Heat shock protein 70 and HLA-DR molecules tissue expression. Prognostic implications in colorectal cancer

Deciphering the divergent transcriptomic landscapes of cervical cancer cells grown in 3D and 2D cell culture systems

Cervical cancer remains a significant health challenge for women worldwide, with a disproportionate impact on developing regions like sub-Saharan Africa. Taking advantage of recent advancements in developing suitable preclinical models to study cell proliferation, differentiation, and gene expression, we used RNA sequencing to compare the transcriptomic profiles of SiHa cervical cancer cells grown in 3D versus 2D culture systems. Pathway analysis of 3D cultures revealed upregulation of immune activation, angiogenesis, and tissue remodeling pathways. The high expression of cytokines, chemokines, matrix metalloproteinases, and immediate early genes, suggests that 3D cultures replicate the tumor microenvironment better than 2D monolayer cultures. HPV gene expression analysis further demonstrated higher expression levels of HPV16 E1, E2, E6, and E7 genes in 3D versus 2D cultures. Further, by using a set of linear models, we identified 79 significantly differentially expressed genes in 3D culture compared to 2D culture conditions, independent of HPV16 viral gene effects. We subsequently validated five of these genes at the protein level in both the SiHa cell line and a newly developed, patient-derived cervical cancer cell line. In addition, correlation analysis identified 26 human genes positively correlated with viral genes across 2D and 3D culture conditions. The top five 3D versus 2D differentially expressed and HPV-correlated genes were validated via qRT-PCR in our patient derived cell line. Altogether, these findings suggest that 3D cultures provide superior model systems to explore mechanisms of immune evasion, cancer progression and antiviral therapeutics.

Role of the ER-induced UPR pathway, apoptosis, and autophagy in colorectal cancer

When large amounts of misfolded or unfolded proteins accumulate in the endoplasmic reticulum (ER) in response to stress, a process called unfolded protein response (UPR) is activated. The disruption of this process leads to many diseases including diabetes, neurodegenerative diseases, and many cancers. In the process of UPR in response to stress and unfolded proteins, specific signaling pathways are induced in the endoplasmic reticulum and subsequently transmitted to the nucleus and cytoplasm, causing homeostasis and restoring the cell's normal condition with reducing protein translation and synthesis. The UPR response followed by stress enhancement balances cell survival with death, therefore in this condition cells decide either to survive or have the path of apoptosis ahead. However, in some cases, this balance is disturbed and the UPR pathway is chronically activated or not activated and the cell conditions lead to cancer. This study aimed to briefly investigate the association between ER stress, UPR, apoptosis, and autophagy in colorectal cancer (CRC). Moreover, in current study, we will try to demonstrate canonical ways and methods for the treatment of CRC cells with attenuated ER stress.

Tumor Microenvironment in Thymic Epithelial Tumors: A Narrative Review

The tumor microenvironment (TME) is a complex and constantly changing entity. The TME consists of stromal cells, fibroblasts, endothelial cells, and innate and adaptive immune cells. Cancer development and progression occurs through this interplay between the tumor and the adjacent stroma. Cancer cells are capable of modifying their microenvironment by secreting various message-carrying molecules, such as cytokines, chemokines, and other factors. This action causes a reprogramming of the neighboring cells, which are enabled to play a crucial role in tumor survival and progression. The study of TME has many clinical implications in terms of cancer therapeutics because many new drugs, such as antibodies, kinase inhibitors, and liposome formulations that can encapsulate anti-cancer drugs, can be developed. Although chemotherapy is considered the standard of treatment for advanced disease, recent research has brought to light immunotherapy as a possible systemic alternative. However, the complex structure and function of the thymus hinders its routine use in clinical practice. The aim of this review paper is to discuss the recent advances in the investigation of the unique characteristics of the TME of thymic epithelial tumors that could possibly lead to the development of novel promising therapies.

Heat Shock Proteins HSPA1 and HSP90AA1 Are Upregulated in Colorectal Polyps and Can Be Targeted in Cancer Cells by Anti-Inflammatory Oxicams with Arylpiperazine Pharmacophore and Benzoyl Moiety Substitutions at Thiazine Ring

Heat shock proteins HSPA1/Hsp70α and HSP90AA1/Hsp90α are crucial for cancer growth but their expression pattern in colorectal polyps or whether they can be modulated by oxicams is unknown. We quantified (RTqPCR) HSPA1 and HSP90AA1 expression in 50 polyp-normal pairs in relation to polyp malignancy potential and examined the effect of piroxicam, meloxicam and five novel analogues on HSPA1 and HSP90AA1 expression (mRNA/protein) in colorectal adenocarcinoma lines. HSPA1 and HSP90AA1 were upregulated in polyps by 3- and 2.9-fold. Expression ratios were higher in polyps with higher dysplasia grade and dominant villous growth pattern, mostly a result of diminished gene expression in normal tissue. Classic oxicams had negligible/non-significant effect on HSP expression. Their most effective analogue inhibited HSPA1 protein and gene by 2.5-fold and 5.7-fold in Caco-2 and by 11.5-fold and 6.8-fold in HCT116 and HSPA1 protein in HT-29 by 1.9-fold. It downregulated HSP90AA1 protein and gene by 1.9-fold and 3.7-fold in Caco-2 and by 2-fold and 5.0-fold in HCT116. HSPA1 and HSP90AA1 are upregulated in colorectal polyps reflecting their potential for malignancy. HSPA1 in cancer cells and, to lesser degree, HSP90AA1 can be reduced by oxicam analogues with thiazine ring substituted via propylene linker by arylpiperazine pharmacophore with fluorine substituents and by benzoyl moiety.

Comprehensive Analysis of Regulatory Network for LINC00472 in Clear Cell Renal Cell Carcinoma

Renal cell carcinoma (RCC) accounts for about 2% to 3% of adult malignancies, and clear cell renal cell carcinoma (ccRCC) is the most common and aggressive type of kidney cancer. It accounts for 75% of all kidney tumors. Although new targeted drugs continue to appear, they are still not suitable for all patients. Therefore, an in-depth study of the molecular mechanism of the development of ccRCC and exploration of new targets for the treatment of ccRCC will help to achieve precise treatment for ccRCC. With the development of molecular research, the study of long noncoding RNA (LncRNA) has given us a new understanding of tumors. Although LncRNA does not encode proteins, it directly interacts with proteins in various signaling pathways and affects cell functions. Therefore, it is of great significance to study the mechanism of LncRNA in ccRCC. The expression level of Linc00472 in ccRCC tissues is significantly lower than adjacent normal tissues, and its low expression is closely related to Furman's high grade. The low expression of Linc00472 is associated with poor prognosis in patients with ccRCC. The results of protein interaction and functional enrichment analysis indicate that genes upregulated in renal clear cell carcinoma may play a major role. Analysis of target gene prediction results showed that Linc00472 may be used as ceRNA in the miR-24-3p-HLA-DPB1 pathway, miR-24-3p-CXCL9 pathway, miR-221-3p-C3aR1-VEGFR2 pathway, miR-17-5p-HLA-DQA1/HLA-DQB1 pathway, and miR-17-5p-C3aR1/C5aR1-VEGFR2 pathway which play important functions. In addition, the regulatory relationship between miR-24-3p and TNFR2 (TNFRSF1B), CD36, and COL4A1 should also be noted. The value of Linc00472 in the diagnosis and treatment of ccRCC is worthy of further study.

The Prognostic Significance of Hsp70 in Patients with Colorectal Cancer Patients: A PRISMA-Compliant Meta-Analysis

Background

Hsp70 (heat shock protein 70) plays a key role in carcinogenesis and cancer progression. However, the relationship between the Hsp70 expression level and the colorectal cancer patient survival is unknown. This study is aimed at investigating the relationship between Hsp70 and the prognosis of colorectal carcinoma patients.

