Implications of the p53 tumor-suppressor gene in clinical oncology

Immunotherapy-based novel nanoparticles in the treatment of gastrointestinal cancer: Trends and challenges

Gastrointestinal cancer (GIC) is the most common cancer with a poor prognosis. Currently, surgery is the main treatment for GIC. However, the high rate of postoperative recurrence leads to a low five-year survival rate. In recent years, immunotherapy has received much attention. As the only immunotherapy drugs approved by the Food and Drug Administration (FDA), immune checkpoint blockade (ICB) drugs have great potential in cancer therapy. Nevertheless, the efficacy of ICB treatment is greatly limited by the low immunogenicity and immunosuppressive microenvironment of GIC. Therefore, the targets of immunotherapy have expanded from ICB to increasing tumor immunogenicity, increasing the recruitment and maturation of immune cells and reducing the proportion of inhibitory immune cells, such as M2-like macrophages, regulatory T cells and myeloid-derived suppressor cells. Moreover, with the development of nanotechnology, a variety of nanoparticles have been approved by the FDA for clinical therapy, so novel nanodrug delivery systems have become a research focus for anticancer therapy. In this review, we summarize recent advances in the application of immunotherapy-based nanoparticles in GICs, such as gastric cancer, hepatocellular carcinoma, colorectal cancer and pancreatic cancer, and described the existing challenges and future trends.

Role of Microbial Infection-Induced Inflammation in the Development of Gastrointestinal Cancers

There has been increasing evidence that a local inflammatory response stimulates tumor cells to acquire metastatic potential, and the concept of inflammatory oncotaxis has been spreading in recent years. However, the interaction between microbial inflammation and the development of gastrointestinal cancer is still unclear. This review summarizes the present knowledge on the role of microbial inflammation in the development of gastrointestinal cancers from the perspective of molecular biological findings. Chronic inflammation caused by bacterial infection is known to induce cancers as exemplified by Helicobacter pylori, which is associated with the development of gastric cancer via the activation of the TLR4 pathway by bacterial lipopolysaccharide followed by cancer growth through CagA-MET signaling. In addition, the development of inflammatory bowel diseases has been known to become a risk factor for colorectal cancers, where inflammation caused by certain bacterial infections plays a key role. It is also known that the cancer microenvironment is associated with cancer growth. Moreover, infectious complication after surgery for gastrointestinal cancers may promote tumor progression via the stimulation of pathogen-associated molecular patterns and various inflammatory mediators secreted by immunocytes. Further research on the link between microbial inflammation and cancer progression is needed to drive a paradigm shift in cancer treatment.

Advances in the Diagnosis and Management of Neonatal Sarcomas

Neonatal sarcomas comprise a heterogeneous group of rare soft tissue neoplasms that present unique diagnostic and therapeutic challenges. Recent advances in molecular profiling have improved diagnostic capabilities and reveal novel therapeutic targets. Clinical trials demonstrate differences in behavior between sarcoma subtypes that allow for better clinical management. Surgical resection has been replaced with a multimodal approach that includes chemotherapy and radiotherapy. Despite these advances, neonates with sarcoma continue to fare worse than histologically similar sarcomas in older children, likely reflecting differences in tumor biology and the complexities of neonatal medicine. This review focuses on recent advances in managing neonatal sarcomas.

Selective induced apoptosis and cell cycle arrest in MCF7 and LNCap cell lines by skin mucus from round goby (Neogobius melanostomus) and common carp (Cyprinus carpio) through P53 expression

The skin mucus in lower vertebrates such as fish with strong innate immune system has many unique and valuable bioactive compounds that can be used for inducing apoptosis in cancer cells. This study was looking for the cytotoxic potential of mucus from the two fish species, including round goby (Neogobius melanostomus) and common carp (Cyprinus carpio), and inducing apoptosis in MCF7 and LNCaP cancer cell lines via influencing P53 gene expression and cell cycle arrest. Results showed that the both mucus types have cytotoxic effects on the both cancer cell lines whereas they have no severe effect on normal primary fibroblast cells. In addition, round goby mucus and common carp mucus selectively induced apoptosis in the LNCaP and MCF7 cells, respectively, through up-regulating P53 gene and arresting cell cycle at the G1 phase. Taken together, this study suggested that the both mucus types can selectively influence P53 pathway and induce apoptosis in especial cancer cells. The skin mucus derived from round Goby and common Carp can be a promising candidate for investigation about apoptosis and molecular targeting therapy in cancer.

An update in the management of pediatric sarcoma

PURPOSE OF REVIEW

Nonrhabdomyosarcoma soft tissue sarcoma (NRSTS) is a rare subgroup of malignancy in childhood that is composed of a variety of soft tissue and bony tumors. Prognosis for resectable localized disease is usually good and improved with systemic treatment. However, survival from locally advanced and metastatic disease remains poor. There have been numerous preclinical and clinical studies to define histopathology, biology, and genetic alteration of sarcomas. The purpose of this review is to clarify the progress in the management of NRSTS.

RECENT FINDINGS

Genomic analysis, including the use of next-generation sequencing, has revealed fusion transcripts or specific genetic alterations which provide diagnostic biomarkers and potential targets for novel therapies.

SUMMARY

Most cases are sporadic, but some are associated with genetic predispositions. Most present as a painless mass and diagnosis is frequently delayed because of a low index of suspicion. There is a wide array of histopathological subtypes. Investigations usually involve core, incisional or excisional biopsy for tissue diagnosis, and cross-sectional and nuclear imaging for staging. Management of pediatric sarcoma is largely dependent on the patient's histopathological diagnosis, age, disease stage, and co-morbidities but usually involves a combination of systemic and local therapies. Preclinical studies and phase I/II trials of newer targeted therapies are ongoing.

Current status and new treatment approaches in TP53 mutated AML

Mutations in the essential tumor suppressor gene, TP53, are observed in only 5-10% of acute myeloid leukemia (AML) cases, but are highly associated with therapy-related AML and cases with complex karyotype. The mutational status of TP53 is a critical prognostic indicator, with dismal outcomes consistently observed across studies. Response rates to traditional cytotoxic chemotherapy are poor and long-term survival after allogeneic hematopoietic stem cell transplant is rare. Therapy with hypomethylating agents has resulted in a modest improvement in outcomes over intensive chemotherapy, but durable responses are seldom observed. In view of the intrinsic resistance to standard chemotherapies conferred by mutations in TP53, novel treatment approaches are required. In this review, we examine the current treatment landscape in TP53 mutated AML and discuss emerging therapeutic approaches currently under clinical investigation.

