Cisplatin overcomes radiotherapy resistance in OCT4-expressing head and neck squamous cell carcinoma

OBJECTIVES

Cisplatin is combined with radiotherapy for advanced head and neck squamous cell carcinoma (HNSCC). While providing a beneficial effect on survival, it also causes side effects and thus is an important target when considering treatment de-escalation. Currently, there are no biomarkers to predict its patient-selective therapeutic utility. In this study, we examined the role of the stem cell factor OCT4 as a potential biomarker to help clinicians stratify HNSCC patients between radiotherapy and chemoradiotherapy.

MATERIALS AND METHODS

OCT4 immunohistochemical staining of a population-validated tissue microarray (PV-TMA) (n = 166) representative of a standard HNSCC patients was carried out, and 5-year survival was analyzed. The results were validated using ex vivo drug sensitivity analysis of HNSCC tumor samples, and further cross-validated in independent oropharyngeal (n = 118), nasopharyngeal (n = 170), and vulvar carcinoma (n = 95) clinical datasets. In vitro, genetically modified, patient-derived HNSCC cells were used.

RESULTS

OCT4 expression in HNSCC tumors was associated with radioresistance. However, combination therapy with cisplatin was found to overcome thisradioresistance in OCT4-expressing HNSCC tumors. The results were validated by using several independent patient cohorts. Furthermore, CRISPRa-based OCT4 overexpression in the HNSCC cell line resulted in apoptosis resistance, and cisplatin was found to downregulate OCT4 protein expression in vitro. Ex vivo drug sensitivity analysis of HNSCC tumors confirmed the association between OCT4 expression and cisplatin sensitivity.

CONCLUSION

This study introduces OCT4 immunohistochemistry as a simple and cost-effective diagnostic approach for clinical practice to identify HNSCC patients benefitting from radiosensitization by cisplatin using either full or reduced dosing.

Maternal HPV-antibodies and seroconversion to HPV in children during the first 3 years of life

To assess the dynamics of human papillomavirus (HPV) serology, we analyzed HPV6-,11-,16-,18-, and 45 antibodies in infants during the first 36 months of their life. Serial serum samples of 276/327 mother–child pairs were collected at baseline (mothers) and at months 1, 2, 6, 12, 24 and 36 (offspring), and tested for HPVL1-antibodies using the GST-L1 assay. Concordance between maternal and infant HPV-antibody levels remained high until month-6 (p <  = 0.001), indicating maternal antibody transfer. At 1 month, 40–62% of the infants tested seropositive to any of the 5 HPV-types. Between 1–3 years of age, 53% (58/109) of the children born to HPV-seronegative mothers tested HPV-seropositive. Times to positive seroconversion varied between13.4 and 18.7 months, and times to negative seroconversion (decay) between 8.5 and 9.9 months. Significant independent predictors of infants’ seroconversion to LR-HPV were hand warts and mother’s history of oral warts and seroconversion to LR-HPV. No predictors of seroconversion to HR-HPV were identified. Maternal HPV-IgG-antibodies are transferred to her offspring and remain detectable for 6 months, corroborating the IgG molecule’s half-life. Seroconversion to HPV-genotypes 6, 11, 16 and 18 was confirmed among children born to HPV-seronegative mothers, implicating an immune response to these HPV-genotypes during early infancy.

Oral Human Papillomavirus Infection in Children during the First 6 Years of Life, Finland

Human papillomavirus (HPV) infections are found in children, but transmission modes and outcomes are incompletely understood. We evaluated oral samples from 331 children in Finland who participated in the Finnish Family HPV Study from birth during 9 follow-up visits (mean time 51.9 months). We tested samples for 24 HPV genotypes. Oral HPV prevalence for children varied from 8.7% (at a 36-month visit) to 22.8% (at birth), and 18 HPV genotypes were identified. HPV16 was the most prevalent type to persist, followed by HPV18, HPV33, and HPV6. Persistent, oral, high-risk HPV infection for children was associated with oral HPV carriage of the mother at birth and seroconversion of the mother to high-risk HPV during follow-up (odds ratio 1.60–1.92, 95% CI 1.02–2.74). Children acquire their first oral HPV infection at an early age. The HPV status of the mother has a major impact on the outcome of oral HPV persistence for her offspring.

Ocular Abnormalities in Transgenic Mice Harboring Mutations in the Type Ii Collagen Gene

PURPOSE

To characterize the morphological changes in the eyes of transgenic mice harboring different mutations in type II collagen gene to elucidate the function of this collagen in the eye, and to find out whether these animals could function as models for the human arthro-ophthalmopathies of the Kniest, Stickler and Wagner types.