Methods

PubMed, Web of Science, and Embase were used for systematic computer literature retrieval. Stata SE14.0 software was used for quantitative meta-analysis. Besides, data was extracted from selected articles. Relationships between Hsp70 expression level and prognosis were further studied. The hazard ratios (HRs) and 95% confidence intervals (95% CIs) were also computed.

Results

A total of 11 potentially eligible studies with 2269 patients were identified in 10 tumors from PubMed, Web of Science, and Embase. Hsp70 overexpression was associated with poor overall survival (OS) and disease-free survival (DFS) in colorectal carcinoma patients (HRs, 0.65 (95% CI: 0.52-0.78) and 0.77 (95% CI: 0.23-1.32), respectively).

Conclusions

Hsp70 overexpression can predict poor survival in colorectal cancer patients.

Expressions of HLA Class II Genes in Cutaneous Melanoma Were Associated with Clinical Outcome: Bioinformatics Approaches and Systematic Analysis of Public Microarray and RNA-Seq Datasets

Major histocompatibility complex (MHC) class II molecules, encoded by human leukocyte antigen (HLA) class II genes, play important roles in antigen presentation and initiation of immune responses. However, the correlation between HLA class II gene expression level and patient survival and disease progression in cutaneous melanoma is still under investigation. In the present study, we analyzed microarray and RNA-Seq data of cutaneous melanoma from The Cancer Genome Atlas (TCGA) using different bioinformatics tools. Survival analysis revealed higher expression level of HLA class II genes in cutaneous melanoma, especially HLA-DP and -DR, was significantly associated with better overall survival. Furthermore, the expressions of HLA class II genes were most closely associated with survival in cutaneous melanoma as compared with other cancer types. The expression of HLA class II co-expressed genes, which were found to associate with antigen processing, immune response, and inflammatory response, was also positively associated with overall survival in cutaneous melanoma. Therefore, the results indicated that increased HLA class II expression may contribute to enhanced anti-tumor immunity and related inflammatory response via presenting tumor antigens to the immune system. The expression pattern of HLA class II genes may serve as a prognostic biomarker and therapeutic targets in cutaneous melanoma.

HSP47 is associated with the prognosis of laryngeal squamous cell carcinoma by inhibiting cell viability and invasion and promoting apoptosis

Heat shock protein 47 (HSP47) is a 47 kDa collagen binding protein that has a close relationship with the development and progression of tumours. However, little is known concerning the expression profile of HSP47 in laryngeal squamous cell carcinoma (LSCC) patients and there is still insufficient data concerning the underlying mechanisms. The aim of the present study was to explore the expression of HSP47 in LSCC and provide an overview of its association with tumourigenicity and clinical prognosis. The expression of HSP47 in LSCC and adjacent non-cancerous laryngeal tissues was assessed via western blotting and immunohistochemical studies. The prognostic significance of HSP47 expression was analysed using a Kaplan-Meier survival curve. To investigate the influence of HSP47 on the viability, invasion and apoptosis of a LSCC cell line, we performed an in vitro analysis with plasmid vectors and small interfering RNA (siRNA). Our results showed that HSP47 protein expression in the LSCC tissues was markedly decreased compared to that noted in the adjacent non-cancerous tissues, and low expression of HSP47 was correlated with poor prognosis in LSCC patients. Upregulation of HSP47 via plasmid vectors inhibited the proliferation, reduced the invasive ability, increased the sensitivity to cisplatin chemotherapy, promoted apoptosis, and induced the G1 phase arrest of LSCC cells in vitro. The expression of apoptosis-regulating proteins was also altered when HSP47 was upregulated, involving increased expression of cleaved caspase-7/-8/-9, PARP, and Bax and decreased expression of Bcl-2. Our present data suggest that HSP47 is an important prognostic factor and an attractive therapeutic target in LSCC due to its influence on the biological behaviour of LSCC cells.

HLA class II antigen-processing pathway in tumors: Molecular defects and clinical relevance

The human leukocyte antigen (HLA) class II antigen-processing machinery (APM) presents to cognate CD4⁺ T-cells antigenic peptides mainly generated from exogeneous proteins in the endocytic compartment. These CD4⁺ T cells exert helper function, but may also act as effector cells, thereby recognizing HLA class II antigen-expressing tumor cells. Thus, HLA class II antigen expression by tumor cells influences the tumor antigen (TA)-specific immune responses and, depending on the cancer type, the clinical course of the disease. Many types of human cancers express HLA class II antigens, although with marked differences in their frequency. Some types of cancer lack HLA class II antigen expression, which could be due to structural defects or deregulation affecting different components of the complex HLA class II APM and/or from lack of cytokine(s) in the tumor microenvironment. In this review, we have summarized the information about HLA class II antigen distribution in normal tissues, the structural organization of the HLA class II APM, their expression and regulation in malignant cells, the defects, which have been identified in malignant cells, and their functional and clinical relevance.

The cytomegalovirus protein UL138 induces apoptosis of gastric cancer cells by binding to heat shock protein 70

It has been hypothesized that human cytomegalovirus (HCMV) could act as a tumor promoter and play an “oncomodulatory” role in the neoplastic process of several human malignancies. However, we demonstrate for the first time that UL138, a HCMV latency-associated gene, could act as a tumor inhibitor in gastric cancer (GC). The expression of UL138 is down-regulated in HCMV positive gastric adenocarcinoma tissues, especially in poorly or none differentiated tumors. Overexpression of UL138 in several human GC cell lines inhibits cell viability and induces apoptosis, in association with the reduction of an anti-apoptotic Bcl-2 protein and the induction of cleaved caspase-3 and caspase-9. Moreover, protein array analysis reveals that UL138 interacts with a chaperone protein, heat shock protein 70 (HSP70). This interaction is confirmed by immunoprecipitation and immunostaining in situ in GC cell lines. In addition, this UL138-mediated cancer cell death could efficiently lead to suppression of human tumor growth in a xenograft animal model of GC. In conclusion, these results uncover a previously unknown role of the cytomegalovirus protein UL138 in inducing GC cells apoptosis, which might imply a general mechanism that viral proteins inhibit cancer growth in interactions with both chaperones and apoptosis-related proteins. Our findings might provide a potential target for new therapeutic strategies of GC treatment.

Hsp70 exerts oncogenic activity in the Apc mutant Min mouse model

Colorectal cancer (CRC) develops from colonic epithelial cells that lose expression of key tumor suppressor genes and/or gain expression of proproliferative and antiapoptotic genes like heat shock protein 70 (Hsp70). Heat shock protein 70 is overexpressed in CRC, but it is not known whether this is in response to the proteotoxic stress induced by transformation, or if it contributes to the process of transformation itself. Here, using the Apc (Min/+) mouse model of CRC, we show that Hsp70 regulates mitogenic signaling in intestinal epithelial cells through stabilization of proteins involved in the receptor tyrosine kinase (RTK) and WNT signaling pathways. Loss of Hsp70 reduced tumor size with decreased proliferation and increased tumor cell death. Hsp70 loss also led to decreased expression of ErbB2, Akt, ERK and β-catenin along with decreased β-catenin transcriptional activity as measured by c-myc and axin2 expression. Upregulation of RTK or WNT signals are frequent oncogenic events in CRC and many other cancers. Thus, in addition to the role of Hsp70 in cell-survival after transformation, Hsp70 stabilization of β-catenin, Akt, ERK and ErbB2 are predicted to contribute to transformation. This has important implications not only for understanding the pathophysiology of these cancers, but also for treatment since anti-EGFR antibodies are in clinical use for CRC and EGFR is a major ErbB2 heterodimeric partner. Targeting Hsp70, therefore, might provide an alternative or complementary strategy for achieving better outcomes for CRC and other related cancer types.