TP53 and therapy-related myeloid neoplasms

Therapy-related myeloid neoplasms (t-MNs) are the most serious late complications in patients treated with traditional cytotoxic chemotherapy and/or radiation. T-MNs are aggressive and chemorefractory hematologic malignancies, with a median survival of less than 6 months. TP53 mutations are highly enriched in t-MN patients, though the mechanism for this selective enrichment has only come to light over the past several years. In this review, we discuss the history and function of p53, and the role of TP53 mutations in the origin and progression of t-MNs. Emerging data has begun to elucidate who may be at highest risk of developing t-MNs, which ideally will enable us to develop preventative strategies for this devastating disease. As t-MNs may not be avoidable, novel therapies are urgently needed for this patient group and are underway as exemplified by recent investigation in restoring wild-type p53 function as well as directly targeting TP53 mutant variants. With better prevention and treatment, outcomes will hopefully begin to improve in the near future.

Extract of Rhus verniciflua Stokes Induces p53-Mediated Apoptosis in MCF-7 Breast Cancer Cells

Rhus verniciflua Stokes has long been used as a food supplement and traditional herbal medicine for various ailments in East Asia. We evaluated the anticancer effects of Rhus verniciflua Stokes extract (RVSE) on MCF-7 cells by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, flow cytometry, annexin V/7-AAD staining, and western blotting. In addition, the gallic acid content of RVSE was assayed using high-performance liquid chromatography. RVSE inhibited the growth of MCF-7 cells in a dose-dependent manner by inducing apoptosis in the sub-G1 phase. RVSE also significantly increased the number of apoptotic cells and increased the expression of p53 and p21 in a dose-dependent manner. Furthermore, RVSE treatment increased the Bax:Bcl-2 ratio and the levels of apoptosis-related factors, such as cleaved caspase-3 and -9 and PARP, in MCF-7 cells. Our findings suggest that the proapoptotic effect of RVSE on MCF-7 cells is mediated by p53, p21, and the intrinsic mitochondrial cascade. Thus, RVSE shows promise for the prevention and treatment of breast cancer.

HPV infection and p53 and p16 expression in esophageal cancer: are they prognostic factors?

Background

Esophageal squamous cell carcinoma (ESCC) is a highly lethal malignant tumor. Currently, Human papillomavirus (HPV) is suggested as a potential risk factor for esophageal cancer (EC) in addition to the classic risk factors, alcohol and tobacco, but this hypothesis still remains contradictory. We sought to investigate wether HPV and well-known biomarkers (p16 and p53) and patient-related factors that may have impact on survival of ESCC.

Methods

We conducted a prospective cohort study. By using multiplex PCR, we determined the prevalence of high risk HPV in ESCC, and evaluated the immunohistochemical expression of p16 and p53, molecular markers related to esophageal carcinogenesis in order to verify the potential influence of these variables in patients’s survival. Survival rates were estimated using Kaplan-Meier methods. A multivariate confirmatory model was performed using Cox proportional hazards regression.

Results

Twelve (13.8%) of 87 patients were HPV-DNA positive. Positive reactions of p16 and p53 were 10.7% and 68.6%, respectively. Kaplan-Meier analysis indicated that men (p = 0.025) had poor specific-cancer survival and a shorter progression-free survival (p = 0.050) as compared to women; III or IV clinical stage (p < 0.019) had poor specific-cancer survival and a shorter progression-free survival (p < 0.001) compared to I and II clinical stage; not submitted to surgery (<0.001) and not submitted to chemoradiotherapy (p = 0.039) had a poor specific-cancer survival, as well. The multivariate analysis showed that HPV, p16 and p53 status are not predictive parameters of progression-free and specific-cancer survival.

Conclusion

HPV infection and p53 and p16 expression are not prognostic factors in ESCC.

Papillomaviruses: a systematic review

In the last decades, a group of viruses has received great attention due to its relationship with cancer development and its wide distribution throughout the vertebrates: the papillomaviruses. In this article, we aim to review some of the most relevant reports concerning the use of bovines as an experimental model for studies related to papillomaviruses. Moreover, the obtained data contributes to the development of strategies against the clinical consequences of bovine papillomaviruses (BPV) that have led to drastic hazards to the herds. To overcome the problem, the vaccines that we have been developing involve recombinant DNA technology, aiming at prophylactic and therapeutic procedures. It is important to point out that these strategies can be used as models for innovative procedures against HPV, as this virus is the main causal agent of cervical cancer, the second most fatal cancer in women.

Non-rhabdomyosarcoma

Pediatric non-rhabdomyosarcoma soft tissue sarcomas (NRSTS) are a heterogeneous group encompassing more than 50 different histological diagnoses arising from primitive mesenchymal tissue. Together, they comprise about half the soft tissue sarcomas diagnosed in children and young adults. Despite each histologies relative rarity, their management schema is similar among the different NRSTS histologies. Surgical management is an important component of the multimodal treatment strategy of all these tumors. Resection with negative margins, while maintaining function, plays an important role as a primary treatment of these patients as well as diminishing the risks of local and distant recurrence.

Gene Therapy: Recent Advances and Applications in Dermatology

Background:

Gene therapy is an innovative and exciting new branch of medicine. Despite the fact that a human disease has yet to be cured using this therapeutic approach, numerous clinical trials are taking place around the world based on encouraging preclinical data.

Objective:

The aim of this review is to bring the reader up to date with this rapidly advancing field and to highlight the technical advances that must occur before gene therapy will become common practice in dermatology.

Methods:

The current level of gene delivery technology restricts the applications. The advantages and disadvantages of viral and nonviral gene delivery systems are discussed.

Results:

Considerable advances are being made in the areas of cancer immunotherapy and vaccines. Of particular importance to the treatment of skin diseases will be the isolation and ex vivo manipulation of epidermal stem cells, the development of skin-specific regulatory sequences for gene expression, and the formulation of gene delivery systems suitable for systemic administration.

