Expression of Immunomodulatory Molecules PD-1, PD-L1, and PD-L2, and their Relationship With Clinicopathologic Characteristics in Endometrial Cancer.

Chemotherapeutic agents are not very effective in treating advanced endometrial cancers (ECs). Recent studies have demonstrated the immune evasion mechanism of tumors and possible remedies. Programmed cell death protein 1 (PD-1), programmed death ligand 1 (PD-L1), and programmed death ligand 2 (PD-L2) are immunomodulator molecules that have been the focus of research in lung cancer, melanoma, and renal cell cancer. However, there are few studies concerning EC. This retrospective study aimed to determine PD-1, PD-L1, and PD-L2 expression immunohistochemically in EC, and to study their correlation with clinicopathologic tumor characteristics. This study comprised 127 patients with EC. Anti PD-1, PD-L1, and PD-L2 antibodies were examined immunohistochemically on sections obtained from tissue microarray paraffin blocks. No staining with PD-1 in tumor cells was seen; however, we found positive staining in tumor cells at 36.2% with PD-L1 and 64.4% with PD-L2, and at 61.6% with PD-1, 36.2% with PD-L1, and 93.2% with PD-L2 in immune cells. When comparing staining and clinicopathologic findings, most of the PD-L1 negative tumors (both in tumor and immune cells) were FIGO Stage I, which was significantly higher than stage II-III-IV tumors (P<0.05). There was a statistically significant association between the FIGO grade and the PD-L1 score in immune cells (P=0.009), and between staining of PD-1, PD-L1, and PD-L2 and age (P=0.004, 0.013, and 0.043, respectively). Interaction between PD-1, PD-L1, and PD-L2 may be a potential target for immunotherapy in elderly and advanced stage EC patients.

Skin punch biopsy sectioning: before or after tissue processing?

BACKGROUND: We intended to study whether there is a meaningful difference in microscopic examination between dividing a biopsy section into two equal parts before tissue processing (first method) or after (second method). METHODS: A total of 400 cases were included in the study. Punch biopsies (PB) were cut into two pieces using the first method in 200 cases and just before paraffin embedding in another 200 cases using the second method. We microscopically evaluated the epidermal mesh view, the presence of a cross-cut hair follicle and bow shape because of epidermal angling, the presence of two pieces on the slide and if there was a difference of >2 mm between the parts, and the number of new sections and new slides. RESULTS: Cross-cut hair follicle (p = 0.018), epidermal mesh view (p = 0.036), difference of >2 mm between the parts (p = 0.008), the number of new sections (p < 0.001) and new slides (p < 0.001) were considerably higher when the first method was used compared with the second method. The presence of two pieces was less (p < 0.001) when using the first method. CONCLUSIONS: We noted a meaningful difference in the quality of microscopic evaluation between the first and second methods. Better sections were obtained with the second method. In addition, the decrease in the number of new slides will reduce workload, archival work and cost.

The Relationship Between DNA Mismatch Repair Status and Clinicopathologic Characteristics in Colon Cancer.

DNA mismatch repair (MMR) proteins are essential for repairing genetic mutations that occur during DNA replication. Deficiency of MMR proteins results in a phenotype called microsatellite instability (MSI), which occurs in Lynch syndrome as well as sporadic colorectal cancers (CRC), and it is associated with several clinicopathological features. We aimed to investigate the association of the loss of MMR proteins with clinicopathologic considerations in our CRC series. In this retrospective study, DNA MMR protein status in CRC is evaluated in a total of 200 colorectal resection specimens by immunohistochemistry (IHC) for MLH1, MSH2, MSH6 and PMS2 protein expression. The BRAF mutation was investigated by the real-time PCR in cases with loss of MLH1 protein expression. The relationship between MMR status and clinicopathological parameters was investigated statistically. Loss of MMR protein expression was detected in 26 of 200 CRC cases. The BRAFV600E mutation was detected in 2 of the cases with MLH1 loss and accepted as sporadic. The remaining 24 cases (12%) were identified as Lynch syndrome candidates. There were statistical differences observed regarding the presence of tumor-infiltrating lymphocytes (P < .001), Crohn's-like reaction (P = .001), expansile growth (P < .001), tumor heterogeneity (P < .001), mucinous differentiation (P < .001), and presence of metastatic lymph nodes (P = .045) between sporadic cases with preserved MMR and Lynch candidates. However, difference in the survival rates between sporadic cases and Lynch candidates was not significant. Immunohistochemical staining for MMR is a practical method for predicting MSI phenotype as well as Lynch candidates. MMR expression status was found to be associated with certain clinicopathological features some of which also have prognostic significance.