HSP27 and 70 expression in thymic epithelial tumors and benign thymic alterations: diagnostic, prognostic and physiologic implications

Thymic Epithelial Tumors (TETs), the most common tumors in the anterior mediastinum in adults, show a unique association with autoimmune Myasthenia Gravis (MG) and represent a multidisciplinary diagnostic and therapeutic challenge. Neither risk factors nor established biomarkers for TETs exist. Predictive and diagnostic markers are urgently needed. Heat shock proteins (HSPs) are upregulated in several malignancies promoting tumor cell survival and metastases. We performed immunohistochemical staining of HSP27 and 70 in patients with TETs (n = 101) and patients with benign thymic alterations (n = 24). Further, serum HSP27 and 70 concentrations were determined in patients with TETs (n = 46), patients with benign thymic alterations (n = 33) and volunteers (n = 49) by using ELISA. HSPs were differentially expressed in histologic types and pathological tumor stages of TETs. Weak HSP tumor expression correlated with worse freedom from recurrence. Serum HSP concentrations were elevated in TETs and MG, correlated with clinical tumor stage and histologic subtype and decreased significantly after complete tumor resection. To conclude, we found HSP expression in the vast majority of TETs, in physiologic thymus and staining intensities in patients with TETs have been associated with prognosis. However, although interesting and promising the role of HSPs in TETs as diagnostic and prognostic or even therapeutic markers need to be further evaluated.

Variations in the MHC region confer risk to esophageal squamous cell carcinoma on the subjects from high-incidence area in northern China

Background

The human major histocompatibility complex (MHC) is the most important region in vertebrate genome, and is crucial in innate immunity. Recent studies have demonstrated the possible role of polymorphisms in the MHC region to high risk for esophageal squamous cell carcinoma (ESCC). Our previous genome-wide association study (GWAS) has indicated that the MHC region may confer important risk loci for ESCC, but without further fine mapping. The aim of this study is to further identify the risk loci in the MHC region for ESCC in Chinese population.

Methods

Conditional logistic regression analysis (CLRA) was performed on 24 single nucleotide polymorphisms (SNPs) within the MHC region, which were obtained from the genetically matched 937 cases and 692 controls of Chinese Han population. The identified promising SNPs were further correlated with clinical and clinicopathology characteristics. Immunohistochemistry was performed to explore the protein expression pattern of the related genes in ESCC and neighboring normal tissues.

Results

Of the 24 promising SNPs analyzed, we identified three independent SNPs in the MHC region associated with ESCC: rs35399661 (P = 6.07E-06, OR = 1.71, 95%CI = 1.36–2.17), rs3763338 (P = 1.62E-05, OR = 0.63, 95%CI = 0.50–0.78) and rs2844695 (P = 7.60E-05, OR = 0.74, 95%CI = 0.64–0.86). These three SNPs were located at the genes of HLA-DQA1, TRIM27, and DPCR1, respectively. Further analyses showed that rs2844695 was preferentially associated with younger ESCC cases (P = 0.009). The positive immunostaining rates both for HLA-DQA1 and TRIM27 were much higher in ESCC tissues than in neighboring normal tissues (69.4% vs. 26.8% for HLA-DQA1 and 77.6% vs. 47.8% for TRIM27, P<0.001). Furthermore, the overexpression of HLA-DQA1 is correlated significantly with age (P = 0.001) and family history (P<0.001).

Conclusion

This study for the first time provides evidence that multiple genetic factors within the MHC region confer risk to ESCC on the subjects from high-risk area in northern China.

Heat shock protein 70 (HSP70) expression is associated with poor prognosis in intestinal type gastric cancer

Heat shock protein 70 (HSP70) is a molecular chaperone which plays an important role in cellular protection against various stressful stimuli and in the regulation of cellular growth and apoptosis. This study was conducted in gastric carcinoma (GC) to assess correlations of HSP70 expression with clinicopathological parameters and overall survival (OS). Tissue microarray blocks were constructed from 172 GCs and immunohistochemically stained for HSP70. Low HSP70 expression was found in 122 GCs (71 %), whereas 50 (29 %) had high expression. HSP70 expression was higher in tumours in the cardia (p = 0.008), with non-signet ring cell histology (p < 0.001), of intestinal type (p = 0.045) and of higher pathological T stage (p = 0.026). When considering the cohort as a whole, HSP70 expression did not correlate with OS (p = 0.092). In intestinal type carcinomas, however, high HSP70 expression significantly correlated with worse OS (p = 0.034). These results suggest that HSP70 expression might be an unfavourable prognostic factor in patients with GC, especially of intestinal type.

Prognostic significance of heat shock protein 70 expression in early gastric carcinoma

Background

Overexpression of heat shock protein 70 (HSP70) has been observed in many types of cancer including gastric adenocarcinomas, although the exact role of HSP70 in carcinogenesis remains unclear.

Methods

The study analyzed a total of 458 radical gastrectomy specimens which were immunohistochemically stained with HSP70, p53, and Ki-67 antibodies.

Results

The study determined that the expression of HSP70 was significantly increased in early gastric cancer (EGC) compared to advanced gastric cancer (p<0.001). The HSP70 expression was correlated with well-differentiated tumor type, intestinal type of Lauren classification and the lower pT and pN stage. Negative expression of Ki-67 and p53 expression was associated with poor prognosis. The study did not find any correlation between HSP70 and p53 expression. The study determined that HSP70 expression in the EGC subgroup was associated with a poor prognosis (p=0.009), as well as negative Ki-67 expression (p=0.006), but was not associated with p53. Based on multivariate analysis, HSP70 expression (p=0.024), negative expression of Ki-67, invasion depth and lymph node metastasis were determined to be independent prognostic markers.

Conclusions

HSP70 is expressed in the early stages of gastric adenocarcinoma. In EGC, HSP70 is a poor independent prognostic marker and is correlated with a low proliferation index.

Comparative proteomic study for profiling differentially expressed proteins between Chinese left- and right-sided colon cancers

The aim of the present study is to profile differentially expressed protein markers between left-sided colon cancer (LSCC) and right-sided colon cancer (RSCC). Fresh tumor tissue samples from LSCC (n = 7) and RSCC (n = 7) groups were analyzed by two-dimensional electrophoresis coupled with MALDI-TOF-MS, followed by Western blotting. In 50 paraffin embedded samples from each group, levels of four differentially expressed proteins (identified by proteomics analysis) were measured by tissue microarray with immunohistochemistry staining to compare the different protein markers between LSCC and RSCC. Sixteen proteins were found to be differentially expressed between LSCC and RSCC. Ten proteins including HSP-60 and PDIA1 were identified to be highly expressed in LSCC (P < 0.01 or P < 0.05), while the expression of six proteins including EEF1D and HSP-27 were higher in RSCC (P < 0.01 or P < 0.05). Virtually all of the indentified proteins were involved in cellular energy metabolism, protein folding/unfolding, and/or oxidative stress. Human colon tumors at various locations have different proteomic biomarkers. Differentially expressed proteins associated with energy metabolism, protein folding/unfolding and oxidative stress contribute to different tumorigenesis, tumor progression, and prognosis between left- and right-sided colon cancer.

Improving colorectal cancer management: the potential of proteomics

Colorectal cancer (CRC) is the third most common cancer worldwide. Successful treatment is heavily dependent on tumor stage at the time of detection, but unfortunately CRC is often only detected in advanced stages. New biomarkers in the form of genes or proteins that can be used for diagnosis, prognostication, follow-up, and treatment selection and monitoring could be of great benefit for the management of CRC. Furthermore, proteins could prove valuable new targets for therapy. Therefore, clinical proteomics has gained a lot of scientific interest in this regard. To get an overall insight into the extent to which this research has contributed to a better management of CRC, we give a comprehensive overview of the results of proteomics research on CRC, focusing on expression proteomics, in other words, protein profiling studies. Furthermore, we evaluate the potential of the discriminating proteins identified in this research for clinical use as biomarkers for (early) diagnosis, prognosis and follow-up of CRC or as targets for new therapeutic regimens.

