metallothionein and Uterine-Cervical-Neoplasms

Human papillomaviruses (HPV) are small circular, double-stranded DNA viruses infecting epithelial tissues. HPV types can be classified both as high-risk or low-risk. Of the more than 120 different identified types of HPV, the majority are involved in infections of the genital tract, cancer of the cervix, vulva, vagina and penis, and of non-anogenital localizations, such as the head and neck areas. From the point of view of the infection, human papillomaviruses have developed several molecular mechanisms to enable infected cells to suppress apoptosis. This review provides a comprehensive and critical summary of the current literature that focuses on cervical carcinoma and cancer of the head and neck caused by HPV. In particular, we discuss HPV virology, the molecular mechanisms of carcinogenesis, the role of the tumor suppressor protein p53 and the E6/E7 zinc finger proteins. Classification of HPV according to diagnosis is also described.

Topics: Cell Transformation, Neoplastic; Female; Head and Neck Neoplasms; Humans; Metallothionein; Oncogene Proteins, Viral; Papillomaviridae; Papillomavirus E7 Proteins; Papillomavirus Infections; Protein-Tyrosine Kinases; Repressor Proteins; Tumor Suppressor Protein p53; Uterine Cervical Neoplasms; Zinc Fingers

The objective was to discover whether the oxygen-regulated protein, metallothionein, is expressed in the hypoxic cells of squamous cell carcinomas. Twenty patients with squamous cell carcinoma of the uterine cervix or head and neck were infused with a solution of the hypoxia marker, pimonidazole hydrochloride, at a dose of 0.5 g/m2. The following day, biopsies were collected, formalin fixed, paraffin embedded, and sectioned at 4 microm. Sections from each biopsy were immunostained for pimonidazole binding, metallothioneins I and II, involucrin, and proliferating cell nuclear antigen. A total of 84 biopsies were analyzed. Sixty-four of 84 biopsy sections contained hypoxia. Of the hypoxia-containing sections, 43 of 64 or 67% showed no microregional overlap between hypoxia and metallothionein; 7 of 64 showed overlap; and 14 of 64 showed a combination of overlap and no overlap. On a tumor-by-tumor basis, 5 of 7 head and neck and 7 of 13 cervix tumors showed no overlap between metallothionein and hypoxia at the microregional level. Ranges for the percentage of the area of hypoxia in head and neck (<0.9 to 17%) and cervix (<0.1 to 14%) tumors were similar. In the hypoxia-containing sections, immunostaining for involucrin, a molecular marker for differentiation, overlapped with that for hypoxia in 82% of the cases. The majority of hypoxic cells in squamous cell carcinomas do not express metallothionein protein, although metallothionein is induced by hypoxia in human tumor cells in vitro. Hypoxic cells in human tumors tend to be in regions immunostaining for involucrin, and it seems possible that differentiation of hypoxic cells in squamous cell carcinomas might affect metallothionein I and II expression.

Topics: Biomarkers; Carcinoma, Squamous Cell; Cell Hypoxia; Female; Head and Neck Neoplasms; Humans; Immunohistochemistry; Metallothionein; Neoplasm Staging; Nitroimidazoles; Proliferating Cell Nuclear Antigen; Protein Precursors; Uterine Cervical Neoplasms

Cervical cancer represents one of the most important female genital cancers. Cervical squamous cell carcinoma (CESC) accounts for about 90% of all cervical malignancies and the prognosis are unsatisfied. Here we aimed to investigate the clinical relevance of metallothionein-like 5 (MTL5), a novel metallothionein-like protein, in CESC. RT-qPCR and immunohistochemistry staining showed that MTL5 was upregulated in CESC tissues than nontumorous cervix tissues, which is consistent with the data from TCGA database. Kaplan-Meier survival analysis revealed that higher MTL5 can help predict worse prognosis. In addition, Cox hazard regression analysis verified an independent predictive role of MTL5 in CESC. To further investigate the involvement of MTL5 in CESC, we conducted knockdown experiments in two CESC cell lines. As a result, silencing MTL5g significantly inhibited proliferation of CESC cells. Finally, we validated that silencing MTL5 can suppress CESC tumor growth in vivo using the mice subcutaneous xenografts model. Taken together, higher MTL5 indicates worse survival of CESC after surgical resection. Targeting MTL5 represents a potential therapy of CESC by inhibiting tumor growth, which deserves further investigations.