Conclusions:

In general, skin and keratinocytes are considered to be good targets for gene transfer applications, and several diseases have been identified as potential candidates for treatment in the near future.

Immunohistochemical Expression of p53, MDM2, and p21Wafi Oncoproteins in Endometriomas But Not Adenomyosis

OBJECTIVE

p53, MDM2, and p21Waf1 are oncoproteins that regulate the cell cycle. The purpose of this study was to examine the distribution of p53, MDM2, and p21Waf1 oncoprotein expression in endometriomas and in adenomyosis.

METHODS

Tissue samples from 25 women with pathologically confirmed endometriomas and 31 women with pathologically confirmed adenomyosis were analyzed. Expression of p53, MDM2, and p21Waf1 oncoproteins was assessed by immunohistochemical nuclear staining.

RESULTS

p53, MDM2, and p21Waf1 expression were detected in 20%, 60%, and 80% of endometrioma tissue samples, respectively. All endometrioma tissue samples expressing p53 also tested positive for both MDM2 and p21Waf1. MDM2 expression was significantly higher in the proliferative than in the secretory phase of the cycle. In contrast, all 31 adenomyosis tissue samples were negative for p53, MDM2, and p21Waf1 expression.

CONCLUSION

The expression of p53, MDM2, and p21Waf1 suggests a role for these oncoproteins in the regulation of endometrioma cell growth, but not in adenomyosis.

Clinical implications of cytosine deletion of exon 5 of P53 gene in non small cell lung cancer patients

AIM

Lung cancer is considered to be the most common cancer in the world. In humans, about 50% or more cancers have a mutated tumor suppressor p53 gene thereby resulting in accumulation of p53 protein and losing its function to activate the target genes that regulate the cell cycle and apoptosis. Extensive research conducted in murine cancer models with activated p53, loss of p53, or p53 missense mutations have facilitated researchers to understand the role of this key protein. Our study was aimed to evaluate the frequency of cytosine deletion in nonsmall cell lung cancer (NSCLC) patients.

METHODS

One hundred NSCLC patients were genotyped for P53 (exon5, codon168) cytosine deletion leading to loss of its function and activate the target genes by allele-specific polymerase chain reaction. The P53 cytosine deletion was correlated with all the clinicopathological parameters of the patients.

RESULTS AND ANALYSIS

59% cases were carrying P53 cytosine deletion. Similarly, the significantly higher incidence of cytosine deletion was reported in current smokers (75%) in comparison to exsmoker and nonsmoker. Significantly higher frequency of cytosine deletion was reported in adenocarcinoma (68.08%) than squamous cell carcinoma (52.83%). Also, a significant difference was reported between p53 cytosine deletion and metastasis (64.28%). Further, the majority of the cases assessed for response carrying P53 cytosine deletion were found to show faster disease progression.

CONCLUSION

The data suggests that there is a significant association of the P53 exon 5 deletion of cytosine in codon 168 with metastasis and staging of the disease.

Diagnostic Implication and Clinical Relevance of Ancillary Techniques in Clinical Pathology Practice

Hematoxylin–eosin-stained slide preparation is one of the most durable techniques in medicine history, which has remained unchanged since implemented. It allows an accurate microscopic diagnosis of the vast majority of tissue samples. In many circumstances, this technique cannot answer all the questions posed at the initial diagnostic level. The pathologist has always been looking for additional ancillary techniques to answer pending questions. In our daily histopathology practice, we referred to those techniques as special stains, but nowadays, they are more than stains and are collectively called ancillary tests. They include a wide range of techniques starting from histochemical stains and ending in one or more advanced techniques, such as immunohistochemistry, immunofluorescence, molecular studies, cytogenetic studies, electron microscopy, flow cytometry, and polymerase chain reaction.

Predictable factors for lymph node metastasis in early gastric cancer analysis of clinicopathologic factors and biological markers

Predicting lymph node metastasis (LNM) accurately is very important to decide treatment strategies preoperatively. The aim of this study was to explore risk factors that predict the presence of LNM in early gastric cancer (EGC). A total of 230 patients with EGC who underwent curative gastrectomy with lymph adenectomy at Xinhua Hospital from January 2006 to July 2014 were retrospectively reviewed. We studied the relationship between clinicopathological factors, biological markers (p53, ki67, nm23, vascular endothelial growth factor (VEGF), epidermal growth factor receptor (EGFR), E-cadherin (E-cad), beta-catenin (b-catenin), glutathione S-transferase (GST), and topoisomerase II (Topo II)), and LNM of EGC patients by chi-square test and logistic regression analysis. Meta-analyses were further conducted to review the effects of the proteins (P53, ki67, E-cad, and b-catenin) on LNM in ECG patients. LNM was detected in 42 (18.3 %) of 230 patients. Incidences of LNM was distinct in different tumor size (p = 0.044), depth of submucosal invasion (p < 0.0001), and P53 overexpression (p = 0.004). Multivariate analysis further indentified that large tumor size (≥20 mm, odds ratio (OR) = 2.168, p = 0.041), submucosa (OR = 4.000, p = 0.0005), and P53 overexpression (OR = 3.010, p = 0.022) were independent risk factors of LNM in EGC patients. The meta-analysis revealed a significantly statistical association of P53, ki67, and b-catenin with an increased risk of LNM in EGC patients (P53, OR = 1.81, p = 0.017; ki67, OR = 2.53, p = 0.0003; b-catenin, OR = 0.53, p = 0.01). Tumor size (≥20 mm), the depth of invasion (submucosa), and P53 overexpression may be helpful predictors of LNM in EGC patients. Furthermore, the results of meta-analysis revealed that P53, ki67 overexpression, and abnormal expression of b-catenin may be associated with LNM in EGC. The results need further validation in single large studies.