Lysyl Oxidase Like-4 (LOXL4) as a tumor marker and prognosticator in advanced stage laryngeal cancer.

INTRODUCTION: Lysyl oxidase-like 4 is an amine oxidase from the lysyl oxidase family that was previously shown to be overexpressed in head and neck cancer and upregulated in response to hypoxia. The possible role of lysyl oxidase-like 4 as a tumor marker in advanced stage larynx cancer was investigated. OBJECTIVE: To investigate the expression of lysyl Oxidase-Like 4 protein in advanced stage laryngeal cancer and elucidate its possible role as a tumor marker, predictor of treatment response and prognosticator. METHODS: Diagnostic specimens of 72 patients treated for stage III-IV laryngeal squamous cell carcinoma were evaluated for lysyl oxidase-like 4 expression by immunohistochemistry. RESULTS: Lysyl oxidase-like 4 expression was correlated with advanced tumor stage (p = 0.041) and better differentiation (p = 0.025) but was independent of tumor diameter (p = 0.456). Response to induction chemotherapy or the need for salvage laryngectomy were not affected by lysyl oxidase-like 4 expression (p = 0.999, p = 0.070 respectively). Increased lysyl oxidase-like 4 expression was associated with better 2 year overall survival in both univariate (p = 0.036) and multivariate analyses (p = 0.014). CONCLUSION: Lysyl oxidase-like 4 expression emerges with advancing stages, is lost with worsening differentiation, and may have tumor suppressive properties in larynx cancer.

Investigation of Heme Oxygenase 2 Enzyme Protein Expression in Keratoconus and Normal Human Corneal Epithelium: An Immunohistochemical Study.

PURPOSE: To compare heme oxygenase 2 (HO-2) enzyme levels detected by immunohistochemical staining methods in the cornea epithelium obtained from keratoconus patients and normal subjects. MATERIALS AND METHODS: The keratoconus group included 69 eyes of 69 patients with keratoconus scheduled for cross-linking surgery. The control group included 52 eyes of 52 patients with refractive error scheduled for photorefractive keratectomy surgery. After a detailed ophthalmologic examination, corneal topographic maps of each patient were generated, and then the patients underwent surgery. The corneal epithelium was collected mechanically during the surgery, fixed with formalin, embedded in paraffin blocks, and sectioned by microtomes. HO-2 antibodies were applied to the samples for immunohistochemical evaluation. The intensity of the staining was identified as negative, weak, moderate or strong. The keratoconus group was classified as early (average keratometry (AvrK) ≤ 47 D), moderate (AvrK 47-55 D) and advanced keratoconus (AvrK ≥ 55 D). Finally, intergroup and intragroup comparison analyses were made statistically. RESULTS: In the keratoconus group, 20 (29%) (14 weak and 6 moderate staining) of the 69 corneal epithelial specimens were identified with HO-2 expression. In the control group, 40 (76.9%) (16 moderate and 24 strong staining) of the 52 corneal epithelial specimens were identified with HO-2 expression. HO-2 expression in the corneal epithelial specimens was significantly less in the keratoconus group than in the control group (p < 0.001). There was no substantial difference among the keratoconus subgroups in terms of staining with the HO-2 antibody (p = 0.797). CONCLUSIONS: The HO-2 enzyme staining using immunohistochemical methods was at lower amounts in the keratoconic corneal epithelial cells as compared with normal corneal epithelial cells. The HO-2 enzyme may play a role in the etiopathogenesis of keratoconus.

Evaluation of p53 and Ki67 Expression Profiles in Basal Cell Carcinomas in a Usual and an Unusual Location.