Topics: Animals; Carcinoma, Squamous Cell; Cell Proliferation; Female; Humans; Metallothionein; Mice; Prognosis; Uterine Cervical Neoplasms

Metallothioneins (MTs) are phylogenetically old cysteine-rich proteins, which are implicated in a variety of physiological and pathological processes. Their growth-regulating, anti-apoptotic and anti-inflammatory functions have been attributed not only to intracellular free radical scavenging and to zinc and copper regulation but also to the ability of secreted MT to bind on surface lipoprotein receptor-megalin/LRP2, which enables the endocytosis of MT-I/II and a wide range of other functionally distinct ligands. In the present study, we analysed the expression pattern of both proteins in 55 cases of premalignant transformation of cervical squamous cells, i.e. in low- and high-grade squamous intraepithelial lesion (LSIL and HSIL). The data showed that in LSIL (cervical intraepithelial neoplasia CIN1; N = 25) MTs were present only in basal and parabasal cells and that megalin was only weakly expressed. In HSIL (CIN2; N = 15 and CIN 3/carcinoma in situ; N = 15), however, overexpression and co-localization of MT with megalin were found in the entire hyperplastic epithelium. Moreover, megalin immunoreactivity appeared on the glandular epithelium and vascular endothelium, as well as on lymphatic cells in stroma. Besides, multiple megalin-positive cells expressed phosphorylated Akt1, implying that MT- and/or megalin-dependent prosurvival signal transduction pathways might contribute to the development of severe cervical dysplasia. The data emphasize the diagnostic power of combined MT/megalin analysis in pre-cancer screening.

Topics: Biomarkers, Tumor; Carcinoma, Squamous Cell; Early Detection of Cancer; Female; Gene Expression Profiling; Gene Expression Regulation, Neoplastic; Humans; Immunohistochemistry; Low Density Lipoprotein Receptor-Related Protein-2; Metallothionein; Transcriptome; Tumor Microenvironment; Uterine Cervical Dysplasia; Uterine Cervical Neoplasms

The tumor microenvironment is made up of tissue that is responsible for the growth and progression of the tumor as well as its ability to initiate metastases. The cancer cells on the front of the tumor together with the macrophages and fibroblasts help to constitute the aggressive phenotype of the tumor. The presence of this aggressive phenotype is indicated by the local infiltration of cancer cells and by the development of lymph node metastases. In cases of uterine cancer, the extent of the local and distant spread of the disease is crucial for determining the type of therapeutic strategy to be applied - surgery alone, surgery followed by radio-chemotherapy, or radio-chemotherapy alone. In the interest of trying to improve the patient's quality of life, different studies supporting the therapeutic model of surgery alone have been conducted. While the cancer cells on the tumor front together with the macrophages and the fibroblasts help to constitute the aggressive phenotype of the tumor, metallothionein (MT) has been shown to have both pro-proliferative and anti-apoptotic activities and to participate in microenvironment remodeling. The aim of the current study was to determine the levels of MT immunoreactivity in the uterine cervical cancer cells as well as in the stromal fibroblasts and macrophages of the tumor microenvironment with respect to the depth of the local invasion and the extent of the distant metastases, so that its potential predictive value as a therapeutic strategy for cervical cancer can be ascertained.. We determined the levels of immunoreactivity of MT in a total of 57 carcinoma tissue samples (in the tumor front, in its central part, and in the macrophages and fibroblasts present within the tumor microenvironment). The patients from whom the samples derived were divided into groups with respect to the presence of lymph node metastases (distant spread) and to the depth of invasion (local spread) in relation to the FIGO stage.. Metallothionein immunoreactivity was observed in uterine cervical cancer cells; it was also identified in the fibroblasts and macrophages found within the microenvironments of the tumors of patients suffering from the disease. The MT immunoreactivity level significantly increased within the whole cancer nest in relation to the FIGO stage (intensity of the local spread of the disease). Similarly, the infiltration of MT-positive CAFs and TAMs statistically significantly increased in relation to the FIGO stage.. The level of MT immunoreactivity found in the fibroblasts and macrophages within the tumor microenvironment seems to be indicative of the intensity of the remodeled cervical tumor microenvironment, and this in turn may be related to the local advancement of the disease. Moreover, it appears that the intensity of the metallothionein immunoreactivity in the immunoreactivity profile of the cervical tumor may be linked to both the depth of the local invasion and the extent of the distant advancement of the disease.