Predictive Role of p53 Protein as a Single Marker or Associated with ki67 Antigen in Oral Leukoplakia: A Retrospective Longitudinal Study

Oral leukoplakia (OL) is the most common potentially malignant lesion of the oral cavity. Immunohistochemical analysis of p53 and Ki67 proteins is a simple and inexpensive method widely used in non-dysplastic OLs to reveal lesions predicted to develop oral cancer. The present longitudinal study evaluated the predictive role of p53 and Ki67 proteins alone or in combination in a group of OLs without dysplasia followed for many years. Seventy-seven OL patients referred to our Department between January 2006 and October 2013 underwent histochemical analysis of p53 and Ki67 expression. OLs were considered at high risk in the presence of either high p53 expression (>20%), or low/normal p53 expression associated with high Ki67 expression (Ki67/p53 ratio >3). Seven OLs evolved to OSCC during the follow-up period. Three cases had p53 overexpression, while four had a high Ki67/p53 ratio. Statistical significance was reached when samples with p53 overexpression were combined with samples with high Ki67/p53 ratio (Chi square 5.3; p<0.02). The combined immunohistochemical expression of p53 and Ki67 proteins could be a useful and simple molecular marker for early detection of non-dysplastic OLs at risk of developing oral cancer.

Molecular diagnosis of intrahepatic cholangiocarcinoma

Intrahepatic cholangiocarcinomas (iCCA) are primary intrahepatic malignancies originating from biliary epithelia. While both hepatocellular cancer and iCCA can present as mass lesions within the liver, these cancers are distinct in their morphology, etiology, pathology, natural history and response to therapy. There is a need for accurate and sensitive molecular markers for the diagnosis of iCCA. Recent advances in elucidating molecular and genetic characteristics of iCCA offer the potential of molecular-based diagnosis of iCCA. Specific genetic mutations of IDH1/2, BAP1, p53, and KRAS, FGFR gene fusions and alterations in microRNA have all been described in iCCA. Although there are no accurate serum or biliary biomarkers currently available for diagnosis of iCCA, several potential candidates have been identified. Knowledge of specific genetic or molecular abnormalities offers potential for individualized approaches for the treatment of patients with iCCA in the future.

TP53 and CDKN2a mutations in never-smoker oral tongue squamous cell carcinoma

OBJECTIVES/HYPOTHESIS

To determine the incidence and clinical significance of TP53 and CDKN2a somatic mutations in never smokers with oral tongue squamous cell carcinoma (OTSCC).

STUDY DESIGN

Case series.

METHODS

Fifty-one paraffin-embedded tumors from never smokers with OTSCC were obtained. p53 and p16 expression was determined by immunohistochemical (IHC) staining. Tumor DNA was amplified by polymerase chain reaction, and direct sequencing and mutation analysis was performed. Statistical relationships among p53 and p16 IHC findings, TP53 and CDKN2a mutation status, and clinicopathologic characteristics were determined. Univariate and multivariate Cox models for survival were performed.

RESULTS

Sixteen tumors (31.4%) showed strong expression of p53 by IHC. There was no correlation between p53 status and clinicopathologic variables or survival outcomes. TP53 mutations were seen in 10 tumors (19.6%). Patients with TP53 mutations had higher tumor-node-metastasis (TNM) stage (P=0.049), worse tumor differentiation (P=0.025), earlier recurrence (P=0.024), and more often died from their disease (P=0.043) than those without mutations. Five tumors (9.8%) showed p16 positivity by IHC. There was no correlation between p16 status and clinicopathologic variables or survival. CDKN2a mutations were seen in four tumors (7.8%). Patients with CDKN2a mutations had earlier recurrence (P=0.019) and more often died from their disease (P=0.010) than those without mutations. Kaplan-Meier curves show worse disease-free survival (P=0.0162, P=0.0025) and overall survival (P=0.0095, P=0.0001) for TP53 and CDKN2a mutations, respectively. Multivariate analysis demonstrated that TP53 and CDKN2a mutations were independent predictors of disease-free survival (P=0.038 and P=0.039, respectively).

CONCLUSIONS

TP53 and CDKN2a mutations in never-smoker OTSCC are associated with worse clinicopathologic characteristics and poorer survival outcomes.

LEVEL OF EVIDENCE

N/A.

Basal-like breast cancer: update on clinicopathologic, immunohistochemical, and molecular features

CONTEXT

Basal-like breast carcinoma (BLBC) is a distinct molecular subtype of breast carcinoma identified through gene expression profiling studies.

OBJECTIVE

To provide the clinical background, the histologic profile, and the immunohistochemical profile of these tumors and discuss the current knowledge of their molecular signature and their implications on targeted molecular therapy.

DATA SOURCES

Data were obtained from review of the pertinent peer-reviewed literature.

CONCLUSIONS

Basal-like breast carcinomas are aggressive tumors with poor prognosis. Lack of targeted therapy makes their treatment a challenging task. Traditional chemotherapy is still associated with a high risk of relapse and death in a high percentage of patients. Platinum-based chemotherapy has been considered as a candidate for the treatment of BLBCs owing to their BRCA1 phenotype. Approximately 22% of patients treated with single-agent cisplatin show pathologic complete response, which is a comparable rate to that seen with nonplatinum agents. Antiangiogenic agents have been promising, but their currently demonstrated limited response is considered disappointing. Additionally, epidermal growth factor receptor was not shown to be a helpful target for BLBC. A recent study has shown that BLBC appears to be especially sensitive to MEK inhibitors, making it a promising therapeutic possibility. The list of new targets is still evolving and the "magic" therapeutic target is yet to be discovered.

MYC, FBXW7 and TP53 copy number variation and expression in gastric cancer

BACKGROUND

MYC deregulation is a common event in gastric carcinogenesis, usually as a consequence of gene amplification, chromosomal translocations, or posttranslational mechanisms. FBXW7 is a p53-controlled tumor-suppressor that plays a role in the regulation of cell cycle exit and reentry via MYC degradation.

METHODS

We evaluated MYC, FBXW7, and TP53 copy number, mRNA levels, and protein expression in gastric cancer and paired non-neoplastic specimens from 33 patients and also in gastric adenocarcinoma cell lines. We also determined the invasion potential of the gastric cancer cell lines.