METHODS

Three genetically engineered mouse lines representing two types of mutations in the triple-helical domain of type II collagen and their nontransgenic littermates used as controls were analyzed on day 18.5 embryonic development. After genotyping by polymerase chain reaction (PCR) and Southern hybridization the embryos were prepared for routine histology. Polarization microscopy was done on hyaluronidase-treated sections.

RESULTS

Histological analysis revealed several genotype-dependent abnormalities in the eyes of the transgenic mice. Most striking changes were observed in the vitreous architecture; in one line of mice the vitreous was tightly packed in the posterior region of the vitreous space with thick fibrils, empty cavities and dense membrane-like material. The other mutation resulted in reduced filament density of the vitreous. In the most severely affected phenotype the internal limiting membrane was detached from the retinal layers and was markedly thickened, and the posterior lens capsule was thickened. The anterior chamber was shallow or absent in all transgenic lines but was well formed in the normal animals. Changes were also observed in the lens, corneal and scleral structures.

CONCLUSIONS

The ocular changes observed in transgenic mice harboring mutations in type II collagen gene show similarities to the human ocular findings in Kniest dysplasia, and in Stickler and Wagner syndromes. We therefore propose that these animals could serve as models for systematic analysis of vitreoretinal degeneration and other abnormalities, as seen in these syndromes.

[Update on current care guidelines. Diagnosis, treatment and follow-up of cytological changes in the cervix, vagina and vulva]

Approximately 150 cervical cancer cases are diagnosed in Finland annually. Both incidence and mortality have decreased by 80% since organised screening began. Recently, screening based on primary HPV-testing with Pap-smear triage has been shown to be more sensitive and more specific among women over 35 years old in randomised studies and thus may be implemented in routine. Abnormal findings in Pap smears indicate management. Confirmed CIN1 lesions are followed up and CIN2 and worse lesions treated. Follow-up after treatment should be reliably arranged, because elevated risk of cancer remains over 20 years after treatment. Quality control is of utmost importance.

Dynamics of human papillomavirus serology in women followed up for 36 months after pregnancy

We determined L1 antibodies for human papillomavirus (HPV) types 6, 11, 16, 18 and 45 by multiplex serology in our prospective HPV family study. We report seroprevalence, seroconversion and antibody decay in 290 women (mean age, 25.5 years) sampled before delivery and at 12, 24 and 36 months of follow-up. Multiplex HPV genotyping of the baseline oral and genital scrapings was performed. At baseline, seroprevalence of HPV 6, 11, 16, 18 and 45 was 53.3, 21.5, 34.9, 21.5 and 9.0 %, respectively. Seropositivity for low-risk HPV (LR-HPV) was associated significantly with age at onset of sexual activity (P=0.001), number of sexual partners until age 20 (P=0.018), lifetime number of sexual partners (P=0.0001), history of genital warts (P=0.0001) and being seropositive for high-risk (HR) HPV (P=0.0001). The same covariates also predicted seropositivity for HR-HPV. During follow-up, 26.7, 13.9, 17.0, 16.8 and 6.6 % of the women seroconverted to L1 antigen of HPV 6, 11, 16, 18 and 45, respectively, between 18.2 and 23.8 months. Independent predictors of seroconversion to LR-HPV were unemployment (P=0.019) and absence of anal sex practice (P=0.031), and to HR-HPV, absence of smoking history and lifetime number of sexual partners. Decay of HPV 6, 11, 16, 18 and 45 antibodies was observed in 2.3, 4.0, 5.3, 4.5 and 1.5 % of the women, respectively, with decay time varying from 27.2 to 35.8 months. These data imply that (i) a substantial proportion of young women are seropositive for both LR- and HR-HPV types, (ii) they frequently undergo seroconversion within 18–24 months, predicted by common covariates, and (iii) antibody decay over 3 years is rare.

Human papillomavirus DNA detected in breast milk

Human papillomavirus (HPV) testing of 223 breast milk samples 3 days postpartum was performed with polymerase chain reaction, hybridization, and sequencing. HPV-16-DNA was detected in 4.0% of the samples. HPV carriage in the breast milk was not correlated with mother's oral or cervical HPV-status or the demographic data. Oral HPV-infection of the spouse at month 6 and 12 postpartum was statistically significantly associated with HPV carriage in the breast milk.

Natural history of oral papillomavirus infections in spouses: a prospective Finnish HPV Family Study

BACKGROUND

The natural history of genital human papillomavirus infection is well known, but nearly nothing is known about the outcome of oral HPV-infection.

OBJECTIVES AND STUDY DESIGN

To study natural history of oral HPV in spouses during the follow-up 331 women (mean 25.5+/-3.4 years) and 131 men (mean 28.8+/-5.0 years) were recruited from maternity unit. Scrapings from healthy oral mucosa of spouses at baseline, 2, 6, 12 and 24 months and genital samples were taken for HPV testing. HPV DNA was detected by nested PCR and confirmed by hybridization using a cocktail of 12 high-risk (HR) oligoprobes.