HSP27 expression in primary colorectal cancers is dependent on mutation of KRAS and PI3K/AKT activation status and is independent of TP53

Colorectal adenomas display features of senescence, but these are often lost upon progression to carcinoma, indicating that oncogene induced senescence (OIS) could be a roadblock in colorectal cancer (CRC) development. Heat shock proteins (HSPs) have been implicated in the prognosis of CRC and HSP based therapy is a current interest for drug development. Recent cell culture studies have suggested that in the absence of a TP53 mutation, OIS mediated by PI3K/AKT activation can be circumvented by high expression of HSPs. Furthermore, while PI3K/AKT activation and KRAS mutations are independent inducers of OIS, PI3K/AKT activation can suppress KRAS-induced OIS when both are present in cultured cells. As KRAS mutations, PI3K/AKT activation and TP53 mutations are all common features of CRC, it is possible that the requirement for HSP to inhibit OIS in CRC is dependent on the mutation spectrum of a tumour. However, work on HSP that utilised mutation profiled human tumour tissues has been limited. Here, we characterised the expression of two major HSP proteins (HSP27 and 72) by immunohistochemistry (IHC), the mutation status of TP53, KRAS and PIK3CA genes by direct sequencing and the activation status of AKT by IHC in a cohort of unselected primary CRC (n=74). We compare our data with findings generated from cell-based studies. Expression of HSP27 and HSP72 was correlated to clinicopathological and survival data but no significant association was found. We also established the mutation status of TP53, KRAS and PIK3CA genes and the activation status of AKT in our CRC panel. We did not detect any associations between HSP27 or HSP72 expression with TP53 mutation status. However, HSP27 expression in CRCs was strongly associated with the co-presence of wildtype KRAS and activated PI3K/AKT (p=0.004), indicating a possible role of HSP27 in overcoming PI3K/AKT induced OIS in tumours. Our studies suggest a role for using archival tissues in validating hypotheses generated from cell culture based investigations.

Combined hyperthermia and radiotherapy for the treatment of cancer

Radiotherapy is used to treat approximately 50% of all cancer patients, with varying success. Radiation therapy has become an integral part of modern treatment strategies for many types of cancer in recent decades, but is associated with a risk of long-term adverse effects. Of these side effects, cardiac complications are particularly relevant since they not only adversely affect quality of life but can also be potentially life-threatening. The dose of ionizing radiation that can be given to the tumor is determined by the sensitivity of the surrounding normal tissues. Strategies to improve radiotherapy therefore aim to increase the effect on the tumor or to decrease the effects on normal tissues, which must be achieved without sensitizing the normal tissues in the first approach and without protecting the tumor in the second approach. Hyperthermia is a potent sensitizer of cell killing by ionizing radiation (IR), which can be attributed to the fact that heat is a pleiotropic damaging agent, affecting multiple cell components to varying degrees by altering protein structures, thus influencing the DNA damage response. Hyperthermia induces heat shock protein 70 (Hsp70; HSPA1A) synthesis and enhances telomerase activity. HSPA1A expression is associated with radioresistance. Inactivation of HSPA1A and telomerase increases residual DNA DSBs post IR exposure, which correlates with increased cell killing, supporting the role of HSPA1A and telomerase in IR-induced DNA damage repair. Thus, hyperthermia influences several molecular parameters involved in sensitizing tumor cells to radiation and can enhance the potential of targeted radiotherapy. Therapy-inducible vectors are useful for conditional expression of therapeutic genes in gene therapy, which is based on the control of gene expression by conventional treatment modalities. The understanding of the molecular response of cells and tissues to ionizing radiation has lead to a new appreciation of the exploitable genetic alterations in tumors and the development of treatments combining pharmacological interventions with ionizing radiation that more specifically target either tumor or normal tissue, leading to improvements in efficacy.

Proteomic analysis of advanced colorectal cancer by laser capture microdissection and two-dimensional difference gel electrophoresis

The emergence of laser capture microdissection (LCM) and two-dimensional difference gel electrophoresis (2D-DIGE) has been shown to greatly improve the accuracy and sensitivity of global protein expression analysis. However, their combined use in profiling tumour proteome has rarely been reported. In this study, we applied these techniques to profile the protein expression changes of the late stage colorectal cancer (CRC) and its liver metastases. The study revealed that both the primary and secondary tumours showed a distinct protein expression profile compared to normal tissues, but were indistinguishable from each other. Differential analysis between the primary tumour and patient-matched normal colon mucosa identified a total of 71 proteins to be altered in CRC. Over 40% of these proteins have been previously reported as CRC-related proteins, validating the accuracy of the current analysis. We have also identified many previously unknown changes including overexpression of ACY1, HSC70, HnRNP I, HnRNP A3, SET, ANP32A and TUFM in CRC, which have been further verified by western blotting and immunohistochemistry. This study demonstrated that LCM in combination with 2D-DIGE is a powerful tool to analyse the proteome of tumour tissues and may lead to the identification of potential novel protein markers and therapeutic targets for cancer.

Prognostic significance of heat shock protein 70 (HSP70) in patients with oral cancer

Backround

Oral squamous cell carcinoma (OSCC) is characterized by an aggressive growth pattern, local invasiveness, and spread to cervical lymph nodes. Overall survival rates have not improved, primarily due to locoregional tumor recurrences and distant metastasis. To date, no trustworthy or clinically applicable marker of tumor aggressiveness has been identified for OSCC. Heat shock proteins (HSPs) play a role in tumor antigenicity. This study aimed to investigate the expression and prognostic significance of highly stress-inducible HSP70 in OSCC.

Methods

Immunohistochemical staining for HSP70 was performed on surgical specimens obtained from 61 patients with OSCC. Light microscopy and analysis 3.1^® (Soft Imaging System, Münster, Germany), an image processing and analysis program, were used for evaluating HSP70 expression. The tumor region was defined as the region of interest (ROI) and HSP70-positive staining was analyzed.

Results

Immunoreactivity for HSP70 was positive in tumor cells of 38 of all patients (63.3%). Positive immunoreactivity of tumor cells could be detected in 17 of 28 patients with T2 tumors (60.7%) Prognostic significance of HSP70 expression in tumor cells was detected in patients with T2 tumors (p = 0.009).

Conclusions

The survival of patients suffering from T2 tumors with positive HSP70 expression was 8 times higher than that for patients with negative HSP70 expression, suggesting that T1-T2 tumors of OSCC with low expression of HSP70 require more radical treatment.

HLA-DR expression is associated with better prognosis in sporadic Australian clinicopathological Stage C colorectal cancers

Predicting patient outcome for colorectal carcinoma (CRC) with lymph node but not distant metastases remains challenging. Various prognostic markers have been identified including microsatellite instability (MSI) and possibly expression of the MHC Class II protein, HLA-DR. About 15% of sporadic CRC exhibits MSI associated with methylation of the DNA mismatch repair gene hMLH1 promoter. In addition, a significant proportion of unselected CRC demonstrates expression of HLA-DR. We sought to examine the relationship between HLA-DR expression, MSI status and prognosis in sporadic Australian Clinicopathological (ACP) Stage C CRC. Two hundred seventy consecutive patients with sporadic ACP Stage C CRC were treated at Concord Repatriation General Hospital between 1986 and 1992. None of these patients received adjuvant chemotherapy and all were followed for a minimum of 5 years or until death. DNA was extracted from paraffin sections and MSI status determined by PCR. HLA-DR expression was determined immunohistochemically using an antibody against the HLA-DR alpha chain. MSI status could be assigned in 235 cases: 176 CRCs (74.9%) were microsatellite stable, whereas 23 (9.8%) had high levels of MSI (MSI-H) and 36 (15.3%) had low levels of MSI (MSI-L). HLA-DR expression by CRC cells was seen in 148 (60.1%) cases and correlated with the presence of tumor-infiltrating lymphocytes (p = 0.0005) and peritumoral lymphocytes (p = 0.003), but not other clinicopathological features or MSI status. HLA-DR-positive CRCs were strongly associated with better patient outcome (p < 0.0001).