RESULTS

MYC amplification was observed in 51.5% of gastric tumor samples. Deletion of one copy of FBXW7 and TP53 was observed in 45.5% and 21.2% of gastric tumors, respectively. MYC mRNA expression was significantly higher in tumors than in non-neoplastic samples. FBXW7 and TP53 mRNA expression was markedly lower in tumors than in paired non-neoplastic specimens. Moreover, deregulated MYC and FBXW7 mRNA expression was associated with the presence of lymph node metastasis and tumor stage III-IV. Additionally, MYC immunostaining was more frequently observed in intestinal-type than diffuse-type gastric cancers and was associated with MYC mRNA expression. In vitro studies showed that increased MYC and reduced FBXW7 expression is associated with a more invasive phenotype in gastric cancer cell lines. This result encouraged us to investigate the activity of the gelatinases MMP-2 and MMP-9 in both cell lines. Both gelatinases are synthesized predominantly by stromal cells rather than cancer cells, and it has been proposed that both contribute to cancer progression. We observed a significant increase in MMP-9 activity in ACP02 compared with ACP03 cells. These results confirmed that ACP02 cells have greater invasion capability than ACP03 cells.

CONCLUSION

In conclusion, FBXW7 and MYC mRNA may play a role in aggressive biologic behavior of gastric cancer cells and may be a useful indicator of poor prognosis. Furthermore, MYC is a candidate target for new therapies against gastric cancer.

Immunohistochemical evaluation of p53 expression with different antibodies in malignant canine tumours with or without p53 gene mutation

Six monoclonal antibodies and a polyclonal antibody (CM1) were used to investigate the overexpression of p53 protein by immunohistochemistry (IHC) in six sarcomas and 21 mammary carcinomas from 27 dogs. IHC was compared with p53 gene mutation analysis performed on the same samples. Only the monoclonal PAb240, PAb421 and the CM1 antibodies were able to detect expression of canine p53 protein. CM1 was found to give the highest concordance (8/11) between positive expression of the p53 protein by IHC and the presence of a gene mutation. In the samples that were negative for p53 expression by IHC, but contained a p53 gene mutation according to DNA analysis, the mutation often affected the epitopes that could have been recognized by these antibodies. Only one out of 16 tumours without a p53 gene mutation had a weakly positive IHC result. These findings indicate that in these two types of canine tumours, IHC - particularly with CM1 - can detect many alterations in p53 expression owing to a gene mutation. False-positive results were very infrequent.

Role of human papillomaviruses in esophageal squamous cell carcinoma

Esophageal cancer (EC) is responsible for almost half a million deaths worldwide annually and has a multifactorial etiology, which may account for its geographical variation in incidence. In the last 30 years the potential of human papillomaviruses (HPV) as oncogenes or co-factors in the tumorigenic process of esophageal squamous cell carcinoma (ESCC) has been widely studied. While the etiology of HPV in cervical and certain other anogenital and aerodigestive cancers has been established, results regarding its role in EC have been largely inconclusive. A causal association can be evaluated only with a case-control study, where normal controls are compared to ESCC cases for the presence of HPV. We reviewed all studies investigating ESCC tissue for HPV DNA and identified 139 that met our inclusion criteria, of which only 22 were case-control studies. Our results support previous findings of higher levels of HPV detection in high-risk ESCC regions than in areas of low risk. In addition, we confirm that the role of HPV in ESCC remains unclear, despite an accumulation of studies on the subject. The variations in investigative technique, study design and sample types tested may account for the lack of consistency in results. There is a need for a meta-analysis of all case-control studies to date, and for large, well-designed case-control studies with adequate power to investigate the association. The potential benefits of prophylactic HPV vaccines could be evaluated if HPV is identified as an etiological factor in EC, highlighting the need for further research in this area.

Prognostic significance of p53 protein expression in early gastric cancer

Mutations of the p53 tumor suppressor gene have been associated with abnormalities in cell cycle regulation, DNA repair and synthesis, apoptosis, and it has been implicated in the prognosis of advanced gastric cancer. The aim of this study was to evaluate the occurrence of p53 gene mutation and its possible prognostic implications in early gastric cancer. In a retrospective study, we studied 80 patients with early gastric cancer treated surgically between 1982 and 2001. Mutation of p53 gene was investigated in surgical gastric specimens by immunohistochemistry, and results were analyzed in relation to gender, age, macroscopic appearance, size and location of tumor, presence of lymph nodes, Lauren's histological type, degree of differentiation, and the 5-year survival. The expression of p53 was more frequent among the intestinal type (p = 0.003), the differentiated (p = 0.007), and the macroscopically elevated tumors (p = 0.038). Nevertheless, the isolated expression of p53 was not associated with the 5-year survival, or with the frequency of lymph node involvement. The degree of differentiation was detected as an independent factor related to the outcome of patients (0.044). Significantly shorter survival time was found in p53-negative compared with p53-positive patients, when considering the degree of differentiation of tumors, as assessed by Cox regression analysis (0.049). The association of p53 with the intestinal type, the degree of differentiation and morphological characteristics, may reflect the involvement of chronic inflammatory process underlying early gastric cancer. In this population sample, the expression of p53 alone has no prognostic value for early gastric cancer. However, the significant difference in p53 expression between subgroups of degree of differentiation of tumors can influence post-operative outcome of patients and may be related to possible distinct etiopathogenic subtypes.

Autoantibodies to tumor-associated antigens in epithelial ovarian carcinoma

This review will focus on recent knowledge related to circulating autoantibodies (AAbs) to tumor-associated antigens (TAAs) in epithelial ovarian carcinoma. So far, the following TAAs have been identified to elicit circulating AAbs in epithelial ovarian carcinoma: p53, homeobox proteins (HOXA7, HOXB7), heat shock proteins (HSP-27, HSP-90), cathepsin D, cancer-testis antigens (NY-ESO-1/LAGE-1), MUC1, GIPC-1, IL-8, Ep-CAM, and S100A7. Since AAbs to TAAs have been identified in the circulation of patients with early-stage cancer, it has been speculated that the assessment of a panel of AAbs specific for epithelial ovarian carcinoma TAAs might hold great potential as a novel tool for early diagnosis of epithelial ovarian carcinoma.

