancer is a malignancy of biliary tract which is infrequent in developed countries but common in some specific geographical regions of developing countries. Late diagnosis and deprived prognosis are major problems for treatment of gallbladder carcinoma. The dramatic associations of this orphan cancer with various genetic and environmental factors are responsible for its poorly defined pathogenesis. An understanding to the relationship between epidemiology, molecular genetics and pathogenesis of gallbladder cancer can add new insights to its undetermined pathophysiology. Present review article provides a recent update regarding epidemiology, pathogenesis, and molecular genetics of gallbladder cancer. We systematically reviewed published literature on gallbladder cancer from online search engine PubMed (http://www.ncbi.nlm.nih.gov/pubmed). Various keywords used for retrieval of articles were Gallbladder, cancer Epidemiology, molecular genetics and bullion operators like AND, OR, NOT. Cross references were manually searched from various online search engines (http://www.ncbi.nlm.nih.gov/pubmed,https://scholar.google.co.in/, http://www.medline.com/home.jsp). Most of the articles published from 1982 to 2015 in peer reviewed journals have been included in this review.

Targeting Angiogenesis in Biliary Tract Cancers: An Open Option

Biliary tract cancers (BTCs) are characterized by a bad prognosis and the armamentarium of drugs for their treatment is very poor. Although the inflammatory status of biliary tract represents the first step in the cancerogenesis, the microenvironment also plays a key role in the pathogenesis of BTCs, promoting tumor angiogenesis, invasion and metastasis. Several molecules, such as vascular endothelial growth factor (VEGF) and fibroblast growth factor (FGF), are involved in the angiogenesis process and their expression on tumor samples has been explored as prognostic marker in both cholangiocarcinoma and gallbladder cancer. Recent studies evaluated the genomic landscape of BTCs and evidenced that aberrations in several genes enrolled in the pro-angiogenic signaling, such as FGF receptor-2 (FGFR-2), are characteristic of BTCs. New drugs targeting the signaling pathways involved in angiogenesis have been tested in preclinical studies both in vitro and in vivo with promising results. Moreover, several clinical studies tested monoclonal antibodies against VEGF and tyrosine kinase inhibitors targeting the VEGF and the MEK/ERK pathways. Herein, we evaluate both the pathogenic mechanisms of BTCs focused on angiogenesis and the preclinical and clinical data available regarding the use of new anti-angiogenic drugs in these malignancies.

IL17 producing γδT cells induce angiogenesis and are associated with poor survival in gallbladder cancer patients

Despite conventional treatment modalities, gallbladder cancer (GBC) remains a highly lethal malignancy. Prognostic biomarkers and effective adjuvant immunotherapy for GBC are not available. In the recent past, immunotherapeutic approaches targeting tumor associated inflammation have gained importance but the mediators of inflammatory circuit remain unexplored in GBC patients. In the current prospective study, we investigated the role of IL17 producing TCRγδ(+) (Tγδ17), CD4(+) (Th17), CD8(+) (Tc17) and regulatory T cells (Tregs) in pathogenesis of GBC. Analysis by multi-color flow cytometry revealed that compared to healthy individuals (HI), Tγδ17, Th17 and Tc17 cells were increased in peripheral blood mononuclear cells (PBMCs) and tumor infiltrating lymphocytes (TIL) of GBC patients. Tregs were decreased in PBMCs but increased in TILs of GBC patients. The suppressive potential of Tregs from GBC patients and HI were comparable. Serum cytokines profile of GBC patients showed elevated levels of cytokines (IL6, IL23 and IL1β) required for polarization and/or stabilization of IL17 producing cells. We demonstrated that Tγδ17 cells migrate toward tumor bed using CXCL9-CXCR3 axis. IL17 secreted by Tγδ17 induced productions of vascular endothelial growth factor and other angiogenesis related factors in GBC cells. Tγδ17 cells promote vasculogenesis as studied by chick chorioallantoic membrane assay. Survival analysis showed that Tγδ17, Th17 and Treg cells in peripheral blood were associated with poor survival of GBC patients. Our findings suggest that Tγδ17 is a protumorigenic subtype of γδT cells which induces angiogenesis. Tγδ17 may be considered as a predictive biomarker in GBC thus opening avenues for targeted therapies.