Inhibition of heat shock induction of heat shock protein 70 and enhancement of heat shock protein 27 phosphorylation by quercetin derivatives

Inhibitors of heat-induced heat shock protein 70 (HSP70) expression have the potential to enhance the therapeutic effectiveness of heat-induced radiosensitization of tumors. Among known small molecule inhibitors, quercetin has the advantage of being easily modified for structure-activity studies. Herein, we report the ability of five monomethyl and five carbomethoxymethyl derivatives of quercetin to inhibit heat-induced HSP70 expression and enhance HSP27 phosphorylation in human cells. While quercetin and several derivatives inhibit HSP70 induction and enhance HSP27 phosphorylation at Ser78, other analogues selectively inhibit HSP70 induction without enhancing HSP27 phosphorylation that would otherwise aid in cell survival. We also show that good inhibitors of HSP70 induction are also good inhibitors of both CK2 and CamKII, kinases that are known to activate HSP70 expression by phosphorylation of heat shock transcription factor 1. Derivatives that show poor inhibition of either or both kinases are not good inhibitors of HSP70 induction, suggesting that quercetin's effectiveness is due to its ability to inhibit both kinases.

GRP-induced up-regulation of Hsp72 promotes CD16+/94+ natural killer cell binding to colon cancer cells causing tumor cell cytolysis

Gastrin-releasing peptide (GRP) and its receptor (GRPR) are not normally expressed by epithelial cells lining the adult human colon. However post malignant transformation both GRP and its receptor are aberrantly expressed in the colon where we have previously shown they act to retard metastasis by enhancing tumor cell attachment to the extracellular matrix. In the present study, we show that GRP signaling via its cognate receptor when both are aberrantly expressed in human colon cancer cells causes heat shock protein 72 (Hsp72) to be expressed. We show that GRP/GRPR induces expression of Hsp72 by signaling via focal adhesion kinase. When expressed, Hsp72 promotes the binding of CD16+ and CD94+ natural killer cells, resulting in tumor cell cytolysis. These findings demonstrate the presence of a novel mechanism whereby aberrantly expressed GRP/GRPR in human colorectal cancer attenuates tumor progression and may promote a favorable outcome.

TRAIL-induced apoptosis is enhanced by heat shock protein 70 expression

Heat shock protein 70 (Hsp70) is a well-known inhibitor of apoptotic pathways; however, a role for Hsp70 in the modulation of death receptor-mediated apoptosis remains largely unexplored. In this study, the ability of Hsp70 to modulate tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL)-induced apoptosis was examined in SW480 and CCRF-CEM cells. These lines exhibit the characteristics of type I cells (SW480, human colon adenocarcinoma), with no requirement for mitochondrial involvement to exhibit apoptosis following death receptor engagement and type II cells (CCRF-CEM, human leukemic T cell), which do require amplification of the signal through the mitochondria. Unexpectedly, expression of Hsp70 in the type II CCRF-CEM cells enhanced the extent of TRAIL-induced apoptosis, but in SW480, Hsp70 had no impact on TRAIL-induced apoptosis. The enhanced TRAIL-induced apoptosis was accompanied by an up-regulation of TRAIL receptors, R1 and R2, at the cell surface as determined by flow cytometry and at the transcriptional level as assessed by real-time polymerase chain reaction (PCR). Increased expression of Hsp70 led to up-regulated expression of p53, and chromatin immunoprecipitation combined with real-time PCR revealed increased binding of p53 to its consensus sequence in the TRAIL-R2 gene. In contrast, expression of Hsp70 in SW480 cells did not increase p53 or TRAIL-R1 or TRAIL-R2 surface expression. This result is in marked contrast to most apoptotic stresses, including TNFalpha and Fas ligand, where Hsp70 has been shown to inhibit apoptosis in type II cells. These findings suggest that in tumors retaining functional p53 and expressing high levels of Hsp70, TRAIL may be an effective therapy.

Serum heat shock protein 70 levels and lung cancer risk: a case-control study nested in a large cohort study

Chronic inflammation contributes to the process of carcinogenesis, but few epidemiologic studies have examined associations with risk of lung cancer. Relationships between lung cancer risk and serum levels of both heat shock protein 70 (Hsp70) and high-sensitivity C-reactive protein (hsCRP) were investigated in a case-control study nested in the Japan Collaborative Cohort Study for Evaluation of Cancer Risk. Serum samples and lifestyle information were collected at baseline from 39,242 men and women between 1988 and 1990. Of these, 240 deaths from lung cancer were identified through 1999, and 569 controls were matched for sex, age, and study area. Serum levels were measured in 189 cases and 377 controls for Hsp70 and in 209 cases and 425 controls for hsCRP. Odds ratios (95% confidence intervals) across quartiles, adjusted for confounding factors, including smoking habits, were 0.83 (0.44-1.58), 1.41 (0.77-2.60), and 1.84 (0.92-3.71) for Hsp70 (P(trend) = 0.042) and 1.13 (0.67-1.91), 0.66 (0.38-1.16), and 1.19 (0.70-2.02) for hsCRP (P(trend) = 0.941). In males, odds ratios (95% confidence intervals) across quartiles were 1.30 (0.59-2.84), 1.74 (0.83-3.67), and 2.49 (1.06-5.85) for Hsp70 (P(trend) = 0.029). High levels of serum Hsp70 might thus be associated with increased risk of lung cancer among Japanese males, although further studies are needed to clarify associations between chronic inflammation and lung cancer.

Hypoxia, angiogenesis and apoptosis markers in locally advanced rectal cancer

BACKGROUND AND AIMS

Hypoxia-inducible factor 1alpha (HIF-1alpha) is a critical regulatory protein of cellular response to hypoxia. HIF-1alpha triggers the angiogenic process through activation of the vascular endothelial factor (VEGF) gene. The bcl-2 anti-apoptotic and the death promoting p53 genes, regulate the apoptotic cell death. We investigated the relationship between hypoxia, angiogenesis and apoptosis and their prognostic impact in patients with advanced rectal cancer.

PATIENTS AND METHODS

The immunohistochemical expression of HIF-1alpha, VEGF, p53 and bcl-2 and the determination of microvessel density (MVD), apoptotic index (AI) were carried out in tumour tissue samples obtained from 92 patients with locally advanced rectal cancer (LARC) (T3,4/N+/-).

RESULTS

HIF-1alpha high reactivity and VEGF overexpression were noted in 47.8 and 44.6% of the examined cases, respectively. They significantly correlated with lymph node metastasis (P<0.001) and low rectal location (P=0.016). HIF-1alpha expression was directly correlated with VEGF up-regulation (P<0.001) and MVD (P<0.001). VEGF expression was closely interrelated with MVD (P<0.001). In univariate analysis advanced grade, infiltrative pattern of tumour growth, vascular invasion, positive lymph node status, HIF-1alpha expression and VEGF upregulation were related to decreased disease-free and overall survival. In multivariate analysis, only high HIF-1alpha reactivity and positive lymph node status emerged as independent variables of adverse prognostic significance.