Topics: Adult; Aged; Carcinoma, Squamous Cell; Female; Fibroblasts; Humans; Lymphatic Metastasis; Macrophages; Metallothionein; Middle Aged; Tumor Microenvironment; Uterine Cervical Neoplasms

Pimonidazole binding (hypoxia) and involucrin expression (differentiation) overlap extensively in squamous cell carcinomas. This study asks whether involucrin might serve as an endogenous marker for tumor hypoxia. A second question is whether differentiation affects hypoxia-inducible metallothionein (MT) expression in normal human epithelia and squamous cell carcinomas as it does in rodent epithelia.. Thirty-four patients with squamous cell carcinoma of the uterine cervix were infused with pimonidazole hydrochloride solution. The next day, multiple biopsies were formalin-fixed, paraffin-embedded and sectioned at 4 micro m. Qualitative and quantitative analyses for involucrin expression, pimonidazole binding, and human MT-IIa mRNA expression were performed.. No overall correlation between the extent of involucrin expression and pimonidazole binding was observed. The lack of correlation was because of heterogeneous patterns of immunostaining for involucrin generally related to tumor grade. Colocalized immunostaining for involucrin and pimonidazole binding was observed in intermediate grade tumors but not in well-differentiated or poorly differentiated tumors. Human MT-IIa mRNA and MT protein were expressed in basal lamina of normal human epithelia and in the proliferative rims of tumor nests.. Colocalization of immunostaining for involucrin and pimonidazole binding is consistent with oxygen regulation, but the lack of involucrin expression in hypoxic regions of poorly differentiated tumors indicates that its transcriptional status with respect to hypoxia induction is altered by cell differentiation. The localization of MT message and protein in the outer rims of most tumor nests indicates that the transcriptional status of metallothionein is also altered by differentiation.

Topics: Biopsy; Carcinoma, Squamous Cell; Cell Differentiation; Cell Line, Tumor; Female; Humans; Hypoxia; Immunohistochemistry; In Situ Hybridization; Metallothionein; Nitroimidazoles; Oxygen; Prognosis; Protein Precursors; Radiation-Sensitizing Agents; RNA, Messenger; Transcription, Genetic; Uterine Cervical Neoplasms

Metallothioneins (MTs) are ubiquitous low molecular weight proteins with a high affinity for heavy metal ions such as zinc, copper, cadmium, and platinum. Immunohistochemically detectable MT overexpression has been demonstrated in a variety of cancers, especially breast carcinoma. In this study, the immunohistochemical expression of MT in normal cervical squamous epithelia, cervical intraepithelial neoplasms (CINs), and invasive cervical squamous carcinomas was investigated. Immunohistochemical staining for proliferating cells using the MIB1 antibody was also performed. In normal squamous epithelia (n = 31), positive staining with MT was confined to basal and parabasal cells. In cases of koilocytosis (n = 14) and CIN I (n = 10), staining was also largely confined to basal and parabasal cells, with only occasional cases of CIN I exhibiting positivity within higher cell layers. Cases of CIN II (n = 14) showed positive staining largely confined to basal and parabasal cells, with staining of higher cell layers in a few cases. In the majority of cases of CIN III (n = 29), there was diffuse positive staining throughout the full epithelial thickness and, in almost all cases, positive staining was present above the basal and parabasal layers. Positive staining was present in 19 of 21 invasive squamous carcinomas. With MIB 1, positivity was confined to the parabasal layer in normal squamous epithelia. In cases of CIN, positive cells were present in progressively higher cell layers, in accordance with the grade of CIN. There was widespread positive staining in all cases of invasive squamous carcinoma. Overexpression of MT, demonstrated immunohistochemically, is associated with CIN III and invasive cervical squamous carcinoma, lesions which exhibit the highest proliferative activity, as shown by MIB1 immunostaining. MT overexpression in cervical squamous lesions appears to occur at some point along the spectrum of high grade CIN and may be related to cell proliferation.

Topics: Antigens, Nuclear; Autoantigens; Carcinoma, Squamous Cell; Cervix Uteri; Female; Humans; Immunohistochemistry; Ki-67 Antigen; Metallothionein; Nuclear Proteins; Uterine Cervical Dysplasia; Uterine Cervical Neoplasms