RESULTS

The detection rate of HR HPVs varied from 15% to 27%. Baseline oral HPV status between the spouses was closely related (odds ratio 4.3; 95% confidence interval 1.6-12.0; P=0.006). Persistent oral infection in one spouse was a significant risk factor (odds ratio 10.0; 95% confidence interval 1.5-68.7; P=0.005) for oral HR HPV persistence in the other partner. Cumulative incidence of new HR HPV infections was identical in both spouses, while men seemed to clear their infection more rapidly. In univariate survival analysis, the partner's oral or genital HPV status, oral sex habits or age did not predict clearance or acquisition of oral HR HPV.

CONCLUSION

Natural history of HPV infection in oral mucosa mimics that of genital HPV infection. Oral sex had no association to oral HPV infection, but a persistent oral HPV infection of the spouse increased the risk of persistent oral HPV infection 10-fold in the other spouse.

Association of syndecan-1 with tumor grade and histology in primary invasive cervical carcinoma

OBJECTIVES

The expression of syndecan-1, a cell surface heparan sulfate proteoglycan, is reduced during malignant transformation of squamous cells. Studies on squamous cell carcinoma of the head and neck have shown that syndecan-1-positive tumors are associated with longer overall and recurrence-free survival. The purpose of this study was to analyze syndecan-1 expression in invasive cervical carcinoma and to examine the association of syndecan-1 expression with prognostic factors and overall survival.

METHODS

The study population consisted of 124 patients treated for primary invasive carcinoma of the uterine cervix at the Turku University Central Hospital during the years 1970-1988. The material consisted of 102 (82.3%) squamous cell carcinomas, 16 (12.9%) adenocarcinomas and 1 (0.8%) adenosquamous carcinoma, 1 (0.8%) small cell carcinoma, 1 (0. 8%) adenoid basal carcinoma, 1 (0.8%) carcinosarcoma, and 2 (1.6%) unclassified cervical carcinomas. Syndecan-1 expression was determined on paraffin-embedded tissue blocks using a human syndecan-1-specific monoclonal antibody B-B4 and immunohistochemistry. The expression of syndecan-1 was classified according to staining intensity as well as the percentage of positively stained tumor cells.

RESULTS

Staining intensity was strong in 44 (36%) samples, while 24 (19%) specimens remained syndecan-1-negative. In 49 (40%) samples, the percentage of syndecan-1-positive cells was >/=90%. Syndecan-1 expression, as determined by >/=50% positively stained tumor cells, was associated with the grade of differentiation (P = 0.03) and squamous histology (P < 0.001), but was not associated with clinical stage (P = 0.16) or disease-free survival (P = 0.86). Age (P = 0.003) and clinical stage (P < 0.001) were significant prognostic factors, but syndecan-1 expression determined neither by percentage of positively stained tumor cells nor by staining intensity was associated with the outcome.

CONCLUSIONS

In cervical carcinoma syndecan-1 is associated with histological differentiation grade and squamous histology, but does not predict clinical outcome.

Tissue-separating capacity of growth cartilages

The tissue-separating capacity of chondral structures has been debated for more than 30 years, and one aspect that has particularly been questioned is whether the secondary cartilage of the mandibular condyle is comparable to primary growth cartilage, e.g. the epiphyseal growth plate. The present report summarizes information gained by using a specific interosseal transplantation method. These findings lead to the conclusion that all the structures examined, i.e. the proximal epiphyseal cartilage of the tibia, the cartilage of the costochondral junction of the ribs, the basicranial synchondroses, the medial cartilage of the clavicle and the mandibular condyle, have the capacity to separate adjoining skeletal structures. The changes induced by the transplanted structures in the recipient area vary, however, suggesting a hierarchial arrangement of cartilages with regard to their tissue-separating capacity. It is suggested that the tissue-separating capacity is a basic phenomenon in the function of growth, not only of primary growth cartilages, but of secondary cartilages as well.

Abnormal craniofacial growth and early mandibular osteoarthritis in mice harbouring a mutant type II collagen transgene

Skull morphology and histology in the heterozygous offspring of a transgenic founder mouse Del1, harbouring 6 copies of deletion mutation in Col2a1 gene, were compared with those in normal siblings. On visual observation and roentgenocephalometric examination the heads of heterozygous Del1 mice were smaller than normal. Histologically the sizes of cartilaginous structures of the cranial base were reduced. Severe defects were seen in the temporomandibular joint as progressive osteoarthritic lesions. These observations elucidate the relationship between the genotype and phenotype and demonstrate that heterozygous Del1 mice are a useful model for studies on a genetic disturbance where 'clinical' manifestations are not evident until adult age.