Advances in biomarkers of biliary tract cancers

Tumor biomarkers can be applied for early diagnosis or precise treatment, thereby leading to personalized treatment and better outcomes. Biliary tract cancers (BTCs) are a group of cancers that occurs in different locations and have different clinical or genetic properties. Though the incidence of BTCs is rare, BTCs are among the most lethal cancers in the world and all have very low 5-year survivals. Lack of efficient early diagnostic approaches or adjuvant therapies for BTCs are main reasons. These urge us to broaden the researches into BTC biomarkers. Although few progresses of diagnostic biomarkers for BTCs have been achieved, there are still some advances in prognostic, predictive and therapeutic areas. In this review, we will focus on these achievements.

Prognostic implications of estrogen receptor 1 and vascular endothelial growth factor A expression in primary gallbladder carcinoma

AIM: To investigate the prognostic significance of estrogen receptor 1 (ER1) and vascular endothelial growth factor A (VEGF-A) expression in primary gallbladder carcinoma (GBC) to identify new prognostic markers for this malignancy.

METHODS: Using immunohistochemistry, we investigated ER1 and VEGF-A expression in 78 GBC and 78 cholelithiasis (CS) tissues. The results were correlated with clinicopathological features. Univariate and multivariate analyses were performed to evaluate the relationship between ER1 and VEGF-A expression and patients’ prognosis. Further Kaplan-Meier survival analysis was also performed.

RESULTS: ER1 and VEGF-A expression was significantly higher in GBC compared with CS (47/78 vs 28/78, P < 0.05; 51/78 vs 33/78, P < 0.05). ER1 expression was correlated with gender (P < 0.05) and VEGF-A expression was correlated with tumor differentiation in GBC patients (P < 0.05). In univariate analysis, age and tumor node metastasis (TNM) stage were factors associated with GBC prognosis (P < 0.05). Although there was no statistical difference between the expression of ER1 or VEGF-A and overall survival, the high expression of ER1 combined with VEGF-A predicted a poor prognosis for GBC patients (16.30 ± 1.87 vs 24.97 ± 2.09, log-rank P < 0.05). In multivariate analysis, combined expression of ER1 and VEGF-A and TNM stage were independent prognostic factors for GBC patients (P < 0.05).

CONCLUSION: Combined expression of ER1 and VEGF-A is a potential prognostic marker for GBC patients. Clinical detection of ER1 and VEGF-A in surgically resected GBC tissues would provide an important reference for decision-making of postoperative treatment programs.

Targeting specific molecular pathways holds promise for advanced gallbladder cancer therapy

Gallbladder cancer is the most common and aggressive malignancy of the biliary tract. The complete surgical resection is the only potentially curative approach in early stage; however, most cases are diagnosed in advanced stages and the response to traditional chemotherapy and radiotherapy is extremely limited, with modest impact in overall survival. The recent progress in understanding the molecular alterations of gallbladder cancer has shown great promise for the development of more effective treatment strategies. This has mainly resulted from the identification of molecular alterations in relevant intracellular signaling pathways-Hedgehog, PI3K/AKT/mTOR, Notch, ErbB, MAPK and angiogenesis-which are potential tailored targets for gallbladder cancer patients. This review discusses the recent remarkable progress in understanding the molecular alterations that represent novel prognosis molecular markers and therapeutic targets for gallbladder cancer, which will provide opportunities for research and for developing innovative strategies that may enhance the benefit of conventional chemotherapy, or eventually modify the fatal natural history of this orphan disease.