We previously found that human cervix carcinoma HeLa cells irradiated with multiple fractions of gamma rays (0.5 Gy daily, five times per week over 6 weeks) become resistant to cis-dichlorodiammineplatinum(II) (cis-DDP), methotrexate (MTX) and vincristine (VCR), but retain the same sensitivity to gamma rays or UV light. In the present report attempts were made to elucidate the mechanisms by which these cells have acquired resistance to cis-DDP and VCR. The sensitivity to different drugs was measured by modified MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) method. Neither buthionine sulfoximine (BSO) nor ethacrinic acid were able to reverse the resistance of preirradiated cells to cis-DDP. Therefore, neither the increased levels of glutathione nor glutathione transferase seem to be involved in resistance to cis-DDP. Preirradiated cells did show resistance to cadmium, indicating the increased levels of metallothioneins in these cells. Resistance of preirradiated cells to vincristine was abolished by the addition of verapamil, indicating that resistance to this drug may depend on the increased expression of plasma membrane P-glycoprotein. It was concluded that mechanisms of resistance of preirradiated cells to cytostatics are multifactorial and involve at least the increased levels of metallothioneins and changes in the plasma membrane. Acquired resistance to cytotoxic drugs induced by preirradiation may be the reason for the reduced response to these drugs after radiation treatment of certain tumors.

Topics: Antimetabolites, Antineoplastic; ATP Binding Cassette Transporter, Subfamily B, Member 1; Buthionine Sulfoximine; Cadmium; Cadmium Chloride; Carrier Proteins; Chlorides; Cisplatin; Dose-Response Relationship, Drug; Drug Resistance; Ethacrynic Acid; Female; Gamma Rays; Glutathione; Glutathione Transferase; HeLa Cells; Humans; Membrane Glycoproteins; Metallothionein; Methionine Sulfoximine; Ultraviolet Rays; Uterine Cervical Neoplasms; Verapamil; Vincristine

The platinum drug chemosensitivity of five human cervical squamous cell carcinoma cell lines (HX/151, HX/155, HX/156, HX/160 and HX/171) derived from previously untreated patients has been determined. Compared to our data obtained previously using human ovarian carcinoma cell lines, all five lines were relatively resistant to cisplatin, carboplatin, iproplatin and tetraplatin. One of the lines (HX/156) was exceptionally sensitive to the novel platinum (IV) ammine/amine dicarboxylates JM216 [bis-acetatoammine dichloro (cyclohexylamine) platinum (IV)] and JM221 [ammine dibutyrato dichloro (cyclohexylamine) platinum (IV)]. The range in IC50 values across the five lines was approximately 2.5-fold for cisplatin, carboplatin and iproplatin, 13-fold for tetraplatin and JM216, and 25-fold for JM221. No significant correlation (P > 0.05) was observed between platinum drug chemosensitivity and either glutathione levels or cadmium chloride sensitivity, an indicator of metallothionein levels. In addition, there was no significant correlation (P > 0.05) between cisplatin cytotoxicity and intracellular cisplatin accumulation or JM216 cytotoxicity and intracellular JM216 accumulation over the dose range 5-100 microM (2 h exposure). The exceptional sensitivity of HX/156 to JM216 appears, at least partially, to be a result of enhanced accumulation of JM216. An 8.6-fold acquired cisplatin resistant stable variant of HX/155 has been generated in vitro. Intracellular cisplatin accumulation was reduced by 2.4 +/- 0.3-fold (mean +/- s.d.) in HX/155cisR across the dose range 1-100 microM (2 h exposure). Glutathione levels in HX/155cisR were elevated by 1.3-fold in terms of protein content and by 1.6-fold in terms of cell number. HX/155cisR was 1.9-fold resistant to cadmium chloride. Total platinum bound to DNA after cisplatin exposure (10, 25, 50 or 100 microM for 2 h) was 3.6 +/- 0.6-fold (mean +/- s.d.) lower in HX/155cisR. Hence the mechanism of acquired cisplatin resistance in HX/155cisR appears to be multifocal, with reduced intracellular drug accumulation and elevated glutathione and metallothionein levels combining to reduce DNA platination levels. While HX/155cisR was cross-resistant to tetraplatin and carboplatin, novel platinum (II) and (IV) ammine/amine complexes, including JM216 and JM221, partially circumvented resistance (resistance factors of 1.5-2). Non cross-resistance was observed to iproplatin and nine non-platinum anticancer agents. Intracellular tetraplatin

Topics: Antineoplastic Agents; Carboplatin; Carcinoma, Squamous Cell; Cell Division; Cell Survival; Cisplatin; Drug Resistance; Drug Screening Assays, Antitumor; Female; Glutathione; Humans; Metallothionein; Molecular Structure; Organoplatinum Compounds; Tumor Cells, Cultured; Uterine Cervical Neoplasms