CONCLUSION

HIF-1alpha and VEGF may play an important predictive and prognostic role in patients with LARC.

Loss of human leucocyte antigen class I and gain of class II expression are early events in carcinogenesis: clues from a study of Barrett's oesophagus

BACKGROUND

Human leucocyte antigen (HLA) expression is altered in oesophageal carcinomas compared with normal tissue. It is unclear, however, whether this phenotype precedes malignant transformation or results as a consequence of it.

AIM

To investigate HLA class I and II expression in Barrett's oesophagus and normal squamous oesophageal tissue.

METHODS

Asian patients with Barrett's oesophagus (n = 64) and a control group (n = 60) with a normal oesophagus but without reflux symptoms were recruited using endoscopic and histopathological criteria. Tissue samples were stained with monoclonal antibodies specific for HLA-ABC, HLA-DR alpha chain or HLA-DP/DQ/DR, and scored semiquantitatively. The results of immunohistochemical staining were correlated with clinical and histopathological characteristics of patients.

RESULTS

Marked expression of HLA-ABC was observed in 50% of Barrett's oesophagus sections as compared with 68.3% of controls (p = 0.038). HLA-DR staining was seen in 51.6% of Barrett's oesophagus samples versus 11.7% of controls (p<0.001). Expression of HLA-DP/DQ/DR was evident in 73.4% of oesophageal intestinal metaplasia tissue as opposed to 18.3% of controls (p<0.001). Importantly, a total loss of HLA-ABC and a concomitant gain of HLA-DP/DQ/DR expression were seen in 37.5% of patients with Barrett's oesophagus but in none of the controls (p<0.001). Interestingly, this phenotype was associated positively with dysplasia (adjusted p, p* = 0.031) but negatively with non-steroidal anti-inflammatory drug use (p* = 0.004).

CONCLUSIONS

HLA class I expression is down regulated and class II expression is up regulated in Barrett's oesophagus. As these changes predate malignant transformation, altered major histocompatibility complex expression may be a key event in disease progression, possibly in facilitating evasion from immune surveillance.

Immunogenic hsp-70 is overexpressed in colorectal cancers with high-degree microsatellite instability

PURPOSE

Colorectal cancers that display high-degree mi-crosatellite instability are associated with an improved prognosis and evidence of an activated host immune response. Molecular analyses have suggested that heat shock proteins, a family of proteins that have key immunologic functions, are upregulated in these cancers. We aimed to explore the expression of heat shock proteins 70 and 110 and their relationship to microsatellite instability, survival, and other clinicopathologic parameters.

METHODS

Twenty-six colorectal cancers that displayed microsatellite instability were matched by age, stage, and site in the colorectum to 26 microsatellite-stable cancers. Immunohistochemistry was used to detect expression of both markers.

RESULTS

The microsatellite-unstable group showed significantly higher expression of heat shock protein 70 than the microsatellite-stable group (P = 0.006), and patients undergoing curative resections for unstable cancers had improved prognosis compared with their stable counterparts (P = 0.026). Significantly, in a multivariate survival analysis, low or absent heat shock protein 70 expression was independently associated with a poor outcome (P = 0.001).

CONCLUSIONS

Heat shock protein 70 has known functions that promote antitumor immune responses. Its overexpression in colorectal cancers with microsatellite instability may be pivotal to explaining these tumors' enhanced immunogenicity and improved prognosis.

Evaluation of ST13 gene expression in colorectal cancer patients

We identified a novel gene ST13 from a subtractive cDNA library of normal intestinal mucosa in 1993, more studies showed that ST13 was a co-chaperone of Hsp70s. Recently we detected the ST13 gene expression in tumor tissue and adjacent normal tissue of the same colorectal cancer patient and investigated if the ST13 gene expression might have any prognostic value. Analysis was performed at molecular level by reverse transcription-PCR using real-time detection method. We measured two genes simultaneously, ST13 as the target gene and glyceraldehydes-3-phosphate dehydrogenase as a reference gene, in primary colorectal tumor specimens and tumor-adjacent normal mucosa specimens from 50 colorectal cancer patients. The expression levels of the ST13 gene were significantly decreased in primary tumors compared with adjacent mucosa (P<0.05). But there were no significant differences in the expression of ST13 as compared with different Dukes' stage, tumor differentiation grade, invasion depth, lymph node metastasis and disease-specific survival.

Expression of heat shock protein 70 and 27 in non-small cell lung cancer and its clinical significance

The heat shock proteins (HSPs) 70 and HSP 27 expression in patients with non-small cell lung cancer (NSCLC) was studied and the relationship between HSP 70 and HSP 27 with the clinicopathological features of NSCLC was investigated. The expression of HSP 70 and HSP 27 was detected in tumor tissues from 60 patients with NSCLC by S-P immunohistochemistry. The findings were analyzed in combination with the histological types, histopathological differentiation, lymph node metastasis, patients' clinical stages, smoking history and gender. The results showed that of the 60 NSCLC tissue specimens studied, the immunoreactivity of HSP 70 and HSP 27 was detected in 47 (78.3%) and 43 (71.7%) specimens, respectively. A positive correlation was found between the overexpression of HSP 70 and HSP 27. The histopathological differentiation, lymph node metastasis, clinical stages and smoking history were correlated to the expression of HSP 70, but not to the expression of HSP 27. No statistical significance was observed in histological types and gender with respect to both HSP 70 and HSP 27 expression. It is suggested that the HSP 70 expression is a powerful and significant prognostic indicator and is related to histopathological differentiation, lymph node metastasis, patients' clinical stages, smoking history, whereas HSP 27 expression is not.

Hsp72 Inhibits Fas-mediated Apoptosis Upstream of the Mitochondria in Type II Cells

Heat shock protein 72 (Hsp72) inhibits apoptosis induced by some stresses that trigger the intrinsic apoptosis pathway. However, with the exception of TNFalpha-induced apoptosis, a role for Hsp72 in modulating the extrinsic pathway of apoptosis has not been clearly established. In this study, it was demonstrated that Hsp72 could inhibit Fas-mediated apoptosis of type II CCRF-CEM cells, but not type I SW480 or CH1 cells. Similar results were obtained when Fas ligand or an agonistic Fas antibody initiated the Fas apoptosis pathway. In CCRF-CEM cells, Hsp72 inhibited mitochondrial membrane depolarization and cytochrome c release but did not alter surface Fas expression or processing of caspase-8 and Bid, indicating that Hsp72 acts upstream of the mitochondria to inhibit Fas-mediated apoptosis. Thus, the ability of Hsp72 to inhibit Fas-mediated apoptosis is limited to type II cells where involvement of the intrinsic pathway is required for efficient effector caspase activation.

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Inducible Hsp70 as target of anticancer immunotherapy: Identification of HLA-A*0201-restricted epitopes

The design of a broad application tumor vaccine requires the identification of tumor antigens expressed in a majority of tumors of various origins. We questioned whether the major stress-inducible heat shock protein Hsp70 (also known as Hsp72), a protein frequently overexpressed in human tumors of various histological origins, but not in most physiological normal tissues, constitutes a tumor antigen. We selected the p391 and p393 peptides from the sequence of the human inducible Hsp70 that had a high affinity for HLA-A*0201. These peptides were able to trigger a CTL response in vivo in HLA-A*0201-transgenic HHD mice and in vitro in HLA-A*0201+ healthy donors. p391- and p393-specific human and murine CTL recognized human tumor cells overexpressing Hsp70 in a HLA-A*0201-restricted manner. Tetramer analysis of TILs showed that these Hsp70 epitopes are targets of an immune response in many HLA-A*0201+ breast cancer patients. Hsp70 is a tumor antigen and the Hsp70-derived peptides p391 and p393 could be used to raise a cytotoxic response against tumors of various origins.