Micropapillary component in colorectal carcinoma is associated with lymph node metastasis in T1 and T2 Stages and decreased survival time in TNM stages I and II

Colorectal carcinoma with a micropapillary component (MP) is an exceptionally aggressive variant, but has never been investigated in terms of survival analysis. Thirty colorectal carcinomas with a MP were identified from a series of 221 colorectal carcinomas. Carcinomas with and without a MP were compared in terms of histologic and immunohistochemical markers. Colorectal carcinoma with a MP seemed to have a lower differentiation status, increased tumor budding, more frequent lymphovascular and perineural invasion, more frequent lymph node metastasis, higher tumor node metastasis (TNM) stage, and less nuclear beta-catenin staining (P<0.05). Further analysis revealed that the presence of a MP predicted more frequent lymph node metastasis in T1 and T2 stages but not in T3 and T4 stages. Five-year survival rates for patients with a MP and those without were 50% and 73%, respectively. Furthermore, in TNM stages I and II, but not in TNM stages III and IV, a MP was an unfavorable prognostic variable. A MP was demonstrated to be an independent unfavorable prognostic indicator in TNM stages I and II by the multivariate Cox proportional hazard model. Colorectal carcinoma with a MP should be distinguished from colorectal carcinoma of conventional histologic type.

Protective effects of selenomethionine against ionizing radiation under the modulation of p53 tumor suppressor

Ionizing radiation (IR) therapy has been widely employed in the treatment of cancer. However, certain issues, including toxicity, have been raised in conjunction with IR therapy for cancer. Recently, selenomethionine (SeMet) as an antioxidant has been the subject of a great deal of attention for its chemopreventive effects. In this study, we found that DNA repair activity has been enhanced in response to SeMet against IR. In addition, our data showed that p53 functional activity was significantly reduced against IR in the cells expressing a mutant form of redox factor 1 (Ref-1) contrast with Ref-1 wild-type cells treated with SeMet, suggesting that p53 activation under the modulation of Ref-1 might play an important role in IR-treated cells in the presence of SeMet. Furthermore, IR-induced micronuclei numbers were also reduced after treatment with SeMet, strongly implicating protection by SeMet in genomic stability against IR-induced genotoxicity. From this study, we suggest that the p53-mediated protective mechanism of SeMet might provide clues for reducing side effects of IR therapy.

Biomolecular markers in cancer of the tongue

The incidence of tongue cancer is increasing worldwide, and its aggressiveness remains high regardless of treatment. Genetic changes and the expression of abnormal proteins have been frequently reported in the case of head and neck cancers, but the little information that has been published concerning tongue tumours is often contradictory. This review will concentrate on the immunohistochemical expression of biomolecular markers and their relationships with clinical behaviour and prognosis. Most of these proteins are associated with nodal stage, tumour progression and metastases, but there is still controversy concerning their impact on disease-free and overall survival, and treatment response. More extensive clinical studies are needed to identify the patterns of molecular alterations and the most reliable predictors in order to develop tailored anti-tumour strategies based on the targeting of hypoxia markers, vascular and lymphangiogenic factors, epidermal growth factor receptors, intracytoplasmatic signalling and apoptosis.

Cdc2 as prognostic marker in stage UICC II colon carcinomas

PURPOSE

Cyclin-dependent kinase 2 (cdc2) controls the G2-M checkpoint and, therefore, the entrance of cells into mitosis. It might play a crucial role during tumour progression in colon carcinomas (CCA). Thus, the prognostic value of cdc2 expression and connected markers relevant for proliferation and apoptosis has to be evaluated.

EXPERIMENTAL DESIGN

Punch biopsies from the tumour centre and the invasion front of 0.6mm diameter from 392 CCA stage UICC II-IV were integrated in 14 recipient paraffin blocks. After immunohistochemical staining for cdc2, p53, caspase 3 and ki-67, a present (+) and absent (-) scoring was performed in the tissue arrays. The logrank test was used to compare distant metastasis and cancer-related survival. Multivariate Cox regression analysis was done to identify independent prognostic factors for parameters with significant influence on cancer-related survival (CRS) and distant metastasis (DM).

RESULTS

The pT-category (p=0.007), nodal status (p<0.001), extramural venous infiltration (p<0.001) and lymphatic vessel invasion (p=0.003) were identified as independent histological parameters for CRS. Univariate analysis relating to stage UICC II-IV CCA showed caspase 3 in the tumour centre (p=0.047) to be a prognostic marker for CRS. In stage UICC II cdc2 (p=0.041) and caspase 3 in the invasion front (p=0.026) could be identified as independent prognostic factors for CRS and DM by multivariate analysis.

CONCLUSIONS

Cdc2 and caspase 3 could be identified as independent prognostic markers in stage UICC II CCA. They might be of value to select patients who should receive adjuvant treatment.

Killing of p53-deficient hepatoma cells by parvovirus H-1 and chemotherapeutics requires promyelocytic leukemia protein

AIM: To evaluate the synergistic targeting and killing of human hepatocellular carcinoma (HCC) cells lacking p53 by the oncolytic autonomous parvovirus (PV) H-1 and chemotherapeutic agents and its dependence on functional promyelocytic leukemia protein (PML).

METHODS: The role of p53 and PML in regulating cytotoxicity and gene transfer mediated by wild-type (wt) PV H-1 were explored in two pairs of isogenic human hepatoma cell lines with different p53 status. Furthermore, H-1 PV infection was combined with cytostatic drug treatment.

RESULTS: While the HCC cells with different p53 status studied were all susceptible to H-1 PV-induced apoptosis, the cytotoxicity of H-1 PV was more pronounced in p53-negative than in p53-positive cells. Apoptosis rates in p53-negative cell lines treated by genotoxic drugs were further enhanced by a treatment with H-1 PV. In flow cytometric analyses, H-1 PV infection resulted in a reduction of the mitochondrial transmembrane potential. In addition, H-1 PV cells showed a significant increase in PML expression. Knocking down PML expression resulted in a striking reduction of the level of H-1 PV infected tumor cell death.

CONCLUSION: H-1 PV is a suitable agent to circumvent the resistance of p53-negative HCC cells to genotoxic agents, and it enhances the apoptotic process which is dependent on functional PML. Thus, H-1 PV and its oncolytic vector derivatives may be considered as therapeutic options for HCC, particularly for p53-negative tumors.