Identification of suitable reference genes for investigating gene expression in human gallbladder carcinoma using reverse transcription quantitative polymerase chain reaction

Reverse transcription quantitative polymerase chain reaction (RT‑qPCR) has become a frequently used strategy in gene expression studies. The relative quantification method is an important and commonly used method for the evaluation of RT‑qPCR data. The key aim of this method is to identify an applicable internal reference gene, however, there are currently no suitable reference genes for gene analysis in gallbladder carcinoma. In the present study, screening was performed using 12 common reference genes, which were selected in order to provide an experimental basis for the investigation of gene expression in gallbladder carcinoma. A total of 16 tissue samples of gallbladder carcinoma and their matched normal gallbladder tissues were used. The gene expression stability and applicability of the 12 reference gene candidates were determined using the geNorm, NormFinder and BestKeeper software programs. Following comparison of the results of the three software programs, HPRT1 was identified as the most stably expressed reference gene. In the normal gallbladder group, the relative stably expressed reference gene was PPIA and in the entire sample group, the relatively stably expressed reference gene was PPIA. The present study also demonstrated that the combination of the three reference genes was the most appropriate. The recommended combinations were PPIA + PUM1 + ACTB for the total sample group, GAPDH + PBGD + ALAS1 for the gallbladder carcinoma group and PPIA + PUM1 + TBP for the paired normal gallbladder group.

Potential therapeutic targets for the primary gallbladder carcinoma: estrogen receptors

Gallbladder carcinoma, the most frequent malignant neoplasm of the biliary tract system, has always been considered to feature late clinical presentation and diagnosis, limited treatment options and an extremely poor prognosis. In recent years, while the incidence of gallbladder cancer has appeared to be on the increase, the available treatment methods have not greatly improved survival of the affected patients. Thus, exploring new therapeutic targets for this devastating disease is an urgent matter at present. Epidemical studies have demonstrated that the incidence of gallbladder carcinoma exhibits a distinct gender bias, affecting females two to three times more than males, pointing to crucial roles of estrogen. It is well known that estrogen acts on target tissues by binding to estrogen receptors (ERs), which are mainly divided into three subtypes, ERα, ERβ and ERγ. ERα and ERβ appear to have overlapping but also unique even opposite biological effects. As important pathogenic mediators, ERs have been considered to relate to several kinds of tumors. In gallbladder carcinoma tissue, ERs have been shown to be positively expressed, and ERs expression levels are associated with differentiation and prognosis of this cancer. Nevertheless, the exact mechanisms of estrogen inducing growth of gallbladder carcinoma remain poorly understood. On the base of the current investigations, we deduce that estrogen participates in promotion of gallbladder carcinoma by influencing the formation of gallstones, stimulating angiogenesis, and promoting abnormal proliferation. Since ERs mediate the carcinogenic actions of estrogen in gallbladder, and therapy targeting ERs may provide new directions for gallbladder carcinoma. Therefore, it should be stressed that ERs are potential therapeutic targets for gallbladder carcinoma.

Adjuvant treatment in biliary tract cancer: To treat or not to treat?

Biliary tract cancer is a rare malignant tumor. There is limited knowledge about biology and natural history of this disease and considerable uncertainty remains regarding its optimal diagnostic and therapeutic management. The role of adjuvant therapy is object of debate and controversy. Although resection is identified as the most effective and the only potentially curative treatment, there is no consensus on the impact of adjuvant chemotherapy and/or radiotherapy on the high incidence of disease recurrence and on survival. This is mainly due to the rarity of this disease and the consequent difficulty in performing randomized trials. The only two prospectively controlled trials concluded that adjuvant chemotherapy did not improve survival. Most of the retrospective trials, which had limited sample size and included heterogeneous patients population and non-standardized therapies, suggested a marginal benefit of chemoradiotherapy in reducing locoregional recurrence and an uncertain impact on survival. Well-designed multi-institutional randomized trials are necessary to clarify the role of adjuvant therapy. Two ongoing phase III trials may provide relevant information.