Abnormalities in secondary cartilages in four lines of transgenic mice harboring two different types of mutations in the cartilage-specific type II collagen gene

A histological analysis was performed on two secondary cartilages, the mandibular condyle and the medial end of clavicle, in transgenic mice harboring two different types of mutations in the cartilage-specific type II collagen gene. Considerable differences were observed in the maturation zone of the chondrocytes and the hypertrophic cells of the growth regions of the two secondary cartilages examined between the transgenic mice and their transgene-negative littermates, which served as controls. Looseness of the perichondrium/periosteum was a distinct feature seen in both mutations. However, phenotypic consequences of the mutations in secondary cartilages were less severe than those in primary cartilages. We propose that the differences between primary and secondary cartilages are due to differences in their origin, mode of growth, architecture and behavior under extrinsic factors.

Abnormal craniofacial morphology and cartilage structure in transgenic mice harboring a Gly --> Cys mutation in the cartilage-specific type II collagen gene

Gross morphology and histology of the craniofacial complex was studied in the offspring of two transgenic founder mice, Gly85-1 and Gly85-3, carrying several copies of a mouse type II collagen transgene that causes a single amino acid substitution (Gly-->Cys) at position 85 of the triple helix. The newborn transgenic mice had a short snout and mandible, a protruding tongue, a cleft of the secondary palate with the tongue situated between the shelves, and a doming cranial vault. Radiological examination revealed that the cranial base of the transgenic mice was shorter and its posterior part downward bent; in addition both the palate and the cribriform plate were less extended in relation to the cranial base than in the controls. Histologically the midline cartilaginous structures were composed of densely packed enlarged chondrocytes in a reduced extracellular matrix containing abnormally thick collagen fibrils. With the exception of the zone of hypertrophic chondrocytes the matrix also showed a loss of glycosaminoglycans. The cellular architecture of the basicranial synchondroses was disorganized, and the nasocerebrally oriented collagen fibrils formed unevenly distributed aggregates. The craniofacial morphology described here for the Gly85 mice shares features typical for other mouse mutations causing short limbed dwarfism. The observations indicate that defective cartilage production causes disproportionate craniofacial growth. Transgenic mice with specific mutations in cartilage-specific genes should therefore be useful for elucidating the complex mechanisms involved in determining the craniofacial growth.

Could mannequins menstruate?

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Chondrodysplasia in transgenic mice harboring a 15-amino acid deletion in the triple helical domain of pro alpha 1(II) collagen chain

We have generated transgenic mice by microinjection of a 39-kb mouse pro alpha 1(II) collagen gene construct containing a deletion of exon 7 and intron 7. This mutation was expected to disturb the assembly and processing of the homotrimeric type II collagen molecule in cartilage. Expression of transgene mRNA at levels equivalent or higher than the endogenous mRNA in the offspring of two founder animals resulted in a severe chondrodysplastic phenotype with short limbs, hypoplastic thorax, abnormal craniofacial development, and other skeletal deformities. The affected pups died at birth due to respiratory distress. Light microscopy of epiphyseal growth plates of transgenic pups demonstrated a marked reduction in cartilaginous extracellular matrix and disruption of the normal organization of the growth plate. The zone of proliferating chondrocytes was greatly reduced whereas the zone of hypertrophic chondrocytes was markedly increased extending deep into the diaphysis suggestive of a defect in endochondral ossification. Electron microscopic examination revealed chondrocytes with extended RER, a very severe reduction in the amount of cartilage collagen fibrils, and abnormalities in their structure. We postulate that the deletion in the alpha 1(II) collagen acts as a dominant negative mutation disrupting the assembly and secretion of type II collagen molecules. The consequences of the mutation include interference with normal endochondral ossification. These mice constitute a valuable model to study the mechanisms underlying human chondrodysplasias and normal bone formation.

Growth potential of the rat clavicle

An experiment was performed to determine whether the clavicle, which is capped with secondary cartilage at both ends, is endowed with a tissue-separating quality or is only adaptive to forces exerted by the surrounding structures. The medial end of the clavicle from 10-day-old male rats was transplanted across the interparietal suture into an opening in the adjoining parietal bones corresponding to the outline of the transplant. The transverse dimensions of the neurocranium when measured at 25 and 35 days of age were greater in the animals with transplants than in the untreated controls. Histologic examination showed that although the cartilaginous component of the transplants was reduced, the zonal arrangements was comparable to that in situ. It was concluded that the medial end of the clavicle has a potential for separating skeletal components and that preservation of the basic structure is dependent on mechanical resistance.