Predictive Role of p53 Protein as a Single Marker or Associated to Ki67 Antigen in Oral Carcinogenesis

p53 over-expression has been proposed as a reliable marker associated to oral carcinogenesis, although only about 50% of oral carcinomas (OSCC) are associated with p53 over-expression and even p53-negative lesions can progress to OSCC. The aim of the study was to determine whether the combination of p53 over-expression and p53 low-expression associated with Ki67 over-expression (high Ki67/p53 ratio) could lead to a more sensitive parameter. Immunohistochemical expression of Ki67 and p53 was measured in 54 specimens from OSCC; 27 specimens from moderate/severe epithelial dysplasia; 32 specimens from oral leukoplakias without epithelial dysplasia, and 13 specimens with normal epithelium. p53 over-expression was found in 31 (53%) samples from OSCC, in 10 (37%) samples from severe dysplasias, and in 5 (15%) samples from non-dysplastic lesions, while the combination of high p53 values with high Ki67/p53 ratio was observed in 93% of OSCC, in 81% of dysplastic lesions, and in 50% of non-dysplastic lesions. This parameter may have a clinical implication to detect early lesions with an impairment of p53 pathway, and probably at risk of progress to OSCC.

The clinical importance of Ki-67, p16, p14, and p57 expression in patients with advanced ovarian carcinoma

The present study addressed the impact of p14, p16, p57, and Ki-67 in a large cohort of uniformly treated patients with stage III ovarian cancer in relation to other clinicopathologic variables and prognosis. We immunohistochemically studied 171 primary tumors from previously untreated patients with advanced ovarian carcinomas for expression of Ki-67, p16, p14, and p57. High protein levels of Ki-67 (>10% positive nuclei) were found in 144 cases (84%), p16 (>50% positive nuclei) in 53 cases (31%), p57 (>10% positive nuclei) in 41 cases (24%), and p14 (any positive nuclei) in 19 cases (11%). A correlation between high Ki-67 expression and presence of residual disease after primary surgery (P = 0.019), ascites (P = 0.006), higher International Federation of Gynecology and Obstetrics substage (P < 0.001), poor differentiation (P < 0.001), and higher Silverberg histopathologic grade (P < 0.0001) was seen. High expression of p16 correlated to poor differentiation (P = 0.033) and higher Silverberg histopathologic grade (P = 0.018). In univariate analysis, high expression of Ki-67 (P = 0.0001) and p16 (P = 0.005) was associated with poor survival. However, in multivariate analysis, only high expression of Ki-67 was significantly associated with shorter survival (P = 0.025). No correlations were seen between expression of p14 and p57 and clinicopathologic parameters. None of the factors studied was able to predict response to chemotherapy. Our results showed that Ki-67 represents an independent prognostic predictor in stage III ovarian cancer. We did not find p16, p14, and p57 to be useful as prognostic markers.

Vaccination with p53 peptide-pulsed dendritic cells is associated with disease stabilization in patients with p53 expressing advanced breast cancer; monitoring of serum YKL-40 and IL-6 as response biomarkers

p53 Mutations are found in up to 30% of breast cancers and peptides derived from over-expressed p53 protein are presented by class I HLA molecules and may act as tumor-associated epitopes in cancer vaccines. A dendritic cell (DC) based p53 targeting vaccine was analyzed in HLA-A2+ patients with progressive advanced breast cancer. DCs were loaded with 3 wild-type and 3 P2 anchor modified HLA-A2 binding p53 peptides. Patients received up to 10 sc vaccinations with 5 x 10(6) p53-peptide loaded DC with 1-2 weeks interval. Concomitantly, 6 MIU/m(2) interleukine-2 was administered sc. Results from a phase II trial including 26 patients with verified progressive breast cancer are presented. Seven patients discontinued treatment after only 2-3 vaccination weeks due to rapid disease progression or death. Nineteen patients were available for first evaluation after 6 vaccinations; 8/19 evaluable patients attained stable disease (SD) or minor regression while 11/19 patients had progressive disease (PD), indicating an effect of p53-specific immune therapy. This was supported by: (1) a positive correlation between p53 expression of tumor and observed SD, (2) therapy induced p53 specific T cells in 4/7 patients with SD but only in 2/9 patients with PD, and (3) significant response associated changes in serum YKL-40 and IL-6 levels identifying these biomarkers as possible candidates for monitoring of response in connection with DC based cancer immunotherapy. In conclusion, a significant fraction of breast cancer patients obtained SD during p53-targeting DC therapy. Data encourage initiation of a randomized trial in p53 positive patients evaluating the impact on progression free survival.

Addition of TAT protein transduction domain and GrpE to human p53 provides soluble fusion proteins that can be transduced into dendritic cells and elicit p53-specific T-cell responses in HLA-A*0201 transgenic mice

The protein p53 has been shown to be an efficient tumour antigen in both murine and human cancer vaccine studies and cancer vaccines targeting p53 based on major histocompatibility complex (MHC) class I binding p53-derived peptides that induce cytotoxic T lymphocytes (CTLs) without p53-specific CD4(+) T-cell help have been tested by several research groups including ours. To obtain such CD4(+) T-cell help and cover a broader repertoire of MHC haplotypes we have previously attempted to produce recombinant human p53 for vaccination purposes. However, attempts to refold a hexahis-tagged p53 protein in our laboratory were unsuccessful. Here, we show that fusion of an 11-amino-acid region of the human immunodeficiency virus TAT protein transduction domain (PTD) to human p53 increases the solubility of the otherwise insoluble p53 protein and this rTAT-p53 protein can be transduced into human monocyte-derived dendritic cells (DCs). The induction of a p53-specific HLA-A*0201 immune response was tested in HLA-A*0201/K(b) transgenic mice after immunization with rTAT-p53-transduced bone-marrow-derived DCs. In these mice, p53-specific CD4(+) and CD8(+) T-cell proliferation was observed and immunization resulted in the induction of HLA-A*0201-restricted CTLs specific for two human p53-derived HLA-A*0201-binding peptides, p53(65-73) and p53(149-157). Addition of GrpE to generate rTAT-GrpE-p53 led to a further increase in protein solubility and to a small increase in DC maturation but did not increase the observed p53-specific T-cell responses. The use of rTAT-p53 in ongoing clinical protocols should be applicable and offers advantages to current strategies omitting the use of HLA-typed patients.