OBJECTIVE: Owing to their importance in cell proliferation in cutaneous malignancies, we aimed to immunohistochemically compare the expression profiles of p53 and Ki67 in basal cell carcinoma (BCC) cases in both a usual and an unusual locations in this study. MATERIAL AND METHOD: In this study we included 12 in an unusual location of BCC cases and 21 BCC cases in a usual location. Immunohistochemical expression of p53 and Ki67 antibodies were studied in 33 paraffin-embedded tissue specimens of basal cell carcinoma. We compared the p53 and Ki67 staining scores with clinicopathologic features. RESULTS: The tumor size was found to be greater in BCC cases in an unusual location than those in a usual location. The relationship between age and tumor size was also evaluated in both groups and it was found that tumor size increased with age. A comparative study between the two groups showed no difference p53 and Ki67 expression percentages. There was a linear correlation between the Ki67 and p53 marker staining rates (ρ=0.420; p=0.015). In the samples taken from cases in a usual region, there was a linear and moderate relationship between the markers (ρ=0.513; p=0.017). Median tumor diameter results were similar to the marker staining score (p > 0.05). CONCLUSION: This is the first study comparing the expression profiles of p53 and Ki67 of BCC cases in an unusual and a usual location. No significant difference was found concerning Ki67 and p53 expression levels between the two groups.

Prognostic significance of the programmed death ligand 1 expression in clear cell renal cell carcinoma and correlation with the tumor microenvironment and hypoxia-inducible factor expression.

BACKGROUND: Clear cell renal cell carcinoma (ccRCC) is the most common renal malignancy. Hypoxia-inducible factors, HIF-1α and HIF-2α, are expressed in the majority of ccRCC. Targeting immune checkpoints with the blockade of PD-1 and its ligand PD-L1 reorganizes T-cell activity in tumor microenvironment and provides important antitumor responses. PD-L1 upregulation has been found to be hypoxia-inducible factor (HIF) dependent. Our aim is to demonstrate the association between PD-L1 and HIF expression and to reveal the role of PD-L1 in prognosis and its association with tumor microenvironment. METHODS: Surgical specimens from 145 patients diagnosed with ccRCC, who had undergone radical or partial nephrectomy, were retrospectively analyzed. Immunohistochemistry on tissue microarrays (TMA) was performed to demonstrate expressions of PD-L1, HIF-1α, and HIF-2α in tumor cells and PD-1, CD4, and CD8 in lymphocytes to assess lymphocyte density in tumor microenvironment. RESULTS: PD-L1 tumor cell expression was detected in 20/125 (13.8%) cases, which correlated with higher levels of PD-1, CD4, CD8 and HIF-2α expression. Low or high expression of HIF-1α was similar in PD-L1-positive cases. When PD-L1-positive cases were compared with negative ones, there was no significant difference in terms of prognostic factors. However, the number of WHO/ISUP grade 3-4 tumors was significantly higher in PD-L1-positive cases than in negative ones. CONCLUSION: PD-L1 tumor cell expression is strongly associated with increased HIF-2α expression and presence of dense lymphocytic infiltration in ccRCCs. Our findings confirm that PD-L1 positivity is associated with high ISUP nucleolar grade. The association between PD-L1, HIF, and lymphocyte density in tumor microenvironment must be clarified and especially taken into account in combination treatment.

Retrospective analysis of oncogenic human papilloma virus and Epstein-Barr virus prevalence in Turkish nasopharyngeal cancer patients.

Nasopharyngeal carcinoma (NPC) is associated with the Epstein-Barr virus (EBV). Human papilloma virus (HPV) has also been detected in NPC cases. In this retrospective study, we analyze the frequency of EBV and HPV infection in 82 Turkish patients with NPC. A total of 82 were evaluated for EBV and HPV. In situ hybridization (ISH) was performed for EBV. HPV-ISH and P16 immunohistochemistry used to determine the HPV status. Seventy-two of the 82 (87%) NPC patients were EBV-positive. The highest rate of EBV-positivity was found in undifferentiated NPC patients, which accounted for 65 of 68 (95.6%) undifferentiated cases. One of the 82 NPC patients whose tumor was non-keratinizing differentiated, contained HPV. Our data shows that EBV is closely associated with NPC in Turkey. We found lower rates of HPV-positivity in NPC patients than in North American populations. In addition, both EBV and HPV-negativity were more associated with decreased survival than EBV-positive cases.