Expression of heat shock protein (Hsp) 70 and Hsp 40 in colorectal cancer

Heat shock protein (Hsp) 70 and Hsp 40 are stress proteins that cooperate as chaperones in mammalian cells. The present study was designed to determine the expression levels of Hsp 70 and Hsp 40 in colorectal cancer by immunohistochemistry and Western blot analysis. Among 50 colorectal cancer tissues studied, 80% and 14% of tumors showed specific immunoreactivity to Hsp 70 and Hsp 40, respectively. Hsp 70 and Hsp 40 were overexpressed in cancer tissue samples compared with normal tissues, on both analytic sets. However, there were no significant correlations between their expression and various clinicopathological parameters of colorectal cancer. Hsp 70 and Hsp 40 may be tumor markers for colorectal cancer.

Targeted therapy of solid malignancies via HLA class II antigens: a new biotherapeutic approach?

Intracellular signals, delivered in professional antigen-presenting cells following the engagement of major histocompatibility complex (MHC) class II molecules, activate a variety of cellular functions that also contribute to efficient antigen presentation. As far as human malignancies, the signaling ability of human leukocyte antigens (HLA) class II molecules is a rather well-characterized event in hematologic tumors; in contrast, very limited evidences are available in solid neoplasias of different histotypes that may constitutively express HLA class II antigens. Among solid malignancies, a significant proportion of human cutaneous melanomas have been shown to express HLA class II molecules, and cutaneous melanoma undoubtedly represents a 'model disease' to investigate tumor immunobiology, to unveil the molecular basis underlying the interactions between neoplastic cells and host's immune system, and ultimately to set up new bio-immunotherapeutic approaches. Upcoming preclinical evidences unveil a signaling potential of HLA-DR antigens expressed on melanoma cells, and suggest for the clinical implication of HLA class II molecules as novel therapeutic targets. Therefore, in this review, we will focus on the emerging role of HLA class II antigens as intracellular signal transducing elements in neoplastic cells of the melanocytic lineage, emphasizing their foreseeable role in targeted therapy of human melanoma and potentially of HLA class II antigens-positive tumors of different histology.

Expression of heat shock protein (Hsp) 70 and Hsp 40 in gastric cancer

Heat shock proteins (Hsp) 70 and Hsp 40 are stress proteins that cooperate as chaperones in mammalian cells. We determined the expression of Hsp 70 and Hsp 40 in 81 gastric cancers. Immunoreactivities to Hsp 70 and Hsp 40 were detected in 67.9 and 22.2% of tumors, respectively. Immunohistochemical analysis showed enhanced Hsp 70 and Hsp 40 expression in gastric tumor tissue, relative to the surrounding normal tissue. Overexpression of Hsp 70 and Hsp 40 was also confirmed by immunoblotting. Among various clinicopathological parameters, low histopathological differentiation was associated with reduced expression of both proteins.

Expression profiling in multistage hepatocarcinogenesis: identification of HSP70 as a molecular marker of early hepatocellular carcinoma

Hepatocellular carcinoma (HCC) associated with chronic liver disease evolves from precancerous lesions and early HCC to a progressed form. Nodule-in-nodule-type HCC (progressed HCC within early HCC) represents the transition from early to progressed HCC and, therefore, is useful in molecular genetic analysis of HCC progression during multistage carcinogenesis. We compared expression profiles among 7 early components and 7 progressed components of nodule-in-nodule-type HCCs and their corresponding noncancerous liver tissues with oligonucleotide array. Of the approximately 12,600 genes that were analyzed, a set of 95 genes provided a molecular signature that distinguished between early HCC components and their noncancerous liver tissues, and a set of 92 genes distinguished between progressed and early HCC components. Of these genes, the most abundantly up-regulated gene in early HCC components (P <.001) was heat-shock protein 70 (HSP70). Real-time quantitative reverse transcription polymerase chain reaction (RT-PCR) confirmed this finding. Further immunohistochemical examination of HSP70 revealed its significant overexpression in early HCC compared with precancerous lesions (P <.001) and in progressed HCC compared with early HCC (P <.001). In conclusion, molecular signatures were clearly different in noncancerous liver tissue as compared with the early and progressed components of nodule-in-nodule-type HCC. Moreover, HSP70 could be a sensitive marker for the differential diagnosis of early HCC from precancerous lesion or noncancerous liver, a difficult distinction for pathologists due to very well differentiated histology with little atypia in early HCC.

Strong HLA-DR expression in microsatellite stable carcinomas of the large bowel is associated with good prognosis

Progression of colorectal cancer may follow either of two main genetic routes: the chromosome- or microsatellite-instability pathways. Association between the patients' prognosis and microsatellite instability has been questioned. Improved survival has previously been found in patients with expression of HLA-DR antigens on their tumour cells. In this study, the expression of HLA-DR antigen was investigated by immunohistochemistry in 357 large bowel carcinomas stratified by microsatellite instability status. Sixteen per cent of the tumours showed strong HLA-DR expression and 35% had weak DR expression. We confirmed that patients with strong positive HLA-DR staining had improved survival (P<0.001) compared to patients with no HLA-DR expression. Strong epithelial HLA-DR staining was significantly associated with high level of microsatellite instability (P<0.001). In the subgroup of tumours with characteristics typical of the chromosomal instability phenotype, i.e. in microsatellite-stable tumours, the patients positive for the HLA-DR determinants showed better survival than those without HLA-DR expression. The protective effect of HLA-DR expression on survival was confirmed by multivariate analysis, both in the whole patient group and in the microsatellite-stable/microsatellite instability-low group. This might be explained by enhanced T-cell mediated anti-tumour immune responses against tumour cells in the HLA-DR positive tumours. The finding of better patient survival in the subgroup of strong HLA-DR positive microsatellite-stable tumours may have clinical implications for these patients.

p53-dependent regulation of heat shock protein 72

BACKGROUND

p53 is a key regulator of the cellular stress response. p53 modulates the transcription of several genes.

OBJECTIVES

To examine the influence of p53 on expression of heat shock protein 72 (HSP72).

METHODS

Two model systems were used. (i) HSP72 expression was studied by Western blot on extracts from p53-proficient or p53-deficient primary mouse keratinocytes, and (ii) archival human anogenital skin from fibroepithelial polyps, human papillomavirus (HPV) 16/18-associated lesions or squamous cell carcinomas (SCCs) was subjected to immunostaining for HSP72.

RESULTS

Basal HSP72 expression was higher in keratinocytes from p53-deficient than from p53-proficient mice. Immunostaining for HSP72 was higher in HPV 16/18 lesions and SCCs, which have reduced p53 protein.

CONCLUSIONS

p53 status may influence the basal level of HSP72.

Significant correlation between expression of heat shock proteins 27, 70 and lymphocyte infiltration in esophageal squamous cell carcinoma

The objective of this study was to clarify the clinicopathologic and prognostic significance of heat shock proteins (HSP) 27 and 70 expression in esophageal squamous cell carcinoma (SCC). Immunohistochemical staining for HSPs 27 and 70 was performed on surgical specimens obtained from 62 patients with esophageal SCC. The expression of both HSPs 27 and 70 correlated inversely with depth of invasion (P<0.05) and pathologic stage (P<0.05), and correlated positively with lymphocyte infiltration (P<0.05). Reduction of HSP 70 expression was significantly correlated with poor prognosis (P<0.05). Patients with HSP 27-negative tumors tended to have a poor prognosis compared with patients with HSP 27-positive tumors. The present findings suggest that HSPs 27 and 70 are significant prognostic factors for esophageal SCC.

HSP70 is selectively over-expressed in the blast cells of the germinal centres and paracortex in reactive lymph nodes

AIMS

We evaluated by immunohistochemistry HSP70 expression in reactive lymph nodes since its morphological expression and location have not been previously described and correlated with lymphocyte kinetics.