Enhanced tumor cell kill by combined treatment with a small-molecule antagonist of mouse double minute 2 and adenoviruses encoding p53

Strategies to treat cancer by restoring p53 tumor suppressor functions are being actively investigated. These approaches range from expressing an exogenous p53 gene in p53 mutant cancers to antagonizing a p53 inhibitor in p53 wild-type (WT) cancer cells. In addition, exogenous p53 is used to strengthen the anticancer efficacy of oncolytic adenoviruses. Many cancers express high levels of the major negative regulator of p53, mouse double minute 2 (MDM2) protein. Recently, a novel class of highly potent and specific MDM2 antagonists, the Nutlins, was identified. We envisioned that Nutlins could protect both endogenous and exogenous p53 from MDM2-mediated inactivation. We therefore investigated treating human cancer cells with a combination of adenovirus-mediated p53 gene therapy and Nutlin. Combination treatment resulted in broadly effective cell kill of p53 WT and p53-negative cancer cells. Cytotoxicity was associated with profound cell cycle checkpoint activation and apoptosis induction. We also tested Nutlin in combination with oncolytic adenoviruses. Nutlin treatment accelerated viral progeny burst from oncolytic adenovirus-infected cancer cells and caused an estimated 10- to 1,000-fold augmented eradication of p53 WT cancer cells. These findings suggest that Nutlins are promising compounds to be combined with p53 gene therapy and oncolytic virotherapy for cancer.

Dendritic cell-based immunotherapy

Dendritic cells (DCs) play a crucial role in the induction of antigen-specific T-cell responses, and therefore their use for the active immunotherapy of malignancies has been studied with considerable interest. More than a decade has passed since the publication of the first clinical data of DC-based vaccines, and through this and subsequent studies, a number of important developmental insights have been gleaned. These include the ideal source and type of DCs, the discovery of novel antigens and methods of loading DCs, the role of DC maturation, and the most efficient route of immunization. The generation of immune responses against tumor antigens after DC immunization has been demonstrated, and favorable clinical responses have been reported in some patients; however, it is difficult to pool the results as a whole, and thus the body of data remains inconclusive, in part because of varying DC preparation and vaccination protocols, the use of different forms of antigens, and, most importantly, a lack of rigorous criteria for defining clinical responses. As such, the standardization of clinical and immunologic criteria utilized, as well as DC preparations employed, will allow for the comparison of results across multiple clinical studies and is required in order for future trials to measure the true value and role of this treatment modality. In addition, issues regarding the optimal dose and clinical setting for the application of DC vaccines remain to be resolved, and recent clinical studies have been designed to begin to address these questions.

A new cancer diagnostic system based on a CDK profiling technology

A series of molecular pathological investigations of the molecules that stimulate the cyclin dependent kinases (CDK1, 2, 4, and 6) have led to enormous accumulation of knowledge of the clinical significance of these molecules for cancer diagnosis. However, the molecules have yet to be applied to clinical cancer diagnosis, as there is no available technology for application of the knowledge in a clinical setting. We hypothesized that the direct measurement of CDK activities and expressions (CDK profiling) might produce clinically relevant values for the diagnosis. This study investigated the clinical relevance of CDK profiling in gastrointestinal carcinoma tissues by using originally developed expression and activity analysis methods. We have established novel methods and an apparatus for analyzing the expression and activities of the CDK molecules in lysate of tumor tissue in a clinical setting, and examined 30 surgically dissected gastrointestinal carcinomas and corresponding normal mucosal specimens. We demonstrate here that remarkably elevated CDK2 activity is evident in more than 70% of carcinoma tissues. Moreover, a G1-CDK activity profiling accurately mirrored the differences in proliferation between tumor and normal colonic tissues. Our results suggest that CDK profiling is a potent molecular-clinical approach to complement the conventional pathological diagnosis, and to further assist in the individualized medications.

Titration of serum p53 antibodies in patients with gastric cancer: a single-institute study of 40 patients

BACKGROUND

Alterations of the p53 tumor suppressor gene are the most commonly observed genetic abnormalities in many different types of human malignancies. The accumulation of mutant p53 often leads to the production of p53 antibody (p53-Ab) in the sera of patients with various cancers. To evaluate the clinical implications of serum p53-Abs in patients with gastric cancer, we compared p53-Abs with conventional tumor markers such as carcinoembryonic antigen (CEA) and carbohydrate antigen (CA)19-9.

METHODS

Serum samples were obtained preoperatively from 40 patients with histologically confirmed gastric adenocarcinoma, including 28 (70%) patients in stage Ia. The serum p53-Abs were assessed by enzyme-linked immunosorbent assay, using a new version of a highly specific, quantitative p53-Abs Kit (MESACUP Kit II).

RESULTS

p53-Abs were detected in 6 (15%) of 40 patients with gastric cancer, including 3 patients with early gastric cancer. Seven (17.5%) of the 40 patients were positive for CEA in serum. However, none of 7 patients with high CEA levels were positive for p53-Abs. No significant correlation of p53-Abs with patient age, sex, pathological parameters, tumor markers such as CEA and CA19-9, or poor survival (P = 0.116) was observed.

CONCLUSION

Although we employed the latest version of the p53-Abs Kit, the sensitivity of serum p53-Ab in gastric cancer patients was relatively low. No correlation was found between the presence of p53-Ab and the staging of cancer or survival. However, serum p53-Ab was detectable in patients with gastric cancer even in the early stages of disease. In addition, it may be independent of CEA and CA19-9.

p53 autoantibodies from patients with head and neck cancer recognise common epitopes on the polypeptide chain of p53

In the present study, we analysed p53 autoantibodies from patients with head and neck cancer by ELISA, by Western blot using C- and N-terminal fragments of p53 and with peptide libraries of p53. We found that 8.2% of the patients with head and neck cancer developed antibodies against p53. Using additional p53 autoantibody-positive sera from patients with head and neck cancer, we found that all of these sera recognised common epitopes, which were also recognised by well-known mouse monoclonal antibodies against p53. Common epitopes are located in regions on the polypeptide chain of p53, which are functionally important for the role of p53 in growth control. Thus, the knowledge of these epitopes might be useful for the development of new strategies for cancer therapy.