METHODS AND RESULTS

Ninety-six cases of non-specific lymphadenitis were immunostained for HSP70, CD20, CD3, Ki67, Bcl-2, CD21. The type and the location of HSP70-positive cells were determined. Their number out of 2000 cells in each germinal centre and in each paracortical area was counted at 60x magnification with the help of a quantitative grid. Seventeen percent of germinal centre cells and 7.6% of the paracortex cells were positive. This difference was highly significant. The positively reacting cells were B-cells and had a blast (centroblast or immunoblast) morphology, with negative mantle and marginal lymphocytes and T-cells. Lymphoplasmacytoid cells and plasma cells reacted only weakly or were negative. Germinal centre antigen-presenting cells and interdigitating dendritic cells reacted from lightly to moderately.

CONCLUSIONS

HSP70 was selectively over-expressed by B-blasts mainly located within germinal centres with a lower number in the paracortex. The difference in the mean number between the two sites was statistically highly significant. No correlation was found with bcl-2 and Ki67 expression. Mantle, marginal and T-lymphocytes were always negative. The biological meaning and role of this over-expression in centroblasts and immunoblasts remain to be elucidated.

Autoantibody to heat shock protein Hsp40 in sera of lung cancer patients

Heat shock protein Hsp40 is a stress protein with chaperone activity and has a cooperative function with Hsp70 in mammalian cells. We examined the possible expression of Hsp40 in lung tumor tissues using immunoblotting and immunohistochemistry, and established an enzyme-linked immunosorbent assay (ELISA) method to detect IgG antibody to Hsp40 in the serum using purified human Hsp40. Sera were obtained from 130 normal subjects and 50 patients with lung cancer. Lung tumor tissues and cells specifically overexpressed Hsp40, and no such expression was detected in normal lung tissues. Compared with normal sera, significantly higher levels of autoantibody to Hsp40 were present in patients with lung cancer. The present study is the first to demonstrate overexpression of Hsp40 in human tumor tissue and the associated presence of autoantibody to Hsp40 in the serum. These results suggest that overexpression of Hsp40 in tumor cells may be recognized as a self-antigen.

Heat shock protein expression in human tumours grown in severe combined immunodeficient mice

The constitutional expression of heat shock proteins (HSP) 27, 70 and 90 in human breast, colon and ovarian cancer cells transplanted into severe combined immunodeficient (SCID) mice was evaluated. In addition their induced expression under chemotherapeutic stress was analyzed. The oestrogen receptor positive breast cancer cell lines (MCF-7, T47D) demonstrated an increased level of HSP 27 and 70 expression compared with oestrogen receptor negative cell lines (BT20, HBL100). After 5-fluorouracil application for 4 days, HSP 27 and 70 expression was increased in HT29 colon tumours. Hence, the human/SCID mouse model is well suited to evaluate the constitutional and induced expression of human HSPs under various experimental conditions.

Colorectal cancer staging and adjuvant chemotherapy

Colorectal cancer is a significant cause of morbidity and mortality in Western populations. The standard of care for staging patients with colorectal cancer to determine prognosis and identify patients who will receive adjuvant therapy continues to be histopathology of regional lymph nodes. However, the significant variability in survival within each staging category likely reflects the heterogeneity of detecting micrometastatic disease employing this technique. Novel molecular markers of micrometastases currently in development will permit more accurate staging of patients with colorectal cancer. These advances in staging will distinguish patients who will maximally benefit from adjuvant therapy from those who have an especially good prognosis in whom chemotherapy can be avoided. In addition, new adjuvant chemotherapeutic agents, novel combinations of those agents and creative dosing schedules currently being investigated will offer considerable advantages with respect to ease of administration, safety and tolerability, quality of life and efficacy. Ultimately, it is anticipated that advances in molecular diagnostics will define unique biochemical characteristics of patients' tumours, permitting individualization of chemotherapeutic regimens employing novel agents that specifically exploit those characteristics.

HLA class I expression on human cancer cells. Implications for effective immunotherapy

Early studies demonstrated the role of cytotoxic T cells as an immune defence mechanism against tumour cells. The demonstration of tumour antigen peptides and their presentation to T cells on major histocompatibility complex class I molecules highlighted the importance of these molecules in effective anti-tumour responses. It is well established that many tumours escape T cell recognition by loss or down regulation of class I molecule expression on the cell surface of tumour cells. Tumours which have lost class I expression are immunoselected and as a result have a propensity for growth and metastatic spread. With the development of cancer vaccine strategies for clinical use, there will be a future role for histocompatibility laboratories in determining class I expression on tumour cells in individual patients. These studies of expression will require not just the demonstration of total class I expression but the demonstration of locus and allele specific class I molecules involved in the relevant tumour peptide presentation. These studies will be pivotal in tailoring individual patient therapies. The identification of appropriate monoclonal antibody reagents for class I expression and techniques used on different kinds of tissue sections will be a component of the forthcoming 13th International Histocompatibility Workshop.

Prognostic significance of heat shock proteins 27 and 70 in patients with squamous cell carcinoma of the esophagus

BACKGROUND

Heat shock proteins (HSPs) first were defined as proteins induced by heat shock and other environmental and pathophysiologic stresses and are implicated in protein-protein interactions such as folding, translocation, and prevention of inappropriate protein aggregation. Many of their functions suggest that they play important roles in cancer.

METHODS

Immunohistochemical study for HSP 27 and HSP 70 was performed on buffered formalin fixed, paraffin embedded sections of 102 esophageal squamous cell carcinoma specimens using monoclonal anti-HSP 27 antibody and anti-HSP 70 antibody.

RESULTS

Normal squamous cells expressed both HSP 27 and HSP 70 with the exception of the basal layer. In cancerous tissue, expression of HSP 27 was evaluated as positive (+) (39 cases; 38%), reduced (+/-) (53 cases; 52%), or negative (-) (10 cases; 10%) and expression of HSP 70 was evaluated as (+) (14 cases; 14%), (+/-) (57 cases; 56%), or (-) (31 cases; 30%). There was a strong correlation between the expression of HSP 27 and HSP 70 (P < 0.0001). When compared with clinicopathologic features, expression of both HSP 27 and HSP 70 correlated negatively with lymph node metastases (P < 0.05), but not with depth of invasion or histologic grade. The reduction of the HSPs was associated significantly with poor postoperative survival (P < 0.0001). In addition, multivariate analysis revealed that HSP 27 (-) was the strongest prognostic factor among the clinicopathologic features.

CONCLUSIONS

This study suggests that the expression of HSP 27 and HSP 70 frequently is reduced in patients with esophageal squamous cell carcinoma and therefore should be considered an independent prognostic factor of this disease.

Characterisation of tumour infiltrating lymphocytes and correlations with immunological surface molecules in colorectal cancer

Using flow cytometry, we studied the phenotype of tumour infiltrating lymphocytes (TILs) in 41 enzymatically dissociated colorectal cancers and compared this to the expression of HLA class I and II and CD80 on tumour cells. We studied the possible enzymatic damage to various surface markers after enzymatic dissociation. The reproducibility of flow cytometric determinations obtained from TILs was good (kappa value: 0.79). The median CD4+/CD8+ ratio was 2.2. Approximately 43-45% (median of cells in each tumour) of both the CD4(+)- and the CD8(+)-TILs expressed HLA class II; 14.2% of the CD4(+)-TILs expressed CD25 and none of the CD8(+)-TILs expressed CD25. CD3-/CD16+/CD56(+)-TILs were very infrequent. Expression of HLA class II did not correlate with any lymphocyte surface markers. Since TILs are "turned off" rather than stimulated when tumour cells express HLA class II but not CD80, the lack of correlations could be due to anergy.